root/drivers/usb/core/hub.c

DEFINITIONS

1. portspeed
2. usb_hub_to_struct_hub
3. usb_device_supports_lpm
4. usb_set_lpm_mel
5. usb_set_lpm_pel
6. usb_set_lpm_sel
7. usb_set_lpm_parameters
8. get_hub_descriptor
9. clear_hub_feature
10. usb_clear_port_feature
11. set_port_feature
12. to_led_name
13. set_port_led
14. led_work
15. get_hub_status
16. get_port_status
17. hub_ext_port_status
18. hub_port_status
19. hub_resubmit_irq_urb
20. hub_retry_irq_urb
21. kick_hub_wq
22. usb_kick_hub_wq
23. usb_wakeup_notification
24. hub_irq
25. hub_clear_tt_buffer
26. hub_tt_work
27. usb_hub_set_port_power
28. usb_hub_clear_tt_buffer
29. hub_power_on
30. hub_hub_status
31. hub_set_port_link_state
32. hub_port_logical_disconnect
33. usb_remove_device
34. hub_activate
35. hub_init_func2
36. hub_init_func3
37. hub_quiesce
38. hub_pm_barrier_for_all_ports
39. hub_pre_reset
40. hub_post_reset
41. hub_configure
42. hub_release
43. hub_disconnect
44. hub_descriptor_is_sane
45. hub_probe
46. hub_ioctl
47. find_port_owner
48. usb_hub_claim_port
49. usb_hub_release_port
50. usb_hub_release_all_ports
51. usb_device_is_owned
52. recursively_mark_NOTATTACHED
53. usb_set_device_state
54. choose_devnum
55. release_devnum
56. update_devnum
57. hub_free_dev
58. hub_disconnect_children
59. usb_disconnect
60. show_string
61. announce_device
62. announce_device
63. usb_enumerate_device_otg
64. usb_enumerate_device
65. set_usb_port_removable
66. usb_new_device
67. usb_deauthorize_device
68. usb_authorize_device
69. port_speed_is_ssp
70. hub_is_wusb
71. use_new_scheme
72. hub_port_warm_reset_required
73. hub_port_wait_reset
74. hub_port_reset
75. port_is_power_on
76. usb_lock_port
77. usb_unlock_port
78. port_is_suspended
79. check_port_resume_type
80. usb_disable_ltm
81. usb_enable_ltm
82. usb_enable_remote_wakeup
83. usb_disable_remote_wakeup
84. usb_wakeup_enabled_descendants
85. usb_port_suspend
86. finish_port_resume
87. wait_for_connected
88. usb_port_resume
89. usb_remote_wakeup
90. hub_handle_remote_wakeup
91. check_ports_changed
92. hub_suspend
93. report_wakeup_requests
94. hub_resume
95. hub_reset_resume
96. usb_root_hub_lost_power
97. usb_req_set_sel
98. usb_set_device_initiated_lpm
99. usb_set_lpm_timeout
100. usb_enable_link_state
101. usb_disable_link_state
102. usb_disable_lpm
103. usb_unlocked_disable_lpm
104. usb_enable_lpm
105. usb_unlocked_enable_lpm
106. hub_usb3_port_prepare_disable
107. hub_usb3_port_prepare_disable
108. usb_disable_lpm
109. usb_enable_lpm
110. usb_unlocked_disable_lpm
111. usb_unlocked_enable_lpm
112. usb_disable_ltm
113. usb_enable_ltm
114. hub_handle_remote_wakeup
115. hub_port_disable
116. usb_port_disable
117. hub_port_debounce
118. usb_ep0_reinit
119. hub_set_address
120. hub_set_initial_usb2_lpm_policy
121. hub_enable_device
122. hub_port_init
123. check_highspeed
124. hub_power_remaining
125. hub_port_connect
126. hub_port_connect_change
127. port_over_current_notify
128. port_event
129. hub_event
130. usb_hub_init
131. usb_hub_cleanup
132. descriptors_changed
133. usb_reset_and_verify_device
134. usb_reset_device
135. usb_queue_reset_device
136. usb_hub_find_child
137. usb_hub_adjust_deviceremovable
138. usb_get_hub_port_acpi_handle

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * USB hub driver.
   4  *
   5  * (C) Copyright 1999 Linus Torvalds
   6  * (C) Copyright 1999 Johannes Erdfelt
   7  * (C) Copyright 1999 Gregory P. Smith
   8  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   9  *
  10  * Released under the GPLv2 only.
  11  */
  12 
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/module.h>
  16 #include <linux/moduleparam.h>
  17 #include <linux/completion.h>
  18 #include <linux/sched/mm.h>
  19 #include <linux/list.h>
  20 #include <linux/slab.h>
  21 #include <linux/ioctl.h>
  22 #include <linux/usb.h>
  23 #include <linux/usbdevice_fs.h>
  24 #include <linux/usb/hcd.h>
  25 #include <linux/usb/otg.h>
  26 #include <linux/usb/quirks.h>
  27 #include <linux/workqueue.h>
  28 #include <linux/mutex.h>
  29 #include <linux/random.h>
  30 #include <linux/pm_qos.h>
  31 #include <linux/kobject.h>
  32 
  33 #include <linux/uaccess.h>
  34 #include <asm/byteorder.h>
  35 
  36 #include "hub.h"
  37 #include "otg_whitelist.h"
  38 
  39 #define USB_VENDOR_GENESYS_LOGIC                0x05e3
  40 #define USB_VENDOR_SMSC                         0x0424
  41 #define USB_PRODUCT_USB5534B                    0x5534
  42 #define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND        0x01
  43 #define HUB_QUIRK_DISABLE_AUTOSUSPEND           0x02
  44 
  45 #define USB_TP_TRANSMISSION_DELAY       40      /* ns */
  46 #define USB_TP_TRANSMISSION_DELAY_MAX   65535   /* ns */
  47 
  48 /* Protect struct usb_device->state and ->children members
  49  * Note: Both are also protected by ->dev.sem, except that ->state can
  50  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  51 static DEFINE_SPINLOCK(device_state_lock);
  52 
  53 /* workqueue to process hub events */
  54 static struct workqueue_struct *hub_wq;
  55 static void hub_event(struct work_struct *work);
  56 
  57 /* synchronize hub-port add/remove and peering operations */
  58 DEFINE_MUTEX(usb_port_peer_mutex);
  59 
  60 /* cycle leds on hubs that aren't blinking for attention */
  61 static bool blinkenlights;
  62 module_param(blinkenlights, bool, S_IRUGO);
  63 MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  64 
  65 /*
  66  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  67  * 10 seconds to send reply for the initial 64-byte descriptor request.
  68  */
  69 /* define initial 64-byte descriptor request timeout in milliseconds */
  70 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  71 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  72 MODULE_PARM_DESC(initial_descriptor_timeout,
  73                 "initial 64-byte descriptor request timeout in milliseconds "
  74                 "(default 5000 - 5.0 seconds)");
  75 
  76 /*
  77  * As of 2.6.10 we introduce a new USB device initialization scheme which
  78  * closely resembles the way Windows works.  Hopefully it will be compatible
  79  * with a wider range of devices than the old scheme.  However some previously
  80  * working devices may start giving rise to "device not accepting address"
  81  * errors; if that happens the user can try the old scheme by adjusting the
  82  * following module parameters.
  83  *
  84  * For maximum flexibility there are two boolean parameters to control the
  85  * hub driver's behavior.  On the first initialization attempt, if the
  86  * "old_scheme_first" parameter is set then the old scheme will be used,
  87  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  88  * is set, then the driver will make another attempt, using the other scheme.
  89  */
  90 static bool old_scheme_first;
  91 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  92 MODULE_PARM_DESC(old_scheme_first,
  93                  "start with the old device initialization scheme");
  94 
  95 static bool use_both_schemes = 1;
  96 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  97 MODULE_PARM_DESC(use_both_schemes,
  98                 "try the other device initialization scheme if the "
  99                 "first one fails");
 100 
 101 /* Mutual exclusion for EHCI CF initialization.  This interferes with
 102  * port reset on some companion controllers.
 103  */
 104 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 105 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 106 
 107 #define HUB_DEBOUNCE_TIMEOUT    2000
 108 #define HUB_DEBOUNCE_STEP         25
 109 #define HUB_DEBOUNCE_STABLE      100
 110 
 111 static void hub_release(struct kref *kref);
 112 static int usb_reset_and_verify_device(struct usb_device *udev);
 113 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 114 static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
 115                 u16 portstatus);
 116 
 117 static inline char *portspeed(struct usb_hub *hub, int portstatus)
 118 {
 119         if (hub_is_superspeedplus(hub->hdev))
 120                 return "10.0 Gb/s";
 121         if (hub_is_superspeed(hub->hdev))
 122                 return "5.0 Gb/s";
 123         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 124                 return "480 Mb/s";
 125         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 126                 return "1.5 Mb/s";
 127         else
 128                 return "12 Mb/s";
 129 }
 130 
 131 /* Note that hdev or one of its children must be locked! */
 132 struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 133 {
 134         if (!hdev || !hdev->actconfig || !hdev->maxchild)
 135                 return NULL;
 136         return usb_get_intfdata(hdev->actconfig->interface[0]);
 137 }
 138 
 139 int usb_device_supports_lpm(struct usb_device *udev)
 140 {
 141         /* Some devices have trouble with LPM */
 142         if (udev->quirks & USB_QUIRK_NO_LPM)
 143                 return 0;
 144 
 145         /* USB 2.1 (and greater) devices indicate LPM support through
 146          * their USB 2.0 Extended Capabilities BOS descriptor.
 147          */
 148         if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 149                 if (udev->bos->ext_cap &&
 150                         (USB_LPM_SUPPORT &
 151                          le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 152                         return 1;
 153                 return 0;
 154         }
 155 
 156         /*
 157          * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 158          * However, there are some that don't, and they set the U1/U2 exit
 159          * latencies to zero.
 160          */
 161         if (!udev->bos->ss_cap) {
 162                 dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 163                 return 0;
 164         }
 165 
 166         if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 167                         udev->bos->ss_cap->bU2DevExitLat == 0) {
 168                 if (udev->parent)
 169                         dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 170                 else
 171                         dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 172                 return 0;
 173         }
 174 
 175         if (!udev->parent || udev->parent->lpm_capable)
 176                 return 1;
 177         return 0;
 178 }
 179 
 180 /*
 181  * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
 182  * either U1 or U2.
 183  */
 184 static void usb_set_lpm_mel(struct usb_device *udev,
 185                 struct usb3_lpm_parameters *udev_lpm_params,
 186                 unsigned int udev_exit_latency,
 187                 struct usb_hub *hub,
 188                 struct usb3_lpm_parameters *hub_lpm_params,
 189                 unsigned int hub_exit_latency)
 190 {
 191         unsigned int total_mel;
 192         unsigned int device_mel;
 193         unsigned int hub_mel;
 194 
 195         /*
 196          * Calculate the time it takes to transition all links from the roothub
 197          * to the parent hub into U0.  The parent hub must then decode the
 198          * packet (hub header decode latency) to figure out which port it was
 199          * bound for.
 200          *
 201          * The Hub Header decode latency is expressed in 0.1us intervals (0x1
 202          * means 0.1us).  Multiply that by 100 to get nanoseconds.
 203          */
 204         total_mel = hub_lpm_params->mel +
 205                 (hub->descriptor->u.ss.bHubHdrDecLat * 100);
 206 
 207         /*
 208          * How long will it take to transition the downstream hub's port into
 209          * U0?  The greater of either the hub exit latency or the device exit
 210          * latency.
 211          *
 212          * The BOS U1/U2 exit latencies are expressed in 1us intervals.
 213          * Multiply that by 1000 to get nanoseconds.
 214          */
 215         device_mel = udev_exit_latency * 1000;
 216         hub_mel = hub_exit_latency * 1000;
 217         if (device_mel > hub_mel)
 218                 total_mel += device_mel;
 219         else
 220                 total_mel += hub_mel;
 221 
 222         udev_lpm_params->mel = total_mel;
 223 }
 224 
 225 /*
 226  * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 227  * a transition from either U1 or U2.
 228  */
 229 static void usb_set_lpm_pel(struct usb_device *udev,
 230                 struct usb3_lpm_parameters *udev_lpm_params,
 231                 unsigned int udev_exit_latency,
 232                 struct usb_hub *hub,
 233                 struct usb3_lpm_parameters *hub_lpm_params,
 234                 unsigned int hub_exit_latency,
 235                 unsigned int port_to_port_exit_latency)
 236 {
 237         unsigned int first_link_pel;
 238         unsigned int hub_pel;
 239 
 240         /*
 241          * First, the device sends an LFPS to transition the link between the
 242          * device and the parent hub into U0.  The exit latency is the bigger of
 243          * the device exit latency or the hub exit latency.
 244          */
 245         if (udev_exit_latency > hub_exit_latency)
 246                 first_link_pel = udev_exit_latency * 1000;
 247         else
 248                 first_link_pel = hub_exit_latency * 1000;
 249 
 250         /*
 251          * When the hub starts to receive the LFPS, there is a slight delay for
 252          * it to figure out that one of the ports is sending an LFPS.  Then it
 253          * will forward the LFPS to its upstream link.  The exit latency is the
 254          * delay, plus the PEL that we calculated for this hub.
 255          */
 256         hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 257 
 258         /*
 259          * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 260          * is the greater of the two exit latencies.
 261          */
 262         if (first_link_pel > hub_pel)
 263                 udev_lpm_params->pel = first_link_pel;
 264         else
 265                 udev_lpm_params->pel = hub_pel;
 266 }
 267 
 268 /*
 269  * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 270  * when a device initiates a transition to U0, until when it will receive the
 271  * first packet from the host controller.
 272  *
 273  * Section C.1.5.1 describes the four components to this:
 274  *  - t1: device PEL
 275  *  - t2: time for the ERDY to make it from the device to the host.
 276  *  - t3: a host-specific delay to process the ERDY.
 277  *  - t4: time for the packet to make it from the host to the device.
 278  *
 279  * t3 is specific to both the xHCI host and the platform the host is integrated
 280  * into.  The Intel HW folks have said it's negligible, FIXME if a different
 281  * vendor says otherwise.
 282  */
 283 static void usb_set_lpm_sel(struct usb_device *udev,
 284                 struct usb3_lpm_parameters *udev_lpm_params)
 285 {
 286         struct usb_device *parent;
 287         unsigned int num_hubs;
 288         unsigned int total_sel;
 289 
 290         /* t1 = device PEL */
 291         total_sel = udev_lpm_params->pel;
 292         /* How many external hubs are in between the device & the root port. */
 293         for (parent = udev->parent, num_hubs = 0; parent->parent;
 294                         parent = parent->parent)
 295                 num_hubs++;
 296         /* t2 = 2.1us + 250ns * (num_hubs - 1) */
 297         if (num_hubs > 0)
 298                 total_sel += 2100 + 250 * (num_hubs - 1);
 299 
 300         /* t4 = 250ns * num_hubs */
 301         total_sel += 250 * num_hubs;
 302 
 303         udev_lpm_params->sel = total_sel;
 304 }
 305 
 306 static void usb_set_lpm_parameters(struct usb_device *udev)
 307 {
 308         struct usb_hub *hub;
 309         unsigned int port_to_port_delay;
 310         unsigned int udev_u1_del;
 311         unsigned int udev_u2_del;
 312         unsigned int hub_u1_del;
 313         unsigned int hub_u2_del;
 314 
 315         if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 316                 return;
 317 
 318         hub = usb_hub_to_struct_hub(udev->parent);
 319         /* It doesn't take time to transition the roothub into U0, since it
 320          * doesn't have an upstream link.
 321          */
 322         if (!hub)
 323                 return;
 324 
 325         udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 326         udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 327         hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 328         hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 329 
 330         usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 331                         hub, &udev->parent->u1_params, hub_u1_del);
 332 
 333         usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 334                         hub, &udev->parent->u2_params, hub_u2_del);
 335 
 336         /*
 337          * Appendix C, section C.2.2.2, says that there is a slight delay from
 338          * when the parent hub notices the downstream port is trying to
 339          * transition to U0 to when the hub initiates a U0 transition on its
 340          * upstream port.  The section says the delays are tPort2PortU1EL and
 341          * tPort2PortU2EL, but it doesn't define what they are.
 342          *
 343          * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 344          * about the same delays.  Use the maximum delay calculations from those
 345          * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 346          * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 347          * assume the device exit latencies they are talking about are the hub
 348          * exit latencies.
 349          *
 350          * What do we do if the U2 exit latency is less than the U1 exit
 351          * latency?  It's possible, although not likely...
 352          */
 353         port_to_port_delay = 1;
 354 
 355         usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 356                         hub, &udev->parent->u1_params, hub_u1_del,
 357                         port_to_port_delay);
 358 
 359         if (hub_u2_del > hub_u1_del)
 360                 port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 361         else
 362                 port_to_port_delay = 1 + hub_u1_del;
 363 
 364         usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 365                         hub, &udev->parent->u2_params, hub_u2_del,
 366                         port_to_port_delay);
 367 
 368         /* Now that we've got PEL, calculate SEL. */
 369         usb_set_lpm_sel(udev, &udev->u1_params);
 370         usb_set_lpm_sel(udev, &udev->u2_params);
 371 }
 372 
 373 /* USB 2.0 spec Section 11.24.4.5 */
 374 static int get_hub_descriptor(struct usb_device *hdev,
 375                 struct usb_hub_descriptor *desc)
 376 {
 377         int i, ret, size;
 378         unsigned dtype;
 379 
 380         if (hub_is_superspeed(hdev)) {
 381                 dtype = USB_DT_SS_HUB;
 382                 size = USB_DT_SS_HUB_SIZE;
 383         } else {
 384                 dtype = USB_DT_HUB;
 385                 size = sizeof(struct usb_hub_descriptor);
 386         }
 387 
 388         for (i = 0; i < 3; i++) {
 389                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 390                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 391                         dtype << 8, 0, desc, size,
 392                         USB_CTRL_GET_TIMEOUT);
 393                 if (hub_is_superspeed(hdev)) {
 394                         if (ret == size)
 395                                 return ret;
 396                 } else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
 397                         /* Make sure we have the DeviceRemovable field. */
 398                         size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
 399                         if (ret < size)
 400                                 return -EMSGSIZE;
 401                         return ret;
 402                 }
 403         }
 404         return -EINVAL;
 405 }
 406 
 407 /*
 408  * USB 2.0 spec Section 11.24.2.1
 409  */
 410 static int clear_hub_feature(struct usb_device *hdev, int feature)
 411 {
 412         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 413                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 414 }
 415 
 416 /*
 417  * USB 2.0 spec Section 11.24.2.2
 418  */
 419 int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 420 {
 421         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 422                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 423                 NULL, 0, 1000);
 424 }
 425 
 426 /*
 427  * USB 2.0 spec Section 11.24.2.13
 428  */
 429 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 430 {
 431         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 432                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 433                 NULL, 0, 1000);
 434 }
 435 
 436 static char *to_led_name(int selector)
 437 {
 438         switch (selector) {
 439         case HUB_LED_AMBER:
 440                 return "amber";
 441         case HUB_LED_GREEN:
 442                 return "green";
 443         case HUB_LED_OFF:
 444                 return "off";
 445         case HUB_LED_AUTO:
 446                 return "auto";
 447         default:
 448                 return "??";
 449         }
 450 }
 451 
 452 /*
 453  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 454  * for info about using port indicators
 455  */
 456 static void set_port_led(struct usb_hub *hub, int port1, int selector)
 457 {
 458         struct usb_port *port_dev = hub->ports[port1 - 1];
 459         int status;
 460 
 461         status = set_port_feature(hub->hdev, (selector << 8) | port1,
 462                         USB_PORT_FEAT_INDICATOR);
 463         dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 464                 to_led_name(selector), status);
 465 }
 466 
 467 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 468 
 469 static void led_work(struct work_struct *work)
 470 {
 471         struct usb_hub          *hub =
 472                 container_of(work, struct usb_hub, leds.work);
 473         struct usb_device       *hdev = hub->hdev;
 474         unsigned                i;
 475         unsigned                changed = 0;
 476         int                     cursor = -1;
 477 
 478         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 479                 return;
 480 
 481         for (i = 0; i < hdev->maxchild; i++) {
 482                 unsigned        selector, mode;
 483 
 484                 /* 30%-50% duty cycle */
 485 
 486                 switch (hub->indicator[i]) {
 487                 /* cycle marker */
 488                 case INDICATOR_CYCLE:
 489                         cursor = i;
 490                         selector = HUB_LED_AUTO;
 491                         mode = INDICATOR_AUTO;
 492                         break;
 493                 /* blinking green = sw attention */
 494                 case INDICATOR_GREEN_BLINK:
 495                         selector = HUB_LED_GREEN;
 496                         mode = INDICATOR_GREEN_BLINK_OFF;
 497                         break;
 498                 case INDICATOR_GREEN_BLINK_OFF:
 499                         selector = HUB_LED_OFF;
 500                         mode = INDICATOR_GREEN_BLINK;
 501                         break;
 502                 /* blinking amber = hw attention */
 503                 case INDICATOR_AMBER_BLINK:
 504                         selector = HUB_LED_AMBER;
 505                         mode = INDICATOR_AMBER_BLINK_OFF;
 506                         break;
 507                 case INDICATOR_AMBER_BLINK_OFF:
 508                         selector = HUB_LED_OFF;
 509                         mode = INDICATOR_AMBER_BLINK;
 510                         break;
 511                 /* blink green/amber = reserved */
 512                 case INDICATOR_ALT_BLINK:
 513                         selector = HUB_LED_GREEN;
 514                         mode = INDICATOR_ALT_BLINK_OFF;
 515                         break;
 516                 case INDICATOR_ALT_BLINK_OFF:
 517                         selector = HUB_LED_AMBER;
 518                         mode = INDICATOR_ALT_BLINK;
 519                         break;
 520                 default:
 521                         continue;
 522                 }
 523                 if (selector != HUB_LED_AUTO)
 524                         changed = 1;
 525                 set_port_led(hub, i + 1, selector);
 526                 hub->indicator[i] = mode;
 527         }
 528         if (!changed && blinkenlights) {
 529                 cursor++;
 530                 cursor %= hdev->maxchild;
 531                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 532                 hub->indicator[cursor] = INDICATOR_CYCLE;
 533                 changed++;
 534         }
 535         if (changed)
 536                 queue_delayed_work(system_power_efficient_wq,
 537                                 &hub->leds, LED_CYCLE_PERIOD);
 538 }
 539 
 540 /* use a short timeout for hub/port status fetches */
 541 #define USB_STS_TIMEOUT         1000
 542 #define USB_STS_RETRIES         5
 543 
 544 /*
 545  * USB 2.0 spec Section 11.24.2.6
 546  */
 547 static int get_hub_status(struct usb_device *hdev,
 548                 struct usb_hub_status *data)
 549 {
 550         int i, status = -ETIMEDOUT;
 551 
 552         for (i = 0; i < USB_STS_RETRIES &&
 553                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
 554                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 555                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 556                         data, sizeof(*data), USB_STS_TIMEOUT);
 557         }
 558         return status;
 559 }
 560 
 561 /*
 562  * USB 2.0 spec Section 11.24.2.7
 563  * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 564  */
 565 static int get_port_status(struct usb_device *hdev, int port1,
 566                            void *data, u16 value, u16 length)
 567 {
 568         int i, status = -ETIMEDOUT;
 569 
 570         for (i = 0; i < USB_STS_RETRIES &&
 571                         (status == -ETIMEDOUT || status == -EPIPE); i++) {
 572                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 573                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
 574                         port1, data, length, USB_STS_TIMEOUT);
 575         }
 576         return status;
 577 }
 578 
 579 static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 580                                u16 *status, u16 *change, u32 *ext_status)
 581 {
 582         int ret;
 583         int len = 4;
 584 
 585         if (type != HUB_PORT_STATUS)
 586                 len = 8;
 587 
 588         mutex_lock(&hub->status_mutex);
 589         ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 590         if (ret < len) {
 591                 if (ret != -ENODEV)
 592                         dev_err(hub->intfdev,
 593                                 "%s failed (err = %d)\n", __func__, ret);
 594                 if (ret >= 0)
 595                         ret = -EIO;
 596         } else {
 597                 *status = le16_to_cpu(hub->status->port.wPortStatus);
 598                 *change = le16_to_cpu(hub->status->port.wPortChange);
 599                 if (type != HUB_PORT_STATUS && ext_status)
 600                         *ext_status = le32_to_cpu(
 601                                 hub->status->port.dwExtPortStatus);
 602                 ret = 0;
 603         }
 604         mutex_unlock(&hub->status_mutex);
 605         return ret;
 606 }
 607 
 608 static int hub_port_status(struct usb_hub *hub, int port1,
 609                 u16 *status, u16 *change)
 610 {
 611         return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 612                                    status, change, NULL);
 613 }
 614 
 615 static void hub_resubmit_irq_urb(struct usb_hub *hub)
 616 {
 617         unsigned long flags;
 618         int status;
 619 
 620         spin_lock_irqsave(&hub->irq_urb_lock, flags);
 621 
 622         if (hub->quiescing) {
 623                 spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 624                 return;
 625         }
 626 
 627         status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 628         if (status && status != -ENODEV && status != -EPERM &&
 629             status != -ESHUTDOWN) {
 630                 dev_err(hub->intfdev, "resubmit --> %d\n", status);
 631                 mod_timer(&hub->irq_urb_retry, jiffies + HZ);
 632         }
 633 
 634         spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 635 }
 636 
 637 static void hub_retry_irq_urb(struct timer_list *t)
 638 {
 639         struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 640 
 641         hub_resubmit_irq_urb(hub);
 642 }
 643 
 644 
 645 static void kick_hub_wq(struct usb_hub *hub)
 646 {
 647         struct usb_interface *intf;
 648 
 649         if (hub->disconnected || work_pending(&hub->events))
 650                 return;
 651 
 652         /*
 653          * Suppress autosuspend until the event is proceed.
 654          *
 655          * Be careful and make sure that the symmetric operation is
 656          * always called. We are here only when there is no pending
 657          * work for this hub. Therefore put the interface either when
 658          * the new work is called or when it is canceled.
 659          */
 660         intf = to_usb_interface(hub->intfdev);
 661         usb_autopm_get_interface_no_resume(intf);
 662         kref_get(&hub->kref);
 663 
 664         if (queue_work(hub_wq, &hub->events))
 665                 return;
 666 
 667         /* the work has already been scheduled */
 668         usb_autopm_put_interface_async(intf);
 669         kref_put(&hub->kref, hub_release);
 670 }
 671 
 672 void usb_kick_hub_wq(struct usb_device *hdev)
 673 {
 674         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 675 
 676         if (hub)
 677                 kick_hub_wq(hub);
 678 }
 679 
 680 /*
 681  * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 682  * Notification, which indicates it had initiated remote wakeup.
 683  *
 684  * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 685  * device initiates resume, so the USB core will not receive notice of the
 686  * resume through the normal hub interrupt URB.
 687  */
 688 void usb_wakeup_notification(struct usb_device *hdev,
 689                 unsigned int portnum)
 690 {
 691         struct usb_hub *hub;
 692         struct usb_port *port_dev;
 693 
 694         if (!hdev)
 695                 return;
 696 
 697         hub = usb_hub_to_struct_hub(hdev);
 698         if (hub) {
 699                 port_dev = hub->ports[portnum - 1];
 700                 if (port_dev && port_dev->child)
 701                         pm_wakeup_event(&port_dev->child->dev, 0);
 702 
 703                 set_bit(portnum, hub->wakeup_bits);
 704                 kick_hub_wq(hub);
 705         }
 706 }
 707 EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 708 
 709 /* completion function, fires on port status changes and various faults */
 710 static void hub_irq(struct urb *urb)
 711 {
 712         struct usb_hub *hub = urb->context;
 713         int status = urb->status;
 714         unsigned i;
 715         unsigned long bits;
 716 
 717         switch (status) {
 718         case -ENOENT:           /* synchronous unlink */
 719         case -ECONNRESET:       /* async unlink */
 720         case -ESHUTDOWN:        /* hardware going away */
 721                 return;
 722 
 723         default:                /* presumably an error */
 724                 /* Cause a hub reset after 10 consecutive errors */
 725                 dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 726                 if ((++hub->nerrors < 10) || hub->error)
 727                         goto resubmit;
 728                 hub->error = status;
 729                 /* FALL THROUGH */
 730 
 731         /* let hub_wq handle things */
 732         case 0:                 /* we got data:  port status changed */
 733                 bits = 0;
 734                 for (i = 0; i < urb->actual_length; ++i)
 735                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 736                                         << (i*8);
 737                 hub->event_bits[0] = bits;
 738                 break;
 739         }
 740 
 741         hub->nerrors = 0;
 742 
 743         /* Something happened, let hub_wq figure it out */
 744         kick_hub_wq(hub);
 745 
 746 resubmit:
 747         hub_resubmit_irq_urb(hub);
 748 }
 749 
 750 /* USB 2.0 spec Section 11.24.2.3 */
 751 static inline int
 752 hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 753 {
 754         /* Need to clear both directions for control ep */
 755         if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 756                         USB_ENDPOINT_XFER_CONTROL) {
 757                 int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 758                                 HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 759                                 devinfo ^ 0x8000, tt, NULL, 0, 1000);
 760                 if (status)
 761                         return status;
 762         }
 763         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 764                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 765                                tt, NULL, 0, 1000);
 766 }
 767 
 768 /*
 769  * enumeration blocks hub_wq for a long time. we use keventd instead, since
 770  * long blocking there is the exception, not the rule.  accordingly, HCDs
 771  * talking to TTs must queue control transfers (not just bulk and iso), so
 772  * both can talk to the same hub concurrently.
 773  */
 774 static void hub_tt_work(struct work_struct *work)
 775 {
 776         struct usb_hub          *hub =
 777                 container_of(work, struct usb_hub, tt.clear_work);
 778         unsigned long           flags;
 779 
 780         spin_lock_irqsave(&hub->tt.lock, flags);
 781         while (!list_empty(&hub->tt.clear_list)) {
 782                 struct list_head        *next;
 783                 struct usb_tt_clear     *clear;
 784                 struct usb_device       *hdev = hub->hdev;
 785                 const struct hc_driver  *drv;
 786                 int                     status;
 787 
 788                 next = hub->tt.clear_list.next;
 789                 clear = list_entry(next, struct usb_tt_clear, clear_list);
 790                 list_del(&clear->clear_list);
 791 
 792                 /* drop lock so HCD can concurrently report other TT errors */
 793                 spin_unlock_irqrestore(&hub->tt.lock, flags);
 794                 status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 795                 if (status && status != -ENODEV)
 796                         dev_err(&hdev->dev,
 797                                 "clear tt %d (%04x) error %d\n",
 798                                 clear->tt, clear->devinfo, status);
 799 
 800                 /* Tell the HCD, even if the operation failed */
 801                 drv = clear->hcd->driver;
 802                 if (drv->clear_tt_buffer_complete)
 803                         (drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 804 
 805                 kfree(clear);
 806                 spin_lock_irqsave(&hub->tt.lock, flags);
 807         }
 808         spin_unlock_irqrestore(&hub->tt.lock, flags);
 809 }
 810 
 811 /**
 812  * usb_hub_set_port_power - control hub port's power state
 813  * @hdev: USB device belonging to the usb hub
 814  * @hub: target hub
 815  * @port1: port index
 816  * @set: expected status
 817  *
 818  * call this function to control port's power via setting or
 819  * clearing the port's PORT_POWER feature.
 820  *
 821  * Return: 0 if successful. A negative error code otherwise.
 822  */
 823 int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 824                            int port1, bool set)
 825 {
 826         int ret;
 827 
 828         if (set)
 829                 ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 830         else
 831                 ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 832 
 833         if (ret)
 834                 return ret;
 835 
 836         if (set)
 837                 set_bit(port1, hub->power_bits);
 838         else
 839                 clear_bit(port1, hub->power_bits);
 840         return 0;
 841 }
 842 
 843 /**
 844  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 845  * @urb: an URB associated with the failed or incomplete split transaction
 846  *
 847  * High speed HCDs use this to tell the hub driver that some split control or
 848  * bulk transaction failed in a way that requires clearing internal state of
 849  * a transaction translator.  This is normally detected (and reported) from
 850  * interrupt context.
 851  *
 852  * It may not be possible for that hub to handle additional full (or low)
 853  * speed transactions until that state is fully cleared out.
 854  *
 855  * Return: 0 if successful. A negative error code otherwise.
 856  */
 857 int usb_hub_clear_tt_buffer(struct urb *urb)
 858 {
 859         struct usb_device       *udev = urb->dev;
 860         int                     pipe = urb->pipe;
 861         struct usb_tt           *tt = udev->tt;
 862         unsigned long           flags;
 863         struct usb_tt_clear     *clear;
 864 
 865         /* we've got to cope with an arbitrary number of pending TT clears,
 866          * since each TT has "at least two" buffers that can need it (and
 867          * there can be many TTs per hub).  even if they're uncommon.
 868          */
 869         clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 870         if (clear == NULL) {
 871                 dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 872                 /* FIXME recover somehow ... RESET_TT? */
 873                 return -ENOMEM;
 874         }
 875 
 876         /* info that CLEAR_TT_BUFFER needs */
 877         clear->tt = tt->multi ? udev->ttport : 1;
 878         clear->devinfo = usb_pipeendpoint (pipe);
 879         clear->devinfo |= ((u16)udev->devaddr) << 4;
 880         clear->devinfo |= usb_pipecontrol(pipe)
 881                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 882                         : (USB_ENDPOINT_XFER_BULK << 11);
 883         if (usb_pipein(pipe))
 884                 clear->devinfo |= 1 << 15;
 885 
 886         /* info for completion callback */
 887         clear->hcd = bus_to_hcd(udev->bus);
 888         clear->ep = urb->ep;
 889 
 890         /* tell keventd to clear state for this TT */
 891         spin_lock_irqsave(&tt->lock, flags);
 892         list_add_tail(&clear->clear_list, &tt->clear_list);
 893         schedule_work(&tt->clear_work);
 894         spin_unlock_irqrestore(&tt->lock, flags);
 895         return 0;
 896 }
 897 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 898 
 899 static void hub_power_on(struct usb_hub *hub, bool do_delay)
 900 {
 901         int port1;
 902 
 903         /* Enable power on each port.  Some hubs have reserved values
 904          * of LPSM (> 2) in their descriptors, even though they are
 905          * USB 2.0 hubs.  Some hubs do not implement port-power switching
 906          * but only emulate it.  In all cases, the ports won't work
 907          * unless we send these messages to the hub.
 908          */
 909         if (hub_is_port_power_switchable(hub))
 910                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 911         else
 912                 dev_dbg(hub->intfdev, "trying to enable port power on "
 913                                 "non-switchable hub\n");
 914         for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 915                 if (test_bit(port1, hub->power_bits))
 916                         set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 917                 else
 918                         usb_clear_port_feature(hub->hdev, port1,
 919                                                 USB_PORT_FEAT_POWER);
 920         if (do_delay)
 921                 msleep(hub_power_on_good_delay(hub));
 922 }
 923 
 924 static int hub_hub_status(struct usb_hub *hub,
 925                 u16 *status, u16 *change)
 926 {
 927         int ret;
 928 
 929         mutex_lock(&hub->status_mutex);
 930         ret = get_hub_status(hub->hdev, &hub->status->hub);
 931         if (ret < 0) {
 932                 if (ret != -ENODEV)
 933                         dev_err(hub->intfdev,
 934                                 "%s failed (err = %d)\n", __func__, ret);
 935         } else {
 936                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 937                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 938                 ret = 0;
 939         }
 940         mutex_unlock(&hub->status_mutex);
 941         return ret;
 942 }
 943 
 944 static int hub_set_port_link_state(struct usb_hub *hub, int port1,
 945                         unsigned int link_status)
 946 {
 947         return set_port_feature(hub->hdev,
 948                         port1 | (link_status << 3),
 949                         USB_PORT_FEAT_LINK_STATE);
 950 }
 951 
 952 /*
 953  * Disable a port and mark a logical connect-change event, so that some
 954  * time later hub_wq will disconnect() any existing usb_device on the port
 955  * and will re-enumerate if there actually is a device attached.
 956  */
 957 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 958 {
 959         dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
 960         hub_port_disable(hub, port1, 1);
 961 
 962         /* FIXME let caller ask to power down the port:
 963          *  - some devices won't enumerate without a VBUS power cycle
 964          *  - SRP saves power that way
 965          *  - ... new call, TBD ...
 966          * That's easy if this hub can switch power per-port, and
 967          * hub_wq reactivates the port later (timer, SRP, etc).
 968          * Powerdown must be optional, because of reset/DFU.
 969          */
 970 
 971         set_bit(port1, hub->change_bits);
 972         kick_hub_wq(hub);
 973 }
 974 
 975 /**
 976  * usb_remove_device - disable a device's port on its parent hub
 977  * @udev: device to be disabled and removed
 978  * Context: @udev locked, must be able to sleep.
 979  *
 980  * After @udev's port has been disabled, hub_wq is notified and it will
 981  * see that the device has been disconnected.  When the device is
 982  * physically unplugged and something is plugged in, the events will
 983  * be received and processed normally.
 984  *
 985  * Return: 0 if successful. A negative error code otherwise.
 986  */
 987 int usb_remove_device(struct usb_device *udev)
 988 {
 989         struct usb_hub *hub;
 990         struct usb_interface *intf;
 991         int ret;
 992 
 993         if (!udev->parent)      /* Can't remove a root hub */
 994                 return -EINVAL;
 995         hub = usb_hub_to_struct_hub(udev->parent);
 996         intf = to_usb_interface(hub->intfdev);
 997 
 998         ret = usb_autopm_get_interface(intf);
 999         if (ret < 0)
1000                 return ret;
1001 
1002         set_bit(udev->portnum, hub->removed_bits);
1003         hub_port_logical_disconnect(hub, udev->portnum);
1004         usb_autopm_put_interface(intf);
1005         return 0;
1006 }
1007 
1008 enum hub_activation_type {
1009         HUB_INIT, HUB_INIT2, HUB_INIT3,         /* INITs must come first */
1010         HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1011 };
1012 
1013 static void hub_init_func2(struct work_struct *ws);
1014 static void hub_init_func3(struct work_struct *ws);
1015 
1016 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1017 {
1018         struct usb_device *hdev = hub->hdev;
1019         struct usb_hcd *hcd;
1020         int ret;
1021         int port1;
1022         int status;
1023         bool need_debounce_delay = false;
1024         unsigned delay;
1025 
1026         /* Continue a partial initialization */
1027         if (type == HUB_INIT2 || type == HUB_INIT3) {
1028                 device_lock(&hdev->dev);
1029 
1030                 /* Was the hub disconnected while we were waiting? */
1031                 if (hub->disconnected)
1032                         goto disconnected;
1033                 if (type == HUB_INIT2)
1034                         goto init2;
1035                 goto init3;
1036         }
1037         kref_get(&hub->kref);
1038 
1039         /* The superspeed hub except for root hub has to use Hub Depth
1040          * value as an offset into the route string to locate the bits
1041          * it uses to determine the downstream port number. So hub driver
1042          * should send a set hub depth request to superspeed hub after
1043          * the superspeed hub is set configuration in initialization or
1044          * reset procedure.
1045          *
1046          * After a resume, port power should still be on.
1047          * For any other type of activation, turn it on.
1048          */
1049         if (type != HUB_RESUME) {
1050                 if (hdev->parent && hub_is_superspeed(hdev)) {
1051                         ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1052                                         HUB_SET_DEPTH, USB_RT_HUB,
1053                                         hdev->level - 1, 0, NULL, 0,
1054                                         USB_CTRL_SET_TIMEOUT);
1055                         if (ret < 0)
1056                                 dev_err(hub->intfdev,
1057                                                 "set hub depth failed\n");
1058                 }
1059 
1060                 /* Speed up system boot by using a delayed_work for the
1061                  * hub's initial power-up delays.  This is pretty awkward
1062                  * and the implementation looks like a home-brewed sort of
1063                  * setjmp/longjmp, but it saves at least 100 ms for each
1064                  * root hub (assuming usbcore is compiled into the kernel
1065                  * rather than as a module).  It adds up.
1066                  *
1067                  * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1068                  * because for those activation types the ports have to be
1069                  * operational when we return.  In theory this could be done
1070                  * for HUB_POST_RESET, but it's easier not to.
1071                  */
1072                 if (type == HUB_INIT) {
1073                         delay = hub_power_on_good_delay(hub);
1074 
1075                         hub_power_on(hub, false);
1076                         INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1077                         queue_delayed_work(system_power_efficient_wq,
1078                                         &hub->init_work,
1079                                         msecs_to_jiffies(delay));
1080 
1081                         /* Suppress autosuspend until init is done */
1082                         usb_autopm_get_interface_no_resume(
1083                                         to_usb_interface(hub->intfdev));
1084                         return;         /* Continues at init2: below */
1085                 } else if (type == HUB_RESET_RESUME) {
1086                         /* The internal host controller state for the hub device
1087                          * may be gone after a host power loss on system resume.
1088                          * Update the device's info so the HW knows it's a hub.
1089                          */
1090                         hcd = bus_to_hcd(hdev->bus);
1091                         if (hcd->driver->update_hub_device) {
1092                                 ret = hcd->driver->update_hub_device(hcd, hdev,
1093                                                 &hub->tt, GFP_NOIO);
1094                                 if (ret < 0) {
1095                                         dev_err(hub->intfdev,
1096                                                 "Host not accepting hub info update\n");
1097                                         dev_err(hub->intfdev,
1098                                                 "LS/FS devices and hubs may not work under this hub\n");
1099                                 }
1100                         }
1101                         hub_power_on(hub, true);
1102                 } else {
1103                         hub_power_on(hub, true);
1104                 }
1105         }
1106  init2:
1107 
1108         /*
1109          * Check each port and set hub->change_bits to let hub_wq know
1110          * which ports need attention.
1111          */
1112         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1113                 struct usb_port *port_dev = hub->ports[port1 - 1];
1114                 struct usb_device *udev = port_dev->child;
1115                 u16 portstatus, portchange;
1116 
1117                 portstatus = portchange = 0;
1118                 status = hub_port_status(hub, port1, &portstatus, &portchange);
1119                 if (status)
1120                         goto abort;
1121 
1122                 if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1123                         dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1124                                         portstatus, portchange);
1125 
1126                 /*
1127                  * After anything other than HUB_RESUME (i.e., initialization
1128                  * or any sort of reset), every port should be disabled.
1129                  * Unconnected ports should likewise be disabled (paranoia),
1130                  * and so should ports for which we have no usb_device.
1131                  */
1132                 if ((portstatus & USB_PORT_STAT_ENABLE) && (
1133                                 type != HUB_RESUME ||
1134                                 !(portstatus & USB_PORT_STAT_CONNECTION) ||
1135                                 !udev ||
1136                                 udev->state == USB_STATE_NOTATTACHED)) {
1137                         /*
1138                          * USB3 protocol ports will automatically transition
1139                          * to Enabled state when detect an USB3.0 device attach.
1140                          * Do not disable USB3 protocol ports, just pretend
1141                          * power was lost
1142                          */
1143                         portstatus &= ~USB_PORT_STAT_ENABLE;
1144                         if (!hub_is_superspeed(hdev))
1145                                 usb_clear_port_feature(hdev, port1,
1146                                                    USB_PORT_FEAT_ENABLE);
1147                 }
1148 
1149                 /* Make sure a warm-reset request is handled by port_event */
1150                 if (type == HUB_RESUME &&
1151                     hub_port_warm_reset_required(hub, port1, portstatus))
1152                         set_bit(port1, hub->event_bits);
1153 
1154                 /*
1155                  * Add debounce if USB3 link is in polling/link training state.
1156                  * Link will automatically transition to Enabled state after
1157                  * link training completes.
1158                  */
1159                 if (hub_is_superspeed(hdev) &&
1160                     ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1161                                                 USB_SS_PORT_LS_POLLING))
1162                         need_debounce_delay = true;
1163 
1164                 /* Clear status-change flags; we'll debounce later */
1165                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
1166                         need_debounce_delay = true;
1167                         usb_clear_port_feature(hub->hdev, port1,
1168                                         USB_PORT_FEAT_C_CONNECTION);
1169                 }
1170                 if (portchange & USB_PORT_STAT_C_ENABLE) {
1171                         need_debounce_delay = true;
1172                         usb_clear_port_feature(hub->hdev, port1,
1173                                         USB_PORT_FEAT_C_ENABLE);
1174                 }
1175                 if (portchange & USB_PORT_STAT_C_RESET) {
1176                         need_debounce_delay = true;
1177                         usb_clear_port_feature(hub->hdev, port1,
1178                                         USB_PORT_FEAT_C_RESET);
1179                 }
1180                 if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1181                                 hub_is_superspeed(hub->hdev)) {
1182                         need_debounce_delay = true;
1183                         usb_clear_port_feature(hub->hdev, port1,
1184                                         USB_PORT_FEAT_C_BH_PORT_RESET);
1185                 }
1186                 /* We can forget about a "removed" device when there's a
1187                  * physical disconnect or the connect status changes.
1188                  */
1189                 if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1190                                 (portchange & USB_PORT_STAT_C_CONNECTION))
1191                         clear_bit(port1, hub->removed_bits);
1192 
1193                 if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1194                         /* Tell hub_wq to disconnect the device or
1195                          * check for a new connection or over current condition.
1196                          * Based on USB2.0 Spec Section 11.12.5,
1197                          * C_PORT_OVER_CURRENT could be set while
1198                          * PORT_OVER_CURRENT is not. So check for any of them.
1199                          */
1200                         if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1201                             (portchange & USB_PORT_STAT_C_CONNECTION) ||
1202                             (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1203                             (portchange & USB_PORT_STAT_C_OVERCURRENT))
1204                                 set_bit(port1, hub->change_bits);
1205 
1206                 } else if (portstatus & USB_PORT_STAT_ENABLE) {
1207                         bool port_resumed = (portstatus &
1208                                         USB_PORT_STAT_LINK_STATE) ==
1209                                 USB_SS_PORT_LS_U0;
1210                         /* The power session apparently survived the resume.
1211                          * If there was an overcurrent or suspend change
1212                          * (i.e., remote wakeup request), have hub_wq
1213                          * take care of it.  Look at the port link state
1214                          * for USB 3.0 hubs, since they don't have a suspend
1215                          * change bit, and they don't set the port link change
1216                          * bit on device-initiated resume.
1217                          */
1218                         if (portchange || (hub_is_superspeed(hub->hdev) &&
1219                                                 port_resumed))
1220                                 set_bit(port1, hub->change_bits);
1221 
1222                 } else if (udev->persist_enabled) {
1223 #ifdef CONFIG_PM
1224                         udev->reset_resume = 1;
1225 #endif
1226                         /* Don't set the change_bits when the device
1227                          * was powered off.
1228                          */
1229                         if (test_bit(port1, hub->power_bits))
1230                                 set_bit(port1, hub->change_bits);
1231 
1232                 } else {
1233                         /* The power session is gone; tell hub_wq */
1234                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1235                         set_bit(port1, hub->change_bits);
1236                 }
1237         }
1238 
1239         /* If no port-status-change flags were set, we don't need any
1240          * debouncing.  If flags were set we can try to debounce the
1241          * ports all at once right now, instead of letting hub_wq do them
1242          * one at a time later on.
1243          *
1244          * If any port-status changes do occur during this delay, hub_wq
1245          * will see them later and handle them normally.
1246          */
1247         if (need_debounce_delay) {
1248                 delay = HUB_DEBOUNCE_STABLE;
1249 
1250                 /* Don't do a long sleep inside a workqueue routine */
1251                 if (type == HUB_INIT2) {
1252                         INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1253                         queue_delayed_work(system_power_efficient_wq,
1254                                         &hub->init_work,
1255                                         msecs_to_jiffies(delay));
1256                         device_unlock(&hdev->dev);
1257                         return;         /* Continues at init3: below */
1258                 } else {
1259                         msleep(delay);
1260                 }
1261         }
1262  init3:
1263         hub->quiescing = 0;
1264 
1265         status = usb_submit_urb(hub->urb, GFP_NOIO);
1266         if (status < 0)
1267                 dev_err(hub->intfdev, "activate --> %d\n", status);
1268         if (hub->has_indicators && blinkenlights)
1269                 queue_delayed_work(system_power_efficient_wq,
1270                                 &hub->leds, LED_CYCLE_PERIOD);
1271 
1272         /* Scan all ports that need attention */
1273         kick_hub_wq(hub);
1274  abort:
1275         if (type == HUB_INIT2 || type == HUB_INIT3) {
1276                 /* Allow autosuspend if it was suppressed */
1277  disconnected:
1278                 usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1279                 device_unlock(&hdev->dev);
1280         }
1281 
1282         kref_put(&hub->kref, hub_release);
1283 }
1284 
1285 /* Implement the continuations for the delays above */
1286 static void hub_init_func2(struct work_struct *ws)
1287 {
1288         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1289 
1290         hub_activate(hub, HUB_INIT2);
1291 }
1292 
1293 static void hub_init_func3(struct work_struct *ws)
1294 {
1295         struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1296 
1297         hub_activate(hub, HUB_INIT3);
1298 }
1299 
1300 enum hub_quiescing_type {
1301         HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1302 };
1303 
1304 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1305 {
1306         struct usb_device *hdev = hub->hdev;
1307         unsigned long flags;
1308         int i;
1309 
1310         /* hub_wq and related activity won't re-trigger */
1311         spin_lock_irqsave(&hub->irq_urb_lock, flags);
1312         hub->quiescing = 1;
1313         spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1314 
1315         if (type != HUB_SUSPEND) {
1316                 /* Disconnect all the children */
1317                 for (i = 0; i < hdev->maxchild; ++i) {
1318                         if (hub->ports[i]->child)
1319                                 usb_disconnect(&hub->ports[i]->child);
1320                 }
1321         }
1322 
1323         /* Stop hub_wq and related activity */
1324         del_timer_sync(&hub->irq_urb_retry);
1325         usb_kill_urb(hub->urb);
1326         if (hub->has_indicators)
1327                 cancel_delayed_work_sync(&hub->leds);
1328         if (hub->tt.hub)
1329                 flush_work(&hub->tt.clear_work);
1330 }
1331 
1332 static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1333 {
1334         int i;
1335 
1336         for (i = 0; i < hub->hdev->maxchild; ++i)
1337                 pm_runtime_barrier(&hub->ports[i]->dev);
1338 }
1339 
1340 /* caller has locked the hub device */
1341 static int hub_pre_reset(struct usb_interface *intf)
1342 {
1343         struct usb_hub *hub = usb_get_intfdata(intf);
1344 
1345         hub_quiesce(hub, HUB_PRE_RESET);
1346         hub->in_reset = 1;
1347         hub_pm_barrier_for_all_ports(hub);
1348         return 0;
1349 }
1350 
1351 /* caller has locked the hub device */
1352 static int hub_post_reset(struct usb_interface *intf)
1353 {
1354         struct usb_hub *hub = usb_get_intfdata(intf);
1355 
1356         hub->in_reset = 0;
1357         hub_pm_barrier_for_all_ports(hub);
1358         hub_activate(hub, HUB_POST_RESET);
1359         return 0;
1360 }
1361 
1362 static int hub_configure(struct usb_hub *hub,
1363         struct usb_endpoint_descriptor *endpoint)
1364 {
1365         struct usb_hcd *hcd;
1366         struct usb_device *hdev = hub->hdev;
1367         struct device *hub_dev = hub->intfdev;
1368         u16 hubstatus, hubchange;
1369         u16 wHubCharacteristics;
1370         unsigned int pipe;
1371         int maxp, ret, i;
1372         char *message = "out of memory";
1373         unsigned unit_load;
1374         unsigned full_load;
1375         unsigned maxchild;
1376 
1377         hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1378         if (!hub->buffer) {
1379                 ret = -ENOMEM;
1380                 goto fail;
1381         }
1382 
1383         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1384         if (!hub->status) {
1385                 ret = -ENOMEM;
1386                 goto fail;
1387         }
1388         mutex_init(&hub->status_mutex);
1389 
1390         hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1391         if (!hub->descriptor) {
1392                 ret = -ENOMEM;
1393                 goto fail;
1394         }
1395 
1396         /* Request the entire hub descriptor.
1397          * hub->descriptor can handle USB_MAXCHILDREN ports,
1398          * but a (non-SS) hub can/will return fewer bytes here.
1399          */
1400         ret = get_hub_descriptor(hdev, hub->descriptor);
1401         if (ret < 0) {
1402                 message = "can't read hub descriptor";
1403                 goto fail;
1404         }
1405 
1406         maxchild = USB_MAXCHILDREN;
1407         if (hub_is_superspeed(hdev))
1408                 maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1409 
1410         if (hub->descriptor->bNbrPorts > maxchild) {
1411                 message = "hub has too many ports!";
1412                 ret = -ENODEV;
1413                 goto fail;
1414         } else if (hub->descriptor->bNbrPorts == 0) {
1415                 message = "hub doesn't have any ports!";
1416                 ret = -ENODEV;
1417                 goto fail;
1418         }
1419 
1420         /*
1421          * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1422          * The resulting value will be used for SetIsochDelay() request.
1423          */
1424         if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1425                 u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1426 
1427                 if (hdev->parent)
1428                         delay += hdev->parent->hub_delay;
1429 
1430                 delay += USB_TP_TRANSMISSION_DELAY;
1431                 hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1432         }
1433 
1434         maxchild = hub->descriptor->bNbrPorts;
1435         dev_info(hub_dev, "%d port%s detected\n", maxchild,
1436                         (maxchild == 1) ? "" : "s");
1437 
1438         hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1439         if (!hub->ports) {
1440                 ret = -ENOMEM;
1441                 goto fail;
1442         }
1443 
1444         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1445         if (hub_is_superspeed(hdev)) {
1446                 unit_load = 150;
1447                 full_load = 900;
1448         } else {
1449                 unit_load = 100;
1450                 full_load = 500;
1451         }
1452 
1453         /* FIXME for USB 3.0, skip for now */
1454         if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1455                         !(hub_is_superspeed(hdev))) {
1456                 char    portstr[USB_MAXCHILDREN + 1];
1457 
1458                 for (i = 0; i < maxchild; i++)
1459                         portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1460                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1461                                 ? 'F' : 'R';
1462                 portstr[maxchild] = 0;
1463                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1464         } else
1465                 dev_dbg(hub_dev, "standalone hub\n");
1466 
1467         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1468         case HUB_CHAR_COMMON_LPSM:
1469                 dev_dbg(hub_dev, "ganged power switching\n");
1470                 break;
1471         case HUB_CHAR_INDV_PORT_LPSM:
1472                 dev_dbg(hub_dev, "individual port power switching\n");
1473                 break;
1474         case HUB_CHAR_NO_LPSM:
1475         case HUB_CHAR_LPSM:
1476                 dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1477                 break;
1478         }
1479 
1480         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1481         case HUB_CHAR_COMMON_OCPM:
1482                 dev_dbg(hub_dev, "global over-current protection\n");
1483                 break;
1484         case HUB_CHAR_INDV_PORT_OCPM:
1485                 dev_dbg(hub_dev, "individual port over-current protection\n");
1486                 break;
1487         case HUB_CHAR_NO_OCPM:
1488         case HUB_CHAR_OCPM:
1489                 dev_dbg(hub_dev, "no over-current protection\n");
1490                 break;
1491         }
1492 
1493         spin_lock_init(&hub->tt.lock);
1494         INIT_LIST_HEAD(&hub->tt.clear_list);
1495         INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1496         switch (hdev->descriptor.bDeviceProtocol) {
1497         case USB_HUB_PR_FS:
1498                 break;
1499         case USB_HUB_PR_HS_SINGLE_TT:
1500                 dev_dbg(hub_dev, "Single TT\n");
1501                 hub->tt.hub = hdev;
1502                 break;
1503         case USB_HUB_PR_HS_MULTI_TT:
1504                 ret = usb_set_interface(hdev, 0, 1);
1505                 if (ret == 0) {
1506                         dev_dbg(hub_dev, "TT per port\n");
1507                         hub->tt.multi = 1;
1508                 } else
1509                         dev_err(hub_dev, "Using single TT (err %d)\n",
1510                                 ret);
1511                 hub->tt.hub = hdev;
1512                 break;
1513         case USB_HUB_PR_SS:
1514                 /* USB 3.0 hubs don't have a TT */
1515                 break;
1516         default:
1517                 dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1518                         hdev->descriptor.bDeviceProtocol);
1519                 break;
1520         }
1521 
1522         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1523         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1524         case HUB_TTTT_8_BITS:
1525                 if (hdev->descriptor.bDeviceProtocol != 0) {
1526                         hub->tt.think_time = 666;
1527                         dev_dbg(hub_dev, "TT requires at most %d "
1528                                         "FS bit times (%d ns)\n",
1529                                 8, hub->tt.think_time);
1530                 }
1531                 break;
1532         case HUB_TTTT_16_BITS:
1533                 hub->tt.think_time = 666 * 2;
1534                 dev_dbg(hub_dev, "TT requires at most %d "
1535                                 "FS bit times (%d ns)\n",
1536                         16, hub->tt.think_time);
1537                 break;
1538         case HUB_TTTT_24_BITS:
1539                 hub->tt.think_time = 666 * 3;
1540                 dev_dbg(hub_dev, "TT requires at most %d "
1541                                 "FS bit times (%d ns)\n",
1542                         24, hub->tt.think_time);
1543                 break;
1544         case HUB_TTTT_32_BITS:
1545                 hub->tt.think_time = 666 * 4;
1546                 dev_dbg(hub_dev, "TT requires at most %d "
1547                                 "FS bit times (%d ns)\n",
1548                         32, hub->tt.think_time);
1549                 break;
1550         }
1551 
1552         /* probe() zeroes hub->indicator[] */
1553         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1554                 hub->has_indicators = 1;
1555                 dev_dbg(hub_dev, "Port indicators are supported\n");
1556         }
1557 
1558         dev_dbg(hub_dev, "power on to power good time: %dms\n",
1559                 hub->descriptor->bPwrOn2PwrGood * 2);
1560 
1561         /* power budgeting mostly matters with bus-powered hubs,
1562          * and battery-powered root hubs (may provide just 8 mA).
1563          */
1564         ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1565         if (ret) {
1566                 message = "can't get hub status";
1567                 goto fail;
1568         }
1569         hcd = bus_to_hcd(hdev->bus);
1570         if (hdev == hdev->bus->root_hub) {
1571                 if (hcd->power_budget > 0)
1572                         hdev->bus_mA = hcd->power_budget;
1573                 else
1574                         hdev->bus_mA = full_load * maxchild;
1575                 if (hdev->bus_mA >= full_load)
1576                         hub->mA_per_port = full_load;
1577                 else {
1578                         hub->mA_per_port = hdev->bus_mA;
1579                         hub->limited_power = 1;
1580                 }
1581         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1582                 int remaining = hdev->bus_mA -
1583                         hub->descriptor->bHubContrCurrent;
1584 
1585                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1586                         hub->descriptor->bHubContrCurrent);
1587                 hub->limited_power = 1;
1588 
1589                 if (remaining < maxchild * unit_load)
1590                         dev_warn(hub_dev,
1591                                         "insufficient power available "
1592                                         "to use all downstream ports\n");
1593                 hub->mA_per_port = unit_load;   /* 7.2.1 */
1594 
1595         } else {        /* Self-powered external hub */
1596                 /* FIXME: What about battery-powered external hubs that
1597                  * provide less current per port? */
1598                 hub->mA_per_port = full_load;
1599         }
1600         if (hub->mA_per_port < full_load)
1601                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1602                                 hub->mA_per_port);
1603 
1604         ret = hub_hub_status(hub, &hubstatus, &hubchange);
1605         if (ret < 0) {
1606                 message = "can't get hub status";
1607                 goto fail;
1608         }
1609 
1610         /* local power status reports aren't always correct */
1611         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1612                 dev_dbg(hub_dev, "local power source is %s\n",
1613                         (hubstatus & HUB_STATUS_LOCAL_POWER)
1614                         ? "lost (inactive)" : "good");
1615 
1616         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1617                 dev_dbg(hub_dev, "%sover-current condition exists\n",
1618                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1619 
1620         /* set up the interrupt endpoint
1621          * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1622          * bytes as USB2.0[11.12.3] says because some hubs are known
1623          * to send more data (and thus cause overflow). For root hubs,
1624          * maxpktsize is defined in hcd.c's fake endpoint descriptors
1625          * to be big enough for at least USB_MAXCHILDREN ports. */
1626         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1627         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
1628 
1629         if (maxp > sizeof(*hub->buffer))
1630                 maxp = sizeof(*hub->buffer);
1631 
1632         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1633         if (!hub->urb) {
1634                 ret = -ENOMEM;
1635                 goto fail;
1636         }
1637 
1638         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1639                 hub, endpoint->bInterval);
1640 
1641         /* maybe cycle the hub leds */
1642         if (hub->has_indicators && blinkenlights)
1643                 hub->indicator[0] = INDICATOR_CYCLE;
1644 
1645         mutex_lock(&usb_port_peer_mutex);
1646         for (i = 0; i < maxchild; i++) {
1647                 ret = usb_hub_create_port_device(hub, i + 1);
1648                 if (ret < 0) {
1649                         dev_err(hub->intfdev,
1650                                 "couldn't create port%d device.\n", i + 1);
1651                         break;
1652                 }
1653         }
1654         hdev->maxchild = i;
1655         for (i = 0; i < hdev->maxchild; i++) {
1656                 struct usb_port *port_dev = hub->ports[i];
1657 
1658                 pm_runtime_put(&port_dev->dev);
1659         }
1660 
1661         mutex_unlock(&usb_port_peer_mutex);
1662         if (ret < 0)
1663                 goto fail;
1664 
1665         /* Update the HCD's internal representation of this hub before hub_wq
1666          * starts getting port status changes for devices under the hub.
1667          */
1668         if (hcd->driver->update_hub_device) {
1669                 ret = hcd->driver->update_hub_device(hcd, hdev,
1670                                 &hub->tt, GFP_KERNEL);
1671                 if (ret < 0) {
1672                         message = "can't update HCD hub info";
1673                         goto fail;
1674                 }
1675         }
1676 
1677         usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1678 
1679         hub_activate(hub, HUB_INIT);
1680         return 0;
1681 
1682 fail:
1683         dev_err(hub_dev, "config failed, %s (err %d)\n",
1684                         message, ret);
1685         /* hub_disconnect() frees urb and descriptor */
1686         return ret;
1687 }
1688 
1689 static void hub_release(struct kref *kref)
1690 {
1691         struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1692 
1693         usb_put_dev(hub->hdev);
1694         usb_put_intf(to_usb_interface(hub->intfdev));
1695         kfree(hub);
1696 }
1697 
1698 static unsigned highspeed_hubs;
1699 
1700 static void hub_disconnect(struct usb_interface *intf)
1701 {
1702         struct usb_hub *hub = usb_get_intfdata(intf);
1703         struct usb_device *hdev = interface_to_usbdev(intf);
1704         int port1;
1705 
1706         /*
1707          * Stop adding new hub events. We do not want to block here and thus
1708          * will not try to remove any pending work item.
1709          */
1710         hub->disconnected = 1;
1711 
1712         /* Disconnect all children and quiesce the hub */
1713         hub->error = 0;
1714         hub_quiesce(hub, HUB_DISCONNECT);
1715 
1716         mutex_lock(&usb_port_peer_mutex);
1717 
1718         /* Avoid races with recursively_mark_NOTATTACHED() */
1719         spin_lock_irq(&device_state_lock);
1720         port1 = hdev->maxchild;
1721         hdev->maxchild = 0;
1722         usb_set_intfdata(intf, NULL);
1723         spin_unlock_irq(&device_state_lock);
1724 
1725         for (; port1 > 0; --port1)
1726                 usb_hub_remove_port_device(hub, port1);
1727 
1728         mutex_unlock(&usb_port_peer_mutex);
1729 
1730         if (hub->hdev->speed == USB_SPEED_HIGH)
1731                 highspeed_hubs--;
1732 
1733         usb_free_urb(hub->urb);
1734         kfree(hub->ports);
1735         kfree(hub->descriptor);
1736         kfree(hub->status);
1737         kfree(hub->buffer);
1738 
1739         pm_suspend_ignore_children(&intf->dev, false);
1740 
1741         if (hub->quirk_disable_autosuspend)
1742                 usb_autopm_put_interface(intf);
1743 
1744         kref_put(&hub->kref, hub_release);
1745 }
1746 
1747 static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1748 {
1749         /* Some hubs have a subclass of 1, which AFAICT according to the */
1750         /*  specs is not defined, but it works */
1751         if (desc->desc.bInterfaceSubClass != 0 &&
1752             desc->desc.bInterfaceSubClass != 1)
1753                 return false;
1754 
1755         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
1756         if (desc->desc.bNumEndpoints != 1)
1757                 return false;
1758 
1759         /* If the first endpoint is not interrupt IN, we'd better punt! */
1760         if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1761                 return false;
1762 
1763         return true;
1764 }
1765 
1766 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1767 {
1768         struct usb_host_interface *desc;
1769         struct usb_device *hdev;
1770         struct usb_hub *hub;
1771 
1772         desc = intf->cur_altsetting;
1773         hdev = interface_to_usbdev(intf);
1774 
1775         /*
1776          * Set default autosuspend delay as 0 to speedup bus suspend,
1777          * based on the below considerations:
1778          *
1779          * - Unlike other drivers, the hub driver does not rely on the
1780          *   autosuspend delay to provide enough time to handle a wakeup
1781          *   event, and the submitted status URB is just to check future
1782          *   change on hub downstream ports, so it is safe to do it.
1783          *
1784          * - The patch might cause one or more auto supend/resume for
1785          *   below very rare devices when they are plugged into hub
1786          *   first time:
1787          *
1788          *      devices having trouble initializing, and disconnect
1789          *      themselves from the bus and then reconnect a second
1790          *      or so later
1791          *
1792          *      devices just for downloading firmware, and disconnects
1793          *      themselves after completing it
1794          *
1795          *   For these quite rare devices, their drivers may change the
1796          *   autosuspend delay of their parent hub in the probe() to one
1797          *   appropriate value to avoid the subtle problem if someone
1798          *   does care it.
1799          *
1800          * - The patch may cause one or more auto suspend/resume on
1801          *   hub during running 'lsusb', but it is probably too
1802          *   infrequent to worry about.
1803          *
1804          * - Change autosuspend delay of hub can avoid unnecessary auto
1805          *   suspend timer for hub, also may decrease power consumption
1806          *   of USB bus.
1807          *
1808          * - If user has indicated to prevent autosuspend by passing
1809          *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1810          */
1811 #ifdef CONFIG_PM
1812         if (hdev->dev.power.autosuspend_delay >= 0)
1813                 pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1814 #endif
1815 
1816         /*
1817          * Hubs have proper suspend/resume support, except for root hubs
1818          * where the controller driver doesn't have bus_suspend and
1819          * bus_resume methods.
1820          */
1821         if (hdev->parent) {             /* normal device */
1822                 usb_enable_autosuspend(hdev);
1823         } else {                        /* root hub */
1824                 const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1825 
1826                 if (drv->bus_suspend && drv->bus_resume)
1827                         usb_enable_autosuspend(hdev);
1828         }
1829 
1830         if (hdev->level == MAX_TOPO_LEVEL) {
1831                 dev_err(&intf->dev,
1832                         "Unsupported bus topology: hub nested too deep\n");
1833                 return -E2BIG;
1834         }
1835 
1836 #ifdef  CONFIG_USB_OTG_BLACKLIST_HUB
1837         if (hdev->parent) {
1838                 dev_warn(&intf->dev, "ignoring external hub\n");
1839                 return -ENODEV;
1840         }
1841 #endif
1842 
1843         if (!hub_descriptor_is_sane(desc)) {
1844                 dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1845                 return -EIO;
1846         }
1847 
1848         /* We found a hub */
1849         dev_info(&intf->dev, "USB hub found\n");
1850 
1851         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1852         if (!hub)
1853                 return -ENOMEM;
1854 
1855         kref_init(&hub->kref);
1856         hub->intfdev = &intf->dev;
1857         hub->hdev = hdev;
1858         INIT_DELAYED_WORK(&hub->leds, led_work);
1859         INIT_DELAYED_WORK(&hub->init_work, NULL);
1860         INIT_WORK(&hub->events, hub_event);
1861         spin_lock_init(&hub->irq_urb_lock);
1862         timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1863         usb_get_intf(intf);
1864         usb_get_dev(hdev);
1865 
1866         usb_set_intfdata(intf, hub);
1867         intf->needs_remote_wakeup = 1;
1868         pm_suspend_ignore_children(&intf->dev, true);
1869 
1870         if (hdev->speed == USB_SPEED_HIGH)
1871                 highspeed_hubs++;
1872 
1873         if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1874                 hub->quirk_check_port_auto_suspend = 1;
1875 
1876         if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
1877                 hub->quirk_disable_autosuspend = 1;
1878                 usb_autopm_get_interface_no_resume(intf);
1879         }
1880 
1881         if (hub_configure(hub, &desc->endpoint[0].desc) >= 0)
1882                 return 0;
1883 
1884         hub_disconnect(intf);
1885         return -ENODEV;
1886 }
1887 
1888 static int
1889 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1890 {
1891         struct usb_device *hdev = interface_to_usbdev(intf);
1892         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1893 
1894         /* assert ifno == 0 (part of hub spec) */
1895         switch (code) {
1896         case USBDEVFS_HUB_PORTINFO: {
1897                 struct usbdevfs_hub_portinfo *info = user_data;
1898                 int i;
1899 
1900                 spin_lock_irq(&device_state_lock);
1901                 if (hdev->devnum <= 0)
1902                         info->nports = 0;
1903                 else {
1904                         info->nports = hdev->maxchild;
1905                         for (i = 0; i < info->nports; i++) {
1906                                 if (hub->ports[i]->child == NULL)
1907                                         info->port[i] = 0;
1908                                 else
1909                                         info->port[i] =
1910                                                 hub->ports[i]->child->devnum;
1911                         }
1912                 }
1913                 spin_unlock_irq(&device_state_lock);
1914 
1915                 return info->nports + 1;
1916                 }
1917 
1918         default:
1919                 return -ENOSYS;
1920         }
1921 }
1922 
1923 /*
1924  * Allow user programs to claim ports on a hub.  When a device is attached
1925  * to one of these "claimed" ports, the program will "own" the device.
1926  */
1927 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1928                 struct usb_dev_state ***ppowner)
1929 {
1930         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1931 
1932         if (hdev->state == USB_STATE_NOTATTACHED)
1933                 return -ENODEV;
1934         if (port1 == 0 || port1 > hdev->maxchild)
1935                 return -EINVAL;
1936 
1937         /* Devices not managed by the hub driver
1938          * will always have maxchild equal to 0.
1939          */
1940         *ppowner = &(hub->ports[port1 - 1]->port_owner);
1941         return 0;
1942 }
1943 
1944 /* In the following three functions, the caller must hold hdev's lock */
1945 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1946                        struct usb_dev_state *owner)
1947 {
1948         int rc;
1949         struct usb_dev_state **powner;
1950 
1951         rc = find_port_owner(hdev, port1, &powner);
1952         if (rc)
1953                 return rc;
1954         if (*powner)
1955                 return -EBUSY;
1956         *powner = owner;
1957         return rc;
1958 }
1959 EXPORT_SYMBOL_GPL(usb_hub_claim_port);
1960 
1961 int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
1962                          struct usb_dev_state *owner)
1963 {
1964         int rc;
1965         struct usb_dev_state **powner;
1966 
1967         rc = find_port_owner(hdev, port1, &powner);
1968         if (rc)
1969                 return rc;
1970         if (*powner != owner)
1971                 return -ENOENT;
1972         *powner = NULL;
1973         return rc;
1974 }
1975 EXPORT_SYMBOL_GPL(usb_hub_release_port);
1976 
1977 void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
1978 {
1979         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1980         int n;
1981 
1982         for (n = 0; n < hdev->maxchild; n++) {
1983                 if (hub->ports[n]->port_owner == owner)
1984                         hub->ports[n]->port_owner = NULL;
1985         }
1986 
1987 }
1988 
1989 /* The caller must hold udev's lock */
1990 bool usb_device_is_owned(struct usb_device *udev)
1991 {
1992         struct usb_hub *hub;
1993 
1994         if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
1995                 return false;
1996         hub = usb_hub_to_struct_hub(udev->parent);
1997         return !!hub->ports[udev->portnum - 1]->port_owner;
1998 }
1999 
2000 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
2001 {
2002         struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2003         int i;
2004 
2005         for (i = 0; i < udev->maxchild; ++i) {
2006                 if (hub->ports[i]->child)
2007                         recursively_mark_NOTATTACHED(hub->ports[i]->child);
2008         }
2009         if (udev->state == USB_STATE_SUSPENDED)
2010                 udev->active_duration -= jiffies;
2011         udev->state = USB_STATE_NOTATTACHED;
2012 }
2013 
2014 /**
2015  * usb_set_device_state - change a device's current state (usbcore, hcds)
2016  * @udev: pointer to device whose state should be changed
2017  * @new_state: new state value to be stored
2018  *
2019  * udev->state is _not_ fully protected by the device lock.  Although
2020  * most transitions are made only while holding the lock, the state can
2021  * can change to USB_STATE_NOTATTACHED at almost any time.  This
2022  * is so that devices can be marked as disconnected as soon as possible,
2023  * without having to wait for any semaphores to be released.  As a result,
2024  * all changes to any device's state must be protected by the
2025  * device_state_lock spinlock.
2026  *
2027  * Once a device has been added to the device tree, all changes to its state
2028  * should be made using this routine.  The state should _not_ be set directly.
2029  *
2030  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2031  * Otherwise udev->state is set to new_state, and if new_state is
2032  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2033  * to USB_STATE_NOTATTACHED.
2034  */
2035 void usb_set_device_state(struct usb_device *udev,
2036                 enum usb_device_state new_state)
2037 {
2038         unsigned long flags;
2039         int wakeup = -1;
2040 
2041         spin_lock_irqsave(&device_state_lock, flags);
2042         if (udev->state == USB_STATE_NOTATTACHED)
2043                 ;       /* do nothing */
2044         else if (new_state != USB_STATE_NOTATTACHED) {
2045 
2046                 /* root hub wakeup capabilities are managed out-of-band
2047                  * and may involve silicon errata ... ignore them here.
2048                  */
2049                 if (udev->parent) {
2050                         if (udev->state == USB_STATE_SUSPENDED
2051                                         || new_state == USB_STATE_SUSPENDED)
2052                                 ;       /* No change to wakeup settings */
2053                         else if (new_state == USB_STATE_CONFIGURED)
2054                                 wakeup = (udev->quirks &
2055                                         USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2056                                         udev->actconfig->desc.bmAttributes &
2057                                         USB_CONFIG_ATT_WAKEUP;
2058                         else
2059                                 wakeup = 0;
2060                 }
2061                 if (udev->state == USB_STATE_SUSPENDED &&
2062                         new_state != USB_STATE_SUSPENDED)
2063                         udev->active_duration -= jiffies;
2064                 else if (new_state == USB_STATE_SUSPENDED &&
2065                                 udev->state != USB_STATE_SUSPENDED)
2066                         udev->active_duration += jiffies;
2067                 udev->state = new_state;
2068         } else
2069                 recursively_mark_NOTATTACHED(udev);
2070         spin_unlock_irqrestore(&device_state_lock, flags);
2071         if (wakeup >= 0)
2072                 device_set_wakeup_capable(&udev->dev, wakeup);
2073 }
2074 EXPORT_SYMBOL_GPL(usb_set_device_state);
2075 
2076 /*
2077  * Choose a device number.
2078  *
2079  * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2080  * USB-2.0 buses they are also used as device addresses, however on
2081  * USB-3.0 buses the address is assigned by the controller hardware
2082  * and it usually is not the same as the device number.
2083  *
2084  * WUSB devices are simple: they have no hubs behind, so the mapping
2085  * device <-> virtual port number becomes 1:1. Why? to simplify the
2086  * life of the device connection logic in
2087  * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
2088  * handshake we need to assign a temporary address in the unauthorized
2089  * space. For simplicity we use the first virtual port number found to
2090  * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
2091  * and that becomes it's address [X < 128] or its unauthorized address
2092  * [X | 0x80].
2093  *
2094  * We add 1 as an offset to the one-based USB-stack port number
2095  * (zero-based wusb virtual port index) for two reasons: (a) dev addr
2096  * 0 is reserved by USB for default address; (b) Linux's USB stack
2097  * uses always #1 for the root hub of the controller. So USB stack's
2098  * port #1, which is wusb virtual-port #0 has address #2.
2099  *
2100  * Devices connected under xHCI are not as simple.  The host controller
2101  * supports virtualization, so the hardware assigns device addresses and
2102  * the HCD must setup data structures before issuing a set address
2103  * command to the hardware.
2104  */
2105 static void choose_devnum(struct usb_device *udev)
2106 {
2107         int             devnum;
2108         struct usb_bus  *bus = udev->bus;
2109 
2110         /* be safe when more hub events are proceed in parallel */
2111         mutex_lock(&bus->devnum_next_mutex);
2112         if (udev->wusb) {
2113                 devnum = udev->portnum + 1;
2114                 BUG_ON(test_bit(devnum, bus->devmap.devicemap));
2115         } else {
2116                 /* Try to allocate the next devnum beginning at
2117                  * bus->devnum_next. */
2118                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2119                                             bus->devnum_next);
2120                 if (devnum >= 128)
2121                         devnum = find_next_zero_bit(bus->devmap.devicemap,
2122                                                     128, 1);
2123                 bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2124         }
2125         if (devnum < 128) {
2126                 set_bit(devnum, bus->devmap.devicemap);
2127                 udev->devnum = devnum;
2128         }
2129         mutex_unlock(&bus->devnum_next_mutex);
2130 }
2131 
2132 static void release_devnum(struct usb_device *udev)
2133 {
2134         if (udev->devnum > 0) {
2135                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2136                 udev->devnum = -1;
2137         }
2138 }
2139 
2140 static void update_devnum(struct usb_device *udev, int devnum)
2141 {
2142         /* The address for a WUSB device is managed by wusbcore. */
2143         if (!udev->wusb)
2144                 udev->devnum = devnum;
2145         if (!udev->devaddr)
2146                 udev->devaddr = (u8)devnum;
2147 }
2148 
2149 static void hub_free_dev(struct usb_device *udev)
2150 {
2151         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2152 
2153         /* Root hubs aren't real devices, so don't free HCD resources */
2154         if (hcd->driver->free_dev && udev->parent)
2155                 hcd->driver->free_dev(hcd, udev);
2156 }
2157 
2158 static void hub_disconnect_children(struct usb_device *udev)
2159 {
2160         struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2161         int i;
2162 
2163         /* Free up all the children before we remove this device */
2164         for (i = 0; i < udev->maxchild; i++) {
2165                 if (hub->ports[i]->child)
2166                         usb_disconnect(&hub->ports[i]->child);
2167         }
2168 }
2169 
2170 /**
2171  * usb_disconnect - disconnect a device (usbcore-internal)
2172  * @pdev: pointer to device being disconnected
2173  * Context: !in_interrupt ()
2174  *
2175  * Something got disconnected. Get rid of it and all of its children.
2176  *
2177  * If *pdev is a normal device then the parent hub must already be locked.
2178  * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2179  * which protects the set of root hubs as well as the list of buses.
2180  *
2181  * Only hub drivers (including virtual root hub drivers for host
2182  * controllers) should ever call this.
2183  *
2184  * This call is synchronous, and may not be used in an interrupt context.
2185  */
2186 void usb_disconnect(struct usb_device **pdev)
2187 {
2188         struct usb_port *port_dev = NULL;
2189         struct usb_device *udev = *pdev;
2190         struct usb_hub *hub = NULL;
2191         int port1 = 1;
2192 
2193         /* mark the device as inactive, so any further urb submissions for
2194          * this device (and any of its children) will fail immediately.
2195          * this quiesces everything except pending urbs.
2196          */
2197         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2198         dev_info(&udev->dev, "USB disconnect, device number %d\n",
2199                         udev->devnum);
2200 
2201         /*
2202          * Ensure that the pm runtime code knows that the USB device
2203          * is in the process of being disconnected.
2204          */
2205         pm_runtime_barrier(&udev->dev);
2206 
2207         usb_lock_device(udev);
2208 
2209         hub_disconnect_children(udev);
2210 
2211         /* deallocate hcd/hardware state ... nuking all pending urbs and
2212          * cleaning up all state associated with the current configuration
2213          * so that the hardware is now fully quiesced.
2214          */
2215         dev_dbg(&udev->dev, "unregistering device\n");
2216         usb_disable_device(udev, 0);
2217         usb_hcd_synchronize_unlinks(udev);
2218 
2219         if (udev->parent) {
2220                 port1 = udev->portnum;
2221                 hub = usb_hub_to_struct_hub(udev->parent);
2222                 port_dev = hub->ports[port1 - 1];
2223 
2224                 sysfs_remove_link(&udev->dev.kobj, "port");
2225                 sysfs_remove_link(&port_dev->dev.kobj, "device");
2226 
2227                 /*
2228                  * As usb_port_runtime_resume() de-references udev, make
2229                  * sure no resumes occur during removal
2230                  */
2231                 if (!test_and_set_bit(port1, hub->child_usage_bits))
2232                         pm_runtime_get_sync(&port_dev->dev);
2233         }
2234 
2235         usb_remove_ep_devs(&udev->ep0);
2236         usb_unlock_device(udev);
2237 
2238         /* Unregister the device.  The device driver is responsible
2239          * for de-configuring the device and invoking the remove-device
2240          * notifier chain (used by usbfs and possibly others).
2241          */
2242         device_del(&udev->dev);
2243 
2244         /* Free the device number and delete the parent's children[]
2245          * (or root_hub) pointer.
2246          */
2247         release_devnum(udev);
2248 
2249         /* Avoid races with recursively_mark_NOTATTACHED() */
2250         spin_lock_irq(&device_state_lock);
2251         *pdev = NULL;
2252         spin_unlock_irq(&device_state_lock);
2253 
2254         if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2255                 pm_runtime_put(&port_dev->dev);
2256 
2257         hub_free_dev(udev);
2258 
2259         put_device(&udev->dev);
2260 }
2261 
2262 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2263 static void show_string(struct usb_device *udev, char *id, char *string)
2264 {
2265         if (!string)
2266                 return;
2267         dev_info(&udev->dev, "%s: %s\n", id, string);
2268 }
2269 
2270 static void announce_device(struct usb_device *udev)
2271 {
2272         u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2273 
2274         dev_info(&udev->dev,
2275                 "New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2276                 le16_to_cpu(udev->descriptor.idVendor),
2277                 le16_to_cpu(udev->descriptor.idProduct),
2278                 bcdDevice >> 8, bcdDevice & 0xff);
2279         dev_info(&udev->dev,
2280                 "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2281                 udev->descriptor.iManufacturer,
2282                 udev->descriptor.iProduct,
2283                 udev->descriptor.iSerialNumber);
2284         show_string(udev, "Product", udev->product);
2285         show_string(udev, "Manufacturer", udev->manufacturer);
2286         show_string(udev, "SerialNumber", udev->serial);
2287 }
2288 #else
2289 static inline void announce_device(struct usb_device *udev) { }
2290 #endif
2291 
2292 
2293 /**
2294  * usb_enumerate_device_otg - FIXME (usbcore-internal)
2295  * @udev: newly addressed device (in ADDRESS state)
2296  *
2297  * Finish enumeration for On-The-Go devices
2298  *
2299  * Return: 0 if successful. A negative error code otherwise.
2300  */
2301 static int usb_enumerate_device_otg(struct usb_device *udev)
2302 {
2303         int err = 0;
2304 
2305 #ifdef  CONFIG_USB_OTG
2306         /*
2307          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2308          * to wake us after we've powered off VBUS; and HNP, switching roles
2309          * "host" to "peripheral".  The OTG descriptor helps figure this out.
2310          */
2311         if (!udev->bus->is_b_host
2312                         && udev->config
2313                         && udev->parent == udev->bus->root_hub) {
2314                 struct usb_otg_descriptor       *desc = NULL;
2315                 struct usb_bus                  *bus = udev->bus;
2316                 unsigned                        port1 = udev->portnum;
2317 
2318                 /* descriptor may appear anywhere in config */
2319                 err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2320                                 le16_to_cpu(udev->config[0].desc.wTotalLength),
2321                                 USB_DT_OTG, (void **) &desc, sizeof(*desc));
2322                 if (err || !(desc->bmAttributes & USB_OTG_HNP))
2323                         return 0;
2324 
2325                 dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2326                                         (port1 == bus->otg_port) ? "" : "non-");
2327 
2328                 /* enable HNP before suspend, it's simpler */
2329                 if (port1 == bus->otg_port) {
2330                         bus->b_hnp_enable = 1;
2331                         err = usb_control_msg(udev,
2332                                 usb_sndctrlpipe(udev, 0),
2333                                 USB_REQ_SET_FEATURE, 0,
2334                                 USB_DEVICE_B_HNP_ENABLE,
2335                                 0, NULL, 0,
2336                                 USB_CTRL_SET_TIMEOUT);
2337                         if (err < 0) {
2338                                 /*
2339                                  * OTG MESSAGE: report errors here,
2340                                  * customize to match your product.
2341                                  */
2342                                 dev_err(&udev->dev, "can't set HNP mode: %d\n",
2343                                                                         err);
2344                                 bus->b_hnp_enable = 0;
2345                         }
2346                 } else if (desc->bLength == sizeof
2347                                 (struct usb_otg_descriptor)) {
2348                         /* Set a_alt_hnp_support for legacy otg device */
2349                         err = usb_control_msg(udev,
2350                                 usb_sndctrlpipe(udev, 0),
2351                                 USB_REQ_SET_FEATURE, 0,
2352                                 USB_DEVICE_A_ALT_HNP_SUPPORT,
2353                                 0, NULL, 0,
2354                                 USB_CTRL_SET_TIMEOUT);
2355                         if (err < 0)
2356                                 dev_err(&udev->dev,
2357                                         "set a_alt_hnp_support failed: %d\n",
2358                                         err);
2359                 }
2360         }
2361 #endif
2362         return err;
2363 }
2364 
2365 
2366 /**
2367  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2368  * @udev: newly addressed device (in ADDRESS state)
2369  *
2370  * This is only called by usb_new_device() and usb_authorize_device()
2371  * and FIXME -- all comments that apply to them apply here wrt to
2372  * environment.
2373  *
2374  * If the device is WUSB and not authorized, we don't attempt to read
2375  * the string descriptors, as they will be errored out by the device
2376  * until it has been authorized.
2377  *
2378  * Return: 0 if successful. A negative error code otherwise.
2379  */
2380 static int usb_enumerate_device(struct usb_device *udev)
2381 {
2382         int err;
2383         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2384 
2385         if (udev->config == NULL) {
2386                 err = usb_get_configuration(udev);
2387                 if (err < 0) {
2388                         if (err != -ENODEV)
2389                                 dev_err(&udev->dev, "can't read configurations, error %d\n",
2390                                                 err);
2391                         return err;
2392                 }
2393         }
2394 
2395         /* read the standard strings and cache them if present */
2396         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2397         udev->manufacturer = usb_cache_string(udev,
2398                                               udev->descriptor.iManufacturer);
2399         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2400 
2401         err = usb_enumerate_device_otg(udev);
2402         if (err < 0)
2403                 return err;
2404 
2405         if (IS_ENABLED(CONFIG_USB_OTG_WHITELIST) && hcd->tpl_support &&
2406                 !is_targeted(udev)) {
2407                 /* Maybe it can talk to us, though we can't talk to it.
2408                  * (Includes HNP test device.)
2409                  */
2410                 if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2411                         || udev->bus->is_b_host)) {
2412                         err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2413                         if (err < 0)
2414                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2415                 }
2416                 return -ENOTSUPP;
2417         }
2418 
2419         usb_detect_interface_quirks(udev);
2420 
2421         return 0;
2422 }
2423 
2424 static void set_usb_port_removable(struct usb_device *udev)
2425 {
2426         struct usb_device *hdev = udev->parent;
2427         struct usb_hub *hub;
2428         u8 port = udev->portnum;
2429         u16 wHubCharacteristics;
2430         bool removable = true;
2431 
2432         if (!hdev)
2433                 return;
2434 
2435         hub = usb_hub_to_struct_hub(udev->parent);
2436 
2437         /*
2438          * If the platform firmware has provided information about a port,
2439          * use that to determine whether it's removable.
2440          */
2441         switch (hub->ports[udev->portnum - 1]->connect_type) {
2442         case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2443                 udev->removable = USB_DEVICE_REMOVABLE;
2444                 return;
2445         case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2446         case USB_PORT_NOT_USED:
2447                 udev->removable = USB_DEVICE_FIXED;
2448                 return;
2449         default:
2450                 break;
2451         }
2452 
2453         /*
2454          * Otherwise, check whether the hub knows whether a port is removable
2455          * or not
2456          */
2457         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2458 
2459         if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2460                 return;
2461 
2462         if (hub_is_superspeed(hdev)) {
2463                 if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2464                                 & (1 << port))
2465                         removable = false;
2466         } else {
2467                 if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2468                         removable = false;
2469         }
2470 
2471         if (removable)
2472                 udev->removable = USB_DEVICE_REMOVABLE;
2473         else
2474                 udev->removable = USB_DEVICE_FIXED;
2475 
2476 }
2477 
2478 /**
2479  * usb_new_device - perform initial device setup (usbcore-internal)
2480  * @udev: newly addressed device (in ADDRESS state)
2481  *
2482  * This is called with devices which have been detected but not fully
2483  * enumerated.  The device descriptor is available, but not descriptors
2484  * for any device configuration.  The caller must have locked either
2485  * the parent hub (if udev is a normal device) or else the
2486  * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2487  * udev has already been installed, but udev is not yet visible through
2488  * sysfs or other filesystem code.
2489  *
2490  * This call is synchronous, and may not be used in an interrupt context.
2491  *
2492  * Only the hub driver or root-hub registrar should ever call this.
2493  *
2494  * Return: Whether the device is configured properly or not. Zero if the
2495  * interface was registered with the driver core; else a negative errno
2496  * value.
2497  *
2498  */
2499 int usb_new_device(struct usb_device *udev)
2500 {
2501         int err;
2502 
2503         if (udev->parent) {
2504                 /* Initialize non-root-hub device wakeup to disabled;
2505                  * device (un)configuration controls wakeup capable
2506                  * sysfs power/wakeup controls wakeup enabled/disabled
2507                  */
2508                 device_init_wakeup(&udev->dev, 0);
2509         }
2510 
2511         /* Tell the runtime-PM framework the device is active */
2512         pm_runtime_set_active(&udev->dev);
2513         pm_runtime_get_noresume(&udev->dev);
2514         pm_runtime_use_autosuspend(&udev->dev);
2515         pm_runtime_enable(&udev->dev);
2516 
2517         /* By default, forbid autosuspend for all devices.  It will be
2518          * allowed for hubs during binding.
2519          */
2520         usb_disable_autosuspend(udev);
2521 
2522         err = usb_enumerate_device(udev);       /* Read descriptors */
2523         if (err < 0)
2524                 goto fail;
2525         dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2526                         udev->devnum, udev->bus->busnum,
2527                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2528         /* export the usbdev device-node for libusb */
2529         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2530                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2531 
2532         /* Tell the world! */
2533         announce_device(udev);
2534 
2535         if (udev->serial)
2536                 add_device_randomness(udev->serial, strlen(udev->serial));
2537         if (udev->product)
2538                 add_device_randomness(udev->product, strlen(udev->product));
2539         if (udev->manufacturer)
2540                 add_device_randomness(udev->manufacturer,
2541                                       strlen(udev->manufacturer));
2542 
2543         device_enable_async_suspend(&udev->dev);
2544 
2545         /* check whether the hub or firmware marks this port as non-removable */
2546         if (udev->parent)
2547                 set_usb_port_removable(udev);
2548 
2549         /* Register the device.  The device driver is responsible
2550          * for configuring the device and invoking the add-device
2551          * notifier chain (used by usbfs and possibly others).
2552          */
2553         err = device_add(&udev->dev);
2554         if (err) {
2555                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
2556                 goto fail;
2557         }
2558 
2559         /* Create link files between child device and usb port device. */
2560         if (udev->parent) {
2561                 struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2562                 int port1 = udev->portnum;
2563                 struct usb_port *port_dev = hub->ports[port1 - 1];
2564 
2565                 err = sysfs_create_link(&udev->dev.kobj,
2566                                 &port_dev->dev.kobj, "port");
2567                 if (err)
2568                         goto fail;
2569 
2570                 err = sysfs_create_link(&port_dev->dev.kobj,
2571                                 &udev->dev.kobj, "device");
2572                 if (err) {
2573                         sysfs_remove_link(&udev->dev.kobj, "port");
2574                         goto fail;
2575                 }
2576 
2577                 if (!test_and_set_bit(port1, hub->child_usage_bits))
2578                         pm_runtime_get_sync(&port_dev->dev);
2579         }
2580 
2581         (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2582         usb_mark_last_busy(udev);
2583         pm_runtime_put_sync_autosuspend(&udev->dev);
2584         return err;
2585 
2586 fail:
2587         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2588         pm_runtime_disable(&udev->dev);
2589         pm_runtime_set_suspended(&udev->dev);
2590         return err;
2591 }
2592 
2593 
2594 /**
2595  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2596  * @usb_dev: USB device
2597  *
2598  * Move the USB device to a very basic state where interfaces are disabled
2599  * and the device is in fact unconfigured and unusable.
2600  *
2601  * We share a lock (that we have) with device_del(), so we need to
2602  * defer its call.
2603  *
2604  * Return: 0.
2605  */
2606 int usb_deauthorize_device(struct usb_device *usb_dev)
2607 {
2608         usb_lock_device(usb_dev);
2609         if (usb_dev->authorized == 0)
2610                 goto out_unauthorized;
2611 
2612         usb_dev->authorized = 0;
2613         usb_set_configuration(usb_dev, -1);
2614 
2615 out_unauthorized:
2616         usb_unlock_device(usb_dev);
2617         return 0;
2618 }
2619 
2620 
2621 int usb_authorize_device(struct usb_device *usb_dev)
2622 {
2623         int result = 0, c;
2624 
2625         usb_lock_device(usb_dev);
2626         if (usb_dev->authorized == 1)
2627                 goto out_authorized;
2628 
2629         result = usb_autoresume_device(usb_dev);
2630         if (result < 0) {
2631                 dev_err(&usb_dev->dev,
2632                         "can't autoresume for authorization: %d\n", result);
2633                 goto error_autoresume;
2634         }
2635 
2636         if (usb_dev->wusb) {
2637                 result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2638                 if (result < 0) {
2639                         dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2640                                 "authorization: %d\n", result);
2641                         goto error_device_descriptor;
2642                 }
2643         }
2644 
2645         usb_dev->authorized = 1;
2646         /* Choose and set the configuration.  This registers the interfaces
2647          * with the driver core and lets interface drivers bind to them.
2648          */
2649         c = usb_choose_configuration(usb_dev);
2650         if (c >= 0) {
2651                 result = usb_set_configuration(usb_dev, c);
2652                 if (result) {
2653                         dev_err(&usb_dev->dev,
2654                                 "can't set config #%d, error %d\n", c, result);
2655                         /* This need not be fatal.  The user can try to
2656                          * set other configurations. */
2657                 }
2658         }
2659         dev_info(&usb_dev->dev, "authorized to connect\n");
2660 
2661 error_device_descriptor:
2662         usb_autosuspend_device(usb_dev);
2663 error_autoresume:
2664 out_authorized:
2665         usb_unlock_device(usb_dev);     /* complements locktree */
2666         return result;
2667 }
2668 
2669 /*
2670  * Return 1 if port speed is SuperSpeedPlus, 0 otherwise
2671  * check it from the link protocol field of the current speed ID attribute.
2672  * current speed ID is got from ext port status request. Sublink speed attribute
2673  * table is returned with the hub BOS SSP device capability descriptor
2674  */
2675 static int port_speed_is_ssp(struct usb_device *hdev, int speed_id)
2676 {
2677         int ssa_count;
2678         u32 ss_attr;
2679         int i;
2680         struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap;
2681 
2682         if (!ssp_cap)
2683                 return 0;
2684 
2685         ssa_count = le32_to_cpu(ssp_cap->bmAttributes) &
2686                 USB_SSP_SUBLINK_SPEED_ATTRIBS;
2687 
2688         for (i = 0; i <= ssa_count; i++) {
2689                 ss_attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2690                 if (speed_id == (ss_attr & USB_SSP_SUBLINK_SPEED_SSID))
2691                         return !!(ss_attr & USB_SSP_SUBLINK_SPEED_LP);
2692         }
2693         return 0;
2694 }
2695 
2696 /* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2697 static unsigned hub_is_wusb(struct usb_hub *hub)
2698 {
2699         struct usb_hcd *hcd;
2700         if (hub->hdev->parent != NULL)  /* not a root hub? */
2701                 return 0;
2702         hcd = bus_to_hcd(hub->hdev->bus);
2703         return hcd->wireless;
2704 }
2705 
2706 
2707 #define PORT_RESET_TRIES        5
2708 #define SET_ADDRESS_TRIES       2
2709 #define GET_DESCRIPTOR_TRIES    2
2710 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
2711 #define USE_NEW_SCHEME(i, scheme)       ((i) / 2 == (int)(scheme))
2712 
2713 #define HUB_ROOT_RESET_TIME     60      /* times are in msec */
2714 #define HUB_SHORT_RESET_TIME    10
2715 #define HUB_BH_RESET_TIME       50
2716 #define HUB_LONG_RESET_TIME     200
2717 #define HUB_RESET_TIMEOUT       800
2718 
2719 /*
2720  * "New scheme" enumeration causes an extra state transition to be
2721  * exposed to an xhci host and causes USB3 devices to receive control
2722  * commands in the default state.  This has been seen to cause
2723  * enumeration failures, so disable this enumeration scheme for USB3
2724  * devices.
2725  */
2726 static bool use_new_scheme(struct usb_device *udev, int retry,
2727                            struct usb_port *port_dev)
2728 {
2729         int old_scheme_first_port =
2730                 port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME;
2731 
2732         if (udev->speed >= USB_SPEED_SUPER)
2733                 return false;
2734 
2735         return USE_NEW_SCHEME(retry, old_scheme_first_port || old_scheme_first);
2736 }
2737 
2738 /* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2739  * Port warm reset is required to recover
2740  */
2741 static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2742                 u16 portstatus)
2743 {
2744         u16 link_state;
2745 
2746         if (!hub_is_superspeed(hub->hdev))
2747                 return false;
2748 
2749         if (test_bit(port1, hub->warm_reset_bits))
2750                 return true;
2751 
2752         link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2753         return link_state == USB_SS_PORT_LS_SS_INACTIVE
2754                 || link_state == USB_SS_PORT_LS_COMP_MOD;
2755 }
2756 
2757 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2758                         struct usb_device *udev, unsigned int delay, bool warm)
2759 {
2760         int delay_time, ret;
2761         u16 portstatus;
2762         u16 portchange;
2763         u32 ext_portstatus = 0;
2764 
2765         for (delay_time = 0;
2766                         delay_time < HUB_RESET_TIMEOUT;
2767                         delay_time += delay) {
2768                 /* wait to give the device a chance to reset */
2769                 msleep(delay);
2770 
2771                 /* read and decode port status */
2772                 if (hub_is_superspeedplus(hub->hdev))
2773                         ret = hub_ext_port_status(hub, port1,
2774                                                   HUB_EXT_PORT_STATUS,
2775                                                   &portstatus, &portchange,
2776                                                   &ext_portstatus);
2777                 else
2778                         ret = hub_port_status(hub, port1, &portstatus,
2779                                               &portchange);
2780                 if (ret < 0)
2781                         return ret;
2782 
2783                 /*
2784                  * The port state is unknown until the reset completes.
2785                  *
2786                  * On top of that, some chips may require additional time
2787                  * to re-establish a connection after the reset is complete,
2788                  * so also wait for the connection to be re-established.
2789                  */
2790                 if (!(portstatus & USB_PORT_STAT_RESET) &&
2791                     (portstatus & USB_PORT_STAT_CONNECTION))
2792                         break;
2793 
2794                 /* switch to the long delay after two short delay failures */
2795                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2796                         delay = HUB_LONG_RESET_TIME;
2797 
2798                 dev_dbg(&hub->ports[port1 - 1]->dev,
2799                                 "not %sreset yet, waiting %dms\n",
2800                                 warm ? "warm " : "", delay);
2801         }
2802 
2803         if ((portstatus & USB_PORT_STAT_RESET))
2804                 return -EBUSY;
2805 
2806         if (hub_port_warm_reset_required(hub, port1, portstatus))
2807                 return -ENOTCONN;
2808 
2809         /* Device went away? */
2810         if (!(portstatus & USB_PORT_STAT_CONNECTION))
2811                 return -ENOTCONN;
2812 
2813         /* Retry if connect change is set but status is still connected.
2814          * A USB 3.0 connection may bounce if multiple warm resets were issued,
2815          * but the device may have successfully re-connected. Ignore it.
2816          */
2817         if (!hub_is_superspeed(hub->hdev) &&
2818             (portchange & USB_PORT_STAT_C_CONNECTION)) {
2819                 usb_clear_port_feature(hub->hdev, port1,
2820                                        USB_PORT_FEAT_C_CONNECTION);
2821                 return -EAGAIN;
2822         }
2823 
2824         if (!(portstatus & USB_PORT_STAT_ENABLE))
2825                 return -EBUSY;
2826 
2827         if (!udev)
2828                 return 0;
2829 
2830         if (hub_is_superspeedplus(hub->hdev)) {
2831                 /* extended portstatus Rx and Tx lane count are zero based */
2832                 udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2833                 udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2834         } else {
2835                 udev->rx_lanes = 1;
2836                 udev->tx_lanes = 1;
2837         }
2838         if (hub_is_wusb(hub))
2839                 udev->speed = USB_SPEED_WIRELESS;
2840         else if (hub_is_superspeedplus(hub->hdev) &&
2841                  port_speed_is_ssp(hub->hdev, ext_portstatus &
2842                                    USB_EXT_PORT_STAT_RX_SPEED_ID))
2843                 udev->speed = USB_SPEED_SUPER_PLUS;
2844         else if (hub_is_superspeed(hub->hdev))
2845                 udev->speed = USB_SPEED_SUPER;
2846         else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2847                 udev->speed = USB_SPEED_HIGH;
2848         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2849                 udev->speed = USB_SPEED_LOW;
2850         else
2851                 udev->speed = USB_SPEED_FULL;
2852         return 0;
2853 }
2854 
2855 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2856 static int hub_port_reset(struct usb_hub *hub, int port1,
2857                         struct usb_device *udev, unsigned int delay, bool warm)
2858 {
2859         int i, status;
2860         u16 portchange, portstatus;
2861         struct usb_port *port_dev = hub->ports[port1 - 1];
2862         int reset_recovery_time;
2863 
2864         if (!hub_is_superspeed(hub->hdev)) {
2865                 if (warm) {
2866                         dev_err(hub->intfdev, "only USB3 hub support "
2867                                                 "warm reset\n");
2868                         return -EINVAL;
2869                 }
2870                 /* Block EHCI CF initialization during the port reset.
2871                  * Some companion controllers don't like it when they mix.
2872                  */
2873                 down_read(&ehci_cf_port_reset_rwsem);
2874         } else if (!warm) {
2875                 /*
2876                  * If the caller hasn't explicitly requested a warm reset,
2877                  * double check and see if one is needed.
2878                  */
2879                 if (hub_port_status(hub, port1, &portstatus, &portchange) == 0)
2880                         if (hub_port_warm_reset_required(hub, port1,
2881                                                         portstatus))
2882                                 warm = true;
2883         }
2884         clear_bit(port1, hub->warm_reset_bits);
2885 
2886         /* Reset the port */
2887         for (i = 0; i < PORT_RESET_TRIES; i++) {
2888                 status = set_port_feature(hub->hdev, port1, (warm ?
2889                                         USB_PORT_FEAT_BH_PORT_RESET :
2890                                         USB_PORT_FEAT_RESET));
2891                 if (status == -ENODEV) {
2892                         ;       /* The hub is gone */
2893                 } else if (status) {
2894                         dev_err(&port_dev->dev,
2895                                         "cannot %sreset (err = %d)\n",
2896                                         warm ? "warm " : "", status);
2897                 } else {
2898                         status = hub_port_wait_reset(hub, port1, udev, delay,
2899                                                                 warm);
2900                         if (status && status != -ENOTCONN && status != -ENODEV)
2901                                 dev_dbg(hub->intfdev,
2902                                                 "port_wait_reset: err = %d\n",
2903                                                 status);
2904                 }
2905 
2906                 /* Check for disconnect or reset */
2907                 if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2908                         usb_clear_port_feature(hub->hdev, port1,
2909                                         USB_PORT_FEAT_C_RESET);
2910 
2911                         if (!hub_is_superspeed(hub->hdev))
2912                                 goto done;
2913 
2914                         usb_clear_port_feature(hub->hdev, port1,
2915                                         USB_PORT_FEAT_C_BH_PORT_RESET);
2916                         usb_clear_port_feature(hub->hdev, port1,
2917                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
2918 
2919                         if (udev)
2920                                 usb_clear_port_feature(hub->hdev, port1,
2921                                         USB_PORT_FEAT_C_CONNECTION);
2922 
2923                         /*
2924                          * If a USB 3.0 device migrates from reset to an error
2925                          * state, re-issue the warm reset.
2926                          */
2927                         if (hub_port_status(hub, port1,
2928                                         &portstatus, &portchange) < 0)
2929                                 goto done;
2930 
2931                         if (!hub_port_warm_reset_required(hub, port1,
2932                                         portstatus))
2933                                 goto done;
2934 
2935                         /*
2936                          * If the port is in SS.Inactive or Compliance Mode, the
2937                          * hot or warm reset failed.  Try another warm reset.
2938                          */
2939                         if (!warm) {
2940                                 dev_dbg(&port_dev->dev,
2941                                                 "hot reset failed, warm reset\n");
2942                                 warm = true;
2943                         }
2944                 }
2945 
2946                 dev_dbg(&port_dev->dev,
2947                                 "not enabled, trying %sreset again...\n",
2948                                 warm ? "warm " : "");
2949                 delay = HUB_LONG_RESET_TIME;
2950         }
2951 
2952         dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
2953 
2954 done:
2955         if (status == 0) {
2956                 if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
2957                         usleep_range(10000, 12000);
2958                 else {
2959                         /* TRSTRCY = 10 ms; plus some extra */
2960                         reset_recovery_time = 10 + 40;
2961 
2962                         /* Hub needs extra delay after resetting its port. */
2963                         if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
2964                                 reset_recovery_time += 100;
2965 
2966                         msleep(reset_recovery_time);
2967                 }
2968 
2969                 if (udev) {
2970                         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2971 
2972                         update_devnum(udev, 0);
2973                         /* The xHC may think the device is already reset,
2974                          * so ignore the status.
2975                          */
2976                         if (hcd->driver->reset_device)
2977                                 hcd->driver->reset_device(hcd, udev);
2978 
2979                         usb_set_device_state(udev, USB_STATE_DEFAULT);
2980                 }
2981         } else {
2982                 if (udev)
2983                         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2984         }
2985 
2986         if (!hub_is_superspeed(hub->hdev))
2987                 up_read(&ehci_cf_port_reset_rwsem);
2988 
2989         return status;
2990 }
2991 
2992 /* Check if a port is power on */
2993 static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
2994 {
2995         int ret = 0;
2996 
2997         if (hub_is_superspeed(hub->hdev)) {
2998                 if (portstatus & USB_SS_PORT_STAT_POWER)
2999                         ret = 1;
3000         } else {
3001                 if (portstatus & USB_PORT_STAT_POWER)
3002                         ret = 1;
3003         }
3004 
3005         return ret;
3006 }
3007 
3008 static void usb_lock_port(struct usb_port *port_dev)
3009                 __acquires(&port_dev->status_lock)
3010 {
3011         mutex_lock(&port_dev->status_lock);
3012         __acquire(&port_dev->status_lock);
3013 }
3014 
3015 static void usb_unlock_port(struct usb_port *port_dev)
3016                 __releases(&port_dev->status_lock)
3017 {
3018         mutex_unlock(&port_dev->status_lock);
3019         __release(&port_dev->status_lock);
3020 }
3021 
3022 #ifdef  CONFIG_PM
3023 
3024 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
3025 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3026 {
3027         int ret = 0;
3028 
3029         if (hub_is_superspeed(hub->hdev)) {
3030                 if ((portstatus & USB_PORT_STAT_LINK_STATE)
3031                                 == USB_SS_PORT_LS_U3)
3032                         ret = 1;
3033         } else {
3034                 if (portstatus & USB_PORT_STAT_SUSPEND)
3035                         ret = 1;
3036         }
3037 
3038         return ret;
3039 }
3040 
3041 /* Determine whether the device on a port is ready for a normal resume,
3042  * is ready for a reset-resume, or should be disconnected.
3043  */
3044 static int check_port_resume_type(struct usb_device *udev,
3045                 struct usb_hub *hub, int port1,
3046                 int status, u16 portchange, u16 portstatus)
3047 {
3048         struct usb_port *port_dev = hub->ports[port1 - 1];
3049         int retries = 3;
3050 
3051  retry:
3052         /* Is a warm reset needed to recover the connection? */
3053         if (status == 0 && udev->reset_resume
3054                 && hub_port_warm_reset_required(hub, port1, portstatus)) {
3055                 /* pass */;
3056         }
3057         /* Is the device still present? */
3058         else if (status || port_is_suspended(hub, portstatus) ||
3059                         !port_is_power_on(hub, portstatus)) {
3060                 if (status >= 0)
3061                         status = -ENODEV;
3062         } else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3063                 if (retries--) {
3064                         usleep_range(200, 300);
3065                         status = hub_port_status(hub, port1, &portstatus,
3066                                                              &portchange);
3067                         goto retry;
3068                 }
3069                 status = -ENODEV;
3070         }
3071 
3072         /* Can't do a normal resume if the port isn't enabled,
3073          * so try a reset-resume instead.
3074          */
3075         else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3076                 if (udev->persist_enabled)
3077                         udev->reset_resume = 1;
3078                 else
3079                         status = -ENODEV;
3080         }
3081 
3082         if (status) {
3083                 dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3084                                 portchange, portstatus, status);
3085         } else if (udev->reset_resume) {
3086 
3087                 /* Late port handoff can set status-change bits */
3088                 if (portchange & USB_PORT_STAT_C_CONNECTION)
3089                         usb_clear_port_feature(hub->hdev, port1,
3090                                         USB_PORT_FEAT_C_CONNECTION);
3091                 if (portchange & USB_PORT_STAT_C_ENABLE)
3092                         usb_clear_port_feature(hub->hdev, port1,
3093                                         USB_PORT_FEAT_C_ENABLE);
3094 
3095                 /*
3096                  * Whatever made this reset-resume necessary may have
3097                  * turned on the port1 bit in hub->change_bits.  But after
3098                  * a successful reset-resume we want the bit to be clear;
3099                  * if it was on it would indicate that something happened
3100                  * following the reset-resume.
3101                  */
3102                 clear_bit(port1, hub->change_bits);
3103         }
3104 
3105         return status;
3106 }
3107 
3108 int usb_disable_ltm(struct usb_device *udev)
3109 {
3110         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3111 
3112         /* Check if the roothub and device supports LTM. */
3113         if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3114                         !usb_device_supports_ltm(udev))
3115                 return 0;
3116 
3117         /* Clear Feature LTM Enable can only be sent if the device is
3118          * configured.
3119          */
3120         if (!udev->actconfig)
3121                 return 0;
3122 
3123         return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3124                         USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3125                         USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3126                         USB_CTRL_SET_TIMEOUT);
3127 }
3128 EXPORT_SYMBOL_GPL(usb_disable_ltm);
3129 
3130 void usb_enable_ltm(struct usb_device *udev)
3131 {
3132         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3133 
3134         /* Check if the roothub and device supports LTM. */
3135         if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3136                         !usb_device_supports_ltm(udev))
3137                 return;
3138 
3139         /* Set Feature LTM Enable can only be sent if the device is
3140          * configured.
3141          */
3142         if (!udev->actconfig)
3143                 return;
3144 
3145         usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3146                         USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3147                         USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3148                         USB_CTRL_SET_TIMEOUT);
3149 }
3150 EXPORT_SYMBOL_GPL(usb_enable_ltm);
3151 
3152 /*
3153  * usb_enable_remote_wakeup - enable remote wakeup for a device
3154  * @udev: target device
3155  *
3156  * For USB-2 devices: Set the device's remote wakeup feature.
3157  *
3158  * For USB-3 devices: Assume there's only one function on the device and
3159  * enable remote wake for the first interface.  FIXME if the interface
3160  * association descriptor shows there's more than one function.
3161  */
3162 static int usb_enable_remote_wakeup(struct usb_device *udev)
3163 {
3164         if (udev->speed < USB_SPEED_SUPER)
3165                 return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3166                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3167                                 USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3168                                 USB_CTRL_SET_TIMEOUT);
3169         else
3170                 return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3171                                 USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3172                                 USB_INTRF_FUNC_SUSPEND,
3173                                 USB_INTRF_FUNC_SUSPEND_RW |
3174                                         USB_INTRF_FUNC_SUSPEND_LP,
3175                                 NULL, 0, USB_CTRL_SET_TIMEOUT);
3176 }
3177 
3178 /*
3179  * usb_disable_remote_wakeup - disable remote wakeup for a device
3180  * @udev: target device
3181  *
3182  * For USB-2 devices: Clear the device's remote wakeup feature.
3183  *
3184  * For USB-3 devices: Assume there's only one function on the device and
3185  * disable remote wake for the first interface.  FIXME if the interface
3186  * association descriptor shows there's more than one function.
3187  */
3188 static int usb_disable_remote_wakeup(struct usb_device *udev)
3189 {
3190         if (udev->speed < USB_SPEED_SUPER)
3191                 return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3192                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3193                                 USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3194                                 USB_CTRL_SET_TIMEOUT);
3195         else
3196                 return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3197                                 USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3198                                 USB_INTRF_FUNC_SUSPEND, 0, NULL, 0,
3199                                 USB_CTRL_SET_TIMEOUT);
3200 }
3201 
3202 /* Count of wakeup-enabled devices at or below udev */
3203 unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3204 {
3205         struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3206 
3207         return udev->do_remote_wakeup +
3208                         (hub ? hub->wakeup_enabled_descendants : 0);
3209 }
3210 EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3211 
3212 /*
3213  * usb_port_suspend - suspend a usb device's upstream port
3214  * @udev: device that's no longer in active use, not a root hub
3215  * Context: must be able to sleep; device not locked; pm locks held
3216  *
3217  * Suspends a USB device that isn't in active use, conserving power.
3218  * Devices may wake out of a suspend, if anything important happens,
3219  * using the remote wakeup mechanism.  They may also be taken out of
3220  * suspend by the host, using usb_port_resume().  It's also routine
3221  * to disconnect devices while they are suspended.
3222  *
3223  * This only affects the USB hardware for a device; its interfaces
3224  * (and, for hubs, child devices) must already have been suspended.
3225  *
3226  * Selective port suspend reduces power; most suspended devices draw
3227  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3228  * All devices below the suspended port are also suspended.
3229  *
3230  * Devices leave suspend state when the host wakes them up.  Some devices
3231  * also support "remote wakeup", where the device can activate the USB
3232  * tree above them to deliver data, such as a keypress or packet.  In
3233  * some cases, this wakes the USB host.
3234  *
3235  * Suspending OTG devices may trigger HNP, if that's been enabled
3236  * between a pair of dual-role devices.  That will change roles, such
3237  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3238  *
3239  * Devices on USB hub ports have only one "suspend" state, corresponding
3240  * to ACPI D2, "may cause the device to lose some context".
3241  * State transitions include:
3242  *
3243  *   - suspend, resume ... when the VBUS power link stays live
3244  *   - suspend, disconnect ... VBUS lost
3245  *
3246  * Once VBUS drop breaks the circuit, the port it's using has to go through
3247  * normal re-enumeration procedures, starting with enabling VBUS power.
3248  * Other than re-initializing the hub (plug/unplug, except for root hubs),
3249  * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3250  * timer, no SRP, no requests through sysfs.
3251  *
3252  * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3253  * suspended until their bus goes into global suspend (i.e., the root
3254  * hub is suspended).  Nevertheless, we change @udev->state to
3255  * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3256  * upstream port setting is stored in @udev->port_is_suspended.
3257  *
3258  * Returns 0 on success, else negative errno.
3259  */
3260 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3261 {
3262         struct usb_hub  *hub = usb_hub_to_struct_hub(udev->parent);
3263         struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3264         int             port1 = udev->portnum;
3265         int             status;
3266         bool            really_suspend = true;
3267 
3268         usb_lock_port(port_dev);
3269 
3270         /* enable remote wakeup when appropriate; this lets the device
3271          * wake up the upstream hub (including maybe the root hub).
3272          *
3273          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3274          * we don't explicitly enable it here.
3275          */
3276         if (udev->do_remote_wakeup) {
3277                 status = usb_enable_remote_wakeup(udev);
3278                 if (status) {
3279                         dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3280                                         status);
3281                         /* bail if autosuspend is requested */
3282                         if (PMSG_IS_AUTO(msg))
3283                                 goto err_wakeup;
3284                 }
3285         }
3286 
3287         /* disable USB2 hardware LPM */
3288         usb_disable_usb2_hardware_lpm(udev);
3289 
3290         if (usb_disable_ltm(udev)) {
3291                 dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3292                 status = -ENOMEM;
3293                 if (PMSG_IS_AUTO(msg))
3294                         goto err_ltm;
3295         }
3296 
3297         /* see 7.1.7.6 */
3298         if (hub_is_superspeed(hub->hdev))
3299                 status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3300 
3301         /*
3302          * For system suspend, we do not need to enable the suspend feature
3303          * on individual USB-2 ports.  The devices will automatically go
3304          * into suspend a few ms after the root hub stops sending packets.
3305          * The USB 2.0 spec calls this "global suspend".
3306          *
3307          * However, many USB hubs have a bug: They don't relay wakeup requests
3308          * from a downstream port if the port's suspend feature isn't on.
3309          * Therefore we will turn on the suspend feature if udev or any of its
3310          * descendants is enabled for remote wakeup.
3311          */
3312         else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3313                 status = set_port_feature(hub->hdev, port1,
3314                                 USB_PORT_FEAT_SUSPEND);
3315         else {
3316                 really_suspend = false;
3317                 status = 0;
3318         }
3319         if (status) {
3320                 dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3321 
3322                 /* Try to enable USB3 LTM again */
3323                 usb_enable_ltm(udev);
3324  err_ltm:
3325                 /* Try to enable USB2 hardware LPM again */
3326                 usb_enable_usb2_hardware_lpm(udev);
3327 
3328                 if (udev->do_remote_wakeup)
3329                         (void) usb_disable_remote_wakeup(udev);
3330  err_wakeup:
3331 
3332                 /* System sleep transitions should never fail */
3333                 if (!PMSG_IS_AUTO(msg))
3334                         status = 0;
3335         } else {
3336                 dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3337                                 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
3338                                 udev->do_remote_wakeup);
3339                 if (really_suspend) {
3340                         udev->port_is_suspended = 1;
3341 
3342                         /* device has up to 10 msec to fully suspend */
3343                         msleep(10);
3344                 }
3345                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
3346         }
3347 
3348         if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3349                         && test_and_clear_bit(port1, hub->child_usage_bits))
3350                 pm_runtime_put_sync(&port_dev->dev);
3351 
3352         usb_mark_last_busy(hub->hdev);
3353 
3354         usb_unlock_port(port_dev);
3355         return status;
3356 }
3357 
3358 /*
3359  * If the USB "suspend" state is in use (rather than "global suspend"),
3360  * many devices will be individually taken out of suspend state using
3361  * special "resume" signaling.  This routine kicks in shortly after
3362  * hardware resume signaling is finished, either because of selective
3363  * resume (by host) or remote wakeup (by device) ... now see what changed
3364  * in the tree that's rooted at this device.
3365  *
3366  * If @udev->reset_resume is set then the device is reset before the
3367  * status check is done.
3368  */
3369 static int finish_port_resume(struct usb_device *udev)
3370 {
3371         int     status = 0;
3372         u16     devstatus = 0;
3373 
3374         /* caller owns the udev device lock */
3375         dev_dbg(&udev->dev, "%s\n",
3376                 udev->reset_resume ? "finish reset-resume" : "finish resume");
3377 
3378         /* usb ch9 identifies four variants of SUSPENDED, based on what
3379          * state the device resumes to.  Linux currently won't see the
3380          * first two on the host side; they'd be inside hub_port_init()
3381          * during many timeouts, but hub_wq can't suspend until later.
3382          */
3383         usb_set_device_state(udev, udev->actconfig
3384                         ? USB_STATE_CONFIGURED
3385                         : USB_STATE_ADDRESS);
3386 
3387         /* 10.5.4.5 says not to reset a suspended port if the attached
3388          * device is enabled for remote wakeup.  Hence the reset
3389          * operation is carried out here, after the port has been
3390          * resumed.
3391          */
3392         if (udev->reset_resume) {
3393                 /*
3394                  * If the device morphs or switches modes when it is reset,
3395                  * we don't want to perform a reset-resume.  We'll fail the
3396                  * resume, which will cause a logical disconnect, and then
3397                  * the device will be rediscovered.
3398                  */
3399  retry_reset_resume:
3400                 if (udev->quirks & USB_QUIRK_RESET)
3401                         status = -ENODEV;
3402                 else
3403                         status = usb_reset_and_verify_device(udev);
3404         }
3405 
3406         /* 10.5.4.5 says be sure devices in the tree are still there.
3407          * For now let's assume the device didn't go crazy on resume,
3408          * and device drivers will know about any resume quirks.
3409          */
3410         if (status == 0) {
3411                 devstatus = 0;
3412                 status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3413 
3414                 /* If a normal resume failed, try doing a reset-resume */
3415                 if (status && !udev->reset_resume && udev->persist_enabled) {
3416                         dev_dbg(&udev->dev, "retry with reset-resume\n");
3417                         udev->reset_resume = 1;
3418                         goto retry_reset_resume;
3419                 }
3420         }
3421 
3422         if (status) {
3423                 dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3424                                 status);
3425         /*
3426          * There are a few quirky devices which violate the standard
3427          * by claiming to have remote wakeup enabled after a reset,
3428          * which crash if the feature is cleared, hence check for
3429          * udev->reset_resume
3430          */
3431         } else if (udev->actconfig && !udev->reset_resume) {
3432                 if (udev->speed < USB_SPEED_SUPER) {
3433                         if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3434                                 status = usb_disable_remote_wakeup(udev);
3435                 } else {
3436                         status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3437                                         &devstatus);
3438                         if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3439                                         | USB_INTRF_STAT_FUNC_RW))
3440                                 status = usb_disable_remote_wakeup(udev);
3441                 }
3442 
3443                 if (status)
3444                         dev_dbg(&udev->dev,
3445                                 "disable remote wakeup, status %d\n",
3446                                 status);
3447                 status = 0;
3448         }
3449         return status;
3450 }
3451 
3452 /*
3453  * There are some SS USB devices which take longer time for link training.
3454  * XHCI specs 4.19.4 says that when Link training is successful, port
3455  * sets CCS bit to 1. So if SW reads port status before successful link
3456  * training, then it will not find device to be present.
3457  * USB Analyzer log with such buggy devices show that in some cases
3458  * device switch on the RX termination after long delay of host enabling
3459  * the VBUS. In few other cases it has been seen that device fails to
3460  * negotiate link training in first attempt. It has been
3461  * reported till now that few devices take as long as 2000 ms to train
3462  * the link after host enabling its VBUS and termination. Following
3463  * routine implements a 2000 ms timeout for link training. If in a case
3464  * link trains before timeout, loop will exit earlier.
3465  *
3466  * There are also some 2.0 hard drive based devices and 3.0 thumb
3467  * drives that, when plugged into a 2.0 only port, take a long
3468  * time to set CCS after VBUS enable.
3469  *
3470  * FIXME: If a device was connected before suspend, but was removed
3471  * while system was asleep, then the loop in the following routine will
3472  * only exit at timeout.
3473  *
3474  * This routine should only be called when persist is enabled.
3475  */
3476 static int wait_for_connected(struct usb_device *udev,
3477                 struct usb_hub *hub, int *port1,
3478                 u16 *portchange, u16 *portstatus)
3479 {
3480         int status = 0, delay_ms = 0;
3481 
3482         while (delay_ms < 2000) {
3483                 if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3484                         break;
3485                 if (!port_is_power_on(hub, *portstatus)) {
3486                         status = -ENODEV;
3487                         break;
3488                 }
3489                 msleep(20);
3490                 delay_ms += 20;
3491                 status = hub_port_status(hub, *port1, portstatus, portchange);
3492         }
3493         dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3494         return status;
3495 }
3496 
3497 /*
3498  * usb_port_resume - re-activate a suspended usb device's upstream port
3499  * @udev: device to re-activate, not a root hub
3500  * Context: must be able to sleep; device not locked; pm locks held
3501  *
3502  * This will re-activate the suspended device, increasing power usage
3503  * while letting drivers communicate again with its endpoints.
3504  * USB resume explicitly guarantees that the power session between
3505  * the host and the device is the same as it was when the device
3506  * suspended.
3507  *
3508  * If @udev->reset_resume is set then this routine won't check that the
3509  * port is still enabled.  Furthermore, finish_port_resume() above will
3510  * reset @udev.  The end result is that a broken power session can be
3511  * recovered and @udev will appear to persist across a loss of VBUS power.
3512  *
3513  * For example, if a host controller doesn't maintain VBUS suspend current
3514  * during a system sleep or is reset when the system wakes up, all the USB
3515  * power sessions below it will be broken.  This is especially troublesome
3516  * for mass-storage devices containing mounted filesystems, since the
3517  * device will appear to have disconnected and all the memory mappings
3518  * to it will be lost.  Using the USB_PERSIST facility, the device can be
3519  * made to appear as if it had not disconnected.
3520  *
3521  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3522  * every effort to insure that the same device is present after the
3523  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3524  * quite possible for a device to remain unaltered but its media to be
3525  * changed.  If the user replaces a flash memory card while the system is
3526  * asleep, he will have only himself to blame when the filesystem on the
3527  * new card is corrupted and the system crashes.
3528  *
3529  * Returns 0 on success, else negative errno.
3530  */
3531 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3532 {
3533         struct usb_hub  *hub = usb_hub_to_struct_hub(udev->parent);
3534         struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3535         int             port1 = udev->portnum;
3536         int             status;
3537         u16             portchange, portstatus;
3538 
3539         if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3540                 status = pm_runtime_get_sync(&port_dev->dev);
3541                 if (status < 0) {
3542                         dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3543                                         status);
3544                         return status;
3545                 }
3546         }
3547 
3548         usb_lock_port(port_dev);
3549 
3550         /* Skip the initial Clear-Suspend step for a remote wakeup */
3551         status = hub_port_status(hub, port1, &portstatus, &portchange);
3552         if (status == 0 && !port_is_suspended(hub, portstatus)) {
3553                 if (portchange & USB_PORT_STAT_C_SUSPEND)
3554                         pm_wakeup_event(&udev->dev, 0);
3555                 goto SuspendCleared;
3556         }
3557 
3558         /* see 7.1.7.7; affects power usage, but not budgeting */
3559         if (hub_is_superspeed(hub->hdev))
3560                 status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3561         else
3562                 status = usb_clear_port_feature(hub->hdev,
3563                                 port1, USB_PORT_FEAT_SUSPEND);
3564         if (status) {
3565                 dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3566         } else {
3567                 /* drive resume for USB_RESUME_TIMEOUT msec */
3568                 dev_dbg(&udev->dev, "usb %sresume\n",
3569                                 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
3570                 msleep(USB_RESUME_TIMEOUT);
3571 
3572                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
3573                  * stop resume signaling.  Then finish the resume
3574                  * sequence.
3575                  */
3576                 status = hub_port_status(hub, port1, &portstatus, &portchange);
3577 
3578                 /* TRSMRCY = 10 msec */
3579                 msleep(10);
3580         }
3581 
3582  SuspendCleared:
3583         if (status == 0) {
3584                 udev->port_is_suspended = 0;
3585                 if (hub_is_superspeed(hub->hdev)) {
3586                         if (portchange & USB_PORT_STAT_C_LINK_STATE)
3587                                 usb_clear_port_feature(hub->hdev, port1,
3588                                         USB_PORT_FEAT_C_PORT_LINK_STATE);
3589                 } else {
3590                         if (portchange & USB_PORT_STAT_C_SUSPEND)
3591                                 usb_clear_port_feature(hub->hdev, port1,
3592                                                 USB_PORT_FEAT_C_SUSPEND);
3593                 }
3594         }
3595 
3596         if (udev->persist_enabled)
3597                 status = wait_for_connected(udev, hub, &port1, &portchange,
3598                                 &portstatus);
3599 
3600         status = check_port_resume_type(udev,
3601                         hub, port1, status, portchange, portstatus);
3602         if (status == 0)
3603                 status = finish_port_resume(udev);
3604         if (status < 0) {
3605                 dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3606                 hub_port_logical_disconnect(hub, port1);
3607         } else  {
3608                 /* Try to enable USB2 hardware LPM */
3609                 usb_enable_usb2_hardware_lpm(udev);
3610 
3611                 /* Try to enable USB3 LTM */
3612                 usb_enable_ltm(udev);
3613         }
3614 
3615         usb_unlock_port(port_dev);
3616 
3617         return status;
3618 }
3619 
3620 int usb_remote_wakeup(struct usb_device *udev)
3621 {
3622         int     status = 0;
3623 
3624         usb_lock_device(udev);
3625         if (udev->state == USB_STATE_SUSPENDED) {
3626                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3627                 status = usb_autoresume_device(udev);
3628                 if (status == 0) {
3629                         /* Let the drivers do their thing, then... */
3630                         usb_autosuspend_device(udev);
3631                 }
3632         }
3633         usb_unlock_device(udev);
3634         return status;
3635 }
3636 
3637 /* Returns 1 if there was a remote wakeup and a connect status change. */
3638 static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3639                 u16 portstatus, u16 portchange)
3640                 __must_hold(&port_dev->status_lock)
3641 {
3642         struct usb_port *port_dev = hub->ports[port - 1];
3643         struct usb_device *hdev;
3644         struct usb_device *udev;
3645         int connect_change = 0;
3646         u16 link_state;
3647         int ret;
3648 
3649         hdev = hub->hdev;
3650         udev = port_dev->child;
3651         if (!hub_is_superspeed(hdev)) {
3652                 if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3653                         return 0;
3654                 usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3655         } else {
3656                 link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3657                 if (!udev || udev->state != USB_STATE_SUSPENDED ||
3658                                 (link_state != USB_SS_PORT_LS_U0 &&
3659                                  link_state != USB_SS_PORT_LS_U1 &&
3660                                  link_state != USB_SS_PORT_LS_U2))
3661                         return 0;
3662         }
3663 
3664         if (udev) {
3665                 /* TRSMRCY = 10 msec */
3666                 msleep(10);
3667 
3668                 usb_unlock_port(port_dev);
3669                 ret = usb_remote_wakeup(udev);
3670                 usb_lock_port(port_dev);
3671                 if (ret < 0)
3672                         connect_change = 1;
3673         } else {
3674                 ret = -ENODEV;
3675                 hub_port_disable(hub, port, 1);
3676         }
3677         dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3678         return connect_change;
3679 }
3680 
3681 static int check_ports_changed(struct usb_hub *hub)
3682 {
3683         int port1;
3684 
3685         for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3686                 u16 portstatus, portchange;
3687                 int status;
3688 
3689                 status = hub_port_status(hub, port1, &portstatus, &portchange);
3690                 if (!status && portchange)
3691                         return 1;
3692         }
3693         return 0;
3694 }
3695 
3696 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3697 {
3698         struct usb_hub          *hub = usb_get_intfdata(intf);
3699         struct usb_device       *hdev = hub->hdev;
3700         unsigned                port1;
3701 
3702         /*
3703          * Warn if children aren't already suspended.
3704          * Also, add up the number of wakeup-enabled descendants.
3705          */
3706         hub->wakeup_enabled_descendants = 0;
3707         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3708                 struct usb_port *port_dev = hub->ports[port1 - 1];
3709                 struct usb_device *udev = port_dev->child;
3710 
3711                 if (udev && udev->can_submit) {
3712                         dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3713                                         dev_name(&udev->dev));
3714                         if (PMSG_IS_AUTO(msg))
3715                                 return -EBUSY;
3716                 }
3717                 if (udev)
3718                         hub->wakeup_enabled_descendants +=
3719                                         usb_wakeup_enabled_descendants(udev);
3720         }
3721 
3722         if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3723                 /* check if there are changes pending on hub ports */
3724                 if (check_ports_changed(hub)) {
3725                         if (PMSG_IS_AUTO(msg))
3726                                 return -EBUSY;
3727                         pm_wakeup_event(&hdev->dev, 2000);
3728                 }
3729         }
3730 
3731         if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3732                 /* Enable hub to send remote wakeup for all ports. */
3733                 for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3734                         set_port_feature(hdev,
3735                                          port1 |
3736                                          USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3737                                          USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3738                                          USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3739                                          USB_PORT_FEAT_REMOTE_WAKE_MASK);
3740                 }
3741         }
3742 
3743         dev_dbg(&intf->dev, "%s\n", __func__);
3744 
3745         /* stop hub_wq and related activity */
3746         hub_quiesce(hub, HUB_SUSPEND);
3747         return 0;
3748 }
3749 
3750 /* Report wakeup requests from the ports of a resuming root hub */
3751 static void report_wakeup_requests(struct usb_hub *hub)
3752 {
3753         struct usb_device       *hdev = hub->hdev;
3754         struct usb_device       *udev;
3755         struct usb_hcd          *hcd;
3756         unsigned long           resuming_ports;
3757         int                     i;
3758 
3759         if (hdev->parent)
3760                 return;         /* Not a root hub */
3761 
3762         hcd = bus_to_hcd(hdev->bus);
3763         if (hcd->driver->get_resuming_ports) {
3764 
3765                 /*
3766                  * The get_resuming_ports() method returns a bitmap (origin 0)
3767                  * of ports which have started wakeup signaling but have not
3768                  * yet finished resuming.  During system resume we will
3769                  * resume all the enabled ports, regardless of any wakeup
3770                  * signals, which means the wakeup requests would be lost.
3771                  * To prevent this, report them to the PM core here.
3772                  */
3773                 resuming_ports = hcd->driver->get_resuming_ports(hcd);
3774                 for (i = 0; i < hdev->maxchild; ++i) {
3775                         if (test_bit(i, &resuming_ports)) {
3776                                 udev = hub->ports[i]->child;
3777                                 if (udev)
3778                                         pm_wakeup_event(&udev->dev, 0);
3779                         }
3780                 }
3781         }
3782 }
3783 
3784 static int hub_resume(struct usb_interface *intf)
3785 {
3786         struct usb_hub *hub = usb_get_intfdata(intf);
3787 
3788         dev_dbg(&intf->dev, "%s\n", __func__);
3789         hub_activate(hub, HUB_RESUME);
3790 
3791         /*
3792          * This should be called only for system resume, not runtime resume.
3793          * We can't tell the difference here, so some wakeup requests will be
3794          * reported at the wrong time or more than once.  This shouldn't
3795          * matter much, so long as they do get reported.
3796          */
3797         report_wakeup_requests(hub);
3798         return 0;
3799 }
3800 
3801 static int hub_reset_resume(struct usb_interface *intf)
3802 {
3803         struct usb_hub *hub = usb_get_intfdata(intf);
3804 
3805         dev_dbg(&intf->dev, "%s\n", __func__);
3806         hub_activate(hub, HUB_RESET_RESUME);
3807         return 0;
3808 }
3809 
3810 /**
3811  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3812  * @rhdev: struct usb_device for the root hub
3813  *
3814  * The USB host controller driver calls this function when its root hub
3815  * is resumed and Vbus power has been interrupted or the controller
3816  * has been reset.  The routine marks @rhdev as having lost power.
3817  * When the hub driver is resumed it will take notice and carry out
3818  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3819  * the others will be disconnected.
3820  */
3821 void usb_root_hub_lost_power(struct usb_device *rhdev)
3822 {
3823         dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
3824         rhdev->reset_resume = 1;
3825 }
3826 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3827 
3828 static const char * const usb3_lpm_names[]  = {
3829         "U0",
3830         "U1",
3831         "U2",
3832         "U3",
3833 };
3834 
3835 /*
3836  * Send a Set SEL control transfer to the device, prior to enabling
3837  * device-initiated U1 or U2.  This lets the device know the exit latencies from
3838  * the time the device initiates a U1 or U2 exit, to the time it will receive a
3839  * packet from the host.
3840  *
3841  * This function will fail if the SEL or PEL values for udev are greater than
3842  * the maximum allowed values for the link state to be enabled.
3843  */
3844 static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
3845 {
3846         struct usb_set_sel_req *sel_values;
3847         unsigned long long u1_sel;
3848         unsigned long long u1_pel;
3849         unsigned long long u2_sel;
3850         unsigned long long u2_pel;
3851         int ret;
3852 
3853         if (udev->state != USB_STATE_CONFIGURED)
3854                 return 0;
3855 
3856         /* Convert SEL and PEL stored in ns to us */
3857         u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
3858         u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
3859         u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
3860         u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
3861 
3862         /*
3863          * Make sure that the calculated SEL and PEL values for the link
3864          * state we're enabling aren't bigger than the max SEL/PEL
3865          * value that will fit in the SET SEL control transfer.
3866          * Otherwise the device would get an incorrect idea of the exit
3867          * latency for the link state, and could start a device-initiated
3868          * U1/U2 when the exit latencies are too high.
3869          */
3870         if ((state == USB3_LPM_U1 &&
3871                                 (u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
3872                                  u1_pel > USB3_LPM_MAX_U1_SEL_PEL)) ||
3873                         (state == USB3_LPM_U2 &&
3874                          (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
3875                           u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
3876                 dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n",
3877                                 usb3_lpm_names[state], u1_sel, u1_pel);
3878                 return -EINVAL;
3879         }
3880 
3881         /*
3882          * If we're enabling device-initiated LPM for one link state,
3883          * but the other link state has a too high SEL or PEL value,
3884          * just set those values to the max in the Set SEL request.
3885          */
3886         if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL)
3887                 u1_sel = USB3_LPM_MAX_U1_SEL_PEL;
3888 
3889         if (u1_pel > USB3_LPM_MAX_U1_SEL_PEL)
3890                 u1_pel = USB3_LPM_MAX_U1_SEL_PEL;
3891 
3892         if (u2_sel > USB3_LPM_MAX_U2_SEL_PEL)
3893                 u2_sel = USB3_LPM_MAX_U2_SEL_PEL;
3894 
3895         if (u2_pel > USB3_LPM_MAX_U2_SEL_PEL)
3896                 u2_pel = USB3_LPM_MAX_U2_SEL_PEL;
3897 
3898         /*
3899          * usb_enable_lpm() can be called as part of a failed device reset,
3900          * which may be initiated by an error path of a mass storage driver.
3901          * Therefore, use GFP_NOIO.
3902          */
3903         sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
3904         if (!sel_values)
3905                 return -ENOMEM;
3906 
3907         sel_values->u1_sel = u1_sel;
3908         sel_values->u1_pel = u1_pel;
3909         sel_values->u2_sel = cpu_to_le16(u2_sel);
3910         sel_values->u2_pel = cpu_to_le16(u2_pel);
3911 
3912         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3913                         USB_REQ_SET_SEL,
3914                         USB_RECIP_DEVICE,
3915                         0, 0,
3916                         sel_values, sizeof *(sel_values),
3917                         USB_CTRL_SET_TIMEOUT);
3918         kfree(sel_values);
3919         return ret;
3920 }
3921 
3922 /*
3923  * Enable or disable device-initiated U1 or U2 transitions.
3924  */
3925 static int usb_set_device_initiated_lpm(struct usb_device *udev,
3926                 enum usb3_link_state state, bool enable)
3927 {
3928         int ret;
3929         int feature;
3930 
3931         switch (state) {
3932         case USB3_LPM_U1:
3933                 feature = USB_DEVICE_U1_ENABLE;
3934                 break;
3935         case USB3_LPM_U2:
3936                 feature = USB_DEVICE_U2_ENABLE;
3937                 break;
3938         default:
3939                 dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
3940                                 __func__, enable ? "enable" : "disable");
3941                 return -EINVAL;
3942         }
3943 
3944         if (udev->state != USB_STATE_CONFIGURED) {
3945                 dev_dbg(&udev->dev, "%s: Can't %s %s state "
3946                                 "for unconfigured device.\n",
3947                                 __func__, enable ? "enable" : "disable",
3948                                 usb3_lpm_names[state]);
3949                 return 0;
3950         }
3951 
3952         if (enable) {
3953                 /*
3954                  * Now send the control transfer to enable device-initiated LPM
3955                  * for either U1 or U2.
3956                  */
3957                 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3958                                 USB_REQ_SET_FEATURE,
3959                                 USB_RECIP_DEVICE,
3960                                 feature,
3961                                 0, NULL, 0,
3962                                 USB_CTRL_SET_TIMEOUT);
3963         } else {
3964                 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3965                                 USB_REQ_CLEAR_FEATURE,
3966                                 USB_RECIP_DEVICE,
3967                                 feature,
3968                                 0, NULL, 0,
3969                                 USB_CTRL_SET_TIMEOUT);
3970         }
3971         if (ret < 0) {
3972                 dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
3973                                 enable ? "Enable" : "Disable",
3974                                 usb3_lpm_names[state]);
3975                 return -EBUSY;
3976         }
3977         return 0;
3978 }
3979 
3980 static int usb_set_lpm_timeout(struct usb_device *udev,
3981                 enum usb3_link_state state, int timeout)
3982 {
3983         int ret;
3984         int feature;
3985 
3986         switch (state) {
3987         case USB3_LPM_U1:
3988                 feature = USB_PORT_FEAT_U1_TIMEOUT;
3989                 break;
3990         case USB3_LPM_U2:
3991                 feature = USB_PORT_FEAT_U2_TIMEOUT;
3992                 break;
3993         default:
3994                 dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
3995                                 __func__);
3996                 return -EINVAL;
3997         }
3998 
3999         if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
4000                         timeout != USB3_LPM_DEVICE_INITIATED) {
4001                 dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
4002                                 "which is a reserved value.\n",
4003                                 usb3_lpm_names[state], timeout);
4004                 return -EINVAL;
4005         }
4006 
4007         ret = set_port_feature(udev->parent,
4008                         USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
4009                         feature);
4010         if (ret < 0) {
4011                 dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
4012                                 "error code %i\n", usb3_lpm_names[state],
4013                                 timeout, ret);
4014                 return -EBUSY;
4015         }
4016         if (state == USB3_LPM_U1)
4017                 udev->u1_params.timeout = timeout;
4018         else
4019                 udev->u2_params.timeout = timeout;
4020         return 0;
4021 }
4022 
4023 /*
4024  * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4025  * U1/U2 entry.
4026  *
4027  * We will attempt to enable U1 or U2, but there are no guarantees that the
4028  * control transfers to set the hub timeout or enable device-initiated U1/U2
4029  * will be successful.
4030  *
4031  * If the control transfer to enable device-initiated U1/U2 entry fails, then
4032  * hub-initiated U1/U2 will be disabled.
4033  *
4034  * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4035  * driver know about it.  If that call fails, it should be harmless, and just
4036  * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4037  */
4038 static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4039                 enum usb3_link_state state)
4040 {
4041         int timeout, ret;
4042         __u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
4043         __le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4044 
4045         /* If the device says it doesn't have *any* exit latency to come out of
4046          * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4047          * state.
4048          */
4049         if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4050                         (state == USB3_LPM_U2 && u2_mel == 0))
4051                 return;
4052 
4053         /*
4054          * First, let the device know about the exit latencies
4055          * associated with the link state we're about to enable.
4056          */
4057         ret = usb_req_set_sel(udev, state);
4058         if (ret < 0) {
4059                 dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n",
4060                                 usb3_lpm_names[state]);
4061                 return;
4062         }
4063 
4064         /* We allow the host controller to set the U1/U2 timeout internally
4065          * first, so that it can change its schedule to account for the
4066          * additional latency to send data to a device in a lower power
4067          * link state.
4068          */
4069         timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4070 
4071         /* xHCI host controller doesn't want to enable this LPM state. */
4072         if (timeout == 0)
4073                 return;
4074 
4075         if (timeout < 0) {
4076                 dev_warn(&udev->dev, "Could not enable %s link state, "
4077                                 "xHCI error %i.\n", usb3_lpm_names[state],
4078                                 timeout);
4079                 return;
4080         }
4081 
4082         if (usb_set_lpm_timeout(udev, state, timeout)) {
4083                 /* If we can't set the parent hub U1/U2 timeout,
4084                  * device-initiated LPM won't be allowed either, so let the xHCI
4085                  * host know that this link state won't be enabled.
4086                  */
4087                 hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4088                 return;
4089         }
4090 
4091         /* Only a configured device will accept the Set Feature
4092          * U1/U2_ENABLE
4093          */
4094         if (udev->actconfig &&
4095             usb_set_device_initiated_lpm(udev, state, true) == 0) {
4096                 if (state == USB3_LPM_U1)
4097                         udev->usb3_lpm_u1_enabled = 1;
4098                 else if (state == USB3_LPM_U2)
4099                         udev->usb3_lpm_u2_enabled = 1;
4100         } else {
4101                 /* Don't request U1/U2 entry if the device
4102                  * cannot transition to U1/U2.
4103                  */
4104                 usb_set_lpm_timeout(udev, state, 0);
4105                 hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4106         }
4107 }
4108 
4109 /*
4110  * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4111  * U1/U2 entry.
4112  *
4113  * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4114  * If zero is returned, the parent will not allow the link to go into U1/U2.
4115  *
4116  * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4117  * it won't have an effect on the bus link state because the parent hub will
4118  * still disallow device-initiated U1/U2 entry.
4119  *
4120  * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4121  * possible.  The result will be slightly more bus bandwidth will be taken up
4122  * (to account for U1/U2 exit latency), but it should be harmless.
4123  */
4124 static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4125                 enum usb3_link_state state)
4126 {
4127         switch (state) {
4128         case USB3_LPM_U1:
4129         case USB3_LPM_U2:
4130                 break;
4131         default:
4132                 dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4133                                 __func__);
4134                 return -EINVAL;
4135         }
4136 
4137         if (usb_set_lpm_timeout(udev, state, 0))
4138                 return -EBUSY;
4139 
4140         usb_set_device_initiated_lpm(udev, state, false);
4141 
4142         if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4143                 dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4144                                 "bus schedule bandwidth may be impacted.\n",
4145                                 usb3_lpm_names[state]);
4146 
4147         /* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4148          * is disabled. Hub will disallows link to enter U1/U2 as well,
4149          * even device is initiating LPM. Hence LPM is disabled if hub LPM
4150          * timeout set to 0, no matter device-initiated LPM is disabled or
4151          * not.
4152          */
4153         if (state == USB3_LPM_U1)
4154                 udev->usb3_lpm_u1_enabled = 0;
4155         else if (state == USB3_LPM_U2)
4156                 udev->usb3_lpm_u2_enabled = 0;
4157 
4158         return 0;
4159 }
4160 
4161 /*
4162  * Disable hub-initiated and device-initiated U1 and U2 entry.
4163  * Caller must own the bandwidth_mutex.
4164  *
4165  * This will call usb_enable_lpm() on failure, which will decrement
4166  * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4167  */
4168 int usb_disable_lpm(struct usb_device *udev)
4169 {
4170         struct usb_hcd *hcd;
4171 
4172         if (!udev || !udev->parent ||
4173                         udev->speed < USB_SPEED_SUPER ||
4174                         !udev->lpm_capable ||
4175                         udev->state < USB_STATE_CONFIGURED)
4176                 return 0;
4177 
4178         hcd = bus_to_hcd(udev->bus);
4179         if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4180                 return 0;
4181 
4182         udev->lpm_disable_count++;
4183         if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4184                 return 0;
4185 
4186         /* If LPM is enabled, attempt to disable it. */
4187         if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4188                 goto enable_lpm;
4189         if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4190                 goto enable_lpm;
4191 
4192         return 0;
4193 
4194 enable_lpm:
4195         usb_enable_lpm(udev);
4196         return -EBUSY;
4197 }
4198 EXPORT_SYMBOL_GPL(usb_disable_lpm);
4199 
4200 /* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4201 int usb_unlocked_disable_lpm(struct usb_device *udev)
4202 {
4203         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4204         int ret;
4205 
4206         if (!hcd)
4207                 return -EINVAL;
4208 
4209         mutex_lock(hcd->bandwidth_mutex);
4210         ret = usb_disable_lpm(udev);
4211         mutex_unlock(hcd->bandwidth_mutex);
4212 
4213         return ret;
4214 }
4215 EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4216 
4217 /*
4218  * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4219  * xHCI host policy may prevent U1 or U2 from being enabled.
4220  *
4221  * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4222  * until the lpm_disable_count drops to zero.  Caller must own the
4223  * bandwidth_mutex.
4224  */
4225 void usb_enable_lpm(struct usb_device *udev)
4226 {
4227         struct usb_hcd *hcd;
4228         struct usb_hub *hub;
4229         struct usb_port *port_dev;
4230 
4231         if (!udev || !udev->parent ||
4232                         udev->speed < USB_SPEED_SUPER ||
4233                         !udev->lpm_capable ||
4234                         udev->state < USB_STATE_CONFIGURED)
4235                 return;
4236 
4237         udev->lpm_disable_count--;
4238         hcd = bus_to_hcd(udev->bus);
4239         /* Double check that we can both enable and disable LPM.
4240          * Device must be configured to accept set feature U1/U2 timeout.
4241          */
4242         if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4243                         !hcd->driver->disable_usb3_lpm_timeout)
4244                 return;
4245 
4246         if (udev->lpm_disable_count > 0)
4247                 return;
4248 
4249         hub = usb_hub_to_struct_hub(udev->parent);
4250         if (!hub)
4251                 return;
4252 
4253         port_dev = hub->ports[udev->portnum - 1];
4254 
4255         if (port_dev->usb3_lpm_u1_permit)
4256                 usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4257 
4258         if (port_dev->usb3_lpm_u2_permit)
4259                 usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4260 }
4261 EXPORT_SYMBOL_GPL(usb_enable_lpm);
4262 
4263 /* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4264 void usb_unlocked_enable_lpm(struct usb_device *udev)
4265 {
4266         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4267 
4268         if (!hcd)
4269                 return;
4270 
4271         mutex_lock(hcd->bandwidth_mutex);
4272         usb_enable_lpm(udev);
4273         mutex_unlock(hcd->bandwidth_mutex);
4274 }
4275 EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4276 
4277 /* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
4278 static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4279                                           struct usb_port *port_dev)
4280 {
4281         struct usb_device *udev = port_dev->child;
4282         int ret;
4283 
4284         if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4285                 ret = hub_set_port_link_state(hub, port_dev->portnum,
4286                                               USB_SS_PORT_LS_U0);
4287                 if (!ret) {
4288                         msleep(USB_RESUME_TIMEOUT);
4289                         ret = usb_disable_remote_wakeup(udev);
4290                 }
4291                 if (ret)
4292                         dev_warn(&udev->dev,
4293                                  "Port disable: can't disable remote wake\n");
4294                 udev->do_remote_wakeup = 0;
4295         }
4296 }
4297 
4298 #else   /* CONFIG_PM */
4299 
4300 #define hub_suspend             NULL
4301 #define hub_resume              NULL
4302 #define hub_reset_resume        NULL
4303 
4304 static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4305                                                  struct usb_port *port_dev) { }
4306 
4307 int usb_disable_lpm(struct usb_device *udev)
4308 {
4309         return 0;
4310 }
4311 EXPORT_SYMBOL_GPL(usb_disable_lpm);
4312 
4313 void usb_enable_lpm(struct usb_device *udev) { }
4314 EXPORT_SYMBOL_GPL(usb_enable_lpm);
4315 
4316 int usb_unlocked_disable_lpm(struct usb_device *udev)
4317 {
4318         return 0;
4319 }
4320 EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4321 
4322 void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4323 EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4324 
4325 int usb_disable_ltm(struct usb_device *udev)
4326 {
4327         return 0;
4328 }
4329 EXPORT_SYMBOL_GPL(usb_disable_ltm);
4330 
4331 void usb_enable_ltm(struct usb_device *udev) { }
4332 EXPORT_SYMBOL_GPL(usb_enable_ltm);
4333 
4334 static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4335                 u16 portstatus, u16 portchange)
4336 {
4337         return 0;
4338 }
4339 
4340 #endif  /* CONFIG_PM */
4341 
4342 /*
4343  * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4344  * a connection with a plugged-in cable but will signal the host when the cable
4345  * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4346  */
4347 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4348 {
4349         struct usb_port *port_dev = hub->ports[port1 - 1];
4350         struct usb_device *hdev = hub->hdev;
4351         int ret = 0;
4352 
4353         if (!hub->error) {
4354                 if (hub_is_superspeed(hub->hdev)) {
4355                         hub_usb3_port_prepare_disable(hub, port_dev);
4356                         ret = hub_set_port_link_state(hub, port_dev->portnum,
4357                                                       USB_SS_PORT_LS_U3);
4358                 } else {
4359                         ret = usb_clear_port_feature(hdev, port1,
4360                                         USB_PORT_FEAT_ENABLE);
4361                 }
4362         }
4363         if (port_dev->child && set_state)
4364                 usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4365         if (ret && ret != -ENODEV)
4366                 dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4367         return ret;
4368 }
4369 
4370 /*
4371  * usb_port_disable - disable a usb device's upstream port
4372  * @udev: device to disable
4373  * Context: @udev locked, must be able to sleep.
4374  *
4375  * Disables a USB device that isn't in active use.
4376  */
4377 int usb_port_disable(struct usb_device *udev)
4378 {
4379         struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4380 
4381         return hub_port_disable(hub, udev->portnum, 0);
4382 }
4383 
4384 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4385  *
4386  * Between connect detection and reset signaling there must be a delay
4387  * of 100ms at least for debounce and power-settling.  The corresponding
4388  * timer shall restart whenever the downstream port detects a disconnect.
4389  *
4390  * Apparently there are some bluetooth and irda-dongles and a number of
4391  * low-speed devices for which this debounce period may last over a second.
4392  * Not covered by the spec - but easy to deal with.
4393  *
4394  * This implementation uses a 1500ms total debounce timeout; if the
4395  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4396  * every 25ms for transient disconnects.  When the port status has been
4397  * unchanged for 100ms it returns the port status.
4398  */
4399 int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4400 {
4401         int ret;
4402         u16 portchange, portstatus;
4403         unsigned connection = 0xffff;
4404         int total_time, stable_time = 0;
4405         struct usb_port *port_dev = hub->ports[port1 - 1];
4406 
4407         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4408                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
4409                 if (ret < 0)
4410                         return ret;
4411 
4412                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4413                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4414                         if (!must_be_connected ||
4415                              (connection == USB_PORT_STAT_CONNECTION))
4416                                 stable_time += HUB_DEBOUNCE_STEP;
4417                         if (stable_time >= HUB_DEBOUNCE_STABLE)
4418                                 break;
4419                 } else {
4420                         stable_time = 0;
4421                         connection = portstatus & USB_PORT_STAT_CONNECTION;
4422                 }
4423 
4424                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
4425                         usb_clear_port_feature(hub->hdev, port1,
4426                                         USB_PORT_FEAT_C_CONNECTION);
4427                 }
4428 
4429                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4430                         break;
4431                 msleep(HUB_DEBOUNCE_STEP);
4432         }
4433 
4434         dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4435                         total_time, stable_time, portstatus);
4436 
4437         if (stable_time < HUB_DEBOUNCE_STABLE)
4438                 return -ETIMEDOUT;
4439         return portstatus;
4440 }
4441 
4442 void usb_ep0_reinit(struct usb_device *udev)
4443 {
4444         usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4445         usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4446         usb_enable_endpoint(udev, &udev->ep0, true);
4447 }
4448 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4449 
4450 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
4451 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
4452 
4453 static int hub_set_address(struct usb_device *udev, int devnum)
4454 {
4455         int retval;
4456         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4457 
4458         /*
4459          * The host controller will choose the device address,
4460          * instead of the core having chosen it earlier
4461          */
4462         if (!hcd->driver->address_device && devnum <= 1)
4463                 return -EINVAL;
4464         if (udev->state == USB_STATE_ADDRESS)
4465                 return 0;
4466         if (udev->state != USB_STATE_DEFAULT)
4467                 return -EINVAL;
4468         if (hcd->driver->address_device)
4469                 retval = hcd->driver->address_device(hcd, udev);
4470         else
4471                 retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4472                                 USB_REQ_SET_ADDRESS, 0, devnum, 0,
4473                                 NULL, 0, USB_CTRL_SET_TIMEOUT);
4474         if (retval == 0) {
4475                 update_devnum(udev, devnum);
4476                 /* Device now using proper address. */
4477                 usb_set_device_state(udev, USB_STATE_ADDRESS);
4478                 usb_ep0_reinit(udev);
4479         }
4480         return retval;
4481 }
4482 
4483 /*
4484  * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4485  * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4486  * enabled.
4487  *
4488  * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4489  * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4490  * support bit in the BOS descriptor.
4491  */
4492 static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4493 {
4494         struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4495         int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4496 
4497         if (!udev->usb2_hw_lpm_capable || !udev->bos)
4498                 return;
4499 
4500         if (hub)
4501                 connect_type = hub->ports[udev->portnum - 1]->connect_type;
4502 
4503         if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4504                         connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4505                 udev->usb2_hw_lpm_allowed = 1;
4506                 usb_enable_usb2_hardware_lpm(udev);
4507         }
4508 }
4509 
4510 static int hub_enable_device(struct usb_device *udev)
4511 {
4512         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4513 
4514         if (!hcd->driver->enable_device)
4515                 return 0;
4516         if (udev->state == USB_STATE_ADDRESS)
4517                 return 0;
4518         if (udev->state != USB_STATE_DEFAULT)
4519                 return -EINVAL;
4520 
4521         return hcd->driver->enable_device(hcd, udev);
4522 }
4523 
4524 /* Reset device, (re)assign address, get device descriptor.
4525  * Device connection must be stable, no more debouncing needed.
4526  * Returns device in USB_STATE_ADDRESS, except on error.
4527  *
4528  * If this is called for an already-existing device (as part of
4529  * usb_reset_and_verify_device), the caller must own the device lock and
4530  * the port lock.  For a newly detected device that is not accessible
4531  * through any global pointers, it's not necessary to lock the device,
4532  * but it is still necessary to lock the port.
4533  */
4534 static int
4535 hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4536                 int retry_counter)
4537 {
4538         struct usb_device       *hdev = hub->hdev;
4539         struct usb_hcd          *hcd = bus_to_hcd(hdev->bus);
4540         struct usb_port         *port_dev = hub->ports[port1 - 1];
4541         int                     retries, operations, retval, i;
4542         unsigned                delay = HUB_SHORT_RESET_TIME;
4543         enum usb_device_speed   oldspeed = udev->speed;
4544         const char              *speed;
4545         int                     devnum = udev->devnum;
4546         const char              *driver_name;
4547 
4548         /* root hub ports have a slightly longer reset period
4549          * (from USB 2.0 spec, section 7.1.7.5)
4550          */
4551         if (!hdev->parent) {
4552                 delay = HUB_ROOT_RESET_TIME;
4553                 if (port1 == hdev->bus->otg_port)
4554                         hdev->bus->b_hnp_enable = 0;
4555         }
4556 
4557         /* Some low speed devices have problems with the quick delay, so */
4558         /*  be a bit pessimistic with those devices. RHbug #23670 */
4559         if (oldspeed == USB_SPEED_LOW)
4560                 delay = HUB_LONG_RESET_TIME;
4561 
4562         mutex_lock(hcd->address0_mutex);
4563 
4564         /* Reset the device; full speed may morph to high speed */
4565         /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4566         retval = hub_port_reset(hub, port1, udev, delay, false);
4567         if (retval < 0)         /* error or disconnect */
4568                 goto fail;
4569         /* success, speed is known */
4570 
4571         retval = -ENODEV;
4572 
4573         /* Don't allow speed changes at reset, except usb 3.0 to faster */
4574         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4575             !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4576                 dev_dbg(&udev->dev, "device reset changed speed!\n");
4577                 goto fail;
4578         }
4579         oldspeed = udev->speed;
4580 
4581         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4582          * it's fixed size except for full speed devices.
4583          * For Wireless USB devices, ep0 max packet is always 512 (tho
4584          * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
4585          */
4586         switch (udev->speed) {
4587         case USB_SPEED_SUPER_PLUS:
4588         case USB_SPEED_SUPER:
4589         case USB_SPEED_WIRELESS:        /* fixed at 512 */
4590                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4591                 break;
4592         case USB_SPEED_HIGH:            /* fixed at 64 */
4593                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4594                 break;
4595         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
4596                 /* to determine the ep0 maxpacket size, try to read
4597                  * the device descriptor to get bMaxPacketSize0 and
4598                  * then correct our initial guess.
4599                  */
4600                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4601                 break;
4602         case USB_SPEED_LOW:             /* fixed at 8 */
4603                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4604                 break;
4605         default:
4606                 goto fail;
4607         }
4608 
4609         if (udev->speed == USB_SPEED_WIRELESS)
4610                 speed = "variable speed Wireless";
4611         else
4612                 speed = usb_speed_string(udev->speed);
4613 
4614         /*
4615          * The controller driver may be NULL if the controller device
4616          * is the middle device between platform device and roothub.
4617          * This middle device may not need a device driver due to
4618          * all hardware control can be at platform device driver, this
4619          * platform device is usually a dual-role USB controller device.
4620          */
4621         if (udev->bus->controller->driver)
4622                 driver_name = udev->bus->controller->driver->name;
4623         else
4624                 driver_name = udev->bus->sysdev->driver->name;
4625 
4626         if (udev->speed < USB_SPEED_SUPER)
4627                 dev_info(&udev->dev,
4628                                 "%s %s USB device number %d using %s\n",
4629                                 (udev->config) ? "reset" : "new", speed,
4630                                 devnum, driver_name);
4631 
4632         /* Set up TT records, if needed  */
4633         if (hdev->tt) {
4634                 udev->tt = hdev->tt;
4635                 udev->ttport = hdev->ttport;
4636         } else if (udev->speed != USB_SPEED_HIGH
4637                         && hdev->speed == USB_SPEED_HIGH) {
4638                 if (!hub->tt.hub) {
4639                         dev_err(&udev->dev, "parent hub has no TT\n");
4640                         retval = -EINVAL;
4641                         goto fail;
4642                 }
4643                 udev->tt = &hub->tt;
4644                 udev->ttport = port1;
4645         }
4646 
4647         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4648          * Because device hardware and firmware is sometimes buggy in
4649          * this area, and this is how Linux has done it for ages.
4650          * Change it cautiously.
4651          *
4652          * NOTE:  If use_new_scheme() is true we will start by issuing
4653          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4654          * so it may help with some non-standards-compliant devices.
4655          * Otherwise we start with SET_ADDRESS and then try to read the
4656          * first 8 bytes of the device descriptor to get the ep0 maxpacket
4657          * value.
4658          */
4659         for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4660                 bool did_new_scheme = false;
4661 
4662                 if (use_new_scheme(udev, retry_counter, port_dev)) {
4663                         struct usb_device_descriptor *buf;
4664                         int r = 0;
4665 
4666                         did_new_scheme = true;
4667                         retval = hub_enable_device(udev);
4668                         if (retval < 0) {
4669                                 dev_err(&udev->dev,
4670                                         "hub failed to enable device, error %d\n",
4671                                         retval);
4672                                 goto fail;
4673                         }
4674 
4675 #define GET_DESCRIPTOR_BUFSIZE  64
4676                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4677                         if (!buf) {
4678                                 retval = -ENOMEM;
4679                                 continue;
4680                         }
4681 
4682                         /* Retry on all errors; some devices are flakey.
4683                          * 255 is for WUSB devices, we actually need to use
4684                          * 512 (WUSB1.0[4.8.1]).
4685                          */
4686                         for (operations = 0; operations < 3; ++operations) {
4687                                 buf->bMaxPacketSize0 = 0;
4688                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
4689                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4690                                         USB_DT_DEVICE << 8, 0,
4691                                         buf, GET_DESCRIPTOR_BUFSIZE,
4692                                         initial_descriptor_timeout);
4693                                 switch (buf->bMaxPacketSize0) {
4694                                 case 8: case 16: case 32: case 64: case 255:
4695                                         if (buf->bDescriptorType ==
4696                                                         USB_DT_DEVICE) {
4697                                                 r = 0;
4698                                                 break;
4699                                         }
4700                                         /* FALL THROUGH */
4701                                 default:
4702                                         if (r == 0)
4703                                                 r = -EPROTO;
4704                                         break;
4705                                 }
4706                                 /*
4707                                  * Some devices time out if they are powered on
4708                                  * when already connected. They need a second
4709                                  * reset. But only on the first attempt,
4710                                  * lest we get into a time out/reset loop
4711                                  */
4712                                 if (r == 0 || (r == -ETIMEDOUT &&
4713                                                 retries == 0 &&
4714                                                 udev->speed > USB_SPEED_FULL))
4715                                         break;
4716                         }
4717                         udev->descriptor.bMaxPacketSize0 =
4718                                         buf->bMaxPacketSize0;
4719                         kfree(buf);
4720 
4721                         retval = hub_port_reset(hub, port1, udev, delay, false);
4722                         if (retval < 0)         /* error or disconnect */
4723                                 goto fail;
4724                         if (oldspeed != udev->speed) {
4725                                 dev_dbg(&udev->dev,
4726                                         "device reset changed speed!\n");
4727                                 retval = -ENODEV;
4728                                 goto fail;
4729                         }
4730                         if (r) {
4731                                 if (r != -ENODEV)
4732                                         dev_err(&udev->dev, "device descriptor read/64, error %d\n",
4733                                                         r);
4734                                 retval = -EMSGSIZE;
4735                                 continue;
4736                         }
4737 #undef GET_DESCRIPTOR_BUFSIZE
4738                 }
4739 
4740                 /*
4741                  * If device is WUSB, we already assigned an
4742                  * unauthorized address in the Connect Ack sequence;
4743                  * authorization will assign the final address.
4744                  */
4745                 if (udev->wusb == 0) {
4746                         for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
4747                                 retval = hub_set_address(udev, devnum);
4748                                 if (retval >= 0)
4749                                         break;
4750                                 msleep(200);
4751                         }
4752                         if (retval < 0) {
4753                                 if (retval != -ENODEV)
4754                                         dev_err(&udev->dev, "device not accepting address %d, error %d\n",
4755                                                         devnum, retval);
4756                                 goto fail;
4757                         }
4758                         if (udev->speed >= USB_SPEED_SUPER) {
4759                                 devnum = udev->devnum;
4760                                 dev_info(&udev->dev,
4761                                                 "%s SuperSpeed%s%s USB device number %d using %s\n",
4762                                                 (udev->config) ? "reset" : "new",
4763                                          (udev->speed == USB_SPEED_SUPER_PLUS) ?
4764                                                         "Plus Gen 2" : " Gen 1",
4765                                          (udev->rx_lanes == 2 && udev->tx_lanes == 2) ?
4766                                                         "x2" : "",
4767                                          devnum, driver_name);
4768                         }
4769 
4770                         /* cope with hardware quirkiness:
4771                          *  - let SET_ADDRESS settle, some device hardware wants it
4772                          *  - read ep0 maxpacket even for high and low speed,
4773                          */
4774                         msleep(10);
4775                         /* use_new_scheme() checks the speed which may have
4776                          * changed since the initial look so we cache the result
4777                          * in did_new_scheme
4778                          */
4779                         if (did_new_scheme)
4780                                 break;
4781                 }
4782 
4783                 retval = usb_get_device_descriptor(udev, 8);
4784                 if (retval < 8) {
4785                         if (retval != -ENODEV)
4786                                 dev_err(&udev->dev,
4787                                         "device descriptor read/8, error %d\n",
4788                                         retval);
4789                         if (retval >= 0)
4790                                 retval = -EMSGSIZE;
4791                 } else {
4792                         u32 delay;
4793 
4794                         retval = 0;
4795 
4796                         delay = udev->parent->hub_delay;
4797                         udev->hub_delay = min_t(u32, delay,
4798                                                 USB_TP_TRANSMISSION_DELAY_MAX);
4799                         retval = usb_set_isoch_delay(udev);
4800                         if (retval) {
4801                                 dev_dbg(&udev->dev,
4802                                         "Failed set isoch delay, error %d\n",
4803                                         retval);
4804                                 retval = 0;
4805                         }
4806                         break;
4807                 }
4808         }
4809         if (retval)
4810                 goto fail;
4811 
4812         /*
4813          * Some superspeed devices have finished the link training process
4814          * and attached to a superspeed hub port, but the device descriptor
4815          * got from those devices show they aren't superspeed devices. Warm
4816          * reset the port attached by the devices can fix them.
4817          */
4818         if ((udev->speed >= USB_SPEED_SUPER) &&
4819                         (le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
4820                 dev_err(&udev->dev, "got a wrong device descriptor, "
4821                                 "warm reset device\n");
4822                 hub_port_reset(hub, port1, udev,
4823                                 HUB_BH_RESET_TIME, true);
4824                 retval = -EINVAL;
4825                 goto fail;
4826         }
4827 
4828         if (udev->descriptor.bMaxPacketSize0 == 0xff ||
4829                         udev->speed >= USB_SPEED_SUPER)
4830                 i = 512;
4831         else
4832                 i = udev->descriptor.bMaxPacketSize0;
4833         if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
4834                 if (udev->speed == USB_SPEED_LOW ||
4835                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
4836                         dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
4837                         retval = -EMSGSIZE;
4838                         goto fail;
4839                 }
4840                 if (udev->speed == USB_SPEED_FULL)
4841                         dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
4842                 else
4843                         dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
4844                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
4845                 usb_ep0_reinit(udev);
4846         }
4847 
4848         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
4849         if (retval < (signed)sizeof(udev->descriptor)) {
4850                 if (retval != -ENODEV)
4851                         dev_err(&udev->dev, "device descriptor read/all, error %d\n",
4852                                         retval);
4853                 if (retval >= 0)
4854                         retval = -ENOMSG;
4855                 goto fail;
4856         }
4857 
4858         usb_detect_quirks(udev);
4859 
4860         if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
4861                 retval = usb_get_bos_descriptor(udev);
4862                 if (!retval) {
4863                         udev->lpm_capable = usb_device_supports_lpm(udev);
4864                         usb_set_lpm_parameters(udev);
4865                 }
4866         }
4867 
4868         retval = 0;
4869         /* notify HCD that we have a device connected and addressed */
4870         if (hcd->driver->update_device)
4871                 hcd->driver->update_device(hcd, udev);
4872         hub_set_initial_usb2_lpm_policy(udev);
4873 fail:
4874         if (retval) {
4875                 hub_port_disable(hub, port1, 0);
4876                 update_devnum(udev, devnum);    /* for disconnect processing */
4877         }
4878         mutex_unlock(hcd->address0_mutex);
4879         return retval;
4880 }
4881 
4882 static void
4883 check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
4884 {
4885         struct usb_qualifier_descriptor *qual;
4886         int                             status;
4887 
4888         if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
4889                 return;
4890 
4891         qual = kmalloc(sizeof *qual, GFP_KERNEL);
4892         if (qual == NULL)
4893                 return;
4894 
4895         status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
4896                         qual, sizeof *qual);
4897         if (status == sizeof *qual) {
4898                 dev_info(&udev->dev, "not running at top speed; "
4899                         "connect to a high speed hub\n");
4900                 /* hub LEDs are probably harder to miss than syslog */
4901                 if (hub->has_indicators) {
4902                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
4903                         queue_delayed_work(system_power_efficient_wq,
4904                                         &hub->leds, 0);
4905                 }
4906         }
4907         kfree(qual);
4908 }
4909 
4910 static unsigned
4911 hub_power_remaining(struct usb_hub *hub)
4912 {
4913         struct usb_device *hdev = hub->hdev;
4914         int remaining;
4915         int port1;
4916 
4917         if (!hub->limited_power)
4918                 return 0;
4919 
4920         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
4921         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
4922                 struct usb_port *port_dev = hub->ports[port1 - 1];
4923                 struct usb_device *udev = port_dev->child;
4924                 unsigned unit_load;
4925                 int delta;
4926 
4927                 if (!udev)
4928                         continue;
4929                 if (hub_is_superspeed(udev))
4930                         unit_load = 150;
4931                 else
4932                         unit_load = 100;
4933 
4934                 /*
4935                  * Unconfigured devices may not use more than one unit load,
4936                  * or 8mA for OTG ports
4937                  */
4938                 if (udev->actconfig)
4939                         delta = usb_get_max_power(udev, udev->actconfig);
4940                 else if (port1 != udev->bus->otg_port || hdev->parent)
4941                         delta = unit_load;
4942                 else
4943                         delta = 8;
4944                 if (delta > hub->mA_per_port)
4945                         dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
4946                                         delta, hub->mA_per_port);
4947                 remaining -= delta;
4948         }
4949         if (remaining < 0) {
4950                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
4951                         -remaining);
4952                 remaining = 0;
4953         }
4954         return remaining;
4955 }
4956 
4957 static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
4958                 u16 portchange)
4959 {
4960         int status = -ENODEV;
4961         int i;
4962         unsigned unit_load;
4963         struct usb_device *hdev = hub->hdev;
4964         struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
4965         struct usb_port *port_dev = hub->ports[port1 - 1];
4966         struct usb_device *udev = port_dev->child;
4967         static int unreliable_port = -1;
4968 
4969         /* Disconnect any existing devices under this port */
4970         if (udev) {
4971                 if (hcd->usb_phy && !hdev->parent)
4972                         usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
4973                 usb_disconnect(&port_dev->child);
4974         }
4975 
4976         /* We can forget about a "removed" device when there's a physical
4977          * disconnect or the connect status changes.
4978          */
4979         if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
4980                         (portchange & USB_PORT_STAT_C_CONNECTION))
4981                 clear_bit(port1, hub->removed_bits);
4982 
4983         if (portchange & (USB_PORT_STAT_C_CONNECTION |
4984                                 USB_PORT_STAT_C_ENABLE)) {
4985                 status = hub_port_debounce_be_stable(hub, port1);
4986                 if (status < 0) {
4987                         if (status != -ENODEV &&
4988                                 port1 != unreliable_port &&
4989                                 printk_ratelimit())
4990                                 dev_err(&port_dev->dev, "connect-debounce failed\n");
4991                         portstatus &= ~USB_PORT_STAT_CONNECTION;
4992                         unreliable_port = port1;
4993                 } else {
4994                         portstatus = status;
4995                 }
4996         }
4997 
4998         /* Return now if debouncing failed or nothing is connected or
4999          * the device was "removed".
5000          */
5001         if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5002                         test_bit(port1, hub->removed_bits)) {
5003 
5004                 /*
5005                  * maybe switch power back on (e.g. root hub was reset)
5006                  * but only if the port isn't owned by someone else.
5007                  */
5008                 if (hub_is_port_power_switchable(hub)
5009                                 && !port_is_power_on(hub, portstatus)
5010                                 && !port_dev->port_owner)
5011                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
5012 
5013                 if (portstatus & USB_PORT_STAT_ENABLE)
5014                         goto done;
5015                 return;
5016         }
5017         if (hub_is_superspeed(hub->hdev))
5018                 unit_load = 150;
5019         else
5020                 unit_load = 100;
5021 
5022         status = 0;
5023         for (i = 0; i < SET_CONFIG_TRIES; i++) {
5024 
5025                 /* reallocate for each attempt, since references
5026                  * to the previous one can escape in various ways
5027                  */
5028                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
5029                 if (!udev) {
5030                         dev_err(&port_dev->dev,
5031                                         "couldn't allocate usb_device\n");
5032                         goto done;
5033                 }
5034 
5035                 usb_set_device_state(udev, USB_STATE_POWERED);
5036                 udev->bus_mA = hub->mA_per_port;
5037                 udev->level = hdev->level + 1;
5038                 udev->wusb = hub_is_wusb(hub);
5039 
5040                 /* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5041                 if (hub_is_superspeed(hub->hdev))
5042                         udev->speed = USB_SPEED_SUPER;
5043                 else
5044                         udev->speed = USB_SPEED_UNKNOWN;
5045 
5046                 choose_devnum(udev);
5047                 if (udev->devnum <= 0) {
5048                         status = -ENOTCONN;     /* Don't retry */
5049                         goto loop;
5050                 }
5051 
5052                 /* reset (non-USB 3.0 devices) and get descriptor */
5053                 usb_lock_port(port_dev);
5054                 status = hub_port_init(hub, udev, port1, i);
5055                 usb_unlock_port(port_dev);
5056                 if (status < 0)
5057                         goto loop;
5058 
5059                 if (udev->quirks & USB_QUIRK_DELAY_INIT)
5060                         msleep(2000);
5061 
5062                 /* consecutive bus-powered hubs aren't reliable; they can
5063                  * violate the voltage drop budget.  if the new child has
5064                  * a "powered" LED, users should notice we didn't enable it
5065                  * (without reading syslog), even without per-port LEDs
5066                  * on the parent.
5067                  */
5068                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5069                                 && udev->bus_mA <= unit_load) {
5070                         u16     devstat;
5071 
5072                         status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5073                                         &devstat);
5074                         if (status) {
5075                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
5076                                 goto loop_disable;
5077                         }
5078                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5079                                 dev_err(&udev->dev,
5080                                         "can't connect bus-powered hub "
5081                                         "to this port\n");
5082                                 if (hub->has_indicators) {
5083                                         hub->indicator[port1-1] =
5084                                                 INDICATOR_AMBER_BLINK;
5085                                         queue_delayed_work(
5086                                                 system_power_efficient_wq,
5087                                                 &hub->leds, 0);
5088                                 }
5089                                 status = -ENOTCONN;     /* Don't retry */
5090                                 goto loop_disable;
5091                         }
5092                 }
5093 
5094                 /* check for devices running slower than they could */
5095                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5096                                 && udev->speed == USB_SPEED_FULL
5097                                 && highspeed_hubs != 0)
5098                         check_highspeed(hub, udev, port1);
5099 
5100                 /* Store the parent's children[] pointer.  At this point
5101                  * udev becomes globally accessible, although presumably
5102                  * no one will look at it until hdev is unlocked.
5103                  */
5104                 status = 0;
5105 
5106                 mutex_lock(&usb_port_peer_mutex);
5107 
5108                 /* We mustn't add new devices if the parent hub has
5109                  * been disconnected; we would race with the
5110                  * recursively_mark_NOTATTACHED() routine.
5111                  */
5112                 spin_lock_irq(&device_state_lock);
5113                 if (hdev->state == USB_STATE_NOTATTACHED)
5114                         status = -ENOTCONN;
5115                 else
5116                         port_dev->child = udev;
5117                 spin_unlock_irq(&device_state_lock);
5118                 mutex_unlock(&usb_port_peer_mutex);
5119 
5120                 /* Run it through the hoops (find a driver, etc) */
5121                 if (!status) {
5122                         status = usb_new_device(udev);
5123                         if (status) {
5124                                 mutex_lock(&usb_port_peer_mutex);
5125                                 spin_lock_irq(&device_state_lock);
5126                                 port_dev->child = NULL;
5127                                 spin_unlock_irq(&device_state_lock);
5128                                 mutex_unlock(&usb_port_peer_mutex);
5129                         } else {
5130                                 if (hcd->usb_phy && !hdev->parent)
5131                                         usb_phy_notify_connect(hcd->usb_phy,
5132                                                         udev->speed);
5133                         }
5134                 }
5135 
5136                 if (status)
5137                         goto loop_disable;
5138 
5139                 status = hub_power_remaining(hub);
5140                 if (status)
5141                         dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5142 
5143                 return;
5144 
5145 loop_disable:
5146                 hub_port_disable(hub, port1, 1);
5147 loop:
5148                 usb_ep0_reinit(udev);
5149                 release_devnum(udev);
5150                 hub_free_dev(udev);
5151                 usb_put_dev(udev);
5152                 if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5153                         break;
5154 
5155                 /* When halfway through our retry count, power-cycle the port */
5156                 if (i == (SET_CONFIG_TRIES / 2) - 1) {
5157                         dev_info(&port_dev->dev, "attempt power cycle\n");
5158                         usb_hub_set_port_power(hdev, hub, port1, false);
5159                         msleep(2 * hub_power_on_good_delay(hub));
5160                         usb_hub_set_port_power(hdev, hub, port1, true);
5161                         msleep(hub_power_on_good_delay(hub));
5162                 }
5163         }
5164         if (hub->hdev->parent ||
5165                         !hcd->driver->port_handed_over ||
5166                         !(hcd->driver->port_handed_over)(hcd, port1)) {
5167                 if (status != -ENOTCONN && status != -ENODEV)
5168                         dev_err(&port_dev->dev,
5169                                         "unable to enumerate USB device\n");
5170         }
5171 
5172 done:
5173         hub_port_disable(hub, port1, 1);
5174         if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5175                 if (status != -ENOTCONN && status != -ENODEV)
5176                         hcd->driver->relinquish_port(hcd, port1);
5177         }
5178 }
5179 
5180 /* Handle physical or logical connection change events.
5181  * This routine is called when:
5182  *      a port connection-change occurs;
5183  *      a port enable-change occurs (often caused by EMI);
5184  *      usb_reset_and_verify_device() encounters changed descriptors (as from
5185  *              a firmware download)
5186  * caller already locked the hub
5187  */
5188 static void hub_port_connect_change(struct usb_hub *hub, int port1,
5189                                         u16 portstatus, u16 portchange)
5190                 __must_hold(&port_dev->status_lock)
5191 {
5192         struct usb_port *port_dev = hub->ports[port1 - 1];
5193         struct usb_device *udev = port_dev->child;
5194         int status = -ENODEV;
5195 
5196         dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5197                         portchange, portspeed(hub, portstatus));
5198 
5199         if (hub->has_indicators) {
5200                 set_port_led(hub, port1, HUB_LED_AUTO);
5201                 hub->indicator[port1-1] = INDICATOR_AUTO;
5202         }
5203 
5204 #ifdef  CONFIG_USB_OTG
5205         /* during HNP, don't repeat the debounce */
5206         if (hub->hdev->bus->is_b_host)
5207                 portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5208                                 USB_PORT_STAT_C_ENABLE);
5209 #endif
5210 
5211         /* Try to resuscitate an existing device */
5212         if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5213                         udev->state != USB_STATE_NOTATTACHED) {
5214                 if (portstatus & USB_PORT_STAT_ENABLE) {
5215                         status = 0;             /* Nothing to do */
5216 #ifdef CONFIG_PM
5217                 } else if (udev->state == USB_STATE_SUSPENDED &&
5218                                 udev->persist_enabled) {
5219                         /* For a suspended device, treat this as a
5220                          * remote wakeup event.
5221                          */
5222                         usb_unlock_port(port_dev);
5223                         status = usb_remote_wakeup(udev);
5224                         usb_lock_port(port_dev);
5225 #endif
5226                 } else {
5227                         /* Don't resuscitate */;
5228                 }
5229         }
5230         clear_bit(port1, hub->change_bits);
5231 
5232         /* successfully revalidated the connection */
5233         if (status == 0)
5234                 return;
5235 
5236         usb_unlock_port(port_dev);
5237         hub_port_connect(hub, port1, portstatus, portchange);
5238         usb_lock_port(port_dev);
5239 }
5240 
5241 /* Handle notifying userspace about hub over-current events */
5242 static void port_over_current_notify(struct usb_port *port_dev)
5243 {
5244         char *envp[3];
5245         struct device *hub_dev;
5246         char *port_dev_path;
5247 
5248         sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5249 
5250         hub_dev = port_dev->dev.parent;
5251 
5252         if (!hub_dev)
5253                 return;
5254 
5255         port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5256         if (!port_dev_path)
5257                 return;
5258 
5259         envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5260         if (!envp[0])
5261                 goto exit_path;
5262 
5263         envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5264                         port_dev->over_current_count);
5265         if (!envp[1])
5266                 goto exit;
5267 
5268         envp[2] = NULL;
5269         kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5270 
5271         kfree(envp[1]);
5272 exit:
5273         kfree(envp[0]);
5274 exit_path:
5275         kfree(port_dev_path);
5276 }
5277 
5278 static void port_event(struct usb_hub *hub, int port1)
5279                 __must_hold(&port_dev->status_lock)
5280 {
5281         int connect_change;
5282         struct usb_port *port_dev = hub->ports[port1 - 1];
5283         struct usb_device *udev = port_dev->child;
5284         struct usb_device *hdev = hub->hdev;
5285         u16 portstatus, portchange;
5286 
5287         connect_change = test_bit(port1, hub->change_bits);
5288         clear_bit(port1, hub->event_bits);
5289         clear_bit(port1, hub->wakeup_bits);
5290 
5291         if (hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5292                 return;
5293 
5294         if (portchange & USB_PORT_STAT_C_CONNECTION) {
5295                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5296                 connect_change = 1;
5297         }
5298 
5299         if (portchange & USB_PORT_STAT_C_ENABLE) {
5300                 if (!connect_change)
5301                         dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5302                                         portstatus);
5303                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5304 
5305                 /*
5306                  * EM interference sometimes causes badly shielded USB devices
5307                  * to be shutdown by the hub, this hack enables them again.
5308                  * Works at least with mouse driver.
5309                  */
5310                 if (!(portstatus & USB_PORT_STAT_ENABLE)
5311                     && !connect_change && udev) {
5312                         dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5313                         connect_change = 1;
5314                 }
5315         }
5316 
5317         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5318                 u16 status = 0, unused;
5319                 port_dev->over_current_count++;
5320                 port_over_current_notify(port_dev);
5321 
5322                 dev_dbg(&port_dev->dev, "over-current change #%u\n",
5323                         port_dev->over_current_count);
5324                 usb_clear_port_feature(hdev, port1,
5325                                 USB_PORT_FEAT_C_OVER_CURRENT);
5326                 msleep(100);    /* Cool down */
5327                 hub_power_on(hub, true);
5328                 hub_port_status(hub, port1, &status, &unused);
5329                 if (status & USB_PORT_STAT_OVERCURRENT)
5330                         dev_err(&port_dev->dev, "over-current condition\n");
5331         }
5332 
5333         if (portchange & USB_PORT_STAT_C_RESET) {
5334                 dev_dbg(&port_dev->dev, "reset change\n");
5335                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5336         }
5337         if ((portchange & USB_PORT_STAT_C_BH_RESET)
5338             && hub_is_superspeed(hdev)) {
5339                 dev_dbg(&port_dev->dev, "warm reset change\n");
5340                 usb_clear_port_feature(hdev, port1,
5341                                 USB_PORT_FEAT_C_BH_PORT_RESET);
5342         }
5343         if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5344                 dev_dbg(&port_dev->dev, "link state change\n");
5345                 usb_clear_port_feature(hdev, port1,
5346                                 USB_PORT_FEAT_C_PORT_LINK_STATE);
5347         }
5348         if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5349                 dev_warn(&port_dev->dev, "config error\n");
5350                 usb_clear_port_feature(hdev, port1,
5351                                 USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5352         }
5353 
5354         /* skip port actions that require the port to be powered on */
5355         if (!pm_runtime_active(&port_dev->dev))
5356                 return;
5357 
5358         if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5359                 connect_change = 1;
5360 
5361         /*
5362          * Warm reset a USB3 protocol port if it's in
5363          * SS.Inactive state.
5364          */
5365         if (hub_port_warm_reset_required(hub, port1, portstatus)) {
5366                 dev_dbg(&port_dev->dev, "do warm reset\n");
5367                 if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5368                                 || udev->state == USB_STATE_NOTATTACHED) {
5369                         if (hub_port_reset(hub, port1, NULL,
5370                                         HUB_BH_RESET_TIME, true) < 0)
5371                                 hub_port_disable(hub, port1, 1);
5372                 } else {
5373                         usb_unlock_port(port_dev);
5374                         usb_lock_device(udev);
5375                         usb_reset_device(udev);
5376                         usb_unlock_device(udev);
5377                         usb_lock_port(port_dev);
5378                         connect_change = 0;
5379                 }
5380         }
5381 
5382         if (connect_change)
5383                 hub_port_connect_change(hub, port1, portstatus, portchange);
5384 }
5385 
5386 static void hub_event(struct work_struct *work)
5387 {
5388         struct usb_device *hdev;
5389         struct usb_interface *intf;
5390         struct usb_hub *hub;
5391         struct device *hub_dev;
5392         u16 hubstatus;
5393         u16 hubchange;
5394         int i, ret;
5395 
5396         hub = container_of(work, struct usb_hub, events);
5397         hdev = hub->hdev;
5398         hub_dev = hub->intfdev;
5399         intf = to_usb_interface(hub_dev);
5400 
5401         dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5402                         hdev->state, hdev->maxchild,
5403                         /* NOTE: expects max 15 ports... */
5404                         (u16) hub->change_bits[0],
5405                         (u16) hub->event_bits[0]);
5406 
5407         /* Lock the device, then check to see if we were
5408          * disconnected while waiting for the lock to succeed. */
5409         usb_lock_device(hdev);
5410         if (unlikely(hub->disconnected))
5411                 goto out_hdev_lock;
5412 
5413         /* If the hub has died, clean up after it */
5414         if (hdev->state == USB_STATE_NOTATTACHED) {
5415                 hub->error = -ENODEV;
5416                 hub_quiesce(hub, HUB_DISCONNECT);
5417                 goto out_hdev_lock;
5418         }
5419 
5420         /* Autoresume */
5421         ret = usb_autopm_get_interface(intf);
5422         if (ret) {
5423                 dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5424                 goto out_hdev_lock;
5425         }
5426 
5427         /* If this is an inactive hub, do nothing */
5428         if (hub->quiescing)
5429                 goto out_autopm;
5430 
5431         if (hub->error) {
5432                 dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5433 
5434                 ret = usb_reset_device(hdev);
5435                 if (ret) {
5436                         dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5437                         goto out_autopm;
5438                 }
5439 
5440                 hub->nerrors = 0;
5441                 hub->error = 0;
5442         }
5443 
5444         /* deal with port status changes */
5445         for (i = 1; i <= hdev->maxchild; i++) {
5446                 struct usb_port *port_dev = hub->ports[i - 1];
5447 
5448                 if (test_bit(i, hub->event_bits)
5449                                 || test_bit(i, hub->change_bits)
5450                                 || test_bit(i, hub->wakeup_bits)) {
5451                         /*
5452                          * The get_noresume and barrier ensure that if
5453                          * the port was in the process of resuming, we
5454                          * flush that work and keep the port active for
5455                          * the duration of the port_event().  However,
5456                          * if the port is runtime pm suspended
5457                          * (powered-off), we leave it in that state, run
5458                          * an abbreviated port_event(), and move on.
5459                          */
5460                         pm_runtime_get_noresume(&port_dev->dev);
5461                         pm_runtime_barrier(&port_dev->dev);
5462                         usb_lock_port(port_dev);
5463                         port_event(hub, i);
5464                         usb_unlock_port(port_dev);
5465                         pm_runtime_put_sync(&port_dev->dev);
5466                 }
5467         }
5468 
5469         /* deal with hub status changes */
5470         if (test_and_clear_bit(0, hub->event_bits) == 0)
5471                 ;       /* do nothing */
5472         else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5473                 dev_err(hub_dev, "get_hub_status failed\n");
5474         else {
5475                 if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5476                         dev_dbg(hub_dev, "power change\n");
5477                         clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5478                         if (hubstatus & HUB_STATUS_LOCAL_POWER)
5479                                 /* FIXME: Is this always true? */
5480                                 hub->limited_power = 1;
5481                         else
5482                                 hub->limited_power = 0;
5483                 }
5484                 if (hubchange & HUB_CHANGE_OVERCURRENT) {
5485                         u16 status = 0;
5486                         u16 unused;
5487 
5488                         dev_dbg(hub_dev, "over-current change\n");
5489                         clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5490                         msleep(500);    /* Cool down */
5491                         hub_power_on(hub, true);
5492                         hub_hub_status(hub, &status, &unused);
5493                         if (status & HUB_STATUS_OVERCURRENT)
5494                                 dev_err(hub_dev, "over-current condition\n");
5495                 }
5496         }
5497 
5498 out_autopm:
5499         /* Balance the usb_autopm_get_interface() above */
5500         usb_autopm_put_interface_no_suspend(intf);
5501 out_hdev_lock:
5502         usb_unlock_device(hdev);
5503 
5504         /* Balance the stuff in kick_hub_wq() and allow autosuspend */
5505         usb_autopm_put_interface(intf);
5506         kref_put(&hub->kref, hub_release);
5507 }
5508 
5509 static const struct usb_device_id hub_id_table[] = {
5510     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5511                    | USB_DEVICE_ID_MATCH_PRODUCT
5512                    | USB_DEVICE_ID_MATCH_INT_CLASS,
5513       .idVendor = USB_VENDOR_SMSC,
5514       .idProduct = USB_PRODUCT_USB5534B,
5515       .bInterfaceClass = USB_CLASS_HUB,
5516       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5517     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5518                         | USB_DEVICE_ID_MATCH_INT_CLASS,
5519       .idVendor = USB_VENDOR_GENESYS_LOGIC,
5520       .bInterfaceClass = USB_CLASS_HUB,
5521       .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5522     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5523       .bDeviceClass = USB_CLASS_HUB},
5524     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5525       .bInterfaceClass = USB_CLASS_HUB},
5526     { }                                         /* Terminating entry */
5527 };
5528 
5529 MODULE_DEVICE_TABLE(usb, hub_id_table);
5530 
5531 static struct usb_driver hub_driver = {
5532         .name =         "hub",
5533         .probe =        hub_probe,
5534         .disconnect =   hub_disconnect,
5535         .suspend =      hub_suspend,
5536         .resume =       hub_resume,
5537         .reset_resume = hub_reset_resume,
5538         .pre_reset =    hub_pre_reset,
5539         .post_reset =   hub_post_reset,
5540         .unlocked_ioctl = hub_ioctl,
5541         .id_table =     hub_id_table,
5542         .supports_autosuspend = 1,
5543 };
5544 
5545 int usb_hub_init(void)
5546 {
5547         if (usb_register(&hub_driver) < 0) {
5548                 printk(KERN_ERR "%s: can't register hub driver\n",
5549                         usbcore_name);
5550                 return -1;
5551         }
5552 
5553         /*
5554          * The workqueue needs to be freezable to avoid interfering with
5555          * USB-PERSIST port handover. Otherwise it might see that a full-speed
5556          * device was gone before the EHCI controller had handed its port
5557          * over to the companion full-speed controller.
5558          */
5559         hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
5560         if (hub_wq)
5561                 return 0;
5562 
5563         /* Fall through if kernel_thread failed */
5564         usb_deregister(&hub_driver);
5565         pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
5566 
5567         return -1;
5568 }
5569 
5570 void usb_hub_cleanup(void)
5571 {
5572         destroy_workqueue(hub_wq);
5573 
5574         /*
5575          * Hub resources are freed for us by usb_deregister. It calls
5576          * usb_driver_purge on every device which in turn calls that
5577          * devices disconnect function if it is using this driver.
5578          * The hub_disconnect function takes care of releasing the
5579          * individual hub resources. -greg
5580          */
5581         usb_deregister(&hub_driver);
5582 } /* usb_hub_cleanup() */
5583 
5584 static int descriptors_changed(struct usb_device *udev,
5585                 struct usb_device_descriptor *old_device_descriptor,
5586                 struct usb_host_bos *old_bos)
5587 {
5588         int             changed = 0;
5589         unsigned        index;
5590         unsigned        serial_len = 0;
5591         unsigned        len;
5592         unsigned        old_length;
5593         int             length;
5594         char            *buf;
5595 
5596         if (memcmp(&udev->descriptor, old_device_descriptor,
5597                         sizeof(*old_device_descriptor)) != 0)
5598                 return 1;
5599 
5600         if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5601                 return 1;
5602         if (udev->bos) {
5603                 len = le16_to_cpu(udev->bos->desc->wTotalLength);
5604                 if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5605                         return 1;
5606                 if (memcmp(udev->bos->desc, old_bos->desc, len))
5607                         return 1;
5608         }
5609 
5610         /* Since the idVendor, idProduct, and bcdDevice values in the
5611          * device descriptor haven't changed, we will assume the
5612          * Manufacturer and Product strings haven't changed either.
5613          * But the SerialNumber string could be different (e.g., a
5614          * different flash card of the same brand).
5615          */
5616         if (udev->serial)
5617                 serial_len = strlen(udev->serial) + 1;
5618 
5619         len = serial_len;
5620         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5621                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5622                 len = max(len, old_length);
5623         }
5624 
5625         buf = kmalloc(len, GFP_NOIO);
5626         if (!buf)
5627                 /* assume the worst */
5628                 return 1;
5629 
5630         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5631                 old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5632                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5633                                 old_length);
5634                 if (length != old_length) {
5635                         dev_dbg(&udev->dev, "config index %d, error %d\n",
5636                                         index, length);
5637                         changed = 1;
5638                         break;
5639                 }
5640                 if (memcmp(buf, udev->rawdescriptors[index], old_length)
5641                                 != 0) {
5642                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5643                                 index,
5644                                 ((struct usb_config_descriptor *) buf)->
5645                                         bConfigurationValue);
5646                         changed = 1;
5647                         break;
5648                 }
5649         }
5650 
5651         if (!changed && serial_len) {
5652                 length = usb_string(udev, udev->descriptor.iSerialNumber,
5653                                 buf, serial_len);
5654                 if (length + 1 != serial_len) {
5655                         dev_dbg(&udev->dev, "serial string error %d\n",
5656                                         length);
5657                         changed = 1;
5658                 } else if (memcmp(buf, udev->serial, length) != 0) {
5659                         dev_dbg(&udev->dev, "serial string changed\n");
5660                         changed = 1;
5661                 }
5662         }
5663 
5664         kfree(buf);
5665         return changed;
5666 }
5667 
5668 /**
5669  * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
5670  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5671  *
5672  * WARNING - don't use this routine to reset a composite device
5673  * (one with multiple interfaces owned by separate drivers)!
5674  * Use usb_reset_device() instead.
5675  *
5676  * Do a port reset, reassign the device's address, and establish its
5677  * former operating configuration.  If the reset fails, or the device's
5678  * descriptors change from their values before the reset, or the original
5679  * configuration and altsettings cannot be restored, a flag will be set
5680  * telling hub_wq to pretend the device has been disconnected and then
5681  * re-connected.  All drivers will be unbound, and the device will be
5682  * re-enumerated and probed all over again.
5683  *
5684  * Return: 0 if the reset succeeded, -ENODEV if the device has been
5685  * flagged for logical disconnection, or some other negative error code
5686  * if the reset wasn't even attempted.
5687  *
5688  * Note:
5689  * The caller must own the device lock and the port lock, the latter is
5690  * taken by usb_reset_device().  For example, it's safe to use
5691  * usb_reset_device() from a driver probe() routine after downloading
5692  * new firmware.  For calls that might not occur during probe(), drivers
5693  * should lock the device using usb_lock_device_for_reset().
5694  *
5695  * Locking exception: This routine may also be called from within an
5696  * autoresume handler.  Such usage won't conflict with other tasks
5697  * holding the device lock because these tasks should always call
5698  * usb_autopm_resume_device(), thereby preventing any unwanted
5699  * autoresume.  The autoresume handler is expected to have already
5700  * acquired the port lock before calling this routine.
5701  */
5702 static int usb_reset_and_verify_device(struct usb_device *udev)
5703 {
5704         struct usb_device               *parent_hdev = udev->parent;
5705         struct usb_hub                  *parent_hub;
5706         struct usb_hcd                  *hcd = bus_to_hcd(udev->bus);
5707         struct usb_device_descriptor    descriptor = udev->descriptor;
5708         struct usb_host_bos             *bos;
5709         int                             i, j, ret = 0;
5710         int                             port1 = udev->portnum;
5711 
5712         if (udev->state == USB_STATE_NOTATTACHED ||
5713                         udev->state == USB_STATE_SUSPENDED) {
5714                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5715                                 udev->state);
5716                 return -EINVAL;
5717         }
5718 
5719         if (!parent_hdev)
5720                 return -EISDIR;
5721 
5722         parent_hub = usb_hub_to_struct_hub(parent_hdev);
5723 
5724         /* Disable USB2 hardware LPM.
5725          * It will be re-enabled by the enumeration process.
5726          */
5727         usb_disable_usb2_hardware_lpm(udev);
5728 
5729         /* Disable LPM while we reset the device and reinstall the alt settings.
5730          * Device-initiated LPM, and system exit latency settings are cleared
5731          * when the device is reset, so we have to set them up again.
5732          */
5733         ret = usb_unlocked_disable_lpm(udev);
5734         if (ret) {
5735                 dev_err(&udev->dev, "%s Failed to disable LPM\n", __func__);
5736                 goto re_enumerate_no_bos;
5737         }
5738 
5739         bos = udev->bos;
5740         udev->bos = NULL;
5741 
5742         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
5743 
5744                 /* ep0 maxpacket size may change; let the HCD know about it.
5745                  * Other endpoints will be handled by re-enumeration. */
5746                 usb_ep0_reinit(udev);
5747                 ret = hub_port_init(parent_hub, udev, port1, i);
5748                 if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
5749                         break;
5750         }
5751 
5752         if (ret < 0)
5753                 goto re_enumerate;
5754 
5755         /* Device might have changed firmware (DFU or similar) */
5756         if (descriptors_changed(udev, &descriptor, bos)) {
5757                 dev_info(&udev->dev, "device firmware changed\n");
5758                 udev->descriptor = descriptor;  /* for disconnect() calls */
5759                 goto re_enumerate;
5760         }
5761 
5762         /* Restore the device's previous configuration */
5763         if (!udev->actconfig)
5764                 goto done;
5765 
5766         mutex_lock(hcd->bandwidth_mutex);
5767         ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
5768         if (ret < 0) {
5769                 dev_warn(&udev->dev,
5770                                 "Busted HC?  Not enough HCD resources for "
5771                                 "old configuration.\n");
5772                 mutex_unlock(hcd->bandwidth_mutex);
5773                 goto re_enumerate;
5774         }
5775         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
5776                         USB_REQ_SET_CONFIGURATION, 0,
5777                         udev->actconfig->desc.bConfigurationValue, 0,
5778                         NULL, 0, USB_CTRL_SET_TIMEOUT);
5779         if (ret < 0) {
5780                 dev_err(&udev->dev,
5781                         "can't restore configuration #%d (error=%d)\n",
5782                         udev->actconfig->desc.bConfigurationValue, ret);
5783                 mutex_unlock(hcd->bandwidth_mutex);
5784                 goto re_enumerate;
5785         }
5786         mutex_unlock(hcd->bandwidth_mutex);
5787         usb_set_device_state(udev, USB_STATE_CONFIGURED);
5788 
5789         /* Put interfaces back into the same altsettings as before.
5790          * Don't bother to send the Set-Interface request for interfaces
5791          * that were already in altsetting 0; besides being unnecessary,
5792          * many devices can't handle it.  Instead just reset the host-side
5793          * endpoint state.
5794          */
5795         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
5796                 struct usb_host_config *config = udev->actconfig;
5797                 struct usb_interface *intf = config->interface[i];
5798                 struct usb_interface_descriptor *desc;
5799 
5800                 desc = &intf->cur_altsetting->desc;
5801                 if (desc->bAlternateSetting == 0) {
5802                         usb_disable_interface(udev, intf, true);
5803                         usb_enable_interface(udev, intf, true);
5804                         ret = 0;
5805                 } else {
5806                         /* Let the bandwidth allocation function know that this
5807                          * device has been reset, and it will have to use
5808                          * alternate setting 0 as the current alternate setting.
5809                          */
5810                         intf->resetting_device = 1;
5811                         ret = usb_set_interface(udev, desc->bInterfaceNumber,
5812                                         desc->bAlternateSetting);
5813                         intf->resetting_device = 0;
5814                 }
5815                 if (ret < 0) {
5816                         dev_err(&udev->dev, "failed to restore interface %d "
5817                                 "altsetting %d (error=%d)\n",
5818                                 desc->bInterfaceNumber,
5819                                 desc->bAlternateSetting,
5820                                 ret);
5821                         goto re_enumerate;
5822                 }
5823                 /* Resetting also frees any allocated streams */
5824                 for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
5825                         intf->cur_altsetting->endpoint[j].streams = 0;
5826         }
5827 
5828 done:
5829         /* Now that the alt settings are re-installed, enable LTM and LPM. */
5830         usb_enable_usb2_hardware_lpm(udev);
5831         usb_unlocked_enable_lpm(udev);
5832         usb_enable_ltm(udev);
5833         usb_release_bos_descriptor(udev);
5834         udev->bos = bos;
5835         return 0;
5836 
5837 re_enumerate:
5838         usb_release_bos_descriptor(udev);
5839         udev->bos = bos;
5840 re_enumerate_no_bos:
5841         /* LPM state doesn't matter when we're about to destroy the device. */
5842         hub_port_logical_disconnect(parent_hub, port1);
5843         return -ENODEV;
5844 }
5845 
5846 /**
5847  * usb_reset_device - warn interface drivers and perform a USB port reset
5848  * @udev: device to reset (not in NOTATTACHED state)
5849  *
5850  * Warns all drivers bound to registered interfaces (using their pre_reset
5851  * method), performs the port reset, and then lets the drivers know that
5852  * the reset is over (using their post_reset method).
5853  *
5854  * Return: The same as for usb_reset_and_verify_device().
5855  *
5856  * Note:
5857  * The caller must own the device lock.  For example, it's safe to use
5858  * this from a driver probe() routine after downloading new firmware.
5859  * For calls that might not occur during probe(), drivers should lock
5860  * the device using usb_lock_device_for_reset().
5861  *
5862  * If an interface is currently being probed or disconnected, we assume
5863  * its driver knows how to handle resets.  For all other interfaces,
5864  * if the driver doesn't have pre_reset and post_reset methods then
5865  * we attempt to unbind it and rebind afterward.
5866  */
5867 int usb_reset_device(struct usb_device *udev)
5868 {
5869         int ret;
5870         int i;
5871         unsigned int noio_flag;
5872         struct usb_port *port_dev;
5873         struct usb_host_config *config = udev->actconfig;
5874         struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
5875 
5876         if (udev->state == USB_STATE_NOTATTACHED) {
5877                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5878                                 udev->state);
5879                 return -EINVAL;
5880         }
5881 
5882         if (!udev->parent) {
5883                 /* this requires hcd-specific logic; see ohci_restart() */
5884                 dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
5885                 return -EISDIR;
5886         }
5887 
5888         port_dev = hub->ports[udev->portnum - 1];
5889 
5890         /*
5891          * Don't allocate memory with GFP_KERNEL in current
5892          * context to avoid possible deadlock if usb mass
5893          * storage interface or usbnet interface(iSCSI case)
5894          * is included in current configuration. The easist
5895          * approach is to do it for every device reset,
5896          * because the device 'memalloc_noio' flag may have
5897          * not been set before reseting the usb device.
5898          */
5899         noio_flag = memalloc_noio_save();
5900 
5901         /* Prevent autosuspend during the reset */
5902         usb_autoresume_device(udev);
5903 
5904         if (config) {
5905                 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
5906                         struct usb_interface *cintf = config->interface[i];
5907                         struct usb_driver *drv;
5908                         int unbind = 0;
5909 
5910                         if (cintf->dev.driver) {
5911                                 drv = to_usb_driver(cintf->dev.driver);
5912                                 if (drv->pre_reset && drv->post_reset)
5913                                         unbind = (drv->pre_reset)(cintf);
5914                                 else if (cintf->condition ==
5915                                                 USB_INTERFACE_BOUND)
5916                                         unbind = 1;
5917                                 if (unbind)
5918                                         usb_forced_unbind_intf(cintf);
5919                         }
5920                 }
5921         }
5922 
5923         usb_lock_port(port_dev);
5924         ret = usb_reset_and_verify_device(udev);
5925         usb_unlock_port(port_dev);
5926 
5927         if (config) {
5928                 for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
5929                         struct usb_interface *cintf = config->interface[i];
5930                         struct usb_driver *drv;
5931                         int rebind = cintf->needs_binding;
5932 
5933                         if (!rebind && cintf->dev.driver) {
5934                                 drv = to_usb_driver(cintf->dev.driver);
5935                                 if (drv->post_reset)
5936                                         rebind = (drv->post_reset)(cintf);
5937                                 else if (cintf->condition ==
5938                                                 USB_INTERFACE_BOUND)
5939                                         rebind = 1;
5940                                 if (rebind)
5941                                         cintf->needs_binding = 1;
5942                         }
5943                 }
5944 
5945                 /* If the reset failed, hub_wq will unbind drivers later */
5946                 if (ret == 0)
5947                         usb_unbind_and_rebind_marked_interfaces(udev);
5948         }
5949 
5950         usb_autosuspend_device(udev);
5951         memalloc_noio_restore(noio_flag);
5952         return ret;
5953 }
5954 EXPORT_SYMBOL_GPL(usb_reset_device);
5955 
5956 
5957 /**
5958  * usb_queue_reset_device - Reset a USB device from an atomic context
5959  * @iface: USB interface belonging to the device to reset
5960  *
5961  * This function can be used to reset a USB device from an atomic
5962  * context, where usb_reset_device() won't work (as it blocks).
5963  *
5964  * Doing a reset via this method is functionally equivalent to calling
5965  * usb_reset_device(), except for the fact that it is delayed to a
5966  * workqueue. This means that any drivers bound to other interfaces
5967  * might be unbound, as well as users from usbfs in user space.
5968  *
5969  * Corner cases:
5970  *
5971  * - Scheduling two resets at the same time from two different drivers
5972  *   attached to two different interfaces of the same device is
5973  *   possible; depending on how the driver attached to each interface
5974  *   handles ->pre_reset(), the second reset might happen or not.
5975  *
5976  * - If the reset is delayed so long that the interface is unbound from
5977  *   its driver, the reset will be skipped.
5978  *
5979  * - This function can be called during .probe().  It can also be called
5980  *   during .disconnect(), but doing so is pointless because the reset
5981  *   will not occur.  If you really want to reset the device during
5982  *   .disconnect(), call usb_reset_device() directly -- but watch out
5983  *   for nested unbinding issues!
5984  */
5985 void usb_queue_reset_device(struct usb_interface *iface)
5986 {
5987         if (schedule_work(&iface->reset_ws))
5988                 usb_get_intf(iface);
5989 }
5990 EXPORT_SYMBOL_GPL(usb_queue_reset_device);
5991 
5992 /**
5993  * usb_hub_find_child - Get the pointer of child device
5994  * attached to the port which is specified by @port1.
5995  * @hdev: USB device belonging to the usb hub
5996  * @port1: port num to indicate which port the child device
5997  *      is attached to.
5998  *
5999  * USB drivers call this function to get hub's child device
6000  * pointer.
6001  *
6002  * Return: %NULL if input param is invalid and
6003  * child's usb_device pointer if non-NULL.
6004  */
6005 struct usb_device *usb_hub_find_child(struct usb_device *hdev,
6006                 int port1)
6007 {
6008         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6009 
6010         if (port1 < 1 || port1 > hdev->maxchild)
6011                 return NULL;
6012         return hub->ports[port1 - 1]->child;
6013 }
6014 EXPORT_SYMBOL_GPL(usb_hub_find_child);
6015 
6016 void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
6017                 struct usb_hub_descriptor *desc)
6018 {
6019         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6020         enum usb_port_connect_type connect_type;
6021         int i;
6022 
6023         if (!hub)
6024                 return;
6025 
6026         if (!hub_is_superspeed(hdev)) {
6027                 for (i = 1; i <= hdev->maxchild; i++) {
6028                         struct usb_port *port_dev = hub->ports[i - 1];
6029 
6030                         connect_type = port_dev->connect_type;
6031                         if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6032                                 u8 mask = 1 << (i%8);
6033 
6034                                 if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6035                                         dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6036                                         desc->u.hs.DeviceRemovable[i/8] |= mask;
6037                                 }
6038                         }
6039                 }
6040         } else {
6041                 u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6042 
6043                 for (i = 1; i <= hdev->maxchild; i++) {
6044                         struct usb_port *port_dev = hub->ports[i - 1];
6045 
6046                         connect_type = port_dev->connect_type;
6047                         if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6048                                 u16 mask = 1 << i;
6049 
6050                                 if (!(port_removable & mask)) {
6051                                         dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6052                                         port_removable |= mask;
6053                                 }
6054                         }
6055                 }
6056 
6057                 desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6058         }
6059 }
6060 
6061 #ifdef CONFIG_ACPI
6062 /**
6063  * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6064  * @hdev: USB device belonging to the usb hub
6065  * @port1: port num of the port
6066  *
6067  * Return: Port's acpi handle if successful, %NULL if params are
6068  * invalid.
6069  */
6070 acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6071         int port1)
6072 {
6073         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6074 
6075         if (!hub)
6076                 return NULL;
6077 
6078         return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6079 }
6080 #endif