root/drivers/staging/uwb/hwa-rc.c

DEFINITIONS

1. hwarc_filter_evt_beacon_WUSB_0100
2. hwarc_filter_evt_drp_avail_WUSB_0100
3. hwarc_filter_evt_drp_WUSB_0100
4. hwarc_filter_cmd_scan_WUSB_0100
5. hwarc_filter_cmd_set_drp_ie_WUSB_0100
6. hwarc_filter_cmd_WUSB_0100
7. hwarc_filter_cmd
8. hwarc_get_event_size
9. hwarc_filter_event_WUSB_0100
10. hwarc_filter_event
11. hwarc_cmd
12. hwarc_reset
13. hwarc_neep_cb
14. hwarc_init
15. hwarc_neep_init
16. hwarc_neep_release
17. hwarc_get_version
18. hwarc_probe
19. hwarc_disconnect
20. hwarc_pre_reset
21. hwarc_post_reset

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * WUSB Host Wire Adapter: Radio Control Interface (WUSB[8.6])
   4  * Radio Control command/event transport
   5  *
   6  * Copyright (C) 2005-2006 Intel Corporation
   7  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   8  *
   9  * Initialize the Radio Control interface Driver.
  10  *
  11  * For each device probed, creates an 'struct hwarc' which contains
  12  * just the representation of the UWB Radio Controller, and the logic
  13  * for reading notifications and passing them to the UWB Core.
  14  *
  15  * So we initialize all of those, register the UWB Radio Controller
  16  * and setup the notification/event handle to pipe the notifications
  17  * to the UWB management Daemon.
  18  *
  19  * Command and event filtering.
  20  *
  21  * This is the driver for the Radio Control Interface described in WUSB
  22  * 1.0. The core UWB module assumes that all drivers are compliant to the
  23  * WHCI 0.95 specification. We thus create a filter that parses all
  24  * incoming messages from the (WUSB 1.0) device and manipulate them to
  25  * conform to the WHCI 0.95 specification. Similarly, outgoing messages
  26  * are parsed and manipulated to conform to the WUSB 1.0 compliant messages
  27  * that the device expects. Only a few messages are affected:
  28  * Affected events:
  29  *    UWB_RC_EVT_BEACON
  30  *    UWB_RC_EVT_BP_SLOT_CHANGE
  31  *    UWB_RC_EVT_DRP_AVAIL
  32  *    UWB_RC_EVT_DRP
  33  * Affected commands:
  34  *    UWB_RC_CMD_SCAN
  35  *    UWB_RC_CMD_SET_DRP_IE
  36  */
  37 #include <linux/init.h>
  38 #include <linux/module.h>
  39 #include <linux/slab.h>
  40 #include <linux/usb.h>
  41 #include "../wusbcore/include/wusb.h"
  42 #include "../wusbcore/include/wusb-wa.h"
  43 #include "uwb.h"
  44 
  45 #include "uwb-internal.h"
  46 
  47 /* The device uses commands and events from the WHCI specification, although
  48  * reporting itself as WUSB compliant. */
  49 #define WUSB_QUIRK_WHCI_CMD_EVT         0x01
  50 
  51 /**
  52  * Descriptor for an instance of the UWB Radio Control Driver that
  53  * attaches to the RCI interface of the Host Wired Adapter.
  54  *
  55  * Unless there is a lock specific to the 'data members', all access
  56  * is protected by uwb_rc->mutex.
  57  *
  58  * The NEEP (Notification/Event EndPoint) URB (@neep_urb) writes to
  59  * @rd_buffer. Note there is no locking because it is perfectly (heh!)
  60  * serialized--probe() submits an URB, callback is called, processes
  61  * the data (synchronously), submits another URB, and so on. There is
  62  * no concurrent access to the buffer.
  63  */
  64 struct hwarc {
  65         struct usb_device *usb_dev;
  66         struct usb_interface *usb_iface;
  67         struct uwb_rc *uwb_rc;          /* UWB host controller */
  68         struct urb *neep_urb;           /* Notification endpoint handling */
  69         struct edc neep_edc;
  70         void *rd_buffer;                /* NEEP read buffer */
  71 };
  72 
  73 
  74 /* Beacon received notification (WUSB 1.0 [8.6.3.2]) */
  75 struct uwb_rc_evt_beacon_WUSB_0100 {
  76         struct uwb_rceb rceb;
  77         u8      bChannelNumber;
  78         __le16  wBPSTOffset;
  79         u8      bLQI;
  80         u8      bRSSI;
  81         __le16  wBeaconInfoLength;
  82         u8      BeaconInfo[];
  83 } __attribute__((packed));
  84 
  85 /**
  86  * Filter WUSB 1.0 BEACON RCV notification to be WHCI 0.95
  87  *
  88  * @header: the incoming event
  89  * @buf_size: size of buffer containing incoming event
  90  * @new_size: size of event after filtering completed
  91  *
  92  * The WHCI 0.95 spec has a "Beacon Type" field. This value is unknown at
  93  * the time we receive the beacon from WUSB so we just set it to
  94  * UWB_RC_BEACON_TYPE_NEIGHBOR as a default.
  95  * The solution below allocates memory upon receipt of every beacon from a
  96  * WUSB device. This will deteriorate performance. What is the right way to
  97  * do this?
  98  */
  99 static
 100 int hwarc_filter_evt_beacon_WUSB_0100(struct uwb_rc *rc,
 101                                       struct uwb_rceb **header,
 102                                       const size_t buf_size,
 103                                       size_t *new_size)
 104 {
 105         struct uwb_rc_evt_beacon_WUSB_0100 *be;
 106         struct uwb_rc_evt_beacon *newbe;
 107         size_t bytes_left, ielength;
 108         struct device *dev = &rc->uwb_dev.dev;
 109 
 110         be = container_of(*header, struct uwb_rc_evt_beacon_WUSB_0100, rceb);
 111         bytes_left = buf_size;
 112         if (bytes_left < sizeof(*be)) {
 113                 dev_err(dev, "Beacon Received Notification: Not enough data "
 114                         "to decode for filtering (%zu vs %zu bytes needed)\n",
 115                         bytes_left, sizeof(*be));
 116                 return -EINVAL;
 117         }
 118         bytes_left -= sizeof(*be);
 119         ielength = le16_to_cpu(be->wBeaconInfoLength);
 120         if (bytes_left < ielength) {
 121                 dev_err(dev, "Beacon Received Notification: Not enough data "
 122                         "to decode IEs (%zu vs %zu bytes needed)\n",
 123                         bytes_left, ielength);
 124                 return -EINVAL;
 125         }
 126         newbe = kzalloc(sizeof(*newbe) + ielength, GFP_ATOMIC);
 127         if (newbe == NULL)
 128                 return -ENOMEM;
 129         newbe->rceb = be->rceb;
 130         newbe->bChannelNumber = be->bChannelNumber;
 131         newbe->bBeaconType = UWB_RC_BEACON_TYPE_NEIGHBOR;
 132         newbe->wBPSTOffset = be->wBPSTOffset;
 133         newbe->bLQI = be->bLQI;
 134         newbe->bRSSI = be->bRSSI;
 135         newbe->wBeaconInfoLength = be->wBeaconInfoLength;
 136         memcpy(newbe->BeaconInfo, be->BeaconInfo, ielength);
 137         *header = &newbe->rceb;
 138         *new_size = sizeof(*newbe) + ielength;
 139         return 1;  /* calling function will free memory */
 140 }
 141 
 142 
 143 /* DRP Availability change notification (WUSB 1.0 [8.6.3.8]) */
 144 struct uwb_rc_evt_drp_avail_WUSB_0100 {
 145         struct uwb_rceb rceb;
 146         __le16 wIELength;
 147         u8 IEData[];
 148 } __attribute__((packed));
 149 
 150 /**
 151  * Filter WUSB 1.0 DRP AVAILABILITY CHANGE notification to be WHCI 0.95
 152  *
 153  * @header: the incoming event
 154  * @buf_size: size of buffer containing incoming event
 155  * @new_size: size of event after filtering completed
 156  */
 157 static
 158 int hwarc_filter_evt_drp_avail_WUSB_0100(struct uwb_rc *rc,
 159                                          struct uwb_rceb **header,
 160                                          const size_t buf_size,
 161                                          size_t *new_size)
 162 {
 163         struct uwb_rc_evt_drp_avail_WUSB_0100 *da;
 164         struct uwb_rc_evt_drp_avail *newda;
 165         struct uwb_ie_hdr *ie_hdr;
 166         size_t bytes_left, ielength;
 167         struct device *dev = &rc->uwb_dev.dev;
 168 
 169 
 170         da = container_of(*header, struct uwb_rc_evt_drp_avail_WUSB_0100, rceb);
 171         bytes_left = buf_size;
 172         if (bytes_left < sizeof(*da)) {
 173                 dev_err(dev, "Not enough data to decode DRP Avail "
 174                         "Notification for filtering. Expected %zu, "
 175                         "received %zu.\n", (size_t)sizeof(*da), bytes_left);
 176                 return -EINVAL;
 177         }
 178         bytes_left -= sizeof(*da);
 179         ielength = le16_to_cpu(da->wIELength);
 180         if (bytes_left < ielength) {
 181                 dev_err(dev, "DRP Avail Notification filter: IE length "
 182                         "[%zu bytes] does not match actual length "
 183                         "[%zu bytes].\n", ielength, bytes_left);
 184                 return -EINVAL;
 185         }
 186         if (ielength < sizeof(*ie_hdr)) {
 187                 dev_err(dev, "DRP Avail Notification filter: Not enough "
 188                         "data to decode IE [%zu bytes, %zu needed]\n",
 189                         ielength, sizeof(*ie_hdr));
 190                 return -EINVAL;
 191         }
 192         ie_hdr = (void *) da->IEData;
 193         if (ie_hdr->length > 32) {
 194                 dev_err(dev, "DRP Availability Change event has unexpected "
 195                         "length for filtering. Expected < 32 bytes, "
 196                         "got %zu bytes.\n", (size_t)ie_hdr->length);
 197                 return -EINVAL;
 198         }
 199         newda = kzalloc(sizeof(*newda), GFP_ATOMIC);
 200         if (newda == NULL)
 201                 return -ENOMEM;
 202         newda->rceb = da->rceb;
 203         memcpy(newda->bmp, (u8 *) ie_hdr + sizeof(*ie_hdr), ie_hdr->length);
 204         *header = &newda->rceb;
 205         *new_size = sizeof(*newda);
 206         return 1; /* calling function will free memory */
 207 }
 208 
 209 
 210 /* DRP notification (WUSB 1.0 [8.6.3.9]) */
 211 struct uwb_rc_evt_drp_WUSB_0100 {
 212         struct uwb_rceb rceb;
 213         struct uwb_dev_addr wSrcAddr;
 214         u8 bExplicit;
 215         __le16 wIELength;
 216         u8 IEData[];
 217 } __attribute__((packed));
 218 
 219 /**
 220  * Filter WUSB 1.0 DRP Notification to be WHCI 0.95
 221  *
 222  * @header: the incoming event
 223  * @buf_size: size of buffer containing incoming event
 224  * @new_size: size of event after filtering completed
 225  *
 226  * It is hard to manage DRP reservations without having a Reason code.
 227  * Unfortunately there is none in the WUSB spec. We just set the default to
 228  * DRP IE RECEIVED.
 229  * We do not currently use the bBeaconSlotNumber value, so we set this to
 230  * zero for now.
 231  */
 232 static
 233 int hwarc_filter_evt_drp_WUSB_0100(struct uwb_rc *rc,
 234                                    struct uwb_rceb **header,
 235                                    const size_t buf_size,
 236                                    size_t *new_size)
 237 {
 238         struct uwb_rc_evt_drp_WUSB_0100 *drpev;
 239         struct uwb_rc_evt_drp *newdrpev;
 240         size_t bytes_left, ielength;
 241         struct device *dev = &rc->uwb_dev.dev;
 242 
 243         drpev = container_of(*header, struct uwb_rc_evt_drp_WUSB_0100, rceb);
 244         bytes_left = buf_size;
 245         if (bytes_left < sizeof(*drpev)) {
 246                 dev_err(dev, "Not enough data to decode DRP Notification "
 247                         "for filtering. Expected %zu, received %zu.\n",
 248                         (size_t)sizeof(*drpev), bytes_left);
 249                 return -EINVAL;
 250         }
 251         ielength = le16_to_cpu(drpev->wIELength);
 252         bytes_left -= sizeof(*drpev);
 253         if (bytes_left < ielength) {
 254                 dev_err(dev, "DRP Notification filter: header length [%zu "
 255                         "bytes] does not match actual length [%zu "
 256                         "bytes].\n", ielength, bytes_left);
 257                 return -EINVAL;
 258         }
 259         newdrpev = kzalloc(sizeof(*newdrpev) + ielength, GFP_ATOMIC);
 260         if (newdrpev == NULL)
 261                 return -ENOMEM;
 262         newdrpev->rceb = drpev->rceb;
 263         newdrpev->src_addr = drpev->wSrcAddr;
 264         newdrpev->reason = UWB_DRP_NOTIF_DRP_IE_RCVD;
 265         newdrpev->beacon_slot_number = 0;
 266         newdrpev->ie_length = drpev->wIELength;
 267         memcpy(newdrpev->ie_data, drpev->IEData, ielength);
 268         *header = &newdrpev->rceb;
 269         *new_size = sizeof(*newdrpev) + ielength;
 270         return 1; /* calling function will free memory */
 271 }
 272 
 273 
 274 /* Scan Command (WUSB 1.0 [8.6.2.5]) */
 275 struct uwb_rc_cmd_scan_WUSB_0100 {
 276         struct uwb_rccb rccb;
 277         u8 bChannelNumber;
 278         u8 bScanState;
 279 } __attribute__((packed));
 280 
 281 /**
 282  * Filter WHCI 0.95 SCAN command to be WUSB 1.0 SCAN command
 283  *
 284  * @header:   command sent to device (compliant to WHCI 0.95)
 285  * @size:     size of command sent to device
 286  *
 287  * We only reduce the size by two bytes because the WUSB 1.0 scan command
 288  * does not have the last field (wStarttime). Also, make sure we don't send
 289  * the device an unexpected scan type.
 290  */
 291 static
 292 int hwarc_filter_cmd_scan_WUSB_0100(struct uwb_rc *rc,
 293                                     struct uwb_rccb **header,
 294                                     size_t *size)
 295 {
 296         struct uwb_rc_cmd_scan *sc;
 297 
 298         sc = container_of(*header, struct uwb_rc_cmd_scan, rccb);
 299 
 300         if (sc->bScanState == UWB_SCAN_ONLY_STARTTIME)
 301                 sc->bScanState = UWB_SCAN_ONLY;
 302         /* Don't send the last two bytes. */
 303         *size -= 2;
 304         return 0;
 305 }
 306 
 307 
 308 /* SET DRP IE command (WUSB 1.0 [8.6.2.7]) */
 309 struct uwb_rc_cmd_set_drp_ie_WUSB_0100 {
 310         struct uwb_rccb rccb;
 311         u8 bExplicit;
 312         __le16 wIELength;
 313         struct uwb_ie_drp IEData[];
 314 } __attribute__((packed));
 315 
 316 /**
 317  * Filter WHCI 0.95 SET DRP IE command to be WUSB 1.0 SET DRP IE command
 318  *
 319  * @header:   command sent to device (compliant to WHCI 0.95)
 320  * @size:     size of command sent to device
 321  *
 322  * WUSB has an extra bExplicit field - we assume always explicit
 323  * negotiation so this field is set. The command expected by the device is
 324  * thus larger than the one prepared by the driver so we need to
 325  * reallocate memory to accommodate this.
 326  * We trust the driver to send us the correct data so no checking is done
 327  * on incoming data - evn though it is variable length.
 328  */
 329 static
 330 int hwarc_filter_cmd_set_drp_ie_WUSB_0100(struct uwb_rc *rc,
 331                                           struct uwb_rccb **header,
 332                                           size_t *size)
 333 {
 334         struct uwb_rc_cmd_set_drp_ie *orgcmd;
 335         struct uwb_rc_cmd_set_drp_ie_WUSB_0100 *cmd;
 336         size_t ielength;
 337 
 338         orgcmd = container_of(*header, struct uwb_rc_cmd_set_drp_ie, rccb);
 339         ielength = le16_to_cpu(orgcmd->wIELength);
 340         cmd = kzalloc(sizeof(*cmd) + ielength, GFP_KERNEL);
 341         if (cmd == NULL)
 342                 return -ENOMEM;
 343         cmd->rccb = orgcmd->rccb;
 344         cmd->bExplicit = 0;
 345         cmd->wIELength = orgcmd->wIELength;
 346         memcpy(cmd->IEData, orgcmd->IEData, ielength);
 347         *header = &cmd->rccb;
 348         *size = sizeof(*cmd) + ielength;
 349         return 1; /* calling function will free memory */
 350 }
 351 
 352 
 353 /**
 354  * Filter data from WHCI driver to WUSB device
 355  *
 356  * @header: WHCI 0.95 compliant command from driver
 357  * @size:   length of command
 358  *
 359  * The routine managing commands to the device (uwb_rc_cmd()) will call the
 360  * filtering function pointer (if it exists) before it passes any data to
 361  * the device. At this time the command has been formatted according to
 362  * WHCI 0.95 and is ready to be sent to the device.
 363  *
 364  * The filter function will be provided with the current command and its
 365  * length. The function will manipulate the command if necessary and
 366  * potentially reallocate memory for a command that needed more memory that
 367  * the given command. If new memory was created the function will return 1
 368  * to indicate to the calling function that the memory need to be freed
 369  * when not needed any more. The size will contain the new length of the
 370  * command.
 371  * If memory has not been allocated we rely on the original mechanisms to
 372  * free the memory of the command - even when we reduce the value of size.
 373  */
 374 static
 375 int hwarc_filter_cmd_WUSB_0100(struct uwb_rc *rc, struct uwb_rccb **header,
 376                                size_t *size)
 377 {
 378         int result;
 379         struct uwb_rccb *rccb = *header;
 380         int cmd = le16_to_cpu(rccb->wCommand);
 381         switch (cmd) {
 382         case UWB_RC_CMD_SCAN:
 383                 result = hwarc_filter_cmd_scan_WUSB_0100(rc, header, size);
 384                 break;
 385         case UWB_RC_CMD_SET_DRP_IE:
 386                 result = hwarc_filter_cmd_set_drp_ie_WUSB_0100(rc, header, size);
 387                 break;
 388         default:
 389                 result = -ENOANO;
 390                 break;
 391         }
 392         return result;
 393 }
 394 
 395 
 396 /**
 397  * Filter data from WHCI driver to WUSB device
 398  *
 399  * @header: WHCI 0.95 compliant command from driver
 400  * @size:   length of command
 401  *
 402  * Filter commands based on which protocol the device supports. The WUSB
 403  * errata should be the same as WHCI 0.95 so we do not filter that here -
 404  * only WUSB 1.0.
 405  */
 406 static
 407 int hwarc_filter_cmd(struct uwb_rc *rc, struct uwb_rccb **header,
 408                      size_t *size)
 409 {
 410         int result = -ENOANO;
 411         if (rc->version == 0x0100)
 412                 result = hwarc_filter_cmd_WUSB_0100(rc, header, size);
 413         return result;
 414 }
 415 
 416 
 417 /**
 418  * Compute return value as sum of incoming value and value at given offset
 419  *
 420  * @rceb:      event for which we compute the size, it contains a variable
 421  *             length field.
 422  * @core_size: size of the "non variable" part of the event
 423  * @offset:    place in event where the length of the variable part is stored
 424  * @buf_size: total length of buffer in which event arrived - we need to make
 425  *             sure we read the offset in memory that is still part of the event
 426  */
 427 static
 428 ssize_t hwarc_get_event_size(struct uwb_rc *rc, const struct uwb_rceb *rceb,
 429                              size_t core_size, size_t offset,
 430                              const size_t buf_size)
 431 {
 432         ssize_t size = -ENOSPC;
 433         const void *ptr = rceb;
 434         size_t type_size = sizeof(__le16);
 435         struct device *dev = &rc->uwb_dev.dev;
 436 
 437         if (offset + type_size >= buf_size) {
 438                 dev_err(dev, "Not enough data to read extra size of event "
 439                         "0x%02x/%04x/%02x, only got %zu bytes.\n",
 440                         rceb->bEventType, le16_to_cpu(rceb->wEvent),
 441                         rceb->bEventContext, buf_size);
 442                 goto out;
 443         }
 444         ptr += offset;
 445         size = core_size + le16_to_cpu(*(__le16 *)ptr);
 446 out:
 447         return size;
 448 }
 449 
 450 
 451 /* Beacon slot change notification (WUSB 1.0 [8.6.3.5]) */
 452 struct uwb_rc_evt_bp_slot_change_WUSB_0100 {
 453         struct uwb_rceb rceb;
 454         u8 bSlotNumber;
 455 } __attribute__((packed));
 456 
 457 
 458 /**
 459  * Filter data from WUSB device to WHCI driver
 460  *
 461  * @header:      incoming event
 462  * @buf_size:    size of buffer in which event arrived
 463  * @_event_size: actual size of event in the buffer
 464  * @new_size:    size of event after filtered
 465  *
 466  * We don't know how the buffer is constructed - there may be more than one
 467  * event in it so buffer length does not determine event length. We first
 468  * determine the expected size of the incoming event. This value is passed
 469  * back only if the actual filtering succeeded (so we know the computed
 470  * expected size is correct). This value will be zero if
 471  * the event did not need any filtering.
 472  *
 473  * WHCI interprets the BP Slot Change event's data differently than
 474  * WUSB. The event sizes are exactly the same. The data field
 475  * indicates the new beacon slot in which a RC is transmitting its
 476  * beacon. The maximum value of this is 96 (wMacBPLength ECMA-368
 477  * 17.16 (Table 117)). We thus know that the WUSB value will not set
 478  * the bit bNoSlot, so we don't really do anything (placeholder).
 479  */
 480 static
 481 int hwarc_filter_event_WUSB_0100(struct uwb_rc *rc, struct uwb_rceb **header,
 482                                  const size_t buf_size, size_t *_real_size,
 483                                  size_t *_new_size)
 484 {
 485         int result = -ENOANO;
 486         struct uwb_rceb *rceb = *header;
 487         int event = le16_to_cpu(rceb->wEvent);
 488         ssize_t event_size;
 489         size_t core_size, offset;
 490 
 491         if (rceb->bEventType != UWB_RC_CET_GENERAL)
 492                 goto out;
 493         switch (event) {
 494         case UWB_RC_EVT_BEACON:
 495                 core_size = sizeof(struct uwb_rc_evt_beacon_WUSB_0100);
 496                 offset = offsetof(struct uwb_rc_evt_beacon_WUSB_0100,
 497                                   wBeaconInfoLength);
 498                 event_size = hwarc_get_event_size(rc, rceb, core_size,
 499                                                   offset, buf_size);
 500                 if (event_size < 0)
 501                         goto out;
 502                 *_real_size = event_size;
 503                 result = hwarc_filter_evt_beacon_WUSB_0100(rc, header,
 504                                                            buf_size, _new_size);
 505                 break;
 506         case UWB_RC_EVT_BP_SLOT_CHANGE:
 507                 *_new_size = *_real_size =
 508                         sizeof(struct uwb_rc_evt_bp_slot_change_WUSB_0100);
 509                 result = 0;
 510                 break;
 511 
 512         case UWB_RC_EVT_DRP_AVAIL:
 513                 core_size = sizeof(struct uwb_rc_evt_drp_avail_WUSB_0100);
 514                 offset = offsetof(struct uwb_rc_evt_drp_avail_WUSB_0100,
 515                                   wIELength);
 516                 event_size = hwarc_get_event_size(rc, rceb, core_size,
 517                                                   offset, buf_size);
 518                 if (event_size < 0)
 519                         goto out;
 520                 *_real_size = event_size;
 521                 result = hwarc_filter_evt_drp_avail_WUSB_0100(
 522                         rc, header, buf_size, _new_size);
 523                 break;
 524 
 525         case UWB_RC_EVT_DRP:
 526                 core_size = sizeof(struct uwb_rc_evt_drp_WUSB_0100);
 527                 offset = offsetof(struct uwb_rc_evt_drp_WUSB_0100, wIELength);
 528                 event_size = hwarc_get_event_size(rc, rceb, core_size,
 529                                                   offset, buf_size);
 530                 if (event_size < 0)
 531                         goto out;
 532                 *_real_size = event_size;
 533                 result = hwarc_filter_evt_drp_WUSB_0100(rc, header,
 534                                                         buf_size, _new_size);
 535                 break;
 536 
 537         default:
 538                 break;
 539         }
 540 out:
 541         return result;
 542 }
 543 
 544 /**
 545  * Filter data from WUSB device to WHCI driver
 546  *
 547  * @header:      incoming event
 548  * @buf_size:    size of buffer in which event arrived
 549  * @_event_size: actual size of event in the buffer
 550  * @_new_size:   size of event after filtered
 551  *
 552  * Filter events based on which protocol the device supports. The WUSB
 553  * errata should be the same as WHCI 0.95 so we do not filter that here -
 554  * only WUSB 1.0.
 555  *
 556  * If we don't handle it, we return -ENOANO (why the weird error code?
 557  * well, so if I get it, I can pinpoint in the code that raised
 558  * it...after all, not too many places use the higher error codes).
 559  */
 560 static
 561 int hwarc_filter_event(struct uwb_rc *rc, struct uwb_rceb **header,
 562                        const size_t buf_size, size_t *_real_size,
 563                        size_t *_new_size)
 564 {
 565         int result = -ENOANO;
 566         if (rc->version == 0x0100)
 567                 result =  hwarc_filter_event_WUSB_0100(
 568                         rc, header, buf_size, _real_size, _new_size);
 569         return result;
 570 }
 571 
 572 
 573 /**
 574  * Execute an UWB RC command on HWA
 575  *
 576  * @rc:       Instance of a Radio Controller that is a HWA
 577  * @cmd:      Buffer containing the RCCB and payload to execute
 578  * @cmd_size: Size of the command buffer.
 579  *
 580  * NOTE: rc's mutex has to be locked
 581  */
 582 static
 583 int hwarc_cmd(struct uwb_rc *uwb_rc, const struct uwb_rccb *cmd, size_t cmd_size)
 584 {
 585         struct hwarc *hwarc = uwb_rc->priv;
 586         return usb_control_msg(
 587                 hwarc->usb_dev, usb_sndctrlpipe(hwarc->usb_dev, 0),
 588                 WA_EXEC_RC_CMD, USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 589                 0, hwarc->usb_iface->cur_altsetting->desc.bInterfaceNumber,
 590                 (void *) cmd, cmd_size, 100 /* FIXME: this is totally arbitrary */);
 591 }
 592 
 593 static
 594 int hwarc_reset(struct uwb_rc *uwb_rc)
 595 {
 596         struct hwarc *hwarc = uwb_rc->priv;
 597         int result;
 598 
 599         /* device lock must be held when calling usb_reset_device. */
 600         result = usb_lock_device_for_reset(hwarc->usb_dev, NULL);
 601         if (result >= 0) {
 602                 result = usb_reset_device(hwarc->usb_dev);
 603                 usb_unlock_device(hwarc->usb_dev);
 604         }
 605 
 606         return result;
 607 }
 608 
 609 /**
 610  * Callback for the notification and event endpoint
 611  *
 612  * Check's that everything is fine and then passes the read data to
 613  * the notification/event handling mechanism (neh).
 614  */
 615 static
 616 void hwarc_neep_cb(struct urb *urb)
 617 {
 618         struct hwarc *hwarc = urb->context;
 619         struct usb_interface *usb_iface = hwarc->usb_iface;
 620         struct device *dev = &usb_iface->dev;
 621         int result;
 622 
 623         switch (result = urb->status) {
 624         case 0:
 625                 uwb_rc_neh_grok(hwarc->uwb_rc, urb->transfer_buffer,
 626                                 urb->actual_length);
 627                 break;
 628         case -ECONNRESET:       /* Not an error, but a controlled situation; */
 629         case -ENOENT:           /* (we killed the URB)...so, no broadcast */
 630                 goto out;
 631         case -ESHUTDOWN:        /* going away! */
 632                 goto out;
 633         default:                /* On general errors, retry unless it gets ugly */
 634                 if (edc_inc(&hwarc->neep_edc, EDC_MAX_ERRORS,
 635                             EDC_ERROR_TIMEFRAME))
 636                         goto error_exceeded;
 637                 dev_err(dev, "NEEP: URB error %d\n", urb->status);
 638         }
 639         result = usb_submit_urb(urb, GFP_ATOMIC);
 640         if (result < 0 && result != -ENODEV && result != -EPERM) {
 641                 /* ignoring unrecoverable errors */
 642                 dev_err(dev, "NEEP: Can't resubmit URB (%d) resetting device\n",
 643                         result);
 644                 goto error;
 645         }
 646 out:
 647         return;
 648 
 649 error_exceeded:
 650         dev_err(dev, "NEEP: URB max acceptable errors "
 651                 "exceeded, resetting device\n");
 652 error:
 653         uwb_rc_neh_error(hwarc->uwb_rc, result);
 654         uwb_rc_reset_all(hwarc->uwb_rc);
 655         return;
 656 }
 657 
 658 static void hwarc_init(struct hwarc *hwarc)
 659 {
 660         edc_init(&hwarc->neep_edc);
 661 }
 662 
 663 /**
 664  * Initialize the notification/event endpoint stuff
 665  *
 666  * Note this is effectively a parallel thread; it knows that
 667  * hwarc->uwb_rc always exists because the existence of a 'hwarc'
 668  * means that there is a reverence on the hwarc->uwb_rc (see
 669  * _probe()), and thus _neep_cb() can execute safely.
 670  */
 671 static int hwarc_neep_init(struct uwb_rc *rc)
 672 {
 673         struct hwarc *hwarc = rc->priv;
 674         struct usb_interface *iface = hwarc->usb_iface;
 675         struct usb_device *usb_dev = interface_to_usbdev(iface);
 676         struct device *dev = &iface->dev;
 677         int result;
 678         struct usb_endpoint_descriptor *epd;
 679 
 680         epd = &iface->cur_altsetting->endpoint[0].desc;
 681         hwarc->rd_buffer = (void *) __get_free_page(GFP_KERNEL);
 682         if (hwarc->rd_buffer == NULL) {
 683                 dev_err(dev, "Unable to allocate notification's read buffer\n");
 684                 goto error_rd_buffer;
 685         }
 686         hwarc->neep_urb = usb_alloc_urb(0, GFP_KERNEL);
 687         if (hwarc->neep_urb == NULL)
 688                 goto error_urb_alloc;
 689         usb_fill_int_urb(hwarc->neep_urb, usb_dev,
 690                          usb_rcvintpipe(usb_dev, epd->bEndpointAddress),
 691                          hwarc->rd_buffer, PAGE_SIZE,
 692                          hwarc_neep_cb, hwarc, epd->bInterval);
 693         result = usb_submit_urb(hwarc->neep_urb, GFP_ATOMIC);
 694         if (result < 0) {
 695                 dev_err(dev, "Cannot submit notification URB: %d\n", result);
 696                 goto error_neep_submit;
 697         }
 698         return 0;
 699 
 700 error_neep_submit:
 701         usb_free_urb(hwarc->neep_urb);
 702         hwarc->neep_urb = NULL;
 703 error_urb_alloc:
 704         free_page((unsigned long)hwarc->rd_buffer);
 705         hwarc->rd_buffer = NULL;
 706 error_rd_buffer:
 707         return -ENOMEM;
 708 }
 709 
 710 
 711 /** Clean up all the notification endpoint resources */
 712 static void hwarc_neep_release(struct uwb_rc *rc)
 713 {
 714         struct hwarc *hwarc = rc->priv;
 715 
 716         usb_kill_urb(hwarc->neep_urb);
 717         usb_free_urb(hwarc->neep_urb);
 718         hwarc->neep_urb = NULL;
 719 
 720         free_page((unsigned long)hwarc->rd_buffer);
 721         hwarc->rd_buffer = NULL;
 722 }
 723 
 724 /**
 725  * Get the version from class-specific descriptor
 726  *
 727  * NOTE: this descriptor comes with the big bundled configuration
 728  *       descriptor that includes the interfaces' and endpoints', so
 729  *       we just look for it in the cached copy kept by the USB stack.
 730  *
 731  * NOTE2: We convert LE fields to CPU order.
 732  */
 733 static int hwarc_get_version(struct uwb_rc *rc)
 734 {
 735         int result;
 736 
 737         struct hwarc *hwarc = rc->priv;
 738         struct uwb_rc_control_intf_class_desc *descr;
 739         struct device *dev = &rc->uwb_dev.dev;
 740         struct usb_device *usb_dev = hwarc->usb_dev;
 741         char *itr;
 742         struct usb_descriptor_header *hdr;
 743         size_t itr_size, actconfig_idx;
 744         u16 version;
 745 
 746         actconfig_idx = (usb_dev->actconfig - usb_dev->config) /
 747                 sizeof(usb_dev->config[0]);
 748         itr = usb_dev->rawdescriptors[actconfig_idx];
 749         itr_size = le16_to_cpu(usb_dev->actconfig->desc.wTotalLength);
 750         while (itr_size >= sizeof(*hdr)) {
 751                 hdr = (struct usb_descriptor_header *) itr;
 752                 dev_dbg(dev, "Extra device descriptor: "
 753                         "type %02x/%u bytes @ %zu (%zu left)\n",
 754                         hdr->bDescriptorType, hdr->bLength,
 755                         (itr - usb_dev->rawdescriptors[actconfig_idx]),
 756                         itr_size);
 757                 if (hdr->bDescriptorType == USB_DT_CS_RADIO_CONTROL)
 758                         goto found;
 759                 itr += hdr->bLength;
 760                 itr_size -= hdr->bLength;
 761         }
 762         dev_err(dev, "cannot find Radio Control Interface Class descriptor\n");
 763         return -ENODEV;
 764 
 765 found:
 766         result = -EINVAL;
 767         if (hdr->bLength > itr_size) {  /* is it available? */
 768                 dev_err(dev, "incomplete Radio Control Interface Class "
 769                         "descriptor (%zu bytes left, %u needed)\n",
 770                         itr_size, hdr->bLength);
 771                 goto error;
 772         }
 773         if (hdr->bLength < sizeof(*descr)) {
 774                 dev_err(dev, "short Radio Control Interface Class "
 775                         "descriptor\n");
 776                 goto error;
 777         }
 778         descr = (struct uwb_rc_control_intf_class_desc *) hdr;
 779         /* Make LE fields CPU order */
 780         version = __le16_to_cpu(descr->bcdRCIVersion);
 781         if (version != 0x0100) {
 782                 dev_err(dev, "Device reports protocol version 0x%04x. We "
 783                         "do not support that. \n", version);
 784                 result = -EINVAL;
 785                 goto error;
 786         }
 787         rc->version = version;
 788         dev_dbg(dev, "Device supports WUSB protocol version 0x%04x \n", rc->version);
 789         result = 0;
 790 error:
 791         return result;
 792 }
 793 
 794 /*
 795  * By creating a 'uwb_rc', we have a reference on it -- that reference
 796  * is the one we drop when we disconnect.
 797  *
 798  * No need to switch altsettings; according to WUSB1.0[8.6.1.1], there
 799  * is only one altsetting allowed.
 800  */
 801 static int hwarc_probe(struct usb_interface *iface,
 802                        const struct usb_device_id *id)
 803 {
 804         int result;
 805         struct uwb_rc *uwb_rc;
 806         struct hwarc *hwarc;
 807         struct device *dev = &iface->dev;
 808 
 809         if (iface->cur_altsetting->desc.bNumEndpoints < 1)
 810                 return -ENODEV;
 811         if (!usb_endpoint_xfer_int(&iface->cur_altsetting->endpoint[0].desc))
 812                 return -ENODEV;
 813 
 814         result = -ENOMEM;
 815         uwb_rc = uwb_rc_alloc();
 816         if (uwb_rc == NULL) {
 817                 dev_err(dev, "unable to allocate RC instance\n");
 818                 goto error_rc_alloc;
 819         }
 820         hwarc = kzalloc(sizeof(*hwarc), GFP_KERNEL);
 821         if (hwarc == NULL) {
 822                 dev_err(dev, "unable to allocate HWA RC instance\n");
 823                 goto error_alloc;
 824         }
 825         hwarc_init(hwarc);
 826         hwarc->usb_dev = usb_get_dev(interface_to_usbdev(iface));
 827         hwarc->usb_iface = usb_get_intf(iface);
 828         hwarc->uwb_rc = uwb_rc;
 829 
 830         uwb_rc->owner = THIS_MODULE;
 831         uwb_rc->start = hwarc_neep_init;
 832         uwb_rc->stop  = hwarc_neep_release;
 833         uwb_rc->cmd   = hwarc_cmd;
 834         uwb_rc->reset = hwarc_reset;
 835         if (id->driver_info & WUSB_QUIRK_WHCI_CMD_EVT) {
 836                 uwb_rc->filter_cmd   = NULL;
 837                 uwb_rc->filter_event = NULL;
 838         } else {
 839                 uwb_rc->filter_cmd   = hwarc_filter_cmd;
 840                 uwb_rc->filter_event = hwarc_filter_event;
 841         }
 842 
 843         result = uwb_rc_add(uwb_rc, dev, hwarc);
 844         if (result < 0)
 845                 goto error_rc_add;
 846         result = hwarc_get_version(uwb_rc);
 847         if (result < 0) {
 848                 dev_err(dev, "cannot retrieve version of RC \n");
 849                 goto error_get_version;
 850         }
 851         usb_set_intfdata(iface, hwarc);
 852         return 0;
 853 
 854 error_get_version:
 855         uwb_rc_rm(uwb_rc);
 856 error_rc_add:
 857         usb_put_intf(iface);
 858         usb_put_dev(hwarc->usb_dev);
 859         kfree(hwarc);
 860 error_alloc:
 861         uwb_rc_put(uwb_rc);
 862 error_rc_alloc:
 863         return result;
 864 }
 865 
 866 static void hwarc_disconnect(struct usb_interface *iface)
 867 {
 868         struct hwarc *hwarc = usb_get_intfdata(iface);
 869         struct uwb_rc *uwb_rc = hwarc->uwb_rc;
 870 
 871         usb_set_intfdata(hwarc->usb_iface, NULL);
 872         uwb_rc_rm(uwb_rc);
 873         usb_put_intf(hwarc->usb_iface);
 874         usb_put_dev(hwarc->usb_dev);
 875         kfree(hwarc);
 876         uwb_rc_put(uwb_rc);     /* when creating the device, refcount = 1 */
 877 }
 878 
 879 static int hwarc_pre_reset(struct usb_interface *iface)
 880 {
 881         struct hwarc *hwarc = usb_get_intfdata(iface);
 882         struct uwb_rc *uwb_rc = hwarc->uwb_rc;
 883 
 884         uwb_rc_pre_reset(uwb_rc);
 885         return 0;
 886 }
 887 
 888 static int hwarc_post_reset(struct usb_interface *iface)
 889 {
 890         struct hwarc *hwarc = usb_get_intfdata(iface);
 891         struct uwb_rc *uwb_rc = hwarc->uwb_rc;
 892 
 893         return uwb_rc_post_reset(uwb_rc);
 894 }
 895 
 896 /** USB device ID's that we handle */
 897 static const struct usb_device_id hwarc_id_table[] = {
 898         /* D-Link DUB-1210 */
 899         { USB_DEVICE_AND_INTERFACE_INFO(0x07d1, 0x3d02, 0xe0, 0x01, 0x02),
 900           .driver_info = WUSB_QUIRK_WHCI_CMD_EVT },
 901         /* Intel i1480 (using firmware 1.3PA2-20070828) */
 902         { USB_DEVICE_AND_INTERFACE_INFO(0x8086, 0x0c3b, 0xe0, 0x01, 0x02),
 903           .driver_info = WUSB_QUIRK_WHCI_CMD_EVT },
 904         /* Alereon 5310 */
 905         { USB_DEVICE_AND_INTERFACE_INFO(0x13dc, 0x5310, 0xe0, 0x01, 0x02),
 906           .driver_info = WUSB_QUIRK_WHCI_CMD_EVT },
 907         /* Alereon 5611 */
 908         { USB_DEVICE_AND_INTERFACE_INFO(0x13dc, 0x5611, 0xe0, 0x01, 0x02),
 909           .driver_info = WUSB_QUIRK_WHCI_CMD_EVT },
 910         /* Generic match for the Radio Control interface */
 911         { USB_INTERFACE_INFO(0xe0, 0x01, 0x02), },
 912         { },
 913 };
 914 MODULE_DEVICE_TABLE(usb, hwarc_id_table);
 915 
 916 static struct usb_driver hwarc_driver = {
 917         .name =         "hwa-rc",
 918         .id_table =     hwarc_id_table,
 919         .probe =        hwarc_probe,
 920         .disconnect =   hwarc_disconnect,
 921         .pre_reset =    hwarc_pre_reset,
 922         .post_reset =   hwarc_post_reset,
 923 };
 924 
 925 module_usb_driver(hwarc_driver);
 926 
 927 MODULE_AUTHOR("Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>");
 928 MODULE_DESCRIPTION("Host Wireless Adapter Radio Control Driver");
 929 MODULE_LICENSE("GPL");