1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Wireless USB Host Controller
4 * Root Hub operations
5 *
6 *
7 * Copyright (C) 2005-2006 Intel Corporation
8 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
9 *
10 * We fake a root hub that has fake ports (as many as simultaneous
11 * devices the Wireless USB Host Controller can deal with). For each
12 * port we keep an state in @wusbhc->port[index] identical to the one
13 * specified in the USB2.0[ch11] spec and some extra device
14 * information that complements the one in 'struct usb_device' (as
15 * this lacs a hcpriv pointer).
16 *
17 * Note this is common to WHCI and HWA host controllers.
18 *
19 * Through here we enable most of the state changes that the USB stack
20 * will use to connect or disconnect devices. We need to do some
21 * forced adaptation of Wireless USB device states vs. wired:
22 *
23 * USB: WUSB:
24 *
25 * Port Powered-off port slot n/a
26 * Powered-on port slot available
27 * Disconnected port slot available
28 * Connected port slot assigned device
29 * device sent DN_Connect
30 * device was authenticated
31 * Enabled device is authenticated, transitioned
32 * from unauth -> auth -> default address
33 * -> enabled
34 * Reset disconnect
35 * Disable disconnect
36 *
37 * This maps the standard USB port states with the WUSB device states
38 * so we can fake ports without having to modify the USB stack.
39 *
40 * FIXME: this process will change in the future
41 *
42 *
43 * ENTRY POINTS
44 *
45 * Our entry points into here are, as in hcd.c, the USB stack root hub
46 * ops defined in the usb_hcd struct:
47 *
48 * wusbhc_rh_status_data() Provide hub and port status data bitmap
49 *
50 * wusbhc_rh_control() Execution of all the major requests
51 * you can do to a hub (Set|Clear
52 * features, get descriptors, status, etc).
53 *
54 * wusbhc_rh_[suspend|resume]() That
55 *
56 * wusbhc_rh_start_port_reset() ??? unimplemented
57 */
58 #include <linux/slab.h>
59 #include <linux/export.h>
60 #include "wusbhc.h"
61
62 /*
63 * Reset a fake port
64 *
65 * Using a Reset Device IE is too heavyweight as it causes the device
66 * to enter the UnConnected state and leave the cluster, this can mean
67 * that when the device reconnects it is connected to a different fake
68 * port.
69 *
70 * Instead, reset authenticated devices with a SetAddress(0), followed
71 * by a SetAddresss(AuthAddr).
72 *
73 * For unauthenticated devices just pretend to reset but do nothing.
74 * If the device initialization continues to fail it will eventually
75 * time out after TrustTimeout and enter the UnConnected state.
76 *
77 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
78 *
79 * Supposedly we are the only thread accesing @wusbhc->port; in any
80 * case, maybe we should move the mutex locking from
81 * wusbhc_devconnect_auth() to here.
82 *
83 * @port_idx refers to the wusbhc's port index, not the USB port number
84 */
85 static int wusbhc_rh_port_reset(struct wusbhc *wusbhc, u8 port_idx)
86 {
87 int result = 0;
88 struct wusb_port *port = wusb_port_by_idx(wusbhc, port_idx);
89 struct wusb_dev *wusb_dev = port->wusb_dev;
90
91 if (wusb_dev == NULL)
92 return -ENOTCONN;
93
94 port->status |= USB_PORT_STAT_RESET;
95 port->change |= USB_PORT_STAT_C_RESET;
96
97 if (wusb_dev->addr & WUSB_DEV_ADDR_UNAUTH)
98 result = 0;
99 else
100 result = wusb_dev_update_address(wusbhc, wusb_dev);
101
102 port->status &= ~USB_PORT_STAT_RESET;
103 port->status |= USB_PORT_STAT_ENABLE;
104 port->change |= USB_PORT_STAT_C_RESET | USB_PORT_STAT_C_ENABLE;
105
106 return result;
107 }
108
109 /*
110 * Return the hub change status bitmap
111 *
112 * The bits in the change status bitmap are cleared when a
113 * ClearPortFeature request is issued (USB2.0[11.12.3,11.12.4].
114 *
115 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
116 *
117 * WARNING!! This gets called from atomic context; we cannot get the
118 * mutex--the only race condition we can find is some bit
119 * changing just after we copy it, which shouldn't be too
120 * big of a problem [and we can't make it an spinlock
121 * because other parts need to take it and sleep] .
122 *
123 * @usb_hcd is refcounted, so it won't disappear under us
124 * and before killing a host, the polling of the root hub
125 * would be stopped anyway.
126 */
127 int wusbhc_rh_status_data(struct usb_hcd *usb_hcd, char *_buf)
128 {
129 struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
130 size_t cnt, size, bits_set = 0;
131
132 /* WE DON'T LOCK, see comment */
133 /* round up to bytes. Hub bit is bit 0 so add 1. */
134 size = DIV_ROUND_UP(wusbhc->ports_max + 1, 8);
135
136 /* clear the output buffer. */
137 memset(_buf, 0, size);
138 /* set the bit for each changed port. */
139 for (cnt = 0; cnt < wusbhc->ports_max; cnt++) {
140
141 if (wusb_port_by_idx(wusbhc, cnt)->change) {
142 const int bitpos = cnt+1;
143
144 _buf[bitpos/8] |= (1 << (bitpos % 8));
145 bits_set++;
146 }
147 }
148
149 return bits_set ? size : 0;
150 }
151 EXPORT_SYMBOL_GPL(wusbhc_rh_status_data);
152
153 /*
154 * Return the hub's descriptor
155 *
156 * NOTE: almost cut and paste from ehci-hub.c
157 *
158 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked
159 */
160 static int wusbhc_rh_get_hub_descr(struct wusbhc *wusbhc, u16 wValue,
161 u16 wIndex,
162 struct usb_hub_descriptor *descr,
163 u16 wLength)
164 {
165 u16 temp = 1 + (wusbhc->ports_max / 8);
166 u8 length = 7 + 2 * temp;
167
168 if (wLength < length)
169 return -ENOSPC;
170 descr->bDescLength = 7 + 2 * temp;
171 descr->bDescriptorType = USB_DT_HUB; /* HUB type */
172 descr->bNbrPorts = wusbhc->ports_max;
173 descr->wHubCharacteristics = cpu_to_le16(
174 HUB_CHAR_COMMON_LPSM /* All ports power at once */
175 | 0x00 /* not part of compound device */
176 | HUB_CHAR_NO_OCPM /* No overcurrent protection */
177 | 0x00 /* 8 FS think time FIXME ?? */
178 | 0x00); /* No port indicators */
179 descr->bPwrOn2PwrGood = 0;
180 descr->bHubContrCurrent = 0;
181 /* two bitmaps: ports removable, and usb 1.0 legacy PortPwrCtrlMask */
182 memset(&descr->u.hs.DeviceRemovable[0], 0, temp);
183 memset(&descr->u.hs.DeviceRemovable[temp], 0xff, temp);
184 return 0;
185 }
186
187 /*
188 * Clear a hub feature
189 *
190 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
191 *
192 * Nothing to do, so no locking needed ;)
193 */
194 static int wusbhc_rh_clear_hub_feat(struct wusbhc *wusbhc, u16 feature)
195 {
196 int result;
197
198 switch (feature) {
199 case C_HUB_LOCAL_POWER:
200 /* FIXME: maybe plug bit 0 to the power input status,
201 * if any?
202 * see wusbhc_rh_get_hub_status() */
203 case C_HUB_OVER_CURRENT:
204 result = 0;
205 break;
206 default:
207 result = -EPIPE;
208 }
209 return result;
210 }
211
212 /*
213 * Return hub status (it is always zero...)
214 *
215 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
216 *
217 * Nothing to do, so no locking needed ;)
218 */
219 static int wusbhc_rh_get_hub_status(struct wusbhc *wusbhc, u32 *buf,
220 u16 wLength)
221 {
222 /* FIXME: maybe plug bit 0 to the power input status (if any)? */
223 *buf = 0;
224 return 0;
225 }
226
227 /*
228 * Set a port feature
229 *
230 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
231 */
232 static int wusbhc_rh_set_port_feat(struct wusbhc *wusbhc, u16 feature,
233 u8 selector, u8 port_idx)
234 {
235 struct device *dev = wusbhc->dev;
236
237 if (port_idx > wusbhc->ports_max)
238 return -EINVAL;
239
240 switch (feature) {
241 /* According to USB2.0[11.24.2.13]p2, these features
242 * are not required to be implemented. */
243 case USB_PORT_FEAT_C_OVER_CURRENT:
244 case USB_PORT_FEAT_C_ENABLE:
245 case USB_PORT_FEAT_C_SUSPEND:
246 case USB_PORT_FEAT_C_CONNECTION:
247 case USB_PORT_FEAT_C_RESET:
248 return 0;
249 case USB_PORT_FEAT_POWER:
250 /* No such thing, but we fake it works */
251 mutex_lock(&wusbhc->mutex);
252 wusb_port_by_idx(wusbhc, port_idx)->status |= USB_PORT_STAT_POWER;
253 mutex_unlock(&wusbhc->mutex);
254 return 0;
255 case USB_PORT_FEAT_RESET:
256 return wusbhc_rh_port_reset(wusbhc, port_idx);
257 case USB_PORT_FEAT_ENABLE:
258 case USB_PORT_FEAT_SUSPEND:
259 dev_err(dev, "(port_idx %d) set feat %d/%d UNIMPLEMENTED\n",
260 port_idx, feature, selector);
261 return -ENOSYS;
262 default:
263 dev_err(dev, "(port_idx %d) set feat %d/%d UNKNOWN\n",
264 port_idx, feature, selector);
265 return -EPIPE;
266 }
267
268 return 0;
269 }
270
271 /*
272 * Clear a port feature...
273 *
274 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
275 */
276 static int wusbhc_rh_clear_port_feat(struct wusbhc *wusbhc, u16 feature,
277 u8 selector, u8 port_idx)
278 {
279 int result = 0;
280 struct device *dev = wusbhc->dev;
281
282 if (port_idx > wusbhc->ports_max)
283 return -EINVAL;
284
285 mutex_lock(&wusbhc->mutex);
286 switch (feature) {
287 case USB_PORT_FEAT_POWER: /* fake port always on */
288 /* According to USB2.0[11.24.2.7.1.4], no need to implement? */
289 case USB_PORT_FEAT_C_OVER_CURRENT:
290 break;
291 case USB_PORT_FEAT_C_RESET:
292 wusb_port_by_idx(wusbhc, port_idx)->change &= ~USB_PORT_STAT_C_RESET;
293 break;
294 case USB_PORT_FEAT_C_CONNECTION:
295 wusb_port_by_idx(wusbhc, port_idx)->change &= ~USB_PORT_STAT_C_CONNECTION;
296 break;
297 case USB_PORT_FEAT_ENABLE:
298 __wusbhc_dev_disable(wusbhc, port_idx);
299 break;
300 case USB_PORT_FEAT_C_ENABLE:
301 wusb_port_by_idx(wusbhc, port_idx)->change &= ~USB_PORT_STAT_C_ENABLE;
302 break;
303 case USB_PORT_FEAT_SUSPEND:
304 case USB_PORT_FEAT_C_SUSPEND:
305 dev_err(dev, "(port_idx %d) Clear feat %d/%d UNIMPLEMENTED\n",
306 port_idx, feature, selector);
307 result = -ENOSYS;
308 break;
309 default:
310 dev_err(dev, "(port_idx %d) Clear feat %d/%d UNKNOWN\n",
311 port_idx, feature, selector);
312 result = -EPIPE;
313 break;
314 }
315 mutex_unlock(&wusbhc->mutex);
316
317 return result;
318 }
319
320 /*
321 * Return the port's status
322 *
323 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
324 */
325 static int wusbhc_rh_get_port_status(struct wusbhc *wusbhc, u16 port_idx,
326 u32 *_buf, u16 wLength)
327 {
328 __le16 *buf = (__le16 *)_buf;
329
330 if (port_idx > wusbhc->ports_max)
331 return -EINVAL;
332
333 mutex_lock(&wusbhc->mutex);
334 buf[0] = cpu_to_le16(wusb_port_by_idx(wusbhc, port_idx)->status);
335 buf[1] = cpu_to_le16(wusb_port_by_idx(wusbhc, port_idx)->change);
336 mutex_unlock(&wusbhc->mutex);
337
338 return 0;
339 }
340
341 /*
342 * Entry point for Root Hub operations
343 *
344 * @wusbhc is assumed referenced and @wusbhc->mutex unlocked.
345 */
346 int wusbhc_rh_control(struct usb_hcd *usb_hcd, u16 reqntype, u16 wValue,
347 u16 wIndex, char *buf, u16 wLength)
348 {
349 int result = -ENOSYS;
350 struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
351
352 switch (reqntype) {
353 case GetHubDescriptor:
354 result = wusbhc_rh_get_hub_descr(
355 wusbhc, wValue, wIndex,
356 (struct usb_hub_descriptor *) buf, wLength);
357 break;
358 case ClearHubFeature:
359 result = wusbhc_rh_clear_hub_feat(wusbhc, wValue);
360 break;
361 case GetHubStatus:
362 result = wusbhc_rh_get_hub_status(wusbhc, (u32 *)buf, wLength);
363 break;
364
365 case SetPortFeature:
366 result = wusbhc_rh_set_port_feat(wusbhc, wValue, wIndex >> 8,
367 (wIndex & 0xff) - 1);
368 break;
369 case ClearPortFeature:
370 result = wusbhc_rh_clear_port_feat(wusbhc, wValue, wIndex >> 8,
371 (wIndex & 0xff) - 1);
372 break;
373 case GetPortStatus:
374 result = wusbhc_rh_get_port_status(wusbhc, wIndex - 1,
375 (u32 *)buf, wLength);
376 break;
377
378 case SetHubFeature:
379 default:
380 dev_err(wusbhc->dev, "%s (%p [%p], %x, %x, %x, %p, %x) "
381 "UNIMPLEMENTED\n", __func__, usb_hcd, wusbhc, reqntype,
382 wValue, wIndex, buf, wLength);
383 /* dump_stack(); */
384 result = -ENOSYS;
385 }
386 return result;
387 }
388 EXPORT_SYMBOL_GPL(wusbhc_rh_control);
389
390 int wusbhc_rh_start_port_reset(struct usb_hcd *usb_hcd, unsigned port_idx)
391 {
392 struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
393 dev_err(wusbhc->dev, "%s (%p [%p], port_idx %u) UNIMPLEMENTED\n",
394 __func__, usb_hcd, wusbhc, port_idx);
395 WARN_ON(1);
396 return -ENOSYS;
397 }
398 EXPORT_SYMBOL_GPL(wusbhc_rh_start_port_reset);
399
400 static void wusb_port_init(struct wusb_port *port)
401 {
402 port->status |= USB_PORT_STAT_HIGH_SPEED;
403 }
404
405 /*
406 * Alloc fake port specific fields and status.
407 */
408 int wusbhc_rh_create(struct wusbhc *wusbhc)
409 {
410 int result = -ENOMEM;
411 size_t port_size, itr;
412 port_size = wusbhc->ports_max * sizeof(wusbhc->port[0]);
413 wusbhc->port = kzalloc(port_size, GFP_KERNEL);
414 if (wusbhc->port == NULL)
415 goto error_port_alloc;
416 for (itr = 0; itr < wusbhc->ports_max; itr++)
417 wusb_port_init(&wusbhc->port[itr]);
418 result = 0;
419 error_port_alloc:
420 return result;
421 }
422
423 void wusbhc_rh_destroy(struct wusbhc *wusbhc)
424 {
425 kfree(wusbhc->port);
426 }