1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * drivers/usb/core/driver.c - most of the driver model stuff for usb |
4 | * |
5 | * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de> |
6 | * |
7 | * based on drivers/usb/usb.c which had the following copyrights: |
8 | * (C) Copyright Linus Torvalds 1999 |
9 | * (C) Copyright Johannes Erdfelt 1999-2001 |
10 | * (C) Copyright Andreas Gal 1999 |
11 | * (C) Copyright Gregory P. Smith 1999 |
12 | * (C) Copyright Deti Fliegl 1999 (new USB architecture) |
13 | * (C) Copyright Randy Dunlap 2000 |
14 | * (C) Copyright David Brownell 2000-2004 |
15 | * (C) Copyright Yggdrasil Computing, Inc. 2000 |
16 | * (usb_device_id matching changes by Adam J. Richter) |
17 | * (C) Copyright Greg Kroah-Hartman 2002-2003 |
18 | * |
19 | * Released under the GPLv2 only. |
20 | * |
21 | * NOTE! This is not actually a driver at all, rather this is |
22 | * just a collection of helper routines that implement the |
23 | * matching, probing, releasing, suspending and resuming for |
24 | * real drivers. |
25 | * |
26 | */ |
27 | |
28 | #include <linux/device.h> |
29 | #include <linux/slab.h> |
30 | #include <linux/export.h> |
31 | #include <linux/usb.h> |
32 | #include <linux/usb/quirks.h> |
33 | #include <linux/usb/hcd.h> |
34 | |
35 | #include "usb.h" |
36 | |
37 | |
38 | /* |
39 | * Adds a new dynamic USBdevice ID to this driver, |
40 | * and cause the driver to probe for all devices again. |
41 | */ |
42 | ssize_t usb_store_new_id(struct usb_dynids *dynids, |
43 | const struct usb_device_id *id_table, |
44 | struct device_driver *driver, |
45 | const char *buf, size_t count) |
46 | { |
47 | struct usb_dynid *dynid; |
48 | u32 idVendor = 0; |
49 | u32 idProduct = 0; |
50 | unsigned int bInterfaceClass = 0; |
51 | u32 refVendor, refProduct; |
52 | int fields = 0; |
53 | int retval = 0; |
54 | |
55 | fields = sscanf(buf, "%x %x %x %x %x" , &idVendor, &idProduct, |
56 | &bInterfaceClass, &refVendor, &refProduct); |
57 | if (fields < 2) |
58 | return -EINVAL; |
59 | |
60 | dynid = kzalloc(size: sizeof(*dynid), GFP_KERNEL); |
61 | if (!dynid) |
62 | return -ENOMEM; |
63 | |
64 | INIT_LIST_HEAD(list: &dynid->node); |
65 | dynid->id.idVendor = idVendor; |
66 | dynid->id.idProduct = idProduct; |
67 | dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE; |
68 | if (fields > 2 && bInterfaceClass) { |
69 | if (bInterfaceClass > 255) { |
70 | retval = -EINVAL; |
71 | goto fail; |
72 | } |
73 | |
74 | dynid->id.bInterfaceClass = (u8)bInterfaceClass; |
75 | dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS; |
76 | } |
77 | |
78 | if (fields > 4) { |
79 | const struct usb_device_id *id = id_table; |
80 | |
81 | if (!id) { |
82 | retval = -ENODEV; |
83 | goto fail; |
84 | } |
85 | |
86 | for (; id->match_flags; id++) |
87 | if (id->idVendor == refVendor && id->idProduct == refProduct) |
88 | break; |
89 | |
90 | if (id->match_flags) { |
91 | dynid->id.driver_info = id->driver_info; |
92 | } else { |
93 | retval = -ENODEV; |
94 | goto fail; |
95 | } |
96 | } |
97 | |
98 | spin_lock(lock: &dynids->lock); |
99 | list_add_tail(new: &dynid->node, head: &dynids->list); |
100 | spin_unlock(lock: &dynids->lock); |
101 | |
102 | retval = driver_attach(drv: driver); |
103 | |
104 | if (retval) |
105 | return retval; |
106 | return count; |
107 | |
108 | fail: |
109 | kfree(objp: dynid); |
110 | return retval; |
111 | } |
112 | EXPORT_SYMBOL_GPL(usb_store_new_id); |
113 | |
114 | ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf) |
115 | { |
116 | struct usb_dynid *dynid; |
117 | size_t count = 0; |
118 | |
119 | list_for_each_entry(dynid, &dynids->list, node) |
120 | if (dynid->id.bInterfaceClass != 0) |
121 | count += scnprintf(buf: &buf[count], PAGE_SIZE - count, fmt: "%04x %04x %02x\n" , |
122 | dynid->id.idVendor, dynid->id.idProduct, |
123 | dynid->id.bInterfaceClass); |
124 | else |
125 | count += scnprintf(buf: &buf[count], PAGE_SIZE - count, fmt: "%04x %04x\n" , |
126 | dynid->id.idVendor, dynid->id.idProduct); |
127 | return count; |
128 | } |
129 | EXPORT_SYMBOL_GPL(usb_show_dynids); |
130 | |
131 | static ssize_t new_id_show(struct device_driver *driver, char *buf) |
132 | { |
133 | struct usb_driver *usb_drv = to_usb_driver(driver); |
134 | |
135 | return usb_show_dynids(&usb_drv->dynids, buf); |
136 | } |
137 | |
138 | static ssize_t new_id_store(struct device_driver *driver, |
139 | const char *buf, size_t count) |
140 | { |
141 | struct usb_driver *usb_drv = to_usb_driver(driver); |
142 | |
143 | return usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, driver, buf, count); |
144 | } |
145 | static DRIVER_ATTR_RW(new_id); |
146 | |
147 | /* |
148 | * Remove a USB device ID from this driver |
149 | */ |
150 | static ssize_t remove_id_store(struct device_driver *driver, const char *buf, |
151 | size_t count) |
152 | { |
153 | struct usb_dynid *dynid, *n; |
154 | struct usb_driver *usb_driver = to_usb_driver(driver); |
155 | u32 idVendor; |
156 | u32 idProduct; |
157 | int fields; |
158 | |
159 | fields = sscanf(buf, "%x %x" , &idVendor, &idProduct); |
160 | if (fields < 2) |
161 | return -EINVAL; |
162 | |
163 | spin_lock(lock: &usb_driver->dynids.lock); |
164 | list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) { |
165 | struct usb_device_id *id = &dynid->id; |
166 | |
167 | if ((id->idVendor == idVendor) && |
168 | (id->idProduct == idProduct)) { |
169 | list_del(entry: &dynid->node); |
170 | kfree(objp: dynid); |
171 | break; |
172 | } |
173 | } |
174 | spin_unlock(lock: &usb_driver->dynids.lock); |
175 | return count; |
176 | } |
177 | |
178 | static ssize_t remove_id_show(struct device_driver *driver, char *buf) |
179 | { |
180 | return new_id_show(driver, buf); |
181 | } |
182 | static DRIVER_ATTR_RW(remove_id); |
183 | |
184 | static int usb_create_newid_files(struct usb_driver *usb_drv) |
185 | { |
186 | int error = 0; |
187 | |
188 | if (usb_drv->no_dynamic_id) |
189 | goto exit; |
190 | |
191 | if (usb_drv->probe != NULL) { |
192 | error = driver_create_file(driver: &usb_drv->driver, |
193 | attr: &driver_attr_new_id); |
194 | if (error == 0) { |
195 | error = driver_create_file(driver: &usb_drv->driver, |
196 | attr: &driver_attr_remove_id); |
197 | if (error) |
198 | driver_remove_file(driver: &usb_drv->driver, |
199 | attr: &driver_attr_new_id); |
200 | } |
201 | } |
202 | exit: |
203 | return error; |
204 | } |
205 | |
206 | static void usb_remove_newid_files(struct usb_driver *usb_drv) |
207 | { |
208 | if (usb_drv->no_dynamic_id) |
209 | return; |
210 | |
211 | if (usb_drv->probe != NULL) { |
212 | driver_remove_file(driver: &usb_drv->driver, |
213 | attr: &driver_attr_remove_id); |
214 | driver_remove_file(driver: &usb_drv->driver, |
215 | attr: &driver_attr_new_id); |
216 | } |
217 | } |
218 | |
219 | static void usb_free_dynids(struct usb_driver *usb_drv) |
220 | { |
221 | struct usb_dynid *dynid, *n; |
222 | |
223 | spin_lock(lock: &usb_drv->dynids.lock); |
224 | list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) { |
225 | list_del(entry: &dynid->node); |
226 | kfree(objp: dynid); |
227 | } |
228 | spin_unlock(lock: &usb_drv->dynids.lock); |
229 | } |
230 | |
231 | static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf, |
232 | struct usb_driver *drv) |
233 | { |
234 | struct usb_dynid *dynid; |
235 | |
236 | spin_lock(lock: &drv->dynids.lock); |
237 | list_for_each_entry(dynid, &drv->dynids.list, node) { |
238 | if (usb_match_one_id(interface: intf, id: &dynid->id)) { |
239 | spin_unlock(lock: &drv->dynids.lock); |
240 | return &dynid->id; |
241 | } |
242 | } |
243 | spin_unlock(lock: &drv->dynids.lock); |
244 | return NULL; |
245 | } |
246 | |
247 | |
248 | /* called from driver core with dev locked */ |
249 | static int usb_probe_device(struct device *dev) |
250 | { |
251 | struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); |
252 | struct usb_device *udev = to_usb_device(dev); |
253 | int error = 0; |
254 | |
255 | dev_dbg(dev, "%s\n" , __func__); |
256 | |
257 | /* TODO: Add real matching code */ |
258 | |
259 | /* The device should always appear to be in use |
260 | * unless the driver supports autosuspend. |
261 | */ |
262 | if (!udriver->supports_autosuspend) |
263 | error = usb_autoresume_device(udev); |
264 | if (error) |
265 | return error; |
266 | |
267 | if (udriver->generic_subclass) |
268 | error = usb_generic_driver_probe(udev); |
269 | if (error) |
270 | return error; |
271 | |
272 | /* Probe the USB device with the driver in hand, but only |
273 | * defer to a generic driver in case the current USB |
274 | * device driver has an id_table or a match function; i.e., |
275 | * when the device driver was explicitly matched against |
276 | * a device. |
277 | * |
278 | * If the device driver does not have either of these, |
279 | * then we assume that it can bind to any device and is |
280 | * not truly a more specialized/non-generic driver, so a |
281 | * return value of -ENODEV should not force the device |
282 | * to be handled by the generic USB driver, as there |
283 | * can still be another, more specialized, device driver. |
284 | * |
285 | * This accommodates the usbip driver. |
286 | * |
287 | * TODO: What if, in the future, there are multiple |
288 | * specialized USB device drivers for a particular device? |
289 | * In such cases, there is a need to try all matching |
290 | * specialised device drivers prior to setting the |
291 | * use_generic_driver bit. |
292 | */ |
293 | if (udriver->probe) |
294 | error = udriver->probe(udev); |
295 | else if (!udriver->generic_subclass) |
296 | error = -EINVAL; |
297 | if (error == -ENODEV && udriver != &usb_generic_driver && |
298 | (udriver->id_table || udriver->match)) { |
299 | udev->use_generic_driver = 1; |
300 | return -EPROBE_DEFER; |
301 | } |
302 | return error; |
303 | } |
304 | |
305 | /* called from driver core with dev locked */ |
306 | static int usb_unbind_device(struct device *dev) |
307 | { |
308 | struct usb_device *udev = to_usb_device(dev); |
309 | struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); |
310 | |
311 | if (udriver->disconnect) |
312 | udriver->disconnect(udev); |
313 | if (udriver->generic_subclass) |
314 | usb_generic_driver_disconnect(udev); |
315 | if (!udriver->supports_autosuspend) |
316 | usb_autosuspend_device(udev); |
317 | return 0; |
318 | } |
319 | |
320 | /* called from driver core with dev locked */ |
321 | static int usb_probe_interface(struct device *dev) |
322 | { |
323 | struct usb_driver *driver = to_usb_driver(dev->driver); |
324 | struct usb_interface *intf = to_usb_interface(dev); |
325 | struct usb_device *udev = interface_to_usbdev(intf); |
326 | const struct usb_device_id *id; |
327 | int error = -ENODEV; |
328 | int lpm_disable_error = -ENODEV; |
329 | |
330 | dev_dbg(dev, "%s\n" , __func__); |
331 | |
332 | intf->needs_binding = 0; |
333 | |
334 | if (usb_device_is_owned(udev)) |
335 | return error; |
336 | |
337 | if (udev->authorized == 0) { |
338 | dev_err(&intf->dev, "Device is not authorized for usage\n" ); |
339 | return error; |
340 | } else if (intf->authorized == 0) { |
341 | dev_err(&intf->dev, "Interface %d is not authorized for usage\n" , |
342 | intf->altsetting->desc.bInterfaceNumber); |
343 | return error; |
344 | } |
345 | |
346 | id = usb_match_dynamic_id(intf, drv: driver); |
347 | if (!id) |
348 | id = usb_match_id(interface: intf, id: driver->id_table); |
349 | if (!id) |
350 | return error; |
351 | |
352 | dev_dbg(dev, "%s - got id\n" , __func__); |
353 | |
354 | error = usb_autoresume_device(udev); |
355 | if (error) |
356 | return error; |
357 | |
358 | intf->condition = USB_INTERFACE_BINDING; |
359 | |
360 | /* Probed interfaces are initially active. They are |
361 | * runtime-PM-enabled only if the driver has autosuspend support. |
362 | * They are sensitive to their children's power states. |
363 | */ |
364 | pm_runtime_set_active(dev); |
365 | pm_suspend_ignore_children(dev, enable: false); |
366 | if (driver->supports_autosuspend) |
367 | pm_runtime_enable(dev); |
368 | |
369 | /* If the new driver doesn't allow hub-initiated LPM, and we can't |
370 | * disable hub-initiated LPM, then fail the probe. |
371 | * |
372 | * Otherwise, leaving LPM enabled should be harmless, because the |
373 | * endpoint intervals should remain the same, and the U1/U2 timeouts |
374 | * should remain the same. |
375 | * |
376 | * If we need to install alt setting 0 before probe, or another alt |
377 | * setting during probe, that should also be fine. usb_set_interface() |
378 | * will attempt to disable LPM, and fail if it can't disable it. |
379 | */ |
380 | if (driver->disable_hub_initiated_lpm) { |
381 | lpm_disable_error = usb_unlocked_disable_lpm(udev); |
382 | if (lpm_disable_error) { |
383 | dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n" , |
384 | __func__, driver->name); |
385 | error = lpm_disable_error; |
386 | goto err; |
387 | } |
388 | } |
389 | |
390 | /* Carry out a deferred switch to altsetting 0 */ |
391 | if (intf->needs_altsetting0) { |
392 | error = usb_set_interface(dev: udev, ifnum: intf->altsetting[0]. |
393 | desc.bInterfaceNumber, alternate: 0); |
394 | if (error < 0) |
395 | goto err; |
396 | intf->needs_altsetting0 = 0; |
397 | } |
398 | |
399 | error = driver->probe(intf, id); |
400 | if (error) |
401 | goto err; |
402 | |
403 | intf->condition = USB_INTERFACE_BOUND; |
404 | |
405 | /* If the LPM disable succeeded, balance the ref counts. */ |
406 | if (!lpm_disable_error) |
407 | usb_unlocked_enable_lpm(udev); |
408 | |
409 | usb_autosuspend_device(udev); |
410 | return error; |
411 | |
412 | err: |
413 | usb_set_intfdata(intf, NULL); |
414 | intf->needs_remote_wakeup = 0; |
415 | intf->condition = USB_INTERFACE_UNBOUND; |
416 | |
417 | /* If the LPM disable succeeded, balance the ref counts. */ |
418 | if (!lpm_disable_error) |
419 | usb_unlocked_enable_lpm(udev); |
420 | |
421 | /* Unbound interfaces are always runtime-PM-disabled and -suspended */ |
422 | if (driver->supports_autosuspend) |
423 | pm_runtime_disable(dev); |
424 | pm_runtime_set_suspended(dev); |
425 | |
426 | usb_autosuspend_device(udev); |
427 | return error; |
428 | } |
429 | |
430 | /* called from driver core with dev locked */ |
431 | static int usb_unbind_interface(struct device *dev) |
432 | { |
433 | struct usb_driver *driver = to_usb_driver(dev->driver); |
434 | struct usb_interface *intf = to_usb_interface(dev); |
435 | struct usb_host_endpoint *ep, **eps = NULL; |
436 | struct usb_device *udev; |
437 | int i, j, error, r; |
438 | int lpm_disable_error = -ENODEV; |
439 | |
440 | intf->condition = USB_INTERFACE_UNBINDING; |
441 | |
442 | /* Autoresume for set_interface call below */ |
443 | udev = interface_to_usbdev(intf); |
444 | error = usb_autoresume_device(udev); |
445 | |
446 | /* If hub-initiated LPM policy may change, attempt to disable LPM until |
447 | * the driver is unbound. If LPM isn't disabled, that's fine because it |
448 | * wouldn't be enabled unless all the bound interfaces supported |
449 | * hub-initiated LPM. |
450 | */ |
451 | if (driver->disable_hub_initiated_lpm) |
452 | lpm_disable_error = usb_unlocked_disable_lpm(udev); |
453 | |
454 | /* |
455 | * Terminate all URBs for this interface unless the driver |
456 | * supports "soft" unbinding and the device is still present. |
457 | */ |
458 | if (!driver->soft_unbind || udev->state == USB_STATE_NOTATTACHED) |
459 | usb_disable_interface(dev: udev, intf, reset_hardware: false); |
460 | |
461 | driver->disconnect(intf); |
462 | |
463 | /* Free streams */ |
464 | for (i = 0, j = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) { |
465 | ep = &intf->cur_altsetting->endpoint[i]; |
466 | if (ep->streams == 0) |
467 | continue; |
468 | if (j == 0) { |
469 | eps = kmalloc_array(USB_MAXENDPOINTS, size: sizeof(void *), |
470 | GFP_KERNEL); |
471 | if (!eps) |
472 | break; |
473 | } |
474 | eps[j++] = ep; |
475 | } |
476 | if (j) { |
477 | usb_free_streams(interface: intf, eps, num_eps: j, GFP_KERNEL); |
478 | kfree(objp: eps); |
479 | } |
480 | |
481 | /* Reset other interface state. |
482 | * We cannot do a Set-Interface if the device is suspended or |
483 | * if it is prepared for a system sleep (since installing a new |
484 | * altsetting means creating new endpoint device entries). |
485 | * When either of these happens, defer the Set-Interface. |
486 | */ |
487 | if (intf->cur_altsetting->desc.bAlternateSetting == 0) { |
488 | /* Already in altsetting 0 so skip Set-Interface. |
489 | * Just re-enable it without affecting the endpoint toggles. |
490 | */ |
491 | usb_enable_interface(dev: udev, intf, reset_toggles: false); |
492 | } else if (!error && !intf->dev.power.is_prepared) { |
493 | r = usb_set_interface(dev: udev, ifnum: intf->altsetting[0]. |
494 | desc.bInterfaceNumber, alternate: 0); |
495 | if (r < 0) |
496 | intf->needs_altsetting0 = 1; |
497 | } else { |
498 | intf->needs_altsetting0 = 1; |
499 | } |
500 | usb_set_intfdata(intf, NULL); |
501 | |
502 | intf->condition = USB_INTERFACE_UNBOUND; |
503 | intf->needs_remote_wakeup = 0; |
504 | |
505 | /* Attempt to re-enable USB3 LPM, if the disable succeeded. */ |
506 | if (!lpm_disable_error) |
507 | usb_unlocked_enable_lpm(udev); |
508 | |
509 | /* Unbound interfaces are always runtime-PM-disabled and -suspended */ |
510 | if (driver->supports_autosuspend) |
511 | pm_runtime_disable(dev); |
512 | pm_runtime_set_suspended(dev); |
513 | |
514 | if (!error) |
515 | usb_autosuspend_device(udev); |
516 | |
517 | return 0; |
518 | } |
519 | |
520 | /** |
521 | * usb_driver_claim_interface - bind a driver to an interface |
522 | * @driver: the driver to be bound |
523 | * @iface: the interface to which it will be bound; must be in the |
524 | * usb device's active configuration |
525 | * @data: driver data associated with that interface |
526 | * |
527 | * This is used by usb device drivers that need to claim more than one |
528 | * interface on a device when probing (audio and acm are current examples). |
529 | * No device driver should directly modify internal usb_interface or |
530 | * usb_device structure members. |
531 | * |
532 | * Callers must own the device lock, so driver probe() entries don't need |
533 | * extra locking, but other call contexts may need to explicitly claim that |
534 | * lock. |
535 | * |
536 | * Return: 0 on success. |
537 | */ |
538 | int usb_driver_claim_interface(struct usb_driver *driver, |
539 | struct usb_interface *iface, void *data) |
540 | { |
541 | struct device *dev; |
542 | int retval = 0; |
543 | |
544 | if (!iface) |
545 | return -ENODEV; |
546 | |
547 | dev = &iface->dev; |
548 | if (dev->driver) |
549 | return -EBUSY; |
550 | |
551 | /* reject claim if interface is not authorized */ |
552 | if (!iface->authorized) |
553 | return -ENODEV; |
554 | |
555 | dev->driver = &driver->driver; |
556 | usb_set_intfdata(intf: iface, data); |
557 | iface->needs_binding = 0; |
558 | |
559 | iface->condition = USB_INTERFACE_BOUND; |
560 | |
561 | /* Claimed interfaces are initially inactive (suspended) and |
562 | * runtime-PM-enabled, but only if the driver has autosuspend |
563 | * support. Otherwise they are marked active, to prevent the |
564 | * device from being autosuspended, but left disabled. In either |
565 | * case they are sensitive to their children's power states. |
566 | */ |
567 | pm_suspend_ignore_children(dev, enable: false); |
568 | if (driver->supports_autosuspend) |
569 | pm_runtime_enable(dev); |
570 | else |
571 | pm_runtime_set_active(dev); |
572 | |
573 | /* if interface was already added, bind now; else let |
574 | * the future device_add() bind it, bypassing probe() |
575 | */ |
576 | if (device_is_registered(dev)) |
577 | retval = device_bind_driver(dev); |
578 | |
579 | if (retval) { |
580 | dev->driver = NULL; |
581 | usb_set_intfdata(intf: iface, NULL); |
582 | iface->needs_remote_wakeup = 0; |
583 | iface->condition = USB_INTERFACE_UNBOUND; |
584 | |
585 | /* |
586 | * Unbound interfaces are always runtime-PM-disabled |
587 | * and runtime-PM-suspended |
588 | */ |
589 | if (driver->supports_autosuspend) |
590 | pm_runtime_disable(dev); |
591 | pm_runtime_set_suspended(dev); |
592 | } |
593 | |
594 | return retval; |
595 | } |
596 | EXPORT_SYMBOL_GPL(usb_driver_claim_interface); |
597 | |
598 | /** |
599 | * usb_driver_release_interface - unbind a driver from an interface |
600 | * @driver: the driver to be unbound |
601 | * @iface: the interface from which it will be unbound |
602 | * |
603 | * This can be used by drivers to release an interface without waiting |
604 | * for their disconnect() methods to be called. In typical cases this |
605 | * also causes the driver disconnect() method to be called. |
606 | * |
607 | * This call is synchronous, and may not be used in an interrupt context. |
608 | * Callers must own the device lock, so driver disconnect() entries don't |
609 | * need extra locking, but other call contexts may need to explicitly claim |
610 | * that lock. |
611 | */ |
612 | void usb_driver_release_interface(struct usb_driver *driver, |
613 | struct usb_interface *iface) |
614 | { |
615 | struct device *dev = &iface->dev; |
616 | |
617 | /* this should never happen, don't release something that's not ours */ |
618 | if (!dev->driver || dev->driver != &driver->driver) |
619 | return; |
620 | |
621 | /* don't release from within disconnect() */ |
622 | if (iface->condition != USB_INTERFACE_BOUND) |
623 | return; |
624 | iface->condition = USB_INTERFACE_UNBINDING; |
625 | |
626 | /* Release via the driver core only if the interface |
627 | * has already been registered |
628 | */ |
629 | if (device_is_registered(dev)) { |
630 | device_release_driver(dev); |
631 | } else { |
632 | device_lock(dev); |
633 | usb_unbind_interface(dev); |
634 | dev->driver = NULL; |
635 | device_unlock(dev); |
636 | } |
637 | } |
638 | EXPORT_SYMBOL_GPL(usb_driver_release_interface); |
639 | |
640 | /* returns 0 if no match, 1 if match */ |
641 | int usb_match_device(struct usb_device *dev, const struct usb_device_id *id) |
642 | { |
643 | if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) && |
644 | id->idVendor != le16_to_cpu(dev->descriptor.idVendor)) |
645 | return 0; |
646 | |
647 | if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) && |
648 | id->idProduct != le16_to_cpu(dev->descriptor.idProduct)) |
649 | return 0; |
650 | |
651 | /* No need to test id->bcdDevice_lo != 0, since 0 is never |
652 | greater than any unsigned number. */ |
653 | if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) && |
654 | (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice))) |
655 | return 0; |
656 | |
657 | if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) && |
658 | (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice))) |
659 | return 0; |
660 | |
661 | if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) && |
662 | (id->bDeviceClass != dev->descriptor.bDeviceClass)) |
663 | return 0; |
664 | |
665 | if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) && |
666 | (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass)) |
667 | return 0; |
668 | |
669 | if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) && |
670 | (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol)) |
671 | return 0; |
672 | |
673 | return 1; |
674 | } |
675 | |
676 | /* returns 0 if no match, 1 if match */ |
677 | int usb_match_one_id_intf(struct usb_device *dev, |
678 | struct usb_host_interface *intf, |
679 | const struct usb_device_id *id) |
680 | { |
681 | /* The interface class, subclass, protocol and number should never be |
682 | * checked for a match if the device class is Vendor Specific, |
683 | * unless the match record specifies the Vendor ID. */ |
684 | if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC && |
685 | !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) && |
686 | (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS | |
687 | USB_DEVICE_ID_MATCH_INT_SUBCLASS | |
688 | USB_DEVICE_ID_MATCH_INT_PROTOCOL | |
689 | USB_DEVICE_ID_MATCH_INT_NUMBER))) |
690 | return 0; |
691 | |
692 | if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) && |
693 | (id->bInterfaceClass != intf->desc.bInterfaceClass)) |
694 | return 0; |
695 | |
696 | if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) && |
697 | (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass)) |
698 | return 0; |
699 | |
700 | if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) && |
701 | (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol)) |
702 | return 0; |
703 | |
704 | if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) && |
705 | (id->bInterfaceNumber != intf->desc.bInterfaceNumber)) |
706 | return 0; |
707 | |
708 | return 1; |
709 | } |
710 | |
711 | /* returns 0 if no match, 1 if match */ |
712 | int usb_match_one_id(struct usb_interface *interface, |
713 | const struct usb_device_id *id) |
714 | { |
715 | struct usb_host_interface *intf; |
716 | struct usb_device *dev; |
717 | |
718 | /* proc_connectinfo in devio.c may call us with id == NULL. */ |
719 | if (id == NULL) |
720 | return 0; |
721 | |
722 | intf = interface->cur_altsetting; |
723 | dev = interface_to_usbdev(interface); |
724 | |
725 | if (!usb_match_device(dev, id)) |
726 | return 0; |
727 | |
728 | return usb_match_one_id_intf(dev, intf, id); |
729 | } |
730 | EXPORT_SYMBOL_GPL(usb_match_one_id); |
731 | |
732 | /** |
733 | * usb_match_id - find first usb_device_id matching device or interface |
734 | * @interface: the interface of interest |
735 | * @id: array of usb_device_id structures, terminated by zero entry |
736 | * |
737 | * usb_match_id searches an array of usb_device_id's and returns |
738 | * the first one matching the device or interface, or null. |
739 | * This is used when binding (or rebinding) a driver to an interface. |
740 | * Most USB device drivers will use this indirectly, through the usb core, |
741 | * but some layered driver frameworks use it directly. |
742 | * These device tables are exported with MODULE_DEVICE_TABLE, through |
743 | * modutils, to support the driver loading functionality of USB hotplugging. |
744 | * |
745 | * Return: The first matching usb_device_id, or %NULL. |
746 | * |
747 | * What Matches: |
748 | * |
749 | * The "match_flags" element in a usb_device_id controls which |
750 | * members are used. If the corresponding bit is set, the |
751 | * value in the device_id must match its corresponding member |
752 | * in the device or interface descriptor, or else the device_id |
753 | * does not match. |
754 | * |
755 | * "driver_info" is normally used only by device drivers, |
756 | * but you can create a wildcard "matches anything" usb_device_id |
757 | * as a driver's "modules.usbmap" entry if you provide an id with |
758 | * only a nonzero "driver_info" field. If you do this, the USB device |
759 | * driver's probe() routine should use additional intelligence to |
760 | * decide whether to bind to the specified interface. |
761 | * |
762 | * What Makes Good usb_device_id Tables: |
763 | * |
764 | * The match algorithm is very simple, so that intelligence in |
765 | * driver selection must come from smart driver id records. |
766 | * Unless you have good reasons to use another selection policy, |
767 | * provide match elements only in related groups, and order match |
768 | * specifiers from specific to general. Use the macros provided |
769 | * for that purpose if you can. |
770 | * |
771 | * The most specific match specifiers use device descriptor |
772 | * data. These are commonly used with product-specific matches; |
773 | * the USB_DEVICE macro lets you provide vendor and product IDs, |
774 | * and you can also match against ranges of product revisions. |
775 | * These are widely used for devices with application or vendor |
776 | * specific bDeviceClass values. |
777 | * |
778 | * Matches based on device class/subclass/protocol specifications |
779 | * are slightly more general; use the USB_DEVICE_INFO macro, or |
780 | * its siblings. These are used with single-function devices |
781 | * where bDeviceClass doesn't specify that each interface has |
782 | * its own class. |
783 | * |
784 | * Matches based on interface class/subclass/protocol are the |
785 | * most general; they let drivers bind to any interface on a |
786 | * multiple-function device. Use the USB_INTERFACE_INFO |
787 | * macro, or its siblings, to match class-per-interface style |
788 | * devices (as recorded in bInterfaceClass). |
789 | * |
790 | * Note that an entry created by USB_INTERFACE_INFO won't match |
791 | * any interface if the device class is set to Vendor-Specific. |
792 | * This is deliberate; according to the USB spec the meanings of |
793 | * the interface class/subclass/protocol for these devices are also |
794 | * vendor-specific, and hence matching against a standard product |
795 | * class wouldn't work anyway. If you really want to use an |
796 | * interface-based match for such a device, create a match record |
797 | * that also specifies the vendor ID. (Unforunately there isn't a |
798 | * standard macro for creating records like this.) |
799 | * |
800 | * Within those groups, remember that not all combinations are |
801 | * meaningful. For example, don't give a product version range |
802 | * without vendor and product IDs; or specify a protocol without |
803 | * its associated class and subclass. |
804 | */ |
805 | const struct usb_device_id *usb_match_id(struct usb_interface *interface, |
806 | const struct usb_device_id *id) |
807 | { |
808 | /* proc_connectinfo in devio.c may call us with id == NULL. */ |
809 | if (id == NULL) |
810 | return NULL; |
811 | |
812 | /* It is important to check that id->driver_info is nonzero, |
813 | since an entry that is all zeroes except for a nonzero |
814 | id->driver_info is the way to create an entry that |
815 | indicates that the driver want to examine every |
816 | device and interface. */ |
817 | for (; id->idVendor || id->idProduct || id->bDeviceClass || |
818 | id->bInterfaceClass || id->driver_info; id++) { |
819 | if (usb_match_one_id(interface, id)) |
820 | return id; |
821 | } |
822 | |
823 | return NULL; |
824 | } |
825 | EXPORT_SYMBOL_GPL(usb_match_id); |
826 | |
827 | const struct usb_device_id *usb_device_match_id(struct usb_device *udev, |
828 | const struct usb_device_id *id) |
829 | { |
830 | if (!id) |
831 | return NULL; |
832 | |
833 | for (; id->idVendor || id->idProduct ; id++) { |
834 | if (usb_match_device(dev: udev, id)) |
835 | return id; |
836 | } |
837 | |
838 | return NULL; |
839 | } |
840 | EXPORT_SYMBOL_GPL(usb_device_match_id); |
841 | |
842 | bool usb_driver_applicable(struct usb_device *udev, |
843 | struct usb_device_driver *udrv) |
844 | { |
845 | if (udrv->id_table && udrv->match) |
846 | return usb_device_match_id(udev, udrv->id_table) != NULL && |
847 | udrv->match(udev); |
848 | |
849 | if (udrv->id_table) |
850 | return usb_device_match_id(udev, udrv->id_table) != NULL; |
851 | |
852 | if (udrv->match) |
853 | return udrv->match(udev); |
854 | |
855 | return false; |
856 | } |
857 | |
858 | static int usb_device_match(struct device *dev, struct device_driver *drv) |
859 | { |
860 | /* devices and interfaces are handled separately */ |
861 | if (is_usb_device(dev)) { |
862 | struct usb_device *udev; |
863 | struct usb_device_driver *udrv; |
864 | |
865 | /* interface drivers never match devices */ |
866 | if (!is_usb_device_driver(drv)) |
867 | return 0; |
868 | |
869 | udev = to_usb_device(dev); |
870 | udrv = to_usb_device_driver(drv); |
871 | |
872 | /* If the device driver under consideration does not have a |
873 | * id_table or a match function, then let the driver's probe |
874 | * function decide. |
875 | */ |
876 | if (!udrv->id_table && !udrv->match) |
877 | return 1; |
878 | |
879 | return usb_driver_applicable(udev, udrv); |
880 | |
881 | } else if (is_usb_interface(dev)) { |
882 | struct usb_interface *intf; |
883 | struct usb_driver *usb_drv; |
884 | const struct usb_device_id *id; |
885 | |
886 | /* device drivers never match interfaces */ |
887 | if (is_usb_device_driver(drv)) |
888 | return 0; |
889 | |
890 | intf = to_usb_interface(dev); |
891 | usb_drv = to_usb_driver(drv); |
892 | |
893 | id = usb_match_id(intf, usb_drv->id_table); |
894 | if (id) |
895 | return 1; |
896 | |
897 | id = usb_match_dynamic_id(intf, drv: usb_drv); |
898 | if (id) |
899 | return 1; |
900 | } |
901 | |
902 | return 0; |
903 | } |
904 | |
905 | static int usb_uevent(const struct device *dev, struct kobj_uevent_env *env) |
906 | { |
907 | const struct usb_device *usb_dev; |
908 | |
909 | if (is_usb_device(dev)) { |
910 | usb_dev = to_usb_device(dev); |
911 | } else if (is_usb_interface(dev)) { |
912 | const struct usb_interface *intf = to_usb_interface(dev); |
913 | |
914 | usb_dev = interface_to_usbdev(intf); |
915 | } else { |
916 | return 0; |
917 | } |
918 | |
919 | if (usb_dev->devnum < 0) { |
920 | /* driver is often null here; dev_dbg() would oops */ |
921 | pr_debug("usb %s: already deleted?\n" , dev_name(dev)); |
922 | return -ENODEV; |
923 | } |
924 | if (!usb_dev->bus) { |
925 | pr_debug("usb %s: bus removed?\n" , dev_name(dev)); |
926 | return -ENODEV; |
927 | } |
928 | |
929 | /* per-device configurations are common */ |
930 | if (add_uevent_var(env, format: "PRODUCT=%x/%x/%x" , |
931 | le16_to_cpu(usb_dev->descriptor.idVendor), |
932 | le16_to_cpu(usb_dev->descriptor.idProduct), |
933 | le16_to_cpu(usb_dev->descriptor.bcdDevice))) |
934 | return -ENOMEM; |
935 | |
936 | /* class-based driver binding models */ |
937 | if (add_uevent_var(env, format: "TYPE=%d/%d/%d" , |
938 | usb_dev->descriptor.bDeviceClass, |
939 | usb_dev->descriptor.bDeviceSubClass, |
940 | usb_dev->descriptor.bDeviceProtocol)) |
941 | return -ENOMEM; |
942 | |
943 | return 0; |
944 | } |
945 | |
946 | static int __usb_bus_reprobe_drivers(struct device *dev, void *data) |
947 | { |
948 | struct usb_device_driver *new_udriver = data; |
949 | struct usb_device *udev; |
950 | int ret; |
951 | |
952 | /* Don't reprobe if current driver isn't usb_generic_driver */ |
953 | if (dev->driver != &usb_generic_driver.driver) |
954 | return 0; |
955 | |
956 | udev = to_usb_device(dev); |
957 | if (!usb_driver_applicable(udev, udrv: new_udriver)) |
958 | return 0; |
959 | |
960 | ret = device_reprobe(dev); |
961 | if (ret && ret != -EPROBE_DEFER) |
962 | dev_err(dev, "Failed to reprobe device (error %d)\n" , ret); |
963 | |
964 | return 0; |
965 | } |
966 | |
967 | bool is_usb_device_driver(const struct device_driver *drv) |
968 | { |
969 | return drv->probe == usb_probe_device; |
970 | } |
971 | |
972 | /** |
973 | * usb_register_device_driver - register a USB device (not interface) driver |
974 | * @new_udriver: USB operations for the device driver |
975 | * @owner: module owner of this driver. |
976 | * |
977 | * Registers a USB device driver with the USB core. The list of |
978 | * unattached devices will be rescanned whenever a new driver is |
979 | * added, allowing the new driver to attach to any recognized devices. |
980 | * |
981 | * Return: A negative error code on failure and 0 on success. |
982 | */ |
983 | int usb_register_device_driver(struct usb_device_driver *new_udriver, |
984 | struct module *owner) |
985 | { |
986 | int retval = 0; |
987 | |
988 | if (usb_disabled()) |
989 | return -ENODEV; |
990 | |
991 | new_udriver->driver.name = new_udriver->name; |
992 | new_udriver->driver.bus = &usb_bus_type; |
993 | new_udriver->driver.probe = usb_probe_device; |
994 | new_udriver->driver.remove = usb_unbind_device; |
995 | new_udriver->driver.owner = owner; |
996 | new_udriver->driver.dev_groups = new_udriver->dev_groups; |
997 | |
998 | retval = driver_register(drv: &new_udriver->driver); |
999 | |
1000 | if (!retval) { |
1001 | pr_info("%s: registered new device driver %s\n" , |
1002 | usbcore_name, new_udriver->name); |
1003 | /* |
1004 | * Check whether any device could be better served with |
1005 | * this new driver |
1006 | */ |
1007 | bus_for_each_dev(bus: &usb_bus_type, NULL, data: new_udriver, |
1008 | fn: __usb_bus_reprobe_drivers); |
1009 | } else { |
1010 | pr_err("%s: error %d registering device driver %s\n" , |
1011 | usbcore_name, retval, new_udriver->name); |
1012 | } |
1013 | |
1014 | return retval; |
1015 | } |
1016 | EXPORT_SYMBOL_GPL(usb_register_device_driver); |
1017 | |
1018 | /** |
1019 | * usb_deregister_device_driver - unregister a USB device (not interface) driver |
1020 | * @udriver: USB operations of the device driver to unregister |
1021 | * Context: must be able to sleep |
1022 | * |
1023 | * Unlinks the specified driver from the internal USB driver list. |
1024 | */ |
1025 | void usb_deregister_device_driver(struct usb_device_driver *udriver) |
1026 | { |
1027 | pr_info("%s: deregistering device driver %s\n" , |
1028 | usbcore_name, udriver->name); |
1029 | |
1030 | driver_unregister(drv: &udriver->driver); |
1031 | } |
1032 | EXPORT_SYMBOL_GPL(usb_deregister_device_driver); |
1033 | |
1034 | /** |
1035 | * usb_register_driver - register a USB interface driver |
1036 | * @new_driver: USB operations for the interface driver |
1037 | * @owner: module owner of this driver. |
1038 | * @mod_name: module name string |
1039 | * |
1040 | * Registers a USB interface driver with the USB core. The list of |
1041 | * unattached interfaces will be rescanned whenever a new driver is |
1042 | * added, allowing the new driver to attach to any recognized interfaces. |
1043 | * |
1044 | * Return: A negative error code on failure and 0 on success. |
1045 | * |
1046 | * NOTE: if you want your driver to use the USB major number, you must call |
1047 | * usb_register_dev() to enable that functionality. This function no longer |
1048 | * takes care of that. |
1049 | */ |
1050 | int usb_register_driver(struct usb_driver *new_driver, struct module *owner, |
1051 | const char *mod_name) |
1052 | { |
1053 | int retval = 0; |
1054 | |
1055 | if (usb_disabled()) |
1056 | return -ENODEV; |
1057 | |
1058 | new_driver->driver.name = new_driver->name; |
1059 | new_driver->driver.bus = &usb_bus_type; |
1060 | new_driver->driver.probe = usb_probe_interface; |
1061 | new_driver->driver.remove = usb_unbind_interface; |
1062 | new_driver->driver.owner = owner; |
1063 | new_driver->driver.mod_name = mod_name; |
1064 | new_driver->driver.dev_groups = new_driver->dev_groups; |
1065 | spin_lock_init(&new_driver->dynids.lock); |
1066 | INIT_LIST_HEAD(list: &new_driver->dynids.list); |
1067 | |
1068 | retval = driver_register(drv: &new_driver->driver); |
1069 | if (retval) |
1070 | goto out; |
1071 | |
1072 | retval = usb_create_newid_files(usb_drv: new_driver); |
1073 | if (retval) |
1074 | goto out_newid; |
1075 | |
1076 | pr_info("%s: registered new interface driver %s\n" , |
1077 | usbcore_name, new_driver->name); |
1078 | |
1079 | out: |
1080 | return retval; |
1081 | |
1082 | out_newid: |
1083 | driver_unregister(drv: &new_driver->driver); |
1084 | |
1085 | pr_err("%s: error %d registering interface driver %s\n" , |
1086 | usbcore_name, retval, new_driver->name); |
1087 | goto out; |
1088 | } |
1089 | EXPORT_SYMBOL_GPL(usb_register_driver); |
1090 | |
1091 | /** |
1092 | * usb_deregister - unregister a USB interface driver |
1093 | * @driver: USB operations of the interface driver to unregister |
1094 | * Context: must be able to sleep |
1095 | * |
1096 | * Unlinks the specified driver from the internal USB driver list. |
1097 | * |
1098 | * NOTE: If you called usb_register_dev(), you still need to call |
1099 | * usb_deregister_dev() to clean up your driver's allocated minor numbers, |
1100 | * this * call will no longer do it for you. |
1101 | */ |
1102 | void usb_deregister(struct usb_driver *driver) |
1103 | { |
1104 | pr_info("%s: deregistering interface driver %s\n" , |
1105 | usbcore_name, driver->name); |
1106 | |
1107 | usb_remove_newid_files(usb_drv: driver); |
1108 | driver_unregister(drv: &driver->driver); |
1109 | usb_free_dynids(usb_drv: driver); |
1110 | } |
1111 | EXPORT_SYMBOL_GPL(usb_deregister); |
1112 | |
1113 | /* Forced unbinding of a USB interface driver, either because |
1114 | * it doesn't support pre_reset/post_reset/reset_resume or |
1115 | * because it doesn't support suspend/resume. |
1116 | * |
1117 | * The caller must hold @intf's device's lock, but not @intf's lock. |
1118 | */ |
1119 | void usb_forced_unbind_intf(struct usb_interface *intf) |
1120 | { |
1121 | struct usb_driver *driver = to_usb_driver(intf->dev.driver); |
1122 | |
1123 | dev_dbg(&intf->dev, "forced unbind\n" ); |
1124 | usb_driver_release_interface(driver, intf); |
1125 | |
1126 | /* Mark the interface for later rebinding */ |
1127 | intf->needs_binding = 1; |
1128 | } |
1129 | |
1130 | /* |
1131 | * Unbind drivers for @udev's marked interfaces. These interfaces have |
1132 | * the needs_binding flag set, for example by usb_resume_interface(). |
1133 | * |
1134 | * The caller must hold @udev's device lock. |
1135 | */ |
1136 | static void unbind_marked_interfaces(struct usb_device *udev) |
1137 | { |
1138 | struct usb_host_config *config; |
1139 | int i; |
1140 | struct usb_interface *intf; |
1141 | |
1142 | config = udev->actconfig; |
1143 | if (config) { |
1144 | for (i = 0; i < config->desc.bNumInterfaces; ++i) { |
1145 | intf = config->interface[i]; |
1146 | if (intf->dev.driver && intf->needs_binding) |
1147 | usb_forced_unbind_intf(intf); |
1148 | } |
1149 | } |
1150 | } |
1151 | |
1152 | /* Delayed forced unbinding of a USB interface driver and scan |
1153 | * for rebinding. |
1154 | * |
1155 | * The caller must hold @intf's device's lock, but not @intf's lock. |
1156 | * |
1157 | * Note: Rebinds will be skipped if a system sleep transition is in |
1158 | * progress and the PM "complete" callback hasn't occurred yet. |
1159 | */ |
1160 | static void usb_rebind_intf(struct usb_interface *intf) |
1161 | { |
1162 | int rc; |
1163 | |
1164 | /* Delayed unbind of an existing driver */ |
1165 | if (intf->dev.driver) |
1166 | usb_forced_unbind_intf(intf); |
1167 | |
1168 | /* Try to rebind the interface */ |
1169 | if (!intf->dev.power.is_prepared) { |
1170 | intf->needs_binding = 0; |
1171 | rc = device_attach(dev: &intf->dev); |
1172 | if (rc < 0 && rc != -EPROBE_DEFER) |
1173 | dev_warn(&intf->dev, "rebind failed: %d\n" , rc); |
1174 | } |
1175 | } |
1176 | |
1177 | /* |
1178 | * Rebind drivers to @udev's marked interfaces. These interfaces have |
1179 | * the needs_binding flag set. |
1180 | * |
1181 | * The caller must hold @udev's device lock. |
1182 | */ |
1183 | static void rebind_marked_interfaces(struct usb_device *udev) |
1184 | { |
1185 | struct usb_host_config *config; |
1186 | int i; |
1187 | struct usb_interface *intf; |
1188 | |
1189 | config = udev->actconfig; |
1190 | if (config) { |
1191 | for (i = 0; i < config->desc.bNumInterfaces; ++i) { |
1192 | intf = config->interface[i]; |
1193 | if (intf->needs_binding) |
1194 | usb_rebind_intf(intf); |
1195 | } |
1196 | } |
1197 | } |
1198 | |
1199 | /* |
1200 | * Unbind all of @udev's marked interfaces and then rebind all of them. |
1201 | * This ordering is necessary because some drivers claim several interfaces |
1202 | * when they are first probed. |
1203 | * |
1204 | * The caller must hold @udev's device lock. |
1205 | */ |
1206 | void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev) |
1207 | { |
1208 | unbind_marked_interfaces(udev); |
1209 | rebind_marked_interfaces(udev); |
1210 | } |
1211 | |
1212 | #ifdef CONFIG_PM |
1213 | |
1214 | /* Unbind drivers for @udev's interfaces that don't support suspend/resume |
1215 | * There is no check for reset_resume here because it can be determined |
1216 | * only during resume whether reset_resume is needed. |
1217 | * |
1218 | * The caller must hold @udev's device lock. |
1219 | */ |
1220 | static void unbind_no_pm_drivers_interfaces(struct usb_device *udev) |
1221 | { |
1222 | struct usb_host_config *config; |
1223 | int i; |
1224 | struct usb_interface *intf; |
1225 | struct usb_driver *drv; |
1226 | |
1227 | config = udev->actconfig; |
1228 | if (config) { |
1229 | for (i = 0; i < config->desc.bNumInterfaces; ++i) { |
1230 | intf = config->interface[i]; |
1231 | |
1232 | if (intf->dev.driver) { |
1233 | drv = to_usb_driver(intf->dev.driver); |
1234 | if (!drv->suspend || !drv->resume) |
1235 | usb_forced_unbind_intf(intf); |
1236 | } |
1237 | } |
1238 | } |
1239 | } |
1240 | |
1241 | static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) |
1242 | { |
1243 | struct usb_device_driver *udriver; |
1244 | int status = 0; |
1245 | |
1246 | if (udev->state == USB_STATE_NOTATTACHED || |
1247 | udev->state == USB_STATE_SUSPENDED) |
1248 | goto done; |
1249 | |
1250 | /* For devices that don't have a driver, we do a generic suspend. */ |
1251 | if (udev->dev.driver) |
1252 | udriver = to_usb_device_driver(udev->dev.driver); |
1253 | else { |
1254 | udev->do_remote_wakeup = 0; |
1255 | udriver = &usb_generic_driver; |
1256 | } |
1257 | if (udriver->suspend) |
1258 | status = udriver->suspend(udev, msg); |
1259 | if (status == 0 && udriver->generic_subclass) |
1260 | status = usb_generic_driver_suspend(udev, msg); |
1261 | |
1262 | done: |
1263 | dev_vdbg(&udev->dev, "%s: status %d\n" , __func__, status); |
1264 | return status; |
1265 | } |
1266 | |
1267 | static int usb_resume_device(struct usb_device *udev, pm_message_t msg) |
1268 | { |
1269 | struct usb_device_driver *udriver; |
1270 | int status = 0; |
1271 | |
1272 | if (udev->state == USB_STATE_NOTATTACHED) |
1273 | goto done; |
1274 | |
1275 | /* Can't resume it if it doesn't have a driver. */ |
1276 | if (udev->dev.driver == NULL) { |
1277 | status = -ENOTCONN; |
1278 | goto done; |
1279 | } |
1280 | |
1281 | /* Non-root devices on a full/low-speed bus must wait for their |
1282 | * companion high-speed root hub, in case a handoff is needed. |
1283 | */ |
1284 | if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion) |
1285 | device_pm_wait_for_dev(sub: &udev->dev, |
1286 | dev: &udev->bus->hs_companion->root_hub->dev); |
1287 | |
1288 | if (udev->quirks & USB_QUIRK_RESET_RESUME) |
1289 | udev->reset_resume = 1; |
1290 | |
1291 | udriver = to_usb_device_driver(udev->dev.driver); |
1292 | if (udriver->generic_subclass) |
1293 | status = usb_generic_driver_resume(udev, msg); |
1294 | if (status == 0 && udriver->resume) |
1295 | status = udriver->resume(udev, msg); |
1296 | |
1297 | done: |
1298 | dev_vdbg(&udev->dev, "%s: status %d\n" , __func__, status); |
1299 | return status; |
1300 | } |
1301 | |
1302 | static int usb_suspend_interface(struct usb_device *udev, |
1303 | struct usb_interface *intf, pm_message_t msg) |
1304 | { |
1305 | struct usb_driver *driver; |
1306 | int status = 0; |
1307 | |
1308 | if (udev->state == USB_STATE_NOTATTACHED || |
1309 | intf->condition == USB_INTERFACE_UNBOUND) |
1310 | goto done; |
1311 | driver = to_usb_driver(intf->dev.driver); |
1312 | |
1313 | /* at this time we know the driver supports suspend */ |
1314 | status = driver->suspend(intf, msg); |
1315 | if (status && !PMSG_IS_AUTO(msg)) |
1316 | dev_err(&intf->dev, "suspend error %d\n" , status); |
1317 | |
1318 | done: |
1319 | dev_vdbg(&intf->dev, "%s: status %d\n" , __func__, status); |
1320 | return status; |
1321 | } |
1322 | |
1323 | static int usb_resume_interface(struct usb_device *udev, |
1324 | struct usb_interface *intf, pm_message_t msg, int reset_resume) |
1325 | { |
1326 | struct usb_driver *driver; |
1327 | int status = 0; |
1328 | |
1329 | if (udev->state == USB_STATE_NOTATTACHED) |
1330 | goto done; |
1331 | |
1332 | /* Don't let autoresume interfere with unbinding */ |
1333 | if (intf->condition == USB_INTERFACE_UNBINDING) |
1334 | goto done; |
1335 | |
1336 | /* Can't resume it if it doesn't have a driver. */ |
1337 | if (intf->condition == USB_INTERFACE_UNBOUND) { |
1338 | |
1339 | /* Carry out a deferred switch to altsetting 0 */ |
1340 | if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) { |
1341 | usb_set_interface(dev: udev, ifnum: intf->altsetting[0]. |
1342 | desc.bInterfaceNumber, alternate: 0); |
1343 | intf->needs_altsetting0 = 0; |
1344 | } |
1345 | goto done; |
1346 | } |
1347 | |
1348 | /* Don't resume if the interface is marked for rebinding */ |
1349 | if (intf->needs_binding) |
1350 | goto done; |
1351 | driver = to_usb_driver(intf->dev.driver); |
1352 | |
1353 | if (reset_resume) { |
1354 | if (driver->reset_resume) { |
1355 | status = driver->reset_resume(intf); |
1356 | if (status) |
1357 | dev_err(&intf->dev, "%s error %d\n" , |
1358 | "reset_resume" , status); |
1359 | } else { |
1360 | intf->needs_binding = 1; |
1361 | dev_dbg(&intf->dev, "no reset_resume for driver %s?\n" , |
1362 | driver->name); |
1363 | } |
1364 | } else { |
1365 | status = driver->resume(intf); |
1366 | if (status) |
1367 | dev_err(&intf->dev, "resume error %d\n" , status); |
1368 | } |
1369 | |
1370 | done: |
1371 | dev_vdbg(&intf->dev, "%s: status %d\n" , __func__, status); |
1372 | |
1373 | /* Later we will unbind the driver and/or reprobe, if necessary */ |
1374 | return status; |
1375 | } |
1376 | |
1377 | /** |
1378 | * usb_suspend_both - suspend a USB device and its interfaces |
1379 | * @udev: the usb_device to suspend |
1380 | * @msg: Power Management message describing this state transition |
1381 | * |
1382 | * This is the central routine for suspending USB devices. It calls the |
1383 | * suspend methods for all the interface drivers in @udev and then calls |
1384 | * the suspend method for @udev itself. When the routine is called in |
1385 | * autosuspend, if an error occurs at any stage, all the interfaces |
1386 | * which were suspended are resumed so that they remain in the same |
1387 | * state as the device, but when called from system sleep, all error |
1388 | * from suspend methods of interfaces and the non-root-hub device itself |
1389 | * are simply ignored, so all suspended interfaces are only resumed |
1390 | * to the device's state when @udev is root-hub and its suspend method |
1391 | * returns failure. |
1392 | * |
1393 | * Autosuspend requests originating from a child device or an interface |
1394 | * driver may be made without the protection of @udev's device lock, but |
1395 | * all other suspend calls will hold the lock. Usbcore will insure that |
1396 | * method calls do not arrive during bind, unbind, or reset operations. |
1397 | * However drivers must be prepared to handle suspend calls arriving at |
1398 | * unpredictable times. |
1399 | * |
1400 | * This routine can run only in process context. |
1401 | * |
1402 | * Return: 0 if the suspend succeeded. |
1403 | */ |
1404 | static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) |
1405 | { |
1406 | int status = 0; |
1407 | int i = 0, n = 0; |
1408 | struct usb_interface *intf; |
1409 | |
1410 | if (udev->state == USB_STATE_NOTATTACHED || |
1411 | udev->state == USB_STATE_SUSPENDED) |
1412 | goto done; |
1413 | |
1414 | /* Suspend all the interfaces and then udev itself */ |
1415 | if (udev->actconfig) { |
1416 | n = udev->actconfig->desc.bNumInterfaces; |
1417 | for (i = n - 1; i >= 0; --i) { |
1418 | intf = udev->actconfig->interface[i]; |
1419 | status = usb_suspend_interface(udev, intf, msg); |
1420 | |
1421 | /* Ignore errors during system sleep transitions */ |
1422 | if (!PMSG_IS_AUTO(msg)) |
1423 | status = 0; |
1424 | if (status != 0) |
1425 | break; |
1426 | } |
1427 | } |
1428 | if (status == 0) { |
1429 | status = usb_suspend_device(udev, msg); |
1430 | |
1431 | /* |
1432 | * Ignore errors from non-root-hub devices during |
1433 | * system sleep transitions. For the most part, |
1434 | * these devices should go to low power anyway when |
1435 | * the entire bus is suspended. |
1436 | */ |
1437 | if (udev->parent && !PMSG_IS_AUTO(msg)) |
1438 | status = 0; |
1439 | |
1440 | /* |
1441 | * If the device is inaccessible, don't try to resume |
1442 | * suspended interfaces and just return the error. |
1443 | */ |
1444 | if (status && status != -EBUSY) { |
1445 | int err; |
1446 | u16 devstat; |
1447 | |
1448 | err = usb_get_std_status(dev: udev, USB_RECIP_DEVICE, target: 0, |
1449 | data: &devstat); |
1450 | if (err) { |
1451 | dev_err(&udev->dev, |
1452 | "Failed to suspend device, error %d\n" , |
1453 | status); |
1454 | goto done; |
1455 | } |
1456 | } |
1457 | } |
1458 | |
1459 | /* If the suspend failed, resume interfaces that did get suspended */ |
1460 | if (status != 0) { |
1461 | if (udev->actconfig) { |
1462 | msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME); |
1463 | while (++i < n) { |
1464 | intf = udev->actconfig->interface[i]; |
1465 | usb_resume_interface(udev, intf, msg, reset_resume: 0); |
1466 | } |
1467 | } |
1468 | |
1469 | /* If the suspend succeeded then prevent any more URB submissions |
1470 | * and flush any outstanding URBs. |
1471 | */ |
1472 | } else { |
1473 | udev->can_submit = 0; |
1474 | for (i = 0; i < 16; ++i) { |
1475 | usb_hcd_flush_endpoint(udev, ep: udev->ep_out[i]); |
1476 | usb_hcd_flush_endpoint(udev, ep: udev->ep_in[i]); |
1477 | } |
1478 | } |
1479 | |
1480 | done: |
1481 | dev_vdbg(&udev->dev, "%s: status %d\n" , __func__, status); |
1482 | return status; |
1483 | } |
1484 | |
1485 | /** |
1486 | * usb_resume_both - resume a USB device and its interfaces |
1487 | * @udev: the usb_device to resume |
1488 | * @msg: Power Management message describing this state transition |
1489 | * |
1490 | * This is the central routine for resuming USB devices. It calls the |
1491 | * resume method for @udev and then calls the resume methods for all |
1492 | * the interface drivers in @udev. |
1493 | * |
1494 | * Autoresume requests originating from a child device or an interface |
1495 | * driver may be made without the protection of @udev's device lock, but |
1496 | * all other resume calls will hold the lock. Usbcore will insure that |
1497 | * method calls do not arrive during bind, unbind, or reset operations. |
1498 | * However drivers must be prepared to handle resume calls arriving at |
1499 | * unpredictable times. |
1500 | * |
1501 | * This routine can run only in process context. |
1502 | * |
1503 | * Return: 0 on success. |
1504 | */ |
1505 | static int usb_resume_both(struct usb_device *udev, pm_message_t msg) |
1506 | { |
1507 | int status = 0; |
1508 | int i; |
1509 | struct usb_interface *intf; |
1510 | |
1511 | if (udev->state == USB_STATE_NOTATTACHED) { |
1512 | status = -ENODEV; |
1513 | goto done; |
1514 | } |
1515 | udev->can_submit = 1; |
1516 | |
1517 | /* Resume the device */ |
1518 | if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) |
1519 | status = usb_resume_device(udev, msg); |
1520 | |
1521 | /* Resume the interfaces */ |
1522 | if (status == 0 && udev->actconfig) { |
1523 | for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { |
1524 | intf = udev->actconfig->interface[i]; |
1525 | usb_resume_interface(udev, intf, msg, |
1526 | reset_resume: udev->reset_resume); |
1527 | } |
1528 | } |
1529 | usb_mark_last_busy(udev); |
1530 | |
1531 | done: |
1532 | dev_vdbg(&udev->dev, "%s: status %d\n" , __func__, status); |
1533 | if (!status) |
1534 | udev->reset_resume = 0; |
1535 | return status; |
1536 | } |
1537 | |
1538 | static void choose_wakeup(struct usb_device *udev, pm_message_t msg) |
1539 | { |
1540 | int w; |
1541 | |
1542 | /* |
1543 | * For FREEZE/QUIESCE, disable remote wakeups so no interrupts get |
1544 | * generated. |
1545 | */ |
1546 | if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) { |
1547 | w = 0; |
1548 | |
1549 | } else { |
1550 | /* |
1551 | * Enable remote wakeup if it is allowed, even if no interface |
1552 | * drivers actually want it. |
1553 | */ |
1554 | w = device_may_wakeup(dev: &udev->dev); |
1555 | } |
1556 | |
1557 | /* |
1558 | * If the device is autosuspended with the wrong wakeup setting, |
1559 | * autoresume now so the setting can be changed. |
1560 | */ |
1561 | if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup) |
1562 | pm_runtime_resume(dev: &udev->dev); |
1563 | udev->do_remote_wakeup = w; |
1564 | } |
1565 | |
1566 | /* The device lock is held by the PM core */ |
1567 | int usb_suspend(struct device *dev, pm_message_t msg) |
1568 | { |
1569 | struct usb_device *udev = to_usb_device(dev); |
1570 | int r; |
1571 | |
1572 | unbind_no_pm_drivers_interfaces(udev); |
1573 | |
1574 | /* From now on we are sure all drivers support suspend/resume |
1575 | * but not necessarily reset_resume() |
1576 | * so we may still need to unbind and rebind upon resume |
1577 | */ |
1578 | choose_wakeup(udev, msg); |
1579 | r = usb_suspend_both(udev, msg); |
1580 | if (r) |
1581 | return r; |
1582 | |
1583 | if (udev->quirks & USB_QUIRK_DISCONNECT_SUSPEND) |
1584 | usb_port_disable(udev); |
1585 | |
1586 | return 0; |
1587 | } |
1588 | |
1589 | /* The device lock is held by the PM core */ |
1590 | int usb_resume_complete(struct device *dev) |
1591 | { |
1592 | struct usb_device *udev = to_usb_device(dev); |
1593 | |
1594 | /* For PM complete calls, all we do is rebind interfaces |
1595 | * whose needs_binding flag is set |
1596 | */ |
1597 | if (udev->state != USB_STATE_NOTATTACHED) |
1598 | rebind_marked_interfaces(udev); |
1599 | return 0; |
1600 | } |
1601 | |
1602 | /* The device lock is held by the PM core */ |
1603 | int usb_resume(struct device *dev, pm_message_t msg) |
1604 | { |
1605 | struct usb_device *udev = to_usb_device(dev); |
1606 | int status; |
1607 | |
1608 | /* For all calls, take the device back to full power and |
1609 | * tell the PM core in case it was autosuspended previously. |
1610 | * Unbind the interfaces that will need rebinding later, |
1611 | * because they fail to support reset_resume. |
1612 | * (This can't be done in usb_resume_interface() |
1613 | * above because it doesn't own the right set of locks.) |
1614 | */ |
1615 | status = usb_resume_both(udev, msg); |
1616 | if (status == 0) { |
1617 | pm_runtime_disable(dev); |
1618 | pm_runtime_set_active(dev); |
1619 | pm_runtime_enable(dev); |
1620 | unbind_marked_interfaces(udev); |
1621 | } |
1622 | |
1623 | /* Avoid PM error messages for devices disconnected while suspended |
1624 | * as we'll display regular disconnect messages just a bit later. |
1625 | */ |
1626 | if (status == -ENODEV || status == -ESHUTDOWN) |
1627 | status = 0; |
1628 | return status; |
1629 | } |
1630 | |
1631 | /** |
1632 | * usb_enable_autosuspend - allow a USB device to be autosuspended |
1633 | * @udev: the USB device which may be autosuspended |
1634 | * |
1635 | * This routine allows @udev to be autosuspended. An autosuspend won't |
1636 | * take place until the autosuspend_delay has elapsed and all the other |
1637 | * necessary conditions are satisfied. |
1638 | * |
1639 | * The caller must hold @udev's device lock. |
1640 | */ |
1641 | void usb_enable_autosuspend(struct usb_device *udev) |
1642 | { |
1643 | pm_runtime_allow(dev: &udev->dev); |
1644 | } |
1645 | EXPORT_SYMBOL_GPL(usb_enable_autosuspend); |
1646 | |
1647 | /** |
1648 | * usb_disable_autosuspend - prevent a USB device from being autosuspended |
1649 | * @udev: the USB device which may not be autosuspended |
1650 | * |
1651 | * This routine prevents @udev from being autosuspended and wakes it up |
1652 | * if it is already autosuspended. |
1653 | * |
1654 | * The caller must hold @udev's device lock. |
1655 | */ |
1656 | void usb_disable_autosuspend(struct usb_device *udev) |
1657 | { |
1658 | pm_runtime_forbid(dev: &udev->dev); |
1659 | } |
1660 | EXPORT_SYMBOL_GPL(usb_disable_autosuspend); |
1661 | |
1662 | /** |
1663 | * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces |
1664 | * @udev: the usb_device to autosuspend |
1665 | * |
1666 | * This routine should be called when a core subsystem is finished using |
1667 | * @udev and wants to allow it to autosuspend. Examples would be when |
1668 | * @udev's device file in usbfs is closed or after a configuration change. |
1669 | * |
1670 | * @udev's usage counter is decremented; if it drops to 0 and all the |
1671 | * interfaces are inactive then a delayed autosuspend will be attempted. |
1672 | * The attempt may fail (see autosuspend_check()). |
1673 | * |
1674 | * The caller must hold @udev's device lock. |
1675 | * |
1676 | * This routine can run only in process context. |
1677 | */ |
1678 | void usb_autosuspend_device(struct usb_device *udev) |
1679 | { |
1680 | int status; |
1681 | |
1682 | usb_mark_last_busy(udev); |
1683 | status = pm_runtime_put_sync_autosuspend(dev: &udev->dev); |
1684 | dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n" , |
1685 | __func__, atomic_read(&udev->dev.power.usage_count), |
1686 | status); |
1687 | } |
1688 | |
1689 | /** |
1690 | * usb_autoresume_device - immediately autoresume a USB device and its interfaces |
1691 | * @udev: the usb_device to autoresume |
1692 | * |
1693 | * This routine should be called when a core subsystem wants to use @udev |
1694 | * and needs to guarantee that it is not suspended. No autosuspend will |
1695 | * occur until usb_autosuspend_device() is called. (Note that this will |
1696 | * not prevent suspend events originating in the PM core.) Examples would |
1697 | * be when @udev's device file in usbfs is opened or when a remote-wakeup |
1698 | * request is received. |
1699 | * |
1700 | * @udev's usage counter is incremented to prevent subsequent autosuspends. |
1701 | * However if the autoresume fails then the usage counter is re-decremented. |
1702 | * |
1703 | * The caller must hold @udev's device lock. |
1704 | * |
1705 | * This routine can run only in process context. |
1706 | * |
1707 | * Return: 0 on success. A negative error code otherwise. |
1708 | */ |
1709 | int usb_autoresume_device(struct usb_device *udev) |
1710 | { |
1711 | int status; |
1712 | |
1713 | status = pm_runtime_resume_and_get(dev: &udev->dev); |
1714 | dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n" , |
1715 | __func__, atomic_read(&udev->dev.power.usage_count), |
1716 | status); |
1717 | if (status > 0) |
1718 | status = 0; |
1719 | return status; |
1720 | } |
1721 | |
1722 | /** |
1723 | * usb_autopm_put_interface - decrement a USB interface's PM-usage counter |
1724 | * @intf: the usb_interface whose counter should be decremented |
1725 | * |
1726 | * This routine should be called by an interface driver when it is |
1727 | * finished using @intf and wants to allow it to autosuspend. A typical |
1728 | * example would be a character-device driver when its device file is |
1729 | * closed. |
1730 | * |
1731 | * The routine decrements @intf's usage counter. When the counter reaches |
1732 | * 0, a delayed autosuspend request for @intf's device is attempted. The |
1733 | * attempt may fail (see autosuspend_check()). |
1734 | * |
1735 | * This routine can run only in process context. |
1736 | */ |
1737 | void usb_autopm_put_interface(struct usb_interface *intf) |
1738 | { |
1739 | struct usb_device *udev = interface_to_usbdev(intf); |
1740 | int status; |
1741 | |
1742 | usb_mark_last_busy(udev); |
1743 | status = pm_runtime_put_sync(dev: &intf->dev); |
1744 | dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n" , |
1745 | __func__, atomic_read(&intf->dev.power.usage_count), |
1746 | status); |
1747 | } |
1748 | EXPORT_SYMBOL_GPL(usb_autopm_put_interface); |
1749 | |
1750 | /** |
1751 | * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter |
1752 | * @intf: the usb_interface whose counter should be decremented |
1753 | * |
1754 | * This routine does much the same thing as usb_autopm_put_interface(): |
1755 | * It decrements @intf's usage counter and schedules a delayed |
1756 | * autosuspend request if the counter is <= 0. The difference is that it |
1757 | * does not perform any synchronization; callers should hold a private |
1758 | * lock and handle all synchronization issues themselves. |
1759 | * |
1760 | * Typically a driver would call this routine during an URB's completion |
1761 | * handler, if no more URBs were pending. |
1762 | * |
1763 | * This routine can run in atomic context. |
1764 | */ |
1765 | void usb_autopm_put_interface_async(struct usb_interface *intf) |
1766 | { |
1767 | struct usb_device *udev = interface_to_usbdev(intf); |
1768 | int status; |
1769 | |
1770 | usb_mark_last_busy(udev); |
1771 | status = pm_runtime_put(dev: &intf->dev); |
1772 | dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n" , |
1773 | __func__, atomic_read(&intf->dev.power.usage_count), |
1774 | status); |
1775 | } |
1776 | EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async); |
1777 | |
1778 | /** |
1779 | * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter |
1780 | * @intf: the usb_interface whose counter should be decremented |
1781 | * |
1782 | * This routine decrements @intf's usage counter but does not carry out an |
1783 | * autosuspend. |
1784 | * |
1785 | * This routine can run in atomic context. |
1786 | */ |
1787 | void usb_autopm_put_interface_no_suspend(struct usb_interface *intf) |
1788 | { |
1789 | struct usb_device *udev = interface_to_usbdev(intf); |
1790 | |
1791 | usb_mark_last_busy(udev); |
1792 | pm_runtime_put_noidle(dev: &intf->dev); |
1793 | } |
1794 | EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend); |
1795 | |
1796 | /** |
1797 | * usb_autopm_get_interface - increment a USB interface's PM-usage counter |
1798 | * @intf: the usb_interface whose counter should be incremented |
1799 | * |
1800 | * This routine should be called by an interface driver when it wants to |
1801 | * use @intf and needs to guarantee that it is not suspended. In addition, |
1802 | * the routine prevents @intf from being autosuspended subsequently. (Note |
1803 | * that this will not prevent suspend events originating in the PM core.) |
1804 | * This prevention will persist until usb_autopm_put_interface() is called |
1805 | * or @intf is unbound. A typical example would be a character-device |
1806 | * driver when its device file is opened. |
1807 | * |
1808 | * @intf's usage counter is incremented to prevent subsequent autosuspends. |
1809 | * However if the autoresume fails then the counter is re-decremented. |
1810 | * |
1811 | * This routine can run only in process context. |
1812 | * |
1813 | * Return: 0 on success. |
1814 | */ |
1815 | int usb_autopm_get_interface(struct usb_interface *intf) |
1816 | { |
1817 | int status; |
1818 | |
1819 | status = pm_runtime_resume_and_get(dev: &intf->dev); |
1820 | dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n" , |
1821 | __func__, atomic_read(&intf->dev.power.usage_count), |
1822 | status); |
1823 | if (status > 0) |
1824 | status = 0; |
1825 | return status; |
1826 | } |
1827 | EXPORT_SYMBOL_GPL(usb_autopm_get_interface); |
1828 | |
1829 | /** |
1830 | * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter |
1831 | * @intf: the usb_interface whose counter should be incremented |
1832 | * |
1833 | * This routine does much the same thing as |
1834 | * usb_autopm_get_interface(): It increments @intf's usage counter and |
1835 | * queues an autoresume request if the device is suspended. The |
1836 | * differences are that it does not perform any synchronization (callers |
1837 | * should hold a private lock and handle all synchronization issues |
1838 | * themselves), and it does not autoresume the device directly (it only |
1839 | * queues a request). After a successful call, the device may not yet be |
1840 | * resumed. |
1841 | * |
1842 | * This routine can run in atomic context. |
1843 | * |
1844 | * Return: 0 on success. A negative error code otherwise. |
1845 | */ |
1846 | int usb_autopm_get_interface_async(struct usb_interface *intf) |
1847 | { |
1848 | int status; |
1849 | |
1850 | status = pm_runtime_get(dev: &intf->dev); |
1851 | if (status < 0 && status != -EINPROGRESS) |
1852 | pm_runtime_put_noidle(dev: &intf->dev); |
1853 | dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n" , |
1854 | __func__, atomic_read(&intf->dev.power.usage_count), |
1855 | status); |
1856 | if (status > 0 || status == -EINPROGRESS) |
1857 | status = 0; |
1858 | return status; |
1859 | } |
1860 | EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async); |
1861 | |
1862 | /** |
1863 | * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter |
1864 | * @intf: the usb_interface whose counter should be incremented |
1865 | * |
1866 | * This routine increments @intf's usage counter but does not carry out an |
1867 | * autoresume. |
1868 | * |
1869 | * This routine can run in atomic context. |
1870 | */ |
1871 | void usb_autopm_get_interface_no_resume(struct usb_interface *intf) |
1872 | { |
1873 | struct usb_device *udev = interface_to_usbdev(intf); |
1874 | |
1875 | usb_mark_last_busy(udev); |
1876 | pm_runtime_get_noresume(dev: &intf->dev); |
1877 | } |
1878 | EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume); |
1879 | |
1880 | /* Internal routine to check whether we may autosuspend a device. */ |
1881 | static int autosuspend_check(struct usb_device *udev) |
1882 | { |
1883 | int w, i; |
1884 | struct usb_interface *intf; |
1885 | |
1886 | if (udev->state == USB_STATE_NOTATTACHED) |
1887 | return -ENODEV; |
1888 | |
1889 | /* Fail if autosuspend is disabled, or any interfaces are in use, or |
1890 | * any interface drivers require remote wakeup but it isn't available. |
1891 | */ |
1892 | w = 0; |
1893 | if (udev->actconfig) { |
1894 | for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { |
1895 | intf = udev->actconfig->interface[i]; |
1896 | |
1897 | /* We don't need to check interfaces that are |
1898 | * disabled for runtime PM. Either they are unbound |
1899 | * or else their drivers don't support autosuspend |
1900 | * and so they are permanently active. |
1901 | */ |
1902 | if (intf->dev.power.disable_depth) |
1903 | continue; |
1904 | if (atomic_read(v: &intf->dev.power.usage_count) > 0) |
1905 | return -EBUSY; |
1906 | w |= intf->needs_remote_wakeup; |
1907 | |
1908 | /* Don't allow autosuspend if the device will need |
1909 | * a reset-resume and any of its interface drivers |
1910 | * doesn't include support or needs remote wakeup. |
1911 | */ |
1912 | if (udev->quirks & USB_QUIRK_RESET_RESUME) { |
1913 | struct usb_driver *driver; |
1914 | |
1915 | driver = to_usb_driver(intf->dev.driver); |
1916 | if (!driver->reset_resume || |
1917 | intf->needs_remote_wakeup) |
1918 | return -EOPNOTSUPP; |
1919 | } |
1920 | } |
1921 | } |
1922 | if (w && !device_can_wakeup(dev: &udev->dev)) { |
1923 | dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n" ); |
1924 | return -EOPNOTSUPP; |
1925 | } |
1926 | |
1927 | /* |
1928 | * If the device is a direct child of the root hub and the HCD |
1929 | * doesn't handle wakeup requests, don't allow autosuspend when |
1930 | * wakeup is needed. |
1931 | */ |
1932 | if (w && udev->parent == udev->bus->root_hub && |
1933 | bus_to_hcd(bus: udev->bus)->cant_recv_wakeups) { |
1934 | dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\n" ); |
1935 | return -EOPNOTSUPP; |
1936 | } |
1937 | |
1938 | udev->do_remote_wakeup = w; |
1939 | return 0; |
1940 | } |
1941 | |
1942 | int usb_runtime_suspend(struct device *dev) |
1943 | { |
1944 | struct usb_device *udev = to_usb_device(dev); |
1945 | int status; |
1946 | |
1947 | /* A USB device can be suspended if it passes the various autosuspend |
1948 | * checks. Runtime suspend for a USB device means suspending all the |
1949 | * interfaces and then the device itself. |
1950 | */ |
1951 | if (autosuspend_check(udev) != 0) |
1952 | return -EAGAIN; |
1953 | |
1954 | status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND); |
1955 | |
1956 | /* Allow a retry if autosuspend failed temporarily */ |
1957 | if (status == -EAGAIN || status == -EBUSY) |
1958 | usb_mark_last_busy(udev); |
1959 | |
1960 | /* |
1961 | * The PM core reacts badly unless the return code is 0, |
1962 | * -EAGAIN, or -EBUSY, so always return -EBUSY on an error |
1963 | * (except for root hubs, because they don't suspend through |
1964 | * an upstream port like other USB devices). |
1965 | */ |
1966 | if (status != 0 && udev->parent) |
1967 | return -EBUSY; |
1968 | return status; |
1969 | } |
1970 | |
1971 | int usb_runtime_resume(struct device *dev) |
1972 | { |
1973 | struct usb_device *udev = to_usb_device(dev); |
1974 | int status; |
1975 | |
1976 | /* Runtime resume for a USB device means resuming both the device |
1977 | * and all its interfaces. |
1978 | */ |
1979 | status = usb_resume_both(udev, PMSG_AUTO_RESUME); |
1980 | return status; |
1981 | } |
1982 | |
1983 | int usb_runtime_idle(struct device *dev) |
1984 | { |
1985 | struct usb_device *udev = to_usb_device(dev); |
1986 | |
1987 | /* An idle USB device can be suspended if it passes the various |
1988 | * autosuspend checks. |
1989 | */ |
1990 | if (autosuspend_check(udev) == 0) |
1991 | pm_runtime_autosuspend(dev); |
1992 | /* Tell the core not to suspend it, though. */ |
1993 | return -EBUSY; |
1994 | } |
1995 | |
1996 | static int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable) |
1997 | { |
1998 | struct usb_hcd *hcd = bus_to_hcd(bus: udev->bus); |
1999 | int ret = -EPERM; |
2000 | |
2001 | if (hcd->driver->set_usb2_hw_lpm) { |
2002 | ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable); |
2003 | if (!ret) |
2004 | udev->usb2_hw_lpm_enabled = enable; |
2005 | } |
2006 | |
2007 | return ret; |
2008 | } |
2009 | |
2010 | int usb_enable_usb2_hardware_lpm(struct usb_device *udev) |
2011 | { |
2012 | if (!udev->usb2_hw_lpm_capable || |
2013 | !udev->usb2_hw_lpm_allowed || |
2014 | udev->usb2_hw_lpm_enabled) |
2015 | return 0; |
2016 | |
2017 | return usb_set_usb2_hardware_lpm(udev, enable: 1); |
2018 | } |
2019 | |
2020 | int usb_disable_usb2_hardware_lpm(struct usb_device *udev) |
2021 | { |
2022 | if (!udev->usb2_hw_lpm_enabled) |
2023 | return 0; |
2024 | |
2025 | return usb_set_usb2_hardware_lpm(udev, enable: 0); |
2026 | } |
2027 | |
2028 | #endif /* CONFIG_PM */ |
2029 | |
2030 | const struct bus_type usb_bus_type = { |
2031 | .name = "usb" , |
2032 | .match = usb_device_match, |
2033 | .uevent = usb_uevent, |
2034 | .need_parent_lock = true, |
2035 | }; |
2036 | |