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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 <[email protected]>
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 */
42ssize_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_obj(*dynid);
61 if (!dynid)
62 return -ENOMEM;
63
64 INIT_LIST_HEAD(&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 mutex_lock(&usb_dynids_lock);
99 list_add_tail(&dynid->node, &dynids->list);
100 mutex_unlock(&usb_dynids_lock);
101
102 retval = driver_attach(driver);
103
104 if (retval)
105 return retval;
106 return count;
107
108fail:
109 kfree(dynid);
110 return retval;
111}
112EXPORT_SYMBOL_GPL(usb_store_new_id);
113
114ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf)
115{
116 struct usb_dynid *dynid;
117 size_t count = 0;
118
119 guard(mutex)(&usb_dynids_lock);
120 list_for_each_entry(dynid, &dynids->list, node)
121 if (dynid->id.bInterfaceClass != 0)
122 count += sysfs_emit_at(buf, count, "%04x %04x %02x\n",
123 dynid->id.idVendor, dynid->id.idProduct,
124 dynid->id.bInterfaceClass);
125 else
126 count += sysfs_emit_at(buf, count, "%04x %04x\n",
127 dynid->id.idVendor, dynid->id.idProduct);
128 return count;
129}
130EXPORT_SYMBOL_GPL(usb_show_dynids);
131
132static ssize_t new_id_show(struct device_driver *driver, char *buf)
133{
134 struct usb_driver *usb_drv = to_usb_driver(driver);
135
136 return usb_show_dynids(&usb_drv->dynids, buf);
137}
138
139static ssize_t new_id_store(struct device_driver *driver,
140 const char *buf, size_t count)
141{
142 struct usb_driver *usb_drv = to_usb_driver(driver);
143
144 return usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, driver, buf, count);
145}
146static DRIVER_ATTR_RW(new_id);
147
148/*
149 * Remove a USB device ID from this driver
150 */
151static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
152 size_t count)
153{
154 struct usb_dynid *dynid, *n;
155 struct usb_driver *usb_driver = to_usb_driver(driver);
156 u32 idVendor;
157 u32 idProduct;
158 int fields;
159
160 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
161 if (fields < 2)
162 return -EINVAL;
163
164 guard(mutex)(&usb_dynids_lock);
165 list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) {
166 struct usb_device_id *id = &dynid->id;
167
168 if ((id->idVendor == idVendor) &&
169 (id->idProduct == idProduct)) {
170 list_del(&dynid->node);
171 kfree(dynid);
172 break;
173 }
174 }
175 return count;
176}
177
178static ssize_t remove_id_show(struct device_driver *driver, char *buf)
179{
180 return new_id_show(driver, buf);
181}
182static DRIVER_ATTR_RW(remove_id);
183
184static 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(&usb_drv->driver,
193 &driver_attr_new_id);
194 if (error == 0) {
195 error = driver_create_file(&usb_drv->driver,
196 &driver_attr_remove_id);
197 if (error)
198 driver_remove_file(&usb_drv->driver,
199 &driver_attr_new_id);
200 }
201 }
202exit:
203 return error;
204}
205
206static 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(&usb_drv->driver,
213 &driver_attr_remove_id);
214 driver_remove_file(&usb_drv->driver,
215 &driver_attr_new_id);
216 }
217}
218
219static void usb_free_dynids(struct usb_driver *usb_drv)
220{
221 struct usb_dynid *dynid, *n;
222
223 guard(mutex)(&usb_dynids_lock);
224 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
225 list_del(&dynid->node);
226 kfree(dynid);
227 }
228}
229
230static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
231 const struct usb_driver *drv,
232 struct usb_device_id *id_copy)
233{
234 struct usb_dynid *dynid;
235
236 guard(mutex)(&usb_dynids_lock);
237 list_for_each_entry(dynid, &drv->dynids.list, node) {
238 if (usb_match_one_id(intf, &dynid->id)) {
239 *id_copy = dynid->id;
240 return id_copy;
241 }
242 }
243 return NULL;
244}
245
246
247/* called from driver core with dev locked */
248static int usb_probe_device(struct device *dev)
249{
250 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
251 struct usb_device *udev = to_usb_device(dev);
252 int error = 0;
253
254 dev_dbg(dev, "%s\n", __func__);
255
256 /* TODO: Add real matching code */
257
258 /* The device should always appear to be in use
259 * unless the driver supports autosuspend.
260 */
261 if (!udriver->supports_autosuspend)
262 error = usb_autoresume_device(udev);
263 if (error)
264 return error;
265
266 if (udriver->generic_subclass)
267 error = usb_generic_driver_probe(udev);
268 if (error)
269 return error;
270
271 /* Probe the USB device with the driver in hand, but only
272 * defer to a generic driver in case the current USB
273 * device driver has an id_table or a match function; i.e.,
274 * when the device driver was explicitly matched against
275 * a device.
276 *
277 * If the device driver does not have either of these,
278 * then we assume that it can bind to any device and is
279 * not truly a more specialized/non-generic driver, so a
280 * return value of -ENODEV should not force the device
281 * to be handled by the generic USB driver, as there
282 * can still be another, more specialized, device driver.
283 *
284 * This accommodates the usbip driver.
285 *
286 * TODO: What if, in the future, there are multiple
287 * specialized USB device drivers for a particular device?
288 * In such cases, there is a need to try all matching
289 * specialised device drivers prior to setting the
290 * use_generic_driver bit.
291 */
292 if (udriver->probe)
293 error = udriver->probe(udev);
294 else if (!udriver->generic_subclass)
295 error = -EINVAL;
296 if (error == -ENODEV && udriver != &usb_generic_driver &&
297 (udriver->id_table || udriver->match)) {
298 udev->use_generic_driver = 1;
299 return -EPROBE_DEFER;
300 }
301 return error;
302}
303
304/* called from driver core with dev locked */
305static int usb_unbind_device(struct device *dev)
306{
307 struct usb_device *udev = to_usb_device(dev);
308 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
309
310 if (udriver->disconnect)
311 udriver->disconnect(udev);
312 if (udriver->generic_subclass)
313 usb_generic_driver_disconnect(udev);
314 if (!udriver->supports_autosuspend)
315 usb_autosuspend_device(udev);
316 return 0;
317}
318
319/* called from driver core with dev locked */
320static int usb_probe_interface(struct device *dev)
321{
322 struct usb_driver *driver = to_usb_driver(dev->driver);
323 struct usb_interface *intf = to_usb_interface(dev);
324 struct usb_device *udev = interface_to_usbdev(intf);
325 const struct usb_device_id *id;
326 struct usb_device_id id_copy;
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_info(&intf->dev, "Device is not authorized for usage\n");
339 return error;
340 } else if (intf->authorized == 0) {
341 dev_info(&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, driver, &id_copy);
347 if (!id)
348 id = usb_match_id(intf, 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, 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(udev, intf->altsetting[0].
393 desc.bInterfaceNumber, 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 */
431static 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(udev, intf, 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, sizeof(void *),
470 GFP_KERNEL);
471 if (!eps)
472 break;
473 }
474 eps[j++] = ep;
475 }
476 if (j) {
477 usb_free_streams(intf, eps, j, GFP_KERNEL);
478 kfree(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(udev, intf, false);
492 } else if (!error && !intf->dev.power.is_prepared) {
493 r = usb_set_interface(udev, intf->altsetting[0].
494 desc.bInterfaceNumber, 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
520static void usb_shutdown_interface(struct device *dev)
521{
522 struct usb_interface *intf = to_usb_interface(dev);
523 struct usb_driver *driver;
524
525 if (!dev->driver)
526 return;
527
528 driver = to_usb_driver(dev->driver);
529 if (driver->shutdown)
530 driver->shutdown(intf);
531}
532
533/**
534 * usb_driver_claim_interface - bind a driver to an interface
535 * @driver: the driver to be bound
536 * @iface: the interface to which it will be bound; must be in the
537 * usb device's active configuration
538 * @data: driver data associated with that interface
539 *
540 * This is used by usb device drivers that need to claim more than one
541 * interface on a device when probing (audio and acm are current examples).
542 * No device driver should directly modify internal usb_interface or
543 * usb_device structure members.
544 *
545 * Callers must own the device lock, so driver probe() entries don't need
546 * extra locking, but other call contexts may need to explicitly claim that
547 * lock.
548 *
549 * Return: 0 on success.
550 */
551int usb_driver_claim_interface(struct usb_driver *driver,
552 struct usb_interface *iface, void *data)
553{
554 struct device *dev;
555 int retval = 0;
556
557 if (!iface)
558 return -ENODEV;
559
560 dev = &iface->dev;
561 if (dev->driver)
562 return -EBUSY;
563
564 /* reject claim if interface is not authorized */
565 if (!iface->authorized)
566 return -ENODEV;
567
568 dev->driver = &driver->driver;
569 usb_set_intfdata(iface, data);
570 iface->needs_binding = 0;
571
572 iface->condition = USB_INTERFACE_BOUND;
573
574 /* Claimed interfaces are initially inactive (suspended) and
575 * runtime-PM-enabled, but only if the driver has autosuspend
576 * support. Otherwise they are marked active, to prevent the
577 * device from being autosuspended, but left disabled. In either
578 * case they are sensitive to their children's power states.
579 */
580 pm_suspend_ignore_children(dev, false);
581 if (driver->supports_autosuspend)
582 pm_runtime_enable(dev);
583 else
584 pm_runtime_set_active(dev);
585
586 /* if interface was already added, bind now; else let
587 * the future device_add() bind it, bypassing probe()
588 */
589 if (device_is_registered(dev))
590 retval = device_bind_driver(dev);
591
592 if (retval) {
593 dev->driver = NULL;
594 usb_set_intfdata(iface, NULL);
595 iface->needs_remote_wakeup = 0;
596 iface->condition = USB_INTERFACE_UNBOUND;
597
598 /*
599 * Unbound interfaces are always runtime-PM-disabled
600 * and runtime-PM-suspended
601 */
602 if (driver->supports_autosuspend)
603 pm_runtime_disable(dev);
604 pm_runtime_set_suspended(dev);
605 }
606
607 return retval;
608}
609EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
610
611/**
612 * usb_driver_release_interface - unbind a driver from an interface
613 * @driver: the driver to be unbound
614 * @iface: the interface from which it will be unbound
615 *
616 * This can be used by drivers to release an interface without waiting
617 * for their disconnect() methods to be called. In typical cases this
618 * also causes the driver disconnect() method to be called.
619 *
620 * This call is synchronous, and may not be used in an interrupt context.
621 * Callers must own the device lock, so driver disconnect() entries don't
622 * need extra locking, but other call contexts may need to explicitly claim
623 * that lock.
624 */
625void usb_driver_release_interface(struct usb_driver *driver,
626 struct usb_interface *iface)
627{
628 struct device *dev = &iface->dev;
629
630 /* this should never happen, don't release something that's not ours */
631 if (!dev->driver || dev->driver != &driver->driver)
632 return;
633
634 /* don't release from within disconnect() */
635 if (iface->condition != USB_INTERFACE_BOUND)
636 return;
637 iface->condition = USB_INTERFACE_UNBINDING;
638
639 /* Release via the driver core only if the interface
640 * has already been registered
641 */
642 if (device_is_registered(dev)) {
643 device_release_driver(dev);
644 } else {
645 device_lock(dev);
646 usb_unbind_interface(dev);
647 dev->driver = NULL;
648 device_unlock(dev);
649 }
650}
651EXPORT_SYMBOL_GPL(usb_driver_release_interface);
652
653/* returns 0 if no match, 1 if match */
654int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
655{
656 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
657 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
658 return 0;
659
660 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
661 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
662 return 0;
663
664 /* No need to test id->bcdDevice_lo != 0, since 0 is never
665 greater than any unsigned number. */
666 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
667 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
668 return 0;
669
670 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
671 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
672 return 0;
673
674 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
675 (id->bDeviceClass != dev->descriptor.bDeviceClass))
676 return 0;
677
678 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
679 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
680 return 0;
681
682 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
683 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
684 return 0;
685
686 return 1;
687}
688
689/* returns 0 if no match, 1 if match */
690int usb_match_one_id_intf(struct usb_device *dev,
691 struct usb_host_interface *intf,
692 const struct usb_device_id *id)
693{
694 /* The interface class, subclass, protocol and number should never be
695 * checked for a match if the device class is Vendor Specific,
696 * unless the match record specifies the Vendor ID. */
697 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
698 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
699 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
700 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
701 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
702 USB_DEVICE_ID_MATCH_INT_NUMBER)))
703 return 0;
704
705 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
706 (id->bInterfaceClass != intf->desc.bInterfaceClass))
707 return 0;
708
709 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
710 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
711 return 0;
712
713 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
714 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
715 return 0;
716
717 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
718 (id->bInterfaceNumber != intf->desc.bInterfaceNumber))
719 return 0;
720
721 return 1;
722}
723
724/* returns 0 if no match, 1 if match */
725int usb_match_one_id(struct usb_interface *interface,
726 const struct usb_device_id *id)
727{
728 struct usb_host_interface *intf;
729 struct usb_device *dev;
730
731 /* proc_connectinfo in devio.c may call us with id == NULL. */
732 if (id == NULL)
733 return 0;
734
735 intf = interface->cur_altsetting;
736 dev = interface_to_usbdev(interface);
737
738 if (!usb_match_device(dev, id))
739 return 0;
740
741 return usb_match_one_id_intf(dev, intf, id);
742}
743EXPORT_SYMBOL_GPL(usb_match_one_id);
744
745/**
746 * usb_match_id - find first usb_device_id matching device or interface
747 * @interface: the interface of interest
748 * @id: array of usb_device_id structures, terminated by zero entry
749 *
750 * usb_match_id searches an array of usb_device_id's and returns
751 * the first one matching the device or interface, or null.
752 * This is used when binding (or rebinding) a driver to an interface.
753 * Most USB device drivers will use this indirectly, through the usb core,
754 * but some layered driver frameworks use it directly.
755 * These device tables are exported with MODULE_DEVICE_TABLE, through
756 * modutils, to support the driver loading functionality of USB hotplugging.
757 *
758 * Return: The first matching usb_device_id, or %NULL.
759 *
760 * What Matches:
761 *
762 * The "match_flags" element in a usb_device_id controls which
763 * members are used. If the corresponding bit is set, the
764 * value in the device_id must match its corresponding member
765 * in the device or interface descriptor, or else the device_id
766 * does not match.
767 *
768 * "driver_info" is normally used only by device drivers,
769 * but you can create a wildcard "matches anything" usb_device_id
770 * as a driver's "modules.usbmap" entry if you provide an id with
771 * only a nonzero "driver_info" field. If you do this, the USB device
772 * driver's probe() routine should use additional intelligence to
773 * decide whether to bind to the specified interface.
774 *
775 * What Makes Good usb_device_id Tables:
776 *
777 * The match algorithm is very simple, so that intelligence in
778 * driver selection must come from smart driver id records.
779 * Unless you have good reasons to use another selection policy,
780 * provide match elements only in related groups, and order match
781 * specifiers from specific to general. Use the macros provided
782 * for that purpose if you can.
783 *
784 * The most specific match specifiers use device descriptor
785 * data. These are commonly used with product-specific matches;
786 * the USB_DEVICE macro lets you provide vendor and product IDs,
787 * and you can also match against ranges of product revisions.
788 * These are widely used for devices with application or vendor
789 * specific bDeviceClass values.
790 *
791 * Matches based on device class/subclass/protocol specifications
792 * are slightly more general; use the USB_DEVICE_INFO macro, or
793 * its siblings. These are used with single-function devices
794 * where bDeviceClass doesn't specify that each interface has
795 * its own class.
796 *
797 * Matches based on interface class/subclass/protocol are the
798 * most general; they let drivers bind to any interface on a
799 * multiple-function device. Use the USB_INTERFACE_INFO
800 * macro, or its siblings, to match class-per-interface style
801 * devices (as recorded in bInterfaceClass).
802 *
803 * Note that an entry created by USB_INTERFACE_INFO won't match
804 * any interface if the device class is set to Vendor-Specific.
805 * This is deliberate; according to the USB spec the meanings of
806 * the interface class/subclass/protocol for these devices are also
807 * vendor-specific, and hence matching against a standard product
808 * class wouldn't work anyway. If you really want to use an
809 * interface-based match for such a device, create a match record
810 * that also specifies the vendor ID. (Unforunately there isn't a
811 * standard macro for creating records like this.)
812 *
813 * Within those groups, remember that not all combinations are
814 * meaningful. For example, don't give a product version range
815 * without vendor and product IDs; or specify a protocol without
816 * its associated class and subclass.
817 */
818const struct usb_device_id *usb_match_id(struct usb_interface *interface,
819 const struct usb_device_id *id)
820{
821 /* proc_connectinfo in devio.c may call us with id == NULL. */
822 if (id == NULL)
823 return NULL;
824
825 /* It is important to check that id->driver_info is nonzero,
826 since an entry that is all zeroes except for a nonzero
827 id->driver_info is the way to create an entry that
828 indicates that the driver want to examine every
829 device and interface. */
830 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
831 id->bInterfaceClass || id->driver_info; id++) {
832 if (usb_match_one_id(interface, id))
833 return id;
834 }
835
836 return NULL;
837}
838EXPORT_SYMBOL_GPL(usb_match_id);
839
840const struct usb_device_id *usb_device_match_id(struct usb_device *udev,
841 const struct usb_device_id *id)
842{
843 if (!id)
844 return NULL;
845
846 for (; id->idVendor || id->idProduct ; id++) {
847 if (usb_match_device(udev, id))
848 return id;
849 }
850
851 return NULL;
852}
853EXPORT_SYMBOL_GPL(usb_device_match_id);
854
855bool usb_driver_applicable(struct usb_device *udev,
856 const struct usb_device_driver *udrv)
857{
858 if (udrv->id_table && udrv->match)
859 return usb_device_match_id(udev, udrv->id_table) != NULL &&
860 udrv->match(udev);
861
862 if (udrv->id_table)
863 return usb_device_match_id(udev, udrv->id_table) != NULL;
864
865 if (udrv->match)
866 return udrv->match(udev);
867
868 return false;
869}
870
871static int usb_device_match(struct device *dev, const struct device_driver *drv)
872{
873 /* devices and interfaces are handled separately */
874 if (is_usb_device(dev)) {
875 struct usb_device *udev;
876 const struct usb_device_driver *udrv;
877
878 /* interface drivers never match devices */
879 if (!is_usb_device_driver(drv))
880 return 0;
881
882 udev = to_usb_device(dev);
883 udrv = to_usb_device_driver(drv);
884
885 /* If the device driver under consideration does not have a
886 * id_table or a match function, then let the driver's probe
887 * function decide.
888 */
889 if (!udrv->id_table && !udrv->match)
890 return 1;
891
892 return usb_driver_applicable(udev, udrv);
893
894 } else if (is_usb_interface(dev)) {
895 struct usb_interface *intf;
896 const struct usb_driver *usb_drv;
897 const struct usb_device_id *id;
898 struct usb_device_id id_copy;
899
900 /* device drivers never match interfaces */
901 if (is_usb_device_driver(drv))
902 return 0;
903
904 intf = to_usb_interface(dev);
905 usb_drv = to_usb_driver(drv);
906
907 id = usb_match_id(intf, usb_drv->id_table);
908 if (id)
909 return 1;
910
911 id = usb_match_dynamic_id(intf, usb_drv, &id_copy);
912 if (id)
913 return 1;
914 }
915
916 return 0;
917}
918
919static int usb_uevent(const struct device *dev, struct kobj_uevent_env *env)
920{
921 const struct usb_device *usb_dev;
922
923 if (is_usb_device(dev)) {
924 usb_dev = to_usb_device(dev);
925 } else if (is_usb_interface(dev)) {
926 const struct usb_interface *intf = to_usb_interface(dev);
927
928 usb_dev = interface_to_usbdev(intf);
929 } else {
930 return 0;
931 }
932
933 if (usb_dev->devnum < 0) {
934 /* driver is often null here; dev_dbg() would oops */
935 pr_debug("usb %s: already deleted?\n", dev_name(dev));
936 return -ENODEV;
937 }
938 if (!usb_dev->bus) {
939 pr_debug("usb %s: bus removed?\n", dev_name(dev));
940 return -ENODEV;
941 }
942
943 /* per-device configurations are common */
944 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
945 le16_to_cpu(usb_dev->descriptor.idVendor),
946 le16_to_cpu(usb_dev->descriptor.idProduct),
947 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
948 return -ENOMEM;
949
950 /* class-based driver binding models */
951 if (add_uevent_var(env, "TYPE=%d/%d/%d",
952 usb_dev->descriptor.bDeviceClass,
953 usb_dev->descriptor.bDeviceSubClass,
954 usb_dev->descriptor.bDeviceProtocol))
955 return -ENOMEM;
956
957 return 0;
958}
959
960static int __usb_bus_reprobe_drivers(struct device *dev, void *data)
961{
962 struct usb_device_driver *new_udriver = data;
963 struct usb_device *udev;
964 int ret;
965
966 /* Don't reprobe if current driver isn't usb_generic_driver */
967 if (dev->driver != &usb_generic_driver.driver)
968 return 0;
969
970 udev = to_usb_device(dev);
971 if (!usb_driver_applicable(udev, new_udriver))
972 return 0;
973
974 ret = device_reprobe(dev);
975 if (ret && ret != -EPROBE_DEFER)
976 dev_err(dev, "Failed to reprobe device (error %d)\n", ret);
977
978 return 0;
979}
980
981bool is_usb_device_driver(const struct device_driver *drv)
982{
983 return drv->probe == usb_probe_device;
984}
985
986/**
987 * usb_register_device_driver - register a USB device (not interface) driver
988 * @new_udriver: USB operations for the device driver
989 * @owner: module owner of this driver.
990 *
991 * Registers a USB device driver with the USB core. The list of
992 * unattached devices will be rescanned whenever a new driver is
993 * added, allowing the new driver to attach to any recognized devices.
994 *
995 * Return: A negative error code on failure and 0 on success.
996 */
997int usb_register_device_driver(struct usb_device_driver *new_udriver,
998 struct module *owner)
999{
1000 int retval = 0;
1001
1002 if (usb_disabled())
1003 return -ENODEV;
1004
1005 new_udriver->driver.name = new_udriver->name;
1006 new_udriver->driver.bus = &usb_bus_type;
1007 new_udriver->driver.probe = usb_probe_device;
1008 new_udriver->driver.remove = usb_unbind_device;
1009 new_udriver->driver.owner = owner;
1010 new_udriver->driver.dev_groups = new_udriver->dev_groups;
1011
1012 retval = driver_register(&new_udriver->driver);
1013
1014 if (!retval) {
1015 pr_info("%s: registered new device driver %s\n",
1016 usbcore_name, new_udriver->name);
1017 /*
1018 * Check whether any device could be better served with
1019 * this new driver
1020 */
1021 bus_for_each_dev(&usb_bus_type, NULL, new_udriver,
1022 __usb_bus_reprobe_drivers);
1023 } else {
1024 pr_err("%s: error %d registering device driver %s\n",
1025 usbcore_name, retval, new_udriver->name);
1026 }
1027
1028 return retval;
1029}
1030EXPORT_SYMBOL_GPL(usb_register_device_driver);
1031
1032/**
1033 * usb_deregister_device_driver - unregister a USB device (not interface) driver
1034 * @udriver: USB operations of the device driver to unregister
1035 * Context: must be able to sleep
1036 *
1037 * Unlinks the specified driver from the internal USB driver list.
1038 */
1039void usb_deregister_device_driver(struct usb_device_driver *udriver)
1040{
1041 pr_info("%s: deregistering device driver %s\n",
1042 usbcore_name, udriver->name);
1043
1044 driver_unregister(&udriver->driver);
1045}
1046EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
1047
1048/**
1049 * usb_register_driver - register a USB interface driver
1050 * @new_driver: USB operations for the interface driver
1051 * @owner: module owner of this driver.
1052 * @mod_name: module name string
1053 *
1054 * Registers a USB interface driver with the USB core. The list of
1055 * unattached interfaces will be rescanned whenever a new driver is
1056 * added, allowing the new driver to attach to any recognized interfaces.
1057 *
1058 * Return: A negative error code on failure and 0 on success.
1059 *
1060 * NOTE: if you want your driver to use the USB major number, you must call
1061 * usb_register_dev() to enable that functionality. This function no longer
1062 * takes care of that.
1063 */
1064int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
1065 const char *mod_name)
1066{
1067 int retval = 0;
1068
1069 if (usb_disabled())
1070 return -ENODEV;
1071
1072 new_driver->driver.name = new_driver->name;
1073 new_driver->driver.bus = &usb_bus_type;
1074 new_driver->driver.probe = usb_probe_interface;
1075 new_driver->driver.remove = usb_unbind_interface;
1076 new_driver->driver.shutdown = usb_shutdown_interface;
1077 new_driver->driver.owner = owner;
1078 new_driver->driver.mod_name = mod_name;
1079 new_driver->driver.dev_groups = new_driver->dev_groups;
1080 INIT_LIST_HEAD(&new_driver->dynids.list);
1081
1082 retval = driver_register(&new_driver->driver);
1083 if (retval)
1084 goto out;
1085
1086 retval = usb_create_newid_files(new_driver);
1087 if (retval)
1088 goto out_newid;
1089
1090 pr_info("%s: registered new interface driver %s\n",
1091 usbcore_name, new_driver->name);
1092
1093 return 0;
1094
1095out_newid:
1096 driver_unregister(&new_driver->driver);
1097out:
1098 pr_err("%s: error %d registering interface driver %s\n",
1099 usbcore_name, retval, new_driver->name);
1100 return retval;
1101}
1102EXPORT_SYMBOL_GPL(usb_register_driver);
1103
1104/**
1105 * usb_deregister - unregister a USB interface driver
1106 * @driver: USB operations of the interface driver to unregister
1107 * Context: must be able to sleep
1108 *
1109 * Unlinks the specified driver from the internal USB driver list.
1110 *
1111 * NOTE: If you called usb_register_dev(), you still need to call
1112 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
1113 * this * call will no longer do it for you.
1114 */
1115void usb_deregister(struct usb_driver *driver)
1116{
1117 pr_info("%s: deregistering interface driver %s\n",
1118 usbcore_name, driver->name);
1119
1120 usb_remove_newid_files(driver);
1121 driver_unregister(&driver->driver);
1122 usb_free_dynids(driver);
1123}
1124EXPORT_SYMBOL_GPL(usb_deregister);
1125
1126/* Forced unbinding of a USB interface driver, either because
1127 * it doesn't support pre_reset/post_reset/reset_resume or
1128 * because it doesn't support suspend/resume.
1129 *
1130 * The caller must hold @intf's device's lock, but not @intf's lock.
1131 */
1132void usb_forced_unbind_intf(struct usb_interface *intf)
1133{
1134 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
1135
1136 dev_dbg(&intf->dev, "forced unbind\n");
1137 usb_driver_release_interface(driver, intf);
1138
1139 /* Mark the interface for later rebinding */
1140 intf->needs_binding = 1;
1141}
1142
1143/*
1144 * Unbind drivers for @udev's marked interfaces. These interfaces have
1145 * the needs_binding flag set, for example by usb_resume_interface().
1146 *
1147 * The caller must hold @udev's device lock.
1148 */
1149static void unbind_marked_interfaces(struct usb_device *udev)
1150{
1151 struct usb_host_config *config;
1152 int i;
1153 struct usb_interface *intf;
1154
1155 config = udev->actconfig;
1156 if (config) {
1157 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1158 intf = config->interface[i];
1159 if (intf->dev.driver && intf->needs_binding)
1160 usb_forced_unbind_intf(intf);
1161 }
1162 }
1163}
1164
1165/* Delayed forced unbinding of a USB interface driver and scan
1166 * for rebinding.
1167 *
1168 * The caller must hold @intf's device's lock, but not @intf's lock.
1169 *
1170 * Note: Rebinds will be skipped if a system sleep transition is in
1171 * progress and the PM "complete" callback hasn't occurred yet.
1172 */
1173static void usb_rebind_intf(struct usb_interface *intf)
1174{
1175 int rc;
1176
1177 /* Delayed unbind of an existing driver */
1178 if (intf->dev.driver)
1179 usb_forced_unbind_intf(intf);
1180
1181 /* Try to rebind the interface */
1182 if (!intf->dev.power.is_prepared) {
1183 intf->needs_binding = 0;
1184 rc = device_attach(&intf->dev);
1185 if (rc < 0 && rc != -EPROBE_DEFER)
1186 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
1187 }
1188}
1189
1190/*
1191 * Rebind drivers to @udev's marked interfaces. These interfaces have
1192 * the needs_binding flag set.
1193 *
1194 * The caller must hold @udev's device lock.
1195 */
1196static void rebind_marked_interfaces(struct usb_device *udev)
1197{
1198 struct usb_host_config *config;
1199 int i;
1200 struct usb_interface *intf;
1201
1202 config = udev->actconfig;
1203 if (config) {
1204 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1205 intf = config->interface[i];
1206 if (intf->needs_binding)
1207 usb_rebind_intf(intf);
1208 }
1209 }
1210}
1211
1212/*
1213 * Unbind all of @udev's marked interfaces and then rebind all of them.
1214 * This ordering is necessary because some drivers claim several interfaces
1215 * when they are first probed.
1216 *
1217 * The caller must hold @udev's device lock.
1218 */
1219void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev)
1220{
1221 unbind_marked_interfaces(udev);
1222 rebind_marked_interfaces(udev);
1223}
1224
1225#ifdef CONFIG_PM
1226
1227/* Unbind drivers for @udev's interfaces that don't support suspend/resume
1228 * There is no check for reset_resume here because it can be determined
1229 * only during resume whether reset_resume is needed.
1230 *
1231 * The caller must hold @udev's device lock.
1232 */
1233static void unbind_no_pm_drivers_interfaces(struct usb_device *udev)
1234{
1235 struct usb_host_config *config;
1236 int i;
1237 struct usb_interface *intf;
1238 struct usb_driver *drv;
1239
1240 config = udev->actconfig;
1241 if (config) {
1242 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1243 intf = config->interface[i];
1244
1245 if (intf->dev.driver) {
1246 drv = to_usb_driver(intf->dev.driver);
1247 if (!drv->suspend || !drv->resume)
1248 usb_forced_unbind_intf(intf);
1249 }
1250 }
1251 }
1252}
1253
1254static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
1255{
1256 struct usb_device_driver *udriver;
1257 int status = 0;
1258
1259 if (udev->state == USB_STATE_NOTATTACHED ||
1260 udev->state == USB_STATE_SUSPENDED)
1261 goto done;
1262
1263 /* For devices that don't have a driver, we do a generic suspend. */
1264 if (udev->dev.driver)
1265 udriver = to_usb_device_driver(udev->dev.driver);
1266 else {
1267 udev->do_remote_wakeup = 0;
1268 udriver = &usb_generic_driver;
1269 }
1270 if (udriver->suspend)
1271 status = udriver->suspend(udev, msg);
1272 if (status == 0 && udriver->generic_subclass)
1273 status = usb_generic_driver_suspend(udev, msg);
1274
1275 done:
1276 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1277 return status;
1278}
1279
1280static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1281{
1282 struct usb_device_driver *udriver;
1283 int status = 0;
1284
1285 if (udev->state == USB_STATE_NOTATTACHED)
1286 goto done;
1287
1288 /* Can't resume it if it doesn't have a driver. */
1289 if (udev->dev.driver == NULL) {
1290 status = -ENOTCONN;
1291 goto done;
1292 }
1293
1294 /* Non-root devices on a full/low-speed bus must wait for their
1295 * companion high-speed root hub, in case a handoff is needed.
1296 */
1297 if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion)
1298 device_pm_wait_for_dev(&udev->dev,
1299 &udev->bus->hs_companion->root_hub->dev);
1300
1301 if (udev->quirks & USB_QUIRK_RESET_RESUME)
1302 udev->reset_resume = 1;
1303
1304 udriver = to_usb_device_driver(udev->dev.driver);
1305 if (udriver->generic_subclass)
1306 status = usb_generic_driver_resume(udev, msg);
1307 if (status == 0 && udriver->resume)
1308 status = udriver->resume(udev, msg);
1309
1310 done:
1311 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1312 return status;
1313}
1314
1315static int usb_suspend_interface(struct usb_device *udev,
1316 struct usb_interface *intf, pm_message_t msg)
1317{
1318 struct usb_driver *driver;
1319 int status = 0;
1320
1321 if (udev->state == USB_STATE_NOTATTACHED ||
1322 intf->condition == USB_INTERFACE_UNBOUND)
1323 goto done;
1324 driver = to_usb_driver(intf->dev.driver);
1325
1326 /* at this time we know the driver supports suspend */
1327 status = driver->suspend(intf, msg);
1328 if (status && !PMSG_IS_AUTO(msg))
1329 dev_err(&intf->dev, "suspend error %d\n", status);
1330
1331 done:
1332 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1333 return status;
1334}
1335
1336static int usb_resume_interface(struct usb_device *udev,
1337 struct usb_interface *intf, pm_message_t msg, int reset_resume)
1338{
1339 struct usb_driver *driver;
1340 int status = 0;
1341
1342 if (udev->state == USB_STATE_NOTATTACHED)
1343 goto done;
1344
1345 /* Don't let autoresume interfere with unbinding */
1346 if (intf->condition == USB_INTERFACE_UNBINDING)
1347 goto done;
1348
1349 /* Can't resume it if it doesn't have a driver. */
1350 if (intf->condition == USB_INTERFACE_UNBOUND) {
1351
1352 /* Carry out a deferred switch to altsetting 0 */
1353 if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1354 usb_set_interface(udev, intf->altsetting[0].
1355 desc.bInterfaceNumber, 0);
1356 intf->needs_altsetting0 = 0;
1357 }
1358 goto done;
1359 }
1360
1361 /* Don't resume if the interface is marked for rebinding */
1362 if (intf->needs_binding)
1363 goto done;
1364 driver = to_usb_driver(intf->dev.driver);
1365
1366 if (reset_resume) {
1367 if (driver->reset_resume) {
1368 status = driver->reset_resume(intf);
1369 if (status)
1370 dev_err(&intf->dev, "%s error %d\n",
1371 "reset_resume", status);
1372 } else {
1373 intf->needs_binding = 1;
1374 dev_dbg(&intf->dev, "no reset_resume for driver %s?\n",
1375 driver->name);
1376 }
1377 } else {
1378 status = driver->resume(intf);
1379 if (status)
1380 dev_err(&intf->dev, "resume error %d\n", status);
1381 }
1382
1383done:
1384 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1385
1386 /* Later we will unbind the driver and/or reprobe, if necessary */
1387 return status;
1388}
1389
1390/**
1391 * usb_suspend_both - suspend a USB device and its interfaces
1392 * @udev: the usb_device to suspend
1393 * @msg: Power Management message describing this state transition
1394 *
1395 * This is the central routine for suspending USB devices. It calls the
1396 * suspend methods for all the interface drivers in @udev and then calls
1397 * the suspend method for @udev itself. When the routine is called in
1398 * autosuspend, if an error occurs at any stage, all the interfaces
1399 * which were suspended are resumed so that they remain in the same
1400 * state as the device, but when called from system sleep, all error
1401 * from suspend methods of interfaces and the non-root-hub device itself
1402 * are simply ignored, so all suspended interfaces are only resumed
1403 * to the device's state when @udev is root-hub and its suspend method
1404 * returns failure.
1405 *
1406 * Autosuspend requests originating from a child device or an interface
1407 * driver may be made without the protection of @udev's device lock, but
1408 * all other suspend calls will hold the lock. Usbcore will insure that
1409 * method calls do not arrive during bind, unbind, or reset operations.
1410 * However drivers must be prepared to handle suspend calls arriving at
1411 * unpredictable times.
1412 *
1413 * This routine can run only in process context.
1414 *
1415 * Return: 0 if the suspend succeeded.
1416 */
1417static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1418{
1419 int status = 0;
1420 int i = 0, n = 0;
1421 struct usb_interface *intf;
1422 bool offload_active = false;
1423
1424 if (udev->state == USB_STATE_NOTATTACHED ||
1425 udev->state == USB_STATE_SUSPENDED)
1426 goto done;
1427
1428 usb_offload_set_pm_locked(udev, true);
1429 if (msg.event == PM_EVENT_SUSPEND && usb_offload_check(udev)) {
1430 dev_dbg(&udev->dev, "device offloaded, skip suspend.\n");
1431 offload_active = true;
1432 }
1433
1434 /* Suspend all the interfaces and then udev itself */
1435 if (udev->actconfig) {
1436 n = udev->actconfig->desc.bNumInterfaces;
1437 for (i = n - 1; i >= 0; --i) {
1438 intf = udev->actconfig->interface[i];
1439 /*
1440 * Don't suspend interfaces with remote wakeup while
1441 * the controller is active. This preserves pending
1442 * interrupt urbs, allowing interrupt events to be
1443 * handled during system suspend.
1444 */
1445 if (offload_active && intf->needs_remote_wakeup) {
1446 dev_dbg(&intf->dev,
1447 "device offloaded, skip suspend.\n");
1448 continue;
1449 }
1450 status = usb_suspend_interface(udev, intf, msg);
1451
1452 /* Ignore errors during system sleep transitions */
1453 if (!PMSG_IS_AUTO(msg))
1454 status = 0;
1455 if (status != 0)
1456 break;
1457 }
1458 }
1459 if (status == 0) {
1460 if (!offload_active)
1461 status = usb_suspend_device(udev, msg);
1462
1463 /*
1464 * Ignore errors from non-root-hub devices during
1465 * system sleep transitions. For the most part,
1466 * these devices should go to low power anyway when
1467 * the entire bus is suspended.
1468 */
1469 if (udev->parent && !PMSG_IS_AUTO(msg))
1470 status = 0;
1471
1472 /*
1473 * If the device is inaccessible, don't try to resume
1474 * suspended interfaces and just return the error.
1475 */
1476 if (status && status != -EBUSY) {
1477 int err;
1478 u16 devstat;
1479
1480 err = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
1481 &devstat);
1482 if (err) {
1483 dev_err(&udev->dev,
1484 "Failed to suspend device, error %d\n",
1485 status);
1486 goto done;
1487 }
1488 }
1489 }
1490
1491 /* If the suspend failed, resume interfaces that did get suspended */
1492 if (status != 0) {
1493 if (udev->actconfig) {
1494 msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1495 while (++i < n) {
1496 intf = udev->actconfig->interface[i];
1497 usb_resume_interface(udev, intf, msg, 0);
1498 }
1499 }
1500
1501 /* If the suspend succeeded then prevent any more URB submissions
1502 * and flush any outstanding URBs.
1503 */
1504 } else {
1505 udev->can_submit = 0;
1506 if (!offload_active) {
1507 for (i = 0; i < 16; ++i) {
1508 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1509 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1510 }
1511 }
1512 }
1513
1514 done:
1515 if (status != 0)
1516 usb_offload_set_pm_locked(udev, false);
1517 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1518 return status;
1519}
1520
1521/**
1522 * usb_resume_both - resume a USB device and its interfaces
1523 * @udev: the usb_device to resume
1524 * @msg: Power Management message describing this state transition
1525 *
1526 * This is the central routine for resuming USB devices. It calls the
1527 * resume method for @udev and then calls the resume methods for all
1528 * the interface drivers in @udev.
1529 *
1530 * Autoresume requests originating from a child device or an interface
1531 * driver may be made without the protection of @udev's device lock, but
1532 * all other resume calls will hold the lock. Usbcore will insure that
1533 * method calls do not arrive during bind, unbind, or reset operations.
1534 * However drivers must be prepared to handle resume calls arriving at
1535 * unpredictable times.
1536 *
1537 * This routine can run only in process context.
1538 *
1539 * Return: 0 on success.
1540 */
1541static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1542{
1543 int status = 0;
1544 int i;
1545 struct usb_interface *intf;
1546 bool offload_active = false;
1547
1548 if (udev->state == USB_STATE_NOTATTACHED) {
1549 status = -ENODEV;
1550 goto done;
1551 }
1552 udev->can_submit = 1;
1553 if (msg.event == PM_EVENT_RESUME)
1554 offload_active = usb_offload_check(udev);
1555
1556 /* Resume the device */
1557 if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) {
1558 if (!offload_active)
1559 status = usb_resume_device(udev, msg);
1560 else
1561 dev_dbg(&udev->dev,
1562 "device offloaded, skip resume.\n");
1563 }
1564
1565 /* Resume the interfaces */
1566 if (status == 0 && udev->actconfig) {
1567 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1568 intf = udev->actconfig->interface[i];
1569 /*
1570 * Interfaces with remote wakeup aren't suspended
1571 * while the controller is active. This preserves
1572 * pending interrupt urbs, allowing interrupt events
1573 * to be handled during system suspend.
1574 */
1575 if (offload_active && intf->needs_remote_wakeup) {
1576 dev_dbg(&intf->dev,
1577 "device offloaded, skip resume.\n");
1578 continue;
1579 }
1580 usb_resume_interface(udev, intf, msg,
1581 udev->reset_resume);
1582 }
1583 }
1584 usb_mark_last_busy(udev);
1585
1586 done:
1587 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1588 usb_offload_set_pm_locked(udev, false);
1589 if (!status)
1590 udev->reset_resume = 0;
1591 return status;
1592}
1593
1594static void choose_wakeup(struct usb_device *udev, pm_message_t msg)
1595{
1596 int w;
1597
1598 /*
1599 * For FREEZE/QUIESCE, disable remote wakeups so no interrupts get
1600 * generated.
1601 */
1602 if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
1603 w = 0;
1604
1605 } else {
1606 /*
1607 * Enable remote wakeup if it is allowed, even if no interface
1608 * drivers actually want it.
1609 */
1610 w = device_may_wakeup(&udev->dev);
1611 }
1612
1613 /*
1614 * If the device is autosuspended with the wrong wakeup setting,
1615 * autoresume now so the setting can be changed.
1616 */
1617 if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup)
1618 pm_runtime_resume(&udev->dev);
1619 udev->do_remote_wakeup = w;
1620}
1621
1622/* The device lock is held by the PM core */
1623int usb_suspend(struct device *dev, pm_message_t msg)
1624{
1625 struct usb_device *udev = to_usb_device(dev);
1626 int r;
1627
1628 unbind_no_pm_drivers_interfaces(udev);
1629
1630 /* From now on we are sure all drivers support suspend/resume
1631 * but not necessarily reset_resume()
1632 * so we may still need to unbind and rebind upon resume
1633 */
1634 choose_wakeup(udev, msg);
1635 r = usb_suspend_both(udev, msg);
1636 if (r)
1637 return r;
1638
1639 if (udev->quirks & USB_QUIRK_DISCONNECT_SUSPEND)
1640 usb_port_disable(udev);
1641
1642 return 0;
1643}
1644
1645/* The device lock is held by the PM core */
1646int usb_resume_complete(struct device *dev)
1647{
1648 struct usb_device *udev = to_usb_device(dev);
1649
1650 /* For PM complete calls, all we do is rebind interfaces
1651 * whose needs_binding flag is set
1652 */
1653 if (udev->state != USB_STATE_NOTATTACHED)
1654 rebind_marked_interfaces(udev);
1655 return 0;
1656}
1657
1658/* The device lock is held by the PM core */
1659int usb_resume(struct device *dev, pm_message_t msg)
1660{
1661 struct usb_device *udev = to_usb_device(dev);
1662 int status;
1663
1664 /* For all calls, take the device back to full power and
1665 * tell the PM core in case it was autosuspended previously.
1666 * Unbind the interfaces that will need rebinding later,
1667 * because they fail to support reset_resume.
1668 * (This can't be done in usb_resume_interface()
1669 * above because it doesn't own the right set of locks.)
1670 */
1671 status = usb_resume_both(udev, msg);
1672 if (status == 0) {
1673 pm_runtime_disable(dev);
1674 pm_runtime_set_active(dev);
1675 pm_runtime_enable(dev);
1676 unbind_marked_interfaces(udev);
1677 }
1678
1679 /* Avoid PM error messages for devices disconnected while suspended
1680 * as we'll display regular disconnect messages just a bit later.
1681 */
1682 if (status == -ENODEV || status == -ESHUTDOWN)
1683 status = 0;
1684 return status;
1685}
1686
1687/**
1688 * usb_enable_autosuspend - allow a USB device to be autosuspended
1689 * @udev: the USB device which may be autosuspended
1690 *
1691 * This routine allows @udev to be autosuspended. An autosuspend won't
1692 * take place until the autosuspend_delay has elapsed and all the other
1693 * necessary conditions are satisfied.
1694 *
1695 * The caller must hold @udev's device lock.
1696 */
1697void usb_enable_autosuspend(struct usb_device *udev)
1698{
1699 pm_runtime_allow(&udev->dev);
1700}
1701EXPORT_SYMBOL_GPL(usb_enable_autosuspend);
1702
1703/**
1704 * usb_disable_autosuspend - prevent a USB device from being autosuspended
1705 * @udev: the USB device which may not be autosuspended
1706 *
1707 * This routine prevents @udev from being autosuspended and wakes it up
1708 * if it is already autosuspended.
1709 *
1710 * The caller must hold @udev's device lock.
1711 */
1712void usb_disable_autosuspend(struct usb_device *udev)
1713{
1714 pm_runtime_forbid(&udev->dev);
1715}
1716EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
1717
1718/**
1719 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1720 * @udev: the usb_device to autosuspend
1721 *
1722 * This routine should be called when a core subsystem is finished using
1723 * @udev and wants to allow it to autosuspend. Examples would be when
1724 * @udev's device file in usbfs is closed or after a configuration change.
1725 *
1726 * @udev's usage counter is decremented; if it drops to 0 and all the
1727 * interfaces are inactive then a delayed autosuspend will be attempted.
1728 * The attempt may fail (see autosuspend_check()).
1729 *
1730 * The caller must hold @udev's device lock.
1731 *
1732 * This routine can run only in process context.
1733 */
1734void usb_autosuspend_device(struct usb_device *udev)
1735{
1736 int status;
1737
1738 usb_mark_last_busy(udev);
1739 status = pm_runtime_put_sync_autosuspend(&udev->dev);
1740 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1741 __func__, atomic_read(&udev->dev.power.usage_count),
1742 status);
1743}
1744
1745/**
1746 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1747 * @udev: the usb_device to autoresume
1748 *
1749 * This routine should be called when a core subsystem wants to use @udev
1750 * and needs to guarantee that it is not suspended. No autosuspend will
1751 * occur until usb_autosuspend_device() is called. (Note that this will
1752 * not prevent suspend events originating in the PM core.) Examples would
1753 * be when @udev's device file in usbfs is opened or when a remote-wakeup
1754 * request is received.
1755 *
1756 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1757 * However if the autoresume fails then the usage counter is re-decremented.
1758 *
1759 * The caller must hold @udev's device lock.
1760 *
1761 * This routine can run only in process context.
1762 *
1763 * Return: 0 on success. A negative error code otherwise.
1764 */
1765int usb_autoresume_device(struct usb_device *udev)
1766{
1767 int status;
1768
1769 status = pm_runtime_resume_and_get(&udev->dev);
1770 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1771 __func__, atomic_read(&udev->dev.power.usage_count),
1772 status);
1773 return status;
1774}
1775
1776/**
1777 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1778 * @intf: the usb_interface whose counter should be decremented
1779 *
1780 * This routine should be called by an interface driver when it is
1781 * finished using @intf and wants to allow it to autosuspend. A typical
1782 * example would be a character-device driver when its device file is
1783 * closed.
1784 *
1785 * The routine decrements @intf's usage counter. When the counter reaches
1786 * 0, a delayed autosuspend request for @intf's device is attempted. The
1787 * attempt may fail (see autosuspend_check()).
1788 *
1789 * This routine can run only in process context.
1790 */
1791void usb_autopm_put_interface(struct usb_interface *intf)
1792{
1793 struct usb_device *udev = interface_to_usbdev(intf);
1794 int status;
1795
1796 usb_mark_last_busy(udev);
1797 status = pm_runtime_put_sync(&intf->dev);
1798 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1799 __func__, atomic_read(&intf->dev.power.usage_count),
1800 status);
1801}
1802EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1803
1804/**
1805 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1806 * @intf: the usb_interface whose counter should be decremented
1807 *
1808 * This routine does much the same thing as usb_autopm_put_interface():
1809 * It decrements @intf's usage counter and schedules a delayed
1810 * autosuspend request if the counter is <= 0. The difference is that it
1811 * does not perform any synchronization; callers should hold a private
1812 * lock and handle all synchronization issues themselves.
1813 *
1814 * Typically a driver would call this routine during an URB's completion
1815 * handler, if no more URBs were pending.
1816 *
1817 * This routine can run in atomic context.
1818 */
1819void usb_autopm_put_interface_async(struct usb_interface *intf)
1820{
1821 struct usb_device *udev = interface_to_usbdev(intf);
1822
1823 usb_mark_last_busy(udev);
1824 pm_runtime_put(&intf->dev);
1825 dev_vdbg(&intf->dev, "%s: cnt %d\n",
1826 __func__, atomic_read(&intf->dev.power.usage_count));
1827}
1828EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1829
1830/**
1831 * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
1832 * @intf: the usb_interface whose counter should be decremented
1833 *
1834 * This routine decrements @intf's usage counter but does not carry out an
1835 * autosuspend.
1836 *
1837 * This routine can run in atomic context.
1838 */
1839void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
1840{
1841 struct usb_device *udev = interface_to_usbdev(intf);
1842
1843 usb_mark_last_busy(udev);
1844 pm_runtime_put_noidle(&intf->dev);
1845}
1846EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
1847
1848/**
1849 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1850 * @intf: the usb_interface whose counter should be incremented
1851 *
1852 * This routine should be called by an interface driver when it wants to
1853 * use @intf and needs to guarantee that it is not suspended. In addition,
1854 * the routine prevents @intf from being autosuspended subsequently. (Note
1855 * that this will not prevent suspend events originating in the PM core.)
1856 * This prevention will persist until usb_autopm_put_interface() is called
1857 * or @intf is unbound. A typical example would be a character-device
1858 * driver when its device file is opened.
1859 *
1860 * @intf's usage counter is incremented to prevent subsequent autosuspends.
1861 * However if the autoresume fails then the counter is re-decremented.
1862 *
1863 * This routine can run only in process context.
1864 *
1865 * Return: 0 on success.
1866 */
1867int usb_autopm_get_interface(struct usb_interface *intf)
1868{
1869 int status;
1870
1871 status = pm_runtime_resume_and_get(&intf->dev);
1872 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1873 __func__, atomic_read(&intf->dev.power.usage_count),
1874 status);
1875 return status;
1876}
1877EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1878
1879/**
1880 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1881 * @intf: the usb_interface whose counter should be incremented
1882 *
1883 * This routine does much the same thing as
1884 * usb_autopm_get_interface(): It increments @intf's usage counter and
1885 * queues an autoresume request if the device is suspended. The
1886 * differences are that it does not perform any synchronization (callers
1887 * should hold a private lock and handle all synchronization issues
1888 * themselves), and it does not autoresume the device directly (it only
1889 * queues a request). After a successful call, the device may not yet be
1890 * resumed.
1891 *
1892 * This routine can run in atomic context.
1893 *
1894 * Return: 0 on success. A negative error code otherwise.
1895 */
1896int usb_autopm_get_interface_async(struct usb_interface *intf)
1897{
1898 int status;
1899
1900 status = pm_runtime_get(&intf->dev);
1901 if (status < 0 && status != -EINPROGRESS)
1902 pm_runtime_put_noidle(&intf->dev);
1903 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1904 __func__, atomic_read(&intf->dev.power.usage_count),
1905 status);
1906 if (status > 0 || status == -EINPROGRESS)
1907 status = 0;
1908 return status;
1909}
1910EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1911
1912/**
1913 * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
1914 * @intf: the usb_interface whose counter should be incremented
1915 *
1916 * This routine increments @intf's usage counter but does not carry out an
1917 * autoresume.
1918 *
1919 * This routine can run in atomic context.
1920 */
1921void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
1922{
1923 struct usb_device *udev = interface_to_usbdev(intf);
1924
1925 usb_mark_last_busy(udev);
1926 pm_runtime_get_noresume(&intf->dev);
1927}
1928EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
1929
1930/* Internal routine to check whether we may autosuspend a device. */
1931static int autosuspend_check(struct usb_device *udev)
1932{
1933 int w, i;
1934 struct usb_interface *intf;
1935
1936 if (udev->state == USB_STATE_NOTATTACHED)
1937 return -ENODEV;
1938
1939 /* Fail if autosuspend is disabled, or any interfaces are in use, or
1940 * any interface drivers require remote wakeup but it isn't available.
1941 */
1942 w = 0;
1943 if (udev->actconfig) {
1944 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1945 intf = udev->actconfig->interface[i];
1946
1947 /* We don't need to check interfaces that are
1948 * disabled for runtime PM. Either they are unbound
1949 * or else their drivers don't support autosuspend
1950 * and so they are permanently active.
1951 */
1952 if (intf->dev.power.disable_depth)
1953 continue;
1954 if (atomic_read(&intf->dev.power.usage_count) > 0)
1955 return -EBUSY;
1956 w |= intf->needs_remote_wakeup;
1957
1958 /* Don't allow autosuspend if the device will need
1959 * a reset-resume and any of its interface drivers
1960 * doesn't include support or needs remote wakeup.
1961 */
1962 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1963 struct usb_driver *driver;
1964
1965 driver = to_usb_driver(intf->dev.driver);
1966 if (!driver->reset_resume ||
1967 intf->needs_remote_wakeup)
1968 return -EOPNOTSUPP;
1969 }
1970 }
1971 }
1972 if (w && !device_can_wakeup(&udev->dev)) {
1973 dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
1974 return -EOPNOTSUPP;
1975 }
1976
1977 /*
1978 * If the device is a direct child of the root hub and the HCD
1979 * doesn't handle wakeup requests, don't allow autosuspend when
1980 * wakeup is needed.
1981 */
1982 if (w && udev->parent == udev->bus->root_hub &&
1983 bus_to_hcd(udev->bus)->cant_recv_wakeups) {
1984 dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\n");
1985 return -EOPNOTSUPP;
1986 }
1987
1988 udev->do_remote_wakeup = w;
1989 return 0;
1990}
1991
1992int usb_runtime_suspend(struct device *dev)
1993{
1994 struct usb_device *udev = to_usb_device(dev);
1995 int status;
1996
1997 /* A USB device can be suspended if it passes the various autosuspend
1998 * checks. Runtime suspend for a USB device means suspending all the
1999 * interfaces and then the device itself.
2000 */
2001 if (autosuspend_check(udev) != 0)
2002 return -EAGAIN;
2003
2004 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
2005
2006 /* Allow a retry if autosuspend failed temporarily */
2007 if (status == -EAGAIN || status == -EBUSY)
2008 usb_mark_last_busy(udev);
2009
2010 /*
2011 * The PM core reacts badly unless the return code is 0,
2012 * -EAGAIN, or -EBUSY, so always return -EBUSY on an error
2013 * (except for root hubs, because they don't suspend through
2014 * an upstream port like other USB devices).
2015 */
2016 if (status != 0 && udev->parent)
2017 return -EBUSY;
2018 return status;
2019}
2020
2021int usb_runtime_resume(struct device *dev)
2022{
2023 struct usb_device *udev = to_usb_device(dev);
2024 int status;
2025
2026 /* Runtime resume for a USB device means resuming both the device
2027 * and all its interfaces.
2028 */
2029 status = usb_resume_both(udev, PMSG_AUTO_RESUME);
2030 return status;
2031}
2032
2033int usb_runtime_idle(struct device *dev)
2034{
2035 struct usb_device *udev = to_usb_device(dev);
2036
2037 /* An idle USB device can be suspended if it passes the various
2038 * autosuspend checks.
2039 */
2040 if (autosuspend_check(udev) == 0)
2041 pm_runtime_autosuspend(dev);
2042 /* Tell the core not to suspend it, though. */
2043 return -EBUSY;
2044}
2045
2046static int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
2047{
2048 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2049 int ret = -EPERM;
2050
2051 if (hcd->driver->set_usb2_hw_lpm) {
2052 ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable);
2053 if (!ret)
2054 udev->usb2_hw_lpm_enabled = enable;
2055 }
2056
2057 return ret;
2058}
2059
2060int usb_enable_usb2_hardware_lpm(struct usb_device *udev)
2061{
2062 if (!udev->usb2_hw_lpm_capable ||
2063 !udev->usb2_hw_lpm_allowed ||
2064 udev->usb2_hw_lpm_enabled)
2065 return 0;
2066
2067 return usb_set_usb2_hardware_lpm(udev, 1);
2068}
2069
2070int usb_disable_usb2_hardware_lpm(struct usb_device *udev)
2071{
2072 if (!udev->usb2_hw_lpm_enabled)
2073 return 0;
2074
2075 return usb_set_usb2_hardware_lpm(udev, 0);
2076}
2077
2078#endif /* CONFIG_PM */
2079
2080const struct bus_type usb_bus_type = {
2081 .name = "usb",
2082 .match = usb_device_match,
2083 .uevent = usb_uevent,
2084 .need_parent_lock = true,
2085};