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 */
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(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 mutex_lock(lock: &usb_dynids_lock);
99 list_add_tail(new: &dynid->node, head: &dynids->list);
100 mutex_unlock(lock: &usb_dynids_lock);
101
102 retval = driver_attach(drv: driver);
103
104 if (retval)
105 return retval;
106 return count;
107
108fail:
109 kfree(objp: 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)(T: &usb_dynids_lock);
120 list_for_each_entry(dynid, &dynids->list, node)
121 if (dynid->id.bInterfaceClass != 0)
122 count += sysfs_emit_at(buf, at: count, fmt: "%04x %04x %02x\n",
123 dynid->id.idVendor, dynid->id.idProduct,
124 dynid->id.bInterfaceClass);
125 else
126 count += sysfs_emit_at(buf, at: count, fmt: "%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)(T: &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(entry: &dynid->node);
171 kfree(objp: 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(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 }
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(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
219static void usb_free_dynids(struct usb_driver *usb_drv)
220{
221 struct usb_dynid *dynid, *n;
222
223 guard(mutex)(T: &usb_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}
229
230static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
231 const struct usb_driver *drv)
232{
233 struct usb_dynid *dynid;
234
235 guard(mutex)(T: &usb_dynids_lock);
236 list_for_each_entry(dynid, &drv->dynids.list, node) {
237 if (usb_match_one_id(interface: intf, id: &dynid->id)) {
238 return &dynid->id;
239 }
240 }
241 return NULL;
242}
243
244
245/* called from driver core with dev locked */
246static int usb_probe_device(struct device *dev)
247{
248 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
249 struct usb_device *udev = to_usb_device(dev);
250 int error = 0;
251
252 dev_dbg(dev, "%s\n", __func__);
253
254 /* TODO: Add real matching code */
255
256 /* The device should always appear to be in use
257 * unless the driver supports autosuspend.
258 */
259 if (!udriver->supports_autosuspend)
260 error = usb_autoresume_device(udev);
261 if (error)
262 return error;
263
264 if (udriver->generic_subclass)
265 error = usb_generic_driver_probe(udev);
266 if (error)
267 return error;
268
269 /* Probe the USB device with the driver in hand, but only
270 * defer to a generic driver in case the current USB
271 * device driver has an id_table or a match function; i.e.,
272 * when the device driver was explicitly matched against
273 * a device.
274 *
275 * If the device driver does not have either of these,
276 * then we assume that it can bind to any device and is
277 * not truly a more specialized/non-generic driver, so a
278 * return value of -ENODEV should not force the device
279 * to be handled by the generic USB driver, as there
280 * can still be another, more specialized, device driver.
281 *
282 * This accommodates the usbip driver.
283 *
284 * TODO: What if, in the future, there are multiple
285 * specialized USB device drivers for a particular device?
286 * In such cases, there is a need to try all matching
287 * specialised device drivers prior to setting the
288 * use_generic_driver bit.
289 */
290 if (udriver->probe)
291 error = udriver->probe(udev);
292 else if (!udriver->generic_subclass)
293 error = -EINVAL;
294 if (error == -ENODEV && udriver != &usb_generic_driver &&
295 (udriver->id_table || udriver->match)) {
296 udev->use_generic_driver = 1;
297 return -EPROBE_DEFER;
298 }
299 return error;
300}
301
302/* called from driver core with dev locked */
303static int usb_unbind_device(struct device *dev)
304{
305 struct usb_device *udev = to_usb_device(dev);
306 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
307
308 if (udriver->disconnect)
309 udriver->disconnect(udev);
310 if (udriver->generic_subclass)
311 usb_generic_driver_disconnect(udev);
312 if (!udriver->supports_autosuspend)
313 usb_autosuspend_device(udev);
314 return 0;
315}
316
317/* called from driver core with dev locked */
318static int usb_probe_interface(struct device *dev)
319{
320 struct usb_driver *driver = to_usb_driver(dev->driver);
321 struct usb_interface *intf = to_usb_interface(dev);
322 struct usb_device *udev = interface_to_usbdev(intf);
323 const struct usb_device_id *id;
324 int error = -ENODEV;
325 int lpm_disable_error = -ENODEV;
326
327 dev_dbg(dev, "%s\n", __func__);
328
329 intf->needs_binding = 0;
330
331 if (usb_device_is_owned(udev))
332 return error;
333
334 if (udev->authorized == 0) {
335 dev_info(&intf->dev, "Device is not authorized for usage\n");
336 return error;
337 } else if (intf->authorized == 0) {
338 dev_info(&intf->dev, "Interface %d is not authorized for usage\n",
339 intf->altsetting->desc.bInterfaceNumber);
340 return error;
341 }
342
343 id = usb_match_dynamic_id(intf, drv: driver);
344 if (!id)
345 id = usb_match_id(interface: intf, id: driver->id_table);
346 if (!id)
347 return error;
348
349 dev_dbg(dev, "%s - got id\n", __func__);
350
351 error = usb_autoresume_device(udev);
352 if (error)
353 return error;
354
355 intf->condition = USB_INTERFACE_BINDING;
356
357 /* Probed interfaces are initially active. They are
358 * runtime-PM-enabled only if the driver has autosuspend support.
359 * They are sensitive to their children's power states.
360 */
361 pm_runtime_set_active(dev);
362 pm_suspend_ignore_children(dev, enable: false);
363 if (driver->supports_autosuspend)
364 pm_runtime_enable(dev);
365
366 /* If the new driver doesn't allow hub-initiated LPM, and we can't
367 * disable hub-initiated LPM, then fail the probe.
368 *
369 * Otherwise, leaving LPM enabled should be harmless, because the
370 * endpoint intervals should remain the same, and the U1/U2 timeouts
371 * should remain the same.
372 *
373 * If we need to install alt setting 0 before probe, or another alt
374 * setting during probe, that should also be fine. usb_set_interface()
375 * will attempt to disable LPM, and fail if it can't disable it.
376 */
377 if (driver->disable_hub_initiated_lpm) {
378 lpm_disable_error = usb_unlocked_disable_lpm(udev);
379 if (lpm_disable_error) {
380 dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n",
381 __func__, driver->name);
382 error = lpm_disable_error;
383 goto err;
384 }
385 }
386
387 /* Carry out a deferred switch to altsetting 0 */
388 if (intf->needs_altsetting0) {
389 error = usb_set_interface(dev: udev, ifnum: intf->altsetting[0].
390 desc.bInterfaceNumber, alternate: 0);
391 if (error < 0)
392 goto err;
393 intf->needs_altsetting0 = 0;
394 }
395
396 error = driver->probe(intf, id);
397 if (error)
398 goto err;
399
400 intf->condition = USB_INTERFACE_BOUND;
401
402 /* If the LPM disable succeeded, balance the ref counts. */
403 if (!lpm_disable_error)
404 usb_unlocked_enable_lpm(udev);
405
406 usb_autosuspend_device(udev);
407 return error;
408
409 err:
410 usb_set_intfdata(intf, NULL);
411 intf->needs_remote_wakeup = 0;
412 intf->condition = USB_INTERFACE_UNBOUND;
413
414 /* If the LPM disable succeeded, balance the ref counts. */
415 if (!lpm_disable_error)
416 usb_unlocked_enable_lpm(udev);
417
418 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
419 if (driver->supports_autosuspend)
420 pm_runtime_disable(dev);
421 pm_runtime_set_suspended(dev);
422
423 usb_autosuspend_device(udev);
424 return error;
425}
426
427/* called from driver core with dev locked */
428static int usb_unbind_interface(struct device *dev)
429{
430 struct usb_driver *driver = to_usb_driver(dev->driver);
431 struct usb_interface *intf = to_usb_interface(dev);
432 struct usb_host_endpoint *ep, **eps = NULL;
433 struct usb_device *udev;
434 int i, j, error, r;
435 int lpm_disable_error = -ENODEV;
436
437 intf->condition = USB_INTERFACE_UNBINDING;
438
439 /* Autoresume for set_interface call below */
440 udev = interface_to_usbdev(intf);
441 error = usb_autoresume_device(udev);
442
443 /* If hub-initiated LPM policy may change, attempt to disable LPM until
444 * the driver is unbound. If LPM isn't disabled, that's fine because it
445 * wouldn't be enabled unless all the bound interfaces supported
446 * hub-initiated LPM.
447 */
448 if (driver->disable_hub_initiated_lpm)
449 lpm_disable_error = usb_unlocked_disable_lpm(udev);
450
451 /*
452 * Terminate all URBs for this interface unless the driver
453 * supports "soft" unbinding and the device is still present.
454 */
455 if (!driver->soft_unbind || udev->state == USB_STATE_NOTATTACHED)
456 usb_disable_interface(dev: udev, intf, reset_hardware: false);
457
458 driver->disconnect(intf);
459
460 /* Free streams */
461 for (i = 0, j = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
462 ep = &intf->cur_altsetting->endpoint[i];
463 if (ep->streams == 0)
464 continue;
465 if (j == 0) {
466 eps = kmalloc_array(USB_MAXENDPOINTS, sizeof(void *),
467 GFP_KERNEL);
468 if (!eps)
469 break;
470 }
471 eps[j++] = ep;
472 }
473 if (j) {
474 usb_free_streams(interface: intf, eps, num_eps: j, GFP_KERNEL);
475 kfree(objp: eps);
476 }
477
478 /* Reset other interface state.
479 * We cannot do a Set-Interface if the device is suspended or
480 * if it is prepared for a system sleep (since installing a new
481 * altsetting means creating new endpoint device entries).
482 * When either of these happens, defer the Set-Interface.
483 */
484 if (intf->cur_altsetting->desc.bAlternateSetting == 0) {
485 /* Already in altsetting 0 so skip Set-Interface.
486 * Just re-enable it without affecting the endpoint toggles.
487 */
488 usb_enable_interface(dev: udev, intf, reset_toggles: false);
489 } else if (!error && !intf->dev.power.is_prepared) {
490 r = usb_set_interface(dev: udev, ifnum: intf->altsetting[0].
491 desc.bInterfaceNumber, alternate: 0);
492 if (r < 0)
493 intf->needs_altsetting0 = 1;
494 } else {
495 intf->needs_altsetting0 = 1;
496 }
497 usb_set_intfdata(intf, NULL);
498
499 intf->condition = USB_INTERFACE_UNBOUND;
500 intf->needs_remote_wakeup = 0;
501
502 /* Attempt to re-enable USB3 LPM, if the disable succeeded. */
503 if (!lpm_disable_error)
504 usb_unlocked_enable_lpm(udev);
505
506 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
507 if (driver->supports_autosuspend)
508 pm_runtime_disable(dev);
509 pm_runtime_set_suspended(dev);
510
511 if (!error)
512 usb_autosuspend_device(udev);
513
514 return 0;
515}
516
517static void usb_shutdown_interface(struct device *dev)
518{
519 struct usb_interface *intf = to_usb_interface(dev);
520 struct usb_driver *driver;
521
522 if (!dev->driver)
523 return;
524
525 driver = to_usb_driver(dev->driver);
526 if (driver->shutdown)
527 driver->shutdown(intf);
528}
529
530/**
531 * usb_driver_claim_interface - bind a driver to an interface
532 * @driver: the driver to be bound
533 * @iface: the interface to which it will be bound; must be in the
534 * usb device's active configuration
535 * @data: driver data associated with that interface
536 *
537 * This is used by usb device drivers that need to claim more than one
538 * interface on a device when probing (audio and acm are current examples).
539 * No device driver should directly modify internal usb_interface or
540 * usb_device structure members.
541 *
542 * Callers must own the device lock, so driver probe() entries don't need
543 * extra locking, but other call contexts may need to explicitly claim that
544 * lock.
545 *
546 * Return: 0 on success.
547 */
548int usb_driver_claim_interface(struct usb_driver *driver,
549 struct usb_interface *iface, void *data)
550{
551 struct device *dev;
552 int retval = 0;
553
554 if (!iface)
555 return -ENODEV;
556
557 dev = &iface->dev;
558 if (dev->driver)
559 return -EBUSY;
560
561 /* reject claim if interface is not authorized */
562 if (!iface->authorized)
563 return -ENODEV;
564
565 dev->driver = &driver->driver;
566 usb_set_intfdata(intf: iface, data);
567 iface->needs_binding = 0;
568
569 iface->condition = USB_INTERFACE_BOUND;
570
571 /* Claimed interfaces are initially inactive (suspended) and
572 * runtime-PM-enabled, but only if the driver has autosuspend
573 * support. Otherwise they are marked active, to prevent the
574 * device from being autosuspended, but left disabled. In either
575 * case they are sensitive to their children's power states.
576 */
577 pm_suspend_ignore_children(dev, enable: false);
578 if (driver->supports_autosuspend)
579 pm_runtime_enable(dev);
580 else
581 pm_runtime_set_active(dev);
582
583 /* if interface was already added, bind now; else let
584 * the future device_add() bind it, bypassing probe()
585 */
586 if (device_is_registered(dev))
587 retval = device_bind_driver(dev);
588
589 if (retval) {
590 dev->driver = NULL;
591 usb_set_intfdata(intf: iface, NULL);
592 iface->needs_remote_wakeup = 0;
593 iface->condition = USB_INTERFACE_UNBOUND;
594
595 /*
596 * Unbound interfaces are always runtime-PM-disabled
597 * and runtime-PM-suspended
598 */
599 if (driver->supports_autosuspend)
600 pm_runtime_disable(dev);
601 pm_runtime_set_suspended(dev);
602 }
603
604 return retval;
605}
606EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
607
608/**
609 * usb_driver_release_interface - unbind a driver from an interface
610 * @driver: the driver to be unbound
611 * @iface: the interface from which it will be unbound
612 *
613 * This can be used by drivers to release an interface without waiting
614 * for their disconnect() methods to be called. In typical cases this
615 * also causes the driver disconnect() method to be called.
616 *
617 * This call is synchronous, and may not be used in an interrupt context.
618 * Callers must own the device lock, so driver disconnect() entries don't
619 * need extra locking, but other call contexts may need to explicitly claim
620 * that lock.
621 */
622void usb_driver_release_interface(struct usb_driver *driver,
623 struct usb_interface *iface)
624{
625 struct device *dev = &iface->dev;
626
627 /* this should never happen, don't release something that's not ours */
628 if (!dev->driver || dev->driver != &driver->driver)
629 return;
630
631 /* don't release from within disconnect() */
632 if (iface->condition != USB_INTERFACE_BOUND)
633 return;
634 iface->condition = USB_INTERFACE_UNBINDING;
635
636 /* Release via the driver core only if the interface
637 * has already been registered
638 */
639 if (device_is_registered(dev)) {
640 device_release_driver(dev);
641 } else {
642 device_lock(dev);
643 usb_unbind_interface(dev);
644 dev->driver = NULL;
645 device_unlock(dev);
646 }
647}
648EXPORT_SYMBOL_GPL(usb_driver_release_interface);
649
650/* returns 0 if no match, 1 if match */
651int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
652{
653 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
654 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
655 return 0;
656
657 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
658 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
659 return 0;
660
661 /* No need to test id->bcdDevice_lo != 0, since 0 is never
662 greater than any unsigned number. */
663 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
664 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
665 return 0;
666
667 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
668 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
669 return 0;
670
671 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
672 (id->bDeviceClass != dev->descriptor.bDeviceClass))
673 return 0;
674
675 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
676 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
677 return 0;
678
679 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
680 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
681 return 0;
682
683 return 1;
684}
685
686/* returns 0 if no match, 1 if match */
687int usb_match_one_id_intf(struct usb_device *dev,
688 struct usb_host_interface *intf,
689 const struct usb_device_id *id)
690{
691 /* The interface class, subclass, protocol and number should never be
692 * checked for a match if the device class is Vendor Specific,
693 * unless the match record specifies the Vendor ID. */
694 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
695 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
696 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
697 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
698 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
699 USB_DEVICE_ID_MATCH_INT_NUMBER)))
700 return 0;
701
702 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
703 (id->bInterfaceClass != intf->desc.bInterfaceClass))
704 return 0;
705
706 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
707 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
708 return 0;
709
710 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
711 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
712 return 0;
713
714 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
715 (id->bInterfaceNumber != intf->desc.bInterfaceNumber))
716 return 0;
717
718 return 1;
719}
720
721/* returns 0 if no match, 1 if match */
722int usb_match_one_id(struct usb_interface *interface,
723 const struct usb_device_id *id)
724{
725 struct usb_host_interface *intf;
726 struct usb_device *dev;
727
728 /* proc_connectinfo in devio.c may call us with id == NULL. */
729 if (id == NULL)
730 return 0;
731
732 intf = interface->cur_altsetting;
733 dev = interface_to_usbdev(interface);
734
735 if (!usb_match_device(dev, id))
736 return 0;
737
738 return usb_match_one_id_intf(dev, intf, id);
739}
740EXPORT_SYMBOL_GPL(usb_match_one_id);
741
742/**
743 * usb_match_id - find first usb_device_id matching device or interface
744 * @interface: the interface of interest
745 * @id: array of usb_device_id structures, terminated by zero entry
746 *
747 * usb_match_id searches an array of usb_device_id's and returns
748 * the first one matching the device or interface, or null.
749 * This is used when binding (or rebinding) a driver to an interface.
750 * Most USB device drivers will use this indirectly, through the usb core,
751 * but some layered driver frameworks use it directly.
752 * These device tables are exported with MODULE_DEVICE_TABLE, through
753 * modutils, to support the driver loading functionality of USB hotplugging.
754 *
755 * Return: The first matching usb_device_id, or %NULL.
756 *
757 * What Matches:
758 *
759 * The "match_flags" element in a usb_device_id controls which
760 * members are used. If the corresponding bit is set, the
761 * value in the device_id must match its corresponding member
762 * in the device or interface descriptor, or else the device_id
763 * does not match.
764 *
765 * "driver_info" is normally used only by device drivers,
766 * but you can create a wildcard "matches anything" usb_device_id
767 * as a driver's "modules.usbmap" entry if you provide an id with
768 * only a nonzero "driver_info" field. If you do this, the USB device
769 * driver's probe() routine should use additional intelligence to
770 * decide whether to bind to the specified interface.
771 *
772 * What Makes Good usb_device_id Tables:
773 *
774 * The match algorithm is very simple, so that intelligence in
775 * driver selection must come from smart driver id records.
776 * Unless you have good reasons to use another selection policy,
777 * provide match elements only in related groups, and order match
778 * specifiers from specific to general. Use the macros provided
779 * for that purpose if you can.
780 *
781 * The most specific match specifiers use device descriptor
782 * data. These are commonly used with product-specific matches;
783 * the USB_DEVICE macro lets you provide vendor and product IDs,
784 * and you can also match against ranges of product revisions.
785 * These are widely used for devices with application or vendor
786 * specific bDeviceClass values.
787 *
788 * Matches based on device class/subclass/protocol specifications
789 * are slightly more general; use the USB_DEVICE_INFO macro, or
790 * its siblings. These are used with single-function devices
791 * where bDeviceClass doesn't specify that each interface has
792 * its own class.
793 *
794 * Matches based on interface class/subclass/protocol are the
795 * most general; they let drivers bind to any interface on a
796 * multiple-function device. Use the USB_INTERFACE_INFO
797 * macro, or its siblings, to match class-per-interface style
798 * devices (as recorded in bInterfaceClass).
799 *
800 * Note that an entry created by USB_INTERFACE_INFO won't match
801 * any interface if the device class is set to Vendor-Specific.
802 * This is deliberate; according to the USB spec the meanings of
803 * the interface class/subclass/protocol for these devices are also
804 * vendor-specific, and hence matching against a standard product
805 * class wouldn't work anyway. If you really want to use an
806 * interface-based match for such a device, create a match record
807 * that also specifies the vendor ID. (Unforunately there isn't a
808 * standard macro for creating records like this.)
809 *
810 * Within those groups, remember that not all combinations are
811 * meaningful. For example, don't give a product version range
812 * without vendor and product IDs; or specify a protocol without
813 * its associated class and subclass.
814 */
815const struct usb_device_id *usb_match_id(struct usb_interface *interface,
816 const struct usb_device_id *id)
817{
818 /* proc_connectinfo in devio.c may call us with id == NULL. */
819 if (id == NULL)
820 return NULL;
821
822 /* It is important to check that id->driver_info is nonzero,
823 since an entry that is all zeroes except for a nonzero
824 id->driver_info is the way to create an entry that
825 indicates that the driver want to examine every
826 device and interface. */
827 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
828 id->bInterfaceClass || id->driver_info; id++) {
829 if (usb_match_one_id(interface, id))
830 return id;
831 }
832
833 return NULL;
834}
835EXPORT_SYMBOL_GPL(usb_match_id);
836
837const struct usb_device_id *usb_device_match_id(struct usb_device *udev,
838 const struct usb_device_id *id)
839{
840 if (!id)
841 return NULL;
842
843 for (; id->idVendor || id->idProduct ; id++) {
844 if (usb_match_device(dev: udev, id))
845 return id;
846 }
847
848 return NULL;
849}
850EXPORT_SYMBOL_GPL(usb_device_match_id);
851
852bool usb_driver_applicable(struct usb_device *udev,
853 const struct usb_device_driver *udrv)
854{
855 if (udrv->id_table && udrv->match)
856 return usb_device_match_id(udev, udrv->id_table) != NULL &&
857 udrv->match(udev);
858
859 if (udrv->id_table)
860 return usb_device_match_id(udev, udrv->id_table) != NULL;
861
862 if (udrv->match)
863 return udrv->match(udev);
864
865 return false;
866}
867
868static int usb_device_match(struct device *dev, const struct device_driver *drv)
869{
870 /* devices and interfaces are handled separately */
871 if (is_usb_device(dev)) {
872 struct usb_device *udev;
873 const struct usb_device_driver *udrv;
874
875 /* interface drivers never match devices */
876 if (!is_usb_device_driver(drv))
877 return 0;
878
879 udev = to_usb_device(dev);
880 udrv = to_usb_device_driver(drv);
881
882 /* If the device driver under consideration does not have a
883 * id_table or a match function, then let the driver's probe
884 * function decide.
885 */
886 if (!udrv->id_table && !udrv->match)
887 return 1;
888
889 return usb_driver_applicable(udev, udrv);
890
891 } else if (is_usb_interface(dev)) {
892 struct usb_interface *intf;
893 const struct usb_driver *usb_drv;
894 const struct usb_device_id *id;
895
896 /* device drivers never match interfaces */
897 if (is_usb_device_driver(drv))
898 return 0;
899
900 intf = to_usb_interface(dev);
901 usb_drv = to_usb_driver(drv);
902
903 id = usb_match_id(intf, usb_drv->id_table);
904 if (id)
905 return 1;
906
907 id = usb_match_dynamic_id(intf, drv: usb_drv);
908 if (id)
909 return 1;
910 }
911
912 return 0;
913}
914
915static int usb_uevent(const struct device *dev, struct kobj_uevent_env *env)
916{
917 const struct usb_device *usb_dev;
918
919 if (is_usb_device(dev)) {
920 usb_dev = to_usb_device(dev);
921 } else if (is_usb_interface(dev)) {
922 const struct usb_interface *intf = to_usb_interface(dev);
923
924 usb_dev = interface_to_usbdev(intf);
925 } else {
926 return 0;
927 }
928
929 if (usb_dev->devnum < 0) {
930 /* driver is often null here; dev_dbg() would oops */
931 pr_debug("usb %s: already deleted?\n", dev_name(dev));
932 return -ENODEV;
933 }
934 if (!usb_dev->bus) {
935 pr_debug("usb %s: bus removed?\n", dev_name(dev));
936 return -ENODEV;
937 }
938
939 /* per-device configurations are common */
940 if (add_uevent_var(env, format: "PRODUCT=%x/%x/%x",
941 le16_to_cpu(usb_dev->descriptor.idVendor),
942 le16_to_cpu(usb_dev->descriptor.idProduct),
943 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
944 return -ENOMEM;
945
946 /* class-based driver binding models */
947 if (add_uevent_var(env, format: "TYPE=%d/%d/%d",
948 usb_dev->descriptor.bDeviceClass,
949 usb_dev->descriptor.bDeviceSubClass,
950 usb_dev->descriptor.bDeviceProtocol))
951 return -ENOMEM;
952
953 return 0;
954}
955
956static int __usb_bus_reprobe_drivers(struct device *dev, void *data)
957{
958 struct usb_device_driver *new_udriver = data;
959 struct usb_device *udev;
960 int ret;
961
962 /* Don't reprobe if current driver isn't usb_generic_driver */
963 if (dev->driver != &usb_generic_driver.driver)
964 return 0;
965
966 udev = to_usb_device(dev);
967 if (!usb_driver_applicable(udev, udrv: new_udriver))
968 return 0;
969
970 ret = device_reprobe(dev);
971 if (ret && ret != -EPROBE_DEFER)
972 dev_err(dev, "Failed to reprobe device (error %d)\n", ret);
973
974 return 0;
975}
976
977bool is_usb_device_driver(const struct device_driver *drv)
978{
979 return drv->probe == usb_probe_device;
980}
981
982/**
983 * usb_register_device_driver - register a USB device (not interface) driver
984 * @new_udriver: USB operations for the device driver
985 * @owner: module owner of this driver.
986 *
987 * Registers a USB device driver with the USB core. The list of
988 * unattached devices will be rescanned whenever a new driver is
989 * added, allowing the new driver to attach to any recognized devices.
990 *
991 * Return: A negative error code on failure and 0 on success.
992 */
993int usb_register_device_driver(struct usb_device_driver *new_udriver,
994 struct module *owner)
995{
996 int retval = 0;
997
998 if (usb_disabled())
999 return -ENODEV;
1000
1001 new_udriver->driver.name = new_udriver->name;
1002 new_udriver->driver.bus = &usb_bus_type;
1003 new_udriver->driver.probe = usb_probe_device;
1004 new_udriver->driver.remove = usb_unbind_device;
1005 new_udriver->driver.owner = owner;
1006 new_udriver->driver.dev_groups = new_udriver->dev_groups;
1007
1008 retval = driver_register(drv: &new_udriver->driver);
1009
1010 if (!retval) {
1011 pr_info("%s: registered new device driver %s\n",
1012 usbcore_name, new_udriver->name);
1013 /*
1014 * Check whether any device could be better served with
1015 * this new driver
1016 */
1017 bus_for_each_dev(bus: &usb_bus_type, NULL, data: new_udriver,
1018 fn: __usb_bus_reprobe_drivers);
1019 } else {
1020 pr_err("%s: error %d registering device driver %s\n",
1021 usbcore_name, retval, new_udriver->name);
1022 }
1023
1024 return retval;
1025}
1026EXPORT_SYMBOL_GPL(usb_register_device_driver);
1027
1028/**
1029 * usb_deregister_device_driver - unregister a USB device (not interface) driver
1030 * @udriver: USB operations of the device driver to unregister
1031 * Context: must be able to sleep
1032 *
1033 * Unlinks the specified driver from the internal USB driver list.
1034 */
1035void usb_deregister_device_driver(struct usb_device_driver *udriver)
1036{
1037 pr_info("%s: deregistering device driver %s\n",
1038 usbcore_name, udriver->name);
1039
1040 driver_unregister(drv: &udriver->driver);
1041}
1042EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
1043
1044/**
1045 * usb_register_driver - register a USB interface driver
1046 * @new_driver: USB operations for the interface driver
1047 * @owner: module owner of this driver.
1048 * @mod_name: module name string
1049 *
1050 * Registers a USB interface driver with the USB core. The list of
1051 * unattached interfaces will be rescanned whenever a new driver is
1052 * added, allowing the new driver to attach to any recognized interfaces.
1053 *
1054 * Return: A negative error code on failure and 0 on success.
1055 *
1056 * NOTE: if you want your driver to use the USB major number, you must call
1057 * usb_register_dev() to enable that functionality. This function no longer
1058 * takes care of that.
1059 */
1060int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
1061 const char *mod_name)
1062{
1063 int retval = 0;
1064
1065 if (usb_disabled())
1066 return -ENODEV;
1067
1068 new_driver->driver.name = new_driver->name;
1069 new_driver->driver.bus = &usb_bus_type;
1070 new_driver->driver.probe = usb_probe_interface;
1071 new_driver->driver.remove = usb_unbind_interface;
1072 new_driver->driver.shutdown = usb_shutdown_interface;
1073 new_driver->driver.owner = owner;
1074 new_driver->driver.mod_name = mod_name;
1075 new_driver->driver.dev_groups = new_driver->dev_groups;
1076 INIT_LIST_HEAD(list: &new_driver->dynids.list);
1077
1078 retval = driver_register(drv: &new_driver->driver);
1079 if (retval)
1080 goto out;
1081
1082 retval = usb_create_newid_files(usb_drv: new_driver);
1083 if (retval)
1084 goto out_newid;
1085
1086 pr_info("%s: registered new interface driver %s\n",
1087 usbcore_name, new_driver->name);
1088
1089 return 0;
1090
1091out_newid:
1092 driver_unregister(drv: &new_driver->driver);
1093out:
1094 pr_err("%s: error %d registering interface driver %s\n",
1095 usbcore_name, retval, new_driver->name);
1096 return retval;
1097}
1098EXPORT_SYMBOL_GPL(usb_register_driver);
1099
1100/**
1101 * usb_deregister - unregister a USB interface driver
1102 * @driver: USB operations of the interface driver to unregister
1103 * Context: must be able to sleep
1104 *
1105 * Unlinks the specified driver from the internal USB driver list.
1106 *
1107 * NOTE: If you called usb_register_dev(), you still need to call
1108 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
1109 * this * call will no longer do it for you.
1110 */
1111void usb_deregister(struct usb_driver *driver)
1112{
1113 pr_info("%s: deregistering interface driver %s\n",
1114 usbcore_name, driver->name);
1115
1116 usb_remove_newid_files(usb_drv: driver);
1117 driver_unregister(drv: &driver->driver);
1118 usb_free_dynids(usb_drv: driver);
1119}
1120EXPORT_SYMBOL_GPL(usb_deregister);
1121
1122/* Forced unbinding of a USB interface driver, either because
1123 * it doesn't support pre_reset/post_reset/reset_resume or
1124 * because it doesn't support suspend/resume.
1125 *
1126 * The caller must hold @intf's device's lock, but not @intf's lock.
1127 */
1128void usb_forced_unbind_intf(struct usb_interface *intf)
1129{
1130 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
1131
1132 dev_dbg(&intf->dev, "forced unbind\n");
1133 usb_driver_release_interface(driver, intf);
1134
1135 /* Mark the interface for later rebinding */
1136 intf->needs_binding = 1;
1137}
1138
1139/*
1140 * Unbind drivers for @udev's marked interfaces. These interfaces have
1141 * the needs_binding flag set, for example by usb_resume_interface().
1142 *
1143 * The caller must hold @udev's device lock.
1144 */
1145static void unbind_marked_interfaces(struct usb_device *udev)
1146{
1147 struct usb_host_config *config;
1148 int i;
1149 struct usb_interface *intf;
1150
1151 config = udev->actconfig;
1152 if (config) {
1153 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1154 intf = config->interface[i];
1155 if (intf->dev.driver && intf->needs_binding)
1156 usb_forced_unbind_intf(intf);
1157 }
1158 }
1159}
1160
1161/* Delayed forced unbinding of a USB interface driver and scan
1162 * for rebinding.
1163 *
1164 * The caller must hold @intf's device's lock, but not @intf's lock.
1165 *
1166 * Note: Rebinds will be skipped if a system sleep transition is in
1167 * progress and the PM "complete" callback hasn't occurred yet.
1168 */
1169static void usb_rebind_intf(struct usb_interface *intf)
1170{
1171 int rc;
1172
1173 /* Delayed unbind of an existing driver */
1174 if (intf->dev.driver)
1175 usb_forced_unbind_intf(intf);
1176
1177 /* Try to rebind the interface */
1178 if (!intf->dev.power.is_prepared) {
1179 intf->needs_binding = 0;
1180 rc = device_attach(dev: &intf->dev);
1181 if (rc < 0 && rc != -EPROBE_DEFER)
1182 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
1183 }
1184}
1185
1186/*
1187 * Rebind drivers to @udev's marked interfaces. These interfaces have
1188 * the needs_binding flag set.
1189 *
1190 * The caller must hold @udev's device lock.
1191 */
1192static void rebind_marked_interfaces(struct usb_device *udev)
1193{
1194 struct usb_host_config *config;
1195 int i;
1196 struct usb_interface *intf;
1197
1198 config = udev->actconfig;
1199 if (config) {
1200 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1201 intf = config->interface[i];
1202 if (intf->needs_binding)
1203 usb_rebind_intf(intf);
1204 }
1205 }
1206}
1207
1208/*
1209 * Unbind all of @udev's marked interfaces and then rebind all of them.
1210 * This ordering is necessary because some drivers claim several interfaces
1211 * when they are first probed.
1212 *
1213 * The caller must hold @udev's device lock.
1214 */
1215void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev)
1216{
1217 unbind_marked_interfaces(udev);
1218 rebind_marked_interfaces(udev);
1219}
1220
1221#ifdef CONFIG_PM
1222
1223/* Unbind drivers for @udev's interfaces that don't support suspend/resume
1224 * There is no check for reset_resume here because it can be determined
1225 * only during resume whether reset_resume is needed.
1226 *
1227 * The caller must hold @udev's device lock.
1228 */
1229static void unbind_no_pm_drivers_interfaces(struct usb_device *udev)
1230{
1231 struct usb_host_config *config;
1232 int i;
1233 struct usb_interface *intf;
1234 struct usb_driver *drv;
1235
1236 config = udev->actconfig;
1237 if (config) {
1238 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1239 intf = config->interface[i];
1240
1241 if (intf->dev.driver) {
1242 drv = to_usb_driver(intf->dev.driver);
1243 if (!drv->suspend || !drv->resume)
1244 usb_forced_unbind_intf(intf);
1245 }
1246 }
1247 }
1248}
1249
1250static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
1251{
1252 struct usb_device_driver *udriver;
1253 int status = 0;
1254
1255 if (udev->state == USB_STATE_NOTATTACHED ||
1256 udev->state == USB_STATE_SUSPENDED)
1257 goto done;
1258
1259 /* For devices that don't have a driver, we do a generic suspend. */
1260 if (udev->dev.driver)
1261 udriver = to_usb_device_driver(udev->dev.driver);
1262 else {
1263 udev->do_remote_wakeup = 0;
1264 udriver = &usb_generic_driver;
1265 }
1266 if (udriver->suspend)
1267 status = udriver->suspend(udev, msg);
1268 if (status == 0 && udriver->generic_subclass)
1269 status = usb_generic_driver_suspend(udev, msg);
1270
1271 done:
1272 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1273 return status;
1274}
1275
1276static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1277{
1278 struct usb_device_driver *udriver;
1279 int status = 0;
1280
1281 if (udev->state == USB_STATE_NOTATTACHED)
1282 goto done;
1283
1284 /* Can't resume it if it doesn't have a driver. */
1285 if (udev->dev.driver == NULL) {
1286 status = -ENOTCONN;
1287 goto done;
1288 }
1289
1290 /* Non-root devices on a full/low-speed bus must wait for their
1291 * companion high-speed root hub, in case a handoff is needed.
1292 */
1293 if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion)
1294 device_pm_wait_for_dev(sub: &udev->dev,
1295 dev: &udev->bus->hs_companion->root_hub->dev);
1296
1297 if (udev->quirks & USB_QUIRK_RESET_RESUME)
1298 udev->reset_resume = 1;
1299
1300 udriver = to_usb_device_driver(udev->dev.driver);
1301 if (udriver->generic_subclass)
1302 status = usb_generic_driver_resume(udev, msg);
1303 if (status == 0 && udriver->resume)
1304 status = udriver->resume(udev, msg);
1305
1306 done:
1307 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1308 return status;
1309}
1310
1311static int usb_suspend_interface(struct usb_device *udev,
1312 struct usb_interface *intf, pm_message_t msg)
1313{
1314 struct usb_driver *driver;
1315 int status = 0;
1316
1317 if (udev->state == USB_STATE_NOTATTACHED ||
1318 intf->condition == USB_INTERFACE_UNBOUND)
1319 goto done;
1320 driver = to_usb_driver(intf->dev.driver);
1321
1322 /* at this time we know the driver supports suspend */
1323 status = driver->suspend(intf, msg);
1324 if (status && !PMSG_IS_AUTO(msg))
1325 dev_err(&intf->dev, "suspend error %d\n", status);
1326
1327 done:
1328 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1329 return status;
1330}
1331
1332static int usb_resume_interface(struct usb_device *udev,
1333 struct usb_interface *intf, pm_message_t msg, int reset_resume)
1334{
1335 struct usb_driver *driver;
1336 int status = 0;
1337
1338 if (udev->state == USB_STATE_NOTATTACHED)
1339 goto done;
1340
1341 /* Don't let autoresume interfere with unbinding */
1342 if (intf->condition == USB_INTERFACE_UNBINDING)
1343 goto done;
1344
1345 /* Can't resume it if it doesn't have a driver. */
1346 if (intf->condition == USB_INTERFACE_UNBOUND) {
1347
1348 /* Carry out a deferred switch to altsetting 0 */
1349 if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1350 usb_set_interface(dev: udev, ifnum: intf->altsetting[0].
1351 desc.bInterfaceNumber, alternate: 0);
1352 intf->needs_altsetting0 = 0;
1353 }
1354 goto done;
1355 }
1356
1357 /* Don't resume if the interface is marked for rebinding */
1358 if (intf->needs_binding)
1359 goto done;
1360 driver = to_usb_driver(intf->dev.driver);
1361
1362 if (reset_resume) {
1363 if (driver->reset_resume) {
1364 status = driver->reset_resume(intf);
1365 if (status)
1366 dev_err(&intf->dev, "%s error %d\n",
1367 "reset_resume", status);
1368 } else {
1369 intf->needs_binding = 1;
1370 dev_dbg(&intf->dev, "no reset_resume for driver %s?\n",
1371 driver->name);
1372 }
1373 } else {
1374 status = driver->resume(intf);
1375 if (status)
1376 dev_err(&intf->dev, "resume error %d\n", status);
1377 }
1378
1379done:
1380 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1381
1382 /* Later we will unbind the driver and/or reprobe, if necessary */
1383 return status;
1384}
1385
1386/**
1387 * usb_suspend_both - suspend a USB device and its interfaces
1388 * @udev: the usb_device to suspend
1389 * @msg: Power Management message describing this state transition
1390 *
1391 * This is the central routine for suspending USB devices. It calls the
1392 * suspend methods for all the interface drivers in @udev and then calls
1393 * the suspend method for @udev itself. When the routine is called in
1394 * autosuspend, if an error occurs at any stage, all the interfaces
1395 * which were suspended are resumed so that they remain in the same
1396 * state as the device, but when called from system sleep, all error
1397 * from suspend methods of interfaces and the non-root-hub device itself
1398 * are simply ignored, so all suspended interfaces are only resumed
1399 * to the device's state when @udev is root-hub and its suspend method
1400 * returns failure.
1401 *
1402 * Autosuspend requests originating from a child device or an interface
1403 * driver may be made without the protection of @udev's device lock, but
1404 * all other suspend calls will hold the lock. Usbcore will insure that
1405 * method calls do not arrive during bind, unbind, or reset operations.
1406 * However drivers must be prepared to handle suspend calls arriving at
1407 * unpredictable times.
1408 *
1409 * This routine can run only in process context.
1410 *
1411 * Return: 0 if the suspend succeeded.
1412 */
1413static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1414{
1415 int status = 0;
1416 int i = 0, n = 0;
1417 struct usb_interface *intf;
1418
1419 if (udev->state == USB_STATE_NOTATTACHED ||
1420 udev->state == USB_STATE_SUSPENDED)
1421 goto done;
1422
1423 if (msg.event == PM_EVENT_SUSPEND && usb_offload_check(udev)) {
1424 dev_dbg(&udev->dev, "device offloaded, skip suspend.\n");
1425 udev->offload_at_suspend = 1;
1426 }
1427
1428 /* Suspend all the interfaces and then udev itself */
1429 if (udev->actconfig) {
1430 n = udev->actconfig->desc.bNumInterfaces;
1431 for (i = n - 1; i >= 0; --i) {
1432 intf = udev->actconfig->interface[i];
1433 /*
1434 * Don't suspend interfaces with remote wakeup while
1435 * the controller is active. This preserves pending
1436 * interrupt urbs, allowing interrupt events to be
1437 * handled during system suspend.
1438 */
1439 if (udev->offload_at_suspend &&
1440 intf->needs_remote_wakeup) {
1441 dev_dbg(&intf->dev,
1442 "device offloaded, skip suspend.\n");
1443 continue;
1444 }
1445 status = usb_suspend_interface(udev, intf, msg);
1446
1447 /* Ignore errors during system sleep transitions */
1448 if (!PMSG_IS_AUTO(msg))
1449 status = 0;
1450 if (status != 0)
1451 break;
1452 }
1453 }
1454 if (status == 0) {
1455 if (!udev->offload_at_suspend)
1456 status = usb_suspend_device(udev, msg);
1457
1458 /*
1459 * Ignore errors from non-root-hub devices during
1460 * system sleep transitions. For the most part,
1461 * these devices should go to low power anyway when
1462 * the entire bus is suspended.
1463 */
1464 if (udev->parent && !PMSG_IS_AUTO(msg))
1465 status = 0;
1466
1467 /*
1468 * If the device is inaccessible, don't try to resume
1469 * suspended interfaces and just return the error.
1470 */
1471 if (status && status != -EBUSY) {
1472 int err;
1473 u16 devstat;
1474
1475 err = usb_get_std_status(dev: udev, USB_RECIP_DEVICE, target: 0,
1476 data: &devstat);
1477 if (err) {
1478 dev_err(&udev->dev,
1479 "Failed to suspend device, error %d\n",
1480 status);
1481 goto done;
1482 }
1483 }
1484 }
1485
1486 /* If the suspend failed, resume interfaces that did get suspended */
1487 if (status != 0) {
1488 if (udev->actconfig) {
1489 msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1490 while (++i < n) {
1491 intf = udev->actconfig->interface[i];
1492 usb_resume_interface(udev, intf, msg, reset_resume: 0);
1493 }
1494 }
1495
1496 /* If the suspend succeeded then prevent any more URB submissions
1497 * and flush any outstanding URBs.
1498 */
1499 } else {
1500 udev->can_submit = 0;
1501 if (!udev->offload_at_suspend) {
1502 for (i = 0; i < 16; ++i) {
1503 usb_hcd_flush_endpoint(udev, ep: udev->ep_out[i]);
1504 usb_hcd_flush_endpoint(udev, ep: udev->ep_in[i]);
1505 }
1506 }
1507 }
1508
1509 done:
1510 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1511 return status;
1512}
1513
1514/**
1515 * usb_resume_both - resume a USB device and its interfaces
1516 * @udev: the usb_device to resume
1517 * @msg: Power Management message describing this state transition
1518 *
1519 * This is the central routine for resuming USB devices. It calls the
1520 * resume method for @udev and then calls the resume methods for all
1521 * the interface drivers in @udev.
1522 *
1523 * Autoresume requests originating from a child device or an interface
1524 * driver may be made without the protection of @udev's device lock, but
1525 * all other resume calls will hold the lock. Usbcore will insure that
1526 * method calls do not arrive during bind, unbind, or reset operations.
1527 * However drivers must be prepared to handle resume calls arriving at
1528 * unpredictable times.
1529 *
1530 * This routine can run only in process context.
1531 *
1532 * Return: 0 on success.
1533 */
1534static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1535{
1536 int status = 0;
1537 int i;
1538 struct usb_interface *intf;
1539
1540 if (udev->state == USB_STATE_NOTATTACHED) {
1541 status = -ENODEV;
1542 goto done;
1543 }
1544 udev->can_submit = 1;
1545
1546 /* Resume the device */
1547 if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) {
1548 if (!udev->offload_at_suspend)
1549 status = usb_resume_device(udev, msg);
1550 else
1551 dev_dbg(&udev->dev,
1552 "device offloaded, skip resume.\n");
1553 }
1554
1555 /* Resume the interfaces */
1556 if (status == 0 && udev->actconfig) {
1557 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1558 intf = udev->actconfig->interface[i];
1559 /*
1560 * Interfaces with remote wakeup aren't suspended
1561 * while the controller is active. This preserves
1562 * pending interrupt urbs, allowing interrupt events
1563 * to be handled during system suspend.
1564 */
1565 if (udev->offload_at_suspend &&
1566 intf->needs_remote_wakeup) {
1567 dev_dbg(&intf->dev,
1568 "device offloaded, skip resume.\n");
1569 continue;
1570 }
1571 usb_resume_interface(udev, intf, msg,
1572 reset_resume: udev->reset_resume);
1573 }
1574 }
1575 udev->offload_at_suspend = 0;
1576 usb_mark_last_busy(udev);
1577
1578 done:
1579 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1580 if (!status)
1581 udev->reset_resume = 0;
1582 return status;
1583}
1584
1585static void choose_wakeup(struct usb_device *udev, pm_message_t msg)
1586{
1587 int w;
1588
1589 /*
1590 * For FREEZE/QUIESCE, disable remote wakeups so no interrupts get
1591 * generated.
1592 */
1593 if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
1594 w = 0;
1595
1596 } else {
1597 /*
1598 * Enable remote wakeup if it is allowed, even if no interface
1599 * drivers actually want it.
1600 */
1601 w = device_may_wakeup(dev: &udev->dev);
1602 }
1603
1604 /*
1605 * If the device is autosuspended with the wrong wakeup setting,
1606 * autoresume now so the setting can be changed.
1607 */
1608 if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup)
1609 pm_runtime_resume(dev: &udev->dev);
1610 udev->do_remote_wakeup = w;
1611}
1612
1613/* The device lock is held by the PM core */
1614int usb_suspend(struct device *dev, pm_message_t msg)
1615{
1616 struct usb_device *udev = to_usb_device(dev);
1617 int r;
1618
1619 unbind_no_pm_drivers_interfaces(udev);
1620
1621 /* From now on we are sure all drivers support suspend/resume
1622 * but not necessarily reset_resume()
1623 * so we may still need to unbind and rebind upon resume
1624 */
1625 choose_wakeup(udev, msg);
1626 r = usb_suspend_both(udev, msg);
1627 if (r)
1628 return r;
1629
1630 if (udev->quirks & USB_QUIRK_DISCONNECT_SUSPEND)
1631 usb_port_disable(udev);
1632
1633 return 0;
1634}
1635
1636/* The device lock is held by the PM core */
1637int usb_resume_complete(struct device *dev)
1638{
1639 struct usb_device *udev = to_usb_device(dev);
1640
1641 /* For PM complete calls, all we do is rebind interfaces
1642 * whose needs_binding flag is set
1643 */
1644 if (udev->state != USB_STATE_NOTATTACHED)
1645 rebind_marked_interfaces(udev);
1646 return 0;
1647}
1648
1649/* The device lock is held by the PM core */
1650int usb_resume(struct device *dev, pm_message_t msg)
1651{
1652 struct usb_device *udev = to_usb_device(dev);
1653 int status;
1654
1655 /* For all calls, take the device back to full power and
1656 * tell the PM core in case it was autosuspended previously.
1657 * Unbind the interfaces that will need rebinding later,
1658 * because they fail to support reset_resume.
1659 * (This can't be done in usb_resume_interface()
1660 * above because it doesn't own the right set of locks.)
1661 */
1662 status = usb_resume_both(udev, msg);
1663 if (status == 0) {
1664 pm_runtime_disable(dev);
1665 pm_runtime_set_active(dev);
1666 pm_runtime_enable(dev);
1667 unbind_marked_interfaces(udev);
1668 }
1669
1670 /* Avoid PM error messages for devices disconnected while suspended
1671 * as we'll display regular disconnect messages just a bit later.
1672 */
1673 if (status == -ENODEV || status == -ESHUTDOWN)
1674 status = 0;
1675 return status;
1676}
1677
1678/**
1679 * usb_enable_autosuspend - allow a USB device to be autosuspended
1680 * @udev: the USB device which may be autosuspended
1681 *
1682 * This routine allows @udev to be autosuspended. An autosuspend won't
1683 * take place until the autosuspend_delay has elapsed and all the other
1684 * necessary conditions are satisfied.
1685 *
1686 * The caller must hold @udev's device lock.
1687 */
1688void usb_enable_autosuspend(struct usb_device *udev)
1689{
1690 pm_runtime_allow(dev: &udev->dev);
1691}
1692EXPORT_SYMBOL_GPL(usb_enable_autosuspend);
1693
1694/**
1695 * usb_disable_autosuspend - prevent a USB device from being autosuspended
1696 * @udev: the USB device which may not be autosuspended
1697 *
1698 * This routine prevents @udev from being autosuspended and wakes it up
1699 * if it is already autosuspended.
1700 *
1701 * The caller must hold @udev's device lock.
1702 */
1703void usb_disable_autosuspend(struct usb_device *udev)
1704{
1705 pm_runtime_forbid(dev: &udev->dev);
1706}
1707EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
1708
1709/**
1710 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1711 * @udev: the usb_device to autosuspend
1712 *
1713 * This routine should be called when a core subsystem is finished using
1714 * @udev and wants to allow it to autosuspend. Examples would be when
1715 * @udev's device file in usbfs is closed or after a configuration change.
1716 *
1717 * @udev's usage counter is decremented; if it drops to 0 and all the
1718 * interfaces are inactive then a delayed autosuspend will be attempted.
1719 * The attempt may fail (see autosuspend_check()).
1720 *
1721 * The caller must hold @udev's device lock.
1722 *
1723 * This routine can run only in process context.
1724 */
1725void usb_autosuspend_device(struct usb_device *udev)
1726{
1727 int status;
1728
1729 usb_mark_last_busy(udev);
1730 status = pm_runtime_put_sync_autosuspend(dev: &udev->dev);
1731 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1732 __func__, atomic_read(&udev->dev.power.usage_count),
1733 status);
1734}
1735
1736/**
1737 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1738 * @udev: the usb_device to autoresume
1739 *
1740 * This routine should be called when a core subsystem wants to use @udev
1741 * and needs to guarantee that it is not suspended. No autosuspend will
1742 * occur until usb_autosuspend_device() is called. (Note that this will
1743 * not prevent suspend events originating in the PM core.) Examples would
1744 * be when @udev's device file in usbfs is opened or when a remote-wakeup
1745 * request is received.
1746 *
1747 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1748 * However if the autoresume fails then the usage counter is re-decremented.
1749 *
1750 * The caller must hold @udev's device lock.
1751 *
1752 * This routine can run only in process context.
1753 *
1754 * Return: 0 on success. A negative error code otherwise.
1755 */
1756int usb_autoresume_device(struct usb_device *udev)
1757{
1758 int status;
1759
1760 status = pm_runtime_resume_and_get(dev: &udev->dev);
1761 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1762 __func__, atomic_read(&udev->dev.power.usage_count),
1763 status);
1764 return status;
1765}
1766
1767/**
1768 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1769 * @intf: the usb_interface whose counter should be decremented
1770 *
1771 * This routine should be called by an interface driver when it is
1772 * finished using @intf and wants to allow it to autosuspend. A typical
1773 * example would be a character-device driver when its device file is
1774 * closed.
1775 *
1776 * The routine decrements @intf's usage counter. When the counter reaches
1777 * 0, a delayed autosuspend request for @intf's device is attempted. The
1778 * attempt may fail (see autosuspend_check()).
1779 *
1780 * This routine can run only in process context.
1781 */
1782void usb_autopm_put_interface(struct usb_interface *intf)
1783{
1784 struct usb_device *udev = interface_to_usbdev(intf);
1785 int status;
1786
1787 usb_mark_last_busy(udev);
1788 status = pm_runtime_put_sync(dev: &intf->dev);
1789 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1790 __func__, atomic_read(&intf->dev.power.usage_count),
1791 status);
1792}
1793EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1794
1795/**
1796 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1797 * @intf: the usb_interface whose counter should be decremented
1798 *
1799 * This routine does much the same thing as usb_autopm_put_interface():
1800 * It decrements @intf's usage counter and schedules a delayed
1801 * autosuspend request if the counter is <= 0. The difference is that it
1802 * does not perform any synchronization; callers should hold a private
1803 * lock and handle all synchronization issues themselves.
1804 *
1805 * Typically a driver would call this routine during an URB's completion
1806 * handler, if no more URBs were pending.
1807 *
1808 * This routine can run in atomic context.
1809 */
1810void usb_autopm_put_interface_async(struct usb_interface *intf)
1811{
1812 struct usb_device *udev = interface_to_usbdev(intf);
1813 int status;
1814
1815 usb_mark_last_busy(udev);
1816 status = pm_runtime_put(dev: &intf->dev);
1817 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1818 __func__, atomic_read(&intf->dev.power.usage_count),
1819 status);
1820}
1821EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1822
1823/**
1824 * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
1825 * @intf: the usb_interface whose counter should be decremented
1826 *
1827 * This routine decrements @intf's usage counter but does not carry out an
1828 * autosuspend.
1829 *
1830 * This routine can run in atomic context.
1831 */
1832void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
1833{
1834 struct usb_device *udev = interface_to_usbdev(intf);
1835
1836 usb_mark_last_busy(udev);
1837 pm_runtime_put_noidle(dev: &intf->dev);
1838}
1839EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
1840
1841/**
1842 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1843 * @intf: the usb_interface whose counter should be incremented
1844 *
1845 * This routine should be called by an interface driver when it wants to
1846 * use @intf and needs to guarantee that it is not suspended. In addition,
1847 * the routine prevents @intf from being autosuspended subsequently. (Note
1848 * that this will not prevent suspend events originating in the PM core.)
1849 * This prevention will persist until usb_autopm_put_interface() is called
1850 * or @intf is unbound. A typical example would be a character-device
1851 * driver when its device file is opened.
1852 *
1853 * @intf's usage counter is incremented to prevent subsequent autosuspends.
1854 * However if the autoresume fails then the counter is re-decremented.
1855 *
1856 * This routine can run only in process context.
1857 *
1858 * Return: 0 on success.
1859 */
1860int usb_autopm_get_interface(struct usb_interface *intf)
1861{
1862 int status;
1863
1864 status = pm_runtime_resume_and_get(dev: &intf->dev);
1865 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1866 __func__, atomic_read(&intf->dev.power.usage_count),
1867 status);
1868 return status;
1869}
1870EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1871
1872/**
1873 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1874 * @intf: the usb_interface whose counter should be incremented
1875 *
1876 * This routine does much the same thing as
1877 * usb_autopm_get_interface(): It increments @intf's usage counter and
1878 * queues an autoresume request if the device is suspended. The
1879 * differences are that it does not perform any synchronization (callers
1880 * should hold a private lock and handle all synchronization issues
1881 * themselves), and it does not autoresume the device directly (it only
1882 * queues a request). After a successful call, the device may not yet be
1883 * resumed.
1884 *
1885 * This routine can run in atomic context.
1886 *
1887 * Return: 0 on success. A negative error code otherwise.
1888 */
1889int usb_autopm_get_interface_async(struct usb_interface *intf)
1890{
1891 int status;
1892
1893 status = pm_runtime_get(dev: &intf->dev);
1894 if (status < 0 && status != -EINPROGRESS)
1895 pm_runtime_put_noidle(dev: &intf->dev);
1896 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1897 __func__, atomic_read(&intf->dev.power.usage_count),
1898 status);
1899 if (status > 0 || status == -EINPROGRESS)
1900 status = 0;
1901 return status;
1902}
1903EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1904
1905/**
1906 * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
1907 * @intf: the usb_interface whose counter should be incremented
1908 *
1909 * This routine increments @intf's usage counter but does not carry out an
1910 * autoresume.
1911 *
1912 * This routine can run in atomic context.
1913 */
1914void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
1915{
1916 struct usb_device *udev = interface_to_usbdev(intf);
1917
1918 usb_mark_last_busy(udev);
1919 pm_runtime_get_noresume(dev: &intf->dev);
1920}
1921EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
1922
1923/* Internal routine to check whether we may autosuspend a device. */
1924static int autosuspend_check(struct usb_device *udev)
1925{
1926 int w, i;
1927 struct usb_interface *intf;
1928
1929 if (udev->state == USB_STATE_NOTATTACHED)
1930 return -ENODEV;
1931
1932 /* Fail if autosuspend is disabled, or any interfaces are in use, or
1933 * any interface drivers require remote wakeup but it isn't available.
1934 */
1935 w = 0;
1936 if (udev->actconfig) {
1937 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1938 intf = udev->actconfig->interface[i];
1939
1940 /* We don't need to check interfaces that are
1941 * disabled for runtime PM. Either they are unbound
1942 * or else their drivers don't support autosuspend
1943 * and so they are permanently active.
1944 */
1945 if (intf->dev.power.disable_depth)
1946 continue;
1947 if (atomic_read(v: &intf->dev.power.usage_count) > 0)
1948 return -EBUSY;
1949 w |= intf->needs_remote_wakeup;
1950
1951 /* Don't allow autosuspend if the device will need
1952 * a reset-resume and any of its interface drivers
1953 * doesn't include support or needs remote wakeup.
1954 */
1955 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1956 struct usb_driver *driver;
1957
1958 driver = to_usb_driver(intf->dev.driver);
1959 if (!driver->reset_resume ||
1960 intf->needs_remote_wakeup)
1961 return -EOPNOTSUPP;
1962 }
1963 }
1964 }
1965 if (w && !device_can_wakeup(dev: &udev->dev)) {
1966 dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
1967 return -EOPNOTSUPP;
1968 }
1969
1970 /*
1971 * If the device is a direct child of the root hub and the HCD
1972 * doesn't handle wakeup requests, don't allow autosuspend when
1973 * wakeup is needed.
1974 */
1975 if (w && udev->parent == udev->bus->root_hub &&
1976 bus_to_hcd(bus: udev->bus)->cant_recv_wakeups) {
1977 dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\n");
1978 return -EOPNOTSUPP;
1979 }
1980
1981 udev->do_remote_wakeup = w;
1982 return 0;
1983}
1984
1985int usb_runtime_suspend(struct device *dev)
1986{
1987 struct usb_device *udev = to_usb_device(dev);
1988 int status;
1989
1990 /* A USB device can be suspended if it passes the various autosuspend
1991 * checks. Runtime suspend for a USB device means suspending all the
1992 * interfaces and then the device itself.
1993 */
1994 if (autosuspend_check(udev) != 0)
1995 return -EAGAIN;
1996
1997 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1998
1999 /* Allow a retry if autosuspend failed temporarily */
2000 if (status == -EAGAIN || status == -EBUSY)
2001 usb_mark_last_busy(udev);
2002
2003 /*
2004 * The PM core reacts badly unless the return code is 0,
2005 * -EAGAIN, or -EBUSY, so always return -EBUSY on an error
2006 * (except for root hubs, because they don't suspend through
2007 * an upstream port like other USB devices).
2008 */
2009 if (status != 0 && udev->parent)
2010 return -EBUSY;
2011 return status;
2012}
2013
2014int usb_runtime_resume(struct device *dev)
2015{
2016 struct usb_device *udev = to_usb_device(dev);
2017 int status;
2018
2019 /* Runtime resume for a USB device means resuming both the device
2020 * and all its interfaces.
2021 */
2022 status = usb_resume_both(udev, PMSG_AUTO_RESUME);
2023 return status;
2024}
2025
2026int usb_runtime_idle(struct device *dev)
2027{
2028 struct usb_device *udev = to_usb_device(dev);
2029
2030 /* An idle USB device can be suspended if it passes the various
2031 * autosuspend checks.
2032 */
2033 if (autosuspend_check(udev) == 0)
2034 pm_runtime_autosuspend(dev);
2035 /* Tell the core not to suspend it, though. */
2036 return -EBUSY;
2037}
2038
2039static int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
2040{
2041 struct usb_hcd *hcd = bus_to_hcd(bus: udev->bus);
2042 int ret = -EPERM;
2043
2044 if (hcd->driver->set_usb2_hw_lpm) {
2045 ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable);
2046 if (!ret)
2047 udev->usb2_hw_lpm_enabled = enable;
2048 }
2049
2050 return ret;
2051}
2052
2053int usb_enable_usb2_hardware_lpm(struct usb_device *udev)
2054{
2055 if (!udev->usb2_hw_lpm_capable ||
2056 !udev->usb2_hw_lpm_allowed ||
2057 udev->usb2_hw_lpm_enabled)
2058 return 0;
2059
2060 return usb_set_usb2_hardware_lpm(udev, enable: 1);
2061}
2062
2063int usb_disable_usb2_hardware_lpm(struct usb_device *udev)
2064{
2065 if (!udev->usb2_hw_lpm_enabled)
2066 return 0;
2067
2068 return usb_set_usb2_hardware_lpm(udev, enable: 0);
2069}
2070
2071#endif /* CONFIG_PM */
2072
2073const struct bus_type usb_bus_type = {
2074 .name = "usb",
2075 .match = usb_device_match,
2076 .uevent = usb_uevent,
2077 .need_parent_lock = true,
2078};
2079