2 * drivers/usb/driver.c - most of the driver model stuff for usb
4 * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
6 * based on drivers/usb/usb.c which had the following copyrights:
7 * (C) Copyright Linus Torvalds 1999
8 * (C) Copyright Johannes Erdfelt 1999-2001
9 * (C) Copyright Andreas Gal 1999
10 * (C) Copyright Gregory P. Smith 1999
11 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
12 * (C) Copyright Randy Dunlap 2000
13 * (C) Copyright David Brownell 2000-2004
14 * (C) Copyright Yggdrasil Computing, Inc. 2000
15 * (usb_device_id matching changes by Adam J. Richter)
16 * (C) Copyright Greg Kroah-Hartman 2002-2003
18 * NOTE! This is not actually a driver at all, rather this is
19 * just a collection of helper routines that implement the
20 * matching, probing, releasing, suspending and resuming for
25 #include <linux/device.h>
26 #include <linux/usb.h>
27 #include <linux/usb/quirks.h>
28 #include <linux/workqueue.h>
36 * Adds a new dynamic USBdevice ID to this driver,
37 * and cause the driver to probe for all devices again.
39 ssize_t usb_store_new_id(struct usb_dynids *dynids,
40 struct device_driver *driver,
41 const char *buf, size_t count)
43 struct usb_dynid *dynid;
49 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
53 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
57 INIT_LIST_HEAD(&dynid->node);
58 dynid->id.idVendor = idVendor;
59 dynid->id.idProduct = idProduct;
60 dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
62 spin_lock(&dynids->lock);
63 list_add_tail(&dynid->node, &dynids->list);
64 spin_unlock(&dynids->lock);
66 if (get_driver(driver)) {
67 retval = driver_attach(driver);
75 EXPORT_SYMBOL_GPL(usb_store_new_id);
77 static ssize_t store_new_id(struct device_driver *driver,
78 const char *buf, size_t count)
80 struct usb_driver *usb_drv = to_usb_driver(driver);
82 return usb_store_new_id(&usb_drv->dynids, driver, buf, count);
84 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
86 static int usb_create_newid_file(struct usb_driver *usb_drv)
90 if (usb_drv->no_dynamic_id)
93 if (usb_drv->probe != NULL)
94 error = driver_create_file(&usb_drv->drvwrap.driver,
100 static void usb_remove_newid_file(struct usb_driver *usb_drv)
102 if (usb_drv->no_dynamic_id)
105 if (usb_drv->probe != NULL)
106 driver_remove_file(&usb_drv->drvwrap.driver,
107 &driver_attr_new_id);
110 static void usb_free_dynids(struct usb_driver *usb_drv)
112 struct usb_dynid *dynid, *n;
114 spin_lock(&usb_drv->dynids.lock);
115 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
116 list_del(&dynid->node);
119 spin_unlock(&usb_drv->dynids.lock);
122 static inline int usb_create_newid_file(struct usb_driver *usb_drv)
127 static void usb_remove_newid_file(struct usb_driver *usb_drv)
131 static inline void usb_free_dynids(struct usb_driver *usb_drv)
136 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
137 struct usb_driver *drv)
139 struct usb_dynid *dynid;
141 spin_lock(&drv->dynids.lock);
142 list_for_each_entry(dynid, &drv->dynids.list, node) {
143 if (usb_match_one_id(intf, &dynid->id)) {
144 spin_unlock(&drv->dynids.lock);
148 spin_unlock(&drv->dynids.lock);
153 /* called from driver core with dev locked */
154 static int usb_probe_device(struct device *dev)
156 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
157 struct usb_device *udev;
160 dev_dbg(dev, "%s\n", __func__);
162 if (!is_usb_device(dev)) /* Sanity check */
165 udev = to_usb_device(dev);
167 /* TODO: Add real matching code */
169 /* The device should always appear to be in use
170 * unless the driver suports autosuspend.
172 udev->pm_usage_cnt = !(udriver->supports_autosuspend);
174 error = udriver->probe(udev);
178 /* called from driver core with dev locked */
179 static int usb_unbind_device(struct device *dev)
181 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
183 udriver->disconnect(to_usb_device(dev));
188 /* called from driver core with dev locked */
189 static int usb_probe_interface(struct device *dev)
191 struct usb_driver *driver = to_usb_driver(dev->driver);
192 struct usb_interface *intf;
193 struct usb_device *udev;
194 const struct usb_device_id *id;
197 dev_dbg(dev, "%s\n", __func__);
199 if (is_usb_device(dev)) /* Sanity check */
202 intf = to_usb_interface(dev);
203 udev = interface_to_usbdev(intf);
204 intf->needs_binding = 0;
206 if (udev->authorized == 0) {
207 dev_err(&intf->dev, "Device is not authorized for usage\n");
211 id = usb_match_id(intf, driver->id_table);
213 id = usb_match_dynamic_id(intf, driver);
215 dev_dbg(dev, "%s - got id\n", __func__);
217 error = usb_autoresume_device(udev);
221 /* Interface "power state" doesn't correspond to any hardware
222 * state whatsoever. We use it to record when it's bound to
223 * a driver that may start I/0: it's not frozen/quiesced.
226 intf->condition = USB_INTERFACE_BINDING;
228 /* The interface should always appear to be in use
229 * unless the driver suports autosuspend.
231 intf->pm_usage_cnt = !(driver->supports_autosuspend);
233 /* Carry out a deferred switch to altsetting 0 */
234 if (intf->needs_altsetting0) {
235 usb_set_interface(udev, intf->altsetting[0].
236 desc.bInterfaceNumber, 0);
237 intf->needs_altsetting0 = 0;
240 error = driver->probe(intf, id);
243 intf->needs_remote_wakeup = 0;
244 intf->condition = USB_INTERFACE_UNBOUND;
246 intf->condition = USB_INTERFACE_BOUND;
248 usb_autosuspend_device(udev);
254 /* called from driver core with dev locked */
255 static int usb_unbind_interface(struct device *dev)
257 struct usb_driver *driver = to_usb_driver(dev->driver);
258 struct usb_interface *intf = to_usb_interface(dev);
259 struct usb_device *udev;
262 intf->condition = USB_INTERFACE_UNBINDING;
264 /* Autoresume for set_interface call below */
265 udev = interface_to_usbdev(intf);
266 error = usb_autoresume_device(udev);
268 /* Terminate all URBs for this interface unless the driver
269 * supports "soft" unbinding.
271 if (!driver->soft_unbind)
272 usb_disable_interface(udev, intf);
274 driver->disconnect(intf);
276 /* Reset other interface state.
277 * We cannot do a Set-Interface if the device is suspended or
278 * if it is prepared for a system sleep (since installing a new
279 * altsetting means creating new endpoint device entries).
280 * When either of these happens, defer the Set-Interface.
282 if (!error && intf->dev.power.status == DPM_ON)
283 usb_set_interface(udev, intf->altsetting[0].
284 desc.bInterfaceNumber, 0);
286 intf->needs_altsetting0 = 1;
287 usb_set_intfdata(intf, NULL);
289 intf->condition = USB_INTERFACE_UNBOUND;
291 intf->needs_remote_wakeup = 0;
294 usb_autosuspend_device(udev);
300 * usb_driver_claim_interface - bind a driver to an interface
301 * @driver: the driver to be bound
302 * @iface: the interface to which it will be bound; must be in the
303 * usb device's active configuration
304 * @priv: driver data associated with that interface
306 * This is used by usb device drivers that need to claim more than one
307 * interface on a device when probing (audio and acm are current examples).
308 * No device driver should directly modify internal usb_interface or
309 * usb_device structure members.
311 * Few drivers should need to use this routine, since the most natural
312 * way to bind to an interface is to return the private data from
313 * the driver's probe() method.
315 * Callers must own the device lock, so driver probe() entries don't need
316 * extra locking, but other call contexts may need to explicitly claim that
319 int usb_driver_claim_interface(struct usb_driver *driver,
320 struct usb_interface *iface, void *priv)
322 struct device *dev = &iface->dev;
323 struct usb_device *udev = interface_to_usbdev(iface);
329 dev->driver = &driver->drvwrap.driver;
330 usb_set_intfdata(iface, priv);
331 iface->needs_binding = 0;
334 iface->condition = USB_INTERFACE_BOUND;
336 iface->pm_usage_cnt = !(driver->supports_autosuspend);
339 /* if interface was already added, bind now; else let
340 * the future device_add() bind it, bypassing probe()
342 if (device_is_registered(dev))
343 retval = device_bind_driver(dev);
347 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
350 * usb_driver_release_interface - unbind a driver from an interface
351 * @driver: the driver to be unbound
352 * @iface: the interface from which it will be unbound
354 * This can be used by drivers to release an interface without waiting
355 * for their disconnect() methods to be called. In typical cases this
356 * also causes the driver disconnect() method to be called.
358 * This call is synchronous, and may not be used in an interrupt context.
359 * Callers must own the device lock, so driver disconnect() entries don't
360 * need extra locking, but other call contexts may need to explicitly claim
363 void usb_driver_release_interface(struct usb_driver *driver,
364 struct usb_interface *iface)
366 struct device *dev = &iface->dev;
367 struct usb_device *udev = interface_to_usbdev(iface);
369 /* this should never happen, don't release something that's not ours */
370 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
373 /* don't release from within disconnect() */
374 if (iface->condition != USB_INTERFACE_BOUND)
377 /* don't release if the interface hasn't been added yet */
378 if (device_is_registered(dev)) {
379 iface->condition = USB_INTERFACE_UNBINDING;
380 device_release_driver(dev);
384 usb_set_intfdata(iface, NULL);
387 iface->condition = USB_INTERFACE_UNBOUND;
388 mark_quiesced(iface);
389 iface->needs_remote_wakeup = 0;
392 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
394 /* returns 0 if no match, 1 if match */
395 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
397 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
398 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
401 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
402 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
405 /* No need to test id->bcdDevice_lo != 0, since 0 is never
406 greater than any unsigned number. */
407 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
408 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
411 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
412 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
415 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
416 (id->bDeviceClass != dev->descriptor.bDeviceClass))
419 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
420 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
423 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
424 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
430 /* returns 0 if no match, 1 if match */
431 int usb_match_one_id(struct usb_interface *interface,
432 const struct usb_device_id *id)
434 struct usb_host_interface *intf;
435 struct usb_device *dev;
437 /* proc_connectinfo in devio.c may call us with id == NULL. */
441 intf = interface->cur_altsetting;
442 dev = interface_to_usbdev(interface);
444 if (!usb_match_device(dev, id))
447 /* The interface class, subclass, and protocol should never be
448 * checked for a match if the device class is Vendor Specific,
449 * unless the match record specifies the Vendor ID. */
450 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
451 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
452 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
453 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
454 USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
457 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
458 (id->bInterfaceClass != intf->desc.bInterfaceClass))
461 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
462 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
465 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
466 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
471 EXPORT_SYMBOL_GPL(usb_match_one_id);
474 * usb_match_id - find first usb_device_id matching device or interface
475 * @interface: the interface of interest
476 * @id: array of usb_device_id structures, terminated by zero entry
478 * usb_match_id searches an array of usb_device_id's and returns
479 * the first one matching the device or interface, or null.
480 * This is used when binding (or rebinding) a driver to an interface.
481 * Most USB device drivers will use this indirectly, through the usb core,
482 * but some layered driver frameworks use it directly.
483 * These device tables are exported with MODULE_DEVICE_TABLE, through
484 * modutils, to support the driver loading functionality of USB hotplugging.
488 * The "match_flags" element in a usb_device_id controls which
489 * members are used. If the corresponding bit is set, the
490 * value in the device_id must match its corresponding member
491 * in the device or interface descriptor, or else the device_id
494 * "driver_info" is normally used only by device drivers,
495 * but you can create a wildcard "matches anything" usb_device_id
496 * as a driver's "modules.usbmap" entry if you provide an id with
497 * only a nonzero "driver_info" field. If you do this, the USB device
498 * driver's probe() routine should use additional intelligence to
499 * decide whether to bind to the specified interface.
501 * What Makes Good usb_device_id Tables:
503 * The match algorithm is very simple, so that intelligence in
504 * driver selection must come from smart driver id records.
505 * Unless you have good reasons to use another selection policy,
506 * provide match elements only in related groups, and order match
507 * specifiers from specific to general. Use the macros provided
508 * for that purpose if you can.
510 * The most specific match specifiers use device descriptor
511 * data. These are commonly used with product-specific matches;
512 * the USB_DEVICE macro lets you provide vendor and product IDs,
513 * and you can also match against ranges of product revisions.
514 * These are widely used for devices with application or vendor
515 * specific bDeviceClass values.
517 * Matches based on device class/subclass/protocol specifications
518 * are slightly more general; use the USB_DEVICE_INFO macro, or
519 * its siblings. These are used with single-function devices
520 * where bDeviceClass doesn't specify that each interface has
523 * Matches based on interface class/subclass/protocol are the
524 * most general; they let drivers bind to any interface on a
525 * multiple-function device. Use the USB_INTERFACE_INFO
526 * macro, or its siblings, to match class-per-interface style
527 * devices (as recorded in bInterfaceClass).
529 * Note that an entry created by USB_INTERFACE_INFO won't match
530 * any interface if the device class is set to Vendor-Specific.
531 * This is deliberate; according to the USB spec the meanings of
532 * the interface class/subclass/protocol for these devices are also
533 * vendor-specific, and hence matching against a standard product
534 * class wouldn't work anyway. If you really want to use an
535 * interface-based match for such a device, create a match record
536 * that also specifies the vendor ID. (Unforunately there isn't a
537 * standard macro for creating records like this.)
539 * Within those groups, remember that not all combinations are
540 * meaningful. For example, don't give a product version range
541 * without vendor and product IDs; or specify a protocol without
542 * its associated class and subclass.
544 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
545 const struct usb_device_id *id)
547 /* proc_connectinfo in devio.c may call us with id == NULL. */
551 /* It is important to check that id->driver_info is nonzero,
552 since an entry that is all zeroes except for a nonzero
553 id->driver_info is the way to create an entry that
554 indicates that the driver want to examine every
555 device and interface. */
556 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
557 id->bInterfaceClass || id->driver_info; id++) {
558 if (usb_match_one_id(interface, id))
564 EXPORT_SYMBOL_GPL(usb_match_id);
566 static int usb_device_match(struct device *dev, struct device_driver *drv)
568 /* devices and interfaces are handled separately */
569 if (is_usb_device(dev)) {
571 /* interface drivers never match devices */
572 if (!is_usb_device_driver(drv))
575 /* TODO: Add real matching code */
579 struct usb_interface *intf;
580 struct usb_driver *usb_drv;
581 const struct usb_device_id *id;
583 /* device drivers never match interfaces */
584 if (is_usb_device_driver(drv))
587 intf = to_usb_interface(dev);
588 usb_drv = to_usb_driver(drv);
590 id = usb_match_id(intf, usb_drv->id_table);
594 id = usb_match_dynamic_id(intf, usb_drv);
602 #ifdef CONFIG_HOTPLUG
603 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
605 struct usb_device *usb_dev;
607 /* driver is often null here; dev_dbg() would oops */
608 pr_debug("usb %s: uevent\n", dev_name(dev));
610 if (is_usb_device(dev))
611 usb_dev = to_usb_device(dev);
613 struct usb_interface *intf = to_usb_interface(dev);
614 usb_dev = interface_to_usbdev(intf);
617 if (usb_dev->devnum < 0) {
618 pr_debug("usb %s: already deleted?\n", dev_name(dev));
622 pr_debug("usb %s: bus removed?\n", dev_name(dev));
626 #ifdef CONFIG_USB_DEVICEFS
627 /* If this is available, userspace programs can directly read
628 * all the device descriptors we don't tell them about. Or
629 * act as usermode drivers.
631 if (add_uevent_var(env, "DEVICE=/proc/bus/usb/%03d/%03d",
632 usb_dev->bus->busnum, usb_dev->devnum))
636 /* per-device configurations are common */
637 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
638 le16_to_cpu(usb_dev->descriptor.idVendor),
639 le16_to_cpu(usb_dev->descriptor.idProduct),
640 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
643 /* class-based driver binding models */
644 if (add_uevent_var(env, "TYPE=%d/%d/%d",
645 usb_dev->descriptor.bDeviceClass,
646 usb_dev->descriptor.bDeviceSubClass,
647 usb_dev->descriptor.bDeviceProtocol))
655 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
659 #endif /* CONFIG_HOTPLUG */
662 * usb_register_device_driver - register a USB device (not interface) driver
663 * @new_udriver: USB operations for the device driver
664 * @owner: module owner of this driver.
666 * Registers a USB device driver with the USB core. The list of
667 * unattached devices will be rescanned whenever a new driver is
668 * added, allowing the new driver to attach to any recognized devices.
669 * Returns a negative error code on failure and 0 on success.
671 int usb_register_device_driver(struct usb_device_driver *new_udriver,
672 struct module *owner)
679 new_udriver->drvwrap.for_devices = 1;
680 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
681 new_udriver->drvwrap.driver.bus = &usb_bus_type;
682 new_udriver->drvwrap.driver.probe = usb_probe_device;
683 new_udriver->drvwrap.driver.remove = usb_unbind_device;
684 new_udriver->drvwrap.driver.owner = owner;
686 retval = driver_register(&new_udriver->drvwrap.driver);
689 pr_info("%s: registered new device driver %s\n",
690 usbcore_name, new_udriver->name);
691 usbfs_update_special();
693 printk(KERN_ERR "%s: error %d registering device "
695 usbcore_name, retval, new_udriver->name);
700 EXPORT_SYMBOL_GPL(usb_register_device_driver);
703 * usb_deregister_device_driver - unregister a USB device (not interface) driver
704 * @udriver: USB operations of the device driver to unregister
705 * Context: must be able to sleep
707 * Unlinks the specified driver from the internal USB driver list.
709 void usb_deregister_device_driver(struct usb_device_driver *udriver)
711 pr_info("%s: deregistering device driver %s\n",
712 usbcore_name, udriver->name);
714 driver_unregister(&udriver->drvwrap.driver);
715 usbfs_update_special();
717 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
720 * usb_register_driver - register a USB interface driver
721 * @new_driver: USB operations for the interface driver
722 * @owner: module owner of this driver.
723 * @mod_name: module name string
725 * Registers a USB interface driver with the USB core. The list of
726 * unattached interfaces will be rescanned whenever a new driver is
727 * added, allowing the new driver to attach to any recognized interfaces.
728 * Returns a negative error code on failure and 0 on success.
730 * NOTE: if you want your driver to use the USB major number, you must call
731 * usb_register_dev() to enable that functionality. This function no longer
732 * takes care of that.
734 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
735 const char *mod_name)
742 new_driver->drvwrap.for_devices = 0;
743 new_driver->drvwrap.driver.name = (char *) new_driver->name;
744 new_driver->drvwrap.driver.bus = &usb_bus_type;
745 new_driver->drvwrap.driver.probe = usb_probe_interface;
746 new_driver->drvwrap.driver.remove = usb_unbind_interface;
747 new_driver->drvwrap.driver.owner = owner;
748 new_driver->drvwrap.driver.mod_name = mod_name;
749 spin_lock_init(&new_driver->dynids.lock);
750 INIT_LIST_HEAD(&new_driver->dynids.list);
752 retval = driver_register(&new_driver->drvwrap.driver);
755 pr_info("%s: registered new interface driver %s\n",
756 usbcore_name, new_driver->name);
757 usbfs_update_special();
758 usb_create_newid_file(new_driver);
760 printk(KERN_ERR "%s: error %d registering interface "
762 usbcore_name, retval, new_driver->name);
767 EXPORT_SYMBOL_GPL(usb_register_driver);
770 * usb_deregister - unregister a USB interface driver
771 * @driver: USB operations of the interface driver to unregister
772 * Context: must be able to sleep
774 * Unlinks the specified driver from the internal USB driver list.
776 * NOTE: If you called usb_register_dev(), you still need to call
777 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
778 * this * call will no longer do it for you.
780 void usb_deregister(struct usb_driver *driver)
782 pr_info("%s: deregistering interface driver %s\n",
783 usbcore_name, driver->name);
785 usb_remove_newid_file(driver);
786 usb_free_dynids(driver);
787 driver_unregister(&driver->drvwrap.driver);
789 usbfs_update_special();
791 EXPORT_SYMBOL_GPL(usb_deregister);
793 /* Forced unbinding of a USB interface driver, either because
794 * it doesn't support pre_reset/post_reset/reset_resume or
795 * because it doesn't support suspend/resume.
797 * The caller must hold @intf's device's lock, but not its pm_mutex
798 * and not @intf->dev.sem.
800 void usb_forced_unbind_intf(struct usb_interface *intf)
802 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
804 dev_dbg(&intf->dev, "forced unbind\n");
805 usb_driver_release_interface(driver, intf);
807 /* Mark the interface for later rebinding */
808 intf->needs_binding = 1;
811 /* Delayed forced unbinding of a USB interface driver and scan
814 * The caller must hold @intf's device's lock, but not its pm_mutex
815 * and not @intf->dev.sem.
817 * FIXME: The caller must block system sleep transitions.
819 void usb_rebind_intf(struct usb_interface *intf)
823 /* Delayed unbind of an existing driver */
824 if (intf->dev.driver) {
825 struct usb_driver *driver =
826 to_usb_driver(intf->dev.driver);
828 dev_dbg(&intf->dev, "forced unbind\n");
829 usb_driver_release_interface(driver, intf);
832 /* Try to rebind the interface */
833 intf->needs_binding = 0;
834 rc = device_attach(&intf->dev);
836 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
844 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
845 * or rebind interfaces that have been unbound, according to @action.
847 * The caller must hold @udev's device lock.
848 * FIXME: For rebinds, the caller must block system sleep transitions.
850 static void do_unbind_rebind(struct usb_device *udev, int action)
852 struct usb_host_config *config;
854 struct usb_interface *intf;
855 struct usb_driver *drv;
857 config = udev->actconfig;
859 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
860 intf = config->interface[i];
863 if (intf->dev.driver) {
864 drv = to_usb_driver(intf->dev.driver);
865 if (!drv->suspend || !drv->resume)
866 usb_forced_unbind_intf(intf);
870 if (intf->needs_binding) {
872 /* FIXME: The next line is needed because we are going to probe
873 * the interface, but as far as the PM core is concerned the
874 * interface is still suspended. The problem wouldn't exist
875 * if we could rebind the interface during the interface's own
876 * resume() call, but at the time the usb_device isn't locked!
878 * The real solution will be to carry this out during the device's
879 * complete() callback. Until that is implemented, we have to
882 // intf->dev.power.sleeping = 0;
884 usb_rebind_intf(intf);
892 /* Caller has locked udev's pm_mutex */
893 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
895 struct usb_device_driver *udriver;
898 if (udev->state == USB_STATE_NOTATTACHED ||
899 udev->state == USB_STATE_SUSPENDED)
902 /* For devices that don't have a driver, we do a generic suspend. */
903 if (udev->dev.driver)
904 udriver = to_usb_device_driver(udev->dev.driver);
906 udev->do_remote_wakeup = 0;
907 udriver = &usb_generic_driver;
909 status = udriver->suspend(udev, msg);
912 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
916 /* Caller has locked udev's pm_mutex */
917 static int usb_resume_device(struct usb_device *udev)
919 struct usb_device_driver *udriver;
922 if (udev->state == USB_STATE_NOTATTACHED)
925 /* Can't resume it if it doesn't have a driver. */
926 if (udev->dev.driver == NULL) {
931 if (udev->quirks & USB_QUIRK_RESET_RESUME)
932 udev->reset_resume = 1;
934 udriver = to_usb_device_driver(udev->dev.driver);
935 status = udriver->resume(udev);
938 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
940 udev->autoresume_disabled = 0;
944 /* Caller has locked intf's usb_device's pm mutex */
945 static int usb_suspend_interface(struct usb_device *udev,
946 struct usb_interface *intf, pm_message_t msg)
948 struct usb_driver *driver;
951 /* with no hardware, USB interfaces only use FREEZE and ON states */
952 if (udev->state == USB_STATE_NOTATTACHED || !is_active(intf))
955 if (intf->condition == USB_INTERFACE_UNBOUND) /* This can't happen */
957 driver = to_usb_driver(intf->dev.driver);
959 if (driver->suspend) {
960 status = driver->suspend(intf, msg);
963 else if (!udev->auto_pm)
964 dev_err(&intf->dev, "%s error %d\n",
967 /* Later we will unbind the driver and reprobe */
968 intf->needs_binding = 1;
969 dev_warn(&intf->dev, "no %s for driver %s?\n",
970 "suspend", driver->name);
975 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
979 /* Caller has locked intf's usb_device's pm_mutex */
980 static int usb_resume_interface(struct usb_device *udev,
981 struct usb_interface *intf, int reset_resume)
983 struct usb_driver *driver;
986 if (udev->state == USB_STATE_NOTATTACHED || is_active(intf))
989 /* Don't let autoresume interfere with unbinding */
990 if (intf->condition == USB_INTERFACE_UNBINDING)
993 /* Can't resume it if it doesn't have a driver. */
994 if (intf->condition == USB_INTERFACE_UNBOUND) {
996 /* Carry out a deferred switch to altsetting 0 */
997 if (intf->needs_altsetting0 &&
998 intf->dev.power.status == DPM_ON) {
999 usb_set_interface(udev, intf->altsetting[0].
1000 desc.bInterfaceNumber, 0);
1001 intf->needs_altsetting0 = 0;
1006 /* Don't resume if the interface is marked for rebinding */
1007 if (intf->needs_binding)
1009 driver = to_usb_driver(intf->dev.driver);
1012 if (driver->reset_resume) {
1013 status = driver->reset_resume(intf);
1015 dev_err(&intf->dev, "%s error %d\n",
1016 "reset_resume", status);
1018 intf->needs_binding = 1;
1019 dev_warn(&intf->dev, "no %s for driver %s?\n",
1020 "reset_resume", driver->name);
1023 if (driver->resume) {
1024 status = driver->resume(intf);
1026 dev_err(&intf->dev, "%s error %d\n",
1029 intf->needs_binding = 1;
1030 dev_warn(&intf->dev, "no %s for driver %s?\n",
1031 "resume", driver->name);
1036 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1037 if (status == 0 && intf->condition == USB_INTERFACE_BOUND)
1040 /* Later we will unbind the driver and/or reprobe, if necessary */
1044 #ifdef CONFIG_USB_SUSPEND
1046 /* Internal routine to check whether we may autosuspend a device. */
1047 static int autosuspend_check(struct usb_device *udev, int reschedule)
1050 struct usb_interface *intf;
1051 unsigned long suspend_time, j;
1053 /* For autosuspend, fail fast if anything is in use or autosuspend
1054 * is disabled. Also fail if any interfaces require remote wakeup
1055 * but it isn't available.
1057 if (udev->pm_usage_cnt > 0)
1059 if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
1062 suspend_time = udev->last_busy + udev->autosuspend_delay;
1063 if (udev->actconfig) {
1064 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1065 intf = udev->actconfig->interface[i];
1066 if (!is_active(intf))
1068 if (intf->pm_usage_cnt > 0)
1070 if (intf->needs_remote_wakeup &&
1071 !udev->do_remote_wakeup) {
1072 dev_dbg(&udev->dev, "remote wakeup needed "
1073 "for autosuspend\n");
1077 /* Don't allow autosuspend if the device will need
1078 * a reset-resume and any of its interface drivers
1079 * doesn't include support.
1081 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1082 struct usb_driver *driver;
1084 driver = to_usb_driver(intf->dev.driver);
1085 if (!driver->reset_resume)
1091 /* If everything is okay but the device hasn't been idle for long
1092 * enough, queue a delayed autosuspend request. If the device
1093 * _has_ been idle for long enough and the reschedule flag is set,
1094 * likewise queue a delayed (1 second) autosuspend request.
1097 if (time_before(j, suspend_time))
1100 suspend_time = j + HZ;
1102 if (!timer_pending(&udev->autosuspend.timer)) {
1103 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
1104 round_jiffies_relative(suspend_time - j));
1113 static inline int autosuspend_check(struct usb_device *udev, int reschedule)
1118 #endif /* CONFIG_USB_SUSPEND */
1121 * usb_suspend_both - suspend a USB device and its interfaces
1122 * @udev: the usb_device to suspend
1123 * @msg: Power Management message describing this state transition
1125 * This is the central routine for suspending USB devices. It calls the
1126 * suspend methods for all the interface drivers in @udev and then calls
1127 * the suspend method for @udev itself. If an error occurs at any stage,
1128 * all the interfaces which were suspended are resumed so that they remain
1129 * in the same state as the device.
1131 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
1132 * checks first to make sure that neither the device itself or any of its
1133 * active interfaces is in use (pm_usage_cnt is greater than 0). If they
1134 * are, the autosuspend fails.
1136 * If the suspend succeeds, the routine recursively queues an autosuspend
1137 * request for @udev's parent device, thereby propagating the change up
1138 * the device tree. If all of the parent's children are now suspended,
1139 * the parent will autosuspend in turn.
1141 * The suspend method calls are subject to mutual exclusion under control
1142 * of @udev's pm_mutex. Many of these calls are also under the protection
1143 * of @udev's device lock (including all requests originating outside the
1144 * USB subsystem), but autosuspend requests generated by a child device or
1145 * interface driver may not be. Usbcore will insure that the method calls
1146 * do not arrive during bind, unbind, or reset operations. However, drivers
1147 * must be prepared to handle suspend calls arriving at unpredictable times.
1148 * The only way to block such calls is to do an autoresume (preventing
1149 * autosuspends) while holding @udev's device lock (preventing outside
1152 * The caller must hold @udev->pm_mutex.
1154 * This routine can run only in process context.
1156 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1160 struct usb_interface *intf;
1161 struct usb_device *parent = udev->parent;
1163 if (udev->state == USB_STATE_NOTATTACHED ||
1164 udev->state == USB_STATE_SUSPENDED)
1167 udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
1169 if (udev->auto_pm) {
1170 status = autosuspend_check(udev, 0);
1175 /* Suspend all the interfaces and then udev itself */
1176 if (udev->actconfig) {
1177 for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
1178 intf = udev->actconfig->interface[i];
1179 status = usb_suspend_interface(udev, intf, msg);
1185 status = usb_suspend_device(udev, msg);
1187 /* If the suspend failed, resume interfaces that did get suspended */
1190 intf = udev->actconfig->interface[i];
1191 usb_resume_interface(udev, intf, 0);
1194 /* Try another autosuspend when the interfaces aren't busy */
1196 autosuspend_check(udev, status == -EBUSY);
1198 /* If the suspend succeeded then prevent any more URB submissions,
1199 * flush any outstanding URBs, and propagate the suspend up the tree.
1202 cancel_delayed_work(&udev->autosuspend);
1203 udev->can_submit = 0;
1204 for (i = 0; i < 16; ++i) {
1205 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1206 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1209 /* If this is just a FREEZE or a PRETHAW, udev might
1210 * not really be suspended. Only true suspends get
1211 * propagated up the device tree.
1213 if (parent && udev->state == USB_STATE_SUSPENDED)
1214 usb_autosuspend_device(parent);
1218 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1223 * usb_resume_both - resume a USB device and its interfaces
1224 * @udev: the usb_device to resume
1226 * This is the central routine for resuming USB devices. It calls the
1227 * the resume method for @udev and then calls the resume methods for all
1228 * the interface drivers in @udev.
1230 * Before starting the resume, the routine calls itself recursively for
1231 * the parent device of @udev, thereby propagating the change up the device
1232 * tree and assuring that @udev will be able to resume. If the parent is
1233 * unable to resume successfully, the routine fails.
1235 * The resume method calls are subject to mutual exclusion under control
1236 * of @udev's pm_mutex. Many of these calls are also under the protection
1237 * of @udev's device lock (including all requests originating outside the
1238 * USB subsystem), but autoresume requests generated by a child device or
1239 * interface driver may not be. Usbcore will insure that the method calls
1240 * do not arrive during bind, unbind, or reset operations. However, drivers
1241 * must be prepared to handle resume calls arriving at unpredictable times.
1242 * The only way to block such calls is to do an autoresume (preventing
1243 * other autoresumes) while holding @udev's device lock (preventing outside
1246 * The caller must hold @udev->pm_mutex.
1248 * This routine can run only in process context.
1250 static int usb_resume_both(struct usb_device *udev)
1254 struct usb_interface *intf;
1255 struct usb_device *parent = udev->parent;
1257 cancel_delayed_work(&udev->autosuspend);
1258 if (udev->state == USB_STATE_NOTATTACHED) {
1262 udev->can_submit = 1;
1264 /* Propagate the resume up the tree, if necessary */
1265 if (udev->state == USB_STATE_SUSPENDED) {
1266 if (udev->auto_pm && udev->autoresume_disabled) {
1271 status = usb_autoresume_device(parent);
1273 status = usb_resume_device(udev);
1274 if (status || udev->state ==
1275 USB_STATE_NOTATTACHED) {
1276 usb_autosuspend_device(parent);
1278 /* It's possible usb_resume_device()
1279 * failed after the port was
1280 * unsuspended, causing udev to be
1281 * logically disconnected. We don't
1282 * want usb_disconnect() to autosuspend
1283 * the parent again, so tell it that
1284 * udev disconnected while still
1287 USB_STATE_NOTATTACHED)
1288 udev->discon_suspended = 1;
1293 /* We can't progagate beyond the USB subsystem,
1294 * so if a root hub's controller is suspended
1295 * then we're stuck. */
1296 status = usb_resume_device(udev);
1298 } else if (udev->reset_resume)
1299 status = usb_resume_device(udev);
1301 if (status == 0 && udev->actconfig) {
1302 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1303 intf = udev->actconfig->interface[i];
1304 usb_resume_interface(udev, intf, udev->reset_resume);
1309 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1311 udev->reset_resume = 0;
1315 #ifdef CONFIG_USB_SUSPEND
1317 /* Internal routine to adjust a device's usage counter and change
1318 * its autosuspend state.
1320 static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
1326 udev->pm_usage_cnt += inc_usage_cnt;
1327 WARN_ON(udev->pm_usage_cnt < 0);
1329 udev->last_busy = jiffies;
1330 if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
1331 if (udev->state == USB_STATE_SUSPENDED)
1332 status = usb_resume_both(udev);
1334 udev->pm_usage_cnt -= inc_usage_cnt;
1335 else if (inc_usage_cnt)
1336 udev->last_busy = jiffies;
1337 } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
1338 status = usb_suspend_both(udev, PMSG_SUSPEND);
1340 usb_pm_unlock(udev);
1344 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1345 void usb_autosuspend_work(struct work_struct *work)
1347 struct usb_device *udev =
1348 container_of(work, struct usb_device, autosuspend.work);
1350 usb_autopm_do_device(udev, 0);
1354 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1355 * @udev: the usb_device to autosuspend
1357 * This routine should be called when a core subsystem is finished using
1358 * @udev and wants to allow it to autosuspend. Examples would be when
1359 * @udev's device file in usbfs is closed or after a configuration change.
1361 * @udev's usage counter is decremented. If it or any of the usage counters
1362 * for an active interface is greater than 0, no autosuspend request will be
1363 * queued. (If an interface driver does not support autosuspend then its
1364 * usage counter is permanently positive.) Furthermore, if an interface
1365 * driver requires remote-wakeup capability during autosuspend but remote
1366 * wakeup is disabled, the autosuspend will fail.
1368 * Often the caller will hold @udev's device lock, but this is not
1371 * This routine can run only in process context.
1373 void usb_autosuspend_device(struct usb_device *udev)
1377 status = usb_autopm_do_device(udev, -1);
1378 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1379 __func__, udev->pm_usage_cnt);
1383 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1384 * @udev: the usb_device to autosuspend
1386 * This routine should be called when a core subsystem thinks @udev may
1387 * be ready to autosuspend.
1389 * @udev's usage counter left unchanged. If it or any of the usage counters
1390 * for an active interface is greater than 0, or autosuspend is not allowed
1391 * for any other reason, no autosuspend request will be queued.
1393 * This routine can run only in process context.
1395 void usb_try_autosuspend_device(struct usb_device *udev)
1397 usb_autopm_do_device(udev, 0);
1398 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1399 __func__, udev->pm_usage_cnt);
1403 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1404 * @udev: the usb_device to autoresume
1406 * This routine should be called when a core subsystem wants to use @udev
1407 * and needs to guarantee that it is not suspended. No autosuspend will
1408 * occur until usb_autosuspend_device is called. (Note that this will not
1409 * prevent suspend events originating in the PM core.) Examples would be
1410 * when @udev's device file in usbfs is opened or when a remote-wakeup
1411 * request is received.
1413 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1414 * However if the autoresume fails then the usage counter is re-decremented.
1416 * Often the caller will hold @udev's device lock, but this is not
1417 * necessary (and attempting it might cause deadlock).
1419 * This routine can run only in process context.
1421 int usb_autoresume_device(struct usb_device *udev)
1425 status = usb_autopm_do_device(udev, 1);
1426 dev_vdbg(&udev->dev, "%s: status %d cnt %d\n",
1427 __func__, status, udev->pm_usage_cnt);
1431 /* Internal routine to adjust an interface's usage counter and change
1432 * its device's autosuspend state.
1434 static int usb_autopm_do_interface(struct usb_interface *intf,
1437 struct usb_device *udev = interface_to_usbdev(intf);
1441 if (intf->condition == USB_INTERFACE_UNBOUND)
1445 intf->pm_usage_cnt += inc_usage_cnt;
1446 udev->last_busy = jiffies;
1447 if (inc_usage_cnt >= 0 && intf->pm_usage_cnt > 0) {
1448 if (udev->state == USB_STATE_SUSPENDED)
1449 status = usb_resume_both(udev);
1451 intf->pm_usage_cnt -= inc_usage_cnt;
1453 udev->last_busy = jiffies;
1454 } else if (inc_usage_cnt <= 0 && intf->pm_usage_cnt <= 0) {
1455 status = usb_suspend_both(udev, PMSG_SUSPEND);
1458 usb_pm_unlock(udev);
1463 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1464 * @intf: the usb_interface whose counter should be decremented
1466 * This routine should be called by an interface driver when it is
1467 * finished using @intf and wants to allow it to autosuspend. A typical
1468 * example would be a character-device driver when its device file is
1471 * The routine decrements @intf's usage counter. When the counter reaches
1472 * 0, a delayed autosuspend request for @intf's device is queued. When
1473 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1474 * the other usage counters for the sibling interfaces and @intf's
1475 * usb_device, the device and all its interfaces will be autosuspended.
1477 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1478 * core will not change its value other than the increment and decrement
1479 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1480 * may use this simple counter-oriented discipline or may set the value
1483 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1484 * take place only if the device's remote-wakeup facility is enabled.
1486 * Suspend method calls queued by this routine can arrive at any time
1487 * while @intf is resumed and its usage counter is equal to 0. They are
1488 * not protected by the usb_device's lock but only by its pm_mutex.
1489 * Drivers must provide their own synchronization.
1491 * This routine can run only in process context.
1493 void usb_autopm_put_interface(struct usb_interface *intf)
1497 status = usb_autopm_do_interface(intf, -1);
1498 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1499 __func__, status, intf->pm_usage_cnt);
1501 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1504 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1505 * @intf: the usb_interface whose counter should be incremented
1507 * This routine should be called by an interface driver when it wants to
1508 * use @intf and needs to guarantee that it is not suspended. In addition,
1509 * the routine prevents @intf from being autosuspended subsequently. (Note
1510 * that this will not prevent suspend events originating in the PM core.)
1511 * This prevention will persist until usb_autopm_put_interface() is called
1512 * or @intf is unbound. A typical example would be a character-device
1513 * driver when its device file is opened.
1516 * The routine increments @intf's usage counter. (However if the
1517 * autoresume fails then the counter is re-decremented.) So long as the
1518 * counter is greater than 0, autosuspend will not be allowed for @intf
1519 * or its usb_device. When the driver is finished using @intf it should
1520 * call usb_autopm_put_interface() to decrement the usage counter and
1521 * queue a delayed autosuspend request (if the counter is <= 0).
1524 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1525 * core will not change its value other than the increment and decrement
1526 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1527 * may use this simple counter-oriented discipline or may set the value
1530 * Resume method calls generated by this routine can arrive at any time
1531 * while @intf is suspended. They are not protected by the usb_device's
1532 * lock but only by its pm_mutex. Drivers must provide their own
1535 * This routine can run only in process context.
1537 int usb_autopm_get_interface(struct usb_interface *intf)
1541 status = usb_autopm_do_interface(intf, 1);
1542 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1543 __func__, status, intf->pm_usage_cnt);
1546 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1549 * usb_autopm_set_interface - set a USB interface's autosuspend state
1550 * @intf: the usb_interface whose state should be set
1552 * This routine sets the autosuspend state of @intf's device according
1553 * to @intf's usage counter, which the caller must have set previously.
1554 * If the counter is <= 0, the device is autosuspended (if it isn't
1555 * already suspended and if nothing else prevents the autosuspend). If
1556 * the counter is > 0, the device is autoresumed (if it isn't already
1559 int usb_autopm_set_interface(struct usb_interface *intf)
1563 status = usb_autopm_do_interface(intf, 0);
1564 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1565 __func__, status, intf->pm_usage_cnt);
1568 EXPORT_SYMBOL_GPL(usb_autopm_set_interface);
1572 void usb_autosuspend_work(struct work_struct *work)
1575 #endif /* CONFIG_USB_SUSPEND */
1578 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1579 * @udev: the usb_device to suspend
1580 * @msg: Power Management message describing this state transition
1582 * This routine handles external suspend requests: ones not generated
1583 * internally by a USB driver (autosuspend) but rather coming from the user
1584 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1585 * out regardless of @udev's usage counter or those of its interfaces,
1586 * and regardless of whether or not remote wakeup is enabled. Of course,
1587 * interface drivers still have the option of failing the suspend (if
1588 * there are unsuspended children, for example).
1590 * The caller must hold @udev's device lock.
1592 int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
1596 do_unbind_rebind(udev, DO_UNBIND);
1599 status = usb_suspend_both(udev, msg);
1600 usb_pm_unlock(udev);
1605 * usb_external_resume_device - external resume of a USB device and its interfaces
1606 * @udev: the usb_device to resume
1608 * This routine handles external resume requests: ones not generated
1609 * internally by a USB driver (autoresume) but rather coming from the user
1610 * (via sysfs), the PM core (system resume), or the device itself (remote
1611 * wakeup). @udev's usage counter is unaffected.
1613 * The caller must hold @udev's device lock.
1615 int usb_external_resume_device(struct usb_device *udev)
1621 status = usb_resume_both(udev);
1622 udev->last_busy = jiffies;
1623 usb_pm_unlock(udev);
1624 do_unbind_rebind(udev, DO_REBIND);
1626 /* Now that the device is awake, we can start trying to autosuspend
1629 usb_try_autosuspend_device(udev);
1633 static int usb_suspend(struct device *dev, pm_message_t message)
1635 struct usb_device *udev;
1637 if (!is_usb_device(dev)) /* Ignore PM for interfaces */
1639 udev = to_usb_device(dev);
1641 /* If udev is already suspended, we can skip this suspend and
1642 * we should also skip the upcoming system resume. High-speed
1643 * root hubs are an exception; they need to resume whenever the
1644 * system wakes up in order for USB-PERSIST port handover to work
1647 if (udev->state == USB_STATE_SUSPENDED) {
1648 if (udev->parent || udev->speed != USB_SPEED_HIGH)
1649 udev->skip_sys_resume = 1;
1653 udev->skip_sys_resume = 0;
1654 return usb_external_suspend_device(udev, message);
1657 static int usb_resume(struct device *dev)
1659 struct usb_device *udev;
1661 if (!is_usb_device(dev)) /* Ignore PM for interfaces */
1663 udev = to_usb_device(dev);
1665 /* If udev->skip_sys_resume is set then udev was already suspended
1666 * when the system sleep started, so we don't want to resume it
1667 * during this system wakeup.
1669 if (udev->skip_sys_resume)
1671 return usb_external_resume_device(udev);
1676 #define usb_suspend NULL
1677 #define usb_resume NULL
1679 #endif /* CONFIG_PM */
1681 struct bus_type usb_bus_type = {
1683 .match = usb_device_match,
1684 .uevent = usb_uevent,
1685 .suspend = usb_suspend,
1686 .resume = usb_resume,