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);
87 * store_remove_id - remove a USB device ID from this driver
88 * @driver: target device driver
89 * @buf: buffer for scanning device ID data
92 * Removes a dynamic usb device ID from this driver.
95 store_remove_id(struct device_driver *driver, const char *buf, size_t count)
97 struct usb_dynid *dynid, *n;
98 struct usb_driver *usb_driver = to_usb_driver(driver);
104 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
108 spin_lock(&usb_driver->dynids.lock);
109 list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) {
110 struct usb_device_id *id = &dynid->id;
111 if ((id->idVendor == idVendor) &&
112 (id->idProduct == idProduct)) {
113 list_del(&dynid->node);
119 spin_unlock(&usb_driver->dynids.lock);
125 static DRIVER_ATTR(remove_id, S_IWUSR, NULL, store_remove_id);
127 static int usb_create_newid_file(struct usb_driver *usb_drv)
131 if (usb_drv->no_dynamic_id)
134 if (usb_drv->probe != NULL)
135 error = driver_create_file(&usb_drv->drvwrap.driver,
136 &driver_attr_new_id);
141 static void usb_remove_newid_file(struct usb_driver *usb_drv)
143 if (usb_drv->no_dynamic_id)
146 if (usb_drv->probe != NULL)
147 driver_remove_file(&usb_drv->drvwrap.driver,
148 &driver_attr_new_id);
152 usb_create_removeid_file(struct usb_driver *drv)
155 if (drv->probe != NULL)
156 error = driver_create_file(&drv->drvwrap.driver,
157 &driver_attr_remove_id);
161 static void usb_remove_removeid_file(struct usb_driver *drv)
163 driver_remove_file(&drv->drvwrap.driver, &driver_attr_remove_id);
166 static void usb_free_dynids(struct usb_driver *usb_drv)
168 struct usb_dynid *dynid, *n;
170 spin_lock(&usb_drv->dynids.lock);
171 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
172 list_del(&dynid->node);
175 spin_unlock(&usb_drv->dynids.lock);
178 static inline int usb_create_newid_file(struct usb_driver *usb_drv)
183 static void usb_remove_newid_file(struct usb_driver *usb_drv)
188 usb_create_removeid_file(struct usb_driver *drv)
193 static void usb_remove_removeid_file(struct usb_driver *drv)
197 static inline void usb_free_dynids(struct usb_driver *usb_drv)
202 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
203 struct usb_driver *drv)
205 struct usb_dynid *dynid;
207 spin_lock(&drv->dynids.lock);
208 list_for_each_entry(dynid, &drv->dynids.list, node) {
209 if (usb_match_one_id(intf, &dynid->id)) {
210 spin_unlock(&drv->dynids.lock);
214 spin_unlock(&drv->dynids.lock);
219 /* called from driver core with dev locked */
220 static int usb_probe_device(struct device *dev)
222 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
223 struct usb_device *udev = to_usb_device(dev);
226 dev_dbg(dev, "%s\n", __func__);
228 /* TODO: Add real matching code */
230 /* The device should always appear to be in use
231 * unless the driver suports autosuspend.
233 udev->pm_usage_cnt = !(udriver->supports_autosuspend);
235 error = udriver->probe(udev);
239 /* called from driver core with dev locked */
240 static int usb_unbind_device(struct device *dev)
242 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
244 udriver->disconnect(to_usb_device(dev));
249 * Cancel any pending scheduled resets
251 * [see usb_queue_reset_device()]
253 * Called after unconfiguring / when releasing interfaces. See
254 * comments in __usb_queue_reset_device() regarding
255 * udev->reset_running.
257 static void usb_cancel_queued_reset(struct usb_interface *iface)
259 if (iface->reset_running == 0)
260 cancel_work_sync(&iface->reset_ws);
263 /* called from driver core with dev locked */
264 static int usb_probe_interface(struct device *dev)
266 struct usb_driver *driver = to_usb_driver(dev->driver);
267 struct usb_interface *intf = to_usb_interface(dev);
268 struct usb_device *udev = interface_to_usbdev(intf);
269 const struct usb_device_id *id;
272 dev_dbg(dev, "%s\n", __func__);
274 intf->needs_binding = 0;
276 if (usb_device_is_owned(udev))
279 if (udev->authorized == 0) {
280 dev_err(&intf->dev, "Device is not authorized for usage\n");
284 id = usb_match_id(intf, driver->id_table);
286 id = usb_match_dynamic_id(intf, driver);
288 dev_dbg(dev, "%s - got id\n", __func__);
290 error = usb_autoresume_device(udev);
294 /* Interface "power state" doesn't correspond to any hardware
295 * state whatsoever. We use it to record when it's bound to
296 * a driver that may start I/0: it's not frozen/quiesced.
299 intf->condition = USB_INTERFACE_BINDING;
301 /* The interface should always appear to be in use
302 * unless the driver suports autosuspend.
304 atomic_set(&intf->pm_usage_cnt, !driver->supports_autosuspend);
306 /* Carry out a deferred switch to altsetting 0 */
307 if (intf->needs_altsetting0) {
308 error = usb_set_interface(udev, intf->altsetting[0].
309 desc.bInterfaceNumber, 0);
313 intf->needs_altsetting0 = 0;
316 error = driver->probe(intf, id);
320 intf->condition = USB_INTERFACE_BOUND;
321 usb_autosuspend_device(udev);
328 intf->needs_remote_wakeup = 0;
329 intf->condition = USB_INTERFACE_UNBOUND;
330 usb_cancel_queued_reset(intf);
331 usb_autosuspend_device(udev);
335 /* called from driver core with dev locked */
336 static int usb_unbind_interface(struct device *dev)
338 struct usb_driver *driver = to_usb_driver(dev->driver);
339 struct usb_interface *intf = to_usb_interface(dev);
340 struct usb_device *udev;
343 intf->condition = USB_INTERFACE_UNBINDING;
345 /* Autoresume for set_interface call below */
346 udev = interface_to_usbdev(intf);
347 error = usb_autoresume_device(udev);
349 /* Terminate all URBs for this interface unless the driver
350 * supports "soft" unbinding.
352 if (!driver->soft_unbind)
353 usb_disable_interface(udev, intf, false);
355 driver->disconnect(intf);
356 usb_cancel_queued_reset(intf);
358 /* Reset other interface state.
359 * We cannot do a Set-Interface if the device is suspended or
360 * if it is prepared for a system sleep (since installing a new
361 * altsetting means creating new endpoint device entries).
362 * When either of these happens, defer the Set-Interface.
364 if (intf->cur_altsetting->desc.bAlternateSetting == 0) {
365 /* Already in altsetting 0 so skip Set-Interface.
366 * Just re-enable it without affecting the endpoint toggles.
368 usb_enable_interface(udev, intf, false);
369 } else if (!error && intf->dev.power.status == DPM_ON) {
370 r = usb_set_interface(udev, intf->altsetting[0].
371 desc.bInterfaceNumber, 0);
373 intf->needs_altsetting0 = 1;
375 intf->needs_altsetting0 = 1;
377 usb_set_intfdata(intf, NULL);
379 intf->condition = USB_INTERFACE_UNBOUND;
381 intf->needs_remote_wakeup = 0;
384 usb_autosuspend_device(udev);
390 * usb_driver_claim_interface - bind a driver to an interface
391 * @driver: the driver to be bound
392 * @iface: the interface to which it will be bound; must be in the
393 * usb device's active configuration
394 * @priv: driver data associated with that interface
396 * This is used by usb device drivers that need to claim more than one
397 * interface on a device when probing (audio and acm are current examples).
398 * No device driver should directly modify internal usb_interface or
399 * usb_device structure members.
401 * Few drivers should need to use this routine, since the most natural
402 * way to bind to an interface is to return the private data from
403 * the driver's probe() method.
405 * Callers must own the device lock, so driver probe() entries don't need
406 * extra locking, but other call contexts may need to explicitly claim that
409 int usb_driver_claim_interface(struct usb_driver *driver,
410 struct usb_interface *iface, void *priv)
412 struct device *dev = &iface->dev;
413 struct usb_device *udev = interface_to_usbdev(iface);
419 dev->driver = &driver->drvwrap.driver;
420 usb_set_intfdata(iface, priv);
421 iface->needs_binding = 0;
424 iface->condition = USB_INTERFACE_BOUND;
426 atomic_set(&iface->pm_usage_cnt, !driver->supports_autosuspend);
429 /* if interface was already added, bind now; else let
430 * the future device_add() bind it, bypassing probe()
432 if (device_is_registered(dev))
433 retval = device_bind_driver(dev);
437 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
440 * usb_driver_release_interface - unbind a driver from an interface
441 * @driver: the driver to be unbound
442 * @iface: the interface from which it will be unbound
444 * This can be used by drivers to release an interface without waiting
445 * for their disconnect() methods to be called. In typical cases this
446 * also causes the driver disconnect() method to be called.
448 * This call is synchronous, and may not be used in an interrupt context.
449 * Callers must own the device lock, so driver disconnect() entries don't
450 * need extra locking, but other call contexts may need to explicitly claim
453 void usb_driver_release_interface(struct usb_driver *driver,
454 struct usb_interface *iface)
456 struct device *dev = &iface->dev;
458 /* this should never happen, don't release something that's not ours */
459 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
462 /* don't release from within disconnect() */
463 if (iface->condition != USB_INTERFACE_BOUND)
465 iface->condition = USB_INTERFACE_UNBINDING;
467 /* Release via the driver core only if the interface
468 * has already been registered
470 if (device_is_registered(dev)) {
471 device_release_driver(dev);
474 usb_unbind_interface(dev);
479 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
481 /* returns 0 if no match, 1 if match */
482 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
484 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
485 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
488 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
489 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
492 /* No need to test id->bcdDevice_lo != 0, since 0 is never
493 greater than any unsigned number. */
494 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
495 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
498 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
499 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
502 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
503 (id->bDeviceClass != dev->descriptor.bDeviceClass))
506 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
507 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
510 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
511 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
517 /* returns 0 if no match, 1 if match */
518 int usb_match_one_id(struct usb_interface *interface,
519 const struct usb_device_id *id)
521 struct usb_host_interface *intf;
522 struct usb_device *dev;
524 /* proc_connectinfo in devio.c may call us with id == NULL. */
528 intf = interface->cur_altsetting;
529 dev = interface_to_usbdev(interface);
531 if (!usb_match_device(dev, id))
534 /* The interface class, subclass, and protocol should never be
535 * checked for a match if the device class is Vendor Specific,
536 * unless the match record specifies the Vendor ID. */
537 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
538 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
539 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
540 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
541 USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
544 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
545 (id->bInterfaceClass != intf->desc.bInterfaceClass))
548 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
549 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
552 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
553 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
558 EXPORT_SYMBOL_GPL(usb_match_one_id);
561 * usb_match_id - find first usb_device_id matching device or interface
562 * @interface: the interface of interest
563 * @id: array of usb_device_id structures, terminated by zero entry
565 * usb_match_id searches an array of usb_device_id's and returns
566 * the first one matching the device or interface, or null.
567 * This is used when binding (or rebinding) a driver to an interface.
568 * Most USB device drivers will use this indirectly, through the usb core,
569 * but some layered driver frameworks use it directly.
570 * These device tables are exported with MODULE_DEVICE_TABLE, through
571 * modutils, to support the driver loading functionality of USB hotplugging.
575 * The "match_flags" element in a usb_device_id controls which
576 * members are used. If the corresponding bit is set, the
577 * value in the device_id must match its corresponding member
578 * in the device or interface descriptor, or else the device_id
581 * "driver_info" is normally used only by device drivers,
582 * but you can create a wildcard "matches anything" usb_device_id
583 * as a driver's "modules.usbmap" entry if you provide an id with
584 * only a nonzero "driver_info" field. If you do this, the USB device
585 * driver's probe() routine should use additional intelligence to
586 * decide whether to bind to the specified interface.
588 * What Makes Good usb_device_id Tables:
590 * The match algorithm is very simple, so that intelligence in
591 * driver selection must come from smart driver id records.
592 * Unless you have good reasons to use another selection policy,
593 * provide match elements only in related groups, and order match
594 * specifiers from specific to general. Use the macros provided
595 * for that purpose if you can.
597 * The most specific match specifiers use device descriptor
598 * data. These are commonly used with product-specific matches;
599 * the USB_DEVICE macro lets you provide vendor and product IDs,
600 * and you can also match against ranges of product revisions.
601 * These are widely used for devices with application or vendor
602 * specific bDeviceClass values.
604 * Matches based on device class/subclass/protocol specifications
605 * are slightly more general; use the USB_DEVICE_INFO macro, or
606 * its siblings. These are used with single-function devices
607 * where bDeviceClass doesn't specify that each interface has
610 * Matches based on interface class/subclass/protocol are the
611 * most general; they let drivers bind to any interface on a
612 * multiple-function device. Use the USB_INTERFACE_INFO
613 * macro, or its siblings, to match class-per-interface style
614 * devices (as recorded in bInterfaceClass).
616 * Note that an entry created by USB_INTERFACE_INFO won't match
617 * any interface if the device class is set to Vendor-Specific.
618 * This is deliberate; according to the USB spec the meanings of
619 * the interface class/subclass/protocol for these devices are also
620 * vendor-specific, and hence matching against a standard product
621 * class wouldn't work anyway. If you really want to use an
622 * interface-based match for such a device, create a match record
623 * that also specifies the vendor ID. (Unforunately there isn't a
624 * standard macro for creating records like this.)
626 * Within those groups, remember that not all combinations are
627 * meaningful. For example, don't give a product version range
628 * without vendor and product IDs; or specify a protocol without
629 * its associated class and subclass.
631 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
632 const struct usb_device_id *id)
634 /* proc_connectinfo in devio.c may call us with id == NULL. */
638 /* It is important to check that id->driver_info is nonzero,
639 since an entry that is all zeroes except for a nonzero
640 id->driver_info is the way to create an entry that
641 indicates that the driver want to examine every
642 device and interface. */
643 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
644 id->bInterfaceClass || id->driver_info; id++) {
645 if (usb_match_one_id(interface, id))
651 EXPORT_SYMBOL_GPL(usb_match_id);
653 static int usb_device_match(struct device *dev, struct device_driver *drv)
655 /* devices and interfaces are handled separately */
656 if (is_usb_device(dev)) {
658 /* interface drivers never match devices */
659 if (!is_usb_device_driver(drv))
662 /* TODO: Add real matching code */
665 } else if (is_usb_interface(dev)) {
666 struct usb_interface *intf;
667 struct usb_driver *usb_drv;
668 const struct usb_device_id *id;
670 /* device drivers never match interfaces */
671 if (is_usb_device_driver(drv))
674 intf = to_usb_interface(dev);
675 usb_drv = to_usb_driver(drv);
677 id = usb_match_id(intf, usb_drv->id_table);
681 id = usb_match_dynamic_id(intf, usb_drv);
689 #ifdef CONFIG_HOTPLUG
690 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
692 struct usb_device *usb_dev;
694 /* driver is often null here; dev_dbg() would oops */
695 pr_debug("usb %s: uevent\n", dev_name(dev));
697 if (is_usb_device(dev)) {
698 usb_dev = to_usb_device(dev);
699 } else if (is_usb_interface(dev)) {
700 struct usb_interface *intf = to_usb_interface(dev);
702 usb_dev = interface_to_usbdev(intf);
707 if (usb_dev->devnum < 0) {
708 pr_debug("usb %s: already deleted?\n", dev_name(dev));
712 pr_debug("usb %s: bus removed?\n", dev_name(dev));
716 #ifdef CONFIG_USB_DEVICEFS
717 /* If this is available, userspace programs can directly read
718 * all the device descriptors we don't tell them about. Or
719 * act as usermode drivers.
721 if (add_uevent_var(env, "DEVICE=/proc/bus/usb/%03d/%03d",
722 usb_dev->bus->busnum, usb_dev->devnum))
726 /* per-device configurations are common */
727 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
728 le16_to_cpu(usb_dev->descriptor.idVendor),
729 le16_to_cpu(usb_dev->descriptor.idProduct),
730 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
733 /* class-based driver binding models */
734 if (add_uevent_var(env, "TYPE=%d/%d/%d",
735 usb_dev->descriptor.bDeviceClass,
736 usb_dev->descriptor.bDeviceSubClass,
737 usb_dev->descriptor.bDeviceProtocol))
745 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
749 #endif /* CONFIG_HOTPLUG */
752 * usb_register_device_driver - register a USB device (not interface) driver
753 * @new_udriver: USB operations for the device driver
754 * @owner: module owner of this driver.
756 * Registers a USB device driver with the USB core. The list of
757 * unattached devices will be rescanned whenever a new driver is
758 * added, allowing the new driver to attach to any recognized devices.
759 * Returns a negative error code on failure and 0 on success.
761 int usb_register_device_driver(struct usb_device_driver *new_udriver,
762 struct module *owner)
769 new_udriver->drvwrap.for_devices = 1;
770 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
771 new_udriver->drvwrap.driver.bus = &usb_bus_type;
772 new_udriver->drvwrap.driver.probe = usb_probe_device;
773 new_udriver->drvwrap.driver.remove = usb_unbind_device;
774 new_udriver->drvwrap.driver.owner = owner;
776 retval = driver_register(&new_udriver->drvwrap.driver);
779 pr_info("%s: registered new device driver %s\n",
780 usbcore_name, new_udriver->name);
781 usbfs_update_special();
783 printk(KERN_ERR "%s: error %d registering device "
785 usbcore_name, retval, new_udriver->name);
790 EXPORT_SYMBOL_GPL(usb_register_device_driver);
793 * usb_deregister_device_driver - unregister a USB device (not interface) driver
794 * @udriver: USB operations of the device driver to unregister
795 * Context: must be able to sleep
797 * Unlinks the specified driver from the internal USB driver list.
799 void usb_deregister_device_driver(struct usb_device_driver *udriver)
801 pr_info("%s: deregistering device driver %s\n",
802 usbcore_name, udriver->name);
804 driver_unregister(&udriver->drvwrap.driver);
805 usbfs_update_special();
807 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
810 * usb_register_driver - register a USB interface driver
811 * @new_driver: USB operations for the interface driver
812 * @owner: module owner of this driver.
813 * @mod_name: module name string
815 * Registers a USB interface driver with the USB core. The list of
816 * unattached interfaces will be rescanned whenever a new driver is
817 * added, allowing the new driver to attach to any recognized interfaces.
818 * Returns a negative error code on failure and 0 on success.
820 * NOTE: if you want your driver to use the USB major number, you must call
821 * usb_register_dev() to enable that functionality. This function no longer
822 * takes care of that.
824 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
825 const char *mod_name)
832 new_driver->drvwrap.for_devices = 0;
833 new_driver->drvwrap.driver.name = (char *) new_driver->name;
834 new_driver->drvwrap.driver.bus = &usb_bus_type;
835 new_driver->drvwrap.driver.probe = usb_probe_interface;
836 new_driver->drvwrap.driver.remove = usb_unbind_interface;
837 new_driver->drvwrap.driver.owner = owner;
838 new_driver->drvwrap.driver.mod_name = mod_name;
839 spin_lock_init(&new_driver->dynids.lock);
840 INIT_LIST_HEAD(&new_driver->dynids.list);
842 retval = driver_register(&new_driver->drvwrap.driver);
846 usbfs_update_special();
848 retval = usb_create_newid_file(new_driver);
852 retval = usb_create_removeid_file(new_driver);
856 pr_info("%s: registered new interface driver %s\n",
857 usbcore_name, new_driver->name);
863 usb_remove_newid_file(new_driver);
865 driver_unregister(&new_driver->drvwrap.driver);
867 printk(KERN_ERR "%s: error %d registering interface "
869 usbcore_name, retval, new_driver->name);
872 EXPORT_SYMBOL_GPL(usb_register_driver);
875 * usb_deregister - unregister a USB interface driver
876 * @driver: USB operations of the interface driver to unregister
877 * Context: must be able to sleep
879 * Unlinks the specified driver from the internal USB driver list.
881 * NOTE: If you called usb_register_dev(), you still need to call
882 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
883 * this * call will no longer do it for you.
885 void usb_deregister(struct usb_driver *driver)
887 pr_info("%s: deregistering interface driver %s\n",
888 usbcore_name, driver->name);
890 usb_remove_removeid_file(driver);
891 usb_remove_newid_file(driver);
892 usb_free_dynids(driver);
893 driver_unregister(&driver->drvwrap.driver);
895 usbfs_update_special();
897 EXPORT_SYMBOL_GPL(usb_deregister);
899 /* Forced unbinding of a USB interface driver, either because
900 * it doesn't support pre_reset/post_reset/reset_resume or
901 * because it doesn't support suspend/resume.
903 * The caller must hold @intf's device's lock, but not its pm_mutex
904 * and not @intf->dev.sem.
906 void usb_forced_unbind_intf(struct usb_interface *intf)
908 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
910 dev_dbg(&intf->dev, "forced unbind\n");
911 usb_driver_release_interface(driver, intf);
913 /* Mark the interface for later rebinding */
914 intf->needs_binding = 1;
917 /* Delayed forced unbinding of a USB interface driver and scan
920 * The caller must hold @intf's device's lock, but not its pm_mutex
921 * and not @intf->dev.sem.
923 * Note: Rebinds will be skipped if a system sleep transition is in
924 * progress and the PM "complete" callback hasn't occurred yet.
926 void usb_rebind_intf(struct usb_interface *intf)
930 /* Delayed unbind of an existing driver */
931 if (intf->dev.driver) {
932 struct usb_driver *driver =
933 to_usb_driver(intf->dev.driver);
935 dev_dbg(&intf->dev, "forced unbind\n");
936 usb_driver_release_interface(driver, intf);
939 /* Try to rebind the interface */
940 if (intf->dev.power.status == DPM_ON) {
941 intf->needs_binding = 0;
942 rc = device_attach(&intf->dev);
944 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
953 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
954 * or rebind interfaces that have been unbound, according to @action.
956 * The caller must hold @udev's device lock.
958 static void do_unbind_rebind(struct usb_device *udev, int action)
960 struct usb_host_config *config;
962 struct usb_interface *intf;
963 struct usb_driver *drv;
965 config = udev->actconfig;
967 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
968 intf = config->interface[i];
971 if (intf->dev.driver) {
972 drv = to_usb_driver(intf->dev.driver);
973 if (!drv->suspend || !drv->resume)
974 usb_forced_unbind_intf(intf);
978 if (intf->needs_binding)
979 usb_rebind_intf(intf);
986 /* Caller has locked udev's pm_mutex */
987 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
989 struct usb_device_driver *udriver;
992 if (udev->state == USB_STATE_NOTATTACHED ||
993 udev->state == USB_STATE_SUSPENDED)
996 /* For devices that don't have a driver, we do a generic suspend. */
997 if (udev->dev.driver)
998 udriver = to_usb_device_driver(udev->dev.driver);
1000 udev->do_remote_wakeup = 0;
1001 udriver = &usb_generic_driver;
1003 status = udriver->suspend(udev, msg);
1006 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1010 /* Caller has locked udev's pm_mutex */
1011 static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1013 struct usb_device_driver *udriver;
1016 if (udev->state == USB_STATE_NOTATTACHED)
1019 /* Can't resume it if it doesn't have a driver. */
1020 if (udev->dev.driver == NULL) {
1025 /* Non-root devices on a full/low-speed bus must wait for their
1026 * companion high-speed root hub, in case a handoff is needed.
1028 if (!(msg.event & PM_EVENT_AUTO) && udev->parent &&
1029 udev->bus->hs_companion)
1030 device_pm_wait_for_dev(&udev->dev,
1031 &udev->bus->hs_companion->root_hub->dev);
1033 if (udev->quirks & USB_QUIRK_RESET_RESUME)
1034 udev->reset_resume = 1;
1036 udriver = to_usb_device_driver(udev->dev.driver);
1037 status = udriver->resume(udev, msg);
1040 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1044 /* Caller has locked intf's usb_device's pm mutex */
1045 static int usb_suspend_interface(struct usb_device *udev,
1046 struct usb_interface *intf, pm_message_t msg)
1048 struct usb_driver *driver;
1051 /* with no hardware, USB interfaces only use FREEZE and ON states */
1052 if (udev->state == USB_STATE_NOTATTACHED || !is_active(intf))
1055 /* This can happen; see usb_driver_release_interface() */
1056 if (intf->condition == USB_INTERFACE_UNBOUND)
1058 driver = to_usb_driver(intf->dev.driver);
1060 if (driver->suspend) {
1061 status = driver->suspend(intf, msg);
1063 mark_quiesced(intf);
1064 else if (!(msg.event & PM_EVENT_AUTO))
1065 dev_err(&intf->dev, "%s error %d\n",
1068 /* Later we will unbind the driver and reprobe */
1069 intf->needs_binding = 1;
1070 dev_warn(&intf->dev, "no %s for driver %s?\n",
1071 "suspend", driver->name);
1072 mark_quiesced(intf);
1076 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1080 /* Caller has locked intf's usb_device's pm_mutex */
1081 static int usb_resume_interface(struct usb_device *udev,
1082 struct usb_interface *intf, pm_message_t msg, int reset_resume)
1084 struct usb_driver *driver;
1087 if (udev->state == USB_STATE_NOTATTACHED || is_active(intf))
1090 /* Don't let autoresume interfere with unbinding */
1091 if (intf->condition == USB_INTERFACE_UNBINDING)
1094 /* Can't resume it if it doesn't have a driver. */
1095 if (intf->condition == USB_INTERFACE_UNBOUND) {
1097 /* Carry out a deferred switch to altsetting 0 */
1098 if (intf->needs_altsetting0 &&
1099 intf->dev.power.status == DPM_ON) {
1100 usb_set_interface(udev, intf->altsetting[0].
1101 desc.bInterfaceNumber, 0);
1102 intf->needs_altsetting0 = 0;
1107 /* Don't resume if the interface is marked for rebinding */
1108 if (intf->needs_binding)
1110 driver = to_usb_driver(intf->dev.driver);
1113 if (driver->reset_resume) {
1114 status = driver->reset_resume(intf);
1116 dev_err(&intf->dev, "%s error %d\n",
1117 "reset_resume", status);
1119 intf->needs_binding = 1;
1120 dev_warn(&intf->dev, "no %s for driver %s?\n",
1121 "reset_resume", driver->name);
1124 if (driver->resume) {
1125 status = driver->resume(intf);
1127 dev_err(&intf->dev, "%s error %d\n",
1130 intf->needs_binding = 1;
1131 dev_warn(&intf->dev, "no %s for driver %s?\n",
1132 "resume", driver->name);
1137 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1138 if (status == 0 && intf->condition == USB_INTERFACE_BOUND)
1141 /* Later we will unbind the driver and/or reprobe, if necessary */
1145 #ifdef CONFIG_USB_SUSPEND
1147 /* Internal routine to check whether we may autosuspend a device. */
1148 static int autosuspend_check(struct usb_device *udev, int reschedule)
1151 struct usb_interface *intf;
1152 unsigned long suspend_time, j;
1154 /* For autosuspend, fail fast if anything is in use or autosuspend
1155 * is disabled. Also fail if any interfaces require remote wakeup
1156 * but it isn't available.
1158 if (udev->pm_usage_cnt > 0)
1160 if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
1163 suspend_time = udev->last_busy + udev->autosuspend_delay;
1164 if (udev->actconfig) {
1165 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1166 intf = udev->actconfig->interface[i];
1167 if (!is_active(intf))
1169 if (atomic_read(&intf->pm_usage_cnt) > 0)
1171 if (intf->needs_remote_wakeup &&
1172 !udev->do_remote_wakeup) {
1173 dev_dbg(&udev->dev, "remote wakeup needed "
1174 "for autosuspend\n");
1178 /* Don't allow autosuspend if the device will need
1179 * a reset-resume and any of its interface drivers
1180 * doesn't include support.
1182 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1183 struct usb_driver *driver;
1185 driver = to_usb_driver(intf->dev.driver);
1186 if (!driver->reset_resume ||
1187 intf->needs_remote_wakeup)
1193 /* If everything is okay but the device hasn't been idle for long
1194 * enough, queue a delayed autosuspend request. If the device
1195 * _has_ been idle for long enough and the reschedule flag is set,
1196 * likewise queue a delayed (1 second) autosuspend request.
1199 if (time_before(j, suspend_time))
1202 suspend_time = j + HZ;
1204 if (!timer_pending(&udev->autosuspend.timer)) {
1205 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
1206 round_jiffies_up_relative(suspend_time - j));
1215 static inline int autosuspend_check(struct usb_device *udev, int reschedule)
1220 #endif /* CONFIG_USB_SUSPEND */
1223 * usb_suspend_both - suspend a USB device and its interfaces
1224 * @udev: the usb_device to suspend
1225 * @msg: Power Management message describing this state transition
1227 * This is the central routine for suspending USB devices. It calls the
1228 * suspend methods for all the interface drivers in @udev and then calls
1229 * the suspend method for @udev itself. If an error occurs at any stage,
1230 * all the interfaces which were suspended are resumed so that they remain
1231 * in the same state as the device.
1233 * If an autosuspend is in progress the routine checks first to make sure
1234 * that neither the device itself or any of its active interfaces is in use
1235 * (pm_usage_cnt is greater than 0). If they are, the autosuspend fails.
1237 * If the suspend succeeds, the routine recursively queues an autosuspend
1238 * request for @udev's parent device, thereby propagating the change up
1239 * the device tree. If all of the parent's children are now suspended,
1240 * the parent will autosuspend in turn.
1242 * The suspend method calls are subject to mutual exclusion under control
1243 * of @udev's pm_mutex. Many of these calls are also under the protection
1244 * of @udev's device lock (including all requests originating outside the
1245 * USB subsystem), but autosuspend requests generated by a child device or
1246 * interface driver may not be. Usbcore will insure that the method calls
1247 * do not arrive during bind, unbind, or reset operations. However, drivers
1248 * must be prepared to handle suspend calls arriving at unpredictable times.
1249 * The only way to block such calls is to do an autoresume (preventing
1250 * autosuspends) while holding @udev's device lock (preventing outside
1253 * The caller must hold @udev->pm_mutex.
1255 * This routine can run only in process context.
1257 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1261 struct usb_interface *intf;
1262 struct usb_device *parent = udev->parent;
1264 if (udev->state == USB_STATE_NOTATTACHED ||
1265 udev->state == USB_STATE_SUSPENDED)
1268 udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
1270 if (msg.event & PM_EVENT_AUTO) {
1271 status = autosuspend_check(udev, 0);
1276 /* Suspend all the interfaces and then udev itself */
1277 if (udev->actconfig) {
1278 for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
1279 intf = udev->actconfig->interface[i];
1280 status = usb_suspend_interface(udev, intf, msg);
1286 status = usb_suspend_device(udev, msg);
1288 /* If the suspend failed, resume interfaces that did get suspended */
1292 msg2.event = msg.event ^ (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1294 intf = udev->actconfig->interface[i];
1295 usb_resume_interface(udev, intf, msg2, 0);
1298 /* Try another autosuspend when the interfaces aren't busy */
1299 if (msg.event & PM_EVENT_AUTO)
1300 autosuspend_check(udev, status == -EBUSY);
1302 /* If the suspend succeeded then prevent any more URB submissions,
1303 * flush any outstanding URBs, and propagate the suspend up the tree.
1306 cancel_delayed_work(&udev->autosuspend);
1307 udev->can_submit = 0;
1308 for (i = 0; i < 16; ++i) {
1309 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1310 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1313 /* If this is just a FREEZE or a PRETHAW, udev might
1314 * not really be suspended. Only true suspends get
1315 * propagated up the device tree.
1317 if (parent && udev->state == USB_STATE_SUSPENDED)
1318 usb_autosuspend_device(parent);
1322 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1327 * usb_resume_both - resume a USB device and its interfaces
1328 * @udev: the usb_device to resume
1329 * @msg: Power Management message describing this state transition
1331 * This is the central routine for resuming USB devices. It calls the
1332 * the resume method for @udev and then calls the resume methods for all
1333 * the interface drivers in @udev.
1335 * Before starting the resume, the routine calls itself recursively for
1336 * the parent device of @udev, thereby propagating the change up the device
1337 * tree and assuring that @udev will be able to resume. If the parent is
1338 * unable to resume successfully, the routine fails.
1340 * The resume method calls are subject to mutual exclusion under control
1341 * of @udev's pm_mutex. Many of these calls are also under the protection
1342 * of @udev's device lock (including all requests originating outside the
1343 * USB subsystem), but autoresume requests generated by a child device or
1344 * interface driver may not be. Usbcore will insure that the method calls
1345 * do not arrive during bind, unbind, or reset operations. However, drivers
1346 * must be prepared to handle resume calls arriving at unpredictable times.
1347 * The only way to block such calls is to do an autoresume (preventing
1348 * other autoresumes) while holding @udev's device lock (preventing outside
1351 * The caller must hold @udev->pm_mutex.
1353 * This routine can run only in process context.
1355 static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1359 struct usb_interface *intf;
1360 struct usb_device *parent = udev->parent;
1362 cancel_delayed_work(&udev->autosuspend);
1363 if (udev->state == USB_STATE_NOTATTACHED) {
1367 udev->can_submit = 1;
1369 /* Propagate the resume up the tree, if necessary */
1370 if (udev->state == USB_STATE_SUSPENDED) {
1372 status = usb_autoresume_device(parent);
1374 status = usb_resume_device(udev, msg);
1375 if (status || udev->state ==
1376 USB_STATE_NOTATTACHED) {
1377 usb_autosuspend_device(parent);
1379 /* It's possible usb_resume_device()
1380 * failed after the port was
1381 * unsuspended, causing udev to be
1382 * logically disconnected. We don't
1383 * want usb_disconnect() to autosuspend
1384 * the parent again, so tell it that
1385 * udev disconnected while still
1388 USB_STATE_NOTATTACHED)
1389 udev->discon_suspended = 1;
1394 /* We can't progagate beyond the USB subsystem,
1395 * so if a root hub's controller is suspended
1396 * then we're stuck. */
1397 status = usb_resume_device(udev, msg);
1399 } else if (udev->reset_resume)
1400 status = usb_resume_device(udev, msg);
1402 if (status == 0 && udev->actconfig) {
1403 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1404 intf = udev->actconfig->interface[i];
1405 usb_resume_interface(udev, intf, msg,
1406 udev->reset_resume);
1411 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1413 udev->reset_resume = 0;
1417 #ifdef CONFIG_USB_SUSPEND
1419 /* Internal routine to adjust a device's usage counter and change
1420 * its autosuspend state.
1422 static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
1427 udev->pm_usage_cnt += inc_usage_cnt;
1428 WARN_ON(udev->pm_usage_cnt < 0);
1430 udev->last_busy = jiffies;
1431 if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
1432 if (udev->state == USB_STATE_SUSPENDED)
1433 status = usb_resume_both(udev, PMSG_AUTO_RESUME);
1435 udev->pm_usage_cnt -= inc_usage_cnt;
1436 else if (inc_usage_cnt)
1437 udev->last_busy = jiffies;
1438 } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
1439 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1441 usb_pm_unlock(udev);
1445 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1446 void usb_autosuspend_work(struct work_struct *work)
1448 struct usb_device *udev =
1449 container_of(work, struct usb_device, autosuspend.work);
1451 usb_autopm_do_device(udev, 0);
1454 /* usb_autoresume_work - callback routine to autoresume a USB device */
1455 void usb_autoresume_work(struct work_struct *work)
1457 struct usb_device *udev =
1458 container_of(work, struct usb_device, autoresume);
1460 /* Wake it up, let the drivers do their thing, and then put it
1463 if (usb_autopm_do_device(udev, 1) == 0)
1464 usb_autopm_do_device(udev, -1);
1468 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1469 * @udev: the usb_device to autosuspend
1471 * This routine should be called when a core subsystem is finished using
1472 * @udev and wants to allow it to autosuspend. Examples would be when
1473 * @udev's device file in usbfs is closed or after a configuration change.
1475 * @udev's usage counter is decremented. If it or any of the usage counters
1476 * for an active interface is greater than 0, no autosuspend request will be
1477 * queued. (If an interface driver does not support autosuspend then its
1478 * usage counter is permanently positive.) Furthermore, if an interface
1479 * driver requires remote-wakeup capability during autosuspend but remote
1480 * wakeup is disabled, the autosuspend will fail.
1482 * Often the caller will hold @udev's device lock, but this is not
1485 * This routine can run only in process context.
1487 void usb_autosuspend_device(struct usb_device *udev)
1491 status = usb_autopm_do_device(udev, -1);
1492 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1493 __func__, udev->pm_usage_cnt);
1497 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1498 * @udev: the usb_device to autosuspend
1500 * This routine should be called when a core subsystem thinks @udev may
1501 * be ready to autosuspend.
1503 * @udev's usage counter left unchanged. If it or any of the usage counters
1504 * for an active interface is greater than 0, or autosuspend is not allowed
1505 * for any other reason, no autosuspend request will be queued.
1507 * This routine can run only in process context.
1509 void usb_try_autosuspend_device(struct usb_device *udev)
1511 usb_autopm_do_device(udev, 0);
1512 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1513 __func__, udev->pm_usage_cnt);
1517 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1518 * @udev: the usb_device to autoresume
1520 * This routine should be called when a core subsystem wants to use @udev
1521 * and needs to guarantee that it is not suspended. No autosuspend will
1522 * occur until usb_autosuspend_device is called. (Note that this will not
1523 * prevent suspend events originating in the PM core.) Examples would be
1524 * when @udev's device file in usbfs is opened or when a remote-wakeup
1525 * request is received.
1527 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1528 * However if the autoresume fails then the usage counter is re-decremented.
1530 * Often the caller will hold @udev's device lock, but this is not
1531 * necessary (and attempting it might cause deadlock).
1533 * This routine can run only in process context.
1535 int usb_autoresume_device(struct usb_device *udev)
1539 status = usb_autopm_do_device(udev, 1);
1540 dev_vdbg(&udev->dev, "%s: status %d cnt %d\n",
1541 __func__, status, udev->pm_usage_cnt);
1545 /* Internal routine to adjust an interface's usage counter and change
1546 * its device's autosuspend state.
1548 static int usb_autopm_do_interface(struct usb_interface *intf,
1551 struct usb_device *udev = interface_to_usbdev(intf);
1555 if (intf->condition == USB_INTERFACE_UNBOUND)
1558 atomic_add(inc_usage_cnt, &intf->pm_usage_cnt);
1559 udev->last_busy = jiffies;
1560 if (inc_usage_cnt >= 0 &&
1561 atomic_read(&intf->pm_usage_cnt) > 0) {
1562 if (udev->state == USB_STATE_SUSPENDED)
1563 status = usb_resume_both(udev,
1566 atomic_sub(inc_usage_cnt, &intf->pm_usage_cnt);
1568 udev->last_busy = jiffies;
1569 } else if (inc_usage_cnt <= 0 &&
1570 atomic_read(&intf->pm_usage_cnt) <= 0) {
1571 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1574 usb_pm_unlock(udev);
1579 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1580 * @intf: the usb_interface whose counter should be decremented
1582 * This routine should be called by an interface driver when it is
1583 * finished using @intf and wants to allow it to autosuspend. A typical
1584 * example would be a character-device driver when its device file is
1587 * The routine decrements @intf's usage counter. When the counter reaches
1588 * 0, a delayed autosuspend request for @intf's device is queued. When
1589 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1590 * the other usage counters for the sibling interfaces and @intf's
1591 * usb_device, the device and all its interfaces will be autosuspended.
1593 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1594 * core will not change its value other than the increment and decrement
1595 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1596 * may use this simple counter-oriented discipline or may set the value
1599 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1600 * take place only if the device's remote-wakeup facility is enabled.
1602 * Suspend method calls queued by this routine can arrive at any time
1603 * while @intf is resumed and its usage counter is equal to 0. They are
1604 * not protected by the usb_device's lock but only by its pm_mutex.
1605 * Drivers must provide their own synchronization.
1607 * This routine can run only in process context.
1609 void usb_autopm_put_interface(struct usb_interface *intf)
1613 status = usb_autopm_do_interface(intf, -1);
1614 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1615 __func__, status, atomic_read(&intf->pm_usage_cnt));
1617 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1620 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1621 * @intf: the usb_interface whose counter should be decremented
1623 * This routine does essentially the same thing as
1624 * usb_autopm_put_interface(): it decrements @intf's usage counter and
1625 * queues a delayed autosuspend request if the counter is <= 0. The
1626 * difference is that it does not acquire the device's pm_mutex;
1627 * callers must handle all synchronization issues themselves.
1629 * Typically a driver would call this routine during an URB's completion
1630 * handler, if no more URBs were pending.
1632 * This routine can run in atomic context.
1634 void usb_autopm_put_interface_async(struct usb_interface *intf)
1636 struct usb_device *udev = interface_to_usbdev(intf);
1639 if (intf->condition == USB_INTERFACE_UNBOUND) {
1642 udev->last_busy = jiffies;
1643 atomic_dec(&intf->pm_usage_cnt);
1644 if (udev->autosuspend_disabled || udev->autosuspend_delay < 0)
1646 else if (atomic_read(&intf->pm_usage_cnt) <= 0 &&
1647 !timer_pending(&udev->autosuspend.timer)) {
1648 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
1649 round_jiffies_up_relative(
1650 udev->autosuspend_delay));
1653 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1654 __func__, status, atomic_read(&intf->pm_usage_cnt));
1656 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1659 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1660 * @intf: the usb_interface whose counter should be incremented
1662 * This routine should be called by an interface driver when it wants to
1663 * use @intf and needs to guarantee that it is not suspended. In addition,
1664 * the routine prevents @intf from being autosuspended subsequently. (Note
1665 * that this will not prevent suspend events originating in the PM core.)
1666 * This prevention will persist until usb_autopm_put_interface() is called
1667 * or @intf is unbound. A typical example would be a character-device
1668 * driver when its device file is opened.
1671 * The routine increments @intf's usage counter. (However if the
1672 * autoresume fails then the counter is re-decremented.) So long as the
1673 * counter is greater than 0, autosuspend will not be allowed for @intf
1674 * or its usb_device. When the driver is finished using @intf it should
1675 * call usb_autopm_put_interface() to decrement the usage counter and
1676 * queue a delayed autosuspend request (if the counter is <= 0).
1679 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1680 * core will not change its value other than the increment and decrement
1681 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1682 * may use this simple counter-oriented discipline or may set the value
1685 * Resume method calls generated by this routine can arrive at any time
1686 * while @intf is suspended. They are not protected by the usb_device's
1687 * lock but only by its pm_mutex. Drivers must provide their own
1690 * This routine can run only in process context.
1692 int usb_autopm_get_interface(struct usb_interface *intf)
1696 status = usb_autopm_do_interface(intf, 1);
1697 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1698 __func__, status, atomic_read(&intf->pm_usage_cnt));
1701 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1704 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1705 * @intf: the usb_interface whose counter should be incremented
1707 * This routine does much the same thing as
1708 * usb_autopm_get_interface(): it increments @intf's usage counter and
1709 * queues an autoresume request if the result is > 0. The differences
1710 * are that it does not acquire the device's pm_mutex (callers must
1711 * handle all synchronization issues themselves), and it does not
1712 * autoresume the device directly (it only queues a request). After a
1713 * successful call, the device will generally not yet be resumed.
1715 * This routine can run in atomic context.
1717 int usb_autopm_get_interface_async(struct usb_interface *intf)
1719 struct usb_device *udev = interface_to_usbdev(intf);
1722 if (intf->condition == USB_INTERFACE_UNBOUND)
1725 atomic_inc(&intf->pm_usage_cnt);
1726 if (atomic_read(&intf->pm_usage_cnt) > 0 &&
1727 udev->state == USB_STATE_SUSPENDED)
1728 queue_work(ksuspend_usb_wq, &udev->autoresume);
1730 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1731 __func__, status, atomic_read(&intf->pm_usage_cnt));
1734 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1738 void usb_autosuspend_work(struct work_struct *work)
1741 void usb_autoresume_work(struct work_struct *work)
1744 #endif /* CONFIG_USB_SUSPEND */
1747 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1748 * @udev: the usb_device to suspend
1749 * @msg: Power Management message describing this state transition
1751 * This routine handles external suspend requests: ones not generated
1752 * internally by a USB driver (autosuspend) but rather coming from the user
1753 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1754 * out regardless of @udev's usage counter or those of its interfaces,
1755 * and regardless of whether or not remote wakeup is enabled. Of course,
1756 * interface drivers still have the option of failing the suspend (if
1757 * there are unsuspended children, for example).
1759 * The caller must hold @udev's device lock.
1761 int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
1765 do_unbind_rebind(udev, DO_UNBIND);
1767 status = usb_suspend_both(udev, msg);
1768 usb_pm_unlock(udev);
1773 * usb_external_resume_device - external resume of a USB device and its interfaces
1774 * @udev: the usb_device to resume
1775 * @msg: Power Management message describing this state transition
1777 * This routine handles external resume requests: ones not generated
1778 * internally by a USB driver (autoresume) but rather coming from the user
1779 * (via sysfs), the PM core (system resume), or the device itself (remote
1780 * wakeup). @udev's usage counter is unaffected.
1782 * The caller must hold @udev's device lock.
1784 int usb_external_resume_device(struct usb_device *udev, pm_message_t msg)
1789 status = usb_resume_both(udev, msg);
1790 udev->last_busy = jiffies;
1791 usb_pm_unlock(udev);
1793 do_unbind_rebind(udev, DO_REBIND);
1795 /* Now that the device is awake, we can start trying to autosuspend
1798 usb_try_autosuspend_device(udev);
1802 int usb_suspend(struct device *dev, pm_message_t msg)
1804 struct usb_device *udev;
1806 udev = to_usb_device(dev);
1808 /* If udev is already suspended, we can skip this suspend and
1809 * we should also skip the upcoming system resume. High-speed
1810 * root hubs are an exception; they need to resume whenever the
1811 * system wakes up in order for USB-PERSIST port handover to work
1814 if (udev->state == USB_STATE_SUSPENDED) {
1815 if (udev->parent || udev->speed != USB_SPEED_HIGH)
1816 udev->skip_sys_resume = 1;
1820 udev->skip_sys_resume = 0;
1821 return usb_external_suspend_device(udev, msg);
1824 int usb_resume(struct device *dev, pm_message_t msg)
1826 struct usb_device *udev;
1829 udev = to_usb_device(dev);
1831 /* If udev->skip_sys_resume is set then udev was already suspended
1832 * when the system sleep started, so we don't want to resume it
1833 * during this system wakeup.
1835 if (udev->skip_sys_resume)
1837 status = usb_external_resume_device(udev, msg);
1839 /* Avoid PM error messages for devices disconnected while suspended
1840 * as we'll display regular disconnect messages just a bit later.
1842 if (status == -ENODEV)
1847 #endif /* CONFIG_PM */
1849 struct bus_type usb_bus_type = {
1851 .match = usb_device_match,
1852 .uevent = usb_uevent,