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/slab.h>
27 #include <linux/export.h>
28 #include <linux/usb.h>
29 #include <linux/usb/quirks.h>
30 #include <linux/usb/hcd.h>
38 * Adds a new dynamic USBdevice ID to this driver,
39 * and cause the driver to probe for all devices again.
41 ssize_t usb_store_new_id(struct usb_dynids *dynids,
42 struct device_driver *driver,
43 const char *buf, size_t count)
45 struct usb_dynid *dynid;
51 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
55 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
59 INIT_LIST_HEAD(&dynid->node);
60 dynid->id.idVendor = idVendor;
61 dynid->id.idProduct = idProduct;
62 dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
64 spin_lock(&dynids->lock);
65 list_add_tail(&dynid->node, &dynids->list);
66 spin_unlock(&dynids->lock);
68 if (get_driver(driver)) {
69 retval = driver_attach(driver);
77 EXPORT_SYMBOL_GPL(usb_store_new_id);
79 static ssize_t store_new_id(struct device_driver *driver,
80 const char *buf, size_t count)
82 struct usb_driver *usb_drv = to_usb_driver(driver);
84 return usb_store_new_id(&usb_drv->dynids, driver, buf, count);
86 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
89 * store_remove_id - remove a USB device ID from this driver
90 * @driver: target device driver
91 * @buf: buffer for scanning device ID data
94 * Removes a dynamic usb device ID from this driver.
97 store_remove_id(struct device_driver *driver, const char *buf, size_t count)
99 struct usb_dynid *dynid, *n;
100 struct usb_driver *usb_driver = to_usb_driver(driver);
106 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
110 spin_lock(&usb_driver->dynids.lock);
111 list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) {
112 struct usb_device_id *id = &dynid->id;
113 if ((id->idVendor == idVendor) &&
114 (id->idProduct == idProduct)) {
115 list_del(&dynid->node);
121 spin_unlock(&usb_driver->dynids.lock);
127 static DRIVER_ATTR(remove_id, S_IWUSR, NULL, store_remove_id);
129 static int usb_create_newid_file(struct usb_driver *usb_drv)
133 if (usb_drv->no_dynamic_id)
136 if (usb_drv->probe != NULL)
137 error = driver_create_file(&usb_drv->drvwrap.driver,
138 &driver_attr_new_id);
143 static void usb_remove_newid_file(struct usb_driver *usb_drv)
145 if (usb_drv->no_dynamic_id)
148 if (usb_drv->probe != NULL)
149 driver_remove_file(&usb_drv->drvwrap.driver,
150 &driver_attr_new_id);
154 usb_create_removeid_file(struct usb_driver *drv)
157 if (drv->probe != NULL)
158 error = driver_create_file(&drv->drvwrap.driver,
159 &driver_attr_remove_id);
163 static void usb_remove_removeid_file(struct usb_driver *drv)
165 driver_remove_file(&drv->drvwrap.driver, &driver_attr_remove_id);
168 static void usb_free_dynids(struct usb_driver *usb_drv)
170 struct usb_dynid *dynid, *n;
172 spin_lock(&usb_drv->dynids.lock);
173 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
174 list_del(&dynid->node);
177 spin_unlock(&usb_drv->dynids.lock);
180 static inline int usb_create_newid_file(struct usb_driver *usb_drv)
185 static void usb_remove_newid_file(struct usb_driver *usb_drv)
190 usb_create_removeid_file(struct usb_driver *drv)
195 static void usb_remove_removeid_file(struct usb_driver *drv)
199 static inline void usb_free_dynids(struct usb_driver *usb_drv)
204 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
205 struct usb_driver *drv)
207 struct usb_dynid *dynid;
209 spin_lock(&drv->dynids.lock);
210 list_for_each_entry(dynid, &drv->dynids.list, node) {
211 if (usb_match_one_id(intf, &dynid->id)) {
212 spin_unlock(&drv->dynids.lock);
216 spin_unlock(&drv->dynids.lock);
221 /* called from driver core with dev locked */
222 static int usb_probe_device(struct device *dev)
224 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
225 struct usb_device *udev = to_usb_device(dev);
228 dev_dbg(dev, "%s\n", __func__);
230 /* TODO: Add real matching code */
232 /* The device should always appear to be in use
233 * unless the driver suports autosuspend.
235 if (!udriver->supports_autosuspend)
236 error = usb_autoresume_device(udev);
239 error = udriver->probe(udev);
243 /* called from driver core with dev locked */
244 static int usb_unbind_device(struct device *dev)
246 struct usb_device *udev = to_usb_device(dev);
247 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
249 udriver->disconnect(udev);
250 if (!udriver->supports_autosuspend)
251 usb_autosuspend_device(udev);
256 * Cancel any pending scheduled resets
258 * [see usb_queue_reset_device()]
260 * Called after unconfiguring / when releasing interfaces. See
261 * comments in __usb_queue_reset_device() regarding
262 * udev->reset_running.
264 static void usb_cancel_queued_reset(struct usb_interface *iface)
266 if (iface->reset_running == 0)
267 cancel_work_sync(&iface->reset_ws);
270 /* called from driver core with dev locked */
271 static int usb_probe_interface(struct device *dev)
273 struct usb_driver *driver = to_usb_driver(dev->driver);
274 struct usb_interface *intf = to_usb_interface(dev);
275 struct usb_device *udev = interface_to_usbdev(intf);
276 const struct usb_device_id *id;
279 dev_dbg(dev, "%s\n", __func__);
281 intf->needs_binding = 0;
283 if (usb_device_is_owned(udev))
286 if (udev->authorized == 0) {
287 dev_err(&intf->dev, "Device is not authorized for usage\n");
291 id = usb_match_id(intf, driver->id_table);
293 id = usb_match_dynamic_id(intf, driver);
297 dev_dbg(dev, "%s - got id\n", __func__);
299 error = usb_autoresume_device(udev);
303 intf->condition = USB_INTERFACE_BINDING;
305 /* Probed interfaces are initially active. They are
306 * runtime-PM-enabled only if the driver has autosuspend support.
307 * They are sensitive to their children's power states.
309 pm_runtime_set_active(dev);
310 pm_suspend_ignore_children(dev, false);
311 if (driver->supports_autosuspend)
312 pm_runtime_enable(dev);
314 /* Carry out a deferred switch to altsetting 0 */
315 if (intf->needs_altsetting0) {
316 error = usb_set_interface(udev, intf->altsetting[0].
317 desc.bInterfaceNumber, 0);
320 intf->needs_altsetting0 = 0;
323 error = driver->probe(intf, id);
327 intf->condition = USB_INTERFACE_BOUND;
328 usb_autosuspend_device(udev);
332 intf->needs_remote_wakeup = 0;
333 intf->condition = USB_INTERFACE_UNBOUND;
334 usb_cancel_queued_reset(intf);
336 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
337 if (driver->supports_autosuspend)
338 pm_runtime_disable(dev);
339 pm_runtime_set_suspended(dev);
341 usb_autosuspend_device(udev);
345 /* called from driver core with dev locked */
346 static int usb_unbind_interface(struct device *dev)
348 struct usb_driver *driver = to_usb_driver(dev->driver);
349 struct usb_interface *intf = to_usb_interface(dev);
350 struct usb_device *udev;
353 intf->condition = USB_INTERFACE_UNBINDING;
355 /* Autoresume for set_interface call below */
356 udev = interface_to_usbdev(intf);
357 error = usb_autoresume_device(udev);
359 /* Terminate all URBs for this interface unless the driver
360 * supports "soft" unbinding.
362 if (!driver->soft_unbind)
363 usb_disable_interface(udev, intf, false);
365 driver->disconnect(intf);
366 usb_cancel_queued_reset(intf);
368 /* Reset other interface state.
369 * We cannot do a Set-Interface if the device is suspended or
370 * if it is prepared for a system sleep (since installing a new
371 * altsetting means creating new endpoint device entries).
372 * When either of these happens, defer the Set-Interface.
374 if (intf->cur_altsetting->desc.bAlternateSetting == 0) {
375 /* Already in altsetting 0 so skip Set-Interface.
376 * Just re-enable it without affecting the endpoint toggles.
378 usb_enable_interface(udev, intf, false);
379 } else if (!error && !intf->dev.power.is_prepared) {
380 r = usb_set_interface(udev, intf->altsetting[0].
381 desc.bInterfaceNumber, 0);
383 intf->needs_altsetting0 = 1;
385 intf->needs_altsetting0 = 1;
387 usb_set_intfdata(intf, NULL);
389 intf->condition = USB_INTERFACE_UNBOUND;
390 intf->needs_remote_wakeup = 0;
392 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
393 if (driver->supports_autosuspend)
394 pm_runtime_disable(dev);
395 pm_runtime_set_suspended(dev);
397 /* Undo any residual pm_autopm_get_interface_* calls */
398 for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r)
399 usb_autopm_put_interface_no_suspend(intf);
400 atomic_set(&intf->pm_usage_cnt, 0);
403 usb_autosuspend_device(udev);
409 * usb_driver_claim_interface - bind a driver to an interface
410 * @driver: the driver to be bound
411 * @iface: the interface to which it will be bound; must be in the
412 * usb device's active configuration
413 * @priv: driver data associated with that interface
415 * This is used by usb device drivers that need to claim more than one
416 * interface on a device when probing (audio and acm are current examples).
417 * No device driver should directly modify internal usb_interface or
418 * usb_device structure members.
420 * Few drivers should need to use this routine, since the most natural
421 * way to bind to an interface is to return the private data from
422 * the driver's probe() method.
424 * Callers must own the device lock, so driver probe() entries don't need
425 * extra locking, but other call contexts may need to explicitly claim that
428 int usb_driver_claim_interface(struct usb_driver *driver,
429 struct usb_interface *iface, void *priv)
431 struct device *dev = &iface->dev;
437 dev->driver = &driver->drvwrap.driver;
438 usb_set_intfdata(iface, priv);
439 iface->needs_binding = 0;
441 iface->condition = USB_INTERFACE_BOUND;
443 /* Claimed interfaces are initially inactive (suspended) and
444 * runtime-PM-enabled, but only if the driver has autosuspend
445 * support. Otherwise they are marked active, to prevent the
446 * device from being autosuspended, but left disabled. In either
447 * case they are sensitive to their children's power states.
449 pm_suspend_ignore_children(dev, false);
450 if (driver->supports_autosuspend)
451 pm_runtime_enable(dev);
453 pm_runtime_set_active(dev);
455 /* if interface was already added, bind now; else let
456 * the future device_add() bind it, bypassing probe()
458 if (device_is_registered(dev))
459 retval = device_bind_driver(dev);
463 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
466 * usb_driver_release_interface - unbind a driver from an interface
467 * @driver: the driver to be unbound
468 * @iface: the interface from which it will be unbound
470 * This can be used by drivers to release an interface without waiting
471 * for their disconnect() methods to be called. In typical cases this
472 * also causes the driver disconnect() method to be called.
474 * This call is synchronous, and may not be used in an interrupt context.
475 * Callers must own the device lock, so driver disconnect() entries don't
476 * need extra locking, but other call contexts may need to explicitly claim
479 void usb_driver_release_interface(struct usb_driver *driver,
480 struct usb_interface *iface)
482 struct device *dev = &iface->dev;
484 /* this should never happen, don't release something that's not ours */
485 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
488 /* don't release from within disconnect() */
489 if (iface->condition != USB_INTERFACE_BOUND)
491 iface->condition = USB_INTERFACE_UNBINDING;
493 /* Release via the driver core only if the interface
494 * has already been registered
496 if (device_is_registered(dev)) {
497 device_release_driver(dev);
500 usb_unbind_interface(dev);
505 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
507 /* returns 0 if no match, 1 if match */
508 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
510 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
511 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
514 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
515 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
518 /* No need to test id->bcdDevice_lo != 0, since 0 is never
519 greater than any unsigned number. */
520 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
521 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
524 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
525 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
528 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
529 (id->bDeviceClass != dev->descriptor.bDeviceClass))
532 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
533 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
536 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
537 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
543 /* returns 0 if no match, 1 if match */
544 int usb_match_one_id_intf(struct usb_device *dev,
545 struct usb_host_interface *intf,
546 const struct usb_device_id *id)
548 /* The interface class, subclass, and protocol should never be
549 * checked for a match if the device class is Vendor Specific,
550 * unless the match record specifies the Vendor ID. */
551 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
552 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
553 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
554 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
555 USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
558 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
559 (id->bInterfaceClass != intf->desc.bInterfaceClass))
562 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
563 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
566 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
567 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
573 /* returns 0 if no match, 1 if match */
574 int usb_match_one_id(struct usb_interface *interface,
575 const struct usb_device_id *id)
577 struct usb_host_interface *intf;
578 struct usb_device *dev;
580 /* proc_connectinfo in devio.c may call us with id == NULL. */
584 intf = interface->cur_altsetting;
585 dev = interface_to_usbdev(interface);
587 if (!usb_match_device(dev, id))
590 return usb_match_one_id_intf(dev, intf, id);
592 EXPORT_SYMBOL_GPL(usb_match_one_id);
595 * usb_match_id - find first usb_device_id matching device or interface
596 * @interface: the interface of interest
597 * @id: array of usb_device_id structures, terminated by zero entry
599 * usb_match_id searches an array of usb_device_id's and returns
600 * the first one matching the device or interface, or null.
601 * This is used when binding (or rebinding) a driver to an interface.
602 * Most USB device drivers will use this indirectly, through the usb core,
603 * but some layered driver frameworks use it directly.
604 * These device tables are exported with MODULE_DEVICE_TABLE, through
605 * modutils, to support the driver loading functionality of USB hotplugging.
609 * The "match_flags" element in a usb_device_id controls which
610 * members are used. If the corresponding bit is set, the
611 * value in the device_id must match its corresponding member
612 * in the device or interface descriptor, or else the device_id
615 * "driver_info" is normally used only by device drivers,
616 * but you can create a wildcard "matches anything" usb_device_id
617 * as a driver's "modules.usbmap" entry if you provide an id with
618 * only a nonzero "driver_info" field. If you do this, the USB device
619 * driver's probe() routine should use additional intelligence to
620 * decide whether to bind to the specified interface.
622 * What Makes Good usb_device_id Tables:
624 * The match algorithm is very simple, so that intelligence in
625 * driver selection must come from smart driver id records.
626 * Unless you have good reasons to use another selection policy,
627 * provide match elements only in related groups, and order match
628 * specifiers from specific to general. Use the macros provided
629 * for that purpose if you can.
631 * The most specific match specifiers use device descriptor
632 * data. These are commonly used with product-specific matches;
633 * the USB_DEVICE macro lets you provide vendor and product IDs,
634 * and you can also match against ranges of product revisions.
635 * These are widely used for devices with application or vendor
636 * specific bDeviceClass values.
638 * Matches based on device class/subclass/protocol specifications
639 * are slightly more general; use the USB_DEVICE_INFO macro, or
640 * its siblings. These are used with single-function devices
641 * where bDeviceClass doesn't specify that each interface has
644 * Matches based on interface class/subclass/protocol are the
645 * most general; they let drivers bind to any interface on a
646 * multiple-function device. Use the USB_INTERFACE_INFO
647 * macro, or its siblings, to match class-per-interface style
648 * devices (as recorded in bInterfaceClass).
650 * Note that an entry created by USB_INTERFACE_INFO won't match
651 * any interface if the device class is set to Vendor-Specific.
652 * This is deliberate; according to the USB spec the meanings of
653 * the interface class/subclass/protocol for these devices are also
654 * vendor-specific, and hence matching against a standard product
655 * class wouldn't work anyway. If you really want to use an
656 * interface-based match for such a device, create a match record
657 * that also specifies the vendor ID. (Unforunately there isn't a
658 * standard macro for creating records like this.)
660 * Within those groups, remember that not all combinations are
661 * meaningful. For example, don't give a product version range
662 * without vendor and product IDs; or specify a protocol without
663 * its associated class and subclass.
665 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
666 const struct usb_device_id *id)
668 /* proc_connectinfo in devio.c may call us with id == NULL. */
672 /* It is important to check that id->driver_info is nonzero,
673 since an entry that is all zeroes except for a nonzero
674 id->driver_info is the way to create an entry that
675 indicates that the driver want to examine every
676 device and interface. */
677 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
678 id->bInterfaceClass || id->driver_info; id++) {
679 if (usb_match_one_id(interface, id))
685 EXPORT_SYMBOL_GPL(usb_match_id);
687 static int usb_device_match(struct device *dev, struct device_driver *drv)
689 /* devices and interfaces are handled separately */
690 if (is_usb_device(dev)) {
692 /* interface drivers never match devices */
693 if (!is_usb_device_driver(drv))
696 /* TODO: Add real matching code */
699 } else if (is_usb_interface(dev)) {
700 struct usb_interface *intf;
701 struct usb_driver *usb_drv;
702 const struct usb_device_id *id;
704 /* device drivers never match interfaces */
705 if (is_usb_device_driver(drv))
708 intf = to_usb_interface(dev);
709 usb_drv = to_usb_driver(drv);
711 id = usb_match_id(intf, usb_drv->id_table);
715 id = usb_match_dynamic_id(intf, usb_drv);
723 #ifdef CONFIG_HOTPLUG
724 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
726 struct usb_device *usb_dev;
728 if (is_usb_device(dev)) {
729 usb_dev = to_usb_device(dev);
730 } else if (is_usb_interface(dev)) {
731 struct usb_interface *intf = to_usb_interface(dev);
733 usb_dev = interface_to_usbdev(intf);
738 if (usb_dev->devnum < 0) {
739 /* driver is often null here; dev_dbg() would oops */
740 pr_debug("usb %s: already deleted?\n", dev_name(dev));
744 pr_debug("usb %s: bus removed?\n", dev_name(dev));
748 #ifdef CONFIG_USB_DEVICEFS
749 /* If this is available, userspace programs can directly read
750 * all the device descriptors we don't tell them about. Or
751 * act as usermode drivers.
753 if (add_uevent_var(env, "DEVICE=/proc/bus/usb/%03d/%03d",
754 usb_dev->bus->busnum, usb_dev->devnum))
758 /* per-device configurations are common */
759 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
760 le16_to_cpu(usb_dev->descriptor.idVendor),
761 le16_to_cpu(usb_dev->descriptor.idProduct),
762 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
765 /* class-based driver binding models */
766 if (add_uevent_var(env, "TYPE=%d/%d/%d",
767 usb_dev->descriptor.bDeviceClass,
768 usb_dev->descriptor.bDeviceSubClass,
769 usb_dev->descriptor.bDeviceProtocol))
777 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
781 #endif /* CONFIG_HOTPLUG */
784 * usb_register_device_driver - register a USB device (not interface) driver
785 * @new_udriver: USB operations for the device driver
786 * @owner: module owner of this driver.
788 * Registers a USB device driver with the USB core. The list of
789 * unattached devices will be rescanned whenever a new driver is
790 * added, allowing the new driver to attach to any recognized devices.
791 * Returns a negative error code on failure and 0 on success.
793 int usb_register_device_driver(struct usb_device_driver *new_udriver,
794 struct module *owner)
801 new_udriver->drvwrap.for_devices = 1;
802 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
803 new_udriver->drvwrap.driver.bus = &usb_bus_type;
804 new_udriver->drvwrap.driver.probe = usb_probe_device;
805 new_udriver->drvwrap.driver.remove = usb_unbind_device;
806 new_udriver->drvwrap.driver.owner = owner;
808 retval = driver_register(&new_udriver->drvwrap.driver);
811 pr_info("%s: registered new device driver %s\n",
812 usbcore_name, new_udriver->name);
813 usbfs_update_special();
815 printk(KERN_ERR "%s: error %d registering device "
817 usbcore_name, retval, new_udriver->name);
822 EXPORT_SYMBOL_GPL(usb_register_device_driver);
825 * usb_deregister_device_driver - unregister a USB device (not interface) driver
826 * @udriver: USB operations of the device driver to unregister
827 * Context: must be able to sleep
829 * Unlinks the specified driver from the internal USB driver list.
831 void usb_deregister_device_driver(struct usb_device_driver *udriver)
833 pr_info("%s: deregistering device driver %s\n",
834 usbcore_name, udriver->name);
836 driver_unregister(&udriver->drvwrap.driver);
837 usbfs_update_special();
839 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
842 * usb_register_driver - register a USB interface driver
843 * @new_driver: USB operations for the interface driver
844 * @owner: module owner of this driver.
845 * @mod_name: module name string
847 * Registers a USB interface driver with the USB core. The list of
848 * unattached interfaces will be rescanned whenever a new driver is
849 * added, allowing the new driver to attach to any recognized interfaces.
850 * Returns a negative error code on failure and 0 on success.
852 * NOTE: if you want your driver to use the USB major number, you must call
853 * usb_register_dev() to enable that functionality. This function no longer
854 * takes care of that.
856 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
857 const char *mod_name)
864 new_driver->drvwrap.for_devices = 0;
865 new_driver->drvwrap.driver.name = (char *) new_driver->name;
866 new_driver->drvwrap.driver.bus = &usb_bus_type;
867 new_driver->drvwrap.driver.probe = usb_probe_interface;
868 new_driver->drvwrap.driver.remove = usb_unbind_interface;
869 new_driver->drvwrap.driver.owner = owner;
870 new_driver->drvwrap.driver.mod_name = mod_name;
871 spin_lock_init(&new_driver->dynids.lock);
872 INIT_LIST_HEAD(&new_driver->dynids.list);
874 retval = driver_register(&new_driver->drvwrap.driver);
878 usbfs_update_special();
880 retval = usb_create_newid_file(new_driver);
884 retval = usb_create_removeid_file(new_driver);
888 pr_info("%s: registered new interface driver %s\n",
889 usbcore_name, new_driver->name);
895 usb_remove_newid_file(new_driver);
897 driver_unregister(&new_driver->drvwrap.driver);
899 printk(KERN_ERR "%s: error %d registering interface "
901 usbcore_name, retval, new_driver->name);
904 EXPORT_SYMBOL_GPL(usb_register_driver);
907 * usb_deregister - unregister a USB interface driver
908 * @driver: USB operations of the interface driver to unregister
909 * Context: must be able to sleep
911 * Unlinks the specified driver from the internal USB driver list.
913 * NOTE: If you called usb_register_dev(), you still need to call
914 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
915 * this * call will no longer do it for you.
917 void usb_deregister(struct usb_driver *driver)
919 pr_info("%s: deregistering interface driver %s\n",
920 usbcore_name, driver->name);
922 usb_remove_removeid_file(driver);
923 usb_remove_newid_file(driver);
924 usb_free_dynids(driver);
925 driver_unregister(&driver->drvwrap.driver);
927 usbfs_update_special();
929 EXPORT_SYMBOL_GPL(usb_deregister);
931 /* Forced unbinding of a USB interface driver, either because
932 * it doesn't support pre_reset/post_reset/reset_resume or
933 * because it doesn't support suspend/resume.
935 * The caller must hold @intf's device's lock, but not its pm_mutex
936 * and not @intf->dev.sem.
938 void usb_forced_unbind_intf(struct usb_interface *intf)
940 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
942 dev_dbg(&intf->dev, "forced unbind\n");
943 usb_driver_release_interface(driver, intf);
945 /* Mark the interface for later rebinding */
946 intf->needs_binding = 1;
949 /* Delayed forced unbinding of a USB interface driver and scan
952 * The caller must hold @intf's device's lock, but not its pm_mutex
953 * and not @intf->dev.sem.
955 * Note: Rebinds will be skipped if a system sleep transition is in
956 * progress and the PM "complete" callback hasn't occurred yet.
958 void usb_rebind_intf(struct usb_interface *intf)
962 /* Delayed unbind of an existing driver */
963 if (intf->dev.driver) {
964 struct usb_driver *driver =
965 to_usb_driver(intf->dev.driver);
967 dev_dbg(&intf->dev, "forced unbind\n");
968 usb_driver_release_interface(driver, intf);
971 /* Try to rebind the interface */
972 if (!intf->dev.power.is_prepared) {
973 intf->needs_binding = 0;
974 rc = device_attach(&intf->dev);
976 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
985 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
986 * or rebind interfaces that have been unbound, according to @action.
988 * The caller must hold @udev's device lock.
990 static void do_unbind_rebind(struct usb_device *udev, int action)
992 struct usb_host_config *config;
994 struct usb_interface *intf;
995 struct usb_driver *drv;
997 config = udev->actconfig;
999 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1000 intf = config->interface[i];
1003 if (intf->dev.driver) {
1004 drv = to_usb_driver(intf->dev.driver);
1005 if (!drv->suspend || !drv->resume)
1006 usb_forced_unbind_intf(intf);
1010 if (intf->needs_binding)
1011 usb_rebind_intf(intf);
1018 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
1020 struct usb_device_driver *udriver;
1023 if (udev->state == USB_STATE_NOTATTACHED ||
1024 udev->state == USB_STATE_SUSPENDED)
1027 /* For devices that don't have a driver, we do a generic suspend. */
1028 if (udev->dev.driver)
1029 udriver = to_usb_device_driver(udev->dev.driver);
1031 udev->do_remote_wakeup = 0;
1032 udriver = &usb_generic_driver;
1034 status = udriver->suspend(udev, msg);
1037 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1041 static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1043 struct usb_device_driver *udriver;
1046 if (udev->state == USB_STATE_NOTATTACHED)
1049 /* Can't resume it if it doesn't have a driver. */
1050 if (udev->dev.driver == NULL) {
1055 /* Non-root devices on a full/low-speed bus must wait for their
1056 * companion high-speed root hub, in case a handoff is needed.
1058 if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion)
1059 device_pm_wait_for_dev(&udev->dev,
1060 &udev->bus->hs_companion->root_hub->dev);
1062 if (udev->quirks & USB_QUIRK_RESET_RESUME)
1063 udev->reset_resume = 1;
1065 udriver = to_usb_device_driver(udev->dev.driver);
1066 status = udriver->resume(udev, msg);
1069 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1073 static int usb_suspend_interface(struct usb_device *udev,
1074 struct usb_interface *intf, pm_message_t msg)
1076 struct usb_driver *driver;
1079 if (udev->state == USB_STATE_NOTATTACHED ||
1080 intf->condition == USB_INTERFACE_UNBOUND)
1082 driver = to_usb_driver(intf->dev.driver);
1084 if (driver->suspend) {
1085 status = driver->suspend(intf, msg);
1086 if (status && !PMSG_IS_AUTO(msg))
1087 dev_err(&intf->dev, "%s error %d\n",
1090 /* Later we will unbind the driver and reprobe */
1091 intf->needs_binding = 1;
1092 dev_warn(&intf->dev, "no %s for driver %s?\n",
1093 "suspend", driver->name);
1097 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1101 static int usb_resume_interface(struct usb_device *udev,
1102 struct usb_interface *intf, pm_message_t msg, int reset_resume)
1104 struct usb_driver *driver;
1107 if (udev->state == USB_STATE_NOTATTACHED)
1110 /* Don't let autoresume interfere with unbinding */
1111 if (intf->condition == USB_INTERFACE_UNBINDING)
1114 /* Can't resume it if it doesn't have a driver. */
1115 if (intf->condition == USB_INTERFACE_UNBOUND) {
1117 /* Carry out a deferred switch to altsetting 0 */
1118 if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1119 usb_set_interface(udev, intf->altsetting[0].
1120 desc.bInterfaceNumber, 0);
1121 intf->needs_altsetting0 = 0;
1126 /* Don't resume if the interface is marked for rebinding */
1127 if (intf->needs_binding)
1129 driver = to_usb_driver(intf->dev.driver);
1132 if (driver->reset_resume) {
1133 status = driver->reset_resume(intf);
1135 dev_err(&intf->dev, "%s error %d\n",
1136 "reset_resume", status);
1138 intf->needs_binding = 1;
1139 dev_warn(&intf->dev, "no %s for driver %s?\n",
1140 "reset_resume", driver->name);
1143 if (driver->resume) {
1144 status = driver->resume(intf);
1146 dev_err(&intf->dev, "%s error %d\n",
1149 intf->needs_binding = 1;
1150 dev_warn(&intf->dev, "no %s for driver %s?\n",
1151 "resume", driver->name);
1156 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1158 /* Later we will unbind the driver and/or reprobe, if necessary */
1163 * usb_suspend_both - suspend a USB device and its interfaces
1164 * @udev: the usb_device to suspend
1165 * @msg: Power Management message describing this state transition
1167 * This is the central routine for suspending USB devices. It calls the
1168 * suspend methods for all the interface drivers in @udev and then calls
1169 * the suspend method for @udev itself. If an error occurs at any stage,
1170 * all the interfaces which were suspended are resumed so that they remain
1171 * in the same state as the device.
1173 * Autosuspend requests originating from a child device or an interface
1174 * driver may be made without the protection of @udev's device lock, but
1175 * all other suspend calls will hold the lock. Usbcore will insure that
1176 * method calls do not arrive during bind, unbind, or reset operations.
1177 * However drivers must be prepared to handle suspend calls arriving at
1178 * unpredictable times.
1180 * This routine can run only in process context.
1182 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1186 struct usb_interface *intf;
1188 if (udev->state == USB_STATE_NOTATTACHED ||
1189 udev->state == USB_STATE_SUSPENDED)
1192 /* Suspend all the interfaces and then udev itself */
1193 if (udev->actconfig) {
1194 n = udev->actconfig->desc.bNumInterfaces;
1195 for (i = n - 1; i >= 0; --i) {
1196 intf = udev->actconfig->interface[i];
1197 status = usb_suspend_interface(udev, intf, msg);
1199 /* Ignore errors during system sleep transitions */
1200 if (!PMSG_IS_AUTO(msg))
1207 status = usb_suspend_device(udev, msg);
1210 * Ignore errors from non-root-hub devices during
1211 * system sleep transitions. For the most part,
1212 * these devices should go to low power anyway when
1213 * the entire bus is suspended.
1215 if (udev->parent && !PMSG_IS_AUTO(msg))
1219 /* If the suspend failed, resume interfaces that did get suspended */
1221 msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1223 intf = udev->actconfig->interface[i];
1224 usb_resume_interface(udev, intf, msg, 0);
1227 /* If the suspend succeeded then prevent any more URB submissions
1228 * and flush any outstanding URBs.
1231 udev->can_submit = 0;
1232 for (i = 0; i < 16; ++i) {
1233 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1234 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1239 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1244 * usb_resume_both - resume a USB device and its interfaces
1245 * @udev: the usb_device to resume
1246 * @msg: Power Management message describing this state transition
1248 * This is the central routine for resuming USB devices. It calls the
1249 * the resume method for @udev and then calls the resume methods for all
1250 * the interface drivers in @udev.
1252 * Autoresume requests originating from a child device or an interface
1253 * driver may be made without the protection of @udev's device lock, but
1254 * all other resume calls will hold the lock. Usbcore will insure that
1255 * method calls do not arrive during bind, unbind, or reset operations.
1256 * However drivers must be prepared to handle resume calls arriving at
1257 * unpredictable times.
1259 * This routine can run only in process context.
1261 static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1265 struct usb_interface *intf;
1267 if (udev->state == USB_STATE_NOTATTACHED) {
1271 udev->can_submit = 1;
1273 /* Resume the device */
1274 if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume)
1275 status = usb_resume_device(udev, msg);
1277 /* Resume the interfaces */
1278 if (status == 0 && udev->actconfig) {
1279 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1280 intf = udev->actconfig->interface[i];
1281 usb_resume_interface(udev, intf, msg,
1282 udev->reset_resume);
1285 usb_mark_last_busy(udev);
1288 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1290 udev->reset_resume = 0;
1294 static void choose_wakeup(struct usb_device *udev, pm_message_t msg)
1298 /* Remote wakeup is needed only when we actually go to sleep.
1299 * For things like FREEZE and QUIESCE, if the device is already
1300 * autosuspended then its current wakeup setting is okay.
1302 if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
1303 if (udev->state != USB_STATE_SUSPENDED)
1304 udev->do_remote_wakeup = 0;
1308 /* Enable remote wakeup if it is allowed, even if no interface drivers
1311 w = device_may_wakeup(&udev->dev);
1313 /* If the device is autosuspended with the wrong wakeup setting,
1314 * autoresume now so the setting can be changed.
1316 if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup)
1317 pm_runtime_resume(&udev->dev);
1318 udev->do_remote_wakeup = w;
1321 /* The device lock is held by the PM core */
1322 int usb_suspend(struct device *dev, pm_message_t msg)
1324 struct usb_device *udev = to_usb_device(dev);
1326 do_unbind_rebind(udev, DO_UNBIND);
1327 choose_wakeup(udev, msg);
1328 return usb_suspend_both(udev, msg);
1331 /* The device lock is held by the PM core */
1332 int usb_resume(struct device *dev, pm_message_t msg)
1334 struct usb_device *udev = to_usb_device(dev);
1337 /* For PM complete calls, all we do is rebind interfaces */
1338 if (msg.event == PM_EVENT_ON) {
1339 if (udev->state != USB_STATE_NOTATTACHED)
1340 do_unbind_rebind(udev, DO_REBIND);
1343 /* For all other calls, take the device back to full power and
1344 * tell the PM core in case it was autosuspended previously.
1345 * Unbind the interfaces that will need rebinding later.
1348 status = usb_resume_both(udev, msg);
1350 pm_runtime_disable(dev);
1351 pm_runtime_set_active(dev);
1352 pm_runtime_enable(dev);
1353 do_unbind_rebind(udev, DO_REBIND);
1357 /* Avoid PM error messages for devices disconnected while suspended
1358 * as we'll display regular disconnect messages just a bit later.
1360 if (status == -ENODEV || status == -ESHUTDOWN)
1365 #endif /* CONFIG_PM */
1367 #ifdef CONFIG_USB_SUSPEND
1370 * usb_enable_autosuspend - allow a USB device to be autosuspended
1371 * @udev: the USB device which may be autosuspended
1373 * This routine allows @udev to be autosuspended. An autosuspend won't
1374 * take place until the autosuspend_delay has elapsed and all the other
1375 * necessary conditions are satisfied.
1377 * The caller must hold @udev's device lock.
1379 void usb_enable_autosuspend(struct usb_device *udev)
1381 pm_runtime_allow(&udev->dev);
1383 EXPORT_SYMBOL_GPL(usb_enable_autosuspend);
1386 * usb_disable_autosuspend - prevent a USB device from being autosuspended
1387 * @udev: the USB device which may not be autosuspended
1389 * This routine prevents @udev from being autosuspended and wakes it up
1390 * if it is already autosuspended.
1392 * The caller must hold @udev's device lock.
1394 void usb_disable_autosuspend(struct usb_device *udev)
1396 pm_runtime_forbid(&udev->dev);
1398 EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
1401 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1402 * @udev: the usb_device to autosuspend
1404 * This routine should be called when a core subsystem is finished using
1405 * @udev and wants to allow it to autosuspend. Examples would be when
1406 * @udev's device file in usbfs is closed or after a configuration change.
1408 * @udev's usage counter is decremented; if it drops to 0 and all the
1409 * interfaces are inactive then a delayed autosuspend will be attempted.
1410 * The attempt may fail (see autosuspend_check()).
1412 * The caller must hold @udev's device lock.
1414 * This routine can run only in process context.
1416 void usb_autosuspend_device(struct usb_device *udev)
1420 usb_mark_last_busy(udev);
1421 status = pm_runtime_put_sync_autosuspend(&udev->dev);
1422 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1423 __func__, atomic_read(&udev->dev.power.usage_count),
1428 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1429 * @udev: the usb_device to autoresume
1431 * This routine should be called when a core subsystem wants to use @udev
1432 * and needs to guarantee that it is not suspended. No autosuspend will
1433 * occur until usb_autosuspend_device() is called. (Note that this will
1434 * not prevent suspend events originating in the PM core.) Examples would
1435 * be when @udev's device file in usbfs is opened or when a remote-wakeup
1436 * request is received.
1438 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1439 * However if the autoresume fails then the usage counter is re-decremented.
1441 * The caller must hold @udev's device lock.
1443 * This routine can run only in process context.
1445 int usb_autoresume_device(struct usb_device *udev)
1449 status = pm_runtime_get_sync(&udev->dev);
1451 pm_runtime_put_sync(&udev->dev);
1452 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1453 __func__, atomic_read(&udev->dev.power.usage_count),
1461 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1462 * @intf: the usb_interface whose counter should be decremented
1464 * This routine should be called by an interface driver when it is
1465 * finished using @intf and wants to allow it to autosuspend. A typical
1466 * example would be a character-device driver when its device file is
1469 * The routine decrements @intf's usage counter. When the counter reaches
1470 * 0, a delayed autosuspend request for @intf's device is attempted. The
1471 * attempt may fail (see autosuspend_check()).
1473 * This routine can run only in process context.
1475 void usb_autopm_put_interface(struct usb_interface *intf)
1477 struct usb_device *udev = interface_to_usbdev(intf);
1480 usb_mark_last_busy(udev);
1481 atomic_dec(&intf->pm_usage_cnt);
1482 status = pm_runtime_put_sync(&intf->dev);
1483 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1484 __func__, atomic_read(&intf->dev.power.usage_count),
1487 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1490 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1491 * @intf: the usb_interface whose counter should be decremented
1493 * This routine does much the same thing as usb_autopm_put_interface():
1494 * It decrements @intf's usage counter and schedules a delayed
1495 * autosuspend request if the counter is <= 0. The difference is that it
1496 * does not perform any synchronization; callers should hold a private
1497 * lock and handle all synchronization issues themselves.
1499 * Typically a driver would call this routine during an URB's completion
1500 * handler, if no more URBs were pending.
1502 * This routine can run in atomic context.
1504 void usb_autopm_put_interface_async(struct usb_interface *intf)
1506 struct usb_device *udev = interface_to_usbdev(intf);
1509 usb_mark_last_busy(udev);
1510 atomic_dec(&intf->pm_usage_cnt);
1511 status = pm_runtime_put(&intf->dev);
1512 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1513 __func__, atomic_read(&intf->dev.power.usage_count),
1516 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1519 * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
1520 * @intf: the usb_interface whose counter should be decremented
1522 * This routine decrements @intf's usage counter but does not carry out an
1525 * This routine can run in atomic context.
1527 void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
1529 struct usb_device *udev = interface_to_usbdev(intf);
1531 usb_mark_last_busy(udev);
1532 atomic_dec(&intf->pm_usage_cnt);
1533 pm_runtime_put_noidle(&intf->dev);
1535 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
1538 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1539 * @intf: the usb_interface whose counter should be incremented
1541 * This routine should be called by an interface driver when it wants to
1542 * use @intf and needs to guarantee that it is not suspended. In addition,
1543 * the routine prevents @intf from being autosuspended subsequently. (Note
1544 * that this will not prevent suspend events originating in the PM core.)
1545 * This prevention will persist until usb_autopm_put_interface() is called
1546 * or @intf is unbound. A typical example would be a character-device
1547 * driver when its device file is opened.
1549 * @intf's usage counter is incremented to prevent subsequent autosuspends.
1550 * However if the autoresume fails then the counter is re-decremented.
1552 * This routine can run only in process context.
1554 int usb_autopm_get_interface(struct usb_interface *intf)
1558 status = pm_runtime_get_sync(&intf->dev);
1560 pm_runtime_put_sync(&intf->dev);
1562 atomic_inc(&intf->pm_usage_cnt);
1563 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1564 __func__, atomic_read(&intf->dev.power.usage_count),
1570 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1573 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1574 * @intf: the usb_interface whose counter should be incremented
1576 * This routine does much the same thing as
1577 * usb_autopm_get_interface(): It increments @intf's usage counter and
1578 * queues an autoresume request if the device is suspended. The
1579 * differences are that it does not perform any synchronization (callers
1580 * should hold a private lock and handle all synchronization issues
1581 * themselves), and it does not autoresume the device directly (it only
1582 * queues a request). After a successful call, the device may not yet be
1585 * This routine can run in atomic context.
1587 int usb_autopm_get_interface_async(struct usb_interface *intf)
1591 status = pm_runtime_get(&intf->dev);
1592 if (status < 0 && status != -EINPROGRESS)
1593 pm_runtime_put_noidle(&intf->dev);
1595 atomic_inc(&intf->pm_usage_cnt);
1596 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1597 __func__, atomic_read(&intf->dev.power.usage_count),
1599 if (status > 0 || status == -EINPROGRESS)
1603 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1606 * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
1607 * @intf: the usb_interface whose counter should be incremented
1609 * This routine increments @intf's usage counter but does not carry out an
1612 * This routine can run in atomic context.
1614 void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
1616 struct usb_device *udev = interface_to_usbdev(intf);
1618 usb_mark_last_busy(udev);
1619 atomic_inc(&intf->pm_usage_cnt);
1620 pm_runtime_get_noresume(&intf->dev);
1622 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
1624 /* Internal routine to check whether we may autosuspend a device. */
1625 static int autosuspend_check(struct usb_device *udev)
1628 struct usb_interface *intf;
1630 /* Fail if autosuspend is disabled, or any interfaces are in use, or
1631 * any interface drivers require remote wakeup but it isn't available.
1634 if (udev->actconfig) {
1635 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1636 intf = udev->actconfig->interface[i];
1638 /* We don't need to check interfaces that are
1639 * disabled for runtime PM. Either they are unbound
1640 * or else their drivers don't support autosuspend
1641 * and so they are permanently active.
1643 if (intf->dev.power.disable_depth)
1645 if (atomic_read(&intf->dev.power.usage_count) > 0)
1647 w |= intf->needs_remote_wakeup;
1649 /* Don't allow autosuspend if the device will need
1650 * a reset-resume and any of its interface drivers
1651 * doesn't include support or needs remote wakeup.
1653 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1654 struct usb_driver *driver;
1656 driver = to_usb_driver(intf->dev.driver);
1657 if (!driver->reset_resume ||
1658 intf->needs_remote_wakeup)
1663 if (w && !device_can_wakeup(&udev->dev)) {
1664 dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
1667 udev->do_remote_wakeup = w;
1671 int usb_runtime_suspend(struct device *dev)
1673 struct usb_device *udev = to_usb_device(dev);
1676 /* A USB device can be suspended if it passes the various autosuspend
1677 * checks. Runtime suspend for a USB device means suspending all the
1678 * interfaces and then the device itself.
1680 if (autosuspend_check(udev) != 0)
1683 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1685 /* Allow a retry if autosuspend failed temporarily */
1686 if (status == -EAGAIN || status == -EBUSY)
1687 usb_mark_last_busy(udev);
1690 * The PM core reacts badly unless the return code is 0,
1691 * -EAGAIN, or -EBUSY, so always return -EBUSY on an error
1692 * (except for root hubs, because they don't suspend through
1693 * an upstream port like other USB devices).
1695 if (status != 0 && udev->parent)
1700 int usb_runtime_resume(struct device *dev)
1702 struct usb_device *udev = to_usb_device(dev);
1705 /* Runtime resume for a USB device means resuming both the device
1706 * and all its interfaces.
1708 status = usb_resume_both(udev, PMSG_AUTO_RESUME);
1712 int usb_runtime_idle(struct device *dev)
1714 struct usb_device *udev = to_usb_device(dev);
1716 /* An idle USB device can be suspended if it passes the various
1717 * autosuspend checks.
1719 if (autosuspend_check(udev) == 0)
1720 pm_runtime_autosuspend(dev);
1724 int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
1726 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1729 if (hcd->driver->set_usb2_hw_lpm) {
1730 ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable);
1732 udev->usb2_hw_lpm_enabled = enable;
1738 #endif /* CONFIG_USB_SUSPEND */
1740 struct bus_type usb_bus_type = {
1742 .match = usb_device_match,
1743 .uevent = usb_uevent,