2 * drivers/usb/driver.c - most of the driver model stuff for usb
4 * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
6 * based on drivers/usb/usb.c which had the following copyrights:
7 * (C) Copyright Linus Torvalds 1999
8 * (C) Copyright Johannes Erdfelt 1999-2001
9 * (C) Copyright Andreas Gal 1999
10 * (C) Copyright Gregory P. Smith 1999
11 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
12 * (C) Copyright Randy Dunlap 2000
13 * (C) Copyright David Brownell 2000-2004
14 * (C) Copyright Yggdrasil Computing, Inc. 2000
15 * (usb_device_id matching changes by Adam J. Richter)
16 * (C) Copyright Greg Kroah-Hartman 2002-2003
18 * NOTE! This is not actually a driver at all, rather this is
19 * just a collection of helper routines that implement the
20 * matching, probing, releasing, suspending and resuming for
25 #include <linux/device.h>
26 #include <linux/usb.h>
27 #include <linux/usb/quirks.h>
28 #include <linux/workqueue.h>
36 * Adds a new dynamic USBdevice ID to this driver,
37 * and cause the driver to probe for all devices again.
39 ssize_t usb_store_new_id(struct usb_dynids *dynids,
40 struct device_driver *driver,
41 const char *buf, size_t count)
43 struct usb_dynid *dynid;
49 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
53 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
57 INIT_LIST_HEAD(&dynid->node);
58 dynid->id.idVendor = idVendor;
59 dynid->id.idProduct = idProduct;
60 dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
62 spin_lock(&dynids->lock);
63 list_add_tail(&dynid->node, &dynids->list);
64 spin_unlock(&dynids->lock);
66 if (get_driver(driver)) {
67 retval = driver_attach(driver);
75 EXPORT_SYMBOL_GPL(usb_store_new_id);
77 static ssize_t store_new_id(struct device_driver *driver,
78 const char *buf, size_t count)
80 struct usb_driver *usb_drv = to_usb_driver(driver);
82 return usb_store_new_id(&usb_drv->dynids, driver, buf, count);
84 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
86 static int usb_create_newid_file(struct usb_driver *usb_drv)
90 if (usb_drv->no_dynamic_id)
93 if (usb_drv->probe != NULL)
94 error = driver_create_file(&usb_drv->drvwrap.driver,
100 static void usb_remove_newid_file(struct usb_driver *usb_drv)
102 if (usb_drv->no_dynamic_id)
105 if (usb_drv->probe != NULL)
106 driver_remove_file(&usb_drv->drvwrap.driver,
107 &driver_attr_new_id);
110 static void usb_free_dynids(struct usb_driver *usb_drv)
112 struct usb_dynid *dynid, *n;
114 spin_lock(&usb_drv->dynids.lock);
115 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
116 list_del(&dynid->node);
119 spin_unlock(&usb_drv->dynids.lock);
122 static inline int usb_create_newid_file(struct usb_driver *usb_drv)
127 static void usb_remove_newid_file(struct usb_driver *usb_drv)
131 static inline void usb_free_dynids(struct usb_driver *usb_drv)
136 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
137 struct usb_driver *drv)
139 struct usb_dynid *dynid;
141 spin_lock(&drv->dynids.lock);
142 list_for_each_entry(dynid, &drv->dynids.list, node) {
143 if (usb_match_one_id(intf, &dynid->id)) {
144 spin_unlock(&drv->dynids.lock);
148 spin_unlock(&drv->dynids.lock);
153 /* called from driver core with dev locked */
154 static int usb_probe_device(struct device *dev)
156 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
157 struct usb_device *udev;
160 dev_dbg(dev, "%s\n", __func__);
162 if (!is_usb_device(dev)) /* Sanity check */
165 udev = to_usb_device(dev);
167 /* TODO: Add real matching code */
169 /* The device should always appear to be in use
170 * unless the driver suports autosuspend.
172 udev->pm_usage_cnt = !(udriver->supports_autosuspend);
174 error = udriver->probe(udev);
178 /* called from driver core with dev locked */
179 static int usb_unbind_device(struct device *dev)
181 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
183 udriver->disconnect(to_usb_device(dev));
188 * Cancel any pending scheduled resets
190 * [see usb_queue_reset_device()]
192 * Called after unconfiguring / when releasing interfaces. See
193 * comments in __usb_queue_reset_device() regarding
194 * udev->reset_running.
196 static void usb_cancel_queued_reset(struct usb_interface *iface)
198 if (iface->reset_running == 0)
199 cancel_work_sync(&iface->reset_ws);
202 /* called from driver core with dev locked */
203 static int usb_probe_interface(struct device *dev)
205 struct usb_driver *driver = to_usb_driver(dev->driver);
206 struct usb_interface *intf;
207 struct usb_device *udev;
208 const struct usb_device_id *id;
211 dev_dbg(dev, "%s\n", __func__);
213 if (is_usb_device(dev)) /* Sanity check */
216 intf = to_usb_interface(dev);
217 udev = interface_to_usbdev(intf);
218 intf->needs_binding = 0;
220 if (udev->authorized == 0) {
221 dev_err(&intf->dev, "Device is not authorized for usage\n");
225 id = usb_match_id(intf, driver->id_table);
227 id = usb_match_dynamic_id(intf, driver);
229 dev_dbg(dev, "%s - got id\n", __func__);
231 error = usb_autoresume_device(udev);
235 /* Interface "power state" doesn't correspond to any hardware
236 * state whatsoever. We use it to record when it's bound to
237 * a driver that may start I/0: it's not frozen/quiesced.
240 intf->condition = USB_INTERFACE_BINDING;
242 /* The interface should always appear to be in use
243 * unless the driver suports autosuspend.
245 intf->pm_usage_cnt = !(driver->supports_autosuspend);
247 /* Carry out a deferred switch to altsetting 0 */
248 if (intf->needs_altsetting0) {
249 usb_set_interface(udev, intf->altsetting[0].
250 desc.bInterfaceNumber, 0);
251 intf->needs_altsetting0 = 0;
254 error = driver->probe(intf, id);
257 intf->needs_remote_wakeup = 0;
258 intf->condition = USB_INTERFACE_UNBOUND;
259 usb_cancel_queued_reset(intf);
261 intf->condition = USB_INTERFACE_BOUND;
263 usb_autosuspend_device(udev);
269 /* called from driver core with dev locked */
270 static int usb_unbind_interface(struct device *dev)
272 struct usb_driver *driver = to_usb_driver(dev->driver);
273 struct usb_interface *intf = to_usb_interface(dev);
274 struct usb_device *udev;
277 intf->condition = USB_INTERFACE_UNBINDING;
279 /* Autoresume for set_interface call below */
280 udev = interface_to_usbdev(intf);
281 error = usb_autoresume_device(udev);
283 /* Terminate all URBs for this interface unless the driver
284 * supports "soft" unbinding.
286 if (!driver->soft_unbind)
287 usb_disable_interface(udev, intf);
289 driver->disconnect(intf);
290 usb_cancel_queued_reset(intf);
292 /* Reset other interface state.
293 * We cannot do a Set-Interface if the device is suspended or
294 * if it is prepared for a system sleep (since installing a new
295 * altsetting means creating new endpoint device entries).
296 * When either of these happens, defer the Set-Interface.
298 if (intf->cur_altsetting->desc.bAlternateSetting == 0)
299 ; /* Already in altsetting 0 so skip Set-Interface */
300 else if (!error && intf->dev.power.status == DPM_ON)
301 usb_set_interface(udev, intf->altsetting[0].
302 desc.bInterfaceNumber, 0);
304 intf->needs_altsetting0 = 1;
305 usb_set_intfdata(intf, NULL);
307 intf->condition = USB_INTERFACE_UNBOUND;
309 intf->needs_remote_wakeup = 0;
312 usb_autosuspend_device(udev);
318 * usb_driver_claim_interface - bind a driver to an interface
319 * @driver: the driver to be bound
320 * @iface: the interface to which it will be bound; must be in the
321 * usb device's active configuration
322 * @priv: driver data associated with that interface
324 * This is used by usb device drivers that need to claim more than one
325 * interface on a device when probing (audio and acm are current examples).
326 * No device driver should directly modify internal usb_interface or
327 * usb_device structure members.
329 * Few drivers should need to use this routine, since the most natural
330 * way to bind to an interface is to return the private data from
331 * the driver's probe() method.
333 * Callers must own the device lock, so driver probe() entries don't need
334 * extra locking, but other call contexts may need to explicitly claim that
337 int usb_driver_claim_interface(struct usb_driver *driver,
338 struct usb_interface *iface, void *priv)
340 struct device *dev = &iface->dev;
341 struct usb_device *udev = interface_to_usbdev(iface);
347 dev->driver = &driver->drvwrap.driver;
348 usb_set_intfdata(iface, priv);
349 iface->needs_binding = 0;
352 iface->condition = USB_INTERFACE_BOUND;
354 iface->pm_usage_cnt = !(driver->supports_autosuspend);
357 /* if interface was already added, bind now; else let
358 * the future device_add() bind it, bypassing probe()
360 if (device_is_registered(dev))
361 retval = device_bind_driver(dev);
365 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
368 * usb_driver_release_interface - unbind a driver from an interface
369 * @driver: the driver to be unbound
370 * @iface: the interface from which it will be unbound
372 * This can be used by drivers to release an interface without waiting
373 * for their disconnect() methods to be called. In typical cases this
374 * also causes the driver disconnect() method to be called.
376 * This call is synchronous, and may not be used in an interrupt context.
377 * Callers must own the device lock, so driver disconnect() entries don't
378 * need extra locking, but other call contexts may need to explicitly claim
381 void usb_driver_release_interface(struct usb_driver *driver,
382 struct usb_interface *iface)
384 struct device *dev = &iface->dev;
385 struct usb_device *udev = interface_to_usbdev(iface);
387 /* this should never happen, don't release something that's not ours */
388 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
391 /* don't release from within disconnect() */
392 if (iface->condition != USB_INTERFACE_BOUND)
395 /* don't release if the interface hasn't been added yet */
396 if (device_is_registered(dev)) {
397 iface->condition = USB_INTERFACE_UNBINDING;
398 device_release_driver(dev);
400 iface->condition = USB_INTERFACE_UNBOUND;
401 usb_cancel_queued_reset(iface);
404 usb_set_intfdata(iface, NULL);
407 iface->condition = USB_INTERFACE_UNBOUND;
408 mark_quiesced(iface);
409 iface->needs_remote_wakeup = 0;
412 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
414 /* returns 0 if no match, 1 if match */
415 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
417 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
418 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
421 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
422 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
425 /* No need to test id->bcdDevice_lo != 0, since 0 is never
426 greater than any unsigned number. */
427 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
428 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
431 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
432 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
435 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
436 (id->bDeviceClass != dev->descriptor.bDeviceClass))
439 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
440 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
443 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
444 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
450 /* returns 0 if no match, 1 if match */
451 int usb_match_one_id(struct usb_interface *interface,
452 const struct usb_device_id *id)
454 struct usb_host_interface *intf;
455 struct usb_device *dev;
457 /* proc_connectinfo in devio.c may call us with id == NULL. */
461 intf = interface->cur_altsetting;
462 dev = interface_to_usbdev(interface);
464 if (!usb_match_device(dev, id))
467 /* The interface class, subclass, and protocol should never be
468 * checked for a match if the device class is Vendor Specific,
469 * unless the match record specifies the Vendor ID. */
470 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
471 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
472 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
473 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
474 USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
477 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
478 (id->bInterfaceClass != intf->desc.bInterfaceClass))
481 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
482 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
485 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
486 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
491 EXPORT_SYMBOL_GPL(usb_match_one_id);
494 * usb_match_id - find first usb_device_id matching device or interface
495 * @interface: the interface of interest
496 * @id: array of usb_device_id structures, terminated by zero entry
498 * usb_match_id searches an array of usb_device_id's and returns
499 * the first one matching the device or interface, or null.
500 * This is used when binding (or rebinding) a driver to an interface.
501 * Most USB device drivers will use this indirectly, through the usb core,
502 * but some layered driver frameworks use it directly.
503 * These device tables are exported with MODULE_DEVICE_TABLE, through
504 * modutils, to support the driver loading functionality of USB hotplugging.
508 * The "match_flags" element in a usb_device_id controls which
509 * members are used. If the corresponding bit is set, the
510 * value in the device_id must match its corresponding member
511 * in the device or interface descriptor, or else the device_id
514 * "driver_info" is normally used only by device drivers,
515 * but you can create a wildcard "matches anything" usb_device_id
516 * as a driver's "modules.usbmap" entry if you provide an id with
517 * only a nonzero "driver_info" field. If you do this, the USB device
518 * driver's probe() routine should use additional intelligence to
519 * decide whether to bind to the specified interface.
521 * What Makes Good usb_device_id Tables:
523 * The match algorithm is very simple, so that intelligence in
524 * driver selection must come from smart driver id records.
525 * Unless you have good reasons to use another selection policy,
526 * provide match elements only in related groups, and order match
527 * specifiers from specific to general. Use the macros provided
528 * for that purpose if you can.
530 * The most specific match specifiers use device descriptor
531 * data. These are commonly used with product-specific matches;
532 * the USB_DEVICE macro lets you provide vendor and product IDs,
533 * and you can also match against ranges of product revisions.
534 * These are widely used for devices with application or vendor
535 * specific bDeviceClass values.
537 * Matches based on device class/subclass/protocol specifications
538 * are slightly more general; use the USB_DEVICE_INFO macro, or
539 * its siblings. These are used with single-function devices
540 * where bDeviceClass doesn't specify that each interface has
543 * Matches based on interface class/subclass/protocol are the
544 * most general; they let drivers bind to any interface on a
545 * multiple-function device. Use the USB_INTERFACE_INFO
546 * macro, or its siblings, to match class-per-interface style
547 * devices (as recorded in bInterfaceClass).
549 * Note that an entry created by USB_INTERFACE_INFO won't match
550 * any interface if the device class is set to Vendor-Specific.
551 * This is deliberate; according to the USB spec the meanings of
552 * the interface class/subclass/protocol for these devices are also
553 * vendor-specific, and hence matching against a standard product
554 * class wouldn't work anyway. If you really want to use an
555 * interface-based match for such a device, create a match record
556 * that also specifies the vendor ID. (Unforunately there isn't a
557 * standard macro for creating records like this.)
559 * Within those groups, remember that not all combinations are
560 * meaningful. For example, don't give a product version range
561 * without vendor and product IDs; or specify a protocol without
562 * its associated class and subclass.
564 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
565 const struct usb_device_id *id)
567 /* proc_connectinfo in devio.c may call us with id == NULL. */
571 /* It is important to check that id->driver_info is nonzero,
572 since an entry that is all zeroes except for a nonzero
573 id->driver_info is the way to create an entry that
574 indicates that the driver want to examine every
575 device and interface. */
576 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
577 id->bInterfaceClass || id->driver_info; id++) {
578 if (usb_match_one_id(interface, id))
584 EXPORT_SYMBOL_GPL(usb_match_id);
586 static int usb_device_match(struct device *dev, struct device_driver *drv)
588 /* devices and interfaces are handled separately */
589 if (is_usb_device(dev)) {
591 /* interface drivers never match devices */
592 if (!is_usb_device_driver(drv))
595 /* TODO: Add real matching code */
599 struct usb_interface *intf;
600 struct usb_driver *usb_drv;
601 const struct usb_device_id *id;
603 /* device drivers never match interfaces */
604 if (is_usb_device_driver(drv))
607 intf = to_usb_interface(dev);
608 usb_drv = to_usb_driver(drv);
610 id = usb_match_id(intf, usb_drv->id_table);
614 id = usb_match_dynamic_id(intf, usb_drv);
622 #ifdef CONFIG_HOTPLUG
623 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
625 struct usb_device *usb_dev;
627 /* driver is often null here; dev_dbg() would oops */
628 pr_debug("usb %s: uevent\n", dev_name(dev));
630 if (is_usb_device(dev))
631 usb_dev = to_usb_device(dev);
633 struct usb_interface *intf = to_usb_interface(dev);
634 usb_dev = interface_to_usbdev(intf);
637 if (usb_dev->devnum < 0) {
638 pr_debug("usb %s: already deleted?\n", dev_name(dev));
642 pr_debug("usb %s: bus removed?\n", dev_name(dev));
646 #ifdef CONFIG_USB_DEVICEFS
647 /* If this is available, userspace programs can directly read
648 * all the device descriptors we don't tell them about. Or
649 * act as usermode drivers.
651 if (add_uevent_var(env, "DEVICE=/proc/bus/usb/%03d/%03d",
652 usb_dev->bus->busnum, usb_dev->devnum))
656 /* per-device configurations are common */
657 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
658 le16_to_cpu(usb_dev->descriptor.idVendor),
659 le16_to_cpu(usb_dev->descriptor.idProduct),
660 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
663 /* class-based driver binding models */
664 if (add_uevent_var(env, "TYPE=%d/%d/%d",
665 usb_dev->descriptor.bDeviceClass,
666 usb_dev->descriptor.bDeviceSubClass,
667 usb_dev->descriptor.bDeviceProtocol))
675 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
679 #endif /* CONFIG_HOTPLUG */
682 * usb_register_device_driver - register a USB device (not interface) driver
683 * @new_udriver: USB operations for the device driver
684 * @owner: module owner of this driver.
686 * Registers a USB device driver with the USB core. The list of
687 * unattached devices will be rescanned whenever a new driver is
688 * added, allowing the new driver to attach to any recognized devices.
689 * Returns a negative error code on failure and 0 on success.
691 int usb_register_device_driver(struct usb_device_driver *new_udriver,
692 struct module *owner)
699 new_udriver->drvwrap.for_devices = 1;
700 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
701 new_udriver->drvwrap.driver.bus = &usb_bus_type;
702 new_udriver->drvwrap.driver.probe = usb_probe_device;
703 new_udriver->drvwrap.driver.remove = usb_unbind_device;
704 new_udriver->drvwrap.driver.owner = owner;
706 retval = driver_register(&new_udriver->drvwrap.driver);
709 pr_info("%s: registered new device driver %s\n",
710 usbcore_name, new_udriver->name);
711 usbfs_update_special();
713 printk(KERN_ERR "%s: error %d registering device "
715 usbcore_name, retval, new_udriver->name);
720 EXPORT_SYMBOL_GPL(usb_register_device_driver);
723 * usb_deregister_device_driver - unregister a USB device (not interface) driver
724 * @udriver: USB operations of the device driver to unregister
725 * Context: must be able to sleep
727 * Unlinks the specified driver from the internal USB driver list.
729 void usb_deregister_device_driver(struct usb_device_driver *udriver)
731 pr_info("%s: deregistering device driver %s\n",
732 usbcore_name, udriver->name);
734 driver_unregister(&udriver->drvwrap.driver);
735 usbfs_update_special();
737 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
740 * usb_register_driver - register a USB interface driver
741 * @new_driver: USB operations for the interface driver
742 * @owner: module owner of this driver.
743 * @mod_name: module name string
745 * Registers a USB interface driver with the USB core. The list of
746 * unattached interfaces will be rescanned whenever a new driver is
747 * added, allowing the new driver to attach to any recognized interfaces.
748 * Returns a negative error code on failure and 0 on success.
750 * NOTE: if you want your driver to use the USB major number, you must call
751 * usb_register_dev() to enable that functionality. This function no longer
752 * takes care of that.
754 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
755 const char *mod_name)
762 new_driver->drvwrap.for_devices = 0;
763 new_driver->drvwrap.driver.name = (char *) new_driver->name;
764 new_driver->drvwrap.driver.bus = &usb_bus_type;
765 new_driver->drvwrap.driver.probe = usb_probe_interface;
766 new_driver->drvwrap.driver.remove = usb_unbind_interface;
767 new_driver->drvwrap.driver.owner = owner;
768 new_driver->drvwrap.driver.mod_name = mod_name;
769 spin_lock_init(&new_driver->dynids.lock);
770 INIT_LIST_HEAD(&new_driver->dynids.list);
772 retval = driver_register(&new_driver->drvwrap.driver);
775 pr_info("%s: registered new interface driver %s\n",
776 usbcore_name, new_driver->name);
777 usbfs_update_special();
778 usb_create_newid_file(new_driver);
780 printk(KERN_ERR "%s: error %d registering interface "
782 usbcore_name, retval, new_driver->name);
787 EXPORT_SYMBOL_GPL(usb_register_driver);
790 * usb_deregister - unregister a USB interface driver
791 * @driver: USB operations of the interface driver to unregister
792 * Context: must be able to sleep
794 * Unlinks the specified driver from the internal USB driver list.
796 * NOTE: If you called usb_register_dev(), you still need to call
797 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
798 * this * call will no longer do it for you.
800 void usb_deregister(struct usb_driver *driver)
802 pr_info("%s: deregistering interface driver %s\n",
803 usbcore_name, driver->name);
805 usb_remove_newid_file(driver);
806 usb_free_dynids(driver);
807 driver_unregister(&driver->drvwrap.driver);
809 usbfs_update_special();
811 EXPORT_SYMBOL_GPL(usb_deregister);
813 /* Forced unbinding of a USB interface driver, either because
814 * it doesn't support pre_reset/post_reset/reset_resume or
815 * because it doesn't support suspend/resume.
817 * The caller must hold @intf's device's lock, but not its pm_mutex
818 * and not @intf->dev.sem.
820 void usb_forced_unbind_intf(struct usb_interface *intf)
822 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
824 dev_dbg(&intf->dev, "forced unbind\n");
825 usb_driver_release_interface(driver, intf);
827 /* Mark the interface for later rebinding */
828 intf->needs_binding = 1;
831 /* Delayed forced unbinding of a USB interface driver and scan
834 * The caller must hold @intf's device's lock, but not its pm_mutex
835 * and not @intf->dev.sem.
837 * Note: Rebinds will be skipped if a system sleep transition is in
838 * progress and the PM "complete" callback hasn't occurred yet.
840 void usb_rebind_intf(struct usb_interface *intf)
844 /* Delayed unbind of an existing driver */
845 if (intf->dev.driver) {
846 struct usb_driver *driver =
847 to_usb_driver(intf->dev.driver);
849 dev_dbg(&intf->dev, "forced unbind\n");
850 usb_driver_release_interface(driver, intf);
853 /* Try to rebind the interface */
854 if (intf->dev.power.status == DPM_ON) {
855 intf->needs_binding = 0;
856 rc = device_attach(&intf->dev);
858 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
867 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
868 * or rebind interfaces that have been unbound, according to @action.
870 * The caller must hold @udev's device lock.
872 static void do_unbind_rebind(struct usb_device *udev, int action)
874 struct usb_host_config *config;
876 struct usb_interface *intf;
877 struct usb_driver *drv;
879 config = udev->actconfig;
881 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
882 intf = config->interface[i];
885 if (intf->dev.driver) {
886 drv = to_usb_driver(intf->dev.driver);
887 if (!drv->suspend || !drv->resume)
888 usb_forced_unbind_intf(intf);
892 if (intf->needs_binding)
893 usb_rebind_intf(intf);
900 /* Caller has locked udev's pm_mutex */
901 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
903 struct usb_device_driver *udriver;
906 if (udev->state == USB_STATE_NOTATTACHED ||
907 udev->state == USB_STATE_SUSPENDED)
910 /* For devices that don't have a driver, we do a generic suspend. */
911 if (udev->dev.driver)
912 udriver = to_usb_device_driver(udev->dev.driver);
914 udev->do_remote_wakeup = 0;
915 udriver = &usb_generic_driver;
917 status = udriver->suspend(udev, msg);
920 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
924 /* Caller has locked udev's pm_mutex */
925 static int usb_resume_device(struct usb_device *udev)
927 struct usb_device_driver *udriver;
930 if (udev->state == USB_STATE_NOTATTACHED)
933 /* Can't resume it if it doesn't have a driver. */
934 if (udev->dev.driver == NULL) {
939 if (udev->quirks & USB_QUIRK_RESET_RESUME)
940 udev->reset_resume = 1;
942 udriver = to_usb_device_driver(udev->dev.driver);
943 status = udriver->resume(udev);
946 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
948 udev->autoresume_disabled = 0;
952 /* Caller has locked intf's usb_device's pm mutex */
953 static int usb_suspend_interface(struct usb_device *udev,
954 struct usb_interface *intf, pm_message_t msg)
956 struct usb_driver *driver;
959 /* with no hardware, USB interfaces only use FREEZE and ON states */
960 if (udev->state == USB_STATE_NOTATTACHED || !is_active(intf))
963 /* This can happen; see usb_driver_release_interface() */
964 if (intf->condition == USB_INTERFACE_UNBOUND)
966 driver = to_usb_driver(intf->dev.driver);
968 if (driver->suspend) {
969 status = driver->suspend(intf, msg);
972 else if (!udev->auto_pm)
973 dev_err(&intf->dev, "%s error %d\n",
976 /* Later we will unbind the driver and reprobe */
977 intf->needs_binding = 1;
978 dev_warn(&intf->dev, "no %s for driver %s?\n",
979 "suspend", driver->name);
984 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
988 /* Caller has locked intf's usb_device's pm_mutex */
989 static int usb_resume_interface(struct usb_device *udev,
990 struct usb_interface *intf, int reset_resume)
992 struct usb_driver *driver;
995 if (udev->state == USB_STATE_NOTATTACHED || is_active(intf))
998 /* Don't let autoresume interfere with unbinding */
999 if (intf->condition == USB_INTERFACE_UNBINDING)
1002 /* Can't resume it if it doesn't have a driver. */
1003 if (intf->condition == USB_INTERFACE_UNBOUND) {
1005 /* Carry out a deferred switch to altsetting 0 */
1006 if (intf->needs_altsetting0 &&
1007 intf->dev.power.status == DPM_ON) {
1008 usb_set_interface(udev, intf->altsetting[0].
1009 desc.bInterfaceNumber, 0);
1010 intf->needs_altsetting0 = 0;
1015 /* Don't resume if the interface is marked for rebinding */
1016 if (intf->needs_binding)
1018 driver = to_usb_driver(intf->dev.driver);
1021 if (driver->reset_resume) {
1022 status = driver->reset_resume(intf);
1024 dev_err(&intf->dev, "%s error %d\n",
1025 "reset_resume", status);
1027 intf->needs_binding = 1;
1028 dev_warn(&intf->dev, "no %s for driver %s?\n",
1029 "reset_resume", driver->name);
1032 if (driver->resume) {
1033 status = driver->resume(intf);
1035 dev_err(&intf->dev, "%s error %d\n",
1038 intf->needs_binding = 1;
1039 dev_warn(&intf->dev, "no %s for driver %s?\n",
1040 "resume", driver->name);
1045 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1046 if (status == 0 && intf->condition == USB_INTERFACE_BOUND)
1049 /* Later we will unbind the driver and/or reprobe, if necessary */
1053 #ifdef CONFIG_USB_SUSPEND
1055 /* Internal routine to check whether we may autosuspend a device. */
1056 static int autosuspend_check(struct usb_device *udev, int reschedule)
1059 struct usb_interface *intf;
1060 unsigned long suspend_time, j;
1062 /* For autosuspend, fail fast if anything is in use or autosuspend
1063 * is disabled. Also fail if any interfaces require remote wakeup
1064 * but it isn't available.
1066 if (udev->pm_usage_cnt > 0)
1068 if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
1071 suspend_time = udev->last_busy + udev->autosuspend_delay;
1072 if (udev->actconfig) {
1073 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1074 intf = udev->actconfig->interface[i];
1075 if (!is_active(intf))
1077 if (intf->pm_usage_cnt > 0)
1079 if (intf->needs_remote_wakeup &&
1080 !udev->do_remote_wakeup) {
1081 dev_dbg(&udev->dev, "remote wakeup needed "
1082 "for autosuspend\n");
1086 /* Don't allow autosuspend if the device will need
1087 * a reset-resume and any of its interface drivers
1088 * doesn't include support.
1090 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1091 struct usb_driver *driver;
1093 driver = to_usb_driver(intf->dev.driver);
1094 if (!driver->reset_resume ||
1095 intf->needs_remote_wakeup)
1101 /* If everything is okay but the device hasn't been idle for long
1102 * enough, queue a delayed autosuspend request. If the device
1103 * _has_ been idle for long enough and the reschedule flag is set,
1104 * likewise queue a delayed (1 second) autosuspend request.
1107 if (time_before(j, suspend_time))
1110 suspend_time = j + HZ;
1112 if (!timer_pending(&udev->autosuspend.timer)) {
1113 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
1114 round_jiffies_up_relative(suspend_time - j));
1123 static inline int autosuspend_check(struct usb_device *udev, int reschedule)
1128 #endif /* CONFIG_USB_SUSPEND */
1131 * usb_suspend_both - suspend a USB device and its interfaces
1132 * @udev: the usb_device to suspend
1133 * @msg: Power Management message describing this state transition
1135 * This is the central routine for suspending USB devices. It calls the
1136 * suspend methods for all the interface drivers in @udev and then calls
1137 * the suspend method for @udev itself. If an error occurs at any stage,
1138 * all the interfaces which were suspended are resumed so that they remain
1139 * in the same state as the device.
1141 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
1142 * checks first to make sure that neither the device itself or any of its
1143 * active interfaces is in use (pm_usage_cnt is greater than 0). If they
1144 * are, the autosuspend fails.
1146 * If the suspend succeeds, the routine recursively queues an autosuspend
1147 * request for @udev's parent device, thereby propagating the change up
1148 * the device tree. If all of the parent's children are now suspended,
1149 * the parent will autosuspend in turn.
1151 * The suspend method calls are subject to mutual exclusion under control
1152 * of @udev's pm_mutex. Many of these calls are also under the protection
1153 * of @udev's device lock (including all requests originating outside the
1154 * USB subsystem), but autosuspend requests generated by a child device or
1155 * interface driver may not be. Usbcore will insure that the method calls
1156 * do not arrive during bind, unbind, or reset operations. However, drivers
1157 * must be prepared to handle suspend calls arriving at unpredictable times.
1158 * The only way to block such calls is to do an autoresume (preventing
1159 * autosuspends) while holding @udev's device lock (preventing outside
1162 * The caller must hold @udev->pm_mutex.
1164 * This routine can run only in process context.
1166 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1170 struct usb_interface *intf;
1171 struct usb_device *parent = udev->parent;
1173 if (udev->state == USB_STATE_NOTATTACHED ||
1174 udev->state == USB_STATE_SUSPENDED)
1177 udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
1179 if (udev->auto_pm) {
1180 status = autosuspend_check(udev, 0);
1185 /* Suspend all the interfaces and then udev itself */
1186 if (udev->actconfig) {
1187 for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
1188 intf = udev->actconfig->interface[i];
1189 status = usb_suspend_interface(udev, intf, msg);
1195 status = usb_suspend_device(udev, msg);
1197 /* If the suspend failed, resume interfaces that did get suspended */
1200 intf = udev->actconfig->interface[i];
1201 usb_resume_interface(udev, intf, 0);
1204 /* Try another autosuspend when the interfaces aren't busy */
1206 autosuspend_check(udev, status == -EBUSY);
1208 /* If the suspend succeeded then prevent any more URB submissions,
1209 * flush any outstanding URBs, and propagate the suspend up the tree.
1212 cancel_delayed_work(&udev->autosuspend);
1213 udev->can_submit = 0;
1214 for (i = 0; i < 16; ++i) {
1215 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1216 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1219 /* If this is just a FREEZE or a PRETHAW, udev might
1220 * not really be suspended. Only true suspends get
1221 * propagated up the device tree.
1223 if (parent && udev->state == USB_STATE_SUSPENDED)
1224 usb_autosuspend_device(parent);
1228 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1233 * usb_resume_both - resume a USB device and its interfaces
1234 * @udev: the usb_device to resume
1236 * This is the central routine for resuming USB devices. It calls the
1237 * the resume method for @udev and then calls the resume methods for all
1238 * the interface drivers in @udev.
1240 * Before starting the resume, the routine calls itself recursively for
1241 * the parent device of @udev, thereby propagating the change up the device
1242 * tree and assuring that @udev will be able to resume. If the parent is
1243 * unable to resume successfully, the routine fails.
1245 * The resume method calls are subject to mutual exclusion under control
1246 * of @udev's pm_mutex. Many of these calls are also under the protection
1247 * of @udev's device lock (including all requests originating outside the
1248 * USB subsystem), but autoresume requests generated by a child device or
1249 * interface driver may not be. Usbcore will insure that the method calls
1250 * do not arrive during bind, unbind, or reset operations. However, drivers
1251 * must be prepared to handle resume calls arriving at unpredictable times.
1252 * The only way to block such calls is to do an autoresume (preventing
1253 * other autoresumes) while holding @udev's device lock (preventing outside
1256 * The caller must hold @udev->pm_mutex.
1258 * This routine can run only in process context.
1260 static int usb_resume_both(struct usb_device *udev)
1264 struct usb_interface *intf;
1265 struct usb_device *parent = udev->parent;
1267 cancel_delayed_work(&udev->autosuspend);
1268 if (udev->state == USB_STATE_NOTATTACHED) {
1272 udev->can_submit = 1;
1274 /* Propagate the resume up the tree, if necessary */
1275 if (udev->state == USB_STATE_SUSPENDED) {
1276 if (udev->auto_pm && udev->autoresume_disabled) {
1281 status = usb_autoresume_device(parent);
1283 status = usb_resume_device(udev);
1284 if (status || udev->state ==
1285 USB_STATE_NOTATTACHED) {
1286 usb_autosuspend_device(parent);
1288 /* It's possible usb_resume_device()
1289 * failed after the port was
1290 * unsuspended, causing udev to be
1291 * logically disconnected. We don't
1292 * want usb_disconnect() to autosuspend
1293 * the parent again, so tell it that
1294 * udev disconnected while still
1297 USB_STATE_NOTATTACHED)
1298 udev->discon_suspended = 1;
1303 /* We can't progagate beyond the USB subsystem,
1304 * so if a root hub's controller is suspended
1305 * then we're stuck. */
1306 status = usb_resume_device(udev);
1308 } else if (udev->reset_resume)
1309 status = usb_resume_device(udev);
1311 if (status == 0 && udev->actconfig) {
1312 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1313 intf = udev->actconfig->interface[i];
1314 usb_resume_interface(udev, intf, udev->reset_resume);
1319 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1321 udev->reset_resume = 0;
1325 #ifdef CONFIG_USB_SUSPEND
1327 /* Internal routine to adjust a device's usage counter and change
1328 * its autosuspend state.
1330 static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
1336 udev->pm_usage_cnt += inc_usage_cnt;
1337 WARN_ON(udev->pm_usage_cnt < 0);
1339 udev->last_busy = jiffies;
1340 if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
1341 if (udev->state == USB_STATE_SUSPENDED)
1342 status = usb_resume_both(udev);
1344 udev->pm_usage_cnt -= inc_usage_cnt;
1345 else if (inc_usage_cnt)
1346 udev->last_busy = jiffies;
1347 } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
1348 status = usb_suspend_both(udev, PMSG_SUSPEND);
1350 usb_pm_unlock(udev);
1354 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1355 void usb_autosuspend_work(struct work_struct *work)
1357 struct usb_device *udev =
1358 container_of(work, struct usb_device, autosuspend.work);
1360 usb_autopm_do_device(udev, 0);
1363 /* usb_autoresume_work - callback routine to autoresume a USB device */
1364 void usb_autoresume_work(struct work_struct *work)
1366 struct usb_device *udev =
1367 container_of(work, struct usb_device, autoresume);
1369 /* Wake it up, let the drivers do their thing, and then put it
1372 if (usb_autopm_do_device(udev, 1) == 0)
1373 usb_autopm_do_device(udev, -1);
1377 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1378 * @udev: the usb_device to autosuspend
1380 * This routine should be called when a core subsystem is finished using
1381 * @udev and wants to allow it to autosuspend. Examples would be when
1382 * @udev's device file in usbfs is closed or after a configuration change.
1384 * @udev's usage counter is decremented. If it or any of the usage counters
1385 * for an active interface is greater than 0, no autosuspend request will be
1386 * queued. (If an interface driver does not support autosuspend then its
1387 * usage counter is permanently positive.) Furthermore, if an interface
1388 * driver requires remote-wakeup capability during autosuspend but remote
1389 * wakeup is disabled, the autosuspend will fail.
1391 * Often the caller will hold @udev's device lock, but this is not
1394 * This routine can run only in process context.
1396 void usb_autosuspend_device(struct usb_device *udev)
1400 status = usb_autopm_do_device(udev, -1);
1401 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1402 __func__, udev->pm_usage_cnt);
1406 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1407 * @udev: the usb_device to autosuspend
1409 * This routine should be called when a core subsystem thinks @udev may
1410 * be ready to autosuspend.
1412 * @udev's usage counter left unchanged. If it or any of the usage counters
1413 * for an active interface is greater than 0, or autosuspend is not allowed
1414 * for any other reason, no autosuspend request will be queued.
1416 * This routine can run only in process context.
1418 void usb_try_autosuspend_device(struct usb_device *udev)
1420 usb_autopm_do_device(udev, 0);
1421 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1422 __func__, udev->pm_usage_cnt);
1426 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1427 * @udev: the usb_device to autoresume
1429 * This routine should be called when a core subsystem wants to use @udev
1430 * and needs to guarantee that it is not suspended. No autosuspend will
1431 * occur until usb_autosuspend_device is called. (Note that this will not
1432 * prevent suspend events originating in the PM core.) Examples would be
1433 * when @udev's device file in usbfs is opened or when a remote-wakeup
1434 * request is received.
1436 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1437 * However if the autoresume fails then the usage counter is re-decremented.
1439 * Often the caller will hold @udev's device lock, but this is not
1440 * necessary (and attempting it might cause deadlock).
1442 * This routine can run only in process context.
1444 int usb_autoresume_device(struct usb_device *udev)
1448 status = usb_autopm_do_device(udev, 1);
1449 dev_vdbg(&udev->dev, "%s: status %d cnt %d\n",
1450 __func__, status, udev->pm_usage_cnt);
1454 /* Internal routine to adjust an interface's usage counter and change
1455 * its device's autosuspend state.
1457 static int usb_autopm_do_interface(struct usb_interface *intf,
1460 struct usb_device *udev = interface_to_usbdev(intf);
1464 if (intf->condition == USB_INTERFACE_UNBOUND)
1468 intf->pm_usage_cnt += inc_usage_cnt;
1469 udev->last_busy = jiffies;
1470 if (inc_usage_cnt >= 0 && intf->pm_usage_cnt > 0) {
1471 if (udev->state == USB_STATE_SUSPENDED)
1472 status = usb_resume_both(udev);
1474 intf->pm_usage_cnt -= inc_usage_cnt;
1476 udev->last_busy = jiffies;
1477 } else if (inc_usage_cnt <= 0 && intf->pm_usage_cnt <= 0) {
1478 status = usb_suspend_both(udev, PMSG_SUSPEND);
1481 usb_pm_unlock(udev);
1486 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1487 * @intf: the usb_interface whose counter should be decremented
1489 * This routine should be called by an interface driver when it is
1490 * finished using @intf and wants to allow it to autosuspend. A typical
1491 * example would be a character-device driver when its device file is
1494 * The routine decrements @intf's usage counter. When the counter reaches
1495 * 0, a delayed autosuspend request for @intf's device is queued. When
1496 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1497 * the other usage counters for the sibling interfaces and @intf's
1498 * usb_device, the device and all its interfaces will be autosuspended.
1500 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1501 * core will not change its value other than the increment and decrement
1502 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1503 * may use this simple counter-oriented discipline or may set the value
1506 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1507 * take place only if the device's remote-wakeup facility is enabled.
1509 * Suspend method calls queued by this routine can arrive at any time
1510 * while @intf is resumed and its usage counter is equal to 0. They are
1511 * not protected by the usb_device's lock but only by its pm_mutex.
1512 * Drivers must provide their own synchronization.
1514 * This routine can run only in process context.
1516 void usb_autopm_put_interface(struct usb_interface *intf)
1520 status = usb_autopm_do_interface(intf, -1);
1521 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1522 __func__, status, intf->pm_usage_cnt);
1524 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1527 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1528 * @intf: the usb_interface whose counter should be decremented
1530 * This routine does essentially the same thing as
1531 * usb_autopm_put_interface(): it decrements @intf's usage counter and
1532 * queues a delayed autosuspend request if the counter is <= 0. The
1533 * difference is that it does not acquire the device's pm_mutex;
1534 * callers must handle all synchronization issues themselves.
1536 * Typically a driver would call this routine during an URB's completion
1537 * handler, if no more URBs were pending.
1539 * This routine can run in atomic context.
1541 void usb_autopm_put_interface_async(struct usb_interface *intf)
1543 struct usb_device *udev = interface_to_usbdev(intf);
1546 if (intf->condition == USB_INTERFACE_UNBOUND) {
1549 udev->last_busy = jiffies;
1550 --intf->pm_usage_cnt;
1551 if (udev->autosuspend_disabled || udev->autosuspend_delay < 0)
1553 else if (intf->pm_usage_cnt <= 0 &&
1554 !timer_pending(&udev->autosuspend.timer)) {
1555 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
1556 round_jiffies_up_relative(
1557 udev->autosuspend_delay));
1560 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1561 __func__, status, intf->pm_usage_cnt);
1563 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1566 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1567 * @intf: the usb_interface whose counter should be incremented
1569 * This routine should be called by an interface driver when it wants to
1570 * use @intf and needs to guarantee that it is not suspended. In addition,
1571 * the routine prevents @intf from being autosuspended subsequently. (Note
1572 * that this will not prevent suspend events originating in the PM core.)
1573 * This prevention will persist until usb_autopm_put_interface() is called
1574 * or @intf is unbound. A typical example would be a character-device
1575 * driver when its device file is opened.
1578 * The routine increments @intf's usage counter. (However if the
1579 * autoresume fails then the counter is re-decremented.) So long as the
1580 * counter is greater than 0, autosuspend will not be allowed for @intf
1581 * or its usb_device. When the driver is finished using @intf it should
1582 * call usb_autopm_put_interface() to decrement the usage counter and
1583 * queue a delayed autosuspend request (if the counter is <= 0).
1586 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1587 * core will not change its value other than the increment and decrement
1588 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1589 * may use this simple counter-oriented discipline or may set the value
1592 * Resume method calls generated by this routine can arrive at any time
1593 * while @intf is suspended. They are not protected by the usb_device's
1594 * lock but only by its pm_mutex. Drivers must provide their own
1597 * This routine can run only in process context.
1599 int usb_autopm_get_interface(struct usb_interface *intf)
1603 status = usb_autopm_do_interface(intf, 1);
1604 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1605 __func__, status, intf->pm_usage_cnt);
1608 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1611 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1612 * @intf: the usb_interface whose counter should be incremented
1614 * This routine does much the same thing as
1615 * usb_autopm_get_interface(): it increments @intf's usage counter and
1616 * queues an autoresume request if the result is > 0. The differences
1617 * are that it does not acquire the device's pm_mutex (callers must
1618 * handle all synchronization issues themselves), and it does not
1619 * autoresume the device directly (it only queues a request). After a
1620 * successful call, the device will generally not yet be resumed.
1622 * This routine can run in atomic context.
1624 int usb_autopm_get_interface_async(struct usb_interface *intf)
1626 struct usb_device *udev = interface_to_usbdev(intf);
1629 if (intf->condition == USB_INTERFACE_UNBOUND)
1631 else if (udev->autoresume_disabled)
1633 else if (++intf->pm_usage_cnt > 0 && udev->state == USB_STATE_SUSPENDED)
1634 queue_work(ksuspend_usb_wq, &udev->autoresume);
1635 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1636 __func__, status, intf->pm_usage_cnt);
1639 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1642 * usb_autopm_set_interface - set a USB interface's autosuspend state
1643 * @intf: the usb_interface whose state should be set
1645 * This routine sets the autosuspend state of @intf's device according
1646 * to @intf's usage counter, which the caller must have set previously.
1647 * If the counter is <= 0, the device is autosuspended (if it isn't
1648 * already suspended and if nothing else prevents the autosuspend). If
1649 * the counter is > 0, the device is autoresumed (if it isn't already
1652 int usb_autopm_set_interface(struct usb_interface *intf)
1656 status = usb_autopm_do_interface(intf, 0);
1657 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1658 __func__, status, intf->pm_usage_cnt);
1661 EXPORT_SYMBOL_GPL(usb_autopm_set_interface);
1665 void usb_autosuspend_work(struct work_struct *work)
1668 void usb_autoresume_work(struct work_struct *work)
1671 #endif /* CONFIG_USB_SUSPEND */
1674 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1675 * @udev: the usb_device to suspend
1676 * @msg: Power Management message describing this state transition
1678 * This routine handles external suspend requests: ones not generated
1679 * internally by a USB driver (autosuspend) but rather coming from the user
1680 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1681 * out regardless of @udev's usage counter or those of its interfaces,
1682 * and regardless of whether or not remote wakeup is enabled. Of course,
1683 * interface drivers still have the option of failing the suspend (if
1684 * there are unsuspended children, for example).
1686 * The caller must hold @udev's device lock.
1688 int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
1692 do_unbind_rebind(udev, DO_UNBIND);
1695 status = usb_suspend_both(udev, msg);
1696 usb_pm_unlock(udev);
1701 * usb_external_resume_device - external resume of a USB device and its interfaces
1702 * @udev: the usb_device to resume
1704 * This routine handles external resume requests: ones not generated
1705 * internally by a USB driver (autoresume) but rather coming from the user
1706 * (via sysfs), the PM core (system resume), or the device itself (remote
1707 * wakeup). @udev's usage counter is unaffected.
1709 * The caller must hold @udev's device lock.
1711 int usb_external_resume_device(struct usb_device *udev)
1717 status = usb_resume_both(udev);
1718 udev->last_busy = jiffies;
1719 usb_pm_unlock(udev);
1721 do_unbind_rebind(udev, DO_REBIND);
1723 /* Now that the device is awake, we can start trying to autosuspend
1726 usb_try_autosuspend_device(udev);
1730 int usb_suspend(struct device *dev, pm_message_t message)
1732 struct usb_device *udev;
1734 udev = to_usb_device(dev);
1736 /* If udev is already suspended, we can skip this suspend and
1737 * we should also skip the upcoming system resume. High-speed
1738 * root hubs are an exception; they need to resume whenever the
1739 * system wakes up in order for USB-PERSIST port handover to work
1742 if (udev->state == USB_STATE_SUSPENDED) {
1743 if (udev->parent || udev->speed != USB_SPEED_HIGH)
1744 udev->skip_sys_resume = 1;
1748 udev->skip_sys_resume = 0;
1749 return usb_external_suspend_device(udev, message);
1752 int usb_resume(struct device *dev)
1754 struct usb_device *udev;
1756 udev = to_usb_device(dev);
1758 /* If udev->skip_sys_resume is set then udev was already suspended
1759 * when the system sleep started, so we don't want to resume it
1760 * during this system wakeup.
1762 if (udev->skip_sys_resume)
1764 return usb_external_resume_device(udev);
1767 #endif /* CONFIG_PM */
1769 struct bus_type usb_bus_type = {
1771 .match = usb_device_match,
1772 .uevent = usb_uevent,