2 * drivers/usb/driver.c - most of the driver model stuff for usb
4 * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
6 * based on drivers/usb/usb.c which had the following copyrights:
7 * (C) Copyright Linus Torvalds 1999
8 * (C) Copyright Johannes Erdfelt 1999-2001
9 * (C) Copyright Andreas Gal 1999
10 * (C) Copyright Gregory P. Smith 1999
11 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
12 * (C) Copyright Randy Dunlap 2000
13 * (C) Copyright David Brownell 2000-2004
14 * (C) Copyright Yggdrasil Computing, Inc. 2000
15 * (usb_device_id matching changes by Adam J. Richter)
16 * (C) Copyright Greg Kroah-Hartman 2002-2003
18 * NOTE! This is not actually a driver at all, rather this is
19 * just a collection of helper routines that implement the
20 * matching, probing, releasing, suspending and resuming for
25 #include <linux/device.h>
26 #include <linux/usb.h>
27 #include <linux/usb/quirks.h>
28 #include <linux/workqueue.h>
36 * Adds a new dynamic USBdevice ID to this driver,
37 * and cause the driver to probe for all devices again.
39 ssize_t usb_store_new_id(struct usb_dynids *dynids,
40 struct device_driver *driver,
41 const char *buf, size_t count)
43 struct usb_dynid *dynid;
49 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
53 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
57 INIT_LIST_HEAD(&dynid->node);
58 dynid->id.idVendor = idVendor;
59 dynid->id.idProduct = idProduct;
60 dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
62 spin_lock(&dynids->lock);
63 list_add_tail(&dynid->node, &dynids->list);
64 spin_unlock(&dynids->lock);
66 if (get_driver(driver)) {
67 retval = driver_attach(driver);
75 EXPORT_SYMBOL_GPL(usb_store_new_id);
77 static ssize_t store_new_id(struct device_driver *driver,
78 const char *buf, size_t count)
80 struct usb_driver *usb_drv = to_usb_driver(driver);
82 return usb_store_new_id(&usb_drv->dynids, driver, buf, count);
84 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
86 static int usb_create_newid_file(struct usb_driver *usb_drv)
90 if (usb_drv->no_dynamic_id)
93 if (usb_drv->probe != NULL)
94 error = driver_create_file(&usb_drv->drvwrap.driver,
100 static void usb_remove_newid_file(struct usb_driver *usb_drv)
102 if (usb_drv->no_dynamic_id)
105 if (usb_drv->probe != NULL)
106 driver_remove_file(&usb_drv->drvwrap.driver,
107 &driver_attr_new_id);
110 static void usb_free_dynids(struct usb_driver *usb_drv)
112 struct usb_dynid *dynid, *n;
114 spin_lock(&usb_drv->dynids.lock);
115 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
116 list_del(&dynid->node);
119 spin_unlock(&usb_drv->dynids.lock);
122 static inline int usb_create_newid_file(struct usb_driver *usb_drv)
127 static void usb_remove_newid_file(struct usb_driver *usb_drv)
131 static inline void usb_free_dynids(struct usb_driver *usb_drv)
136 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
137 struct usb_driver *drv)
139 struct usb_dynid *dynid;
141 spin_lock(&drv->dynids.lock);
142 list_for_each_entry(dynid, &drv->dynids.list, node) {
143 if (usb_match_one_id(intf, &dynid->id)) {
144 spin_unlock(&drv->dynids.lock);
148 spin_unlock(&drv->dynids.lock);
153 /* called from driver core with dev locked */
154 static int usb_probe_device(struct device *dev)
156 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
157 struct usb_device *udev;
160 dev_dbg(dev, "%s\n", __func__);
162 if (!is_usb_device(dev)) /* Sanity check */
165 udev = to_usb_device(dev);
167 /* TODO: Add real matching code */
169 /* The device should always appear to be in use
170 * unless the driver suports autosuspend.
172 udev->pm_usage_cnt = !(udriver->supports_autosuspend);
174 error = udriver->probe(udev);
178 /* called from driver core with dev locked */
179 static int usb_unbind_device(struct device *dev)
181 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
183 udriver->disconnect(to_usb_device(dev));
188 /* called from driver core with dev locked */
189 static int usb_probe_interface(struct device *dev)
191 struct usb_driver *driver = to_usb_driver(dev->driver);
192 struct usb_interface *intf;
193 struct usb_device *udev;
194 const struct usb_device_id *id;
197 dev_dbg(dev, "%s\n", __func__);
199 if (is_usb_device(dev)) /* Sanity check */
202 intf = to_usb_interface(dev);
203 udev = interface_to_usbdev(intf);
205 if (udev->authorized == 0) {
206 dev_err(&intf->dev, "Device is not authorized for usage\n");
210 id = usb_match_id(intf, driver->id_table);
212 id = usb_match_dynamic_id(intf, driver);
214 dev_dbg(dev, "%s - got id\n", __func__);
216 error = usb_autoresume_device(udev);
220 /* Interface "power state" doesn't correspond to any hardware
221 * state whatsoever. We use it to record when it's bound to
222 * a driver that may start I/0: it's not frozen/quiesced.
225 intf->condition = USB_INTERFACE_BINDING;
227 /* The interface should always appear to be in use
228 * unless the driver suports autosuspend.
230 intf->pm_usage_cnt = !(driver->supports_autosuspend);
232 error = driver->probe(intf, id);
235 intf->needs_remote_wakeup = 0;
236 intf->condition = USB_INTERFACE_UNBOUND;
238 intf->condition = USB_INTERFACE_BOUND;
240 usb_autosuspend_device(udev);
246 /* called from driver core with dev locked */
247 static int usb_unbind_interface(struct device *dev)
249 struct usb_driver *driver = to_usb_driver(dev->driver);
250 struct usb_interface *intf = to_usb_interface(dev);
251 struct usb_device *udev;
254 intf->condition = USB_INTERFACE_UNBINDING;
256 /* Autoresume for set_interface call below */
257 udev = interface_to_usbdev(intf);
258 error = usb_autoresume_device(udev);
260 /* Terminate all URBs for this interface unless the driver
261 * supports "soft" unbinding.
263 if (!driver->soft_unbind)
264 usb_disable_interface(udev, intf);
266 driver->disconnect(intf);
268 /* reset other interface state */
269 usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
270 usb_set_intfdata(intf, NULL);
272 intf->condition = USB_INTERFACE_UNBOUND;
274 intf->needs_remote_wakeup = 0;
277 usb_autosuspend_device(udev);
283 * usb_driver_claim_interface - bind a driver to an interface
284 * @driver: the driver to be bound
285 * @iface: the interface to which it will be bound; must be in the
286 * usb device's active configuration
287 * @priv: driver data associated with that interface
289 * This is used by usb device drivers that need to claim more than one
290 * interface on a device when probing (audio and acm are current examples).
291 * No device driver should directly modify internal usb_interface or
292 * usb_device structure members.
294 * Few drivers should need to use this routine, since the most natural
295 * way to bind to an interface is to return the private data from
296 * the driver's probe() method.
298 * Callers must own the device lock, so driver probe() entries don't need
299 * extra locking, but other call contexts may need to explicitly claim that
302 int usb_driver_claim_interface(struct usb_driver *driver,
303 struct usb_interface *iface, void *priv)
305 struct device *dev = &iface->dev;
306 struct usb_device *udev = interface_to_usbdev(iface);
312 dev->driver = &driver->drvwrap.driver;
313 usb_set_intfdata(iface, priv);
316 iface->condition = USB_INTERFACE_BOUND;
318 iface->pm_usage_cnt = !(driver->supports_autosuspend);
321 /* if interface was already added, bind now; else let
322 * the future device_add() bind it, bypassing probe()
324 if (device_is_registered(dev))
325 retval = device_bind_driver(dev);
329 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
332 * usb_driver_release_interface - unbind a driver from an interface
333 * @driver: the driver to be unbound
334 * @iface: the interface from which it will be unbound
336 * This can be used by drivers to release an interface without waiting
337 * for their disconnect() methods to be called. In typical cases this
338 * also causes the driver disconnect() method to be called.
340 * This call is synchronous, and may not be used in an interrupt context.
341 * Callers must own the device lock, so driver disconnect() entries don't
342 * need extra locking, but other call contexts may need to explicitly claim
345 void usb_driver_release_interface(struct usb_driver *driver,
346 struct usb_interface *iface)
348 struct device *dev = &iface->dev;
349 struct usb_device *udev = interface_to_usbdev(iface);
351 /* this should never happen, don't release something that's not ours */
352 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
355 /* don't release from within disconnect() */
356 if (iface->condition != USB_INTERFACE_BOUND)
359 /* don't release if the interface hasn't been added yet */
360 if (device_is_registered(dev)) {
361 iface->condition = USB_INTERFACE_UNBINDING;
362 device_release_driver(dev);
366 usb_set_intfdata(iface, NULL);
369 iface->condition = USB_INTERFACE_UNBOUND;
370 mark_quiesced(iface);
371 iface->needs_remote_wakeup = 0;
374 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
376 /* returns 0 if no match, 1 if match */
377 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
379 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
380 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
383 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
384 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
387 /* No need to test id->bcdDevice_lo != 0, since 0 is never
388 greater than any unsigned number. */
389 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
390 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
393 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
394 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
397 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
398 (id->bDeviceClass != dev->descriptor.bDeviceClass))
401 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
402 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
405 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
406 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
412 /* returns 0 if no match, 1 if match */
413 int usb_match_one_id(struct usb_interface *interface,
414 const struct usb_device_id *id)
416 struct usb_host_interface *intf;
417 struct usb_device *dev;
419 /* proc_connectinfo in devio.c may call us with id == NULL. */
423 intf = interface->cur_altsetting;
424 dev = interface_to_usbdev(interface);
426 if (!usb_match_device(dev, id))
429 /* The interface class, subclass, and protocol should never be
430 * checked for a match if the device class is Vendor Specific,
431 * unless the match record specifies the Vendor ID. */
432 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
433 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
434 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
435 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
436 USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
439 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
440 (id->bInterfaceClass != intf->desc.bInterfaceClass))
443 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
444 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
447 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
448 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
453 EXPORT_SYMBOL_GPL(usb_match_one_id);
456 * usb_match_id - find first usb_device_id matching device or interface
457 * @interface: the interface of interest
458 * @id: array of usb_device_id structures, terminated by zero entry
460 * usb_match_id searches an array of usb_device_id's and returns
461 * the first one matching the device or interface, or null.
462 * This is used when binding (or rebinding) a driver to an interface.
463 * Most USB device drivers will use this indirectly, through the usb core,
464 * but some layered driver frameworks use it directly.
465 * These device tables are exported with MODULE_DEVICE_TABLE, through
466 * modutils, to support the driver loading functionality of USB hotplugging.
470 * The "match_flags" element in a usb_device_id controls which
471 * members are used. If the corresponding bit is set, the
472 * value in the device_id must match its corresponding member
473 * in the device or interface descriptor, or else the device_id
476 * "driver_info" is normally used only by device drivers,
477 * but you can create a wildcard "matches anything" usb_device_id
478 * as a driver's "modules.usbmap" entry if you provide an id with
479 * only a nonzero "driver_info" field. If you do this, the USB device
480 * driver's probe() routine should use additional intelligence to
481 * decide whether to bind to the specified interface.
483 * What Makes Good usb_device_id Tables:
485 * The match algorithm is very simple, so that intelligence in
486 * driver selection must come from smart driver id records.
487 * Unless you have good reasons to use another selection policy,
488 * provide match elements only in related groups, and order match
489 * specifiers from specific to general. Use the macros provided
490 * for that purpose if you can.
492 * The most specific match specifiers use device descriptor
493 * data. These are commonly used with product-specific matches;
494 * the USB_DEVICE macro lets you provide vendor and product IDs,
495 * and you can also match against ranges of product revisions.
496 * These are widely used for devices with application or vendor
497 * specific bDeviceClass values.
499 * Matches based on device class/subclass/protocol specifications
500 * are slightly more general; use the USB_DEVICE_INFO macro, or
501 * its siblings. These are used with single-function devices
502 * where bDeviceClass doesn't specify that each interface has
505 * Matches based on interface class/subclass/protocol are the
506 * most general; they let drivers bind to any interface on a
507 * multiple-function device. Use the USB_INTERFACE_INFO
508 * macro, or its siblings, to match class-per-interface style
509 * devices (as recorded in bInterfaceClass).
511 * Note that an entry created by USB_INTERFACE_INFO won't match
512 * any interface if the device class is set to Vendor-Specific.
513 * This is deliberate; according to the USB spec the meanings of
514 * the interface class/subclass/protocol for these devices are also
515 * vendor-specific, and hence matching against a standard product
516 * class wouldn't work anyway. If you really want to use an
517 * interface-based match for such a device, create a match record
518 * that also specifies the vendor ID. (Unforunately there isn't a
519 * standard macro for creating records like this.)
521 * Within those groups, remember that not all combinations are
522 * meaningful. For example, don't give a product version range
523 * without vendor and product IDs; or specify a protocol without
524 * its associated class and subclass.
526 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
527 const struct usb_device_id *id)
529 /* proc_connectinfo in devio.c may call us with id == NULL. */
533 /* It is important to check that id->driver_info is nonzero,
534 since an entry that is all zeroes except for a nonzero
535 id->driver_info is the way to create an entry that
536 indicates that the driver want to examine every
537 device and interface. */
538 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
539 id->bInterfaceClass || id->driver_info; id++) {
540 if (usb_match_one_id(interface, id))
546 EXPORT_SYMBOL_GPL(usb_match_id);
548 static int usb_device_match(struct device *dev, struct device_driver *drv)
550 /* devices and interfaces are handled separately */
551 if (is_usb_device(dev)) {
553 /* interface drivers never match devices */
554 if (!is_usb_device_driver(drv))
557 /* TODO: Add real matching code */
561 struct usb_interface *intf;
562 struct usb_driver *usb_drv;
563 const struct usb_device_id *id;
565 /* device drivers never match interfaces */
566 if (is_usb_device_driver(drv))
569 intf = to_usb_interface(dev);
570 usb_drv = to_usb_driver(drv);
572 id = usb_match_id(intf, usb_drv->id_table);
576 id = usb_match_dynamic_id(intf, usb_drv);
584 #ifdef CONFIG_HOTPLUG
585 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
587 struct usb_device *usb_dev;
589 /* driver is often null here; dev_dbg() would oops */
590 pr_debug("usb %s: uevent\n", dev_name(dev));
592 if (is_usb_device(dev))
593 usb_dev = to_usb_device(dev);
595 struct usb_interface *intf = to_usb_interface(dev);
596 usb_dev = interface_to_usbdev(intf);
599 if (usb_dev->devnum < 0) {
600 pr_debug("usb %s: already deleted?\n", dev_name(dev));
604 pr_debug("usb %s: bus removed?\n", dev_name(dev));
608 #ifdef CONFIG_USB_DEVICEFS
609 /* If this is available, userspace programs can directly read
610 * all the device descriptors we don't tell them about. Or
611 * act as usermode drivers.
613 if (add_uevent_var(env, "DEVICE=/proc/bus/usb/%03d/%03d",
614 usb_dev->bus->busnum, usb_dev->devnum))
618 /* per-device configurations are common */
619 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
620 le16_to_cpu(usb_dev->descriptor.idVendor),
621 le16_to_cpu(usb_dev->descriptor.idProduct),
622 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
625 /* class-based driver binding models */
626 if (add_uevent_var(env, "TYPE=%d/%d/%d",
627 usb_dev->descriptor.bDeviceClass,
628 usb_dev->descriptor.bDeviceSubClass,
629 usb_dev->descriptor.bDeviceProtocol))
637 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
641 #endif /* CONFIG_HOTPLUG */
644 * usb_register_device_driver - register a USB device (not interface) driver
645 * @new_udriver: USB operations for the device driver
646 * @owner: module owner of this driver.
648 * Registers a USB device driver with the USB core. The list of
649 * unattached devices will be rescanned whenever a new driver is
650 * added, allowing the new driver to attach to any recognized devices.
651 * Returns a negative error code on failure and 0 on success.
653 int usb_register_device_driver(struct usb_device_driver *new_udriver,
654 struct module *owner)
661 new_udriver->drvwrap.for_devices = 1;
662 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
663 new_udriver->drvwrap.driver.bus = &usb_bus_type;
664 new_udriver->drvwrap.driver.probe = usb_probe_device;
665 new_udriver->drvwrap.driver.remove = usb_unbind_device;
666 new_udriver->drvwrap.driver.owner = owner;
668 retval = driver_register(&new_udriver->drvwrap.driver);
671 pr_info("%s: registered new device driver %s\n",
672 usbcore_name, new_udriver->name);
673 usbfs_update_special();
675 printk(KERN_ERR "%s: error %d registering device "
677 usbcore_name, retval, new_udriver->name);
682 EXPORT_SYMBOL_GPL(usb_register_device_driver);
685 * usb_deregister_device_driver - unregister a USB device (not interface) driver
686 * @udriver: USB operations of the device driver to unregister
687 * Context: must be able to sleep
689 * Unlinks the specified driver from the internal USB driver list.
691 void usb_deregister_device_driver(struct usb_device_driver *udriver)
693 pr_info("%s: deregistering device driver %s\n",
694 usbcore_name, udriver->name);
696 driver_unregister(&udriver->drvwrap.driver);
697 usbfs_update_special();
699 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
702 * usb_register_driver - register a USB interface driver
703 * @new_driver: USB operations for the interface driver
704 * @owner: module owner of this driver.
705 * @mod_name: module name string
707 * Registers a USB interface driver with the USB core. The list of
708 * unattached interfaces will be rescanned whenever a new driver is
709 * added, allowing the new driver to attach to any recognized interfaces.
710 * Returns a negative error code on failure and 0 on success.
712 * NOTE: if you want your driver to use the USB major number, you must call
713 * usb_register_dev() to enable that functionality. This function no longer
714 * takes care of that.
716 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
717 const char *mod_name)
724 new_driver->drvwrap.for_devices = 0;
725 new_driver->drvwrap.driver.name = (char *) new_driver->name;
726 new_driver->drvwrap.driver.bus = &usb_bus_type;
727 new_driver->drvwrap.driver.probe = usb_probe_interface;
728 new_driver->drvwrap.driver.remove = usb_unbind_interface;
729 new_driver->drvwrap.driver.owner = owner;
730 new_driver->drvwrap.driver.mod_name = mod_name;
731 spin_lock_init(&new_driver->dynids.lock);
732 INIT_LIST_HEAD(&new_driver->dynids.list);
734 retval = driver_register(&new_driver->drvwrap.driver);
737 pr_info("%s: registered new interface driver %s\n",
738 usbcore_name, new_driver->name);
739 usbfs_update_special();
740 usb_create_newid_file(new_driver);
742 printk(KERN_ERR "%s: error %d registering interface "
744 usbcore_name, retval, new_driver->name);
749 EXPORT_SYMBOL_GPL(usb_register_driver);
752 * usb_deregister - unregister a USB interface driver
753 * @driver: USB operations of the interface driver to unregister
754 * Context: must be able to sleep
756 * Unlinks the specified driver from the internal USB driver list.
758 * NOTE: If you called usb_register_dev(), you still need to call
759 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
760 * this * call will no longer do it for you.
762 void usb_deregister(struct usb_driver *driver)
764 pr_info("%s: deregistering interface driver %s\n",
765 usbcore_name, driver->name);
767 usb_remove_newid_file(driver);
768 usb_free_dynids(driver);
769 driver_unregister(&driver->drvwrap.driver);
771 usbfs_update_special();
773 EXPORT_SYMBOL_GPL(usb_deregister);
777 /* Caller has locked udev's pm_mutex */
778 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
780 struct usb_device_driver *udriver;
783 if (udev->state == USB_STATE_NOTATTACHED ||
784 udev->state == USB_STATE_SUSPENDED)
787 /* For devices that don't have a driver, we do a generic suspend. */
788 if (udev->dev.driver)
789 udriver = to_usb_device_driver(udev->dev.driver);
791 udev->do_remote_wakeup = 0;
792 udriver = &usb_generic_driver;
794 status = udriver->suspend(udev, msg);
797 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
801 /* Caller has locked udev's pm_mutex */
802 static int usb_resume_device(struct usb_device *udev)
804 struct usb_device_driver *udriver;
807 if (udev->state == USB_STATE_NOTATTACHED)
810 /* Can't resume it if it doesn't have a driver. */
811 if (udev->dev.driver == NULL) {
816 if (udev->quirks & USB_QUIRK_RESET_RESUME)
817 udev->reset_resume = 1;
819 udriver = to_usb_device_driver(udev->dev.driver);
820 status = udriver->resume(udev);
823 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
825 udev->autoresume_disabled = 0;
829 /* Caller has locked intf's usb_device's pm mutex */
830 static int usb_suspend_interface(struct usb_interface *intf, pm_message_t msg)
832 struct usb_driver *driver;
835 /* with no hardware, USB interfaces only use FREEZE and ON states */
836 if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
840 if (intf->condition == USB_INTERFACE_UNBOUND) /* This can't happen */
842 driver = to_usb_driver(intf->dev.driver);
844 if (driver->suspend && driver->resume) {
845 status = driver->suspend(intf, msg);
848 else if (!interface_to_usbdev(intf)->auto_pm)
849 dev_err(&intf->dev, "%s error %d\n",
853 * FIXME else if there's no suspend method, disconnect...
854 * Not possible if auto_pm is set...
856 dev_warn(&intf->dev, "no suspend for driver %s?\n",
862 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
866 /* Caller has locked intf's usb_device's pm_mutex */
867 static int usb_resume_interface(struct usb_interface *intf, int reset_resume)
869 struct usb_driver *driver;
872 if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
876 /* Don't let autoresume interfere with unbinding */
877 if (intf->condition == USB_INTERFACE_UNBINDING)
880 /* Can't resume it if it doesn't have a driver. */
881 if (intf->condition == USB_INTERFACE_UNBOUND) {
885 driver = to_usb_driver(intf->dev.driver);
888 if (driver->reset_resume) {
889 status = driver->reset_resume(intf);
891 dev_err(&intf->dev, "%s error %d\n",
892 "reset_resume", status);
894 /* status = -EOPNOTSUPP; */
895 dev_warn(&intf->dev, "no %s for driver %s?\n",
896 "reset_resume", driver->name);
899 if (driver->resume) {
900 status = driver->resume(intf);
902 dev_err(&intf->dev, "%s error %d\n",
905 /* status = -EOPNOTSUPP; */
906 dev_warn(&intf->dev, "no %s for driver %s?\n",
907 "resume", driver->name);
912 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
916 /* FIXME: Unbind the driver and reprobe if the resume failed
917 * (not possible if auto_pm is set) */
921 #ifdef CONFIG_USB_SUSPEND
923 /* Internal routine to check whether we may autosuspend a device. */
924 static int autosuspend_check(struct usb_device *udev, int reschedule)
927 struct usb_interface *intf;
928 unsigned long suspend_time, j;
930 /* For autosuspend, fail fast if anything is in use or autosuspend
931 * is disabled. Also fail if any interfaces require remote wakeup
932 * but it isn't available.
934 if (udev->pm_usage_cnt > 0)
936 if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
939 suspend_time = udev->last_busy + udev->autosuspend_delay;
940 if (udev->actconfig) {
941 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
942 intf = udev->actconfig->interface[i];
943 if (!is_active(intf))
945 if (intf->pm_usage_cnt > 0)
947 if (intf->needs_remote_wakeup &&
948 !udev->do_remote_wakeup) {
949 dev_dbg(&udev->dev, "remote wakeup needed "
950 "for autosuspend\n");
954 /* Don't allow autosuspend if the device will need
955 * a reset-resume and any of its interface drivers
956 * doesn't include support.
958 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
959 struct usb_driver *driver;
961 driver = to_usb_driver(intf->dev.driver);
962 if (!driver->reset_resume)
968 /* If everything is okay but the device hasn't been idle for long
969 * enough, queue a delayed autosuspend request. If the device
970 * _has_ been idle for long enough and the reschedule flag is set,
971 * likewise queue a delayed (1 second) autosuspend request.
974 if (time_before(j, suspend_time))
977 suspend_time = j + HZ;
979 if (!timer_pending(&udev->autosuspend.timer)) {
980 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
981 round_jiffies_relative(suspend_time - j));
990 static inline int autosuspend_check(struct usb_device *udev, int reschedule)
995 #endif /* CONFIG_USB_SUSPEND */
998 * usb_suspend_both - suspend a USB device and its interfaces
999 * @udev: the usb_device to suspend
1000 * @msg: Power Management message describing this state transition
1002 * This is the central routine for suspending USB devices. It calls the
1003 * suspend methods for all the interface drivers in @udev and then calls
1004 * the suspend method for @udev itself. If an error occurs at any stage,
1005 * all the interfaces which were suspended are resumed so that they remain
1006 * in the same state as the device.
1008 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
1009 * checks first to make sure that neither the device itself or any of its
1010 * active interfaces is in use (pm_usage_cnt is greater than 0). If they
1011 * are, the autosuspend fails.
1013 * If the suspend succeeds, the routine recursively queues an autosuspend
1014 * request for @udev's parent device, thereby propagating the change up
1015 * the device tree. If all of the parent's children are now suspended,
1016 * the parent will autosuspend in turn.
1018 * The suspend method calls are subject to mutual exclusion under control
1019 * of @udev's pm_mutex. Many of these calls are also under the protection
1020 * of @udev's device lock (including all requests originating outside the
1021 * USB subsystem), but autosuspend requests generated by a child device or
1022 * interface driver may not be. Usbcore will insure that the method calls
1023 * do not arrive during bind, unbind, or reset operations. However, drivers
1024 * must be prepared to handle suspend calls arriving at unpredictable times.
1025 * The only way to block such calls is to do an autoresume (preventing
1026 * autosuspends) while holding @udev's device lock (preventing outside
1029 * The caller must hold @udev->pm_mutex.
1031 * This routine can run only in process context.
1033 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1037 struct usb_interface *intf;
1038 struct usb_device *parent = udev->parent;
1040 if (udev->state == USB_STATE_NOTATTACHED ||
1041 udev->state == USB_STATE_SUSPENDED)
1044 udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
1046 if (udev->auto_pm) {
1047 status = autosuspend_check(udev, 0);
1052 /* Suspend all the interfaces and then udev itself */
1053 if (udev->actconfig) {
1054 for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
1055 intf = udev->actconfig->interface[i];
1056 status = usb_suspend_interface(intf, msg);
1062 status = usb_suspend_device(udev, msg);
1064 /* If the suspend failed, resume interfaces that did get suspended */
1067 intf = udev->actconfig->interface[i];
1068 usb_resume_interface(intf, 0);
1071 /* Try another autosuspend when the interfaces aren't busy */
1073 autosuspend_check(udev, status == -EBUSY);
1075 /* If the suspend succeeded then prevent any more URB submissions,
1076 * flush any outstanding URBs, and propagate the suspend up the tree.
1079 cancel_delayed_work(&udev->autosuspend);
1080 udev->can_submit = 0;
1081 for (i = 0; i < 16; ++i) {
1082 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1083 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1086 /* If this is just a FREEZE or a PRETHAW, udev might
1087 * not really be suspended. Only true suspends get
1088 * propagated up the device tree.
1090 if (parent && udev->state == USB_STATE_SUSPENDED)
1091 usb_autosuspend_device(parent);
1095 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1100 * usb_resume_both - resume a USB device and its interfaces
1101 * @udev: the usb_device to resume
1103 * This is the central routine for resuming USB devices. It calls the
1104 * the resume method for @udev and then calls the resume methods for all
1105 * the interface drivers in @udev.
1107 * Before starting the resume, the routine calls itself recursively for
1108 * the parent device of @udev, thereby propagating the change up the device
1109 * tree and assuring that @udev will be able to resume. If the parent is
1110 * unable to resume successfully, the routine fails.
1112 * The resume method calls are subject to mutual exclusion under control
1113 * of @udev's pm_mutex. Many of these calls are also under the protection
1114 * of @udev's device lock (including all requests originating outside the
1115 * USB subsystem), but autoresume requests generated by a child device or
1116 * interface driver may not be. Usbcore will insure that the method calls
1117 * do not arrive during bind, unbind, or reset operations. However, drivers
1118 * must be prepared to handle resume calls arriving at unpredictable times.
1119 * The only way to block such calls is to do an autoresume (preventing
1120 * other autoresumes) while holding @udev's device lock (preventing outside
1123 * The caller must hold @udev->pm_mutex.
1125 * This routine can run only in process context.
1127 static int usb_resume_both(struct usb_device *udev)
1131 struct usb_interface *intf;
1132 struct usb_device *parent = udev->parent;
1134 cancel_delayed_work(&udev->autosuspend);
1135 if (udev->state == USB_STATE_NOTATTACHED) {
1139 udev->can_submit = 1;
1141 /* Propagate the resume up the tree, if necessary */
1142 if (udev->state == USB_STATE_SUSPENDED) {
1143 if (udev->auto_pm && udev->autoresume_disabled) {
1148 status = usb_autoresume_device(parent);
1150 status = usb_resume_device(udev);
1151 if (status || udev->state ==
1152 USB_STATE_NOTATTACHED) {
1153 usb_autosuspend_device(parent);
1155 /* It's possible usb_resume_device()
1156 * failed after the port was
1157 * unsuspended, causing udev to be
1158 * logically disconnected. We don't
1159 * want usb_disconnect() to autosuspend
1160 * the parent again, so tell it that
1161 * udev disconnected while still
1164 USB_STATE_NOTATTACHED)
1165 udev->discon_suspended = 1;
1170 /* We can't progagate beyond the USB subsystem,
1171 * so if a root hub's controller is suspended
1172 * then we're stuck. */
1173 status = usb_resume_device(udev);
1175 } else if (udev->reset_resume)
1176 status = usb_resume_device(udev);
1178 if (status == 0 && udev->actconfig) {
1179 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1180 intf = udev->actconfig->interface[i];
1181 usb_resume_interface(intf, udev->reset_resume);
1186 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1188 udev->reset_resume = 0;
1192 #ifdef CONFIG_USB_SUSPEND
1194 /* Internal routine to adjust a device's usage counter and change
1195 * its autosuspend state.
1197 static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
1203 udev->pm_usage_cnt += inc_usage_cnt;
1204 WARN_ON(udev->pm_usage_cnt < 0);
1206 udev->last_busy = jiffies;
1207 if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
1208 if (udev->state == USB_STATE_SUSPENDED)
1209 status = usb_resume_both(udev);
1211 udev->pm_usage_cnt -= inc_usage_cnt;
1212 else if (inc_usage_cnt)
1213 udev->last_busy = jiffies;
1214 } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
1215 status = usb_suspend_both(udev, PMSG_SUSPEND);
1217 usb_pm_unlock(udev);
1221 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1222 void usb_autosuspend_work(struct work_struct *work)
1224 struct usb_device *udev =
1225 container_of(work, struct usb_device, autosuspend.work);
1227 usb_autopm_do_device(udev, 0);
1231 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1232 * @udev: the usb_device to autosuspend
1234 * This routine should be called when a core subsystem is finished using
1235 * @udev and wants to allow it to autosuspend. Examples would be when
1236 * @udev's device file in usbfs is closed or after a configuration change.
1238 * @udev's usage counter is decremented. If it or any of the usage counters
1239 * for an active interface is greater than 0, no autosuspend request will be
1240 * queued. (If an interface driver does not support autosuspend then its
1241 * usage counter is permanently positive.) Furthermore, if an interface
1242 * driver requires remote-wakeup capability during autosuspend but remote
1243 * wakeup is disabled, the autosuspend will fail.
1245 * Often the caller will hold @udev's device lock, but this is not
1248 * This routine can run only in process context.
1250 void usb_autosuspend_device(struct usb_device *udev)
1254 status = usb_autopm_do_device(udev, -1);
1255 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1256 __func__, udev->pm_usage_cnt);
1260 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1261 * @udev: the usb_device to autosuspend
1263 * This routine should be called when a core subsystem thinks @udev may
1264 * be ready to autosuspend.
1266 * @udev's usage counter left unchanged. If it or any of the usage counters
1267 * for an active interface is greater than 0, or autosuspend is not allowed
1268 * for any other reason, no autosuspend request will be queued.
1270 * This routine can run only in process context.
1272 void usb_try_autosuspend_device(struct usb_device *udev)
1274 usb_autopm_do_device(udev, 0);
1275 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1276 __func__, udev->pm_usage_cnt);
1280 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1281 * @udev: the usb_device to autoresume
1283 * This routine should be called when a core subsystem wants to use @udev
1284 * and needs to guarantee that it is not suspended. No autosuspend will
1285 * occur until usb_autosuspend_device is called. (Note that this will not
1286 * prevent suspend events originating in the PM core.) Examples would be
1287 * when @udev's device file in usbfs is opened or when a remote-wakeup
1288 * request is received.
1290 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1291 * However if the autoresume fails then the usage counter is re-decremented.
1293 * Often the caller will hold @udev's device lock, but this is not
1294 * necessary (and attempting it might cause deadlock).
1296 * This routine can run only in process context.
1298 int usb_autoresume_device(struct usb_device *udev)
1302 status = usb_autopm_do_device(udev, 1);
1303 dev_vdbg(&udev->dev, "%s: status %d cnt %d\n",
1304 __func__, status, udev->pm_usage_cnt);
1308 /* Internal routine to adjust an interface's usage counter and change
1309 * its device's autosuspend state.
1311 static int usb_autopm_do_interface(struct usb_interface *intf,
1314 struct usb_device *udev = interface_to_usbdev(intf);
1318 if (intf->condition == USB_INTERFACE_UNBOUND)
1322 intf->pm_usage_cnt += inc_usage_cnt;
1323 udev->last_busy = jiffies;
1324 if (inc_usage_cnt >= 0 && intf->pm_usage_cnt > 0) {
1325 if (udev->state == USB_STATE_SUSPENDED)
1326 status = usb_resume_both(udev);
1328 intf->pm_usage_cnt -= inc_usage_cnt;
1330 udev->last_busy = jiffies;
1331 } else if (inc_usage_cnt <= 0 && intf->pm_usage_cnt <= 0) {
1332 status = usb_suspend_both(udev, PMSG_SUSPEND);
1335 usb_pm_unlock(udev);
1340 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1341 * @intf: the usb_interface whose counter should be decremented
1343 * This routine should be called by an interface driver when it is
1344 * finished using @intf and wants to allow it to autosuspend. A typical
1345 * example would be a character-device driver when its device file is
1348 * The routine decrements @intf's usage counter. When the counter reaches
1349 * 0, a delayed autosuspend request for @intf's device is queued. When
1350 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1351 * the other usage counters for the sibling interfaces and @intf's
1352 * usb_device, the device and all its interfaces will be autosuspended.
1354 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1355 * core will not change its value other than the increment and decrement
1356 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1357 * may use this simple counter-oriented discipline or may set the value
1360 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1361 * take place only if the device's remote-wakeup facility is enabled.
1363 * Suspend method calls queued by this routine can arrive at any time
1364 * while @intf is resumed and its usage counter is equal to 0. They are
1365 * not protected by the usb_device's lock but only by its pm_mutex.
1366 * Drivers must provide their own synchronization.
1368 * This routine can run only in process context.
1370 void usb_autopm_put_interface(struct usb_interface *intf)
1374 status = usb_autopm_do_interface(intf, -1);
1375 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1376 __func__, status, intf->pm_usage_cnt);
1378 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1381 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1382 * @intf: the usb_interface whose counter should be incremented
1384 * This routine should be called by an interface driver when it wants to
1385 * use @intf and needs to guarantee that it is not suspended. In addition,
1386 * the routine prevents @intf from being autosuspended subsequently. (Note
1387 * that this will not prevent suspend events originating in the PM core.)
1388 * This prevention will persist until usb_autopm_put_interface() is called
1389 * or @intf is unbound. A typical example would be a character-device
1390 * driver when its device file is opened.
1393 * The routine increments @intf's usage counter. (However if the
1394 * autoresume fails then the counter is re-decremented.) So long as the
1395 * counter is greater than 0, autosuspend will not be allowed for @intf
1396 * or its usb_device. When the driver is finished using @intf it should
1397 * call usb_autopm_put_interface() to decrement the usage counter and
1398 * queue a delayed autosuspend request (if the counter is <= 0).
1401 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1402 * core will not change its value other than the increment and decrement
1403 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1404 * may use this simple counter-oriented discipline or may set the value
1407 * Resume method calls generated by this routine can arrive at any time
1408 * while @intf is suspended. They are not protected by the usb_device's
1409 * lock but only by its pm_mutex. Drivers must provide their own
1412 * This routine can run only in process context.
1414 int usb_autopm_get_interface(struct usb_interface *intf)
1418 status = usb_autopm_do_interface(intf, 1);
1419 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1420 __func__, status, intf->pm_usage_cnt);
1423 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1426 * usb_autopm_set_interface - set a USB interface's autosuspend state
1427 * @intf: the usb_interface whose state should be set
1429 * This routine sets the autosuspend state of @intf's device according
1430 * to @intf's usage counter, which the caller must have set previously.
1431 * If the counter is <= 0, the device is autosuspended (if it isn't
1432 * already suspended and if nothing else prevents the autosuspend). If
1433 * the counter is > 0, the device is autoresumed (if it isn't already
1436 int usb_autopm_set_interface(struct usb_interface *intf)
1440 status = usb_autopm_do_interface(intf, 0);
1441 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1442 __func__, status, intf->pm_usage_cnt);
1445 EXPORT_SYMBOL_GPL(usb_autopm_set_interface);
1449 void usb_autosuspend_work(struct work_struct *work)
1452 #endif /* CONFIG_USB_SUSPEND */
1455 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1456 * @udev: the usb_device to suspend
1457 * @msg: Power Management message describing this state transition
1459 * This routine handles external suspend requests: ones not generated
1460 * internally by a USB driver (autosuspend) but rather coming from the user
1461 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1462 * out regardless of @udev's usage counter or those of its interfaces,
1463 * and regardless of whether or not remote wakeup is enabled. Of course,
1464 * interface drivers still have the option of failing the suspend (if
1465 * there are unsuspended children, for example).
1467 * The caller must hold @udev's device lock.
1469 int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
1475 status = usb_suspend_both(udev, msg);
1476 usb_pm_unlock(udev);
1481 * usb_external_resume_device - external resume of a USB device and its interfaces
1482 * @udev: the usb_device to resume
1484 * This routine handles external resume requests: ones not generated
1485 * internally by a USB driver (autoresume) but rather coming from the user
1486 * (via sysfs), the PM core (system resume), or the device itself (remote
1487 * wakeup). @udev's usage counter is unaffected.
1489 * The caller must hold @udev's device lock.
1491 int usb_external_resume_device(struct usb_device *udev)
1497 status = usb_resume_both(udev);
1498 udev->last_busy = jiffies;
1499 usb_pm_unlock(udev);
1501 /* Now that the device is awake, we can start trying to autosuspend
1504 usb_try_autosuspend_device(udev);
1508 static int usb_suspend(struct device *dev, pm_message_t message)
1510 struct usb_device *udev;
1512 if (!is_usb_device(dev)) /* Ignore PM for interfaces */
1514 udev = to_usb_device(dev);
1516 /* If udev is already suspended, we can skip this suspend and
1517 * we should also skip the upcoming system resume. High-speed
1518 * root hubs are an exception; they need to resume whenever the
1519 * system wakes up in order for USB-PERSIST port handover to work
1522 if (udev->state == USB_STATE_SUSPENDED) {
1523 if (udev->parent || udev->speed != USB_SPEED_HIGH)
1524 udev->skip_sys_resume = 1;
1528 udev->skip_sys_resume = 0;
1529 return usb_external_suspend_device(udev, message);
1532 static int usb_resume(struct device *dev)
1534 struct usb_device *udev;
1536 if (!is_usb_device(dev)) /* Ignore PM for interfaces */
1538 udev = to_usb_device(dev);
1540 /* If udev->skip_sys_resume is set then udev was already suspended
1541 * when the system sleep started, so we don't want to resume it
1542 * during this system wakeup.
1544 if (udev->skip_sys_resume)
1546 return usb_external_resume_device(udev);
1551 #define usb_suspend NULL
1552 #define usb_resume NULL
1554 #endif /* CONFIG_PM */
1556 struct bus_type usb_bus_type = {
1558 .match = usb_device_match,
1559 .uevent = usb_uevent,
1560 .suspend = usb_suspend,
1561 .resume = usb_resume,