2 * drivers/usb/driver.c - most of the driver model stuff for usb
4 * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
6 * based on drivers/usb/usb.c which had the following copyrights:
7 * (C) Copyright Linus Torvalds 1999
8 * (C) Copyright Johannes Erdfelt 1999-2001
9 * (C) Copyright Andreas Gal 1999
10 * (C) Copyright Gregory P. Smith 1999
11 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
12 * (C) Copyright Randy Dunlap 2000
13 * (C) Copyright David Brownell 2000-2004
14 * (C) Copyright Yggdrasil Computing, Inc. 2000
15 * (usb_device_id matching changes by Adam J. Richter)
16 * (C) Copyright Greg Kroah-Hartman 2002-2003
18 * NOTE! This is not actually a driver at all, rather this is
19 * just a collection of helper routines that implement the
20 * matching, probing, releasing, suspending and resuming for
25 #include <linux/device.h>
26 #include <linux/slab.h>
27 #include <linux/export.h>
28 #include <linux/usb.h>
29 #include <linux/usb/quirks.h>
30 #include <linux/usb/hcd.h>
38 * Adds a new dynamic USBdevice ID to this driver,
39 * and cause the driver to probe for all devices again.
41 ssize_t usb_store_new_id(struct usb_dynids *dynids,
42 struct device_driver *driver,
43 const char *buf, size_t count)
45 struct usb_dynid *dynid;
48 unsigned int bInterfaceClass = 0;
52 fields = sscanf(buf, "%x %x %x", &idVendor, &idProduct,
57 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
61 INIT_LIST_HEAD(&dynid->node);
62 dynid->id.idVendor = idVendor;
63 dynid->id.idProduct = idProduct;
64 dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
66 dynid->id.bInterfaceClass = (u8)bInterfaceClass;
67 dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
70 spin_lock(&dynids->lock);
71 list_add_tail(&dynid->node, &dynids->list);
72 spin_unlock(&dynids->lock);
74 retval = driver_attach(driver);
80 EXPORT_SYMBOL_GPL(usb_store_new_id);
82 ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf)
84 struct usb_dynid *dynid;
87 list_for_each_entry(dynid, &dynids->list, node)
88 if (dynid->id.bInterfaceClass != 0)
89 count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x %02x\n",
90 dynid->id.idVendor, dynid->id.idProduct,
91 dynid->id.bInterfaceClass);
93 count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x\n",
94 dynid->id.idVendor, dynid->id.idProduct);
97 EXPORT_SYMBOL_GPL(usb_show_dynids);
99 static ssize_t show_dynids(struct device_driver *driver, char *buf)
101 struct usb_driver *usb_drv = to_usb_driver(driver);
103 return usb_show_dynids(&usb_drv->dynids, buf);
106 static ssize_t store_new_id(struct device_driver *driver,
107 const char *buf, size_t count)
109 struct usb_driver *usb_drv = to_usb_driver(driver);
111 return usb_store_new_id(&usb_drv->dynids, driver, buf, count);
113 static DRIVER_ATTR(new_id, S_IRUGO | S_IWUSR, show_dynids, store_new_id);
116 * store_remove_id - remove a USB device ID from this driver
117 * @driver: target device driver
118 * @buf: buffer for scanning device ID data
121 * Removes a dynamic usb device ID from this driver.
124 store_remove_id(struct device_driver *driver, const char *buf, size_t count)
126 struct usb_dynid *dynid, *n;
127 struct usb_driver *usb_driver = to_usb_driver(driver);
133 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
137 spin_lock(&usb_driver->dynids.lock);
138 list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) {
139 struct usb_device_id *id = &dynid->id;
140 if ((id->idVendor == idVendor) &&
141 (id->idProduct == idProduct)) {
142 list_del(&dynid->node);
148 spin_unlock(&usb_driver->dynids.lock);
154 static DRIVER_ATTR(remove_id, S_IRUGO | S_IWUSR, show_dynids, store_remove_id);
156 static int usb_create_newid_files(struct usb_driver *usb_drv)
160 if (usb_drv->no_dynamic_id)
163 if (usb_drv->probe != NULL) {
164 error = driver_create_file(&usb_drv->drvwrap.driver,
165 &driver_attr_new_id);
167 error = driver_create_file(&usb_drv->drvwrap.driver,
168 &driver_attr_remove_id);
170 driver_remove_file(&usb_drv->drvwrap.driver,
171 &driver_attr_new_id);
178 static void usb_remove_newid_files(struct usb_driver *usb_drv)
180 if (usb_drv->no_dynamic_id)
183 if (usb_drv->probe != NULL) {
184 driver_remove_file(&usb_drv->drvwrap.driver,
185 &driver_attr_remove_id);
186 driver_remove_file(&usb_drv->drvwrap.driver,
187 &driver_attr_new_id);
191 static void usb_free_dynids(struct usb_driver *usb_drv)
193 struct usb_dynid *dynid, *n;
195 spin_lock(&usb_drv->dynids.lock);
196 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
197 list_del(&dynid->node);
200 spin_unlock(&usb_drv->dynids.lock);
203 static inline int usb_create_newid_files(struct usb_driver *usb_drv)
208 static void usb_remove_newid_files(struct usb_driver *usb_drv)
212 static inline void usb_free_dynids(struct usb_driver *usb_drv)
217 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
218 struct usb_driver *drv)
220 struct usb_dynid *dynid;
222 spin_lock(&drv->dynids.lock);
223 list_for_each_entry(dynid, &drv->dynids.list, node) {
224 if (usb_match_one_id(intf, &dynid->id)) {
225 spin_unlock(&drv->dynids.lock);
229 spin_unlock(&drv->dynids.lock);
234 /* called from driver core with dev locked */
235 static int usb_probe_device(struct device *dev)
237 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
238 struct usb_device *udev = to_usb_device(dev);
241 dev_dbg(dev, "%s\n", __func__);
243 /* TODO: Add real matching code */
245 /* The device should always appear to be in use
246 * unless the driver suports autosuspend.
248 if (!udriver->supports_autosuspend)
249 error = usb_autoresume_device(udev);
252 error = udriver->probe(udev);
256 /* called from driver core with dev locked */
257 static int usb_unbind_device(struct device *dev)
259 struct usb_device *udev = to_usb_device(dev);
260 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
262 udriver->disconnect(udev);
263 if (!udriver->supports_autosuspend)
264 usb_autosuspend_device(udev);
269 * Cancel any pending scheduled resets
271 * [see usb_queue_reset_device()]
273 * Called after unconfiguring / when releasing interfaces. See
274 * comments in __usb_queue_reset_device() regarding
275 * udev->reset_running.
277 static void usb_cancel_queued_reset(struct usb_interface *iface)
279 if (iface->reset_running == 0)
280 cancel_work_sync(&iface->reset_ws);
283 /* called from driver core with dev locked */
284 static int usb_probe_interface(struct device *dev)
286 struct usb_driver *driver = to_usb_driver(dev->driver);
287 struct usb_interface *intf = to_usb_interface(dev);
288 struct usb_device *udev = interface_to_usbdev(intf);
289 const struct usb_device_id *id;
291 int lpm_disable_error;
293 dev_dbg(dev, "%s\n", __func__);
295 intf->needs_binding = 0;
297 if (usb_device_is_owned(udev))
300 if (udev->authorized == 0) {
301 dev_err(&intf->dev, "Device is not authorized for usage\n");
305 id = usb_match_id(intf, driver->id_table);
307 id = usb_match_dynamic_id(intf, driver);
311 dev_dbg(dev, "%s - got id\n", __func__);
313 error = usb_autoresume_device(udev);
317 intf->condition = USB_INTERFACE_BINDING;
319 /* Probed interfaces are initially active. They are
320 * runtime-PM-enabled only if the driver has autosuspend support.
321 * They are sensitive to their children's power states.
323 pm_runtime_set_active(dev);
324 pm_suspend_ignore_children(dev, false);
325 if (driver->supports_autosuspend)
326 pm_runtime_enable(dev);
328 /* If the new driver doesn't allow hub-initiated LPM, and we can't
329 * disable hub-initiated LPM, then fail the probe.
331 * Otherwise, leaving LPM enabled should be harmless, because the
332 * endpoint intervals should remain the same, and the U1/U2 timeouts
333 * should remain the same.
335 * If we need to install alt setting 0 before probe, or another alt
336 * setting during probe, that should also be fine. usb_set_interface()
337 * will attempt to disable LPM, and fail if it can't disable it.
339 lpm_disable_error = usb_unlocked_disable_lpm(udev);
340 if (lpm_disable_error && driver->disable_hub_initiated_lpm) {
341 dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n.",
342 __func__, driver->name);
343 error = lpm_disable_error;
347 /* Carry out a deferred switch to altsetting 0 */
348 if (intf->needs_altsetting0) {
349 error = usb_set_interface(udev, intf->altsetting[0].
350 desc.bInterfaceNumber, 0);
353 intf->needs_altsetting0 = 0;
356 error = driver->probe(intf, id);
360 intf->condition = USB_INTERFACE_BOUND;
362 /* If the LPM disable succeeded, balance the ref counts. */
363 if (!lpm_disable_error)
364 usb_unlocked_enable_lpm(udev);
366 usb_autosuspend_device(udev);
370 usb_set_intfdata(intf, NULL);
371 intf->needs_remote_wakeup = 0;
372 intf->condition = USB_INTERFACE_UNBOUND;
373 usb_cancel_queued_reset(intf);
375 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
376 if (driver->supports_autosuspend)
377 pm_runtime_disable(dev);
378 pm_runtime_set_suspended(dev);
380 usb_autosuspend_device(udev);
384 /* called from driver core with dev locked */
385 static int usb_unbind_interface(struct device *dev)
387 struct usb_driver *driver = to_usb_driver(dev->driver);
388 struct usb_interface *intf = to_usb_interface(dev);
389 struct usb_device *udev;
390 int error, r, lpm_disable_error;
392 intf->condition = USB_INTERFACE_UNBINDING;
394 /* Autoresume for set_interface call below */
395 udev = interface_to_usbdev(intf);
396 error = usb_autoresume_device(udev);
398 /* Hub-initiated LPM policy may change, so attempt to disable LPM until
399 * the driver is unbound. If LPM isn't disabled, that's fine because it
400 * wouldn't be enabled unless all the bound interfaces supported
403 lpm_disable_error = usb_unlocked_disable_lpm(udev);
405 /* Terminate all URBs for this interface unless the driver
406 * supports "soft" unbinding.
408 if (!driver->soft_unbind)
409 usb_disable_interface(udev, intf, false);
411 driver->disconnect(intf);
412 usb_cancel_queued_reset(intf);
414 /* Reset other interface state.
415 * We cannot do a Set-Interface if the device is suspended or
416 * if it is prepared for a system sleep (since installing a new
417 * altsetting means creating new endpoint device entries).
418 * When either of these happens, defer the Set-Interface.
420 if (intf->cur_altsetting->desc.bAlternateSetting == 0) {
421 /* Already in altsetting 0 so skip Set-Interface.
422 * Just re-enable it without affecting the endpoint toggles.
424 usb_enable_interface(udev, intf, false);
425 } else if (!error && !intf->dev.power.is_prepared) {
426 r = usb_set_interface(udev, intf->altsetting[0].
427 desc.bInterfaceNumber, 0);
429 intf->needs_altsetting0 = 1;
431 intf->needs_altsetting0 = 1;
433 usb_set_intfdata(intf, NULL);
435 intf->condition = USB_INTERFACE_UNBOUND;
436 intf->needs_remote_wakeup = 0;
438 /* Attempt to re-enable USB3 LPM, if the disable succeeded. */
439 if (!lpm_disable_error)
440 usb_unlocked_enable_lpm(udev);
442 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
443 if (driver->supports_autosuspend)
444 pm_runtime_disable(dev);
445 pm_runtime_set_suspended(dev);
447 /* Undo any residual pm_autopm_get_interface_* calls */
448 for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r)
449 usb_autopm_put_interface_no_suspend(intf);
450 atomic_set(&intf->pm_usage_cnt, 0);
453 usb_autosuspend_device(udev);
459 * usb_driver_claim_interface - bind a driver to an interface
460 * @driver: the driver to be bound
461 * @iface: the interface to which it will be bound; must be in the
462 * usb device's active configuration
463 * @priv: driver data associated with that interface
465 * This is used by usb device drivers that need to claim more than one
466 * interface on a device when probing (audio and acm are current examples).
467 * No device driver should directly modify internal usb_interface or
468 * usb_device structure members.
470 * Few drivers should need to use this routine, since the most natural
471 * way to bind to an interface is to return the private data from
472 * the driver's probe() method.
474 * Callers must own the device lock, so driver probe() entries don't need
475 * extra locking, but other call contexts may need to explicitly claim that
478 int usb_driver_claim_interface(struct usb_driver *driver,
479 struct usb_interface *iface, void *priv)
481 struct device *dev = &iface->dev;
482 struct usb_device *udev;
484 int lpm_disable_error;
489 udev = interface_to_usbdev(iface);
491 dev->driver = &driver->drvwrap.driver;
492 usb_set_intfdata(iface, priv);
493 iface->needs_binding = 0;
495 iface->condition = USB_INTERFACE_BOUND;
497 /* Disable LPM until this driver is bound. */
498 lpm_disable_error = usb_unlocked_disable_lpm(udev);
499 if (lpm_disable_error && driver->disable_hub_initiated_lpm) {
500 dev_err(&iface->dev, "%s Failed to disable LPM for driver %s\n.",
501 __func__, driver->name);
505 /* Claimed interfaces are initially inactive (suspended) and
506 * runtime-PM-enabled, but only if the driver has autosuspend
507 * support. Otherwise they are marked active, to prevent the
508 * device from being autosuspended, but left disabled. In either
509 * case they are sensitive to their children's power states.
511 pm_suspend_ignore_children(dev, false);
512 if (driver->supports_autosuspend)
513 pm_runtime_enable(dev);
515 pm_runtime_set_active(dev);
517 /* if interface was already added, bind now; else let
518 * the future device_add() bind it, bypassing probe()
520 if (device_is_registered(dev))
521 retval = device_bind_driver(dev);
523 /* Attempt to re-enable USB3 LPM, if the disable was successful. */
524 if (!lpm_disable_error)
525 usb_unlocked_enable_lpm(udev);
529 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
532 * usb_driver_release_interface - unbind a driver from an interface
533 * @driver: the driver to be unbound
534 * @iface: the interface from which it will be unbound
536 * This can be used by drivers to release an interface without waiting
537 * for their disconnect() methods to be called. In typical cases this
538 * also causes the driver disconnect() method to be called.
540 * This call is synchronous, and may not be used in an interrupt context.
541 * Callers must own the device lock, so driver disconnect() entries don't
542 * need extra locking, but other call contexts may need to explicitly claim
545 void usb_driver_release_interface(struct usb_driver *driver,
546 struct usb_interface *iface)
548 struct device *dev = &iface->dev;
550 /* this should never happen, don't release something that's not ours */
551 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
554 /* don't release from within disconnect() */
555 if (iface->condition != USB_INTERFACE_BOUND)
557 iface->condition = USB_INTERFACE_UNBINDING;
559 /* Release via the driver core only if the interface
560 * has already been registered
562 if (device_is_registered(dev)) {
563 device_release_driver(dev);
566 usb_unbind_interface(dev);
571 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
573 /* returns 0 if no match, 1 if match */
574 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
576 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
577 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
580 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
581 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
584 /* No need to test id->bcdDevice_lo != 0, since 0 is never
585 greater than any unsigned number. */
586 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
587 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
590 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
591 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
594 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
595 (id->bDeviceClass != dev->descriptor.bDeviceClass))
598 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
599 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
602 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
603 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
609 /* returns 0 if no match, 1 if match */
610 int usb_match_one_id(struct usb_interface *interface,
611 const struct usb_device_id *id)
613 struct usb_host_interface *intf;
614 struct usb_device *dev;
616 /* proc_connectinfo in devio.c may call us with id == NULL. */
620 intf = interface->cur_altsetting;
621 dev = interface_to_usbdev(interface);
623 if (!usb_match_device(dev, id))
626 /* The interface class, subclass, protocol and number should never be
627 * checked for a match if the device class is Vendor Specific,
628 * unless the match record specifies the Vendor ID. */
629 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
630 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
631 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
632 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
633 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
634 USB_DEVICE_ID_MATCH_INT_NUMBER)))
637 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
638 (id->bInterfaceClass != intf->desc.bInterfaceClass))
641 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
642 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
645 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
646 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
649 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
650 (id->bInterfaceNumber != intf->desc.bInterfaceNumber))
655 EXPORT_SYMBOL_GPL(usb_match_one_id);
658 * usb_match_id - find first usb_device_id matching device or interface
659 * @interface: the interface of interest
660 * @id: array of usb_device_id structures, terminated by zero entry
662 * usb_match_id searches an array of usb_device_id's and returns
663 * the first one matching the device or interface, or null.
664 * This is used when binding (or rebinding) a driver to an interface.
665 * Most USB device drivers will use this indirectly, through the usb core,
666 * but some layered driver frameworks use it directly.
667 * These device tables are exported with MODULE_DEVICE_TABLE, through
668 * modutils, to support the driver loading functionality of USB hotplugging.
672 * The "match_flags" element in a usb_device_id controls which
673 * members are used. If the corresponding bit is set, the
674 * value in the device_id must match its corresponding member
675 * in the device or interface descriptor, or else the device_id
678 * "driver_info" is normally used only by device drivers,
679 * but you can create a wildcard "matches anything" usb_device_id
680 * as a driver's "modules.usbmap" entry if you provide an id with
681 * only a nonzero "driver_info" field. If you do this, the USB device
682 * driver's probe() routine should use additional intelligence to
683 * decide whether to bind to the specified interface.
685 * What Makes Good usb_device_id Tables:
687 * The match algorithm is very simple, so that intelligence in
688 * driver selection must come from smart driver id records.
689 * Unless you have good reasons to use another selection policy,
690 * provide match elements only in related groups, and order match
691 * specifiers from specific to general. Use the macros provided
692 * for that purpose if you can.
694 * The most specific match specifiers use device descriptor
695 * data. These are commonly used with product-specific matches;
696 * the USB_DEVICE macro lets you provide vendor and product IDs,
697 * and you can also match against ranges of product revisions.
698 * These are widely used for devices with application or vendor
699 * specific bDeviceClass values.
701 * Matches based on device class/subclass/protocol specifications
702 * are slightly more general; use the USB_DEVICE_INFO macro, or
703 * its siblings. These are used with single-function devices
704 * where bDeviceClass doesn't specify that each interface has
707 * Matches based on interface class/subclass/protocol are the
708 * most general; they let drivers bind to any interface on a
709 * multiple-function device. Use the USB_INTERFACE_INFO
710 * macro, or its siblings, to match class-per-interface style
711 * devices (as recorded in bInterfaceClass).
713 * Note that an entry created by USB_INTERFACE_INFO won't match
714 * any interface if the device class is set to Vendor-Specific.
715 * This is deliberate; according to the USB spec the meanings of
716 * the interface class/subclass/protocol for these devices are also
717 * vendor-specific, and hence matching against a standard product
718 * class wouldn't work anyway. If you really want to use an
719 * interface-based match for such a device, create a match record
720 * that also specifies the vendor ID. (Unforunately there isn't a
721 * standard macro for creating records like this.)
723 * Within those groups, remember that not all combinations are
724 * meaningful. For example, don't give a product version range
725 * without vendor and product IDs; or specify a protocol without
726 * its associated class and subclass.
728 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
729 const struct usb_device_id *id)
731 /* proc_connectinfo in devio.c may call us with id == NULL. */
735 /* It is important to check that id->driver_info is nonzero,
736 since an entry that is all zeroes except for a nonzero
737 id->driver_info is the way to create an entry that
738 indicates that the driver want to examine every
739 device and interface. */
740 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
741 id->bInterfaceClass || id->driver_info; id++) {
742 if (usb_match_one_id(interface, id))
748 EXPORT_SYMBOL_GPL(usb_match_id);
750 static int usb_device_match(struct device *dev, struct device_driver *drv)
752 /* devices and interfaces are handled separately */
753 if (is_usb_device(dev)) {
755 /* interface drivers never match devices */
756 if (!is_usb_device_driver(drv))
759 /* TODO: Add real matching code */
762 } else if (is_usb_interface(dev)) {
763 struct usb_interface *intf;
764 struct usb_driver *usb_drv;
765 const struct usb_device_id *id;
767 /* device drivers never match interfaces */
768 if (is_usb_device_driver(drv))
771 intf = to_usb_interface(dev);
772 usb_drv = to_usb_driver(drv);
774 id = usb_match_id(intf, usb_drv->id_table);
778 id = usb_match_dynamic_id(intf, usb_drv);
786 #ifdef CONFIG_HOTPLUG
787 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
789 struct usb_device *usb_dev;
791 if (is_usb_device(dev)) {
792 usb_dev = to_usb_device(dev);
793 } else if (is_usb_interface(dev)) {
794 struct usb_interface *intf = to_usb_interface(dev);
796 usb_dev = interface_to_usbdev(intf);
801 if (usb_dev->devnum < 0) {
802 /* driver is often null here; dev_dbg() would oops */
803 pr_debug("usb %s: already deleted?\n", dev_name(dev));
807 pr_debug("usb %s: bus removed?\n", dev_name(dev));
811 /* per-device configurations are common */
812 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
813 le16_to_cpu(usb_dev->descriptor.idVendor),
814 le16_to_cpu(usb_dev->descriptor.idProduct),
815 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
818 /* class-based driver binding models */
819 if (add_uevent_var(env, "TYPE=%d/%d/%d",
820 usb_dev->descriptor.bDeviceClass,
821 usb_dev->descriptor.bDeviceSubClass,
822 usb_dev->descriptor.bDeviceProtocol))
830 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
834 #endif /* CONFIG_HOTPLUG */
837 * usb_register_device_driver - register a USB device (not interface) driver
838 * @new_udriver: USB operations for the device driver
839 * @owner: module owner of this driver.
841 * Registers a USB device driver with the USB core. The list of
842 * unattached devices will be rescanned whenever a new driver is
843 * added, allowing the new driver to attach to any recognized devices.
844 * Returns a negative error code on failure and 0 on success.
846 int usb_register_device_driver(struct usb_device_driver *new_udriver,
847 struct module *owner)
854 new_udriver->drvwrap.for_devices = 1;
855 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
856 new_udriver->drvwrap.driver.bus = &usb_bus_type;
857 new_udriver->drvwrap.driver.probe = usb_probe_device;
858 new_udriver->drvwrap.driver.remove = usb_unbind_device;
859 new_udriver->drvwrap.driver.owner = owner;
861 retval = driver_register(&new_udriver->drvwrap.driver);
864 pr_info("%s: registered new device driver %s\n",
865 usbcore_name, new_udriver->name);
867 printk(KERN_ERR "%s: error %d registering device "
869 usbcore_name, retval, new_udriver->name);
873 EXPORT_SYMBOL_GPL(usb_register_device_driver);
876 * usb_deregister_device_driver - unregister a USB device (not interface) driver
877 * @udriver: USB operations of the device driver to unregister
878 * Context: must be able to sleep
880 * Unlinks the specified driver from the internal USB driver list.
882 void usb_deregister_device_driver(struct usb_device_driver *udriver)
884 pr_info("%s: deregistering device driver %s\n",
885 usbcore_name, udriver->name);
887 driver_unregister(&udriver->drvwrap.driver);
889 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
892 * usb_register_driver - register a USB interface driver
893 * @new_driver: USB operations for the interface driver
894 * @owner: module owner of this driver.
895 * @mod_name: module name string
897 * Registers a USB interface driver with the USB core. The list of
898 * unattached interfaces will be rescanned whenever a new driver is
899 * added, allowing the new driver to attach to any recognized interfaces.
900 * Returns a negative error code on failure and 0 on success.
902 * NOTE: if you want your driver to use the USB major number, you must call
903 * usb_register_dev() to enable that functionality. This function no longer
904 * takes care of that.
906 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
907 const char *mod_name)
914 new_driver->drvwrap.for_devices = 0;
915 new_driver->drvwrap.driver.name = (char *) new_driver->name;
916 new_driver->drvwrap.driver.bus = &usb_bus_type;
917 new_driver->drvwrap.driver.probe = usb_probe_interface;
918 new_driver->drvwrap.driver.remove = usb_unbind_interface;
919 new_driver->drvwrap.driver.owner = owner;
920 new_driver->drvwrap.driver.mod_name = mod_name;
921 spin_lock_init(&new_driver->dynids.lock);
922 INIT_LIST_HEAD(&new_driver->dynids.list);
924 retval = driver_register(&new_driver->drvwrap.driver);
928 retval = usb_create_newid_files(new_driver);
932 pr_info("%s: registered new interface driver %s\n",
933 usbcore_name, new_driver->name);
939 driver_unregister(&new_driver->drvwrap.driver);
941 printk(KERN_ERR "%s: error %d registering interface "
943 usbcore_name, retval, new_driver->name);
946 EXPORT_SYMBOL_GPL(usb_register_driver);
949 * usb_deregister - unregister a USB interface driver
950 * @driver: USB operations of the interface driver to unregister
951 * Context: must be able to sleep
953 * Unlinks the specified driver from the internal USB driver list.
955 * NOTE: If you called usb_register_dev(), you still need to call
956 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
957 * this * call will no longer do it for you.
959 void usb_deregister(struct usb_driver *driver)
961 pr_info("%s: deregistering interface driver %s\n",
962 usbcore_name, driver->name);
964 usb_remove_newid_files(driver);
965 driver_unregister(&driver->drvwrap.driver);
966 usb_free_dynids(driver);
968 EXPORT_SYMBOL_GPL(usb_deregister);
970 /* Forced unbinding of a USB interface driver, either because
971 * it doesn't support pre_reset/post_reset/reset_resume or
972 * because it doesn't support suspend/resume.
974 * The caller must hold @intf's device's lock, but not its pm_mutex
975 * and not @intf->dev.sem.
977 void usb_forced_unbind_intf(struct usb_interface *intf)
979 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
981 dev_dbg(&intf->dev, "forced unbind\n");
982 usb_driver_release_interface(driver, intf);
984 /* Mark the interface for later rebinding */
985 intf->needs_binding = 1;
988 /* Delayed forced unbinding of a USB interface driver and scan
991 * The caller must hold @intf's device's lock, but not its pm_mutex
992 * and not @intf->dev.sem.
994 * Note: Rebinds will be skipped if a system sleep transition is in
995 * progress and the PM "complete" callback hasn't occurred yet.
997 void usb_rebind_intf(struct usb_interface *intf)
1001 /* Delayed unbind of an existing driver */
1002 if (intf->dev.driver)
1003 usb_forced_unbind_intf(intf);
1005 /* Try to rebind the interface */
1006 if (!intf->dev.power.is_prepared) {
1007 intf->needs_binding = 0;
1008 rc = device_attach(&intf->dev);
1010 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
1016 /* Unbind drivers for @udev's interfaces that don't support suspend/resume
1017 * There is no check for reset_resume here because it can be determined
1018 * only during resume whether reset_resume is needed.
1020 * The caller must hold @udev's device lock.
1022 static void unbind_no_pm_drivers_interfaces(struct usb_device *udev)
1024 struct usb_host_config *config;
1026 struct usb_interface *intf;
1027 struct usb_driver *drv;
1029 config = udev->actconfig;
1031 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1032 intf = config->interface[i];
1034 if (intf->dev.driver) {
1035 drv = to_usb_driver(intf->dev.driver);
1036 if (!drv->suspend || !drv->resume)
1037 usb_forced_unbind_intf(intf);
1043 /* Unbind drivers for @udev's interfaces that failed to support reset-resume.
1044 * These interfaces have the needs_binding flag set by usb_resume_interface().
1046 * The caller must hold @udev's device lock.
1048 static void unbind_no_reset_resume_drivers_interfaces(struct usb_device *udev)
1050 struct usb_host_config *config;
1052 struct usb_interface *intf;
1054 config = udev->actconfig;
1056 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1057 intf = config->interface[i];
1058 if (intf->dev.driver && intf->needs_binding)
1059 usb_forced_unbind_intf(intf);
1064 static void do_rebind_interfaces(struct usb_device *udev)
1066 struct usb_host_config *config;
1068 struct usb_interface *intf;
1070 config = udev->actconfig;
1072 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1073 intf = config->interface[i];
1074 if (intf->needs_binding)
1075 usb_rebind_intf(intf);
1080 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
1082 struct usb_device_driver *udriver;
1085 if (udev->state == USB_STATE_NOTATTACHED ||
1086 udev->state == USB_STATE_SUSPENDED)
1089 /* For devices that don't have a driver, we do a generic suspend. */
1090 if (udev->dev.driver)
1091 udriver = to_usb_device_driver(udev->dev.driver);
1093 udev->do_remote_wakeup = 0;
1094 udriver = &usb_generic_driver;
1096 status = udriver->suspend(udev, msg);
1099 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1103 static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1105 struct usb_device_driver *udriver;
1108 if (udev->state == USB_STATE_NOTATTACHED)
1111 /* Can't resume it if it doesn't have a driver. */
1112 if (udev->dev.driver == NULL) {
1117 /* Non-root devices on a full/low-speed bus must wait for their
1118 * companion high-speed root hub, in case a handoff is needed.
1120 if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion)
1121 device_pm_wait_for_dev(&udev->dev,
1122 &udev->bus->hs_companion->root_hub->dev);
1124 if (udev->quirks & USB_QUIRK_RESET_RESUME)
1125 udev->reset_resume = 1;
1127 udriver = to_usb_device_driver(udev->dev.driver);
1128 status = udriver->resume(udev, msg);
1131 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1135 static int usb_suspend_interface(struct usb_device *udev,
1136 struct usb_interface *intf, pm_message_t msg)
1138 struct usb_driver *driver;
1141 if (udev->state == USB_STATE_NOTATTACHED ||
1142 intf->condition == USB_INTERFACE_UNBOUND)
1144 driver = to_usb_driver(intf->dev.driver);
1146 /* at this time we know the driver supports suspend */
1147 status = driver->suspend(intf, msg);
1148 if (status && !PMSG_IS_AUTO(msg))
1149 dev_err(&intf->dev, "suspend error %d\n", status);
1152 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1156 static int usb_resume_interface(struct usb_device *udev,
1157 struct usb_interface *intf, pm_message_t msg, int reset_resume)
1159 struct usb_driver *driver;
1162 if (udev->state == USB_STATE_NOTATTACHED)
1165 /* Don't let autoresume interfere with unbinding */
1166 if (intf->condition == USB_INTERFACE_UNBINDING)
1169 /* Can't resume it if it doesn't have a driver. */
1170 if (intf->condition == USB_INTERFACE_UNBOUND) {
1172 /* Carry out a deferred switch to altsetting 0 */
1173 if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1174 usb_set_interface(udev, intf->altsetting[0].
1175 desc.bInterfaceNumber, 0);
1176 intf->needs_altsetting0 = 0;
1181 /* Don't resume if the interface is marked for rebinding */
1182 if (intf->needs_binding)
1184 driver = to_usb_driver(intf->dev.driver);
1187 if (driver->reset_resume) {
1188 status = driver->reset_resume(intf);
1190 dev_err(&intf->dev, "%s error %d\n",
1191 "reset_resume", status);
1193 intf->needs_binding = 1;
1194 dev_warn(&intf->dev, "no %s for driver %s?\n",
1195 "reset_resume", driver->name);
1198 status = driver->resume(intf);
1200 dev_err(&intf->dev, "resume error %d\n", status);
1204 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1206 /* Later we will unbind the driver and/or reprobe, if necessary */
1211 * usb_suspend_both - suspend a USB device and its interfaces
1212 * @udev: the usb_device to suspend
1213 * @msg: Power Management message describing this state transition
1215 * This is the central routine for suspending USB devices. It calls the
1216 * suspend methods for all the interface drivers in @udev and then calls
1217 * the suspend method for @udev itself. If an error occurs at any stage,
1218 * all the interfaces which were suspended are resumed so that they remain
1219 * in the same state as the device.
1221 * Autosuspend requests originating from a child device or an interface
1222 * driver may be made without the protection of @udev's device lock, but
1223 * all other suspend calls will hold the lock. Usbcore will insure that
1224 * method calls do not arrive during bind, unbind, or reset operations.
1225 * However drivers must be prepared to handle suspend calls arriving at
1226 * unpredictable times.
1228 * This routine can run only in process context.
1230 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1234 struct usb_interface *intf;
1236 if (udev->state == USB_STATE_NOTATTACHED ||
1237 udev->state == USB_STATE_SUSPENDED)
1240 /* Suspend all the interfaces and then udev itself */
1241 if (udev->actconfig) {
1242 n = udev->actconfig->desc.bNumInterfaces;
1243 for (i = n - 1; i >= 0; --i) {
1244 intf = udev->actconfig->interface[i];
1245 status = usb_suspend_interface(udev, intf, msg);
1247 /* Ignore errors during system sleep transitions */
1248 if (!PMSG_IS_AUTO(msg))
1255 status = usb_suspend_device(udev, msg);
1258 * Ignore errors from non-root-hub devices during
1259 * system sleep transitions. For the most part,
1260 * these devices should go to low power anyway when
1261 * the entire bus is suspended.
1263 if (udev->parent && !PMSG_IS_AUTO(msg))
1267 /* If the suspend failed, resume interfaces that did get suspended */
1269 msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1271 intf = udev->actconfig->interface[i];
1272 usb_resume_interface(udev, intf, msg, 0);
1275 /* If the suspend succeeded then prevent any more URB submissions
1276 * and flush any outstanding URBs.
1279 udev->can_submit = 0;
1280 for (i = 0; i < 16; ++i) {
1281 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1282 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1287 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1292 * usb_resume_both - resume a USB device and its interfaces
1293 * @udev: the usb_device to resume
1294 * @msg: Power Management message describing this state transition
1296 * This is the central routine for resuming USB devices. It calls the
1297 * the resume method for @udev and then calls the resume methods for all
1298 * the interface drivers in @udev.
1300 * Autoresume requests originating from a child device or an interface
1301 * driver may be made without the protection of @udev's device lock, but
1302 * all other resume calls will hold the lock. Usbcore will insure that
1303 * method calls do not arrive during bind, unbind, or reset operations.
1304 * However drivers must be prepared to handle resume calls arriving at
1305 * unpredictable times.
1307 * This routine can run only in process context.
1309 static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1313 struct usb_interface *intf;
1315 if (udev->state == USB_STATE_NOTATTACHED) {
1319 udev->can_submit = 1;
1321 /* Resume the device */
1322 if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume)
1323 status = usb_resume_device(udev, msg);
1325 /* Resume the interfaces */
1326 if (status == 0 && udev->actconfig) {
1327 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1328 intf = udev->actconfig->interface[i];
1329 usb_resume_interface(udev, intf, msg,
1330 udev->reset_resume);
1333 usb_mark_last_busy(udev);
1336 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1338 udev->reset_resume = 0;
1342 static void choose_wakeup(struct usb_device *udev, pm_message_t msg)
1346 /* Remote wakeup is needed only when we actually go to sleep.
1347 * For things like FREEZE and QUIESCE, if the device is already
1348 * autosuspended then its current wakeup setting is okay.
1350 if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
1351 if (udev->state != USB_STATE_SUSPENDED)
1352 udev->do_remote_wakeup = 0;
1356 /* Enable remote wakeup if it is allowed, even if no interface drivers
1359 w = device_may_wakeup(&udev->dev);
1361 /* If the device is autosuspended with the wrong wakeup setting,
1362 * autoresume now so the setting can be changed.
1364 if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup)
1365 pm_runtime_resume(&udev->dev);
1366 udev->do_remote_wakeup = w;
1369 /* The device lock is held by the PM core */
1370 int usb_suspend(struct device *dev, pm_message_t msg)
1372 struct usb_device *udev = to_usb_device(dev);
1374 unbind_no_pm_drivers_interfaces(udev);
1376 /* From now on we are sure all drivers support suspend/resume
1377 * but not necessarily reset_resume()
1378 * so we may still need to unbind and rebind upon resume
1380 choose_wakeup(udev, msg);
1381 return usb_suspend_both(udev, msg);
1384 /* The device lock is held by the PM core */
1385 int usb_resume_complete(struct device *dev)
1387 struct usb_device *udev = to_usb_device(dev);
1389 /* For PM complete calls, all we do is rebind interfaces
1390 * whose needs_binding flag is set
1392 if (udev->state != USB_STATE_NOTATTACHED)
1393 do_rebind_interfaces(udev);
1397 /* The device lock is held by the PM core */
1398 int usb_resume(struct device *dev, pm_message_t msg)
1400 struct usb_device *udev = to_usb_device(dev);
1403 /* For all calls, take the device back to full power and
1404 * tell the PM core in case it was autosuspended previously.
1405 * Unbind the interfaces that will need rebinding later,
1406 * because they fail to support reset_resume.
1407 * (This can't be done in usb_resume_interface()
1408 * above because it doesn't own the right set of locks.)
1410 status = usb_resume_both(udev, msg);
1412 pm_runtime_disable(dev);
1413 pm_runtime_set_active(dev);
1414 pm_runtime_enable(dev);
1415 unbind_no_reset_resume_drivers_interfaces(udev);
1418 /* Avoid PM error messages for devices disconnected while suspended
1419 * as we'll display regular disconnect messages just a bit later.
1421 if (status == -ENODEV || status == -ESHUTDOWN)
1426 #endif /* CONFIG_PM */
1428 #ifdef CONFIG_USB_SUSPEND
1431 * usb_enable_autosuspend - allow a USB device to be autosuspended
1432 * @udev: the USB device which may be autosuspended
1434 * This routine allows @udev to be autosuspended. An autosuspend won't
1435 * take place until the autosuspend_delay has elapsed and all the other
1436 * necessary conditions are satisfied.
1438 * The caller must hold @udev's device lock.
1440 void usb_enable_autosuspend(struct usb_device *udev)
1442 pm_runtime_allow(&udev->dev);
1444 EXPORT_SYMBOL_GPL(usb_enable_autosuspend);
1447 * usb_disable_autosuspend - prevent a USB device from being autosuspended
1448 * @udev: the USB device which may not be autosuspended
1450 * This routine prevents @udev from being autosuspended and wakes it up
1451 * if it is already autosuspended.
1453 * The caller must hold @udev's device lock.
1455 void usb_disable_autosuspend(struct usb_device *udev)
1457 pm_runtime_forbid(&udev->dev);
1459 EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
1462 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1463 * @udev: the usb_device to autosuspend
1465 * This routine should be called when a core subsystem is finished using
1466 * @udev and wants to allow it to autosuspend. Examples would be when
1467 * @udev's device file in usbfs is closed or after a configuration change.
1469 * @udev's usage counter is decremented; if it drops to 0 and all the
1470 * interfaces are inactive then a delayed autosuspend will be attempted.
1471 * The attempt may fail (see autosuspend_check()).
1473 * The caller must hold @udev's device lock.
1475 * This routine can run only in process context.
1477 void usb_autosuspend_device(struct usb_device *udev)
1481 usb_mark_last_busy(udev);
1482 status = pm_runtime_put_sync_autosuspend(&udev->dev);
1483 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1484 __func__, atomic_read(&udev->dev.power.usage_count),
1489 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1490 * @udev: the usb_device to autoresume
1492 * This routine should be called when a core subsystem wants to use @udev
1493 * and needs to guarantee that it is not suspended. No autosuspend will
1494 * occur until usb_autosuspend_device() is called. (Note that this will
1495 * not prevent suspend events originating in the PM core.) Examples would
1496 * be when @udev's device file in usbfs is opened or when a remote-wakeup
1497 * request is received.
1499 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1500 * However if the autoresume fails then the usage counter is re-decremented.
1502 * The caller must hold @udev's device lock.
1504 * This routine can run only in process context.
1506 int usb_autoresume_device(struct usb_device *udev)
1510 status = pm_runtime_get_sync(&udev->dev);
1512 pm_runtime_put_sync(&udev->dev);
1513 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1514 __func__, atomic_read(&udev->dev.power.usage_count),
1522 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1523 * @intf: the usb_interface whose counter should be decremented
1525 * This routine should be called by an interface driver when it is
1526 * finished using @intf and wants to allow it to autosuspend. A typical
1527 * example would be a character-device driver when its device file is
1530 * The routine decrements @intf's usage counter. When the counter reaches
1531 * 0, a delayed autosuspend request for @intf's device is attempted. The
1532 * attempt may fail (see autosuspend_check()).
1534 * This routine can run only in process context.
1536 void usb_autopm_put_interface(struct usb_interface *intf)
1538 struct usb_device *udev = interface_to_usbdev(intf);
1541 usb_mark_last_busy(udev);
1542 atomic_dec(&intf->pm_usage_cnt);
1543 status = pm_runtime_put_sync(&intf->dev);
1544 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1545 __func__, atomic_read(&intf->dev.power.usage_count),
1548 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1551 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1552 * @intf: the usb_interface whose counter should be decremented
1554 * This routine does much the same thing as usb_autopm_put_interface():
1555 * It decrements @intf's usage counter and schedules a delayed
1556 * autosuspend request if the counter is <= 0. The difference is that it
1557 * does not perform any synchronization; callers should hold a private
1558 * lock and handle all synchronization issues themselves.
1560 * Typically a driver would call this routine during an URB's completion
1561 * handler, if no more URBs were pending.
1563 * This routine can run in atomic context.
1565 void usb_autopm_put_interface_async(struct usb_interface *intf)
1567 struct usb_device *udev = interface_to_usbdev(intf);
1570 usb_mark_last_busy(udev);
1571 atomic_dec(&intf->pm_usage_cnt);
1572 status = pm_runtime_put(&intf->dev);
1573 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1574 __func__, atomic_read(&intf->dev.power.usage_count),
1577 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1580 * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
1581 * @intf: the usb_interface whose counter should be decremented
1583 * This routine decrements @intf's usage counter but does not carry out an
1586 * This routine can run in atomic context.
1588 void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
1590 struct usb_device *udev = interface_to_usbdev(intf);
1592 usb_mark_last_busy(udev);
1593 atomic_dec(&intf->pm_usage_cnt);
1594 pm_runtime_put_noidle(&intf->dev);
1596 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
1599 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1600 * @intf: the usb_interface whose counter should be incremented
1602 * This routine should be called by an interface driver when it wants to
1603 * use @intf and needs to guarantee that it is not suspended. In addition,
1604 * the routine prevents @intf from being autosuspended subsequently. (Note
1605 * that this will not prevent suspend events originating in the PM core.)
1606 * This prevention will persist until usb_autopm_put_interface() is called
1607 * or @intf is unbound. A typical example would be a character-device
1608 * driver when its device file is opened.
1610 * @intf's usage counter is incremented to prevent subsequent autosuspends.
1611 * However if the autoresume fails then the counter is re-decremented.
1613 * This routine can run only in process context.
1615 int usb_autopm_get_interface(struct usb_interface *intf)
1619 status = pm_runtime_get_sync(&intf->dev);
1621 pm_runtime_put_sync(&intf->dev);
1623 atomic_inc(&intf->pm_usage_cnt);
1624 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1625 __func__, atomic_read(&intf->dev.power.usage_count),
1631 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1634 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1635 * @intf: the usb_interface whose counter should be incremented
1637 * This routine does much the same thing as
1638 * usb_autopm_get_interface(): It increments @intf's usage counter and
1639 * queues an autoresume request if the device is suspended. The
1640 * differences are that it does not perform any synchronization (callers
1641 * should hold a private lock and handle all synchronization issues
1642 * themselves), and it does not autoresume the device directly (it only
1643 * queues a request). After a successful call, the device may not yet be
1646 * This routine can run in atomic context.
1648 int usb_autopm_get_interface_async(struct usb_interface *intf)
1652 status = pm_runtime_get(&intf->dev);
1653 if (status < 0 && status != -EINPROGRESS)
1654 pm_runtime_put_noidle(&intf->dev);
1656 atomic_inc(&intf->pm_usage_cnt);
1657 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1658 __func__, atomic_read(&intf->dev.power.usage_count),
1660 if (status > 0 || status == -EINPROGRESS)
1664 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1667 * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
1668 * @intf: the usb_interface whose counter should be incremented
1670 * This routine increments @intf's usage counter but does not carry out an
1673 * This routine can run in atomic context.
1675 void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
1677 struct usb_device *udev = interface_to_usbdev(intf);
1679 usb_mark_last_busy(udev);
1680 atomic_inc(&intf->pm_usage_cnt);
1681 pm_runtime_get_noresume(&intf->dev);
1683 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
1685 /* Internal routine to check whether we may autosuspend a device. */
1686 static int autosuspend_check(struct usb_device *udev)
1689 struct usb_interface *intf;
1691 /* Fail if autosuspend is disabled, or any interfaces are in use, or
1692 * any interface drivers require remote wakeup but it isn't available.
1695 if (udev->actconfig) {
1696 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1697 intf = udev->actconfig->interface[i];
1699 /* We don't need to check interfaces that are
1700 * disabled for runtime PM. Either they are unbound
1701 * or else their drivers don't support autosuspend
1702 * and so they are permanently active.
1704 if (intf->dev.power.disable_depth)
1706 if (atomic_read(&intf->dev.power.usage_count) > 0)
1708 w |= intf->needs_remote_wakeup;
1710 /* Don't allow autosuspend if the device will need
1711 * a reset-resume and any of its interface drivers
1712 * doesn't include support or needs remote wakeup.
1714 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1715 struct usb_driver *driver;
1717 driver = to_usb_driver(intf->dev.driver);
1718 if (!driver->reset_resume ||
1719 intf->needs_remote_wakeup)
1724 if (w && !device_can_wakeup(&udev->dev)) {
1725 dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
1728 udev->do_remote_wakeup = w;
1732 int usb_runtime_suspend(struct device *dev)
1734 struct usb_device *udev = to_usb_device(dev);
1737 /* A USB device can be suspended if it passes the various autosuspend
1738 * checks. Runtime suspend for a USB device means suspending all the
1739 * interfaces and then the device itself.
1741 if (autosuspend_check(udev) != 0)
1744 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1746 /* Allow a retry if autosuspend failed temporarily */
1747 if (status == -EAGAIN || status == -EBUSY)
1748 usb_mark_last_busy(udev);
1750 /* The PM core reacts badly unless the return code is 0,
1751 * -EAGAIN, or -EBUSY, so always return -EBUSY on an error.
1758 int usb_runtime_resume(struct device *dev)
1760 struct usb_device *udev = to_usb_device(dev);
1763 /* Runtime resume for a USB device means resuming both the device
1764 * and all its interfaces.
1766 status = usb_resume_both(udev, PMSG_AUTO_RESUME);
1770 int usb_runtime_idle(struct device *dev)
1772 struct usb_device *udev = to_usb_device(dev);
1774 /* An idle USB device can be suspended if it passes the various
1775 * autosuspend checks.
1777 if (autosuspend_check(udev) == 0)
1778 pm_runtime_autosuspend(dev);
1782 int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
1784 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1787 if (hcd->driver->set_usb2_hw_lpm) {
1788 ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable);
1790 udev->usb2_hw_lpm_enabled = enable;
1796 #endif /* CONFIG_USB_SUSPEND */
1798 struct bus_type usb_bus_type = {
1800 .match = usb_device_match,
1801 .uevent = usb_uevent,