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>
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 const struct usb_device_id *id_table,
41 struct device_driver *driver,
42 const char *buf, size_t count)
44 struct usb_dynid *dynid;
47 unsigned int bInterfaceClass = 0;
48 u32 refVendor, refProduct;
52 fields = sscanf(buf, "%x %x %x %x %x", &idVendor, &idProduct,
53 &bInterfaceClass, &refVendor, &refProduct);
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;
65 if (fields > 2 && bInterfaceClass) {
66 if (bInterfaceClass > 255) {
71 dynid->id.bInterfaceClass = (u8)bInterfaceClass;
72 dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
76 const struct usb_device_id *id = id_table;
83 for (; id->match_flags; id++)
84 if (id->idVendor == refVendor && id->idProduct == refProduct)
87 if (id->match_flags) {
88 dynid->id.driver_info = id->driver_info;
95 spin_lock(&dynids->lock);
96 list_add_tail(&dynid->node, &dynids->list);
97 spin_unlock(&dynids->lock);
99 retval = driver_attach(driver);
109 EXPORT_SYMBOL_GPL(usb_store_new_id);
111 ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf)
113 struct usb_dynid *dynid;
116 list_for_each_entry(dynid, &dynids->list, node)
117 if (dynid->id.bInterfaceClass != 0)
118 count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x %02x\n",
119 dynid->id.idVendor, dynid->id.idProduct,
120 dynid->id.bInterfaceClass);
122 count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x\n",
123 dynid->id.idVendor, dynid->id.idProduct);
126 EXPORT_SYMBOL_GPL(usb_show_dynids);
128 static ssize_t new_id_show(struct device_driver *driver, char *buf)
130 struct usb_driver *usb_drv = to_usb_driver(driver);
132 return usb_show_dynids(&usb_drv->dynids, buf);
135 static ssize_t new_id_store(struct device_driver *driver,
136 const char *buf, size_t count)
138 struct usb_driver *usb_drv = to_usb_driver(driver);
140 return usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, driver, buf, count);
142 static DRIVER_ATTR_RW(new_id);
145 * Remove a USB device ID from this driver
147 static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
150 struct usb_dynid *dynid, *n;
151 struct usb_driver *usb_driver = to_usb_driver(driver);
156 fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
160 spin_lock(&usb_driver->dynids.lock);
161 list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) {
162 struct usb_device_id *id = &dynid->id;
163 if ((id->idVendor == idVendor) &&
164 (id->idProduct == idProduct)) {
165 list_del(&dynid->node);
170 spin_unlock(&usb_driver->dynids.lock);
174 static ssize_t remove_id_show(struct device_driver *driver, char *buf)
176 return new_id_show(driver, buf);
178 static DRIVER_ATTR_RW(remove_id);
180 static int usb_create_newid_files(struct usb_driver *usb_drv)
184 if (usb_drv->no_dynamic_id)
187 if (usb_drv->probe != NULL) {
188 error = driver_create_file(&usb_drv->drvwrap.driver,
189 &driver_attr_new_id);
191 error = driver_create_file(&usb_drv->drvwrap.driver,
192 &driver_attr_remove_id);
194 driver_remove_file(&usb_drv->drvwrap.driver,
195 &driver_attr_new_id);
202 static void usb_remove_newid_files(struct usb_driver *usb_drv)
204 if (usb_drv->no_dynamic_id)
207 if (usb_drv->probe != NULL) {
208 driver_remove_file(&usb_drv->drvwrap.driver,
209 &driver_attr_remove_id);
210 driver_remove_file(&usb_drv->drvwrap.driver,
211 &driver_attr_new_id);
215 static void usb_free_dynids(struct usb_driver *usb_drv)
217 struct usb_dynid *dynid, *n;
219 spin_lock(&usb_drv->dynids.lock);
220 list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
221 list_del(&dynid->node);
224 spin_unlock(&usb_drv->dynids.lock);
227 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
228 struct usb_driver *drv)
230 struct usb_dynid *dynid;
232 spin_lock(&drv->dynids.lock);
233 list_for_each_entry(dynid, &drv->dynids.list, node) {
234 if (usb_match_one_id(intf, &dynid->id)) {
235 spin_unlock(&drv->dynids.lock);
239 spin_unlock(&drv->dynids.lock);
244 /* called from driver core with dev locked */
245 static int usb_probe_device(struct device *dev)
247 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
248 struct usb_device *udev = to_usb_device(dev);
251 dev_dbg(dev, "%s\n", __func__);
253 /* TODO: Add real matching code */
255 /* The device should always appear to be in use
256 * unless the driver supports autosuspend.
258 if (!udriver->supports_autosuspend)
259 error = usb_autoresume_device(udev);
262 error = udriver->probe(udev);
266 /* called from driver core with dev locked */
267 static int usb_unbind_device(struct device *dev)
269 struct usb_device *udev = to_usb_device(dev);
270 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
272 udriver->disconnect(udev);
273 if (!udriver->supports_autosuspend)
274 usb_autosuspend_device(udev);
279 * Cancel any pending scheduled resets
281 * [see usb_queue_reset_device()]
283 * Called after unconfiguring / when releasing interfaces. See
284 * comments in __usb_queue_reset_device() regarding
285 * udev->reset_running.
287 static void usb_cancel_queued_reset(struct usb_interface *iface)
289 if (iface->reset_running == 0)
290 cancel_work_sync(&iface->reset_ws);
293 /* called from driver core with dev locked */
294 static int usb_probe_interface(struct device *dev)
296 struct usb_driver *driver = to_usb_driver(dev->driver);
297 struct usb_interface *intf = to_usb_interface(dev);
298 struct usb_device *udev = interface_to_usbdev(intf);
299 const struct usb_device_id *id;
301 int lpm_disable_error;
303 dev_dbg(dev, "%s\n", __func__);
305 intf->needs_binding = 0;
307 if (usb_device_is_owned(udev))
310 if (udev->authorized == 0) {
311 dev_err(&intf->dev, "Device is not authorized for usage\n");
315 id = usb_match_dynamic_id(intf, driver);
317 id = usb_match_id(intf, driver->id_table);
321 dev_dbg(dev, "%s - got id\n", __func__);
323 error = usb_autoresume_device(udev);
327 intf->condition = USB_INTERFACE_BINDING;
329 /* Probed interfaces are initially active. They are
330 * runtime-PM-enabled only if the driver has autosuspend support.
331 * They are sensitive to their children's power states.
333 pm_runtime_set_active(dev);
334 pm_suspend_ignore_children(dev, false);
335 if (driver->supports_autosuspend)
336 pm_runtime_enable(dev);
338 /* If the new driver doesn't allow hub-initiated LPM, and we can't
339 * disable hub-initiated LPM, then fail the probe.
341 * Otherwise, leaving LPM enabled should be harmless, because the
342 * endpoint intervals should remain the same, and the U1/U2 timeouts
343 * should remain the same.
345 * If we need to install alt setting 0 before probe, or another alt
346 * setting during probe, that should also be fine. usb_set_interface()
347 * will attempt to disable LPM, and fail if it can't disable it.
349 lpm_disable_error = usb_unlocked_disable_lpm(udev);
350 if (lpm_disable_error && driver->disable_hub_initiated_lpm) {
351 dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n.",
352 __func__, driver->name);
353 error = lpm_disable_error;
357 /* Carry out a deferred switch to altsetting 0 */
358 if (intf->needs_altsetting0) {
359 error = usb_set_interface(udev, intf->altsetting[0].
360 desc.bInterfaceNumber, 0);
363 intf->needs_altsetting0 = 0;
366 error = driver->probe(intf, id);
370 intf->condition = USB_INTERFACE_BOUND;
372 /* If the LPM disable succeeded, balance the ref counts. */
373 if (!lpm_disable_error)
374 usb_unlocked_enable_lpm(udev);
376 usb_autosuspend_device(udev);
380 usb_set_intfdata(intf, NULL);
381 intf->needs_remote_wakeup = 0;
382 intf->condition = USB_INTERFACE_UNBOUND;
383 usb_cancel_queued_reset(intf);
385 /* If the LPM disable succeeded, balance the ref counts. */
386 if (!lpm_disable_error)
387 usb_unlocked_enable_lpm(udev);
389 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
390 if (driver->supports_autosuspend)
391 pm_runtime_disable(dev);
392 pm_runtime_set_suspended(dev);
394 usb_autosuspend_device(udev);
398 /* called from driver core with dev locked */
399 static int usb_unbind_interface(struct device *dev)
401 struct usb_driver *driver = to_usb_driver(dev->driver);
402 struct usb_interface *intf = to_usb_interface(dev);
403 struct usb_host_endpoint *ep, **eps = NULL;
404 struct usb_device *udev;
405 int i, j, error, r, lpm_disable_error;
407 intf->condition = USB_INTERFACE_UNBINDING;
409 /* Autoresume for set_interface call below */
410 udev = interface_to_usbdev(intf);
411 error = usb_autoresume_device(udev);
413 /* Hub-initiated LPM policy may change, so attempt to disable LPM until
414 * the driver is unbound. If LPM isn't disabled, that's fine because it
415 * wouldn't be enabled unless all the bound interfaces supported
418 lpm_disable_error = usb_unlocked_disable_lpm(udev);
420 /* Terminate all URBs for this interface unless the driver
421 * supports "soft" unbinding.
423 if (!driver->soft_unbind)
424 usb_disable_interface(udev, intf, false);
426 driver->disconnect(intf);
427 usb_cancel_queued_reset(intf);
430 for (i = 0, j = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
431 ep = &intf->cur_altsetting->endpoint[i];
432 if (ep->streams == 0)
435 eps = kmalloc(USB_MAXENDPOINTS * sizeof(void *),
438 dev_warn(dev, "oom, leaking streams\n");
445 usb_free_streams(intf, eps, j, GFP_KERNEL);
449 /* Reset other interface state.
450 * We cannot do a Set-Interface if the device is suspended or
451 * if it is prepared for a system sleep (since installing a new
452 * altsetting means creating new endpoint device entries).
453 * When either of these happens, defer the Set-Interface.
455 if (intf->cur_altsetting->desc.bAlternateSetting == 0) {
456 /* Already in altsetting 0 so skip Set-Interface.
457 * Just re-enable it without affecting the endpoint toggles.
459 usb_enable_interface(udev, intf, false);
460 } else if (!error && !intf->dev.power.is_prepared) {
461 r = usb_set_interface(udev, intf->altsetting[0].
462 desc.bInterfaceNumber, 0);
464 intf->needs_altsetting0 = 1;
466 intf->needs_altsetting0 = 1;
468 usb_set_intfdata(intf, NULL);
470 intf->condition = USB_INTERFACE_UNBOUND;
471 intf->needs_remote_wakeup = 0;
473 /* Attempt to re-enable USB3 LPM, if the disable succeeded. */
474 if (!lpm_disable_error)
475 usb_unlocked_enable_lpm(udev);
477 /* Unbound interfaces are always runtime-PM-disabled and -suspended */
478 if (driver->supports_autosuspend)
479 pm_runtime_disable(dev);
480 pm_runtime_set_suspended(dev);
482 /* Undo any residual pm_autopm_get_interface_* calls */
483 for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r)
484 usb_autopm_put_interface_no_suspend(intf);
485 atomic_set(&intf->pm_usage_cnt, 0);
488 usb_autosuspend_device(udev);
494 * usb_driver_claim_interface - bind a driver to an interface
495 * @driver: the driver to be bound
496 * @iface: the interface to which it will be bound; must be in the
497 * usb device's active configuration
498 * @priv: driver data associated with that interface
500 * This is used by usb device drivers that need to claim more than one
501 * interface on a device when probing (audio and acm are current examples).
502 * No device driver should directly modify internal usb_interface or
503 * usb_device structure members.
505 * Few drivers should need to use this routine, since the most natural
506 * way to bind to an interface is to return the private data from
507 * the driver's probe() method.
509 * Callers must own the device lock, so driver probe() entries don't need
510 * extra locking, but other call contexts may need to explicitly claim that
513 * Return: 0 on success.
515 int usb_driver_claim_interface(struct usb_driver *driver,
516 struct usb_interface *iface, void *priv)
518 struct device *dev = &iface->dev;
519 struct usb_device *udev;
521 int lpm_disable_error;
526 udev = interface_to_usbdev(iface);
528 dev->driver = &driver->drvwrap.driver;
529 usb_set_intfdata(iface, priv);
530 iface->needs_binding = 0;
532 iface->condition = USB_INTERFACE_BOUND;
534 /* Disable LPM until this driver is bound. */
535 lpm_disable_error = usb_unlocked_disable_lpm(udev);
536 if (lpm_disable_error && driver->disable_hub_initiated_lpm) {
537 dev_err(&iface->dev, "%s Failed to disable LPM for driver %s\n.",
538 __func__, driver->name);
542 /* Claimed interfaces are initially inactive (suspended) and
543 * runtime-PM-enabled, but only if the driver has autosuspend
544 * support. Otherwise they are marked active, to prevent the
545 * device from being autosuspended, but left disabled. In either
546 * case they are sensitive to their children's power states.
548 pm_suspend_ignore_children(dev, false);
549 if (driver->supports_autosuspend)
550 pm_runtime_enable(dev);
552 pm_runtime_set_active(dev);
554 /* if interface was already added, bind now; else let
555 * the future device_add() bind it, bypassing probe()
557 if (device_is_registered(dev))
558 retval = device_bind_driver(dev);
560 /* Attempt to re-enable USB3 LPM, if the disable was successful. */
561 if (!lpm_disable_error)
562 usb_unlocked_enable_lpm(udev);
566 EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
569 * usb_driver_release_interface - unbind a driver from an interface
570 * @driver: the driver to be unbound
571 * @iface: the interface from which it will be unbound
573 * This can be used by drivers to release an interface without waiting
574 * for their disconnect() methods to be called. In typical cases this
575 * also causes the driver disconnect() method to be called.
577 * This call is synchronous, and may not be used in an interrupt context.
578 * Callers must own the device lock, so driver disconnect() entries don't
579 * need extra locking, but other call contexts may need to explicitly claim
582 void usb_driver_release_interface(struct usb_driver *driver,
583 struct usb_interface *iface)
585 struct device *dev = &iface->dev;
587 /* this should never happen, don't release something that's not ours */
588 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
591 /* don't release from within disconnect() */
592 if (iface->condition != USB_INTERFACE_BOUND)
594 iface->condition = USB_INTERFACE_UNBINDING;
596 /* Release via the driver core only if the interface
597 * has already been registered
599 if (device_is_registered(dev)) {
600 device_release_driver(dev);
603 usb_unbind_interface(dev);
608 EXPORT_SYMBOL_GPL(usb_driver_release_interface);
610 /* returns 0 if no match, 1 if match */
611 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
613 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
614 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
617 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
618 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
621 /* No need to test id->bcdDevice_lo != 0, since 0 is never
622 greater than any unsigned number. */
623 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
624 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
627 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
628 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
631 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
632 (id->bDeviceClass != dev->descriptor.bDeviceClass))
635 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
636 (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
639 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
640 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
646 /* returns 0 if no match, 1 if match */
647 int usb_match_one_id_intf(struct usb_device *dev,
648 struct usb_host_interface *intf,
649 const struct usb_device_id *id)
651 /* The interface class, subclass, protocol and number should never be
652 * checked for a match if the device class is Vendor Specific,
653 * unless the match record specifies the Vendor ID. */
654 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
655 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
656 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
657 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
658 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
659 USB_DEVICE_ID_MATCH_INT_NUMBER)))
662 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
663 (id->bInterfaceClass != intf->desc.bInterfaceClass))
666 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
667 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
670 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
671 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
674 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
675 (id->bInterfaceNumber != intf->desc.bInterfaceNumber))
681 /* returns 0 if no match, 1 if match */
682 int usb_match_one_id(struct usb_interface *interface,
683 const struct usb_device_id *id)
685 struct usb_host_interface *intf;
686 struct usb_device *dev;
688 /* proc_connectinfo in devio.c may call us with id == NULL. */
692 intf = interface->cur_altsetting;
693 dev = interface_to_usbdev(interface);
695 if (!usb_match_device(dev, id))
698 return usb_match_one_id_intf(dev, intf, id);
700 EXPORT_SYMBOL_GPL(usb_match_one_id);
703 * usb_match_id - find first usb_device_id matching device or interface
704 * @interface: the interface of interest
705 * @id: array of usb_device_id structures, terminated by zero entry
707 * usb_match_id searches an array of usb_device_id's and returns
708 * the first one matching the device or interface, or null.
709 * This is used when binding (or rebinding) a driver to an interface.
710 * Most USB device drivers will use this indirectly, through the usb core,
711 * but some layered driver frameworks use it directly.
712 * These device tables are exported with MODULE_DEVICE_TABLE, through
713 * modutils, to support the driver loading functionality of USB hotplugging.
715 * Return: The first matching usb_device_id, or %NULL.
719 * The "match_flags" element in a usb_device_id controls which
720 * members are used. If the corresponding bit is set, the
721 * value in the device_id must match its corresponding member
722 * in the device or interface descriptor, or else the device_id
725 * "driver_info" is normally used only by device drivers,
726 * but you can create a wildcard "matches anything" usb_device_id
727 * as a driver's "modules.usbmap" entry if you provide an id with
728 * only a nonzero "driver_info" field. If you do this, the USB device
729 * driver's probe() routine should use additional intelligence to
730 * decide whether to bind to the specified interface.
732 * What Makes Good usb_device_id Tables:
734 * The match algorithm is very simple, so that intelligence in
735 * driver selection must come from smart driver id records.
736 * Unless you have good reasons to use another selection policy,
737 * provide match elements only in related groups, and order match
738 * specifiers from specific to general. Use the macros provided
739 * for that purpose if you can.
741 * The most specific match specifiers use device descriptor
742 * data. These are commonly used with product-specific matches;
743 * the USB_DEVICE macro lets you provide vendor and product IDs,
744 * and you can also match against ranges of product revisions.
745 * These are widely used for devices with application or vendor
746 * specific bDeviceClass values.
748 * Matches based on device class/subclass/protocol specifications
749 * are slightly more general; use the USB_DEVICE_INFO macro, or
750 * its siblings. These are used with single-function devices
751 * where bDeviceClass doesn't specify that each interface has
754 * Matches based on interface class/subclass/protocol are the
755 * most general; they let drivers bind to any interface on a
756 * multiple-function device. Use the USB_INTERFACE_INFO
757 * macro, or its siblings, to match class-per-interface style
758 * devices (as recorded in bInterfaceClass).
760 * Note that an entry created by USB_INTERFACE_INFO won't match
761 * any interface if the device class is set to Vendor-Specific.
762 * This is deliberate; according to the USB spec the meanings of
763 * the interface class/subclass/protocol for these devices are also
764 * vendor-specific, and hence matching against a standard product
765 * class wouldn't work anyway. If you really want to use an
766 * interface-based match for such a device, create a match record
767 * that also specifies the vendor ID. (Unforunately there isn't a
768 * standard macro for creating records like this.)
770 * Within those groups, remember that not all combinations are
771 * meaningful. For example, don't give a product version range
772 * without vendor and product IDs; or specify a protocol without
773 * its associated class and subclass.
775 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
776 const struct usb_device_id *id)
778 /* proc_connectinfo in devio.c may call us with id == NULL. */
782 /* It is important to check that id->driver_info is nonzero,
783 since an entry that is all zeroes except for a nonzero
784 id->driver_info is the way to create an entry that
785 indicates that the driver want to examine every
786 device and interface. */
787 for (; id->idVendor || id->idProduct || id->bDeviceClass ||
788 id->bInterfaceClass || id->driver_info; id++) {
789 if (usb_match_one_id(interface, id))
795 EXPORT_SYMBOL_GPL(usb_match_id);
797 static int usb_device_match(struct device *dev, struct device_driver *drv)
799 /* devices and interfaces are handled separately */
800 if (is_usb_device(dev)) {
802 /* interface drivers never match devices */
803 if (!is_usb_device_driver(drv))
806 /* TODO: Add real matching code */
809 } else if (is_usb_interface(dev)) {
810 struct usb_interface *intf;
811 struct usb_driver *usb_drv;
812 const struct usb_device_id *id;
814 /* device drivers never match interfaces */
815 if (is_usb_device_driver(drv))
818 intf = to_usb_interface(dev);
819 usb_drv = to_usb_driver(drv);
821 id = usb_match_id(intf, usb_drv->id_table);
825 id = usb_match_dynamic_id(intf, usb_drv);
833 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
835 struct usb_device *usb_dev;
837 if (is_usb_device(dev)) {
838 usb_dev = to_usb_device(dev);
839 } else if (is_usb_interface(dev)) {
840 struct usb_interface *intf = to_usb_interface(dev);
842 usb_dev = interface_to_usbdev(intf);
847 if (usb_dev->devnum < 0) {
848 /* driver is often null here; dev_dbg() would oops */
849 pr_debug("usb %s: already deleted?\n", dev_name(dev));
853 pr_debug("usb %s: bus removed?\n", dev_name(dev));
857 /* per-device configurations are common */
858 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
859 le16_to_cpu(usb_dev->descriptor.idVendor),
860 le16_to_cpu(usb_dev->descriptor.idProduct),
861 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
864 /* class-based driver binding models */
865 if (add_uevent_var(env, "TYPE=%d/%d/%d",
866 usb_dev->descriptor.bDeviceClass,
867 usb_dev->descriptor.bDeviceSubClass,
868 usb_dev->descriptor.bDeviceProtocol))
875 * usb_register_device_driver - register a USB device (not interface) driver
876 * @new_udriver: USB operations for the device driver
877 * @owner: module owner of this driver.
879 * Registers a USB device driver with the USB core. The list of
880 * unattached devices will be rescanned whenever a new driver is
881 * added, allowing the new driver to attach to any recognized devices.
883 * Return: A negative error code on failure and 0 on success.
885 int usb_register_device_driver(struct usb_device_driver *new_udriver,
886 struct module *owner)
893 new_udriver->drvwrap.for_devices = 1;
894 new_udriver->drvwrap.driver.name = new_udriver->name;
895 new_udriver->drvwrap.driver.bus = &usb_bus_type;
896 new_udriver->drvwrap.driver.probe = usb_probe_device;
897 new_udriver->drvwrap.driver.remove = usb_unbind_device;
898 new_udriver->drvwrap.driver.owner = owner;
900 retval = driver_register(&new_udriver->drvwrap.driver);
903 pr_info("%s: registered new device driver %s\n",
904 usbcore_name, new_udriver->name);
906 printk(KERN_ERR "%s: error %d registering device "
908 usbcore_name, retval, new_udriver->name);
912 EXPORT_SYMBOL_GPL(usb_register_device_driver);
915 * usb_deregister_device_driver - unregister a USB device (not interface) driver
916 * @udriver: USB operations of the device driver to unregister
917 * Context: must be able to sleep
919 * Unlinks the specified driver from the internal USB driver list.
921 void usb_deregister_device_driver(struct usb_device_driver *udriver)
923 pr_info("%s: deregistering device driver %s\n",
924 usbcore_name, udriver->name);
926 driver_unregister(&udriver->drvwrap.driver);
928 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
931 * usb_register_driver - register a USB interface driver
932 * @new_driver: USB operations for the interface driver
933 * @owner: module owner of this driver.
934 * @mod_name: module name string
936 * Registers a USB interface driver with the USB core. The list of
937 * unattached interfaces will be rescanned whenever a new driver is
938 * added, allowing the new driver to attach to any recognized interfaces.
940 * Return: A negative error code on failure and 0 on success.
942 * NOTE: if you want your driver to use the USB major number, you must call
943 * usb_register_dev() to enable that functionality. This function no longer
944 * takes care of that.
946 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
947 const char *mod_name)
954 new_driver->drvwrap.for_devices = 0;
955 new_driver->drvwrap.driver.name = new_driver->name;
956 new_driver->drvwrap.driver.bus = &usb_bus_type;
957 new_driver->drvwrap.driver.probe = usb_probe_interface;
958 new_driver->drvwrap.driver.remove = usb_unbind_interface;
959 new_driver->drvwrap.driver.owner = owner;
960 new_driver->drvwrap.driver.mod_name = mod_name;
961 spin_lock_init(&new_driver->dynids.lock);
962 INIT_LIST_HEAD(&new_driver->dynids.list);
964 retval = driver_register(&new_driver->drvwrap.driver);
968 retval = usb_create_newid_files(new_driver);
972 pr_info("%s: registered new interface driver %s\n",
973 usbcore_name, new_driver->name);
979 driver_unregister(&new_driver->drvwrap.driver);
981 printk(KERN_ERR "%s: error %d registering interface "
983 usbcore_name, retval, new_driver->name);
986 EXPORT_SYMBOL_GPL(usb_register_driver);
989 * usb_deregister - unregister a USB interface driver
990 * @driver: USB operations of the interface driver to unregister
991 * Context: must be able to sleep
993 * Unlinks the specified driver from the internal USB driver list.
995 * NOTE: If you called usb_register_dev(), you still need to call
996 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
997 * this * call will no longer do it for you.
999 void usb_deregister(struct usb_driver *driver)
1001 pr_info("%s: deregistering interface driver %s\n",
1002 usbcore_name, driver->name);
1004 usb_remove_newid_files(driver);
1005 driver_unregister(&driver->drvwrap.driver);
1006 usb_free_dynids(driver);
1008 EXPORT_SYMBOL_GPL(usb_deregister);
1010 /* Forced unbinding of a USB interface driver, either because
1011 * it doesn't support pre_reset/post_reset/reset_resume or
1012 * because it doesn't support suspend/resume.
1014 * The caller must hold @intf's device's lock, but not @intf's lock.
1016 void usb_forced_unbind_intf(struct usb_interface *intf)
1018 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
1020 dev_dbg(&intf->dev, "forced unbind\n");
1021 usb_driver_release_interface(driver, intf);
1023 /* Mark the interface for later rebinding */
1024 intf->needs_binding = 1;
1028 * Unbind drivers for @udev's marked interfaces. These interfaces have
1029 * the needs_binding flag set, for example by usb_resume_interface().
1031 * The caller must hold @udev's device lock.
1033 static void unbind_marked_interfaces(struct usb_device *udev)
1035 struct usb_host_config *config;
1037 struct usb_interface *intf;
1039 config = udev->actconfig;
1041 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1042 intf = config->interface[i];
1043 if (intf->dev.driver && intf->needs_binding)
1044 usb_forced_unbind_intf(intf);
1049 /* Delayed forced unbinding of a USB interface driver and scan
1052 * The caller must hold @intf's device's lock, but not @intf's lock.
1054 * Note: Rebinds will be skipped if a system sleep transition is in
1055 * progress and the PM "complete" callback hasn't occurred yet.
1057 static void usb_rebind_intf(struct usb_interface *intf)
1061 /* Delayed unbind of an existing driver */
1062 if (intf->dev.driver)
1063 usb_forced_unbind_intf(intf);
1065 /* Try to rebind the interface */
1066 if (!intf->dev.power.is_prepared) {
1067 intf->needs_binding = 0;
1068 rc = device_attach(&intf->dev);
1070 dev_warn(&intf->dev, "rebind failed: %d\n", rc);
1075 * Rebind drivers to @udev's marked interfaces. These interfaces have
1076 * the needs_binding flag set.
1078 * The caller must hold @udev's device lock.
1080 static void rebind_marked_interfaces(struct usb_device *udev)
1082 struct usb_host_config *config;
1084 struct usb_interface *intf;
1086 config = udev->actconfig;
1088 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1089 intf = config->interface[i];
1090 if (intf->needs_binding)
1091 usb_rebind_intf(intf);
1097 * Unbind all of @udev's marked interfaces and then rebind all of them.
1098 * This ordering is necessary because some drivers claim several interfaces
1099 * when they are first probed.
1101 * The caller must hold @udev's device lock.
1103 void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev)
1105 unbind_marked_interfaces(udev);
1106 rebind_marked_interfaces(udev);
1111 /* Unbind drivers for @udev's interfaces that don't support suspend/resume
1112 * There is no check for reset_resume here because it can be determined
1113 * only during resume whether reset_resume is needed.
1115 * The caller must hold @udev's device lock.
1117 static void unbind_no_pm_drivers_interfaces(struct usb_device *udev)
1119 struct usb_host_config *config;
1121 struct usb_interface *intf;
1122 struct usb_driver *drv;
1124 config = udev->actconfig;
1126 for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1127 intf = config->interface[i];
1129 if (intf->dev.driver) {
1130 drv = to_usb_driver(intf->dev.driver);
1131 if (!drv->suspend || !drv->resume)
1132 usb_forced_unbind_intf(intf);
1138 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
1140 struct usb_device_driver *udriver;
1143 if (udev->state == USB_STATE_NOTATTACHED ||
1144 udev->state == USB_STATE_SUSPENDED)
1147 /* For devices that don't have a driver, we do a generic suspend. */
1148 if (udev->dev.driver)
1149 udriver = to_usb_device_driver(udev->dev.driver);
1151 udev->do_remote_wakeup = 0;
1152 udriver = &usb_generic_driver;
1154 status = udriver->suspend(udev, msg);
1157 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1161 static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1163 struct usb_device_driver *udriver;
1166 if (udev->state == USB_STATE_NOTATTACHED)
1169 /* Can't resume it if it doesn't have a driver. */
1170 if (udev->dev.driver == NULL) {
1175 /* Non-root devices on a full/low-speed bus must wait for their
1176 * companion high-speed root hub, in case a handoff is needed.
1178 if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion)
1179 device_pm_wait_for_dev(&udev->dev,
1180 &udev->bus->hs_companion->root_hub->dev);
1182 if (udev->quirks & USB_QUIRK_RESET_RESUME)
1183 udev->reset_resume = 1;
1185 udriver = to_usb_device_driver(udev->dev.driver);
1186 status = udriver->resume(udev, msg);
1189 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1193 static int usb_suspend_interface(struct usb_device *udev,
1194 struct usb_interface *intf, pm_message_t msg)
1196 struct usb_driver *driver;
1199 if (udev->state == USB_STATE_NOTATTACHED ||
1200 intf->condition == USB_INTERFACE_UNBOUND)
1202 driver = to_usb_driver(intf->dev.driver);
1204 /* at this time we know the driver supports suspend */
1205 status = driver->suspend(intf, msg);
1206 if (status && !PMSG_IS_AUTO(msg))
1207 dev_err(&intf->dev, "suspend error %d\n", status);
1210 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1214 static int usb_resume_interface(struct usb_device *udev,
1215 struct usb_interface *intf, pm_message_t msg, int reset_resume)
1217 struct usb_driver *driver;
1220 if (udev->state == USB_STATE_NOTATTACHED)
1223 /* Don't let autoresume interfere with unbinding */
1224 if (intf->condition == USB_INTERFACE_UNBINDING)
1227 /* Can't resume it if it doesn't have a driver. */
1228 if (intf->condition == USB_INTERFACE_UNBOUND) {
1230 /* Carry out a deferred switch to altsetting 0 */
1231 if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1232 usb_set_interface(udev, intf->altsetting[0].
1233 desc.bInterfaceNumber, 0);
1234 intf->needs_altsetting0 = 0;
1239 /* Don't resume if the interface is marked for rebinding */
1240 if (intf->needs_binding)
1242 driver = to_usb_driver(intf->dev.driver);
1245 if (driver->reset_resume) {
1246 status = driver->reset_resume(intf);
1248 dev_err(&intf->dev, "%s error %d\n",
1249 "reset_resume", status);
1251 intf->needs_binding = 1;
1252 dev_dbg(&intf->dev, "no reset_resume for driver %s?\n",
1256 status = driver->resume(intf);
1258 dev_err(&intf->dev, "resume error %d\n", status);
1262 dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1264 /* Later we will unbind the driver and/or reprobe, if necessary */
1269 * usb_suspend_both - suspend a USB device and its interfaces
1270 * @udev: the usb_device to suspend
1271 * @msg: Power Management message describing this state transition
1273 * This is the central routine for suspending USB devices. It calls the
1274 * suspend methods for all the interface drivers in @udev and then calls
1275 * the suspend method for @udev itself. When the routine is called in
1276 * autosuspend, if an error occurs at any stage, all the interfaces
1277 * which were suspended are resumed so that they remain in the same
1278 * state as the device, but when called from system sleep, all error
1279 * from suspend methods of interfaces and the non-root-hub device itself
1280 * are simply ignored, so all suspended interfaces are only resumed
1281 * to the device's state when @udev is root-hub and its suspend method
1284 * Autosuspend requests originating from a child device or an interface
1285 * driver may be made without the protection of @udev's device lock, but
1286 * all other suspend calls will hold the lock. Usbcore will insure that
1287 * method calls do not arrive during bind, unbind, or reset operations.
1288 * However drivers must be prepared to handle suspend calls arriving at
1289 * unpredictable times.
1291 * This routine can run only in process context.
1293 * Return: 0 if the suspend succeeded.
1295 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1299 struct usb_interface *intf;
1301 if (udev->state == USB_STATE_NOTATTACHED ||
1302 udev->state == USB_STATE_SUSPENDED)
1305 /* Suspend all the interfaces and then udev itself */
1306 if (udev->actconfig) {
1307 n = udev->actconfig->desc.bNumInterfaces;
1308 for (i = n - 1; i >= 0; --i) {
1309 intf = udev->actconfig->interface[i];
1310 status = usb_suspend_interface(udev, intf, msg);
1312 /* Ignore errors during system sleep transitions */
1313 if (!PMSG_IS_AUTO(msg))
1320 status = usb_suspend_device(udev, msg);
1323 * Ignore errors from non-root-hub devices during
1324 * system sleep transitions. For the most part,
1325 * these devices should go to low power anyway when
1326 * the entire bus is suspended.
1328 if (udev->parent && !PMSG_IS_AUTO(msg))
1332 /* If the suspend failed, resume interfaces that did get suspended */
1334 if (udev->actconfig) {
1335 msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1337 intf = udev->actconfig->interface[i];
1338 usb_resume_interface(udev, intf, msg, 0);
1342 /* If the suspend succeeded then prevent any more URB submissions
1343 * and flush any outstanding URBs.
1346 udev->can_submit = 0;
1347 for (i = 0; i < 16; ++i) {
1348 usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1349 usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1354 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1359 * usb_resume_both - resume a USB device and its interfaces
1360 * @udev: the usb_device to resume
1361 * @msg: Power Management message describing this state transition
1363 * This is the central routine for resuming USB devices. It calls the
1364 * the resume method for @udev and then calls the resume methods for all
1365 * the interface drivers in @udev.
1367 * Autoresume requests originating from a child device or an interface
1368 * driver may be made without the protection of @udev's device lock, but
1369 * all other resume calls will hold the lock. Usbcore will insure that
1370 * method calls do not arrive during bind, unbind, or reset operations.
1371 * However drivers must be prepared to handle resume calls arriving at
1372 * unpredictable times.
1374 * This routine can run only in process context.
1376 * Return: 0 on success.
1378 static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1382 struct usb_interface *intf;
1384 if (udev->state == USB_STATE_NOTATTACHED) {
1388 udev->can_submit = 1;
1390 /* Resume the device */
1391 if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume)
1392 status = usb_resume_device(udev, msg);
1394 /* Resume the interfaces */
1395 if (status == 0 && udev->actconfig) {
1396 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1397 intf = udev->actconfig->interface[i];
1398 usb_resume_interface(udev, intf, msg,
1399 udev->reset_resume);
1402 usb_mark_last_busy(udev);
1405 dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1407 udev->reset_resume = 0;
1411 static void choose_wakeup(struct usb_device *udev, pm_message_t msg)
1415 /* Remote wakeup is needed only when we actually go to sleep.
1416 * For things like FREEZE and QUIESCE, if the device is already
1417 * autosuspended then its current wakeup setting is okay.
1419 if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
1420 if (udev->state != USB_STATE_SUSPENDED)
1421 udev->do_remote_wakeup = 0;
1425 /* Enable remote wakeup if it is allowed, even if no interface drivers
1428 w = device_may_wakeup(&udev->dev);
1430 /* If the device is autosuspended with the wrong wakeup setting,
1431 * autoresume now so the setting can be changed.
1433 if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup)
1434 pm_runtime_resume(&udev->dev);
1435 udev->do_remote_wakeup = w;
1438 /* The device lock is held by the PM core */
1439 int usb_suspend(struct device *dev, pm_message_t msg)
1441 struct usb_device *udev = to_usb_device(dev);
1443 unbind_no_pm_drivers_interfaces(udev);
1445 /* From now on we are sure all drivers support suspend/resume
1446 * but not necessarily reset_resume()
1447 * so we may still need to unbind and rebind upon resume
1449 choose_wakeup(udev, msg);
1450 return usb_suspend_both(udev, msg);
1453 /* The device lock is held by the PM core */
1454 int usb_resume_complete(struct device *dev)
1456 struct usb_device *udev = to_usb_device(dev);
1458 /* For PM complete calls, all we do is rebind interfaces
1459 * whose needs_binding flag is set
1461 if (udev->state != USB_STATE_NOTATTACHED)
1462 rebind_marked_interfaces(udev);
1466 /* The device lock is held by the PM core */
1467 int usb_resume(struct device *dev, pm_message_t msg)
1469 struct usb_device *udev = to_usb_device(dev);
1472 /* For all calls, take the device back to full power and
1473 * tell the PM core in case it was autosuspended previously.
1474 * Unbind the interfaces that will need rebinding later,
1475 * because they fail to support reset_resume.
1476 * (This can't be done in usb_resume_interface()
1477 * above because it doesn't own the right set of locks.)
1479 status = usb_resume_both(udev, msg);
1481 pm_runtime_disable(dev);
1482 pm_runtime_set_active(dev);
1483 pm_runtime_enable(dev);
1484 unbind_marked_interfaces(udev);
1487 /* Avoid PM error messages for devices disconnected while suspended
1488 * as we'll display regular disconnect messages just a bit later.
1490 if (status == -ENODEV || status == -ESHUTDOWN)
1495 #endif /* CONFIG_PM */
1497 #ifdef CONFIG_PM_RUNTIME
1500 * usb_enable_autosuspend - allow a USB device to be autosuspended
1501 * @udev: the USB device which may be autosuspended
1503 * This routine allows @udev to be autosuspended. An autosuspend won't
1504 * take place until the autosuspend_delay has elapsed and all the other
1505 * necessary conditions are satisfied.
1507 * The caller must hold @udev's device lock.
1509 void usb_enable_autosuspend(struct usb_device *udev)
1511 pm_runtime_allow(&udev->dev);
1513 EXPORT_SYMBOL_GPL(usb_enable_autosuspend);
1516 * usb_disable_autosuspend - prevent a USB device from being autosuspended
1517 * @udev: the USB device which may not be autosuspended
1519 * This routine prevents @udev from being autosuspended and wakes it up
1520 * if it is already autosuspended.
1522 * The caller must hold @udev's device lock.
1524 void usb_disable_autosuspend(struct usb_device *udev)
1526 pm_runtime_forbid(&udev->dev);
1528 EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
1531 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1532 * @udev: the usb_device to autosuspend
1534 * This routine should be called when a core subsystem is finished using
1535 * @udev and wants to allow it to autosuspend. Examples would be when
1536 * @udev's device file in usbfs is closed or after a configuration change.
1538 * @udev's usage counter is decremented; if it drops to 0 and all the
1539 * interfaces are inactive then a delayed autosuspend will be attempted.
1540 * The attempt may fail (see autosuspend_check()).
1542 * The caller must hold @udev's device lock.
1544 * This routine can run only in process context.
1546 void usb_autosuspend_device(struct usb_device *udev)
1550 usb_mark_last_busy(udev);
1551 status = pm_runtime_put_sync_autosuspend(&udev->dev);
1552 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1553 __func__, atomic_read(&udev->dev.power.usage_count),
1558 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1559 * @udev: the usb_device to autoresume
1561 * This routine should be called when a core subsystem wants to use @udev
1562 * and needs to guarantee that it is not suspended. No autosuspend will
1563 * occur until usb_autosuspend_device() is called. (Note that this will
1564 * not prevent suspend events originating in the PM core.) Examples would
1565 * be when @udev's device file in usbfs is opened or when a remote-wakeup
1566 * request is received.
1568 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1569 * However if the autoresume fails then the usage counter is re-decremented.
1571 * The caller must hold @udev's device lock.
1573 * This routine can run only in process context.
1575 * Return: 0 on success. A negative error code otherwise.
1577 int usb_autoresume_device(struct usb_device *udev)
1581 status = pm_runtime_get_sync(&udev->dev);
1583 pm_runtime_put_sync(&udev->dev);
1584 dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1585 __func__, atomic_read(&udev->dev.power.usage_count),
1593 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1594 * @intf: the usb_interface whose counter should be decremented
1596 * This routine should be called by an interface driver when it is
1597 * finished using @intf and wants to allow it to autosuspend. A typical
1598 * example would be a character-device driver when its device file is
1601 * The routine decrements @intf's usage counter. When the counter reaches
1602 * 0, a delayed autosuspend request for @intf's device is attempted. The
1603 * attempt may fail (see autosuspend_check()).
1605 * This routine can run only in process context.
1607 void usb_autopm_put_interface(struct usb_interface *intf)
1609 struct usb_device *udev = interface_to_usbdev(intf);
1612 usb_mark_last_busy(udev);
1613 atomic_dec(&intf->pm_usage_cnt);
1614 status = pm_runtime_put_sync(&intf->dev);
1615 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1616 __func__, atomic_read(&intf->dev.power.usage_count),
1619 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1622 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1623 * @intf: the usb_interface whose counter should be decremented
1625 * This routine does much the same thing as usb_autopm_put_interface():
1626 * It decrements @intf's usage counter and schedules a delayed
1627 * autosuspend request if the counter is <= 0. The difference is that it
1628 * does not perform any synchronization; callers should hold a private
1629 * lock and handle all synchronization issues themselves.
1631 * Typically a driver would call this routine during an URB's completion
1632 * handler, if no more URBs were pending.
1634 * This routine can run in atomic context.
1636 void usb_autopm_put_interface_async(struct usb_interface *intf)
1638 struct usb_device *udev = interface_to_usbdev(intf);
1641 usb_mark_last_busy(udev);
1642 atomic_dec(&intf->pm_usage_cnt);
1643 status = pm_runtime_put(&intf->dev);
1644 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1645 __func__, atomic_read(&intf->dev.power.usage_count),
1648 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1651 * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
1652 * @intf: the usb_interface whose counter should be decremented
1654 * This routine decrements @intf's usage counter but does not carry out an
1657 * This routine can run in atomic context.
1659 void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
1661 struct usb_device *udev = interface_to_usbdev(intf);
1663 usb_mark_last_busy(udev);
1664 atomic_dec(&intf->pm_usage_cnt);
1665 pm_runtime_put_noidle(&intf->dev);
1667 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
1670 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1671 * @intf: the usb_interface whose counter should be incremented
1673 * This routine should be called by an interface driver when it wants to
1674 * use @intf and needs to guarantee that it is not suspended. In addition,
1675 * the routine prevents @intf from being autosuspended subsequently. (Note
1676 * that this will not prevent suspend events originating in the PM core.)
1677 * This prevention will persist until usb_autopm_put_interface() is called
1678 * or @intf is unbound. A typical example would be a character-device
1679 * driver when its device file is opened.
1681 * @intf's usage counter is incremented to prevent subsequent autosuspends.
1682 * However if the autoresume fails then the counter is re-decremented.
1684 * This routine can run only in process context.
1686 * Return: 0 on success.
1688 int usb_autopm_get_interface(struct usb_interface *intf)
1692 status = pm_runtime_get_sync(&intf->dev);
1694 pm_runtime_put_sync(&intf->dev);
1696 atomic_inc(&intf->pm_usage_cnt);
1697 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1698 __func__, atomic_read(&intf->dev.power.usage_count),
1704 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1707 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1708 * @intf: the usb_interface whose counter should be incremented
1710 * This routine does much the same thing as
1711 * usb_autopm_get_interface(): It increments @intf's usage counter and
1712 * queues an autoresume request if the device is suspended. The
1713 * differences are that it does not perform any synchronization (callers
1714 * should hold a private lock and handle all synchronization issues
1715 * themselves), and it does not autoresume the device directly (it only
1716 * queues a request). After a successful call, the device may not yet be
1719 * This routine can run in atomic context.
1721 * Return: 0 on success. A negative error code otherwise.
1723 int usb_autopm_get_interface_async(struct usb_interface *intf)
1727 status = pm_runtime_get(&intf->dev);
1728 if (status < 0 && status != -EINPROGRESS)
1729 pm_runtime_put_noidle(&intf->dev);
1731 atomic_inc(&intf->pm_usage_cnt);
1732 dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1733 __func__, atomic_read(&intf->dev.power.usage_count),
1735 if (status > 0 || status == -EINPROGRESS)
1739 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1742 * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
1743 * @intf: the usb_interface whose counter should be incremented
1745 * This routine increments @intf's usage counter but does not carry out an
1748 * This routine can run in atomic context.
1750 void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
1752 struct usb_device *udev = interface_to_usbdev(intf);
1754 usb_mark_last_busy(udev);
1755 atomic_inc(&intf->pm_usage_cnt);
1756 pm_runtime_get_noresume(&intf->dev);
1758 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
1760 /* Internal routine to check whether we may autosuspend a device. */
1761 static int autosuspend_check(struct usb_device *udev)
1764 struct usb_interface *intf;
1766 /* Fail if autosuspend is disabled, or any interfaces are in use, or
1767 * any interface drivers require remote wakeup but it isn't available.
1770 if (udev->actconfig) {
1771 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1772 intf = udev->actconfig->interface[i];
1774 /* We don't need to check interfaces that are
1775 * disabled for runtime PM. Either they are unbound
1776 * or else their drivers don't support autosuspend
1777 * and so they are permanently active.
1779 if (intf->dev.power.disable_depth)
1781 if (atomic_read(&intf->dev.power.usage_count) > 0)
1783 w |= intf->needs_remote_wakeup;
1785 /* Don't allow autosuspend if the device will need
1786 * a reset-resume and any of its interface drivers
1787 * doesn't include support or needs remote wakeup.
1789 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1790 struct usb_driver *driver;
1792 driver = to_usb_driver(intf->dev.driver);
1793 if (!driver->reset_resume ||
1794 intf->needs_remote_wakeup)
1799 if (w && !device_can_wakeup(&udev->dev)) {
1800 dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
1803 udev->do_remote_wakeup = w;
1807 int usb_runtime_suspend(struct device *dev)
1809 struct usb_device *udev = to_usb_device(dev);
1812 /* A USB device can be suspended if it passes the various autosuspend
1813 * checks. Runtime suspend for a USB device means suspending all the
1814 * interfaces and then the device itself.
1816 if (autosuspend_check(udev) != 0)
1819 status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1821 /* Allow a retry if autosuspend failed temporarily */
1822 if (status == -EAGAIN || status == -EBUSY)
1823 usb_mark_last_busy(udev);
1825 /* The PM core reacts badly unless the return code is 0,
1826 * -EAGAIN, or -EBUSY, so always return -EBUSY on an error.
1833 int usb_runtime_resume(struct device *dev)
1835 struct usb_device *udev = to_usb_device(dev);
1838 /* Runtime resume for a USB device means resuming both the device
1839 * and all its interfaces.
1841 status = usb_resume_both(udev, PMSG_AUTO_RESUME);
1845 int usb_runtime_idle(struct device *dev)
1847 struct usb_device *udev = to_usb_device(dev);
1849 /* An idle USB device can be suspended if it passes the various
1850 * autosuspend checks.
1852 if (autosuspend_check(udev) == 0)
1853 pm_runtime_autosuspend(dev);
1854 /* Tell the core not to suspend it, though. */
1858 int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
1860 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1863 if (enable && !udev->usb2_hw_lpm_allowed)
1866 if (hcd->driver->set_usb2_hw_lpm) {
1867 ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable);
1869 udev->usb2_hw_lpm_enabled = enable;
1875 #endif /* CONFIG_PM_RUNTIME */
1877 struct bus_type usb_bus_type = {
1879 .match = usb_device_match,
1880 .uevent = usb_uevent,