2 * drivers/usb/driver.c - most of the driver model stuff for usb
4 * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
6 * based on drivers/usb/usb.c which had the following copyrights:
7 * (C) Copyright Linus Torvalds 1999
8 * (C) Copyright Johannes Erdfelt 1999-2001
9 * (C) Copyright Andreas Gal 1999
10 * (C) Copyright Gregory P. Smith 1999
11 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
12 * (C) Copyright Randy Dunlap 2000
13 * (C) Copyright David Brownell 2000-2004
14 * (C) Copyright Yggdrasil Computing, Inc. 2000
15 * (usb_device_id matching changes by Adam J. Richter)
16 * (C) Copyright Greg Kroah-Hartman 2002-2003
18 * NOTE! This is not actually a driver at all, rather this is
19 * just a collection of helper routines that implement the
20 * matching, probing, releasing, suspending and resuming for
25 #include <linux/device.h>
26 #include <linux/usb.h>
27 #include <linux/usb/quirks.h>
28 #include <linux/workqueue.h>
36 * Adds a new dynamic USBdevice ID to this driver,
37 * and cause the driver to probe for all devices again.
39 ssize_t
usb_store_new_id(struct usb_dynids
*dynids
,
40 struct device_driver
*driver
,
41 const char *buf
, size_t count
)
43 struct usb_dynid
*dynid
;
49 fields
= sscanf(buf
, "%x %x", &idVendor
, &idProduct
);
53 dynid
= kzalloc(sizeof(*dynid
), GFP_KERNEL
);
57 INIT_LIST_HEAD(&dynid
->node
);
58 dynid
->id
.idVendor
= idVendor
;
59 dynid
->id
.idProduct
= idProduct
;
60 dynid
->id
.match_flags
= USB_DEVICE_ID_MATCH_DEVICE
;
62 spin_lock(&dynids
->lock
);
63 list_add_tail(&dynid
->node
, &dynids
->list
);
64 spin_unlock(&dynids
->lock
);
66 if (get_driver(driver
)) {
67 retval
= driver_attach(driver
);
75 EXPORT_SYMBOL_GPL(usb_store_new_id
);
77 static ssize_t
store_new_id(struct device_driver
*driver
,
78 const char *buf
, size_t count
)
80 struct usb_driver
*usb_drv
= to_usb_driver(driver
);
82 return usb_store_new_id(&usb_drv
->dynids
, driver
, buf
, count
);
84 static DRIVER_ATTR(new_id
, S_IWUSR
, NULL
, store_new_id
);
86 static int usb_create_newid_file(struct usb_driver
*usb_drv
)
90 if (usb_drv
->no_dynamic_id
)
93 if (usb_drv
->probe
!= NULL
)
94 error
= driver_create_file(&usb_drv
->drvwrap
.driver
,
100 static void usb_remove_newid_file(struct usb_driver
*usb_drv
)
102 if (usb_drv
->no_dynamic_id
)
105 if (usb_drv
->probe
!= NULL
)
106 driver_remove_file(&usb_drv
->drvwrap
.driver
,
107 &driver_attr_new_id
);
110 static void usb_free_dynids(struct usb_driver
*usb_drv
)
112 struct usb_dynid
*dynid
, *n
;
114 spin_lock(&usb_drv
->dynids
.lock
);
115 list_for_each_entry_safe(dynid
, n
, &usb_drv
->dynids
.list
, node
) {
116 list_del(&dynid
->node
);
119 spin_unlock(&usb_drv
->dynids
.lock
);
122 static inline int usb_create_newid_file(struct usb_driver
*usb_drv
)
127 static void usb_remove_newid_file(struct usb_driver
*usb_drv
)
131 static inline void usb_free_dynids(struct usb_driver
*usb_drv
)
136 static const struct usb_device_id
*usb_match_dynamic_id(struct usb_interface
*intf
,
137 struct usb_driver
*drv
)
139 struct usb_dynid
*dynid
;
141 spin_lock(&drv
->dynids
.lock
);
142 list_for_each_entry(dynid
, &drv
->dynids
.list
, node
) {
143 if (usb_match_one_id(intf
, &dynid
->id
)) {
144 spin_unlock(&drv
->dynids
.lock
);
148 spin_unlock(&drv
->dynids
.lock
);
153 /* called from driver core with dev locked */
154 static int usb_probe_device(struct device
*dev
)
156 struct usb_device_driver
*udriver
= to_usb_device_driver(dev
->driver
);
157 struct usb_device
*udev
;
160 dev_dbg(dev
, "%s\n", __func__
);
162 if (!is_usb_device(dev
)) /* Sanity check */
165 udev
= to_usb_device(dev
);
167 /* TODO: Add real matching code */
169 /* The device should always appear to be in use
170 * unless the driver suports autosuspend.
172 udev
->pm_usage_cnt
= !(udriver
->supports_autosuspend
);
174 error
= udriver
->probe(udev
);
178 /* called from driver core with dev locked */
179 static int usb_unbind_device(struct device
*dev
)
181 struct usb_device_driver
*udriver
= to_usb_device_driver(dev
->driver
);
183 udriver
->disconnect(to_usb_device(dev
));
188 /* called from driver core with dev locked */
189 static int usb_probe_interface(struct device
*dev
)
191 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
192 struct usb_interface
*intf
;
193 struct usb_device
*udev
;
194 const struct usb_device_id
*id
;
197 dev_dbg(dev
, "%s\n", __func__
);
199 if (is_usb_device(dev
)) /* Sanity check */
202 intf
= to_usb_interface(dev
);
203 udev
= interface_to_usbdev(intf
);
204 intf
->needs_binding
= 0;
206 if (udev
->authorized
== 0) {
207 dev_err(&intf
->dev
, "Device is not authorized for usage\n");
211 id
= usb_match_id(intf
, driver
->id_table
);
213 id
= usb_match_dynamic_id(intf
, driver
);
215 dev_dbg(dev
, "%s - got id\n", __func__
);
217 error
= usb_autoresume_device(udev
);
221 /* Interface "power state" doesn't correspond to any hardware
222 * state whatsoever. We use it to record when it's bound to
223 * a driver that may start I/0: it's not frozen/quiesced.
226 intf
->condition
= USB_INTERFACE_BINDING
;
228 /* The interface should always appear to be in use
229 * unless the driver suports autosuspend.
231 intf
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
233 error
= driver
->probe(intf
, id
);
236 intf
->needs_remote_wakeup
= 0;
237 intf
->condition
= USB_INTERFACE_UNBOUND
;
239 intf
->condition
= USB_INTERFACE_BOUND
;
241 usb_autosuspend_device(udev
);
247 /* called from driver core with dev locked */
248 static int usb_unbind_interface(struct device
*dev
)
250 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
251 struct usb_interface
*intf
= to_usb_interface(dev
);
252 struct usb_device
*udev
;
255 intf
->condition
= USB_INTERFACE_UNBINDING
;
257 /* Autoresume for set_interface call below */
258 udev
= interface_to_usbdev(intf
);
259 error
= usb_autoresume_device(udev
);
261 /* Terminate all URBs for this interface unless the driver
262 * supports "soft" unbinding.
264 if (!driver
->soft_unbind
)
265 usb_disable_interface(udev
, intf
);
267 driver
->disconnect(intf
);
269 /* reset other interface state */
270 usb_set_interface(udev
, intf
->altsetting
[0].desc
.bInterfaceNumber
, 0);
271 usb_set_intfdata(intf
, NULL
);
273 intf
->condition
= USB_INTERFACE_UNBOUND
;
275 intf
->needs_remote_wakeup
= 0;
278 usb_autosuspend_device(udev
);
284 * usb_driver_claim_interface - bind a driver to an interface
285 * @driver: the driver to be bound
286 * @iface: the interface to which it will be bound; must be in the
287 * usb device's active configuration
288 * @priv: driver data associated with that interface
290 * This is used by usb device drivers that need to claim more than one
291 * interface on a device when probing (audio and acm are current examples).
292 * No device driver should directly modify internal usb_interface or
293 * usb_device structure members.
295 * Few drivers should need to use this routine, since the most natural
296 * way to bind to an interface is to return the private data from
297 * the driver's probe() method.
299 * Callers must own the device lock, so driver probe() entries don't need
300 * extra locking, but other call contexts may need to explicitly claim that
303 int usb_driver_claim_interface(struct usb_driver
*driver
,
304 struct usb_interface
*iface
, void *priv
)
306 struct device
*dev
= &iface
->dev
;
307 struct usb_device
*udev
= interface_to_usbdev(iface
);
313 dev
->driver
= &driver
->drvwrap
.driver
;
314 usb_set_intfdata(iface
, priv
);
315 iface
->needs_binding
= 0;
318 iface
->condition
= USB_INTERFACE_BOUND
;
320 iface
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
323 /* if interface was already added, bind now; else let
324 * the future device_add() bind it, bypassing probe()
326 if (device_is_registered(dev
))
327 retval
= device_bind_driver(dev
);
331 EXPORT_SYMBOL_GPL(usb_driver_claim_interface
);
334 * usb_driver_release_interface - unbind a driver from an interface
335 * @driver: the driver to be unbound
336 * @iface: the interface from which it will be unbound
338 * This can be used by drivers to release an interface without waiting
339 * for their disconnect() methods to be called. In typical cases this
340 * also causes the driver disconnect() method to be called.
342 * This call is synchronous, and may not be used in an interrupt context.
343 * Callers must own the device lock, so driver disconnect() entries don't
344 * need extra locking, but other call contexts may need to explicitly claim
347 void usb_driver_release_interface(struct usb_driver
*driver
,
348 struct usb_interface
*iface
)
350 struct device
*dev
= &iface
->dev
;
351 struct usb_device
*udev
= interface_to_usbdev(iface
);
353 /* this should never happen, don't release something that's not ours */
354 if (!dev
->driver
|| dev
->driver
!= &driver
->drvwrap
.driver
)
357 /* don't release from within disconnect() */
358 if (iface
->condition
!= USB_INTERFACE_BOUND
)
361 /* don't release if the interface hasn't been added yet */
362 if (device_is_registered(dev
)) {
363 iface
->condition
= USB_INTERFACE_UNBINDING
;
364 device_release_driver(dev
);
368 usb_set_intfdata(iface
, NULL
);
371 iface
->condition
= USB_INTERFACE_UNBOUND
;
372 mark_quiesced(iface
);
373 iface
->needs_remote_wakeup
= 0;
376 EXPORT_SYMBOL_GPL(usb_driver_release_interface
);
378 /* returns 0 if no match, 1 if match */
379 int usb_match_device(struct usb_device
*dev
, const struct usb_device_id
*id
)
381 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
382 id
->idVendor
!= le16_to_cpu(dev
->descriptor
.idVendor
))
385 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_PRODUCT
) &&
386 id
->idProduct
!= le16_to_cpu(dev
->descriptor
.idProduct
))
389 /* No need to test id->bcdDevice_lo != 0, since 0 is never
390 greater than any unsigned number. */
391 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_LO
) &&
392 (id
->bcdDevice_lo
> le16_to_cpu(dev
->descriptor
.bcdDevice
)))
395 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_HI
) &&
396 (id
->bcdDevice_hi
< le16_to_cpu(dev
->descriptor
.bcdDevice
)))
399 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_CLASS
) &&
400 (id
->bDeviceClass
!= dev
->descriptor
.bDeviceClass
))
403 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_SUBCLASS
) &&
404 (id
->bDeviceSubClass
!= dev
->descriptor
.bDeviceSubClass
))
407 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_PROTOCOL
) &&
408 (id
->bDeviceProtocol
!= dev
->descriptor
.bDeviceProtocol
))
414 /* returns 0 if no match, 1 if match */
415 int usb_match_one_id(struct usb_interface
*interface
,
416 const struct usb_device_id
*id
)
418 struct usb_host_interface
*intf
;
419 struct usb_device
*dev
;
421 /* proc_connectinfo in devio.c may call us with id == NULL. */
425 intf
= interface
->cur_altsetting
;
426 dev
= interface_to_usbdev(interface
);
428 if (!usb_match_device(dev
, id
))
431 /* The interface class, subclass, and protocol should never be
432 * checked for a match if the device class is Vendor Specific,
433 * unless the match record specifies the Vendor ID. */
434 if (dev
->descriptor
.bDeviceClass
== USB_CLASS_VENDOR_SPEC
&&
435 !(id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
436 (id
->match_flags
& (USB_DEVICE_ID_MATCH_INT_CLASS
|
437 USB_DEVICE_ID_MATCH_INT_SUBCLASS
|
438 USB_DEVICE_ID_MATCH_INT_PROTOCOL
)))
441 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_CLASS
) &&
442 (id
->bInterfaceClass
!= intf
->desc
.bInterfaceClass
))
445 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_SUBCLASS
) &&
446 (id
->bInterfaceSubClass
!= intf
->desc
.bInterfaceSubClass
))
449 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_PROTOCOL
) &&
450 (id
->bInterfaceProtocol
!= intf
->desc
.bInterfaceProtocol
))
455 EXPORT_SYMBOL_GPL(usb_match_one_id
);
458 * usb_match_id - find first usb_device_id matching device or interface
459 * @interface: the interface of interest
460 * @id: array of usb_device_id structures, terminated by zero entry
462 * usb_match_id searches an array of usb_device_id's and returns
463 * the first one matching the device or interface, or null.
464 * This is used when binding (or rebinding) a driver to an interface.
465 * Most USB device drivers will use this indirectly, through the usb core,
466 * but some layered driver frameworks use it directly.
467 * These device tables are exported with MODULE_DEVICE_TABLE, through
468 * modutils, to support the driver loading functionality of USB hotplugging.
472 * The "match_flags" element in a usb_device_id controls which
473 * members are used. If the corresponding bit is set, the
474 * value in the device_id must match its corresponding member
475 * in the device or interface descriptor, or else the device_id
478 * "driver_info" is normally used only by device drivers,
479 * but you can create a wildcard "matches anything" usb_device_id
480 * as a driver's "modules.usbmap" entry if you provide an id with
481 * only a nonzero "driver_info" field. If you do this, the USB device
482 * driver's probe() routine should use additional intelligence to
483 * decide whether to bind to the specified interface.
485 * What Makes Good usb_device_id Tables:
487 * The match algorithm is very simple, so that intelligence in
488 * driver selection must come from smart driver id records.
489 * Unless you have good reasons to use another selection policy,
490 * provide match elements only in related groups, and order match
491 * specifiers from specific to general. Use the macros provided
492 * for that purpose if you can.
494 * The most specific match specifiers use device descriptor
495 * data. These are commonly used with product-specific matches;
496 * the USB_DEVICE macro lets you provide vendor and product IDs,
497 * and you can also match against ranges of product revisions.
498 * These are widely used for devices with application or vendor
499 * specific bDeviceClass values.
501 * Matches based on device class/subclass/protocol specifications
502 * are slightly more general; use the USB_DEVICE_INFO macro, or
503 * its siblings. These are used with single-function devices
504 * where bDeviceClass doesn't specify that each interface has
507 * Matches based on interface class/subclass/protocol are the
508 * most general; they let drivers bind to any interface on a
509 * multiple-function device. Use the USB_INTERFACE_INFO
510 * macro, or its siblings, to match class-per-interface style
511 * devices (as recorded in bInterfaceClass).
513 * Note that an entry created by USB_INTERFACE_INFO won't match
514 * any interface if the device class is set to Vendor-Specific.
515 * This is deliberate; according to the USB spec the meanings of
516 * the interface class/subclass/protocol for these devices are also
517 * vendor-specific, and hence matching against a standard product
518 * class wouldn't work anyway. If you really want to use an
519 * interface-based match for such a device, create a match record
520 * that also specifies the vendor ID. (Unforunately there isn't a
521 * standard macro for creating records like this.)
523 * Within those groups, remember that not all combinations are
524 * meaningful. For example, don't give a product version range
525 * without vendor and product IDs; or specify a protocol without
526 * its associated class and subclass.
528 const struct usb_device_id
*usb_match_id(struct usb_interface
*interface
,
529 const struct usb_device_id
*id
)
531 /* proc_connectinfo in devio.c may call us with id == NULL. */
535 /* It is important to check that id->driver_info is nonzero,
536 since an entry that is all zeroes except for a nonzero
537 id->driver_info is the way to create an entry that
538 indicates that the driver want to examine every
539 device and interface. */
540 for (; id
->idVendor
|| id
->idProduct
|| id
->bDeviceClass
||
541 id
->bInterfaceClass
|| id
->driver_info
; id
++) {
542 if (usb_match_one_id(interface
, id
))
548 EXPORT_SYMBOL_GPL(usb_match_id
);
550 static int usb_device_match(struct device
*dev
, struct device_driver
*drv
)
552 /* devices and interfaces are handled separately */
553 if (is_usb_device(dev
)) {
555 /* interface drivers never match devices */
556 if (!is_usb_device_driver(drv
))
559 /* TODO: Add real matching code */
563 struct usb_interface
*intf
;
564 struct usb_driver
*usb_drv
;
565 const struct usb_device_id
*id
;
567 /* device drivers never match interfaces */
568 if (is_usb_device_driver(drv
))
571 intf
= to_usb_interface(dev
);
572 usb_drv
= to_usb_driver(drv
);
574 id
= usb_match_id(intf
, usb_drv
->id_table
);
578 id
= usb_match_dynamic_id(intf
, usb_drv
);
586 #ifdef CONFIG_HOTPLUG
587 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
589 struct usb_device
*usb_dev
;
591 /* driver is often null here; dev_dbg() would oops */
592 pr_debug("usb %s: uevent\n", dev_name(dev
));
594 if (is_usb_device(dev
))
595 usb_dev
= to_usb_device(dev
);
597 struct usb_interface
*intf
= to_usb_interface(dev
);
598 usb_dev
= interface_to_usbdev(intf
);
601 if (usb_dev
->devnum
< 0) {
602 pr_debug("usb %s: already deleted?\n", dev_name(dev
));
606 pr_debug("usb %s: bus removed?\n", dev_name(dev
));
610 #ifdef CONFIG_USB_DEVICEFS
611 /* If this is available, userspace programs can directly read
612 * all the device descriptors we don't tell them about. Or
613 * act as usermode drivers.
615 if (add_uevent_var(env
, "DEVICE=/proc/bus/usb/%03d/%03d",
616 usb_dev
->bus
->busnum
, usb_dev
->devnum
))
620 /* per-device configurations are common */
621 if (add_uevent_var(env
, "PRODUCT=%x/%x/%x",
622 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
623 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
624 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
)))
627 /* class-based driver binding models */
628 if (add_uevent_var(env
, "TYPE=%d/%d/%d",
629 usb_dev
->descriptor
.bDeviceClass
,
630 usb_dev
->descriptor
.bDeviceSubClass
,
631 usb_dev
->descriptor
.bDeviceProtocol
))
639 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
643 #endif /* CONFIG_HOTPLUG */
646 * usb_register_device_driver - register a USB device (not interface) driver
647 * @new_udriver: USB operations for the device driver
648 * @owner: module owner of this driver.
650 * Registers a USB device driver with the USB core. The list of
651 * unattached devices will be rescanned whenever a new driver is
652 * added, allowing the new driver to attach to any recognized devices.
653 * Returns a negative error code on failure and 0 on success.
655 int usb_register_device_driver(struct usb_device_driver
*new_udriver
,
656 struct module
*owner
)
663 new_udriver
->drvwrap
.for_devices
= 1;
664 new_udriver
->drvwrap
.driver
.name
= (char *) new_udriver
->name
;
665 new_udriver
->drvwrap
.driver
.bus
= &usb_bus_type
;
666 new_udriver
->drvwrap
.driver
.probe
= usb_probe_device
;
667 new_udriver
->drvwrap
.driver
.remove
= usb_unbind_device
;
668 new_udriver
->drvwrap
.driver
.owner
= owner
;
670 retval
= driver_register(&new_udriver
->drvwrap
.driver
);
673 pr_info("%s: registered new device driver %s\n",
674 usbcore_name
, new_udriver
->name
);
675 usbfs_update_special();
677 printk(KERN_ERR
"%s: error %d registering device "
679 usbcore_name
, retval
, new_udriver
->name
);
684 EXPORT_SYMBOL_GPL(usb_register_device_driver
);
687 * usb_deregister_device_driver - unregister a USB device (not interface) driver
688 * @udriver: USB operations of the device driver to unregister
689 * Context: must be able to sleep
691 * Unlinks the specified driver from the internal USB driver list.
693 void usb_deregister_device_driver(struct usb_device_driver
*udriver
)
695 pr_info("%s: deregistering device driver %s\n",
696 usbcore_name
, udriver
->name
);
698 driver_unregister(&udriver
->drvwrap
.driver
);
699 usbfs_update_special();
701 EXPORT_SYMBOL_GPL(usb_deregister_device_driver
);
704 * usb_register_driver - register a USB interface driver
705 * @new_driver: USB operations for the interface driver
706 * @owner: module owner of this driver.
707 * @mod_name: module name string
709 * Registers a USB interface driver with the USB core. The list of
710 * unattached interfaces will be rescanned whenever a new driver is
711 * added, allowing the new driver to attach to any recognized interfaces.
712 * Returns a negative error code on failure and 0 on success.
714 * NOTE: if you want your driver to use the USB major number, you must call
715 * usb_register_dev() to enable that functionality. This function no longer
716 * takes care of that.
718 int usb_register_driver(struct usb_driver
*new_driver
, struct module
*owner
,
719 const char *mod_name
)
726 new_driver
->drvwrap
.for_devices
= 0;
727 new_driver
->drvwrap
.driver
.name
= (char *) new_driver
->name
;
728 new_driver
->drvwrap
.driver
.bus
= &usb_bus_type
;
729 new_driver
->drvwrap
.driver
.probe
= usb_probe_interface
;
730 new_driver
->drvwrap
.driver
.remove
= usb_unbind_interface
;
731 new_driver
->drvwrap
.driver
.owner
= owner
;
732 new_driver
->drvwrap
.driver
.mod_name
= mod_name
;
733 spin_lock_init(&new_driver
->dynids
.lock
);
734 INIT_LIST_HEAD(&new_driver
->dynids
.list
);
736 retval
= driver_register(&new_driver
->drvwrap
.driver
);
739 pr_info("%s: registered new interface driver %s\n",
740 usbcore_name
, new_driver
->name
);
741 usbfs_update_special();
742 usb_create_newid_file(new_driver
);
744 printk(KERN_ERR
"%s: error %d registering interface "
746 usbcore_name
, retval
, new_driver
->name
);
751 EXPORT_SYMBOL_GPL(usb_register_driver
);
754 * usb_deregister - unregister a USB interface driver
755 * @driver: USB operations of the interface driver to unregister
756 * Context: must be able to sleep
758 * Unlinks the specified driver from the internal USB driver list.
760 * NOTE: If you called usb_register_dev(), you still need to call
761 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
762 * this * call will no longer do it for you.
764 void usb_deregister(struct usb_driver
*driver
)
766 pr_info("%s: deregistering interface driver %s\n",
767 usbcore_name
, driver
->name
);
769 usb_remove_newid_file(driver
);
770 usb_free_dynids(driver
);
771 driver_unregister(&driver
->drvwrap
.driver
);
773 usbfs_update_special();
775 EXPORT_SYMBOL_GPL(usb_deregister
);
778 /* Forced unbinding of a USB interface driver, either because
779 * it doesn't support pre_reset/post_reset/reset_resume or
780 * because it doesn't support suspend/resume.
782 * The caller must hold @intf's device's lock, but not its pm_mutex
783 * and not @intf->dev.sem.
785 void usb_forced_unbind_intf(struct usb_interface
*intf
)
787 struct usb_driver
*driver
= to_usb_driver(intf
->dev
.driver
);
789 dev_dbg(&intf
->dev
, "forced unbind\n");
790 usb_driver_release_interface(driver
, intf
);
792 /* Mark the interface for later rebinding */
793 intf
->needs_binding
= 1;
796 /* Delayed forced unbinding of a USB interface driver and scan
799 * The caller must hold @intf's device's lock, but not its pm_mutex
800 * and not @intf->dev.sem.
802 * FIXME: The caller must block system sleep transitions.
804 void usb_rebind_intf(struct usb_interface
*intf
)
808 /* Delayed unbind of an existing driver */
809 if (intf
->dev
.driver
) {
810 struct usb_driver
*driver
=
811 to_usb_driver(intf
->dev
.driver
);
813 dev_dbg(&intf
->dev
, "forced unbind\n");
814 usb_driver_release_interface(driver
, intf
);
817 /* Try to rebind the interface */
818 intf
->needs_binding
= 0;
819 rc
= device_attach(&intf
->dev
);
821 dev_warn(&intf
->dev
, "rebind failed: %d\n", rc
);
827 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
828 * or rebind interfaces that have been unbound, according to @action.
830 * The caller must hold @udev's device lock.
831 * FIXME: For rebinds, the caller must block system sleep transitions.
833 static void do_unbind_rebind(struct usb_device
*udev
, int action
)
835 struct usb_host_config
*config
;
837 struct usb_interface
*intf
;
838 struct usb_driver
*drv
;
840 config
= udev
->actconfig
;
842 for (i
= 0; i
< config
->desc
.bNumInterfaces
; ++i
) {
843 intf
= config
->interface
[i
];
846 if (intf
->dev
.driver
) {
847 drv
= to_usb_driver(intf
->dev
.driver
);
848 if (!drv
->suspend
|| !drv
->resume
)
849 usb_forced_unbind_intf(intf
);
853 if (intf
->needs_binding
) {
855 /* FIXME: The next line is needed because we are going to probe
856 * the interface, but as far as the PM core is concerned the
857 * interface is still suspended. The problem wouldn't exist
858 * if we could rebind the interface during the interface's own
859 * resume() call, but at the time the usb_device isn't locked!
861 * The real solution will be to carry this out during the device's
862 * complete() callback. Until that is implemented, we have to
865 // intf->dev.power.sleeping = 0;
867 usb_rebind_intf(intf
);
877 /* Caller has locked udev's pm_mutex */
878 static int usb_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
880 struct usb_device_driver
*udriver
;
883 if (udev
->state
== USB_STATE_NOTATTACHED
||
884 udev
->state
== USB_STATE_SUSPENDED
)
887 /* For devices that don't have a driver, we do a generic suspend. */
888 if (udev
->dev
.driver
)
889 udriver
= to_usb_device_driver(udev
->dev
.driver
);
891 udev
->do_remote_wakeup
= 0;
892 udriver
= &usb_generic_driver
;
894 status
= udriver
->suspend(udev
, msg
);
897 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
901 /* Caller has locked udev's pm_mutex */
902 static int usb_resume_device(struct usb_device
*udev
)
904 struct usb_device_driver
*udriver
;
907 if (udev
->state
== USB_STATE_NOTATTACHED
)
910 /* Can't resume it if it doesn't have a driver. */
911 if (udev
->dev
.driver
== NULL
) {
916 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
)
917 udev
->reset_resume
= 1;
919 udriver
= to_usb_device_driver(udev
->dev
.driver
);
920 status
= udriver
->resume(udev
);
923 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
925 udev
->autoresume_disabled
= 0;
929 /* Caller has locked intf's usb_device's pm mutex */
930 static int usb_suspend_interface(struct usb_interface
*intf
, pm_message_t msg
)
932 struct usb_driver
*driver
;
935 /* with no hardware, USB interfaces only use FREEZE and ON states */
936 if (interface_to_usbdev(intf
)->state
== USB_STATE_NOTATTACHED
||
940 if (intf
->condition
== USB_INTERFACE_UNBOUND
) /* This can't happen */
942 driver
= to_usb_driver(intf
->dev
.driver
);
944 if (driver
->suspend
) {
945 status
= driver
->suspend(intf
, msg
);
948 else if (!interface_to_usbdev(intf
)->auto_pm
)
949 dev_err(&intf
->dev
, "%s error %d\n",
952 /* Later we will unbind the driver and reprobe */
953 intf
->needs_binding
= 1;
954 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
955 "suspend", driver
->name
);
960 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
964 /* Caller has locked intf's usb_device's pm_mutex */
965 static int usb_resume_interface(struct usb_interface
*intf
, int reset_resume
)
967 struct usb_driver
*driver
;
970 if (interface_to_usbdev(intf
)->state
== USB_STATE_NOTATTACHED
||
974 /* Don't let autoresume interfere with unbinding */
975 if (intf
->condition
== USB_INTERFACE_UNBINDING
)
978 /* Can't resume it if it doesn't have a driver. */
979 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
982 /* Don't resume if the interface is marked for rebinding */
983 if (intf
->needs_binding
)
985 driver
= to_usb_driver(intf
->dev
.driver
);
988 if (driver
->reset_resume
) {
989 status
= driver
->reset_resume(intf
);
991 dev_err(&intf
->dev
, "%s error %d\n",
992 "reset_resume", status
);
994 intf
->needs_binding
= 1;
995 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
996 "reset_resume", driver
->name
);
999 if (driver
->resume
) {
1000 status
= driver
->resume(intf
);
1002 dev_err(&intf
->dev
, "%s error %d\n",
1005 intf
->needs_binding
= 1;
1006 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1007 "resume", driver
->name
);
1012 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
1013 if (status
== 0 && intf
->condition
== USB_INTERFACE_BOUND
)
1016 /* Later we will unbind the driver and/or reprobe, if necessary */
1020 #ifdef CONFIG_USB_SUSPEND
1022 /* Internal routine to check whether we may autosuspend a device. */
1023 static int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1026 struct usb_interface
*intf
;
1027 unsigned long suspend_time
, j
;
1029 /* For autosuspend, fail fast if anything is in use or autosuspend
1030 * is disabled. Also fail if any interfaces require remote wakeup
1031 * but it isn't available.
1033 if (udev
->pm_usage_cnt
> 0)
1035 if (udev
->autosuspend_delay
< 0 || udev
->autosuspend_disabled
)
1038 suspend_time
= udev
->last_busy
+ udev
->autosuspend_delay
;
1039 if (udev
->actconfig
) {
1040 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1041 intf
= udev
->actconfig
->interface
[i
];
1042 if (!is_active(intf
))
1044 if (intf
->pm_usage_cnt
> 0)
1046 if (intf
->needs_remote_wakeup
&&
1047 !udev
->do_remote_wakeup
) {
1048 dev_dbg(&udev
->dev
, "remote wakeup needed "
1049 "for autosuspend\n");
1053 /* Don't allow autosuspend if the device will need
1054 * a reset-resume and any of its interface drivers
1055 * doesn't include support.
1057 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
) {
1058 struct usb_driver
*driver
;
1060 driver
= to_usb_driver(intf
->dev
.driver
);
1061 if (!driver
->reset_resume
)
1067 /* If everything is okay but the device hasn't been idle for long
1068 * enough, queue a delayed autosuspend request. If the device
1069 * _has_ been idle for long enough and the reschedule flag is set,
1070 * likewise queue a delayed (1 second) autosuspend request.
1073 if (time_before(j
, suspend_time
))
1076 suspend_time
= j
+ HZ
;
1078 if (!timer_pending(&udev
->autosuspend
.timer
)) {
1079 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1080 round_jiffies_relative(suspend_time
- j
));
1089 static inline int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1094 #endif /* CONFIG_USB_SUSPEND */
1097 * usb_suspend_both - suspend a USB device and its interfaces
1098 * @udev: the usb_device to suspend
1099 * @msg: Power Management message describing this state transition
1101 * This is the central routine for suspending USB devices. It calls the
1102 * suspend methods for all the interface drivers in @udev and then calls
1103 * the suspend method for @udev itself. If an error occurs at any stage,
1104 * all the interfaces which were suspended are resumed so that they remain
1105 * in the same state as the device.
1107 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
1108 * checks first to make sure that neither the device itself or any of its
1109 * active interfaces is in use (pm_usage_cnt is greater than 0). If they
1110 * are, the autosuspend fails.
1112 * If the suspend succeeds, the routine recursively queues an autosuspend
1113 * request for @udev's parent device, thereby propagating the change up
1114 * the device tree. If all of the parent's children are now suspended,
1115 * the parent will autosuspend in turn.
1117 * The suspend method calls are subject to mutual exclusion under control
1118 * of @udev's pm_mutex. Many of these calls are also under the protection
1119 * of @udev's device lock (including all requests originating outside the
1120 * USB subsystem), but autosuspend requests generated by a child device or
1121 * interface driver may not be. Usbcore will insure that the method calls
1122 * do not arrive during bind, unbind, or reset operations. However, drivers
1123 * must be prepared to handle suspend calls arriving at unpredictable times.
1124 * The only way to block such calls is to do an autoresume (preventing
1125 * autosuspends) while holding @udev's device lock (preventing outside
1128 * The caller must hold @udev->pm_mutex.
1130 * This routine can run only in process context.
1132 static int usb_suspend_both(struct usb_device
*udev
, pm_message_t msg
)
1136 struct usb_interface
*intf
;
1137 struct usb_device
*parent
= udev
->parent
;
1139 if (udev
->state
== USB_STATE_NOTATTACHED
||
1140 udev
->state
== USB_STATE_SUSPENDED
)
1143 udev
->do_remote_wakeup
= device_may_wakeup(&udev
->dev
);
1145 if (udev
->auto_pm
) {
1146 status
= autosuspend_check(udev
, 0);
1151 /* Suspend all the interfaces and then udev itself */
1152 if (udev
->actconfig
) {
1153 for (; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1154 intf
= udev
->actconfig
->interface
[i
];
1155 status
= usb_suspend_interface(intf
, msg
);
1161 status
= usb_suspend_device(udev
, msg
);
1163 /* If the suspend failed, resume interfaces that did get suspended */
1166 intf
= udev
->actconfig
->interface
[i
];
1167 usb_resume_interface(intf
, 0);
1170 /* Try another autosuspend when the interfaces aren't busy */
1172 autosuspend_check(udev
, status
== -EBUSY
);
1174 /* If the suspend succeeded then prevent any more URB submissions,
1175 * flush any outstanding URBs, and propagate the suspend up the tree.
1178 cancel_delayed_work(&udev
->autosuspend
);
1179 udev
->can_submit
= 0;
1180 for (i
= 0; i
< 16; ++i
) {
1181 usb_hcd_flush_endpoint(udev
, udev
->ep_out
[i
]);
1182 usb_hcd_flush_endpoint(udev
, udev
->ep_in
[i
]);
1185 /* If this is just a FREEZE or a PRETHAW, udev might
1186 * not really be suspended. Only true suspends get
1187 * propagated up the device tree.
1189 if (parent
&& udev
->state
== USB_STATE_SUSPENDED
)
1190 usb_autosuspend_device(parent
);
1194 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1199 * usb_resume_both - resume a USB device and its interfaces
1200 * @udev: the usb_device to resume
1202 * This is the central routine for resuming USB devices. It calls the
1203 * the resume method for @udev and then calls the resume methods for all
1204 * the interface drivers in @udev.
1206 * Before starting the resume, the routine calls itself recursively for
1207 * the parent device of @udev, thereby propagating the change up the device
1208 * tree and assuring that @udev will be able to resume. If the parent is
1209 * unable to resume successfully, the routine fails.
1211 * The resume method calls are subject to mutual exclusion under control
1212 * of @udev's pm_mutex. Many of these calls are also under the protection
1213 * of @udev's device lock (including all requests originating outside the
1214 * USB subsystem), but autoresume requests generated by a child device or
1215 * interface driver may not be. Usbcore will insure that the method calls
1216 * do not arrive during bind, unbind, or reset operations. However, drivers
1217 * must be prepared to handle resume calls arriving at unpredictable times.
1218 * The only way to block such calls is to do an autoresume (preventing
1219 * other autoresumes) while holding @udev's device lock (preventing outside
1222 * The caller must hold @udev->pm_mutex.
1224 * This routine can run only in process context.
1226 static int usb_resume_both(struct usb_device
*udev
)
1230 struct usb_interface
*intf
;
1231 struct usb_device
*parent
= udev
->parent
;
1233 cancel_delayed_work(&udev
->autosuspend
);
1234 if (udev
->state
== USB_STATE_NOTATTACHED
) {
1238 udev
->can_submit
= 1;
1240 /* Propagate the resume up the tree, if necessary */
1241 if (udev
->state
== USB_STATE_SUSPENDED
) {
1242 if (udev
->auto_pm
&& udev
->autoresume_disabled
) {
1247 status
= usb_autoresume_device(parent
);
1249 status
= usb_resume_device(udev
);
1250 if (status
|| udev
->state
==
1251 USB_STATE_NOTATTACHED
) {
1252 usb_autosuspend_device(parent
);
1254 /* It's possible usb_resume_device()
1255 * failed after the port was
1256 * unsuspended, causing udev to be
1257 * logically disconnected. We don't
1258 * want usb_disconnect() to autosuspend
1259 * the parent again, so tell it that
1260 * udev disconnected while still
1263 USB_STATE_NOTATTACHED
)
1264 udev
->discon_suspended
= 1;
1269 /* We can't progagate beyond the USB subsystem,
1270 * so if a root hub's controller is suspended
1271 * then we're stuck. */
1272 status
= usb_resume_device(udev
);
1274 } else if (udev
->reset_resume
)
1275 status
= usb_resume_device(udev
);
1277 if (status
== 0 && udev
->actconfig
) {
1278 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1279 intf
= udev
->actconfig
->interface
[i
];
1280 usb_resume_interface(intf
, udev
->reset_resume
);
1285 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1287 udev
->reset_resume
= 0;
1291 #ifdef CONFIG_USB_SUSPEND
1293 /* Internal routine to adjust a device's usage counter and change
1294 * its autosuspend state.
1296 static int usb_autopm_do_device(struct usb_device
*udev
, int inc_usage_cnt
)
1302 udev
->pm_usage_cnt
+= inc_usage_cnt
;
1303 WARN_ON(udev
->pm_usage_cnt
< 0);
1305 udev
->last_busy
= jiffies
;
1306 if (inc_usage_cnt
>= 0 && udev
->pm_usage_cnt
> 0) {
1307 if (udev
->state
== USB_STATE_SUSPENDED
)
1308 status
= usb_resume_both(udev
);
1310 udev
->pm_usage_cnt
-= inc_usage_cnt
;
1311 else if (inc_usage_cnt
)
1312 udev
->last_busy
= jiffies
;
1313 } else if (inc_usage_cnt
<= 0 && udev
->pm_usage_cnt
<= 0) {
1314 status
= usb_suspend_both(udev
, PMSG_SUSPEND
);
1316 usb_pm_unlock(udev
);
1320 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1321 void usb_autosuspend_work(struct work_struct
*work
)
1323 struct usb_device
*udev
=
1324 container_of(work
, struct usb_device
, autosuspend
.work
);
1326 usb_autopm_do_device(udev
, 0);
1330 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1331 * @udev: the usb_device to autosuspend
1333 * This routine should be called when a core subsystem is finished using
1334 * @udev and wants to allow it to autosuspend. Examples would be when
1335 * @udev's device file in usbfs is closed or after a configuration change.
1337 * @udev's usage counter is decremented. If it or any of the usage counters
1338 * for an active interface is greater than 0, no autosuspend request will be
1339 * queued. (If an interface driver does not support autosuspend then its
1340 * usage counter is permanently positive.) Furthermore, if an interface
1341 * driver requires remote-wakeup capability during autosuspend but remote
1342 * wakeup is disabled, the autosuspend will fail.
1344 * Often the caller will hold @udev's device lock, but this is not
1347 * This routine can run only in process context.
1349 void usb_autosuspend_device(struct usb_device
*udev
)
1353 status
= usb_autopm_do_device(udev
, -1);
1354 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1355 __func__
, udev
->pm_usage_cnt
);
1359 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1360 * @udev: the usb_device to autosuspend
1362 * This routine should be called when a core subsystem thinks @udev may
1363 * be ready to autosuspend.
1365 * @udev's usage counter left unchanged. If it or any of the usage counters
1366 * for an active interface is greater than 0, or autosuspend is not allowed
1367 * for any other reason, no autosuspend request will be queued.
1369 * This routine can run only in process context.
1371 void usb_try_autosuspend_device(struct usb_device
*udev
)
1373 usb_autopm_do_device(udev
, 0);
1374 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1375 __func__
, udev
->pm_usage_cnt
);
1379 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1380 * @udev: the usb_device to autoresume
1382 * This routine should be called when a core subsystem wants to use @udev
1383 * and needs to guarantee that it is not suspended. No autosuspend will
1384 * occur until usb_autosuspend_device is called. (Note that this will not
1385 * prevent suspend events originating in the PM core.) Examples would be
1386 * when @udev's device file in usbfs is opened or when a remote-wakeup
1387 * request is received.
1389 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1390 * However if the autoresume fails then the usage counter is re-decremented.
1392 * Often the caller will hold @udev's device lock, but this is not
1393 * necessary (and attempting it might cause deadlock).
1395 * This routine can run only in process context.
1397 int usb_autoresume_device(struct usb_device
*udev
)
1401 status
= usb_autopm_do_device(udev
, 1);
1402 dev_vdbg(&udev
->dev
, "%s: status %d cnt %d\n",
1403 __func__
, status
, udev
->pm_usage_cnt
);
1407 /* Internal routine to adjust an interface's usage counter and change
1408 * its device's autosuspend state.
1410 static int usb_autopm_do_interface(struct usb_interface
*intf
,
1413 struct usb_device
*udev
= interface_to_usbdev(intf
);
1417 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1421 intf
->pm_usage_cnt
+= inc_usage_cnt
;
1422 udev
->last_busy
= jiffies
;
1423 if (inc_usage_cnt
>= 0 && intf
->pm_usage_cnt
> 0) {
1424 if (udev
->state
== USB_STATE_SUSPENDED
)
1425 status
= usb_resume_both(udev
);
1427 intf
->pm_usage_cnt
-= inc_usage_cnt
;
1429 udev
->last_busy
= jiffies
;
1430 } else if (inc_usage_cnt
<= 0 && intf
->pm_usage_cnt
<= 0) {
1431 status
= usb_suspend_both(udev
, PMSG_SUSPEND
);
1434 usb_pm_unlock(udev
);
1439 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1440 * @intf: the usb_interface whose counter should be decremented
1442 * This routine should be called by an interface driver when it is
1443 * finished using @intf and wants to allow it to autosuspend. A typical
1444 * example would be a character-device driver when its device file is
1447 * The routine decrements @intf's usage counter. When the counter reaches
1448 * 0, a delayed autosuspend request for @intf's device is queued. When
1449 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1450 * the other usage counters for the sibling interfaces and @intf's
1451 * usb_device, the device and all its interfaces will be autosuspended.
1453 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1454 * core will not change its value other than the increment and decrement
1455 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1456 * may use this simple counter-oriented discipline or may set the value
1459 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1460 * take place only if the device's remote-wakeup facility is enabled.
1462 * Suspend method calls queued by this routine can arrive at any time
1463 * while @intf is resumed and its usage counter is equal to 0. They are
1464 * not protected by the usb_device's lock but only by its pm_mutex.
1465 * Drivers must provide their own synchronization.
1467 * This routine can run only in process context.
1469 void usb_autopm_put_interface(struct usb_interface
*intf
)
1473 status
= usb_autopm_do_interface(intf
, -1);
1474 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1475 __func__
, status
, intf
->pm_usage_cnt
);
1477 EXPORT_SYMBOL_GPL(usb_autopm_put_interface
);
1480 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1481 * @intf: the usb_interface whose counter should be incremented
1483 * This routine should be called by an interface driver when it wants to
1484 * use @intf and needs to guarantee that it is not suspended. In addition,
1485 * the routine prevents @intf from being autosuspended subsequently. (Note
1486 * that this will not prevent suspend events originating in the PM core.)
1487 * This prevention will persist until usb_autopm_put_interface() is called
1488 * or @intf is unbound. A typical example would be a character-device
1489 * driver when its device file is opened.
1492 * The routine increments @intf's usage counter. (However if the
1493 * autoresume fails then the counter is re-decremented.) So long as the
1494 * counter is greater than 0, autosuspend will not be allowed for @intf
1495 * or its usb_device. When the driver is finished using @intf it should
1496 * call usb_autopm_put_interface() to decrement the usage counter and
1497 * queue a delayed autosuspend request (if the counter is <= 0).
1500 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1501 * core will not change its value other than the increment and decrement
1502 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1503 * may use this simple counter-oriented discipline or may set the value
1506 * Resume method calls generated by this routine can arrive at any time
1507 * while @intf is suspended. They are not protected by the usb_device's
1508 * lock but only by its pm_mutex. Drivers must provide their own
1511 * This routine can run only in process context.
1513 int usb_autopm_get_interface(struct usb_interface
*intf
)
1517 status
= usb_autopm_do_interface(intf
, 1);
1518 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1519 __func__
, status
, intf
->pm_usage_cnt
);
1522 EXPORT_SYMBOL_GPL(usb_autopm_get_interface
);
1525 * usb_autopm_set_interface - set a USB interface's autosuspend state
1526 * @intf: the usb_interface whose state should be set
1528 * This routine sets the autosuspend state of @intf's device according
1529 * to @intf's usage counter, which the caller must have set previously.
1530 * If the counter is <= 0, the device is autosuspended (if it isn't
1531 * already suspended and if nothing else prevents the autosuspend). If
1532 * the counter is > 0, the device is autoresumed (if it isn't already
1535 int usb_autopm_set_interface(struct usb_interface
*intf
)
1539 status
= usb_autopm_do_interface(intf
, 0);
1540 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1541 __func__
, status
, intf
->pm_usage_cnt
);
1544 EXPORT_SYMBOL_GPL(usb_autopm_set_interface
);
1548 void usb_autosuspend_work(struct work_struct
*work
)
1551 #endif /* CONFIG_USB_SUSPEND */
1554 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1555 * @udev: the usb_device to suspend
1556 * @msg: Power Management message describing this state transition
1558 * This routine handles external suspend requests: ones not generated
1559 * internally by a USB driver (autosuspend) but rather coming from the user
1560 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1561 * out regardless of @udev's usage counter or those of its interfaces,
1562 * and regardless of whether or not remote wakeup is enabled. Of course,
1563 * interface drivers still have the option of failing the suspend (if
1564 * there are unsuspended children, for example).
1566 * The caller must hold @udev's device lock.
1568 int usb_external_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
1572 do_unbind_rebind(udev
, DO_UNBIND
);
1575 status
= usb_suspend_both(udev
, msg
);
1576 usb_pm_unlock(udev
);
1581 * usb_external_resume_device - external resume of a USB device and its interfaces
1582 * @udev: the usb_device to resume
1584 * This routine handles external resume requests: ones not generated
1585 * internally by a USB driver (autoresume) but rather coming from the user
1586 * (via sysfs), the PM core (system resume), or the device itself (remote
1587 * wakeup). @udev's usage counter is unaffected.
1589 * The caller must hold @udev's device lock.
1591 int usb_external_resume_device(struct usb_device
*udev
)
1597 status
= usb_resume_both(udev
);
1598 udev
->last_busy
= jiffies
;
1599 usb_pm_unlock(udev
);
1600 do_unbind_rebind(udev
, DO_REBIND
);
1602 /* Now that the device is awake, we can start trying to autosuspend
1605 usb_try_autosuspend_device(udev
);
1609 static int usb_suspend(struct device
*dev
, pm_message_t message
)
1611 struct usb_device
*udev
;
1613 if (!is_usb_device(dev
)) /* Ignore PM for interfaces */
1615 udev
= to_usb_device(dev
);
1617 /* If udev is already suspended, we can skip this suspend and
1618 * we should also skip the upcoming system resume. High-speed
1619 * root hubs are an exception; they need to resume whenever the
1620 * system wakes up in order for USB-PERSIST port handover to work
1623 if (udev
->state
== USB_STATE_SUSPENDED
) {
1624 if (udev
->parent
|| udev
->speed
!= USB_SPEED_HIGH
)
1625 udev
->skip_sys_resume
= 1;
1629 udev
->skip_sys_resume
= 0;
1630 return usb_external_suspend_device(udev
, message
);
1633 static int usb_resume(struct device
*dev
)
1635 struct usb_device
*udev
;
1637 if (!is_usb_device(dev
)) /* Ignore PM for interfaces */
1639 udev
= to_usb_device(dev
);
1641 /* If udev->skip_sys_resume is set then udev was already suspended
1642 * when the system sleep started, so we don't want to resume it
1643 * during this system wakeup.
1645 if (udev
->skip_sys_resume
)
1647 return usb_external_resume_device(udev
);
1652 #define usb_suspend NULL
1653 #define usb_resume NULL
1655 #endif /* CONFIG_PM */
1657 struct bus_type usb_bus_type
= {
1659 .match
= usb_device_match
,
1660 .uevent
= usb_uevent
,
1661 .suspend
= usb_suspend
,
1662 .resume
= usb_resume
,