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
= to_usb_device(dev
);
160 dev_dbg(dev
, "%s\n", __func__
);
162 /* TODO: Add real matching code */
164 /* The device should always appear to be in use
165 * unless the driver suports autosuspend.
167 udev
->pm_usage_cnt
= !(udriver
->supports_autosuspend
);
169 error
= udriver
->probe(udev
);
173 /* called from driver core with dev locked */
174 static int usb_unbind_device(struct device
*dev
)
176 struct usb_device_driver
*udriver
= to_usb_device_driver(dev
->driver
);
178 udriver
->disconnect(to_usb_device(dev
));
183 * Cancel any pending scheduled resets
185 * [see usb_queue_reset_device()]
187 * Called after unconfiguring / when releasing interfaces. See
188 * comments in __usb_queue_reset_device() regarding
189 * udev->reset_running.
191 static void usb_cancel_queued_reset(struct usb_interface
*iface
)
193 if (iface
->reset_running
== 0)
194 cancel_work_sync(&iface
->reset_ws
);
197 /* called from driver core with dev locked */
198 static int usb_probe_interface(struct device
*dev
)
200 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
201 struct usb_interface
*intf
= to_usb_interface(dev
);
202 struct usb_device
*udev
= interface_to_usbdev(intf
);
203 const struct usb_device_id
*id
;
206 dev_dbg(dev
, "%s\n", __func__
);
208 intf
->needs_binding
= 0;
210 if (usb_device_is_owned(udev
))
213 if (udev
->authorized
== 0) {
214 dev_err(&intf
->dev
, "Device is not authorized for usage\n");
218 id
= usb_match_id(intf
, driver
->id_table
);
220 id
= usb_match_dynamic_id(intf
, driver
);
222 dev_dbg(dev
, "%s - got id\n", __func__
);
224 error
= usb_autoresume_device(udev
);
228 /* Interface "power state" doesn't correspond to any hardware
229 * state whatsoever. We use it to record when it's bound to
230 * a driver that may start I/0: it's not frozen/quiesced.
233 intf
->condition
= USB_INTERFACE_BINDING
;
235 /* The interface should always appear to be in use
236 * unless the driver suports autosuspend.
238 atomic_set(&intf
->pm_usage_cnt
, !driver
->supports_autosuspend
);
240 /* Carry out a deferred switch to altsetting 0 */
241 if (intf
->needs_altsetting0
) {
242 error
= usb_set_interface(udev
, intf
->altsetting
[0].
243 desc
.bInterfaceNumber
, 0);
247 intf
->needs_altsetting0
= 0;
250 error
= driver
->probe(intf
, id
);
254 intf
->condition
= USB_INTERFACE_BOUND
;
255 usb_autosuspend_device(udev
);
262 intf
->needs_remote_wakeup
= 0;
263 intf
->condition
= USB_INTERFACE_UNBOUND
;
264 usb_cancel_queued_reset(intf
);
265 usb_autosuspend_device(udev
);
269 /* called from driver core with dev locked */
270 static int usb_unbind_interface(struct device
*dev
)
272 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
273 struct usb_interface
*intf
= to_usb_interface(dev
);
274 struct usb_device
*udev
;
277 intf
->condition
= USB_INTERFACE_UNBINDING
;
279 /* Autoresume for set_interface call below */
280 udev
= interface_to_usbdev(intf
);
281 error
= usb_autoresume_device(udev
);
283 /* Terminate all URBs for this interface unless the driver
284 * supports "soft" unbinding.
286 if (!driver
->soft_unbind
)
287 usb_disable_interface(udev
, intf
, false);
289 driver
->disconnect(intf
);
290 usb_cancel_queued_reset(intf
);
292 /* Reset other interface state.
293 * We cannot do a Set-Interface if the device is suspended or
294 * if it is prepared for a system sleep (since installing a new
295 * altsetting means creating new endpoint device entries).
296 * When either of these happens, defer the Set-Interface.
298 if (intf
->cur_altsetting
->desc
.bAlternateSetting
== 0) {
299 /* Already in altsetting 0 so skip Set-Interface.
300 * Just re-enable it without affecting the endpoint toggles.
302 usb_enable_interface(udev
, intf
, false);
303 } else if (!error
&& intf
->dev
.power
.status
== DPM_ON
) {
304 r
= usb_set_interface(udev
, intf
->altsetting
[0].
305 desc
.bInterfaceNumber
, 0);
307 intf
->needs_altsetting0
= 1;
309 intf
->needs_altsetting0
= 1;
311 usb_set_intfdata(intf
, NULL
);
313 intf
->condition
= USB_INTERFACE_UNBOUND
;
315 intf
->needs_remote_wakeup
= 0;
318 usb_autosuspend_device(udev
);
324 * usb_driver_claim_interface - bind a driver to an interface
325 * @driver: the driver to be bound
326 * @iface: the interface to which it will be bound; must be in the
327 * usb device's active configuration
328 * @priv: driver data associated with that interface
330 * This is used by usb device drivers that need to claim more than one
331 * interface on a device when probing (audio and acm are current examples).
332 * No device driver should directly modify internal usb_interface or
333 * usb_device structure members.
335 * Few drivers should need to use this routine, since the most natural
336 * way to bind to an interface is to return the private data from
337 * the driver's probe() method.
339 * Callers must own the device lock, so driver probe() entries don't need
340 * extra locking, but other call contexts may need to explicitly claim that
343 int usb_driver_claim_interface(struct usb_driver
*driver
,
344 struct usb_interface
*iface
, void *priv
)
346 struct device
*dev
= &iface
->dev
;
347 struct usb_device
*udev
= interface_to_usbdev(iface
);
353 dev
->driver
= &driver
->drvwrap
.driver
;
354 usb_set_intfdata(iface
, priv
);
355 iface
->needs_binding
= 0;
358 iface
->condition
= USB_INTERFACE_BOUND
;
360 atomic_set(&iface
->pm_usage_cnt
, !driver
->supports_autosuspend
);
363 /* if interface was already added, bind now; else let
364 * the future device_add() bind it, bypassing probe()
366 if (device_is_registered(dev
))
367 retval
= device_bind_driver(dev
);
371 EXPORT_SYMBOL_GPL(usb_driver_claim_interface
);
374 * usb_driver_release_interface - unbind a driver from an interface
375 * @driver: the driver to be unbound
376 * @iface: the interface from which it will be unbound
378 * This can be used by drivers to release an interface without waiting
379 * for their disconnect() methods to be called. In typical cases this
380 * also causes the driver disconnect() method to be called.
382 * This call is synchronous, and may not be used in an interrupt context.
383 * Callers must own the device lock, so driver disconnect() entries don't
384 * need extra locking, but other call contexts may need to explicitly claim
387 void usb_driver_release_interface(struct usb_driver
*driver
,
388 struct usb_interface
*iface
)
390 struct device
*dev
= &iface
->dev
;
392 /* this should never happen, don't release something that's not ours */
393 if (!dev
->driver
|| dev
->driver
!= &driver
->drvwrap
.driver
)
396 /* don't release from within disconnect() */
397 if (iface
->condition
!= USB_INTERFACE_BOUND
)
399 iface
->condition
= USB_INTERFACE_UNBINDING
;
401 /* Release via the driver core only if the interface
402 * has already been registered
404 if (device_is_registered(dev
)) {
405 device_release_driver(dev
);
408 usb_unbind_interface(dev
);
413 EXPORT_SYMBOL_GPL(usb_driver_release_interface
);
415 /* returns 0 if no match, 1 if match */
416 int usb_match_device(struct usb_device
*dev
, const struct usb_device_id
*id
)
418 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
419 id
->idVendor
!= le16_to_cpu(dev
->descriptor
.idVendor
))
422 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_PRODUCT
) &&
423 id
->idProduct
!= le16_to_cpu(dev
->descriptor
.idProduct
))
426 /* No need to test id->bcdDevice_lo != 0, since 0 is never
427 greater than any unsigned number. */
428 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_LO
) &&
429 (id
->bcdDevice_lo
> le16_to_cpu(dev
->descriptor
.bcdDevice
)))
432 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_HI
) &&
433 (id
->bcdDevice_hi
< le16_to_cpu(dev
->descriptor
.bcdDevice
)))
436 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_CLASS
) &&
437 (id
->bDeviceClass
!= dev
->descriptor
.bDeviceClass
))
440 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_SUBCLASS
) &&
441 (id
->bDeviceSubClass
!= dev
->descriptor
.bDeviceSubClass
))
444 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_PROTOCOL
) &&
445 (id
->bDeviceProtocol
!= dev
->descriptor
.bDeviceProtocol
))
451 /* returns 0 if no match, 1 if match */
452 int usb_match_one_id(struct usb_interface
*interface
,
453 const struct usb_device_id
*id
)
455 struct usb_host_interface
*intf
;
456 struct usb_device
*dev
;
458 /* proc_connectinfo in devio.c may call us with id == NULL. */
462 intf
= interface
->cur_altsetting
;
463 dev
= interface_to_usbdev(interface
);
465 if (!usb_match_device(dev
, id
))
468 /* The interface class, subclass, and protocol should never be
469 * checked for a match if the device class is Vendor Specific,
470 * unless the match record specifies the Vendor ID. */
471 if (dev
->descriptor
.bDeviceClass
== USB_CLASS_VENDOR_SPEC
&&
472 !(id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
473 (id
->match_flags
& (USB_DEVICE_ID_MATCH_INT_CLASS
|
474 USB_DEVICE_ID_MATCH_INT_SUBCLASS
|
475 USB_DEVICE_ID_MATCH_INT_PROTOCOL
)))
478 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_CLASS
) &&
479 (id
->bInterfaceClass
!= intf
->desc
.bInterfaceClass
))
482 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_SUBCLASS
) &&
483 (id
->bInterfaceSubClass
!= intf
->desc
.bInterfaceSubClass
))
486 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_PROTOCOL
) &&
487 (id
->bInterfaceProtocol
!= intf
->desc
.bInterfaceProtocol
))
492 EXPORT_SYMBOL_GPL(usb_match_one_id
);
495 * usb_match_id - find first usb_device_id matching device or interface
496 * @interface: the interface of interest
497 * @id: array of usb_device_id structures, terminated by zero entry
499 * usb_match_id searches an array of usb_device_id's and returns
500 * the first one matching the device or interface, or null.
501 * This is used when binding (or rebinding) a driver to an interface.
502 * Most USB device drivers will use this indirectly, through the usb core,
503 * but some layered driver frameworks use it directly.
504 * These device tables are exported with MODULE_DEVICE_TABLE, through
505 * modutils, to support the driver loading functionality of USB hotplugging.
509 * The "match_flags" element in a usb_device_id controls which
510 * members are used. If the corresponding bit is set, the
511 * value in the device_id must match its corresponding member
512 * in the device or interface descriptor, or else the device_id
515 * "driver_info" is normally used only by device drivers,
516 * but you can create a wildcard "matches anything" usb_device_id
517 * as a driver's "modules.usbmap" entry if you provide an id with
518 * only a nonzero "driver_info" field. If you do this, the USB device
519 * driver's probe() routine should use additional intelligence to
520 * decide whether to bind to the specified interface.
522 * What Makes Good usb_device_id Tables:
524 * The match algorithm is very simple, so that intelligence in
525 * driver selection must come from smart driver id records.
526 * Unless you have good reasons to use another selection policy,
527 * provide match elements only in related groups, and order match
528 * specifiers from specific to general. Use the macros provided
529 * for that purpose if you can.
531 * The most specific match specifiers use device descriptor
532 * data. These are commonly used with product-specific matches;
533 * the USB_DEVICE macro lets you provide vendor and product IDs,
534 * and you can also match against ranges of product revisions.
535 * These are widely used for devices with application or vendor
536 * specific bDeviceClass values.
538 * Matches based on device class/subclass/protocol specifications
539 * are slightly more general; use the USB_DEVICE_INFO macro, or
540 * its siblings. These are used with single-function devices
541 * where bDeviceClass doesn't specify that each interface has
544 * Matches based on interface class/subclass/protocol are the
545 * most general; they let drivers bind to any interface on a
546 * multiple-function device. Use the USB_INTERFACE_INFO
547 * macro, or its siblings, to match class-per-interface style
548 * devices (as recorded in bInterfaceClass).
550 * Note that an entry created by USB_INTERFACE_INFO won't match
551 * any interface if the device class is set to Vendor-Specific.
552 * This is deliberate; according to the USB spec the meanings of
553 * the interface class/subclass/protocol for these devices are also
554 * vendor-specific, and hence matching against a standard product
555 * class wouldn't work anyway. If you really want to use an
556 * interface-based match for such a device, create a match record
557 * that also specifies the vendor ID. (Unforunately there isn't a
558 * standard macro for creating records like this.)
560 * Within those groups, remember that not all combinations are
561 * meaningful. For example, don't give a product version range
562 * without vendor and product IDs; or specify a protocol without
563 * its associated class and subclass.
565 const struct usb_device_id
*usb_match_id(struct usb_interface
*interface
,
566 const struct usb_device_id
*id
)
568 /* proc_connectinfo in devio.c may call us with id == NULL. */
572 /* It is important to check that id->driver_info is nonzero,
573 since an entry that is all zeroes except for a nonzero
574 id->driver_info is the way to create an entry that
575 indicates that the driver want to examine every
576 device and interface. */
577 for (; id
->idVendor
|| id
->idProduct
|| id
->bDeviceClass
||
578 id
->bInterfaceClass
|| id
->driver_info
; id
++) {
579 if (usb_match_one_id(interface
, id
))
585 EXPORT_SYMBOL_GPL(usb_match_id
);
587 static int usb_device_match(struct device
*dev
, struct device_driver
*drv
)
589 /* devices and interfaces are handled separately */
590 if (is_usb_device(dev
)) {
592 /* interface drivers never match devices */
593 if (!is_usb_device_driver(drv
))
596 /* TODO: Add real matching code */
599 } else if (is_usb_interface(dev
)) {
600 struct usb_interface
*intf
;
601 struct usb_driver
*usb_drv
;
602 const struct usb_device_id
*id
;
604 /* device drivers never match interfaces */
605 if (is_usb_device_driver(drv
))
608 intf
= to_usb_interface(dev
);
609 usb_drv
= to_usb_driver(drv
);
611 id
= usb_match_id(intf
, usb_drv
->id_table
);
615 id
= usb_match_dynamic_id(intf
, usb_drv
);
623 #ifdef CONFIG_HOTPLUG
624 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
626 struct usb_device
*usb_dev
;
628 if (is_usb_device(dev
)) {
629 usb_dev
= to_usb_device(dev
);
630 } else if (is_usb_interface(dev
)) {
631 struct usb_interface
*intf
= to_usb_interface(dev
);
633 usb_dev
= interface_to_usbdev(intf
);
638 if (usb_dev
->devnum
< 0) {
639 /* driver is often null here; dev_dbg() would oops */
640 pr_debug("usb %s: already deleted?\n", dev_name(dev
));
644 pr_debug("usb %s: bus removed?\n", dev_name(dev
));
648 #ifdef CONFIG_USB_DEVICEFS
649 /* If this is available, userspace programs can directly read
650 * all the device descriptors we don't tell them about. Or
651 * act as usermode drivers.
653 if (add_uevent_var(env
, "DEVICE=/proc/bus/usb/%03d/%03d",
654 usb_dev
->bus
->busnum
, usb_dev
->devnum
))
658 /* per-device configurations are common */
659 if (add_uevent_var(env
, "PRODUCT=%x/%x/%x",
660 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
661 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
662 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
)))
665 /* class-based driver binding models */
666 if (add_uevent_var(env
, "TYPE=%d/%d/%d",
667 usb_dev
->descriptor
.bDeviceClass
,
668 usb_dev
->descriptor
.bDeviceSubClass
,
669 usb_dev
->descriptor
.bDeviceProtocol
))
677 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
681 #endif /* CONFIG_HOTPLUG */
684 * usb_register_device_driver - register a USB device (not interface) driver
685 * @new_udriver: USB operations for the device driver
686 * @owner: module owner of this driver.
688 * Registers a USB device driver with the USB core. The list of
689 * unattached devices will be rescanned whenever a new driver is
690 * added, allowing the new driver to attach to any recognized devices.
691 * Returns a negative error code on failure and 0 on success.
693 int usb_register_device_driver(struct usb_device_driver
*new_udriver
,
694 struct module
*owner
)
701 new_udriver
->drvwrap
.for_devices
= 1;
702 new_udriver
->drvwrap
.driver
.name
= (char *) new_udriver
->name
;
703 new_udriver
->drvwrap
.driver
.bus
= &usb_bus_type
;
704 new_udriver
->drvwrap
.driver
.probe
= usb_probe_device
;
705 new_udriver
->drvwrap
.driver
.remove
= usb_unbind_device
;
706 new_udriver
->drvwrap
.driver
.owner
= owner
;
708 retval
= driver_register(&new_udriver
->drvwrap
.driver
);
711 pr_info("%s: registered new device driver %s\n",
712 usbcore_name
, new_udriver
->name
);
713 usbfs_update_special();
715 printk(KERN_ERR
"%s: error %d registering device "
717 usbcore_name
, retval
, new_udriver
->name
);
722 EXPORT_SYMBOL_GPL(usb_register_device_driver
);
725 * usb_deregister_device_driver - unregister a USB device (not interface) driver
726 * @udriver: USB operations of the device driver to unregister
727 * Context: must be able to sleep
729 * Unlinks the specified driver from the internal USB driver list.
731 void usb_deregister_device_driver(struct usb_device_driver
*udriver
)
733 pr_info("%s: deregistering device driver %s\n",
734 usbcore_name
, udriver
->name
);
736 driver_unregister(&udriver
->drvwrap
.driver
);
737 usbfs_update_special();
739 EXPORT_SYMBOL_GPL(usb_deregister_device_driver
);
742 * usb_register_driver - register a USB interface driver
743 * @new_driver: USB operations for the interface driver
744 * @owner: module owner of this driver.
745 * @mod_name: module name string
747 * Registers a USB interface driver with the USB core. The list of
748 * unattached interfaces will be rescanned whenever a new driver is
749 * added, allowing the new driver to attach to any recognized interfaces.
750 * Returns a negative error code on failure and 0 on success.
752 * NOTE: if you want your driver to use the USB major number, you must call
753 * usb_register_dev() to enable that functionality. This function no longer
754 * takes care of that.
756 int usb_register_driver(struct usb_driver
*new_driver
, struct module
*owner
,
757 const char *mod_name
)
764 new_driver
->drvwrap
.for_devices
= 0;
765 new_driver
->drvwrap
.driver
.name
= (char *) new_driver
->name
;
766 new_driver
->drvwrap
.driver
.bus
= &usb_bus_type
;
767 new_driver
->drvwrap
.driver
.probe
= usb_probe_interface
;
768 new_driver
->drvwrap
.driver
.remove
= usb_unbind_interface
;
769 new_driver
->drvwrap
.driver
.owner
= owner
;
770 new_driver
->drvwrap
.driver
.mod_name
= mod_name
;
771 spin_lock_init(&new_driver
->dynids
.lock
);
772 INIT_LIST_HEAD(&new_driver
->dynids
.list
);
774 retval
= driver_register(&new_driver
->drvwrap
.driver
);
777 pr_info("%s: registered new interface driver %s\n",
778 usbcore_name
, new_driver
->name
);
779 usbfs_update_special();
780 usb_create_newid_file(new_driver
);
782 printk(KERN_ERR
"%s: error %d registering interface "
784 usbcore_name
, retval
, new_driver
->name
);
789 EXPORT_SYMBOL_GPL(usb_register_driver
);
792 * usb_deregister - unregister a USB interface driver
793 * @driver: USB operations of the interface driver to unregister
794 * Context: must be able to sleep
796 * Unlinks the specified driver from the internal USB driver list.
798 * NOTE: If you called usb_register_dev(), you still need to call
799 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
800 * this * call will no longer do it for you.
802 void usb_deregister(struct usb_driver
*driver
)
804 pr_info("%s: deregistering interface driver %s\n",
805 usbcore_name
, driver
->name
);
807 usb_remove_newid_file(driver
);
808 usb_free_dynids(driver
);
809 driver_unregister(&driver
->drvwrap
.driver
);
811 usbfs_update_special();
813 EXPORT_SYMBOL_GPL(usb_deregister
);
815 /* Forced unbinding of a USB interface driver, either because
816 * it doesn't support pre_reset/post_reset/reset_resume or
817 * because it doesn't support suspend/resume.
819 * The caller must hold @intf's device's lock, but not its pm_mutex
820 * and not @intf->dev.sem.
822 void usb_forced_unbind_intf(struct usb_interface
*intf
)
824 struct usb_driver
*driver
= to_usb_driver(intf
->dev
.driver
);
826 dev_dbg(&intf
->dev
, "forced unbind\n");
827 usb_driver_release_interface(driver
, intf
);
829 /* Mark the interface for later rebinding */
830 intf
->needs_binding
= 1;
833 /* Delayed forced unbinding of a USB interface driver and scan
836 * The caller must hold @intf's device's lock, but not its pm_mutex
837 * and not @intf->dev.sem.
839 * Note: Rebinds will be skipped if a system sleep transition is in
840 * progress and the PM "complete" callback hasn't occurred yet.
842 void usb_rebind_intf(struct usb_interface
*intf
)
846 /* Delayed unbind of an existing driver */
847 if (intf
->dev
.driver
) {
848 struct usb_driver
*driver
=
849 to_usb_driver(intf
->dev
.driver
);
851 dev_dbg(&intf
->dev
, "forced unbind\n");
852 usb_driver_release_interface(driver
, intf
);
855 /* Try to rebind the interface */
856 if (intf
->dev
.power
.status
== DPM_ON
) {
857 intf
->needs_binding
= 0;
858 rc
= device_attach(&intf
->dev
);
860 dev_warn(&intf
->dev
, "rebind failed: %d\n", rc
);
869 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
870 * or rebind interfaces that have been unbound, according to @action.
872 * The caller must hold @udev's device lock.
874 static void do_unbind_rebind(struct usb_device
*udev
, int action
)
876 struct usb_host_config
*config
;
878 struct usb_interface
*intf
;
879 struct usb_driver
*drv
;
881 config
= udev
->actconfig
;
883 for (i
= 0; i
< config
->desc
.bNumInterfaces
; ++i
) {
884 intf
= config
->interface
[i
];
887 if (intf
->dev
.driver
) {
888 drv
= to_usb_driver(intf
->dev
.driver
);
889 if (!drv
->suspend
|| !drv
->resume
)
890 usb_forced_unbind_intf(intf
);
894 if (intf
->needs_binding
)
895 usb_rebind_intf(intf
);
902 /* Caller has locked udev's pm_mutex */
903 static int usb_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
905 struct usb_device_driver
*udriver
;
908 if (udev
->state
== USB_STATE_NOTATTACHED
||
909 udev
->state
== USB_STATE_SUSPENDED
)
912 /* For devices that don't have a driver, we do a generic suspend. */
913 if (udev
->dev
.driver
)
914 udriver
= to_usb_device_driver(udev
->dev
.driver
);
916 udev
->do_remote_wakeup
= 0;
917 udriver
= &usb_generic_driver
;
919 status
= udriver
->suspend(udev
, msg
);
922 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
926 /* Caller has locked udev's pm_mutex */
927 static int usb_resume_device(struct usb_device
*udev
, pm_message_t msg
)
929 struct usb_device_driver
*udriver
;
932 if (udev
->state
== USB_STATE_NOTATTACHED
)
935 /* Can't resume it if it doesn't have a driver. */
936 if (udev
->dev
.driver
== NULL
) {
941 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
)
942 udev
->reset_resume
= 1;
944 udriver
= to_usb_device_driver(udev
->dev
.driver
);
945 status
= udriver
->resume(udev
, msg
);
948 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
950 udev
->autoresume_disabled
= 0;
954 /* Caller has locked intf's usb_device's pm mutex */
955 static int usb_suspend_interface(struct usb_device
*udev
,
956 struct usb_interface
*intf
, pm_message_t msg
)
958 struct usb_driver
*driver
;
961 /* with no hardware, USB interfaces only use FREEZE and ON states */
962 if (udev
->state
== USB_STATE_NOTATTACHED
|| !is_active(intf
))
965 /* This can happen; see usb_driver_release_interface() */
966 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
968 driver
= to_usb_driver(intf
->dev
.driver
);
970 if (driver
->suspend
) {
971 status
= driver
->suspend(intf
, msg
);
974 else if (!(msg
.event
& PM_EVENT_AUTO
))
975 dev_err(&intf
->dev
, "%s error %d\n",
978 /* Later we will unbind the driver and reprobe */
979 intf
->needs_binding
= 1;
980 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
981 "suspend", driver
->name
);
986 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
990 /* Caller has locked intf's usb_device's pm_mutex */
991 static int usb_resume_interface(struct usb_device
*udev
,
992 struct usb_interface
*intf
, pm_message_t msg
, int reset_resume
)
994 struct usb_driver
*driver
;
997 if (udev
->state
== USB_STATE_NOTATTACHED
|| is_active(intf
))
1000 /* Don't let autoresume interfere with unbinding */
1001 if (intf
->condition
== USB_INTERFACE_UNBINDING
)
1004 /* Can't resume it if it doesn't have a driver. */
1005 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
1007 /* Carry out a deferred switch to altsetting 0 */
1008 if (intf
->needs_altsetting0
&&
1009 intf
->dev
.power
.status
== DPM_ON
) {
1010 usb_set_interface(udev
, intf
->altsetting
[0].
1011 desc
.bInterfaceNumber
, 0);
1012 intf
->needs_altsetting0
= 0;
1017 /* Don't resume if the interface is marked for rebinding */
1018 if (intf
->needs_binding
)
1020 driver
= to_usb_driver(intf
->dev
.driver
);
1023 if (driver
->reset_resume
) {
1024 status
= driver
->reset_resume(intf
);
1026 dev_err(&intf
->dev
, "%s error %d\n",
1027 "reset_resume", status
);
1029 intf
->needs_binding
= 1;
1030 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1031 "reset_resume", driver
->name
);
1034 if (driver
->resume
) {
1035 status
= driver
->resume(intf
);
1037 dev_err(&intf
->dev
, "%s error %d\n",
1040 intf
->needs_binding
= 1;
1041 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1042 "resume", driver
->name
);
1047 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
1048 if (status
== 0 && intf
->condition
== USB_INTERFACE_BOUND
)
1051 /* Later we will unbind the driver and/or reprobe, if necessary */
1055 #ifdef CONFIG_USB_SUSPEND
1057 /* Internal routine to check whether we may autosuspend a device. */
1058 static int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1061 struct usb_interface
*intf
;
1062 unsigned long suspend_time
, j
;
1064 /* For autosuspend, fail fast if anything is in use or autosuspend
1065 * is disabled. Also fail if any interfaces require remote wakeup
1066 * but it isn't available.
1068 if (udev
->pm_usage_cnt
> 0)
1070 if (udev
->autosuspend_delay
< 0 || udev
->autosuspend_disabled
)
1073 suspend_time
= udev
->last_busy
+ udev
->autosuspend_delay
;
1074 if (udev
->actconfig
) {
1075 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1076 intf
= udev
->actconfig
->interface
[i
];
1077 if (!is_active(intf
))
1079 if (atomic_read(&intf
->pm_usage_cnt
) > 0)
1081 if (intf
->needs_remote_wakeup
&&
1082 !udev
->do_remote_wakeup
) {
1083 dev_dbg(&udev
->dev
, "remote wakeup needed "
1084 "for autosuspend\n");
1088 /* Don't allow autosuspend if the device will need
1089 * a reset-resume and any of its interface drivers
1090 * doesn't include support.
1092 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
) {
1093 struct usb_driver
*driver
;
1095 driver
= to_usb_driver(intf
->dev
.driver
);
1096 if (!driver
->reset_resume
||
1097 intf
->needs_remote_wakeup
)
1103 /* If everything is okay but the device hasn't been idle for long
1104 * enough, queue a delayed autosuspend request. If the device
1105 * _has_ been idle for long enough and the reschedule flag is set,
1106 * likewise queue a delayed (1 second) autosuspend request.
1109 if (time_before(j
, suspend_time
))
1112 suspend_time
= j
+ HZ
;
1114 if (!timer_pending(&udev
->autosuspend
.timer
)) {
1115 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1116 round_jiffies_up_relative(suspend_time
- j
));
1125 static inline int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1130 #endif /* CONFIG_USB_SUSPEND */
1133 * usb_suspend_both - suspend a USB device and its interfaces
1134 * @udev: the usb_device to suspend
1135 * @msg: Power Management message describing this state transition
1137 * This is the central routine for suspending USB devices. It calls the
1138 * suspend methods for all the interface drivers in @udev and then calls
1139 * the suspend method for @udev itself. If an error occurs at any stage,
1140 * all the interfaces which were suspended are resumed so that they remain
1141 * in the same state as the device.
1143 * If an autosuspend is in progress the routine checks first to make sure
1144 * that neither the device itself or any of its active interfaces is in use
1145 * (pm_usage_cnt is greater than 0). If they are, the autosuspend fails.
1147 * If the suspend succeeds, the routine recursively queues an autosuspend
1148 * request for @udev's parent device, thereby propagating the change up
1149 * the device tree. If all of the parent's children are now suspended,
1150 * the parent will autosuspend in turn.
1152 * The suspend method calls are subject to mutual exclusion under control
1153 * of @udev's pm_mutex. Many of these calls are also under the protection
1154 * of @udev's device lock (including all requests originating outside the
1155 * USB subsystem), but autosuspend requests generated by a child device or
1156 * interface driver may not be. Usbcore will insure that the method calls
1157 * do not arrive during bind, unbind, or reset operations. However, drivers
1158 * must be prepared to handle suspend calls arriving at unpredictable times.
1159 * The only way to block such calls is to do an autoresume (preventing
1160 * autosuspends) while holding @udev's device lock (preventing outside
1163 * The caller must hold @udev->pm_mutex.
1165 * This routine can run only in process context.
1167 static int usb_suspend_both(struct usb_device
*udev
, pm_message_t msg
)
1171 struct usb_interface
*intf
;
1172 struct usb_device
*parent
= udev
->parent
;
1174 if (udev
->state
== USB_STATE_NOTATTACHED
||
1175 udev
->state
== USB_STATE_SUSPENDED
)
1178 if (msg
.event
& PM_EVENT_AUTO
) {
1179 udev
->do_remote_wakeup
= device_may_wakeup(&udev
->dev
);
1180 status
= autosuspend_check(udev
, 0);
1185 /* Suspend all the interfaces and then udev itself */
1186 if (udev
->actconfig
) {
1187 for (; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1188 intf
= udev
->actconfig
->interface
[i
];
1189 status
= usb_suspend_interface(udev
, intf
, msg
);
1195 status
= usb_suspend_device(udev
, msg
);
1197 /* If the suspend failed, resume interfaces that did get suspended */
1201 msg2
.event
= msg
.event
^ (PM_EVENT_SUSPEND
| PM_EVENT_RESUME
);
1203 intf
= udev
->actconfig
->interface
[i
];
1204 usb_resume_interface(udev
, intf
, msg2
, 0);
1207 /* Try another autosuspend when the interfaces aren't busy */
1208 if (msg
.event
& PM_EVENT_AUTO
)
1209 autosuspend_check(udev
, status
== -EBUSY
);
1211 /* If the suspend succeeded then prevent any more URB submissions,
1212 * flush any outstanding URBs, and propagate the suspend up the tree.
1215 cancel_delayed_work(&udev
->autosuspend
);
1216 udev
->can_submit
= 0;
1217 for (i
= 0; i
< 16; ++i
) {
1218 usb_hcd_flush_endpoint(udev
, udev
->ep_out
[i
]);
1219 usb_hcd_flush_endpoint(udev
, udev
->ep_in
[i
]);
1222 /* If this is just a FREEZE or a PRETHAW, udev might
1223 * not really be suspended. Only true suspends get
1224 * propagated up the device tree.
1226 if (parent
&& udev
->state
== USB_STATE_SUSPENDED
)
1227 usb_autosuspend_device(parent
);
1231 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1236 * usb_resume_both - resume a USB device and its interfaces
1237 * @udev: the usb_device to resume
1238 * @msg: Power Management message describing this state transition
1240 * This is the central routine for resuming USB devices. It calls the
1241 * the resume method for @udev and then calls the resume methods for all
1242 * the interface drivers in @udev.
1244 * Before starting the resume, the routine calls itself recursively for
1245 * the parent device of @udev, thereby propagating the change up the device
1246 * tree and assuring that @udev will be able to resume. If the parent is
1247 * unable to resume successfully, the routine fails.
1249 * The resume method calls are subject to mutual exclusion under control
1250 * of @udev's pm_mutex. Many of these calls are also under the protection
1251 * of @udev's device lock (including all requests originating outside the
1252 * USB subsystem), but autoresume requests generated by a child device or
1253 * interface driver may not be. Usbcore will insure that the method calls
1254 * do not arrive during bind, unbind, or reset operations. However, drivers
1255 * must be prepared to handle resume calls arriving at unpredictable times.
1256 * The only way to block such calls is to do an autoresume (preventing
1257 * other autoresumes) while holding @udev's device lock (preventing outside
1260 * The caller must hold @udev->pm_mutex.
1262 * This routine can run only in process context.
1264 static int usb_resume_both(struct usb_device
*udev
, pm_message_t msg
)
1268 struct usb_interface
*intf
;
1269 struct usb_device
*parent
= udev
->parent
;
1271 cancel_delayed_work(&udev
->autosuspend
);
1272 if (udev
->state
== USB_STATE_NOTATTACHED
) {
1276 udev
->can_submit
= 1;
1278 /* Propagate the resume up the tree, if necessary */
1279 if (udev
->state
== USB_STATE_SUSPENDED
) {
1280 if ((msg
.event
& PM_EVENT_AUTO
) &&
1281 udev
->autoresume_disabled
) {
1286 status
= usb_autoresume_device(parent
);
1288 status
= usb_resume_device(udev
, msg
);
1289 if (status
|| udev
->state
==
1290 USB_STATE_NOTATTACHED
) {
1291 usb_autosuspend_device(parent
);
1293 /* It's possible usb_resume_device()
1294 * failed after the port was
1295 * unsuspended, causing udev to be
1296 * logically disconnected. We don't
1297 * want usb_disconnect() to autosuspend
1298 * the parent again, so tell it that
1299 * udev disconnected while still
1302 USB_STATE_NOTATTACHED
)
1303 udev
->discon_suspended
= 1;
1308 /* We can't progagate beyond the USB subsystem,
1309 * so if a root hub's controller is suspended
1310 * then we're stuck. */
1311 status
= usb_resume_device(udev
, msg
);
1313 } else if (udev
->reset_resume
)
1314 status
= usb_resume_device(udev
, msg
);
1316 if (status
== 0 && udev
->actconfig
) {
1317 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1318 intf
= udev
->actconfig
->interface
[i
];
1319 usb_resume_interface(udev
, intf
, msg
,
1320 udev
->reset_resume
);
1325 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1327 udev
->reset_resume
= 0;
1331 #ifdef CONFIG_USB_SUSPEND
1333 /* Internal routine to adjust a device's usage counter and change
1334 * its autosuspend state.
1336 static int usb_autopm_do_device(struct usb_device
*udev
, int inc_usage_cnt
)
1342 udev
->pm_usage_cnt
+= inc_usage_cnt
;
1343 WARN_ON(udev
->pm_usage_cnt
< 0);
1345 udev
->last_busy
= jiffies
;
1346 if (inc_usage_cnt
>= 0 && udev
->pm_usage_cnt
> 0) {
1347 if (udev
->state
== USB_STATE_SUSPENDED
)
1348 status
= usb_resume_both(udev
, PMSG_AUTO_RESUME
);
1350 udev
->pm_usage_cnt
-= inc_usage_cnt
;
1351 else if (inc_usage_cnt
)
1352 udev
->last_busy
= jiffies
;
1353 } else if (inc_usage_cnt
<= 0 && udev
->pm_usage_cnt
<= 0) {
1354 status
= usb_suspend_both(udev
, PMSG_AUTO_SUSPEND
);
1356 usb_pm_unlock(udev
);
1360 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1361 void usb_autosuspend_work(struct work_struct
*work
)
1363 struct usb_device
*udev
=
1364 container_of(work
, struct usb_device
, autosuspend
.work
);
1366 usb_autopm_do_device(udev
, 0);
1369 /* usb_autoresume_work - callback routine to autoresume a USB device */
1370 void usb_autoresume_work(struct work_struct
*work
)
1372 struct usb_device
*udev
=
1373 container_of(work
, struct usb_device
, autoresume
);
1375 /* Wake it up, let the drivers do their thing, and then put it
1378 if (usb_autopm_do_device(udev
, 1) == 0)
1379 usb_autopm_do_device(udev
, -1);
1383 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1384 * @udev: the usb_device to autosuspend
1386 * This routine should be called when a core subsystem is finished using
1387 * @udev and wants to allow it to autosuspend. Examples would be when
1388 * @udev's device file in usbfs is closed or after a configuration change.
1390 * @udev's usage counter is decremented. If it or any of the usage counters
1391 * for an active interface is greater than 0, no autosuspend request will be
1392 * queued. (If an interface driver does not support autosuspend then its
1393 * usage counter is permanently positive.) Furthermore, if an interface
1394 * driver requires remote-wakeup capability during autosuspend but remote
1395 * wakeup is disabled, the autosuspend will fail.
1397 * Often the caller will hold @udev's device lock, but this is not
1400 * This routine can run only in process context.
1402 void usb_autosuspend_device(struct usb_device
*udev
)
1406 status
= usb_autopm_do_device(udev
, -1);
1407 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1408 __func__
, udev
->pm_usage_cnt
);
1412 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1413 * @udev: the usb_device to autosuspend
1415 * This routine should be called when a core subsystem thinks @udev may
1416 * be ready to autosuspend.
1418 * @udev's usage counter left unchanged. If it or any of the usage counters
1419 * for an active interface is greater than 0, or autosuspend is not allowed
1420 * for any other reason, no autosuspend request will be queued.
1422 * This routine can run only in process context.
1424 void usb_try_autosuspend_device(struct usb_device
*udev
)
1426 usb_autopm_do_device(udev
, 0);
1427 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1428 __func__
, udev
->pm_usage_cnt
);
1432 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1433 * @udev: the usb_device to autoresume
1435 * This routine should be called when a core subsystem wants to use @udev
1436 * and needs to guarantee that it is not suspended. No autosuspend will
1437 * occur until usb_autosuspend_device is called. (Note that this will not
1438 * prevent suspend events originating in the PM core.) Examples would be
1439 * when @udev's device file in usbfs is opened or when a remote-wakeup
1440 * request is received.
1442 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1443 * However if the autoresume fails then the usage counter is re-decremented.
1445 * Often the caller will hold @udev's device lock, but this is not
1446 * necessary (and attempting it might cause deadlock).
1448 * This routine can run only in process context.
1450 int usb_autoresume_device(struct usb_device
*udev
)
1454 status
= usb_autopm_do_device(udev
, 1);
1455 dev_vdbg(&udev
->dev
, "%s: status %d cnt %d\n",
1456 __func__
, status
, udev
->pm_usage_cnt
);
1460 /* Internal routine to adjust an interface's usage counter and change
1461 * its device's autosuspend state.
1463 static int usb_autopm_do_interface(struct usb_interface
*intf
,
1466 struct usb_device
*udev
= interface_to_usbdev(intf
);
1470 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1474 atomic_add(inc_usage_cnt
, &intf
->pm_usage_cnt
);
1475 udev
->last_busy
= jiffies
;
1476 if (inc_usage_cnt
>= 0 &&
1477 atomic_read(&intf
->pm_usage_cnt
) > 0) {
1478 if (udev
->state
== USB_STATE_SUSPENDED
)
1479 status
= usb_resume_both(udev
,
1482 atomic_sub(inc_usage_cnt
, &intf
->pm_usage_cnt
);
1484 udev
->last_busy
= jiffies
;
1485 } else if (inc_usage_cnt
<= 0 &&
1486 atomic_read(&intf
->pm_usage_cnt
) <= 0) {
1487 status
= usb_suspend_both(udev
, PMSG_AUTO_SUSPEND
);
1490 usb_pm_unlock(udev
);
1495 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1496 * @intf: the usb_interface whose counter should be decremented
1498 * This routine should be called by an interface driver when it is
1499 * finished using @intf and wants to allow it to autosuspend. A typical
1500 * example would be a character-device driver when its device file is
1503 * The routine decrements @intf's usage counter. When the counter reaches
1504 * 0, a delayed autosuspend request for @intf's device is queued. When
1505 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1506 * the other usage counters for the sibling interfaces and @intf's
1507 * usb_device, the device and all its interfaces will be autosuspended.
1509 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1510 * core will not change its value other than the increment and decrement
1511 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1512 * may use this simple counter-oriented discipline or may set the value
1515 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1516 * take place only if the device's remote-wakeup facility is enabled.
1518 * Suspend method calls queued by this routine can arrive at any time
1519 * while @intf is resumed and its usage counter is equal to 0. They are
1520 * not protected by the usb_device's lock but only by its pm_mutex.
1521 * Drivers must provide their own synchronization.
1523 * This routine can run only in process context.
1525 void usb_autopm_put_interface(struct usb_interface
*intf
)
1529 status
= usb_autopm_do_interface(intf
, -1);
1530 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1531 __func__
, status
, atomic_read(&intf
->pm_usage_cnt
));
1533 EXPORT_SYMBOL_GPL(usb_autopm_put_interface
);
1536 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1537 * @intf: the usb_interface whose counter should be decremented
1539 * This routine does essentially the same thing as
1540 * usb_autopm_put_interface(): it decrements @intf's usage counter and
1541 * queues a delayed autosuspend request if the counter is <= 0. The
1542 * difference is that it does not acquire the device's pm_mutex;
1543 * callers must handle all synchronization issues themselves.
1545 * Typically a driver would call this routine during an URB's completion
1546 * handler, if no more URBs were pending.
1548 * This routine can run in atomic context.
1550 void usb_autopm_put_interface_async(struct usb_interface
*intf
)
1552 struct usb_device
*udev
= interface_to_usbdev(intf
);
1555 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
1558 udev
->last_busy
= jiffies
;
1559 atomic_dec(&intf
->pm_usage_cnt
);
1560 if (udev
->autosuspend_disabled
|| udev
->autosuspend_delay
< 0)
1562 else if (atomic_read(&intf
->pm_usage_cnt
) <= 0 &&
1563 !timer_pending(&udev
->autosuspend
.timer
)) {
1564 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1565 round_jiffies_up_relative(
1566 udev
->autosuspend_delay
));
1569 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1570 __func__
, status
, atomic_read(&intf
->pm_usage_cnt
));
1572 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async
);
1575 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1576 * @intf: the usb_interface whose counter should be incremented
1578 * This routine should be called by an interface driver when it wants to
1579 * use @intf and needs to guarantee that it is not suspended. In addition,
1580 * the routine prevents @intf from being autosuspended subsequently. (Note
1581 * that this will not prevent suspend events originating in the PM core.)
1582 * This prevention will persist until usb_autopm_put_interface() is called
1583 * or @intf is unbound. A typical example would be a character-device
1584 * driver when its device file is opened.
1587 * The routine increments @intf's usage counter. (However if the
1588 * autoresume fails then the counter is re-decremented.) So long as the
1589 * counter is greater than 0, autosuspend will not be allowed for @intf
1590 * or its usb_device. When the driver is finished using @intf it should
1591 * call usb_autopm_put_interface() to decrement the usage counter and
1592 * queue a delayed autosuspend request (if the counter is <= 0).
1595 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1596 * core will not change its value other than the increment and decrement
1597 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1598 * may use this simple counter-oriented discipline or may set the value
1601 * Resume method calls generated by this routine can arrive at any time
1602 * while @intf is suspended. They are not protected by the usb_device's
1603 * lock but only by its pm_mutex. Drivers must provide their own
1606 * This routine can run only in process context.
1608 int usb_autopm_get_interface(struct usb_interface
*intf
)
1612 status
= usb_autopm_do_interface(intf
, 1);
1613 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1614 __func__
, status
, atomic_read(&intf
->pm_usage_cnt
));
1617 EXPORT_SYMBOL_GPL(usb_autopm_get_interface
);
1620 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1621 * @intf: the usb_interface whose counter should be incremented
1623 * This routine does much the same thing as
1624 * usb_autopm_get_interface(): it increments @intf's usage counter and
1625 * queues an autoresume request if the result is > 0. The differences
1626 * are that it does not acquire the device's pm_mutex (callers must
1627 * handle all synchronization issues themselves), and it does not
1628 * autoresume the device directly (it only queues a request). After a
1629 * successful call, the device will generally not yet be resumed.
1631 * This routine can run in atomic context.
1633 int usb_autopm_get_interface_async(struct usb_interface
*intf
)
1635 struct usb_device
*udev
= interface_to_usbdev(intf
);
1638 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1640 else if (udev
->autoresume_disabled
)
1643 atomic_inc(&intf
->pm_usage_cnt
);
1644 if (atomic_read(&intf
->pm_usage_cnt
) > 0 &&
1645 udev
->state
== USB_STATE_SUSPENDED
)
1646 queue_work(ksuspend_usb_wq
, &udev
->autoresume
);
1648 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1649 __func__
, status
, atomic_read(&intf
->pm_usage_cnt
));
1652 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async
);
1655 * usb_autopm_set_interface - set a USB interface's autosuspend state
1656 * @intf: the usb_interface whose state should be set
1658 * This routine sets the autosuspend state of @intf's device according
1659 * to @intf's usage counter, which the caller must have set previously.
1660 * If the counter is <= 0, the device is autosuspended (if it isn't
1661 * already suspended and if nothing else prevents the autosuspend). If
1662 * the counter is > 0, the device is autoresumed (if it isn't already
1665 int usb_autopm_set_interface(struct usb_interface
*intf
)
1669 status
= usb_autopm_do_interface(intf
, 0);
1670 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1671 __func__
, status
, atomic_read(&intf
->pm_usage_cnt
));
1674 EXPORT_SYMBOL_GPL(usb_autopm_set_interface
);
1678 void usb_autosuspend_work(struct work_struct
*work
)
1681 void usb_autoresume_work(struct work_struct
*work
)
1684 #endif /* CONFIG_USB_SUSPEND */
1687 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1688 * @udev: the usb_device to suspend
1689 * @msg: Power Management message describing this state transition
1691 * This routine handles external suspend requests: ones not generated
1692 * internally by a USB driver (autosuspend) but rather coming from the user
1693 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1694 * out regardless of @udev's usage counter or those of its interfaces,
1695 * and regardless of whether or not remote wakeup is enabled. Of course,
1696 * interface drivers still have the option of failing the suspend (if
1697 * there are unsuspended children, for example).
1699 * The caller must hold @udev's device lock.
1701 int usb_external_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
1705 do_unbind_rebind(udev
, DO_UNBIND
);
1708 status
= usb_suspend_both(udev
, msg
);
1709 usb_pm_unlock(udev
);
1714 * usb_external_resume_device - external resume of a USB device and its interfaces
1715 * @udev: the usb_device to resume
1716 * @msg: Power Management message describing this state transition
1718 * This routine handles external resume requests: ones not generated
1719 * internally by a USB driver (autoresume) but rather coming from the user
1720 * (via sysfs), the PM core (system resume), or the device itself (remote
1721 * wakeup). @udev's usage counter is unaffected.
1723 * The caller must hold @udev's device lock.
1725 int usb_external_resume_device(struct usb_device
*udev
, pm_message_t msg
)
1731 status
= usb_resume_both(udev
, msg
);
1732 udev
->last_busy
= jiffies
;
1733 usb_pm_unlock(udev
);
1735 do_unbind_rebind(udev
, DO_REBIND
);
1737 /* Now that the device is awake, we can start trying to autosuspend
1740 usb_try_autosuspend_device(udev
);
1744 static void choose_wakeup(struct usb_device
*udev
, pm_message_t msg
)
1746 /* Remote wakeup is needed only when we actually go to sleep.
1747 * For things like FREEZE and QUIESCE, if the device is already
1748 * autosuspended then its current wakeup setting is okay.
1750 if (msg
.event
== PM_EVENT_FREEZE
|| msg
.event
== PM_EVENT_QUIESCE
) {
1751 udev
->do_remote_wakeup
= 0;
1755 /* Allow remote wakeup if it is enabled, even if no interface drivers
1758 udev
->do_remote_wakeup
= device_may_wakeup(&udev
->dev
);
1761 int usb_suspend(struct device
*dev
, pm_message_t msg
)
1763 struct usb_device
*udev
;
1765 udev
= to_usb_device(dev
);
1767 /* If udev is already suspended, we can skip this suspend and
1768 * we should also skip the upcoming system resume. High-speed
1769 * root hubs are an exception; they need to resume whenever the
1770 * system wakes up in order for USB-PERSIST port handover to work
1773 if (udev
->state
== USB_STATE_SUSPENDED
) {
1774 if (udev
->parent
|| udev
->speed
!= USB_SPEED_HIGH
)
1775 udev
->skip_sys_resume
= 1;
1779 udev
->skip_sys_resume
= 0;
1780 choose_wakeup(udev
, msg
);
1781 return usb_external_suspend_device(udev
, msg
);
1784 int usb_resume(struct device
*dev
, pm_message_t msg
)
1786 struct usb_device
*udev
;
1789 udev
= to_usb_device(dev
);
1791 /* If udev->skip_sys_resume is set then udev was already suspended
1792 * when the system sleep started, so we don't want to resume it
1793 * during this system wakeup.
1795 if (udev
->skip_sys_resume
)
1797 status
= usb_external_resume_device(udev
, msg
);
1799 /* Avoid PM error messages for devices disconnected while suspended
1800 * as we'll display regular disconnect messages just a bit later.
1802 if (status
== -ENODEV
)
1807 #endif /* CONFIG_PM */
1809 struct bus_type usb_bus_type
= {
1811 .match
= usb_device_match
,
1812 .uevent
= usb_uevent
,