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 * Cancel any pending scheduled resets
190 * [see usb_queue_reset_device()]
192 * Called after unconfiguring / when releasing interfaces. See
193 * comments in __usb_queue_reset_device() regarding
194 * udev->reset_running.
196 static void usb_cancel_queued_reset(struct usb_interface
*iface
)
198 if (iface
->reset_running
== 0)
199 cancel_work_sync(&iface
->reset_ws
);
202 /* called from driver core with dev locked */
203 static int usb_probe_interface(struct device
*dev
)
205 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
206 struct usb_interface
*intf
;
207 struct usb_device
*udev
;
208 const struct usb_device_id
*id
;
211 dev_dbg(dev
, "%s\n", __func__
);
213 if (is_usb_device(dev
)) /* Sanity check */
216 intf
= to_usb_interface(dev
);
217 udev
= interface_to_usbdev(intf
);
218 intf
->needs_binding
= 0;
220 if (udev
->authorized
== 0) {
221 dev_err(&intf
->dev
, "Device is not authorized for usage\n");
225 id
= usb_match_id(intf
, driver
->id_table
);
227 id
= usb_match_dynamic_id(intf
, driver
);
229 dev_dbg(dev
, "%s - got id\n", __func__
);
231 error
= usb_autoresume_device(udev
);
235 /* Interface "power state" doesn't correspond to any hardware
236 * state whatsoever. We use it to record when it's bound to
237 * a driver that may start I/0: it's not frozen/quiesced.
240 intf
->condition
= USB_INTERFACE_BINDING
;
242 /* The interface should always appear to be in use
243 * unless the driver suports autosuspend.
245 intf
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
247 /* Carry out a deferred switch to altsetting 0 */
248 if (intf
->needs_altsetting0
) {
249 usb_set_interface(udev
, intf
->altsetting
[0].
250 desc
.bInterfaceNumber
, 0);
251 intf
->needs_altsetting0
= 0;
254 error
= driver
->probe(intf
, id
);
257 intf
->needs_remote_wakeup
= 0;
258 intf
->condition
= USB_INTERFACE_UNBOUND
;
259 usb_cancel_queued_reset(intf
);
261 intf
->condition
= USB_INTERFACE_BOUND
;
263 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 usb_set_interface(udev
, intf
->altsetting
[0].
305 desc
.bInterfaceNumber
, 0);
307 intf
->needs_altsetting0
= 1;
308 usb_set_intfdata(intf
, NULL
);
310 intf
->condition
= USB_INTERFACE_UNBOUND
;
312 intf
->needs_remote_wakeup
= 0;
315 usb_autosuspend_device(udev
);
321 * usb_driver_claim_interface - bind a driver to an interface
322 * @driver: the driver to be bound
323 * @iface: the interface to which it will be bound; must be in the
324 * usb device's active configuration
325 * @priv: driver data associated with that interface
327 * This is used by usb device drivers that need to claim more than one
328 * interface on a device when probing (audio and acm are current examples).
329 * No device driver should directly modify internal usb_interface or
330 * usb_device structure members.
332 * Few drivers should need to use this routine, since the most natural
333 * way to bind to an interface is to return the private data from
334 * the driver's probe() method.
336 * Callers must own the device lock, so driver probe() entries don't need
337 * extra locking, but other call contexts may need to explicitly claim that
340 int usb_driver_claim_interface(struct usb_driver
*driver
,
341 struct usb_interface
*iface
, void *priv
)
343 struct device
*dev
= &iface
->dev
;
344 struct usb_device
*udev
= interface_to_usbdev(iface
);
350 dev
->driver
= &driver
->drvwrap
.driver
;
351 usb_set_intfdata(iface
, priv
);
352 iface
->needs_binding
= 0;
355 iface
->condition
= USB_INTERFACE_BOUND
;
357 iface
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
360 /* if interface was already added, bind now; else let
361 * the future device_add() bind it, bypassing probe()
363 if (device_is_registered(dev
))
364 retval
= device_bind_driver(dev
);
368 EXPORT_SYMBOL_GPL(usb_driver_claim_interface
);
371 * usb_driver_release_interface - unbind a driver from an interface
372 * @driver: the driver to be unbound
373 * @iface: the interface from which it will be unbound
375 * This can be used by drivers to release an interface without waiting
376 * for their disconnect() methods to be called. In typical cases this
377 * also causes the driver disconnect() method to be called.
379 * This call is synchronous, and may not be used in an interrupt context.
380 * Callers must own the device lock, so driver disconnect() entries don't
381 * need extra locking, but other call contexts may need to explicitly claim
384 void usb_driver_release_interface(struct usb_driver
*driver
,
385 struct usb_interface
*iface
)
387 struct device
*dev
= &iface
->dev
;
389 /* this should never happen, don't release something that's not ours */
390 if (!dev
->driver
|| dev
->driver
!= &driver
->drvwrap
.driver
)
393 /* don't release from within disconnect() */
394 if (iface
->condition
!= USB_INTERFACE_BOUND
)
396 iface
->condition
= USB_INTERFACE_UNBINDING
;
398 /* Release via the driver core only if the interface
399 * has already been registered
401 if (device_is_registered(dev
)) {
402 device_release_driver(dev
);
405 usb_unbind_interface(dev
);
410 EXPORT_SYMBOL_GPL(usb_driver_release_interface
);
412 /* returns 0 if no match, 1 if match */
413 int usb_match_device(struct usb_device
*dev
, const struct usb_device_id
*id
)
415 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
416 id
->idVendor
!= le16_to_cpu(dev
->descriptor
.idVendor
))
419 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_PRODUCT
) &&
420 id
->idProduct
!= le16_to_cpu(dev
->descriptor
.idProduct
))
423 /* No need to test id->bcdDevice_lo != 0, since 0 is never
424 greater than any unsigned number. */
425 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_LO
) &&
426 (id
->bcdDevice_lo
> le16_to_cpu(dev
->descriptor
.bcdDevice
)))
429 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_HI
) &&
430 (id
->bcdDevice_hi
< le16_to_cpu(dev
->descriptor
.bcdDevice
)))
433 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_CLASS
) &&
434 (id
->bDeviceClass
!= dev
->descriptor
.bDeviceClass
))
437 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_SUBCLASS
) &&
438 (id
->bDeviceSubClass
!= dev
->descriptor
.bDeviceSubClass
))
441 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_PROTOCOL
) &&
442 (id
->bDeviceProtocol
!= dev
->descriptor
.bDeviceProtocol
))
448 /* returns 0 if no match, 1 if match */
449 int usb_match_one_id(struct usb_interface
*interface
,
450 const struct usb_device_id
*id
)
452 struct usb_host_interface
*intf
;
453 struct usb_device
*dev
;
455 /* proc_connectinfo in devio.c may call us with id == NULL. */
459 intf
= interface
->cur_altsetting
;
460 dev
= interface_to_usbdev(interface
);
462 if (!usb_match_device(dev
, id
))
465 /* The interface class, subclass, and protocol should never be
466 * checked for a match if the device class is Vendor Specific,
467 * unless the match record specifies the Vendor ID. */
468 if (dev
->descriptor
.bDeviceClass
== USB_CLASS_VENDOR_SPEC
&&
469 !(id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
470 (id
->match_flags
& (USB_DEVICE_ID_MATCH_INT_CLASS
|
471 USB_DEVICE_ID_MATCH_INT_SUBCLASS
|
472 USB_DEVICE_ID_MATCH_INT_PROTOCOL
)))
475 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_CLASS
) &&
476 (id
->bInterfaceClass
!= intf
->desc
.bInterfaceClass
))
479 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_SUBCLASS
) &&
480 (id
->bInterfaceSubClass
!= intf
->desc
.bInterfaceSubClass
))
483 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_PROTOCOL
) &&
484 (id
->bInterfaceProtocol
!= intf
->desc
.bInterfaceProtocol
))
489 EXPORT_SYMBOL_GPL(usb_match_one_id
);
492 * usb_match_id - find first usb_device_id matching device or interface
493 * @interface: the interface of interest
494 * @id: array of usb_device_id structures, terminated by zero entry
496 * usb_match_id searches an array of usb_device_id's and returns
497 * the first one matching the device or interface, or null.
498 * This is used when binding (or rebinding) a driver to an interface.
499 * Most USB device drivers will use this indirectly, through the usb core,
500 * but some layered driver frameworks use it directly.
501 * These device tables are exported with MODULE_DEVICE_TABLE, through
502 * modutils, to support the driver loading functionality of USB hotplugging.
506 * The "match_flags" element in a usb_device_id controls which
507 * members are used. If the corresponding bit is set, the
508 * value in the device_id must match its corresponding member
509 * in the device or interface descriptor, or else the device_id
512 * "driver_info" is normally used only by device drivers,
513 * but you can create a wildcard "matches anything" usb_device_id
514 * as a driver's "modules.usbmap" entry if you provide an id with
515 * only a nonzero "driver_info" field. If you do this, the USB device
516 * driver's probe() routine should use additional intelligence to
517 * decide whether to bind to the specified interface.
519 * What Makes Good usb_device_id Tables:
521 * The match algorithm is very simple, so that intelligence in
522 * driver selection must come from smart driver id records.
523 * Unless you have good reasons to use another selection policy,
524 * provide match elements only in related groups, and order match
525 * specifiers from specific to general. Use the macros provided
526 * for that purpose if you can.
528 * The most specific match specifiers use device descriptor
529 * data. These are commonly used with product-specific matches;
530 * the USB_DEVICE macro lets you provide vendor and product IDs,
531 * and you can also match against ranges of product revisions.
532 * These are widely used for devices with application or vendor
533 * specific bDeviceClass values.
535 * Matches based on device class/subclass/protocol specifications
536 * are slightly more general; use the USB_DEVICE_INFO macro, or
537 * its siblings. These are used with single-function devices
538 * where bDeviceClass doesn't specify that each interface has
541 * Matches based on interface class/subclass/protocol are the
542 * most general; they let drivers bind to any interface on a
543 * multiple-function device. Use the USB_INTERFACE_INFO
544 * macro, or its siblings, to match class-per-interface style
545 * devices (as recorded in bInterfaceClass).
547 * Note that an entry created by USB_INTERFACE_INFO won't match
548 * any interface if the device class is set to Vendor-Specific.
549 * This is deliberate; according to the USB spec the meanings of
550 * the interface class/subclass/protocol for these devices are also
551 * vendor-specific, and hence matching against a standard product
552 * class wouldn't work anyway. If you really want to use an
553 * interface-based match for such a device, create a match record
554 * that also specifies the vendor ID. (Unforunately there isn't a
555 * standard macro for creating records like this.)
557 * Within those groups, remember that not all combinations are
558 * meaningful. For example, don't give a product version range
559 * without vendor and product IDs; or specify a protocol without
560 * its associated class and subclass.
562 const struct usb_device_id
*usb_match_id(struct usb_interface
*interface
,
563 const struct usb_device_id
*id
)
565 /* proc_connectinfo in devio.c may call us with id == NULL. */
569 /* It is important to check that id->driver_info is nonzero,
570 since an entry that is all zeroes except for a nonzero
571 id->driver_info is the way to create an entry that
572 indicates that the driver want to examine every
573 device and interface. */
574 for (; id
->idVendor
|| id
->idProduct
|| id
->bDeviceClass
||
575 id
->bInterfaceClass
|| id
->driver_info
; id
++) {
576 if (usb_match_one_id(interface
, id
))
582 EXPORT_SYMBOL_GPL(usb_match_id
);
584 static int usb_device_match(struct device
*dev
, struct device_driver
*drv
)
586 /* devices and interfaces are handled separately */
587 if (is_usb_device(dev
)) {
589 /* interface drivers never match devices */
590 if (!is_usb_device_driver(drv
))
593 /* TODO: Add real matching code */
597 struct usb_interface
*intf
;
598 struct usb_driver
*usb_drv
;
599 const struct usb_device_id
*id
;
601 /* device drivers never match interfaces */
602 if (is_usb_device_driver(drv
))
605 intf
= to_usb_interface(dev
);
606 usb_drv
= to_usb_driver(drv
);
608 id
= usb_match_id(intf
, usb_drv
->id_table
);
612 id
= usb_match_dynamic_id(intf
, usb_drv
);
620 #ifdef CONFIG_HOTPLUG
621 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
623 struct usb_device
*usb_dev
;
625 /* driver is often null here; dev_dbg() would oops */
626 pr_debug("usb %s: uevent\n", dev_name(dev
));
628 if (is_usb_device(dev
))
629 usb_dev
= to_usb_device(dev
);
631 struct usb_interface
*intf
= to_usb_interface(dev
);
632 usb_dev
= interface_to_usbdev(intf
);
635 if (usb_dev
->devnum
< 0) {
636 pr_debug("usb %s: already deleted?\n", dev_name(dev
));
640 pr_debug("usb %s: bus removed?\n", dev_name(dev
));
644 #ifdef CONFIG_USB_DEVICEFS
645 /* If this is available, userspace programs can directly read
646 * all the device descriptors we don't tell them about. Or
647 * act as usermode drivers.
649 if (add_uevent_var(env
, "DEVICE=/proc/bus/usb/%03d/%03d",
650 usb_dev
->bus
->busnum
, usb_dev
->devnum
))
654 /* per-device configurations are common */
655 if (add_uevent_var(env
, "PRODUCT=%x/%x/%x",
656 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
657 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
658 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
)))
661 /* class-based driver binding models */
662 if (add_uevent_var(env
, "TYPE=%d/%d/%d",
663 usb_dev
->descriptor
.bDeviceClass
,
664 usb_dev
->descriptor
.bDeviceSubClass
,
665 usb_dev
->descriptor
.bDeviceProtocol
))
673 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
677 #endif /* CONFIG_HOTPLUG */
680 * usb_register_device_driver - register a USB device (not interface) driver
681 * @new_udriver: USB operations for the device driver
682 * @owner: module owner of this driver.
684 * Registers a USB device driver with the USB core. The list of
685 * unattached devices will be rescanned whenever a new driver is
686 * added, allowing the new driver to attach to any recognized devices.
687 * Returns a negative error code on failure and 0 on success.
689 int usb_register_device_driver(struct usb_device_driver
*new_udriver
,
690 struct module
*owner
)
697 new_udriver
->drvwrap
.for_devices
= 1;
698 new_udriver
->drvwrap
.driver
.name
= (char *) new_udriver
->name
;
699 new_udriver
->drvwrap
.driver
.bus
= &usb_bus_type
;
700 new_udriver
->drvwrap
.driver
.probe
= usb_probe_device
;
701 new_udriver
->drvwrap
.driver
.remove
= usb_unbind_device
;
702 new_udriver
->drvwrap
.driver
.owner
= owner
;
704 retval
= driver_register(&new_udriver
->drvwrap
.driver
);
707 pr_info("%s: registered new device driver %s\n",
708 usbcore_name
, new_udriver
->name
);
709 usbfs_update_special();
711 printk(KERN_ERR
"%s: error %d registering device "
713 usbcore_name
, retval
, new_udriver
->name
);
718 EXPORT_SYMBOL_GPL(usb_register_device_driver
);
721 * usb_deregister_device_driver - unregister a USB device (not interface) driver
722 * @udriver: USB operations of the device driver to unregister
723 * Context: must be able to sleep
725 * Unlinks the specified driver from the internal USB driver list.
727 void usb_deregister_device_driver(struct usb_device_driver
*udriver
)
729 pr_info("%s: deregistering device driver %s\n",
730 usbcore_name
, udriver
->name
);
732 driver_unregister(&udriver
->drvwrap
.driver
);
733 usbfs_update_special();
735 EXPORT_SYMBOL_GPL(usb_deregister_device_driver
);
738 * usb_register_driver - register a USB interface driver
739 * @new_driver: USB operations for the interface driver
740 * @owner: module owner of this driver.
741 * @mod_name: module name string
743 * Registers a USB interface driver with the USB core. The list of
744 * unattached interfaces will be rescanned whenever a new driver is
745 * added, allowing the new driver to attach to any recognized interfaces.
746 * Returns a negative error code on failure and 0 on success.
748 * NOTE: if you want your driver to use the USB major number, you must call
749 * usb_register_dev() to enable that functionality. This function no longer
750 * takes care of that.
752 int usb_register_driver(struct usb_driver
*new_driver
, struct module
*owner
,
753 const char *mod_name
)
760 new_driver
->drvwrap
.for_devices
= 0;
761 new_driver
->drvwrap
.driver
.name
= (char *) new_driver
->name
;
762 new_driver
->drvwrap
.driver
.bus
= &usb_bus_type
;
763 new_driver
->drvwrap
.driver
.probe
= usb_probe_interface
;
764 new_driver
->drvwrap
.driver
.remove
= usb_unbind_interface
;
765 new_driver
->drvwrap
.driver
.owner
= owner
;
766 new_driver
->drvwrap
.driver
.mod_name
= mod_name
;
767 spin_lock_init(&new_driver
->dynids
.lock
);
768 INIT_LIST_HEAD(&new_driver
->dynids
.list
);
770 retval
= driver_register(&new_driver
->drvwrap
.driver
);
773 pr_info("%s: registered new interface driver %s\n",
774 usbcore_name
, new_driver
->name
);
775 usbfs_update_special();
776 usb_create_newid_file(new_driver
);
778 printk(KERN_ERR
"%s: error %d registering interface "
780 usbcore_name
, retval
, new_driver
->name
);
785 EXPORT_SYMBOL_GPL(usb_register_driver
);
788 * usb_deregister - unregister a USB interface driver
789 * @driver: USB operations of the interface driver to unregister
790 * Context: must be able to sleep
792 * Unlinks the specified driver from the internal USB driver list.
794 * NOTE: If you called usb_register_dev(), you still need to call
795 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
796 * this * call will no longer do it for you.
798 void usb_deregister(struct usb_driver
*driver
)
800 pr_info("%s: deregistering interface driver %s\n",
801 usbcore_name
, driver
->name
);
803 usb_remove_newid_file(driver
);
804 usb_free_dynids(driver
);
805 driver_unregister(&driver
->drvwrap
.driver
);
807 usbfs_update_special();
809 EXPORT_SYMBOL_GPL(usb_deregister
);
811 /* Forced unbinding of a USB interface driver, either because
812 * it doesn't support pre_reset/post_reset/reset_resume or
813 * because it doesn't support suspend/resume.
815 * The caller must hold @intf's device's lock, but not its pm_mutex
816 * and not @intf->dev.sem.
818 void usb_forced_unbind_intf(struct usb_interface
*intf
)
820 struct usb_driver
*driver
= to_usb_driver(intf
->dev
.driver
);
822 dev_dbg(&intf
->dev
, "forced unbind\n");
823 usb_driver_release_interface(driver
, intf
);
825 /* Mark the interface for later rebinding */
826 intf
->needs_binding
= 1;
829 /* Delayed forced unbinding of a USB interface driver and scan
832 * The caller must hold @intf's device's lock, but not its pm_mutex
833 * and not @intf->dev.sem.
835 * Note: Rebinds will be skipped if a system sleep transition is in
836 * progress and the PM "complete" callback hasn't occurred yet.
838 void usb_rebind_intf(struct usb_interface
*intf
)
842 /* Delayed unbind of an existing driver */
843 if (intf
->dev
.driver
) {
844 struct usb_driver
*driver
=
845 to_usb_driver(intf
->dev
.driver
);
847 dev_dbg(&intf
->dev
, "forced unbind\n");
848 usb_driver_release_interface(driver
, intf
);
851 /* Try to rebind the interface */
852 if (intf
->dev
.power
.status
== DPM_ON
) {
853 intf
->needs_binding
= 0;
854 rc
= device_attach(&intf
->dev
);
856 dev_warn(&intf
->dev
, "rebind failed: %d\n", rc
);
865 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
866 * or rebind interfaces that have been unbound, according to @action.
868 * The caller must hold @udev's device lock.
870 static void do_unbind_rebind(struct usb_device
*udev
, int action
)
872 struct usb_host_config
*config
;
874 struct usb_interface
*intf
;
875 struct usb_driver
*drv
;
877 config
= udev
->actconfig
;
879 for (i
= 0; i
< config
->desc
.bNumInterfaces
; ++i
) {
880 intf
= config
->interface
[i
];
883 if (intf
->dev
.driver
) {
884 drv
= to_usb_driver(intf
->dev
.driver
);
885 if (!drv
->suspend
|| !drv
->resume
)
886 usb_forced_unbind_intf(intf
);
890 if (intf
->needs_binding
)
891 usb_rebind_intf(intf
);
898 /* Caller has locked udev's pm_mutex */
899 static int usb_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
901 struct usb_device_driver
*udriver
;
904 if (udev
->state
== USB_STATE_NOTATTACHED
||
905 udev
->state
== USB_STATE_SUSPENDED
)
908 /* For devices that don't have a driver, we do a generic suspend. */
909 if (udev
->dev
.driver
)
910 udriver
= to_usb_device_driver(udev
->dev
.driver
);
912 udev
->do_remote_wakeup
= 0;
913 udriver
= &usb_generic_driver
;
915 status
= udriver
->suspend(udev
, msg
);
918 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
922 /* Caller has locked udev's pm_mutex */
923 static int usb_resume_device(struct usb_device
*udev
, pm_message_t msg
)
925 struct usb_device_driver
*udriver
;
928 if (udev
->state
== USB_STATE_NOTATTACHED
)
931 /* Can't resume it if it doesn't have a driver. */
932 if (udev
->dev
.driver
== NULL
) {
937 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
)
938 udev
->reset_resume
= 1;
940 udriver
= to_usb_device_driver(udev
->dev
.driver
);
941 status
= udriver
->resume(udev
, msg
);
944 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
946 udev
->autoresume_disabled
= 0;
950 /* Caller has locked intf's usb_device's pm mutex */
951 static int usb_suspend_interface(struct usb_device
*udev
,
952 struct usb_interface
*intf
, pm_message_t msg
)
954 struct usb_driver
*driver
;
957 /* with no hardware, USB interfaces only use FREEZE and ON states */
958 if (udev
->state
== USB_STATE_NOTATTACHED
|| !is_active(intf
))
961 /* This can happen; see usb_driver_release_interface() */
962 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
964 driver
= to_usb_driver(intf
->dev
.driver
);
966 if (driver
->suspend
) {
967 status
= driver
->suspend(intf
, msg
);
970 else if (!(msg
.event
& PM_EVENT_AUTO
))
971 dev_err(&intf
->dev
, "%s error %d\n",
974 /* Later we will unbind the driver and reprobe */
975 intf
->needs_binding
= 1;
976 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
977 "suspend", driver
->name
);
982 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
986 /* Caller has locked intf's usb_device's pm_mutex */
987 static int usb_resume_interface(struct usb_device
*udev
,
988 struct usb_interface
*intf
, pm_message_t msg
, int reset_resume
)
990 struct usb_driver
*driver
;
993 if (udev
->state
== USB_STATE_NOTATTACHED
|| is_active(intf
))
996 /* Don't let autoresume interfere with unbinding */
997 if (intf
->condition
== USB_INTERFACE_UNBINDING
)
1000 /* Can't resume it if it doesn't have a driver. */
1001 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
1003 /* Carry out a deferred switch to altsetting 0 */
1004 if (intf
->needs_altsetting0
&&
1005 intf
->dev
.power
.status
== DPM_ON
) {
1006 usb_set_interface(udev
, intf
->altsetting
[0].
1007 desc
.bInterfaceNumber
, 0);
1008 intf
->needs_altsetting0
= 0;
1013 /* Don't resume if the interface is marked for rebinding */
1014 if (intf
->needs_binding
)
1016 driver
= to_usb_driver(intf
->dev
.driver
);
1019 if (driver
->reset_resume
) {
1020 status
= driver
->reset_resume(intf
);
1022 dev_err(&intf
->dev
, "%s error %d\n",
1023 "reset_resume", status
);
1025 intf
->needs_binding
= 1;
1026 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1027 "reset_resume", driver
->name
);
1030 if (driver
->resume
) {
1031 status
= driver
->resume(intf
);
1033 dev_err(&intf
->dev
, "%s error %d\n",
1036 intf
->needs_binding
= 1;
1037 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1038 "resume", driver
->name
);
1043 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
1044 if (status
== 0 && intf
->condition
== USB_INTERFACE_BOUND
)
1047 /* Later we will unbind the driver and/or reprobe, if necessary */
1051 #ifdef CONFIG_USB_SUSPEND
1053 /* Internal routine to check whether we may autosuspend a device. */
1054 static int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1057 struct usb_interface
*intf
;
1058 unsigned long suspend_time
, j
;
1060 /* For autosuspend, fail fast if anything is in use or autosuspend
1061 * is disabled. Also fail if any interfaces require remote wakeup
1062 * but it isn't available.
1064 if (udev
->pm_usage_cnt
> 0)
1066 if (udev
->autosuspend_delay
< 0 || udev
->autosuspend_disabled
)
1069 suspend_time
= udev
->last_busy
+ udev
->autosuspend_delay
;
1070 if (udev
->actconfig
) {
1071 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1072 intf
= udev
->actconfig
->interface
[i
];
1073 if (!is_active(intf
))
1075 if (intf
->pm_usage_cnt
> 0)
1077 if (intf
->needs_remote_wakeup
&&
1078 !udev
->do_remote_wakeup
) {
1079 dev_dbg(&udev
->dev
, "remote wakeup needed "
1080 "for autosuspend\n");
1084 /* Don't allow autosuspend if the device will need
1085 * a reset-resume and any of its interface drivers
1086 * doesn't include support.
1088 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
) {
1089 struct usb_driver
*driver
;
1091 driver
= to_usb_driver(intf
->dev
.driver
);
1092 if (!driver
->reset_resume
||
1093 intf
->needs_remote_wakeup
)
1099 /* If everything is okay but the device hasn't been idle for long
1100 * enough, queue a delayed autosuspend request. If the device
1101 * _has_ been idle for long enough and the reschedule flag is set,
1102 * likewise queue a delayed (1 second) autosuspend request.
1105 if (time_before(j
, suspend_time
))
1108 suspend_time
= j
+ HZ
;
1110 if (!timer_pending(&udev
->autosuspend
.timer
)) {
1111 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1112 round_jiffies_up_relative(suspend_time
- j
));
1121 static inline int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1126 #endif /* CONFIG_USB_SUSPEND */
1129 * usb_suspend_both - suspend a USB device and its interfaces
1130 * @udev: the usb_device to suspend
1131 * @msg: Power Management message describing this state transition
1133 * This is the central routine for suspending USB devices. It calls the
1134 * suspend methods for all the interface drivers in @udev and then calls
1135 * the suspend method for @udev itself. If an error occurs at any stage,
1136 * all the interfaces which were suspended are resumed so that they remain
1137 * in the same state as the device.
1139 * If an autosuspend is in progress the routine checks first to make sure
1140 * that neither the device itself or any of its active interfaces is in use
1141 * (pm_usage_cnt is greater than 0). If they are, the autosuspend fails.
1143 * If the suspend succeeds, the routine recursively queues an autosuspend
1144 * request for @udev's parent device, thereby propagating the change up
1145 * the device tree. If all of the parent's children are now suspended,
1146 * the parent will autosuspend in turn.
1148 * The suspend method calls are subject to mutual exclusion under control
1149 * of @udev's pm_mutex. Many of these calls are also under the protection
1150 * of @udev's device lock (including all requests originating outside the
1151 * USB subsystem), but autosuspend requests generated by a child device or
1152 * interface driver may not be. Usbcore will insure that the method calls
1153 * do not arrive during bind, unbind, or reset operations. However, drivers
1154 * must be prepared to handle suspend calls arriving at unpredictable times.
1155 * The only way to block such calls is to do an autoresume (preventing
1156 * autosuspends) while holding @udev's device lock (preventing outside
1159 * The caller must hold @udev->pm_mutex.
1161 * This routine can run only in process context.
1163 static int usb_suspend_both(struct usb_device
*udev
, pm_message_t msg
)
1167 struct usb_interface
*intf
;
1168 struct usb_device
*parent
= udev
->parent
;
1170 if (udev
->state
== USB_STATE_NOTATTACHED
||
1171 udev
->state
== USB_STATE_SUSPENDED
)
1174 udev
->do_remote_wakeup
= device_may_wakeup(&udev
->dev
);
1176 if (msg
.event
& PM_EVENT_AUTO
) {
1177 status
= autosuspend_check(udev
, 0);
1182 /* Suspend all the interfaces and then udev itself */
1183 if (udev
->actconfig
) {
1184 for (; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1185 intf
= udev
->actconfig
->interface
[i
];
1186 status
= usb_suspend_interface(udev
, intf
, msg
);
1192 status
= usb_suspend_device(udev
, msg
);
1194 /* If the suspend failed, resume interfaces that did get suspended */
1198 msg2
.event
= msg
.event
^ (PM_EVENT_SUSPEND
| PM_EVENT_RESUME
);
1200 intf
= udev
->actconfig
->interface
[i
];
1201 usb_resume_interface(udev
, intf
, msg2
, 0);
1204 /* Try another autosuspend when the interfaces aren't busy */
1205 if (msg
.event
& PM_EVENT_AUTO
)
1206 autosuspend_check(udev
, status
== -EBUSY
);
1208 /* If the suspend succeeded then prevent any more URB submissions,
1209 * flush any outstanding URBs, and propagate the suspend up the tree.
1212 cancel_delayed_work(&udev
->autosuspend
);
1213 udev
->can_submit
= 0;
1214 for (i
= 0; i
< 16; ++i
) {
1215 usb_hcd_flush_endpoint(udev
, udev
->ep_out
[i
]);
1216 usb_hcd_flush_endpoint(udev
, udev
->ep_in
[i
]);
1219 /* If this is just a FREEZE or a PRETHAW, udev might
1220 * not really be suspended. Only true suspends get
1221 * propagated up the device tree.
1223 if (parent
&& udev
->state
== USB_STATE_SUSPENDED
)
1224 usb_autosuspend_device(parent
);
1228 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1233 * usb_resume_both - resume a USB device and its interfaces
1234 * @udev: the usb_device to resume
1235 * @msg: Power Management message describing this state transition
1237 * This is the central routine for resuming USB devices. It calls the
1238 * the resume method for @udev and then calls the resume methods for all
1239 * the interface drivers in @udev.
1241 * Before starting the resume, the routine calls itself recursively for
1242 * the parent device of @udev, thereby propagating the change up the device
1243 * tree and assuring that @udev will be able to resume. If the parent is
1244 * unable to resume successfully, the routine fails.
1246 * The resume method calls are subject to mutual exclusion under control
1247 * of @udev's pm_mutex. Many of these calls are also under the protection
1248 * of @udev's device lock (including all requests originating outside the
1249 * USB subsystem), but autoresume requests generated by a child device or
1250 * interface driver may not be. Usbcore will insure that the method calls
1251 * do not arrive during bind, unbind, or reset operations. However, drivers
1252 * must be prepared to handle resume calls arriving at unpredictable times.
1253 * The only way to block such calls is to do an autoresume (preventing
1254 * other autoresumes) while holding @udev's device lock (preventing outside
1257 * The caller must hold @udev->pm_mutex.
1259 * This routine can run only in process context.
1261 static int usb_resume_both(struct usb_device
*udev
, pm_message_t msg
)
1265 struct usb_interface
*intf
;
1266 struct usb_device
*parent
= udev
->parent
;
1268 cancel_delayed_work(&udev
->autosuspend
);
1269 if (udev
->state
== USB_STATE_NOTATTACHED
) {
1273 udev
->can_submit
= 1;
1275 /* Propagate the resume up the tree, if necessary */
1276 if (udev
->state
== USB_STATE_SUSPENDED
) {
1277 if ((msg
.event
& PM_EVENT_AUTO
) &&
1278 udev
->autoresume_disabled
) {
1283 status
= usb_autoresume_device(parent
);
1285 status
= usb_resume_device(udev
, msg
);
1286 if (status
|| udev
->state
==
1287 USB_STATE_NOTATTACHED
) {
1288 usb_autosuspend_device(parent
);
1290 /* It's possible usb_resume_device()
1291 * failed after the port was
1292 * unsuspended, causing udev to be
1293 * logically disconnected. We don't
1294 * want usb_disconnect() to autosuspend
1295 * the parent again, so tell it that
1296 * udev disconnected while still
1299 USB_STATE_NOTATTACHED
)
1300 udev
->discon_suspended
= 1;
1305 /* We can't progagate beyond the USB subsystem,
1306 * so if a root hub's controller is suspended
1307 * then we're stuck. */
1308 status
= usb_resume_device(udev
, msg
);
1310 } else if (udev
->reset_resume
)
1311 status
= usb_resume_device(udev
, msg
);
1313 if (status
== 0 && udev
->actconfig
) {
1314 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1315 intf
= udev
->actconfig
->interface
[i
];
1316 usb_resume_interface(udev
, intf
, msg
,
1317 udev
->reset_resume
);
1322 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1324 udev
->reset_resume
= 0;
1328 #ifdef CONFIG_USB_SUSPEND
1330 /* Internal routine to adjust a device's usage counter and change
1331 * its autosuspend state.
1333 static int usb_autopm_do_device(struct usb_device
*udev
, int inc_usage_cnt
)
1339 udev
->pm_usage_cnt
+= inc_usage_cnt
;
1340 WARN_ON(udev
->pm_usage_cnt
< 0);
1342 udev
->last_busy
= jiffies
;
1343 if (inc_usage_cnt
>= 0 && udev
->pm_usage_cnt
> 0) {
1344 if (udev
->state
== USB_STATE_SUSPENDED
)
1345 status
= usb_resume_both(udev
, PMSG_AUTO_RESUME
);
1347 udev
->pm_usage_cnt
-= inc_usage_cnt
;
1348 else if (inc_usage_cnt
)
1349 udev
->last_busy
= jiffies
;
1350 } else if (inc_usage_cnt
<= 0 && udev
->pm_usage_cnt
<= 0) {
1351 status
= usb_suspend_both(udev
, PMSG_AUTO_SUSPEND
);
1353 usb_pm_unlock(udev
);
1357 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1358 void usb_autosuspend_work(struct work_struct
*work
)
1360 struct usb_device
*udev
=
1361 container_of(work
, struct usb_device
, autosuspend
.work
);
1363 usb_autopm_do_device(udev
, 0);
1366 /* usb_autoresume_work - callback routine to autoresume a USB device */
1367 void usb_autoresume_work(struct work_struct
*work
)
1369 struct usb_device
*udev
=
1370 container_of(work
, struct usb_device
, autoresume
);
1372 /* Wake it up, let the drivers do their thing, and then put it
1375 if (usb_autopm_do_device(udev
, 1) == 0)
1376 usb_autopm_do_device(udev
, -1);
1380 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1381 * @udev: the usb_device to autosuspend
1383 * This routine should be called when a core subsystem is finished using
1384 * @udev and wants to allow it to autosuspend. Examples would be when
1385 * @udev's device file in usbfs is closed or after a configuration change.
1387 * @udev's usage counter is decremented. If it or any of the usage counters
1388 * for an active interface is greater than 0, no autosuspend request will be
1389 * queued. (If an interface driver does not support autosuspend then its
1390 * usage counter is permanently positive.) Furthermore, if an interface
1391 * driver requires remote-wakeup capability during autosuspend but remote
1392 * wakeup is disabled, the autosuspend will fail.
1394 * Often the caller will hold @udev's device lock, but this is not
1397 * This routine can run only in process context.
1399 void usb_autosuspend_device(struct usb_device
*udev
)
1403 status
= usb_autopm_do_device(udev
, -1);
1404 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1405 __func__
, udev
->pm_usage_cnt
);
1409 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1410 * @udev: the usb_device to autosuspend
1412 * This routine should be called when a core subsystem thinks @udev may
1413 * be ready to autosuspend.
1415 * @udev's usage counter left unchanged. If it or any of the usage counters
1416 * for an active interface is greater than 0, or autosuspend is not allowed
1417 * for any other reason, no autosuspend request will be queued.
1419 * This routine can run only in process context.
1421 void usb_try_autosuspend_device(struct usb_device
*udev
)
1423 usb_autopm_do_device(udev
, 0);
1424 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1425 __func__
, udev
->pm_usage_cnt
);
1429 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1430 * @udev: the usb_device to autoresume
1432 * This routine should be called when a core subsystem wants to use @udev
1433 * and needs to guarantee that it is not suspended. No autosuspend will
1434 * occur until usb_autosuspend_device is called. (Note that this will not
1435 * prevent suspend events originating in the PM core.) Examples would be
1436 * when @udev's device file in usbfs is opened or when a remote-wakeup
1437 * request is received.
1439 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1440 * However if the autoresume fails then the usage counter is re-decremented.
1442 * Often the caller will hold @udev's device lock, but this is not
1443 * necessary (and attempting it might cause deadlock).
1445 * This routine can run only in process context.
1447 int usb_autoresume_device(struct usb_device
*udev
)
1451 status
= usb_autopm_do_device(udev
, 1);
1452 dev_vdbg(&udev
->dev
, "%s: status %d cnt %d\n",
1453 __func__
, status
, udev
->pm_usage_cnt
);
1457 /* Internal routine to adjust an interface's usage counter and change
1458 * its device's autosuspend state.
1460 static int usb_autopm_do_interface(struct usb_interface
*intf
,
1463 struct usb_device
*udev
= interface_to_usbdev(intf
);
1467 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1471 intf
->pm_usage_cnt
+= inc_usage_cnt
;
1472 udev
->last_busy
= jiffies
;
1473 if (inc_usage_cnt
>= 0 && intf
->pm_usage_cnt
> 0) {
1474 if (udev
->state
== USB_STATE_SUSPENDED
)
1475 status
= usb_resume_both(udev
,
1478 intf
->pm_usage_cnt
-= inc_usage_cnt
;
1480 udev
->last_busy
= jiffies
;
1481 } else if (inc_usage_cnt
<= 0 && intf
->pm_usage_cnt
<= 0) {
1482 status
= usb_suspend_both(udev
, PMSG_AUTO_SUSPEND
);
1485 usb_pm_unlock(udev
);
1490 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1491 * @intf: the usb_interface whose counter should be decremented
1493 * This routine should be called by an interface driver when it is
1494 * finished using @intf and wants to allow it to autosuspend. A typical
1495 * example would be a character-device driver when its device file is
1498 * The routine decrements @intf's usage counter. When the counter reaches
1499 * 0, a delayed autosuspend request for @intf's device is queued. When
1500 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1501 * the other usage counters for the sibling interfaces and @intf's
1502 * usb_device, the device and all its interfaces will be autosuspended.
1504 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1505 * core will not change its value other than the increment and decrement
1506 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1507 * may use this simple counter-oriented discipline or may set the value
1510 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1511 * take place only if the device's remote-wakeup facility is enabled.
1513 * Suspend method calls queued by this routine can arrive at any time
1514 * while @intf is resumed and its usage counter is equal to 0. They are
1515 * not protected by the usb_device's lock but only by its pm_mutex.
1516 * Drivers must provide their own synchronization.
1518 * This routine can run only in process context.
1520 void usb_autopm_put_interface(struct usb_interface
*intf
)
1524 status
= usb_autopm_do_interface(intf
, -1);
1525 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1526 __func__
, status
, intf
->pm_usage_cnt
);
1528 EXPORT_SYMBOL_GPL(usb_autopm_put_interface
);
1531 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1532 * @intf: the usb_interface whose counter should be decremented
1534 * This routine does essentially the same thing as
1535 * usb_autopm_put_interface(): it decrements @intf's usage counter and
1536 * queues a delayed autosuspend request if the counter is <= 0. The
1537 * difference is that it does not acquire the device's pm_mutex;
1538 * callers must handle all synchronization issues themselves.
1540 * Typically a driver would call this routine during an URB's completion
1541 * handler, if no more URBs were pending.
1543 * This routine can run in atomic context.
1545 void usb_autopm_put_interface_async(struct usb_interface
*intf
)
1547 struct usb_device
*udev
= interface_to_usbdev(intf
);
1550 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
1553 udev
->last_busy
= jiffies
;
1554 --intf
->pm_usage_cnt
;
1555 if (udev
->autosuspend_disabled
|| udev
->autosuspend_delay
< 0)
1557 else if (intf
->pm_usage_cnt
<= 0 &&
1558 !timer_pending(&udev
->autosuspend
.timer
)) {
1559 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1560 round_jiffies_up_relative(
1561 udev
->autosuspend_delay
));
1564 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1565 __func__
, status
, intf
->pm_usage_cnt
);
1567 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async
);
1570 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1571 * @intf: the usb_interface whose counter should be incremented
1573 * This routine should be called by an interface driver when it wants to
1574 * use @intf and needs to guarantee that it is not suspended. In addition,
1575 * the routine prevents @intf from being autosuspended subsequently. (Note
1576 * that this will not prevent suspend events originating in the PM core.)
1577 * This prevention will persist until usb_autopm_put_interface() is called
1578 * or @intf is unbound. A typical example would be a character-device
1579 * driver when its device file is opened.
1582 * The routine increments @intf's usage counter. (However if the
1583 * autoresume fails then the counter is re-decremented.) So long as the
1584 * counter is greater than 0, autosuspend will not be allowed for @intf
1585 * or its usb_device. When the driver is finished using @intf it should
1586 * call usb_autopm_put_interface() to decrement the usage counter and
1587 * queue a delayed autosuspend request (if the counter is <= 0).
1590 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1591 * core will not change its value other than the increment and decrement
1592 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1593 * may use this simple counter-oriented discipline or may set the value
1596 * Resume method calls generated by this routine can arrive at any time
1597 * while @intf is suspended. They are not protected by the usb_device's
1598 * lock but only by its pm_mutex. Drivers must provide their own
1601 * This routine can run only in process context.
1603 int usb_autopm_get_interface(struct usb_interface
*intf
)
1607 status
= usb_autopm_do_interface(intf
, 1);
1608 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1609 __func__
, status
, intf
->pm_usage_cnt
);
1612 EXPORT_SYMBOL_GPL(usb_autopm_get_interface
);
1615 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1616 * @intf: the usb_interface whose counter should be incremented
1618 * This routine does much the same thing as
1619 * usb_autopm_get_interface(): it increments @intf's usage counter and
1620 * queues an autoresume request if the result is > 0. The differences
1621 * are that it does not acquire the device's pm_mutex (callers must
1622 * handle all synchronization issues themselves), and it does not
1623 * autoresume the device directly (it only queues a request). After a
1624 * successful call, the device will generally not yet be resumed.
1626 * This routine can run in atomic context.
1628 int usb_autopm_get_interface_async(struct usb_interface
*intf
)
1630 struct usb_device
*udev
= interface_to_usbdev(intf
);
1633 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1635 else if (udev
->autoresume_disabled
)
1637 else if (++intf
->pm_usage_cnt
> 0 && udev
->state
== USB_STATE_SUSPENDED
)
1638 queue_work(ksuspend_usb_wq
, &udev
->autoresume
);
1639 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1640 __func__
, status
, intf
->pm_usage_cnt
);
1643 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async
);
1646 * usb_autopm_set_interface - set a USB interface's autosuspend state
1647 * @intf: the usb_interface whose state should be set
1649 * This routine sets the autosuspend state of @intf's device according
1650 * to @intf's usage counter, which the caller must have set previously.
1651 * If the counter is <= 0, the device is autosuspended (if it isn't
1652 * already suspended and if nothing else prevents the autosuspend). If
1653 * the counter is > 0, the device is autoresumed (if it isn't already
1656 int usb_autopm_set_interface(struct usb_interface
*intf
)
1660 status
= usb_autopm_do_interface(intf
, 0);
1661 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1662 __func__
, status
, intf
->pm_usage_cnt
);
1665 EXPORT_SYMBOL_GPL(usb_autopm_set_interface
);
1669 void usb_autosuspend_work(struct work_struct
*work
)
1672 void usb_autoresume_work(struct work_struct
*work
)
1675 #endif /* CONFIG_USB_SUSPEND */
1678 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1679 * @udev: the usb_device to suspend
1680 * @msg: Power Management message describing this state transition
1682 * This routine handles external suspend requests: ones not generated
1683 * internally by a USB driver (autosuspend) but rather coming from the user
1684 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1685 * out regardless of @udev's usage counter or those of its interfaces,
1686 * and regardless of whether or not remote wakeup is enabled. Of course,
1687 * interface drivers still have the option of failing the suspend (if
1688 * there are unsuspended children, for example).
1690 * The caller must hold @udev's device lock.
1692 int usb_external_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
1696 do_unbind_rebind(udev
, DO_UNBIND
);
1699 status
= usb_suspend_both(udev
, msg
);
1700 usb_pm_unlock(udev
);
1705 * usb_external_resume_device - external resume of a USB device and its interfaces
1706 * @udev: the usb_device to resume
1707 * @msg: Power Management message describing this state transition
1709 * This routine handles external resume requests: ones not generated
1710 * internally by a USB driver (autoresume) but rather coming from the user
1711 * (via sysfs), the PM core (system resume), or the device itself (remote
1712 * wakeup). @udev's usage counter is unaffected.
1714 * The caller must hold @udev's device lock.
1716 int usb_external_resume_device(struct usb_device
*udev
, pm_message_t msg
)
1722 status
= usb_resume_both(udev
, msg
);
1723 udev
->last_busy
= jiffies
;
1724 usb_pm_unlock(udev
);
1726 do_unbind_rebind(udev
, DO_REBIND
);
1728 /* Now that the device is awake, we can start trying to autosuspend
1731 usb_try_autosuspend_device(udev
);
1735 int usb_suspend(struct device
*dev
, pm_message_t msg
)
1737 struct usb_device
*udev
;
1739 udev
= to_usb_device(dev
);
1741 /* If udev is already suspended, we can skip this suspend and
1742 * we should also skip the upcoming system resume. High-speed
1743 * root hubs are an exception; they need to resume whenever the
1744 * system wakes up in order for USB-PERSIST port handover to work
1747 if (udev
->state
== USB_STATE_SUSPENDED
) {
1748 if (udev
->parent
|| udev
->speed
!= USB_SPEED_HIGH
)
1749 udev
->skip_sys_resume
= 1;
1753 udev
->skip_sys_resume
= 0;
1754 return usb_external_suspend_device(udev
, msg
);
1757 int usb_resume(struct device
*dev
, pm_message_t msg
)
1759 struct usb_device
*udev
;
1761 udev
= to_usb_device(dev
);
1763 /* If udev->skip_sys_resume is set then udev was already suspended
1764 * when the system sleep started, so we don't want to resume it
1765 * during this system wakeup.
1767 if (udev
->skip_sys_resume
)
1769 return usb_external_resume_device(udev
, msg
);
1772 #endif /* CONFIG_PM */
1774 struct bus_type usb_bus_type
= {
1776 .match
= usb_device_match
,
1777 .uevent
= usb_uevent
,