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
);
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 else if (!error
&& intf
->dev
.power
.status
== DPM_ON
)
301 usb_set_interface(udev
, intf
->altsetting
[0].
302 desc
.bInterfaceNumber
, 0);
304 intf
->needs_altsetting0
= 1;
305 usb_set_intfdata(intf
, NULL
);
307 intf
->condition
= USB_INTERFACE_UNBOUND
;
309 intf
->needs_remote_wakeup
= 0;
312 usb_autosuspend_device(udev
);
318 * usb_driver_claim_interface - bind a driver to an interface
319 * @driver: the driver to be bound
320 * @iface: the interface to which it will be bound; must be in the
321 * usb device's active configuration
322 * @priv: driver data associated with that interface
324 * This is used by usb device drivers that need to claim more than one
325 * interface on a device when probing (audio and acm are current examples).
326 * No device driver should directly modify internal usb_interface or
327 * usb_device structure members.
329 * Few drivers should need to use this routine, since the most natural
330 * way to bind to an interface is to return the private data from
331 * the driver's probe() method.
333 * Callers must own the device lock, so driver probe() entries don't need
334 * extra locking, but other call contexts may need to explicitly claim that
337 int usb_driver_claim_interface(struct usb_driver
*driver
,
338 struct usb_interface
*iface
, void *priv
)
340 struct device
*dev
= &iface
->dev
;
341 struct usb_device
*udev
= interface_to_usbdev(iface
);
347 dev
->driver
= &driver
->drvwrap
.driver
;
348 usb_set_intfdata(iface
, priv
);
349 iface
->needs_binding
= 0;
352 iface
->condition
= USB_INTERFACE_BOUND
;
354 iface
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
357 /* if interface was already added, bind now; else let
358 * the future device_add() bind it, bypassing probe()
360 if (device_is_registered(dev
))
361 retval
= device_bind_driver(dev
);
365 EXPORT_SYMBOL_GPL(usb_driver_claim_interface
);
368 * usb_driver_release_interface - unbind a driver from an interface
369 * @driver: the driver to be unbound
370 * @iface: the interface from which it will be unbound
372 * This can be used by drivers to release an interface without waiting
373 * for their disconnect() methods to be called. In typical cases this
374 * also causes the driver disconnect() method to be called.
376 * This call is synchronous, and may not be used in an interrupt context.
377 * Callers must own the device lock, so driver disconnect() entries don't
378 * need extra locking, but other call contexts may need to explicitly claim
381 void usb_driver_release_interface(struct usb_driver
*driver
,
382 struct usb_interface
*iface
)
384 struct device
*dev
= &iface
->dev
;
385 struct usb_device
*udev
= interface_to_usbdev(iface
);
387 /* this should never happen, don't release something that's not ours */
388 if (!dev
->driver
|| dev
->driver
!= &driver
->drvwrap
.driver
)
391 /* don't release from within disconnect() */
392 if (iface
->condition
!= USB_INTERFACE_BOUND
)
395 /* don't release if the interface hasn't been added yet */
396 if (device_is_registered(dev
)) {
397 iface
->condition
= USB_INTERFACE_UNBINDING
;
398 device_release_driver(dev
);
400 iface
->condition
= USB_INTERFACE_UNBOUND
;
401 usb_cancel_queued_reset(iface
);
404 usb_set_intfdata(iface
, NULL
);
407 iface
->condition
= USB_INTERFACE_UNBOUND
;
408 mark_quiesced(iface
);
409 iface
->needs_remote_wakeup
= 0;
412 EXPORT_SYMBOL_GPL(usb_driver_release_interface
);
414 /* returns 0 if no match, 1 if match */
415 int usb_match_device(struct usb_device
*dev
, const struct usb_device_id
*id
)
417 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
418 id
->idVendor
!= le16_to_cpu(dev
->descriptor
.idVendor
))
421 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_PRODUCT
) &&
422 id
->idProduct
!= le16_to_cpu(dev
->descriptor
.idProduct
))
425 /* No need to test id->bcdDevice_lo != 0, since 0 is never
426 greater than any unsigned number. */
427 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_LO
) &&
428 (id
->bcdDevice_lo
> le16_to_cpu(dev
->descriptor
.bcdDevice
)))
431 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_HI
) &&
432 (id
->bcdDevice_hi
< le16_to_cpu(dev
->descriptor
.bcdDevice
)))
435 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_CLASS
) &&
436 (id
->bDeviceClass
!= dev
->descriptor
.bDeviceClass
))
439 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_SUBCLASS
) &&
440 (id
->bDeviceSubClass
!= dev
->descriptor
.bDeviceSubClass
))
443 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_PROTOCOL
) &&
444 (id
->bDeviceProtocol
!= dev
->descriptor
.bDeviceProtocol
))
450 /* returns 0 if no match, 1 if match */
451 int usb_match_one_id(struct usb_interface
*interface
,
452 const struct usb_device_id
*id
)
454 struct usb_host_interface
*intf
;
455 struct usb_device
*dev
;
457 /* proc_connectinfo in devio.c may call us with id == NULL. */
461 intf
= interface
->cur_altsetting
;
462 dev
= interface_to_usbdev(interface
);
464 if (!usb_match_device(dev
, id
))
467 /* The interface class, subclass, and protocol should never be
468 * checked for a match if the device class is Vendor Specific,
469 * unless the match record specifies the Vendor ID. */
470 if (dev
->descriptor
.bDeviceClass
== USB_CLASS_VENDOR_SPEC
&&
471 !(id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
472 (id
->match_flags
& (USB_DEVICE_ID_MATCH_INT_CLASS
|
473 USB_DEVICE_ID_MATCH_INT_SUBCLASS
|
474 USB_DEVICE_ID_MATCH_INT_PROTOCOL
)))
477 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_CLASS
) &&
478 (id
->bInterfaceClass
!= intf
->desc
.bInterfaceClass
))
481 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_SUBCLASS
) &&
482 (id
->bInterfaceSubClass
!= intf
->desc
.bInterfaceSubClass
))
485 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_PROTOCOL
) &&
486 (id
->bInterfaceProtocol
!= intf
->desc
.bInterfaceProtocol
))
491 EXPORT_SYMBOL_GPL(usb_match_one_id
);
494 * usb_match_id - find first usb_device_id matching device or interface
495 * @interface: the interface of interest
496 * @id: array of usb_device_id structures, terminated by zero entry
498 * usb_match_id searches an array of usb_device_id's and returns
499 * the first one matching the device or interface, or null.
500 * This is used when binding (or rebinding) a driver to an interface.
501 * Most USB device drivers will use this indirectly, through the usb core,
502 * but some layered driver frameworks use it directly.
503 * These device tables are exported with MODULE_DEVICE_TABLE, through
504 * modutils, to support the driver loading functionality of USB hotplugging.
508 * The "match_flags" element in a usb_device_id controls which
509 * members are used. If the corresponding bit is set, the
510 * value in the device_id must match its corresponding member
511 * in the device or interface descriptor, or else the device_id
514 * "driver_info" is normally used only by device drivers,
515 * but you can create a wildcard "matches anything" usb_device_id
516 * as a driver's "modules.usbmap" entry if you provide an id with
517 * only a nonzero "driver_info" field. If you do this, the USB device
518 * driver's probe() routine should use additional intelligence to
519 * decide whether to bind to the specified interface.
521 * What Makes Good usb_device_id Tables:
523 * The match algorithm is very simple, so that intelligence in
524 * driver selection must come from smart driver id records.
525 * Unless you have good reasons to use another selection policy,
526 * provide match elements only in related groups, and order match
527 * specifiers from specific to general. Use the macros provided
528 * for that purpose if you can.
530 * The most specific match specifiers use device descriptor
531 * data. These are commonly used with product-specific matches;
532 * the USB_DEVICE macro lets you provide vendor and product IDs,
533 * and you can also match against ranges of product revisions.
534 * These are widely used for devices with application or vendor
535 * specific bDeviceClass values.
537 * Matches based on device class/subclass/protocol specifications
538 * are slightly more general; use the USB_DEVICE_INFO macro, or
539 * its siblings. These are used with single-function devices
540 * where bDeviceClass doesn't specify that each interface has
543 * Matches based on interface class/subclass/protocol are the
544 * most general; they let drivers bind to any interface on a
545 * multiple-function device. Use the USB_INTERFACE_INFO
546 * macro, or its siblings, to match class-per-interface style
547 * devices (as recorded in bInterfaceClass).
549 * Note that an entry created by USB_INTERFACE_INFO won't match
550 * any interface if the device class is set to Vendor-Specific.
551 * This is deliberate; according to the USB spec the meanings of
552 * the interface class/subclass/protocol for these devices are also
553 * vendor-specific, and hence matching against a standard product
554 * class wouldn't work anyway. If you really want to use an
555 * interface-based match for such a device, create a match record
556 * that also specifies the vendor ID. (Unforunately there isn't a
557 * standard macro for creating records like this.)
559 * Within those groups, remember that not all combinations are
560 * meaningful. For example, don't give a product version range
561 * without vendor and product IDs; or specify a protocol without
562 * its associated class and subclass.
564 const struct usb_device_id
*usb_match_id(struct usb_interface
*interface
,
565 const struct usb_device_id
*id
)
567 /* proc_connectinfo in devio.c may call us with id == NULL. */
571 /* It is important to check that id->driver_info is nonzero,
572 since an entry that is all zeroes except for a nonzero
573 id->driver_info is the way to create an entry that
574 indicates that the driver want to examine every
575 device and interface. */
576 for (; id
->idVendor
|| id
->idProduct
|| id
->bDeviceClass
||
577 id
->bInterfaceClass
|| id
->driver_info
; id
++) {
578 if (usb_match_one_id(interface
, id
))
584 EXPORT_SYMBOL_GPL(usb_match_id
);
586 static int usb_device_match(struct device
*dev
, struct device_driver
*drv
)
588 /* devices and interfaces are handled separately */
589 if (is_usb_device(dev
)) {
591 /* interface drivers never match devices */
592 if (!is_usb_device_driver(drv
))
595 /* TODO: Add real matching code */
599 struct usb_interface
*intf
;
600 struct usb_driver
*usb_drv
;
601 const struct usb_device_id
*id
;
603 /* device drivers never match interfaces */
604 if (is_usb_device_driver(drv
))
607 intf
= to_usb_interface(dev
);
608 usb_drv
= to_usb_driver(drv
);
610 id
= usb_match_id(intf
, usb_drv
->id_table
);
614 id
= usb_match_dynamic_id(intf
, usb_drv
);
622 #ifdef CONFIG_HOTPLUG
623 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
625 struct usb_device
*usb_dev
;
627 /* driver is often null here; dev_dbg() would oops */
628 pr_debug("usb %s: uevent\n", dev_name(dev
));
630 if (is_usb_device(dev
))
631 usb_dev
= to_usb_device(dev
);
633 struct usb_interface
*intf
= to_usb_interface(dev
);
634 usb_dev
= interface_to_usbdev(intf
);
637 if (usb_dev
->devnum
< 0) {
638 pr_debug("usb %s: already deleted?\n", dev_name(dev
));
642 pr_debug("usb %s: bus removed?\n", dev_name(dev
));
646 #ifdef CONFIG_USB_DEVICEFS
647 /* If this is available, userspace programs can directly read
648 * all the device descriptors we don't tell them about. Or
649 * act as usermode drivers.
651 if (add_uevent_var(env
, "DEVICE=/proc/bus/usb/%03d/%03d",
652 usb_dev
->bus
->busnum
, usb_dev
->devnum
))
656 /* per-device configurations are common */
657 if (add_uevent_var(env
, "PRODUCT=%x/%x/%x",
658 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
659 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
660 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
)))
663 /* class-based driver binding models */
664 if (add_uevent_var(env
, "TYPE=%d/%d/%d",
665 usb_dev
->descriptor
.bDeviceClass
,
666 usb_dev
->descriptor
.bDeviceSubClass
,
667 usb_dev
->descriptor
.bDeviceProtocol
))
675 static int usb_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
679 #endif /* CONFIG_HOTPLUG */
682 * usb_register_device_driver - register a USB device (not interface) driver
683 * @new_udriver: USB operations for the device driver
684 * @owner: module owner of this driver.
686 * Registers a USB device driver with the USB core. The list of
687 * unattached devices will be rescanned whenever a new driver is
688 * added, allowing the new driver to attach to any recognized devices.
689 * Returns a negative error code on failure and 0 on success.
691 int usb_register_device_driver(struct usb_device_driver
*new_udriver
,
692 struct module
*owner
)
699 new_udriver
->drvwrap
.for_devices
= 1;
700 new_udriver
->drvwrap
.driver
.name
= (char *) new_udriver
->name
;
701 new_udriver
->drvwrap
.driver
.bus
= &usb_bus_type
;
702 new_udriver
->drvwrap
.driver
.probe
= usb_probe_device
;
703 new_udriver
->drvwrap
.driver
.remove
= usb_unbind_device
;
704 new_udriver
->drvwrap
.driver
.owner
= owner
;
706 retval
= driver_register(&new_udriver
->drvwrap
.driver
);
709 pr_info("%s: registered new device driver %s\n",
710 usbcore_name
, new_udriver
->name
);
711 usbfs_update_special();
713 printk(KERN_ERR
"%s: error %d registering device "
715 usbcore_name
, retval
, new_udriver
->name
);
720 EXPORT_SYMBOL_GPL(usb_register_device_driver
);
723 * usb_deregister_device_driver - unregister a USB device (not interface) driver
724 * @udriver: USB operations of the device driver to unregister
725 * Context: must be able to sleep
727 * Unlinks the specified driver from the internal USB driver list.
729 void usb_deregister_device_driver(struct usb_device_driver
*udriver
)
731 pr_info("%s: deregistering device driver %s\n",
732 usbcore_name
, udriver
->name
);
734 driver_unregister(&udriver
->drvwrap
.driver
);
735 usbfs_update_special();
737 EXPORT_SYMBOL_GPL(usb_deregister_device_driver
);
740 * usb_register_driver - register a USB interface driver
741 * @new_driver: USB operations for the interface driver
742 * @owner: module owner of this driver.
743 * @mod_name: module name string
745 * Registers a USB interface driver with the USB core. The list of
746 * unattached interfaces will be rescanned whenever a new driver is
747 * added, allowing the new driver to attach to any recognized interfaces.
748 * Returns a negative error code on failure and 0 on success.
750 * NOTE: if you want your driver to use the USB major number, you must call
751 * usb_register_dev() to enable that functionality. This function no longer
752 * takes care of that.
754 int usb_register_driver(struct usb_driver
*new_driver
, struct module
*owner
,
755 const char *mod_name
)
762 new_driver
->drvwrap
.for_devices
= 0;
763 new_driver
->drvwrap
.driver
.name
= (char *) new_driver
->name
;
764 new_driver
->drvwrap
.driver
.bus
= &usb_bus_type
;
765 new_driver
->drvwrap
.driver
.probe
= usb_probe_interface
;
766 new_driver
->drvwrap
.driver
.remove
= usb_unbind_interface
;
767 new_driver
->drvwrap
.driver
.owner
= owner
;
768 new_driver
->drvwrap
.driver
.mod_name
= mod_name
;
769 spin_lock_init(&new_driver
->dynids
.lock
);
770 INIT_LIST_HEAD(&new_driver
->dynids
.list
);
772 retval
= driver_register(&new_driver
->drvwrap
.driver
);
775 pr_info("%s: registered new interface driver %s\n",
776 usbcore_name
, new_driver
->name
);
777 usbfs_update_special();
778 usb_create_newid_file(new_driver
);
780 printk(KERN_ERR
"%s: error %d registering interface "
782 usbcore_name
, retval
, new_driver
->name
);
787 EXPORT_SYMBOL_GPL(usb_register_driver
);
790 * usb_deregister - unregister a USB interface driver
791 * @driver: USB operations of the interface driver to unregister
792 * Context: must be able to sleep
794 * Unlinks the specified driver from the internal USB driver list.
796 * NOTE: If you called usb_register_dev(), you still need to call
797 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
798 * this * call will no longer do it for you.
800 void usb_deregister(struct usb_driver
*driver
)
802 pr_info("%s: deregistering interface driver %s\n",
803 usbcore_name
, driver
->name
);
805 usb_remove_newid_file(driver
);
806 usb_free_dynids(driver
);
807 driver_unregister(&driver
->drvwrap
.driver
);
809 usbfs_update_special();
811 EXPORT_SYMBOL_GPL(usb_deregister
);
813 /* Forced unbinding of a USB interface driver, either because
814 * it doesn't support pre_reset/post_reset/reset_resume or
815 * because it doesn't support suspend/resume.
817 * The caller must hold @intf's device's lock, but not its pm_mutex
818 * and not @intf->dev.sem.
820 void usb_forced_unbind_intf(struct usb_interface
*intf
)
822 struct usb_driver
*driver
= to_usb_driver(intf
->dev
.driver
);
824 dev_dbg(&intf
->dev
, "forced unbind\n");
825 usb_driver_release_interface(driver
, intf
);
827 /* Mark the interface for later rebinding */
828 intf
->needs_binding
= 1;
831 /* Delayed forced unbinding of a USB interface driver and scan
834 * The caller must hold @intf's device's lock, but not its pm_mutex
835 * and not @intf->dev.sem.
837 * Note: Rebinds will be skipped if a system sleep transition is in
838 * progress and the PM "complete" callback hasn't occurred yet.
840 void usb_rebind_intf(struct usb_interface
*intf
)
844 /* Delayed unbind of an existing driver */
845 if (intf
->dev
.driver
) {
846 struct usb_driver
*driver
=
847 to_usb_driver(intf
->dev
.driver
);
849 dev_dbg(&intf
->dev
, "forced unbind\n");
850 usb_driver_release_interface(driver
, intf
);
853 /* Try to rebind the interface */
854 if (intf
->dev
.power
.status
== DPM_ON
) {
855 intf
->needs_binding
= 0;
856 rc
= device_attach(&intf
->dev
);
858 dev_warn(&intf
->dev
, "rebind failed: %d\n", rc
);
867 /* Unbind drivers for @udev's interfaces that don't support suspend/resume,
868 * or rebind interfaces that have been unbound, according to @action.
870 * The caller must hold @udev's device lock.
872 static void do_unbind_rebind(struct usb_device
*udev
, int action
)
874 struct usb_host_config
*config
;
876 struct usb_interface
*intf
;
877 struct usb_driver
*drv
;
879 config
= udev
->actconfig
;
881 for (i
= 0; i
< config
->desc
.bNumInterfaces
; ++i
) {
882 intf
= config
->interface
[i
];
885 if (intf
->dev
.driver
) {
886 drv
= to_usb_driver(intf
->dev
.driver
);
887 if (!drv
->suspend
|| !drv
->resume
)
888 usb_forced_unbind_intf(intf
);
892 if (intf
->needs_binding
)
893 usb_rebind_intf(intf
);
900 /* Caller has locked udev's pm_mutex */
901 static int usb_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
903 struct usb_device_driver
*udriver
;
906 if (udev
->state
== USB_STATE_NOTATTACHED
||
907 udev
->state
== USB_STATE_SUSPENDED
)
910 /* For devices that don't have a driver, we do a generic suspend. */
911 if (udev
->dev
.driver
)
912 udriver
= to_usb_device_driver(udev
->dev
.driver
);
914 udev
->do_remote_wakeup
= 0;
915 udriver
= &usb_generic_driver
;
917 status
= udriver
->suspend(udev
, msg
);
920 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
924 /* Caller has locked udev's pm_mutex */
925 static int usb_resume_device(struct usb_device
*udev
, pm_message_t msg
)
927 struct usb_device_driver
*udriver
;
930 if (udev
->state
== USB_STATE_NOTATTACHED
)
933 /* Can't resume it if it doesn't have a driver. */
934 if (udev
->dev
.driver
== NULL
) {
939 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
)
940 udev
->reset_resume
= 1;
942 udriver
= to_usb_device_driver(udev
->dev
.driver
);
943 status
= udriver
->resume(udev
, msg
);
946 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
948 udev
->autoresume_disabled
= 0;
952 /* Caller has locked intf's usb_device's pm mutex */
953 static int usb_suspend_interface(struct usb_device
*udev
,
954 struct usb_interface
*intf
, pm_message_t msg
)
956 struct usb_driver
*driver
;
959 /* with no hardware, USB interfaces only use FREEZE and ON states */
960 if (udev
->state
== USB_STATE_NOTATTACHED
|| !is_active(intf
))
963 /* This can happen; see usb_driver_release_interface() */
964 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
966 driver
= to_usb_driver(intf
->dev
.driver
);
968 if (driver
->suspend
) {
969 status
= driver
->suspend(intf
, msg
);
972 else if (!(msg
.event
& PM_EVENT_AUTO
))
973 dev_err(&intf
->dev
, "%s error %d\n",
976 /* Later we will unbind the driver and reprobe */
977 intf
->needs_binding
= 1;
978 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
979 "suspend", driver
->name
);
984 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
988 /* Caller has locked intf's usb_device's pm_mutex */
989 static int usb_resume_interface(struct usb_device
*udev
,
990 struct usb_interface
*intf
, pm_message_t msg
, int reset_resume
)
992 struct usb_driver
*driver
;
995 if (udev
->state
== USB_STATE_NOTATTACHED
|| is_active(intf
))
998 /* Don't let autoresume interfere with unbinding */
999 if (intf
->condition
== USB_INTERFACE_UNBINDING
)
1002 /* Can't resume it if it doesn't have a driver. */
1003 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
1005 /* Carry out a deferred switch to altsetting 0 */
1006 if (intf
->needs_altsetting0
&&
1007 intf
->dev
.power
.status
== DPM_ON
) {
1008 usb_set_interface(udev
, intf
->altsetting
[0].
1009 desc
.bInterfaceNumber
, 0);
1010 intf
->needs_altsetting0
= 0;
1015 /* Don't resume if the interface is marked for rebinding */
1016 if (intf
->needs_binding
)
1018 driver
= to_usb_driver(intf
->dev
.driver
);
1021 if (driver
->reset_resume
) {
1022 status
= driver
->reset_resume(intf
);
1024 dev_err(&intf
->dev
, "%s error %d\n",
1025 "reset_resume", status
);
1027 intf
->needs_binding
= 1;
1028 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1029 "reset_resume", driver
->name
);
1032 if (driver
->resume
) {
1033 status
= driver
->resume(intf
);
1035 dev_err(&intf
->dev
, "%s error %d\n",
1038 intf
->needs_binding
= 1;
1039 dev_warn(&intf
->dev
, "no %s for driver %s?\n",
1040 "resume", driver
->name
);
1045 dev_vdbg(&intf
->dev
, "%s: status %d\n", __func__
, status
);
1046 if (status
== 0 && intf
->condition
== USB_INTERFACE_BOUND
)
1049 /* Later we will unbind the driver and/or reprobe, if necessary */
1053 #ifdef CONFIG_USB_SUSPEND
1055 /* Internal routine to check whether we may autosuspend a device. */
1056 static int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1059 struct usb_interface
*intf
;
1060 unsigned long suspend_time
, j
;
1062 /* For autosuspend, fail fast if anything is in use or autosuspend
1063 * is disabled. Also fail if any interfaces require remote wakeup
1064 * but it isn't available.
1066 if (udev
->pm_usage_cnt
> 0)
1068 if (udev
->autosuspend_delay
< 0 || udev
->autosuspend_disabled
)
1071 suspend_time
= udev
->last_busy
+ udev
->autosuspend_delay
;
1072 if (udev
->actconfig
) {
1073 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1074 intf
= udev
->actconfig
->interface
[i
];
1075 if (!is_active(intf
))
1077 if (intf
->pm_usage_cnt
> 0)
1079 if (intf
->needs_remote_wakeup
&&
1080 !udev
->do_remote_wakeup
) {
1081 dev_dbg(&udev
->dev
, "remote wakeup needed "
1082 "for autosuspend\n");
1086 /* Don't allow autosuspend if the device will need
1087 * a reset-resume and any of its interface drivers
1088 * doesn't include support.
1090 if (udev
->quirks
& USB_QUIRK_RESET_RESUME
) {
1091 struct usb_driver
*driver
;
1093 driver
= to_usb_driver(intf
->dev
.driver
);
1094 if (!driver
->reset_resume
||
1095 intf
->needs_remote_wakeup
)
1101 /* If everything is okay but the device hasn't been idle for long
1102 * enough, queue a delayed autosuspend request. If the device
1103 * _has_ been idle for long enough and the reschedule flag is set,
1104 * likewise queue a delayed (1 second) autosuspend request.
1107 if (time_before(j
, suspend_time
))
1110 suspend_time
= j
+ HZ
;
1112 if (!timer_pending(&udev
->autosuspend
.timer
)) {
1113 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1114 round_jiffies_up_relative(suspend_time
- j
));
1123 static inline int autosuspend_check(struct usb_device
*udev
, int reschedule
)
1128 #endif /* CONFIG_USB_SUSPEND */
1131 * usb_suspend_both - suspend a USB device and its interfaces
1132 * @udev: the usb_device to suspend
1133 * @msg: Power Management message describing this state transition
1135 * This is the central routine for suspending USB devices. It calls the
1136 * suspend methods for all the interface drivers in @udev and then calls
1137 * the suspend method for @udev itself. If an error occurs at any stage,
1138 * all the interfaces which were suspended are resumed so that they remain
1139 * in the same state as the device.
1141 * If an autosuspend is in progress the routine checks first to make sure
1142 * that neither the device itself or any of its active interfaces is in use
1143 * (pm_usage_cnt is greater than 0). If they are, the autosuspend fails.
1145 * If the suspend succeeds, the routine recursively queues an autosuspend
1146 * request for @udev's parent device, thereby propagating the change up
1147 * the device tree. If all of the parent's children are now suspended,
1148 * the parent will autosuspend in turn.
1150 * The suspend method calls are subject to mutual exclusion under control
1151 * of @udev's pm_mutex. Many of these calls are also under the protection
1152 * of @udev's device lock (including all requests originating outside the
1153 * USB subsystem), but autosuspend requests generated by a child device or
1154 * interface driver may not be. Usbcore will insure that the method calls
1155 * do not arrive during bind, unbind, or reset operations. However, drivers
1156 * must be prepared to handle suspend calls arriving at unpredictable times.
1157 * The only way to block such calls is to do an autoresume (preventing
1158 * autosuspends) while holding @udev's device lock (preventing outside
1161 * The caller must hold @udev->pm_mutex.
1163 * This routine can run only in process context.
1165 static int usb_suspend_both(struct usb_device
*udev
, pm_message_t msg
)
1169 struct usb_interface
*intf
;
1170 struct usb_device
*parent
= udev
->parent
;
1172 if (udev
->state
== USB_STATE_NOTATTACHED
||
1173 udev
->state
== USB_STATE_SUSPENDED
)
1176 udev
->do_remote_wakeup
= device_may_wakeup(&udev
->dev
);
1178 if (msg
.event
& PM_EVENT_AUTO
) {
1179 status
= autosuspend_check(udev
, 0);
1184 /* Suspend all the interfaces and then udev itself */
1185 if (udev
->actconfig
) {
1186 for (; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1187 intf
= udev
->actconfig
->interface
[i
];
1188 status
= usb_suspend_interface(udev
, intf
, msg
);
1194 status
= usb_suspend_device(udev
, msg
);
1196 /* If the suspend failed, resume interfaces that did get suspended */
1200 msg2
.event
= msg
.event
^ (PM_EVENT_SUSPEND
| PM_EVENT_RESUME
);
1202 intf
= udev
->actconfig
->interface
[i
];
1203 usb_resume_interface(udev
, intf
, msg2
, 0);
1206 /* Try another autosuspend when the interfaces aren't busy */
1207 if (msg
.event
& PM_EVENT_AUTO
)
1208 autosuspend_check(udev
, status
== -EBUSY
);
1210 /* If the suspend succeeded then prevent any more URB submissions,
1211 * flush any outstanding URBs, and propagate the suspend up the tree.
1214 cancel_delayed_work(&udev
->autosuspend
);
1215 udev
->can_submit
= 0;
1216 for (i
= 0; i
< 16; ++i
) {
1217 usb_hcd_flush_endpoint(udev
, udev
->ep_out
[i
]);
1218 usb_hcd_flush_endpoint(udev
, udev
->ep_in
[i
]);
1221 /* If this is just a FREEZE or a PRETHAW, udev might
1222 * not really be suspended. Only true suspends get
1223 * propagated up the device tree.
1225 if (parent
&& udev
->state
== USB_STATE_SUSPENDED
)
1226 usb_autosuspend_device(parent
);
1230 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1235 * usb_resume_both - resume a USB device and its interfaces
1236 * @udev: the usb_device to resume
1237 * @msg: Power Management message describing this state transition
1239 * This is the central routine for resuming USB devices. It calls the
1240 * the resume method for @udev and then calls the resume methods for all
1241 * the interface drivers in @udev.
1243 * Before starting the resume, the routine calls itself recursively for
1244 * the parent device of @udev, thereby propagating the change up the device
1245 * tree and assuring that @udev will be able to resume. If the parent is
1246 * unable to resume successfully, the routine fails.
1248 * The resume method calls are subject to mutual exclusion under control
1249 * of @udev's pm_mutex. Many of these calls are also under the protection
1250 * of @udev's device lock (including all requests originating outside the
1251 * USB subsystem), but autoresume requests generated by a child device or
1252 * interface driver may not be. Usbcore will insure that the method calls
1253 * do not arrive during bind, unbind, or reset operations. However, drivers
1254 * must be prepared to handle resume calls arriving at unpredictable times.
1255 * The only way to block such calls is to do an autoresume (preventing
1256 * other autoresumes) while holding @udev's device lock (preventing outside
1259 * The caller must hold @udev->pm_mutex.
1261 * This routine can run only in process context.
1263 static int usb_resume_both(struct usb_device
*udev
, pm_message_t msg
)
1267 struct usb_interface
*intf
;
1268 struct usb_device
*parent
= udev
->parent
;
1270 cancel_delayed_work(&udev
->autosuspend
);
1271 if (udev
->state
== USB_STATE_NOTATTACHED
) {
1275 udev
->can_submit
= 1;
1277 /* Propagate the resume up the tree, if necessary */
1278 if (udev
->state
== USB_STATE_SUSPENDED
) {
1279 if ((msg
.event
& PM_EVENT_AUTO
) &&
1280 udev
->autoresume_disabled
) {
1285 status
= usb_autoresume_device(parent
);
1287 status
= usb_resume_device(udev
, msg
);
1288 if (status
|| udev
->state
==
1289 USB_STATE_NOTATTACHED
) {
1290 usb_autosuspend_device(parent
);
1292 /* It's possible usb_resume_device()
1293 * failed after the port was
1294 * unsuspended, causing udev to be
1295 * logically disconnected. We don't
1296 * want usb_disconnect() to autosuspend
1297 * the parent again, so tell it that
1298 * udev disconnected while still
1301 USB_STATE_NOTATTACHED
)
1302 udev
->discon_suspended
= 1;
1307 /* We can't progagate beyond the USB subsystem,
1308 * so if a root hub's controller is suspended
1309 * then we're stuck. */
1310 status
= usb_resume_device(udev
, msg
);
1312 } else if (udev
->reset_resume
)
1313 status
= usb_resume_device(udev
, msg
);
1315 if (status
== 0 && udev
->actconfig
) {
1316 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1317 intf
= udev
->actconfig
->interface
[i
];
1318 usb_resume_interface(udev
, intf
, msg
,
1319 udev
->reset_resume
);
1324 dev_vdbg(&udev
->dev
, "%s: status %d\n", __func__
, status
);
1326 udev
->reset_resume
= 0;
1330 #ifdef CONFIG_USB_SUSPEND
1332 /* Internal routine to adjust a device's usage counter and change
1333 * its autosuspend state.
1335 static int usb_autopm_do_device(struct usb_device
*udev
, int inc_usage_cnt
)
1341 udev
->pm_usage_cnt
+= inc_usage_cnt
;
1342 WARN_ON(udev
->pm_usage_cnt
< 0);
1344 udev
->last_busy
= jiffies
;
1345 if (inc_usage_cnt
>= 0 && udev
->pm_usage_cnt
> 0) {
1346 if (udev
->state
== USB_STATE_SUSPENDED
)
1347 status
= usb_resume_both(udev
, PMSG_AUTO_RESUME
);
1349 udev
->pm_usage_cnt
-= inc_usage_cnt
;
1350 else if (inc_usage_cnt
)
1351 udev
->last_busy
= jiffies
;
1352 } else if (inc_usage_cnt
<= 0 && udev
->pm_usage_cnt
<= 0) {
1353 status
= usb_suspend_both(udev
, PMSG_AUTO_SUSPEND
);
1355 usb_pm_unlock(udev
);
1359 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1360 void usb_autosuspend_work(struct work_struct
*work
)
1362 struct usb_device
*udev
=
1363 container_of(work
, struct usb_device
, autosuspend
.work
);
1365 usb_autopm_do_device(udev
, 0);
1368 /* usb_autoresume_work - callback routine to autoresume a USB device */
1369 void usb_autoresume_work(struct work_struct
*work
)
1371 struct usb_device
*udev
=
1372 container_of(work
, struct usb_device
, autoresume
);
1374 /* Wake it up, let the drivers do their thing, and then put it
1377 if (usb_autopm_do_device(udev
, 1) == 0)
1378 usb_autopm_do_device(udev
, -1);
1382 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1383 * @udev: the usb_device to autosuspend
1385 * This routine should be called when a core subsystem is finished using
1386 * @udev and wants to allow it to autosuspend. Examples would be when
1387 * @udev's device file in usbfs is closed or after a configuration change.
1389 * @udev's usage counter is decremented. If it or any of the usage counters
1390 * for an active interface is greater than 0, no autosuspend request will be
1391 * queued. (If an interface driver does not support autosuspend then its
1392 * usage counter is permanently positive.) Furthermore, if an interface
1393 * driver requires remote-wakeup capability during autosuspend but remote
1394 * wakeup is disabled, the autosuspend will fail.
1396 * Often the caller will hold @udev's device lock, but this is not
1399 * This routine can run only in process context.
1401 void usb_autosuspend_device(struct usb_device
*udev
)
1405 status
= usb_autopm_do_device(udev
, -1);
1406 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1407 __func__
, udev
->pm_usage_cnt
);
1411 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1412 * @udev: the usb_device to autosuspend
1414 * This routine should be called when a core subsystem thinks @udev may
1415 * be ready to autosuspend.
1417 * @udev's usage counter left unchanged. If it or any of the usage counters
1418 * for an active interface is greater than 0, or autosuspend is not allowed
1419 * for any other reason, no autosuspend request will be queued.
1421 * This routine can run only in process context.
1423 void usb_try_autosuspend_device(struct usb_device
*udev
)
1425 usb_autopm_do_device(udev
, 0);
1426 dev_vdbg(&udev
->dev
, "%s: cnt %d\n",
1427 __func__
, udev
->pm_usage_cnt
);
1431 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1432 * @udev: the usb_device to autoresume
1434 * This routine should be called when a core subsystem wants to use @udev
1435 * and needs to guarantee that it is not suspended. No autosuspend will
1436 * occur until usb_autosuspend_device is called. (Note that this will not
1437 * prevent suspend events originating in the PM core.) Examples would be
1438 * when @udev's device file in usbfs is opened or when a remote-wakeup
1439 * request is received.
1441 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1442 * However if the autoresume fails then the usage counter is re-decremented.
1444 * Often the caller will hold @udev's device lock, but this is not
1445 * necessary (and attempting it might cause deadlock).
1447 * This routine can run only in process context.
1449 int usb_autoresume_device(struct usb_device
*udev
)
1453 status
= usb_autopm_do_device(udev
, 1);
1454 dev_vdbg(&udev
->dev
, "%s: status %d cnt %d\n",
1455 __func__
, status
, udev
->pm_usage_cnt
);
1459 /* Internal routine to adjust an interface's usage counter and change
1460 * its device's autosuspend state.
1462 static int usb_autopm_do_interface(struct usb_interface
*intf
,
1465 struct usb_device
*udev
= interface_to_usbdev(intf
);
1469 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1473 intf
->pm_usage_cnt
+= inc_usage_cnt
;
1474 udev
->last_busy
= jiffies
;
1475 if (inc_usage_cnt
>= 0 && intf
->pm_usage_cnt
> 0) {
1476 if (udev
->state
== USB_STATE_SUSPENDED
)
1477 status
= usb_resume_both(udev
,
1480 intf
->pm_usage_cnt
-= inc_usage_cnt
;
1482 udev
->last_busy
= jiffies
;
1483 } else if (inc_usage_cnt
<= 0 && intf
->pm_usage_cnt
<= 0) {
1484 status
= usb_suspend_both(udev
, PMSG_AUTO_SUSPEND
);
1487 usb_pm_unlock(udev
);
1492 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1493 * @intf: the usb_interface whose counter should be decremented
1495 * This routine should be called by an interface driver when it is
1496 * finished using @intf and wants to allow it to autosuspend. A typical
1497 * example would be a character-device driver when its device file is
1500 * The routine decrements @intf's usage counter. When the counter reaches
1501 * 0, a delayed autosuspend request for @intf's device is queued. When
1502 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1503 * the other usage counters for the sibling interfaces and @intf's
1504 * usb_device, the device and all its interfaces will be autosuspended.
1506 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1507 * core will not change its value other than the increment and decrement
1508 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1509 * may use this simple counter-oriented discipline or may set the value
1512 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1513 * take place only if the device's remote-wakeup facility is enabled.
1515 * Suspend method calls queued by this routine can arrive at any time
1516 * while @intf is resumed and its usage counter is equal to 0. They are
1517 * not protected by the usb_device's lock but only by its pm_mutex.
1518 * Drivers must provide their own synchronization.
1520 * This routine can run only in process context.
1522 void usb_autopm_put_interface(struct usb_interface
*intf
)
1526 status
= usb_autopm_do_interface(intf
, -1);
1527 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1528 __func__
, status
, intf
->pm_usage_cnt
);
1530 EXPORT_SYMBOL_GPL(usb_autopm_put_interface
);
1533 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1534 * @intf: the usb_interface whose counter should be decremented
1536 * This routine does essentially the same thing as
1537 * usb_autopm_put_interface(): it decrements @intf's usage counter and
1538 * queues a delayed autosuspend request if the counter is <= 0. The
1539 * difference is that it does not acquire the device's pm_mutex;
1540 * callers must handle all synchronization issues themselves.
1542 * Typically a driver would call this routine during an URB's completion
1543 * handler, if no more URBs were pending.
1545 * This routine can run in atomic context.
1547 void usb_autopm_put_interface_async(struct usb_interface
*intf
)
1549 struct usb_device
*udev
= interface_to_usbdev(intf
);
1552 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
1555 udev
->last_busy
= jiffies
;
1556 --intf
->pm_usage_cnt
;
1557 if (udev
->autosuspend_disabled
|| udev
->autosuspend_delay
< 0)
1559 else if (intf
->pm_usage_cnt
<= 0 &&
1560 !timer_pending(&udev
->autosuspend
.timer
)) {
1561 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1562 round_jiffies_up_relative(
1563 udev
->autosuspend_delay
));
1566 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1567 __func__
, status
, intf
->pm_usage_cnt
);
1569 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async
);
1572 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1573 * @intf: the usb_interface whose counter should be incremented
1575 * This routine should be called by an interface driver when it wants to
1576 * use @intf and needs to guarantee that it is not suspended. In addition,
1577 * the routine prevents @intf from being autosuspended subsequently. (Note
1578 * that this will not prevent suspend events originating in the PM core.)
1579 * This prevention will persist until usb_autopm_put_interface() is called
1580 * or @intf is unbound. A typical example would be a character-device
1581 * driver when its device file is opened.
1584 * The routine increments @intf's usage counter. (However if the
1585 * autoresume fails then the counter is re-decremented.) So long as the
1586 * counter is greater than 0, autosuspend will not be allowed for @intf
1587 * or its usb_device. When the driver is finished using @intf it should
1588 * call usb_autopm_put_interface() to decrement the usage counter and
1589 * queue a delayed autosuspend request (if the counter is <= 0).
1592 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1593 * core will not change its value other than the increment and decrement
1594 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1595 * may use this simple counter-oriented discipline or may set the value
1598 * Resume method calls generated by this routine can arrive at any time
1599 * while @intf is suspended. They are not protected by the usb_device's
1600 * lock but only by its pm_mutex. Drivers must provide their own
1603 * This routine can run only in process context.
1605 int usb_autopm_get_interface(struct usb_interface
*intf
)
1609 status
= usb_autopm_do_interface(intf
, 1);
1610 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1611 __func__
, status
, intf
->pm_usage_cnt
);
1614 EXPORT_SYMBOL_GPL(usb_autopm_get_interface
);
1617 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1618 * @intf: the usb_interface whose counter should be incremented
1620 * This routine does much the same thing as
1621 * usb_autopm_get_interface(): it increments @intf's usage counter and
1622 * queues an autoresume request if the result is > 0. The differences
1623 * are that it does not acquire the device's pm_mutex (callers must
1624 * handle all synchronization issues themselves), and it does not
1625 * autoresume the device directly (it only queues a request). After a
1626 * successful call, the device will generally not yet be resumed.
1628 * This routine can run in atomic context.
1630 int usb_autopm_get_interface_async(struct usb_interface
*intf
)
1632 struct usb_device
*udev
= interface_to_usbdev(intf
);
1635 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1637 else if (udev
->autoresume_disabled
)
1639 else if (++intf
->pm_usage_cnt
> 0 && udev
->state
== USB_STATE_SUSPENDED
)
1640 queue_work(ksuspend_usb_wq
, &udev
->autoresume
);
1641 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1642 __func__
, status
, intf
->pm_usage_cnt
);
1645 EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async
);
1648 * usb_autopm_set_interface - set a USB interface's autosuspend state
1649 * @intf: the usb_interface whose state should be set
1651 * This routine sets the autosuspend state of @intf's device according
1652 * to @intf's usage counter, which the caller must have set previously.
1653 * If the counter is <= 0, the device is autosuspended (if it isn't
1654 * already suspended and if nothing else prevents the autosuspend). If
1655 * the counter is > 0, the device is autoresumed (if it isn't already
1658 int usb_autopm_set_interface(struct usb_interface
*intf
)
1662 status
= usb_autopm_do_interface(intf
, 0);
1663 dev_vdbg(&intf
->dev
, "%s: status %d cnt %d\n",
1664 __func__
, status
, intf
->pm_usage_cnt
);
1667 EXPORT_SYMBOL_GPL(usb_autopm_set_interface
);
1671 void usb_autosuspend_work(struct work_struct
*work
)
1674 void usb_autoresume_work(struct work_struct
*work
)
1677 #endif /* CONFIG_USB_SUSPEND */
1680 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1681 * @udev: the usb_device to suspend
1682 * @msg: Power Management message describing this state transition
1684 * This routine handles external suspend requests: ones not generated
1685 * internally by a USB driver (autosuspend) but rather coming from the user
1686 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1687 * out regardless of @udev's usage counter or those of its interfaces,
1688 * and regardless of whether or not remote wakeup is enabled. Of course,
1689 * interface drivers still have the option of failing the suspend (if
1690 * there are unsuspended children, for example).
1692 * The caller must hold @udev's device lock.
1694 int usb_external_suspend_device(struct usb_device
*udev
, pm_message_t msg
)
1698 do_unbind_rebind(udev
, DO_UNBIND
);
1701 status
= usb_suspend_both(udev
, msg
);
1702 usb_pm_unlock(udev
);
1707 * usb_external_resume_device - external resume of a USB device and its interfaces
1708 * @udev: the usb_device to resume
1709 * @msg: Power Management message describing this state transition
1711 * This routine handles external resume requests: ones not generated
1712 * internally by a USB driver (autoresume) but rather coming from the user
1713 * (via sysfs), the PM core (system resume), or the device itself (remote
1714 * wakeup). @udev's usage counter is unaffected.
1716 * The caller must hold @udev's device lock.
1718 int usb_external_resume_device(struct usb_device
*udev
, pm_message_t msg
)
1724 status
= usb_resume_both(udev
, msg
);
1725 udev
->last_busy
= jiffies
;
1726 usb_pm_unlock(udev
);
1728 do_unbind_rebind(udev
, DO_REBIND
);
1730 /* Now that the device is awake, we can start trying to autosuspend
1733 usb_try_autosuspend_device(udev
);
1737 int usb_suspend(struct device
*dev
, pm_message_t msg
)
1739 struct usb_device
*udev
;
1741 udev
= to_usb_device(dev
);
1743 /* If udev is already suspended, we can skip this suspend and
1744 * we should also skip the upcoming system resume. High-speed
1745 * root hubs are an exception; they need to resume whenever the
1746 * system wakes up in order for USB-PERSIST port handover to work
1749 if (udev
->state
== USB_STATE_SUSPENDED
) {
1750 if (udev
->parent
|| udev
->speed
!= USB_SPEED_HIGH
)
1751 udev
->skip_sys_resume
= 1;
1755 udev
->skip_sys_resume
= 0;
1756 return usb_external_suspend_device(udev
, msg
);
1759 int usb_resume(struct device
*dev
, pm_message_t msg
)
1761 struct usb_device
*udev
;
1763 udev
= to_usb_device(dev
);
1765 /* If udev->skip_sys_resume is set then udev was already suspended
1766 * when the system sleep started, so we don't want to resume it
1767 * during this system wakeup.
1769 if (udev
->skip_sys_resume
)
1771 return usb_external_resume_device(udev
, msg
);
1774 #endif /* CONFIG_PM */
1776 struct bus_type usb_bus_type
= {
1778 .match
= usb_device_match
,
1779 .uevent
= usb_uevent
,