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/workqueue.h>
31 static int usb_match_one_id(struct usb_interface
*interface
,
32 const struct usb_device_id
*id
);
35 struct list_head node
;
36 struct usb_device_id id
;
42 * Adds a new dynamic USBdevice ID to this driver,
43 * and cause the driver to probe for all devices again.
45 static ssize_t
store_new_id(struct device_driver
*driver
,
46 const char *buf
, size_t count
)
48 struct usb_driver
*usb_drv
= to_usb_driver(driver
);
49 struct usb_dynid
*dynid
;
55 fields
= sscanf(buf
, "%x %x", &idVendor
, &idProduct
);
59 dynid
= kzalloc(sizeof(*dynid
), GFP_KERNEL
);
63 INIT_LIST_HEAD(&dynid
->node
);
64 dynid
->id
.idVendor
= idVendor
;
65 dynid
->id
.idProduct
= idProduct
;
66 dynid
->id
.match_flags
= USB_DEVICE_ID_MATCH_DEVICE
;
68 spin_lock(&usb_drv
->dynids
.lock
);
69 list_add_tail(&usb_drv
->dynids
.list
, &dynid
->node
);
70 spin_unlock(&usb_drv
->dynids
.lock
);
72 if (get_driver(driver
)) {
73 retval
= driver_attach(driver
);
81 static DRIVER_ATTR(new_id
, S_IWUSR
, NULL
, store_new_id
);
83 static int usb_create_newid_file(struct usb_driver
*usb_drv
)
87 if (usb_drv
->no_dynamic_id
)
90 if (usb_drv
->probe
!= NULL
)
91 error
= sysfs_create_file(&usb_drv
->drvwrap
.driver
.kobj
,
92 &driver_attr_new_id
.attr
);
97 static void usb_remove_newid_file(struct usb_driver
*usb_drv
)
99 if (usb_drv
->no_dynamic_id
)
102 if (usb_drv
->probe
!= NULL
)
103 sysfs_remove_file(&usb_drv
->drvwrap
.driver
.kobj
,
104 &driver_attr_new_id
.attr
);
107 static void usb_free_dynids(struct usb_driver
*usb_drv
)
109 struct usb_dynid
*dynid
, *n
;
111 spin_lock(&usb_drv
->dynids
.lock
);
112 list_for_each_entry_safe(dynid
, n
, &usb_drv
->dynids
.list
, node
) {
113 list_del(&dynid
->node
);
116 spin_unlock(&usb_drv
->dynids
.lock
);
119 static inline int usb_create_newid_file(struct usb_driver
*usb_drv
)
124 static void usb_remove_newid_file(struct usb_driver
*usb_drv
)
128 static inline void usb_free_dynids(struct usb_driver
*usb_drv
)
133 static const struct usb_device_id
*usb_match_dynamic_id(struct usb_interface
*intf
,
134 struct usb_driver
*drv
)
136 struct usb_dynid
*dynid
;
138 spin_lock(&drv
->dynids
.lock
);
139 list_for_each_entry(dynid
, &drv
->dynids
.list
, node
) {
140 if (usb_match_one_id(intf
, &dynid
->id
)) {
141 spin_unlock(&drv
->dynids
.lock
);
145 spin_unlock(&drv
->dynids
.lock
);
150 /* called from driver core with dev locked */
151 static int usb_probe_device(struct device
*dev
)
153 struct usb_device_driver
*udriver
= to_usb_device_driver(dev
->driver
);
154 struct usb_device
*udev
;
157 dev_dbg(dev
, "%s\n", __FUNCTION__
);
159 if (!is_usb_device(dev
)) /* Sanity check */
162 udev
= to_usb_device(dev
);
164 /* TODO: Add real matching code */
166 /* The device should always appear to be in use
167 * unless the driver suports autosuspend.
169 udev
->pm_usage_cnt
= !(udriver
->supports_autosuspend
);
171 error
= udriver
->probe(udev
);
175 /* called from driver core with dev locked */
176 static int usb_unbind_device(struct device
*dev
)
178 struct usb_device_driver
*udriver
= to_usb_device_driver(dev
->driver
);
180 udriver
->disconnect(to_usb_device(dev
));
185 /* called from driver core with dev locked */
186 static int usb_probe_interface(struct device
*dev
)
188 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
189 struct usb_interface
*intf
;
190 struct usb_device
*udev
;
191 const struct usb_device_id
*id
;
194 dev_dbg(dev
, "%s\n", __FUNCTION__
);
196 if (is_usb_device(dev
)) /* Sanity check */
199 intf
= to_usb_interface(dev
);
200 udev
= interface_to_usbdev(intf
);
202 id
= usb_match_id(intf
, driver
->id_table
);
204 id
= usb_match_dynamic_id(intf
, driver
);
206 dev_dbg(dev
, "%s - got id\n", __FUNCTION__
);
208 error
= usb_autoresume_device(udev
, 1);
212 /* Interface "power state" doesn't correspond to any hardware
213 * state whatsoever. We use it to record when it's bound to
214 * a driver that may start I/0: it's not frozen/quiesced.
217 intf
->condition
= USB_INTERFACE_BINDING
;
219 /* The interface should always appear to be in use
220 * unless the driver suports autosuspend.
222 intf
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
224 error
= driver
->probe(intf
, id
);
227 intf
->needs_remote_wakeup
= 0;
228 intf
->condition
= USB_INTERFACE_UNBOUND
;
230 intf
->condition
= USB_INTERFACE_BOUND
;
232 usb_autosuspend_device(udev
, 1);
238 /* called from driver core with dev locked */
239 static int usb_unbind_interface(struct device
*dev
)
241 struct usb_driver
*driver
= to_usb_driver(dev
->driver
);
242 struct usb_interface
*intf
= to_usb_interface(dev
);
243 struct usb_device
*udev
;
246 intf
->condition
= USB_INTERFACE_UNBINDING
;
248 /* Autoresume for set_interface call below */
249 udev
= interface_to_usbdev(intf
);
250 error
= usb_autoresume_device(udev
, 1);
252 /* release all urbs for this interface */
253 usb_disable_interface(interface_to_usbdev(intf
), intf
);
255 driver
->disconnect(intf
);
257 /* reset other interface state */
258 usb_set_interface(interface_to_usbdev(intf
),
259 intf
->altsetting
[0].desc
.bInterfaceNumber
,
261 usb_set_intfdata(intf
, NULL
);
263 intf
->condition
= USB_INTERFACE_UNBOUND
;
265 intf
->needs_remote_wakeup
= 0;
268 usb_autosuspend_device(udev
, 1);
274 * usb_driver_claim_interface - bind a driver to an interface
275 * @driver: the driver to be bound
276 * @iface: the interface to which it will be bound; must be in the
277 * usb device's active configuration
278 * @priv: driver data associated with that interface
280 * This is used by usb device drivers that need to claim more than one
281 * interface on a device when probing (audio and acm are current examples).
282 * No device driver should directly modify internal usb_interface or
283 * usb_device structure members.
285 * Few drivers should need to use this routine, since the most natural
286 * way to bind to an interface is to return the private data from
287 * the driver's probe() method.
289 * Callers must own the device lock and the driver model's usb_bus_type.subsys
290 * writelock. So driver probe() entries don't need extra locking,
291 * but other call contexts may need to explicitly claim those locks.
293 int usb_driver_claim_interface(struct usb_driver
*driver
,
294 struct usb_interface
*iface
, void* priv
)
296 struct device
*dev
= &iface
->dev
;
297 struct usb_device
*udev
= interface_to_usbdev(iface
);
303 dev
->driver
= &driver
->drvwrap
.driver
;
304 usb_set_intfdata(iface
, priv
);
307 iface
->condition
= USB_INTERFACE_BOUND
;
309 iface
->pm_usage_cnt
= !(driver
->supports_autosuspend
);
312 /* if interface was already added, bind now; else let
313 * the future device_add() bind it, bypassing probe()
315 if (device_is_registered(dev
))
316 retval
= device_bind_driver(dev
);
320 EXPORT_SYMBOL(usb_driver_claim_interface
);
323 * usb_driver_release_interface - unbind a driver from an interface
324 * @driver: the driver to be unbound
325 * @iface: the interface from which it will be unbound
327 * This can be used by drivers to release an interface without waiting
328 * for their disconnect() methods to be called. In typical cases this
329 * also causes the driver disconnect() method to be called.
331 * This call is synchronous, and may not be used in an interrupt context.
332 * Callers must own the device lock and the driver model's usb_bus_type.subsys
333 * writelock. So driver disconnect() entries don't need extra locking,
334 * but other call contexts may need to explicitly claim those locks.
336 void usb_driver_release_interface(struct usb_driver
*driver
,
337 struct usb_interface
*iface
)
339 struct device
*dev
= &iface
->dev
;
340 struct usb_device
*udev
= interface_to_usbdev(iface
);
342 /* this should never happen, don't release something that's not ours */
343 if (!dev
->driver
|| dev
->driver
!= &driver
->drvwrap
.driver
)
346 /* don't release from within disconnect() */
347 if (iface
->condition
!= USB_INTERFACE_BOUND
)
350 /* don't release if the interface hasn't been added yet */
351 if (device_is_registered(dev
)) {
352 iface
->condition
= USB_INTERFACE_UNBINDING
;
353 device_release_driver(dev
);
357 usb_set_intfdata(iface
, NULL
);
360 iface
->condition
= USB_INTERFACE_UNBOUND
;
361 mark_quiesced(iface
);
362 iface
->needs_remote_wakeup
= 0;
365 EXPORT_SYMBOL(usb_driver_release_interface
);
367 /* returns 0 if no match, 1 if match */
368 static int usb_match_one_id(struct usb_interface
*interface
,
369 const struct usb_device_id
*id
)
371 struct usb_host_interface
*intf
;
372 struct usb_device
*dev
;
374 /* proc_connectinfo in devio.c may call us with id == NULL. */
378 intf
= interface
->cur_altsetting
;
379 dev
= interface_to_usbdev(interface
);
381 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_VENDOR
) &&
382 id
->idVendor
!= le16_to_cpu(dev
->descriptor
.idVendor
))
385 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_PRODUCT
) &&
386 id
->idProduct
!= le16_to_cpu(dev
->descriptor
.idProduct
))
389 /* No need to test id->bcdDevice_lo != 0, since 0 is never
390 greater than any unsigned number. */
391 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_LO
) &&
392 (id
->bcdDevice_lo
> le16_to_cpu(dev
->descriptor
.bcdDevice
)))
395 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_HI
) &&
396 (id
->bcdDevice_hi
< le16_to_cpu(dev
->descriptor
.bcdDevice
)))
399 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_CLASS
) &&
400 (id
->bDeviceClass
!= dev
->descriptor
.bDeviceClass
))
403 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_SUBCLASS
) &&
404 (id
->bDeviceSubClass
!= dev
->descriptor
.bDeviceSubClass
))
407 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_DEV_PROTOCOL
) &&
408 (id
->bDeviceProtocol
!= dev
->descriptor
.bDeviceProtocol
))
411 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_CLASS
) &&
412 (id
->bInterfaceClass
!= intf
->desc
.bInterfaceClass
))
415 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_SUBCLASS
) &&
416 (id
->bInterfaceSubClass
!= intf
->desc
.bInterfaceSubClass
))
419 if ((id
->match_flags
& USB_DEVICE_ID_MATCH_INT_PROTOCOL
) &&
420 (id
->bInterfaceProtocol
!= intf
->desc
.bInterfaceProtocol
))
426 * usb_match_id - find first usb_device_id matching device or interface
427 * @interface: the interface of interest
428 * @id: array of usb_device_id structures, terminated by zero entry
430 * usb_match_id searches an array of usb_device_id's and returns
431 * the first one matching the device or interface, or null.
432 * This is used when binding (or rebinding) a driver to an interface.
433 * Most USB device drivers will use this indirectly, through the usb core,
434 * but some layered driver frameworks use it directly.
435 * These device tables are exported with MODULE_DEVICE_TABLE, through
436 * modutils, to support the driver loading functionality of USB hotplugging.
440 * The "match_flags" element in a usb_device_id controls which
441 * members are used. If the corresponding bit is set, the
442 * value in the device_id must match its corresponding member
443 * in the device or interface descriptor, or else the device_id
446 * "driver_info" is normally used only by device drivers,
447 * but you can create a wildcard "matches anything" usb_device_id
448 * as a driver's "modules.usbmap" entry if you provide an id with
449 * only a nonzero "driver_info" field. If you do this, the USB device
450 * driver's probe() routine should use additional intelligence to
451 * decide whether to bind to the specified interface.
453 * What Makes Good usb_device_id Tables:
455 * The match algorithm is very simple, so that intelligence in
456 * driver selection must come from smart driver id records.
457 * Unless you have good reasons to use another selection policy,
458 * provide match elements only in related groups, and order match
459 * specifiers from specific to general. Use the macros provided
460 * for that purpose if you can.
462 * The most specific match specifiers use device descriptor
463 * data. These are commonly used with product-specific matches;
464 * the USB_DEVICE macro lets you provide vendor and product IDs,
465 * and you can also match against ranges of product revisions.
466 * These are widely used for devices with application or vendor
467 * specific bDeviceClass values.
469 * Matches based on device class/subclass/protocol specifications
470 * are slightly more general; use the USB_DEVICE_INFO macro, or
471 * its siblings. These are used with single-function devices
472 * where bDeviceClass doesn't specify that each interface has
475 * Matches based on interface class/subclass/protocol are the
476 * most general; they let drivers bind to any interface on a
477 * multiple-function device. Use the USB_INTERFACE_INFO
478 * macro, or its siblings, to match class-per-interface style
479 * devices (as recorded in bDeviceClass).
481 * Within those groups, remember that not all combinations are
482 * meaningful. For example, don't give a product version range
483 * without vendor and product IDs; or specify a protocol without
484 * its associated class and subclass.
486 const struct usb_device_id
*usb_match_id(struct usb_interface
*interface
,
487 const struct usb_device_id
*id
)
489 /* proc_connectinfo in devio.c may call us with id == NULL. */
493 /* It is important to check that id->driver_info is nonzero,
494 since an entry that is all zeroes except for a nonzero
495 id->driver_info is the way to create an entry that
496 indicates that the driver want to examine every
497 device and interface. */
498 for (; id
->idVendor
|| id
->bDeviceClass
|| id
->bInterfaceClass
||
499 id
->driver_info
; id
++) {
500 if (usb_match_one_id(interface
, id
))
506 EXPORT_SYMBOL_GPL_FUTURE(usb_match_id
);
508 int usb_device_match(struct device
*dev
, struct device_driver
*drv
)
510 /* devices and interfaces are handled separately */
511 if (is_usb_device(dev
)) {
513 /* interface drivers never match devices */
514 if (!is_usb_device_driver(drv
))
517 /* TODO: Add real matching code */
521 struct usb_interface
*intf
;
522 struct usb_driver
*usb_drv
;
523 const struct usb_device_id
*id
;
525 /* device drivers never match interfaces */
526 if (is_usb_device_driver(drv
))
529 intf
= to_usb_interface(dev
);
530 usb_drv
= to_usb_driver(drv
);
532 id
= usb_match_id(intf
, usb_drv
->id_table
);
536 id
= usb_match_dynamic_id(intf
, usb_drv
);
544 #ifdef CONFIG_HOTPLUG
547 * This sends an uevent to userspace, typically helping to load driver
548 * or other modules, configure the device, and more. Drivers can provide
549 * a MODULE_DEVICE_TABLE to help with module loading subtasks.
551 * We're called either from khubd (the typical case) or from root hub
552 * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle
553 * delays in event delivery. Use sysfs (and DEVPATH) to make sure the
554 * device (and this configuration!) are still present.
556 static int usb_uevent(struct device
*dev
, char **envp
, int num_envp
,
557 char *buffer
, int buffer_size
)
559 struct usb_interface
*intf
;
560 struct usb_device
*usb_dev
;
561 struct usb_host_interface
*alt
;
568 /* driver is often null here; dev_dbg() would oops */
569 pr_debug ("usb %s: uevent\n", dev
->bus_id
);
571 if (is_usb_device(dev
)) {
572 usb_dev
= to_usb_device(dev
);
575 intf
= to_usb_interface(dev
);
576 usb_dev
= interface_to_usbdev(intf
);
577 alt
= intf
->cur_altsetting
;
580 if (usb_dev
->devnum
< 0) {
581 pr_debug ("usb %s: already deleted?\n", dev
->bus_id
);
585 pr_debug ("usb %s: bus removed?\n", dev
->bus_id
);
589 #ifdef CONFIG_USB_DEVICEFS
590 /* If this is available, userspace programs can directly read
591 * all the device descriptors we don't tell them about. Or
592 * even act as usermode drivers.
594 * FIXME reduce hardwired intelligence here
596 if (add_uevent_var(envp
, num_envp
, &i
,
597 buffer
, buffer_size
, &length
,
598 "DEVICE=/proc/bus/usb/%03d/%03d",
599 usb_dev
->bus
->busnum
, usb_dev
->devnum
))
603 /* per-device configurations are common */
604 if (add_uevent_var(envp
, num_envp
, &i
,
605 buffer
, buffer_size
, &length
,
607 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
608 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
609 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
)))
612 /* class-based driver binding models */
613 if (add_uevent_var(envp
, num_envp
, &i
,
614 buffer
, buffer_size
, &length
,
616 usb_dev
->descriptor
.bDeviceClass
,
617 usb_dev
->descriptor
.bDeviceSubClass
,
618 usb_dev
->descriptor
.bDeviceProtocol
))
621 if (!is_usb_device(dev
)) {
623 if (add_uevent_var(envp
, num_envp
, &i
,
624 buffer
, buffer_size
, &length
,
625 "INTERFACE=%d/%d/%d",
626 alt
->desc
.bInterfaceClass
,
627 alt
->desc
.bInterfaceSubClass
,
628 alt
->desc
.bInterfaceProtocol
))
631 if (add_uevent_var(envp
, num_envp
, &i
,
632 buffer
, buffer_size
, &length
,
633 "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
634 le16_to_cpu(usb_dev
->descriptor
.idVendor
),
635 le16_to_cpu(usb_dev
->descriptor
.idProduct
),
636 le16_to_cpu(usb_dev
->descriptor
.bcdDevice
),
637 usb_dev
->descriptor
.bDeviceClass
,
638 usb_dev
->descriptor
.bDeviceSubClass
,
639 usb_dev
->descriptor
.bDeviceProtocol
,
640 alt
->desc
.bInterfaceClass
,
641 alt
->desc
.bInterfaceSubClass
,
642 alt
->desc
.bInterfaceProtocol
))
653 static int usb_uevent(struct device
*dev
, char **envp
,
654 int num_envp
, char *buffer
, int buffer_size
)
659 #endif /* CONFIG_HOTPLUG */
662 * usb_register_device_driver - register a USB device (not interface) driver
663 * @new_udriver: USB operations for the device driver
664 * @owner: module owner of this driver.
666 * Registers a USB device driver with the USB core. The list of
667 * unattached devices will be rescanned whenever a new driver is
668 * added, allowing the new driver to attach to any recognized devices.
669 * Returns a negative error code on failure and 0 on success.
671 int usb_register_device_driver(struct usb_device_driver
*new_udriver
,
672 struct module
*owner
)
679 new_udriver
->drvwrap
.for_devices
= 1;
680 new_udriver
->drvwrap
.driver
.name
= (char *) new_udriver
->name
;
681 new_udriver
->drvwrap
.driver
.bus
= &usb_bus_type
;
682 new_udriver
->drvwrap
.driver
.probe
= usb_probe_device
;
683 new_udriver
->drvwrap
.driver
.remove
= usb_unbind_device
;
684 new_udriver
->drvwrap
.driver
.owner
= owner
;
686 retval
= driver_register(&new_udriver
->drvwrap
.driver
);
689 pr_info("%s: registered new device driver %s\n",
690 usbcore_name
, new_udriver
->name
);
691 usbfs_update_special();
693 printk(KERN_ERR
"%s: error %d registering device "
695 usbcore_name
, retval
, new_udriver
->name
);
700 EXPORT_SYMBOL_GPL(usb_register_device_driver
);
703 * usb_deregister_device_driver - unregister a USB device (not interface) driver
704 * @udriver: USB operations of the device driver to unregister
705 * Context: must be able to sleep
707 * Unlinks the specified driver from the internal USB driver list.
709 void usb_deregister_device_driver(struct usb_device_driver
*udriver
)
711 pr_info("%s: deregistering device driver %s\n",
712 usbcore_name
, udriver
->name
);
714 driver_unregister(&udriver
->drvwrap
.driver
);
715 usbfs_update_special();
717 EXPORT_SYMBOL_GPL(usb_deregister_device_driver
);
720 * usb_register_driver - register a USB interface driver
721 * @new_driver: USB operations for the interface driver
722 * @owner: module owner of this driver.
724 * Registers a USB interface driver with the USB core. The list of
725 * unattached interfaces will be rescanned whenever a new driver is
726 * added, allowing the new driver to attach to any recognized interfaces.
727 * Returns a negative error code on failure and 0 on success.
729 * NOTE: if you want your driver to use the USB major number, you must call
730 * usb_register_dev() to enable that functionality. This function no longer
731 * takes care of that.
733 int usb_register_driver(struct usb_driver
*new_driver
, struct module
*owner
)
740 new_driver
->drvwrap
.for_devices
= 0;
741 new_driver
->drvwrap
.driver
.name
= (char *) new_driver
->name
;
742 new_driver
->drvwrap
.driver
.bus
= &usb_bus_type
;
743 new_driver
->drvwrap
.driver
.probe
= usb_probe_interface
;
744 new_driver
->drvwrap
.driver
.remove
= usb_unbind_interface
;
745 new_driver
->drvwrap
.driver
.owner
= owner
;
746 spin_lock_init(&new_driver
->dynids
.lock
);
747 INIT_LIST_HEAD(&new_driver
->dynids
.list
);
749 retval
= driver_register(&new_driver
->drvwrap
.driver
);
752 pr_info("%s: registered new interface driver %s\n",
753 usbcore_name
, new_driver
->name
);
754 usbfs_update_special();
755 usb_create_newid_file(new_driver
);
757 printk(KERN_ERR
"%s: error %d registering interface "
759 usbcore_name
, retval
, new_driver
->name
);
764 EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver
);
767 * usb_deregister - unregister a USB interface driver
768 * @driver: USB operations of the interface driver to unregister
769 * Context: must be able to sleep
771 * Unlinks the specified driver from the internal USB driver list.
773 * NOTE: If you called usb_register_dev(), you still need to call
774 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
775 * this * call will no longer do it for you.
777 void usb_deregister(struct usb_driver
*driver
)
779 pr_info("%s: deregistering interface driver %s\n",
780 usbcore_name
, driver
->name
);
782 usb_remove_newid_file(driver
);
783 usb_free_dynids(driver
);
784 driver_unregister(&driver
->drvwrap
.driver
);
786 usbfs_update_special();
788 EXPORT_SYMBOL_GPL_FUTURE(usb_deregister
);
792 /* Caller has locked udev's pm_mutex */
793 static int suspend_device(struct usb_device
*udev
, pm_message_t msg
)
795 struct usb_device_driver
*udriver
;
798 if (udev
->state
== USB_STATE_NOTATTACHED
||
799 udev
->state
== USB_STATE_SUSPENDED
)
802 /* For devices that don't have a driver, we do a standard suspend. */
803 if (udev
->dev
.driver
== NULL
) {
804 udev
->do_remote_wakeup
= 0;
805 status
= usb_port_suspend(udev
);
809 udriver
= to_usb_device_driver(udev
->dev
.driver
);
810 status
= udriver
->suspend(udev
, msg
);
813 // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
815 udev
->dev
.power
.power_state
.event
= msg
.event
;
819 /* Caller has locked udev's pm_mutex */
820 static int resume_device(struct usb_device
*udev
)
822 struct usb_device_driver
*udriver
;
825 if (udev
->state
== USB_STATE_NOTATTACHED
||
826 udev
->state
!= USB_STATE_SUSPENDED
)
829 /* Can't resume it if it doesn't have a driver. */
830 if (udev
->dev
.driver
== NULL
) {
835 udriver
= to_usb_device_driver(udev
->dev
.driver
);
836 status
= udriver
->resume(udev
);
839 // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
841 udev
->dev
.power
.power_state
.event
= PM_EVENT_ON
;
845 /* Caller has locked intf's usb_device's pm mutex */
846 static int suspend_interface(struct usb_interface
*intf
, pm_message_t msg
)
848 struct usb_driver
*driver
;
851 /* with no hardware, USB interfaces only use FREEZE and ON states */
852 if (interface_to_usbdev(intf
)->state
== USB_STATE_NOTATTACHED
||
856 if (intf
->condition
== USB_INTERFACE_UNBOUND
) /* This can't happen */
858 driver
= to_usb_driver(intf
->dev
.driver
);
860 if (driver
->suspend
&& driver
->resume
) {
861 status
= driver
->suspend(intf
, msg
);
864 else if (!interface_to_usbdev(intf
)->auto_pm
)
865 dev_err(&intf
->dev
, "%s error %d\n",
868 // FIXME else if there's no suspend method, disconnect...
869 // Not possible if auto_pm is set...
870 dev_warn(&intf
->dev
, "no suspend for driver %s?\n",
876 // dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
878 intf
->dev
.power
.power_state
.event
= msg
.event
;
882 /* Caller has locked intf's usb_device's pm_mutex */
883 static int resume_interface(struct usb_interface
*intf
)
885 struct usb_driver
*driver
;
888 if (interface_to_usbdev(intf
)->state
== USB_STATE_NOTATTACHED
||
892 /* Don't let autoresume interfere with unbinding */
893 if (intf
->condition
== USB_INTERFACE_UNBINDING
)
896 /* Can't resume it if it doesn't have a driver. */
897 if (intf
->condition
== USB_INTERFACE_UNBOUND
) {
901 driver
= to_usb_driver(intf
->dev
.driver
);
903 if (driver
->resume
) {
904 status
= driver
->resume(intf
);
906 dev_err(&intf
->dev
, "%s error %d\n",
911 dev_warn(&intf
->dev
, "no resume for driver %s?\n",
917 // dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
919 intf
->dev
.power
.power_state
.event
= PM_EVENT_ON
;
924 * usb_suspend_both - suspend a USB device and its interfaces
925 * @udev: the usb_device to suspend
926 * @msg: Power Management message describing this state transition
928 * This is the central routine for suspending USB devices. It calls the
929 * suspend methods for all the interface drivers in @udev and then calls
930 * the suspend method for @udev itself. If an error occurs at any stage,
931 * all the interfaces which were suspended are resumed so that they remain
932 * in the same state as the device.
934 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
935 * checks first to make sure that neither the device itself or any of its
936 * active interfaces is in use (pm_usage_cnt is greater than 0). If they
937 * are, the autosuspend fails.
939 * If the suspend succeeds, the routine recursively queues an autosuspend
940 * request for @udev's parent device, thereby propagating the change up
941 * the device tree. If all of the parent's children are now suspended,
942 * the parent will autosuspend in turn.
944 * The suspend method calls are subject to mutual exclusion under control
945 * of @udev's pm_mutex. Many of these calls are also under the protection
946 * of @udev's device lock (including all requests originating outside the
947 * USB subsystem), but autosuspend requests generated by a child device or
948 * interface driver may not be. Usbcore will insure that the method calls
949 * do not arrive during bind, unbind, or reset operations. However, drivers
950 * must be prepared to handle suspend calls arriving at unpredictable times.
951 * The only way to block such calls is to do an autoresume (preventing
952 * autosuspends) while holding @udev's device lock (preventing outside
955 * The caller must hold @udev->pm_mutex.
957 * This routine can run only in process context.
959 int usb_suspend_both(struct usb_device
*udev
, pm_message_t msg
)
963 struct usb_interface
*intf
;
964 struct usb_device
*parent
= udev
->parent
;
966 cancel_delayed_work(&udev
->autosuspend
);
967 if (udev
->state
== USB_STATE_NOTATTACHED
)
969 if (udev
->state
== USB_STATE_SUSPENDED
)
972 udev
->do_remote_wakeup
= device_may_wakeup(&udev
->dev
);
974 /* For autosuspend, fail fast if anything is in use.
975 * Also fail if any interfaces require remote wakeup but it
976 * isn't available. */
978 if (udev
->pm_usage_cnt
> 0)
980 if (udev
->actconfig
) {
981 for (; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
982 intf
= udev
->actconfig
->interface
[i
];
983 if (!is_active(intf
))
985 if (intf
->pm_usage_cnt
> 0)
987 if (intf
->needs_remote_wakeup
&&
988 !udev
->do_remote_wakeup
) {
990 "remote wakeup needed for autosuspend\n");
998 /* Suspend all the interfaces and then udev itself */
999 if (udev
->actconfig
) {
1000 for (; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1001 intf
= udev
->actconfig
->interface
[i
];
1002 status
= suspend_interface(intf
, msg
);
1008 status
= suspend_device(udev
, msg
);
1010 /* If the suspend failed, resume interfaces that did get suspended */
1013 intf
= udev
->actconfig
->interface
[i
];
1014 resume_interface(intf
);
1017 /* If the suspend succeeded, propagate it up the tree */
1019 usb_autosuspend_device(parent
, 0);
1021 // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
1026 * usb_resume_both - resume a USB device and its interfaces
1027 * @udev: the usb_device to resume
1029 * This is the central routine for resuming USB devices. It calls the
1030 * the resume method for @udev and then calls the resume methods for all
1031 * the interface drivers in @udev.
1033 * Before starting the resume, the routine calls itself recursively for
1034 * the parent device of @udev, thereby propagating the change up the device
1035 * tree and assuring that @udev will be able to resume. If the parent is
1036 * unable to resume successfully, the routine fails.
1038 * The resume method calls are subject to mutual exclusion under control
1039 * of @udev's pm_mutex. Many of these calls are also under the protection
1040 * of @udev's device lock (including all requests originating outside the
1041 * USB subsystem), but autoresume requests generated by a child device or
1042 * interface driver may not be. Usbcore will insure that the method calls
1043 * do not arrive during bind, unbind, or reset operations. However, drivers
1044 * must be prepared to handle resume calls arriving at unpredictable times.
1045 * The only way to block such calls is to do an autoresume (preventing
1046 * other autoresumes) while holding @udev's device lock (preventing outside
1049 * The caller must hold @udev->pm_mutex.
1051 * This routine can run only in process context.
1053 int usb_resume_both(struct usb_device
*udev
)
1057 struct usb_interface
*intf
;
1058 struct usb_device
*parent
= udev
->parent
;
1060 cancel_delayed_work(&udev
->autosuspend
);
1061 if (udev
->state
== USB_STATE_NOTATTACHED
)
1064 /* Propagate the resume up the tree, if necessary */
1065 if (udev
->state
== USB_STATE_SUSPENDED
) {
1067 usb_pm_lock(parent
);
1068 parent
->auto_pm
= 1;
1069 status
= usb_resume_both(parent
);
1072 /* We can't progagate beyond the USB subsystem,
1073 * so if a root hub's controller is suspended
1074 * then we're stuck. */
1075 if (udev
->dev
.parent
->power
.power_state
.event
!=
1077 status
= -EHOSTUNREACH
;
1080 status
= resume_device(udev
);
1082 usb_pm_unlock(parent
);
1085 /* Needed only for setting udev->dev.power.power_state.event
1086 * and for possible debugging message. */
1087 status
= resume_device(udev
);
1090 /* Now the parent won't suspend until we are finished */
1092 if (status
== 0 && udev
->actconfig
) {
1093 for (i
= 0; i
< udev
->actconfig
->desc
.bNumInterfaces
; i
++) {
1094 intf
= udev
->actconfig
->interface
[i
];
1095 resume_interface(intf
);
1099 // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
1103 #ifdef CONFIG_USB_SUSPEND
1106 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1107 * @udev: the usb_device to autosuspend
1108 * @dec_usage_cnt: flag to decrement @udev's PM-usage counter
1110 * This routine should be called when a core subsystem is finished using
1111 * @udev and wants to allow it to autosuspend. Examples would be when
1112 * @udev's device file in usbfs is closed or after a configuration change.
1114 * @dec_usage_cnt should be 1 if the subsystem previously incremented
1115 * @udev's usage counter (such as by passing 1 to usb_autoresume_device);
1116 * otherwise it should be 0.
1118 * If the usage counter for @udev or any of its active interfaces is greater
1119 * than 0, the autosuspend request will not be queued. (If an interface
1120 * driver does not support autosuspend then its usage counter is permanently
1121 * positive.) Likewise, if an interface driver requires remote-wakeup
1122 * capability during autosuspend but remote wakeup is disabled, the
1123 * autosuspend will fail.
1125 * Often the caller will hold @udev's device lock, but this is not
1128 * This routine can run only in process context.
1130 void usb_autosuspend_device(struct usb_device
*udev
, int dec_usage_cnt
)
1133 udev
->pm_usage_cnt
-= dec_usage_cnt
;
1134 if (udev
->pm_usage_cnt
<= 0)
1135 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1136 USB_AUTOSUSPEND_DELAY
);
1137 usb_pm_unlock(udev
);
1138 // dev_dbg(&udev->dev, "%s: cnt %d\n",
1139 // __FUNCTION__, udev->pm_usage_cnt);
1143 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1144 * @udev: the usb_device to autoresume
1145 * @inc_usage_cnt: flag to increment @udev's PM-usage counter
1147 * This routine should be called when a core subsystem wants to use @udev
1148 * and needs to guarantee that it is not suspended. In addition, the
1149 * caller can prevent @udev from being autosuspended subsequently. (Note
1150 * that this will not prevent suspend events originating in the PM core.)
1151 * Examples would be when @udev's device file in usbfs is opened (autosuspend
1152 * should be prevented until the file is closed) or when a remote-wakeup
1153 * request is received (later autosuspends should not be prevented).
1155 * @inc_usage_cnt should be 1 to increment @udev's usage counter and prevent
1156 * autosuspends. This prevention will persist until the usage counter is
1157 * decremented again (such as by passing 1 to usb_autosuspend_device).
1158 * Otherwise @inc_usage_cnt should be 0 to leave the usage counter unchanged.
1159 * Regardless, if the autoresume fails then the usage counter is not
1162 * Often the caller will hold @udev's device lock, but this is not
1163 * necessary (and attempting it might cause deadlock).
1165 * This routine can run only in process context.
1167 int usb_autoresume_device(struct usb_device
*udev
, int inc_usage_cnt
)
1172 udev
->pm_usage_cnt
+= inc_usage_cnt
;
1174 status
= usb_resume_both(udev
);
1176 udev
->pm_usage_cnt
-= inc_usage_cnt
;
1177 usb_pm_unlock(udev
);
1178 // dev_dbg(&udev->dev, "%s: status %d cnt %d\n",
1179 // __FUNCTION__, status, udev->pm_usage_cnt);
1184 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1185 * @intf: the usb_interface whose counter should be decremented
1187 * This routine should be called by an interface driver when it is
1188 * finished using @intf and wants to allow it to autosuspend. A typical
1189 * example would be a character-device driver when its device file is
1192 * The routine decrements @intf's usage counter. When the counter reaches
1193 * 0, a delayed autosuspend request for @intf's device is queued. When
1194 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1195 * the other usage counters for the sibling interfaces and @intf's
1196 * usb_device, the device and all its interfaces will be autosuspended.
1198 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1199 * core will not change its value other than the increment and decrement
1200 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1201 * may use this simple counter-oriented discipline or may set the value
1204 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1205 * take place only if the device's remote-wakeup facility is enabled.
1207 * Suspend method calls queued by this routine can arrive at any time
1208 * while @intf is resumed and its usage counter is equal to 0. They are
1209 * not protected by the usb_device's lock but only by its pm_mutex.
1210 * Drivers must provide their own synchronization.
1212 * This routine can run only in process context.
1214 void usb_autopm_put_interface(struct usb_interface
*intf
)
1216 struct usb_device
*udev
= interface_to_usbdev(intf
);
1219 if (intf
->condition
!= USB_INTERFACE_UNBOUND
&&
1220 --intf
->pm_usage_cnt
<= 0) {
1221 queue_delayed_work(ksuspend_usb_wq
, &udev
->autosuspend
,
1222 USB_AUTOSUSPEND_DELAY
);
1224 usb_pm_unlock(udev
);
1225 // dev_dbg(&intf->dev, "%s: cnt %d\n",
1226 // __FUNCTION__, intf->pm_usage_cnt);
1228 EXPORT_SYMBOL_GPL(usb_autopm_put_interface
);
1231 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1232 * @intf: the usb_interface whose counter should be incremented
1234 * This routine should be called by an interface driver when it wants to
1235 * use @intf and needs to guarantee that it is not suspended. In addition,
1236 * the routine prevents @intf from being autosuspended subsequently. (Note
1237 * that this will not prevent suspend events originating in the PM core.)
1238 * This prevention will persist until usb_autopm_put_interface() is called
1239 * or @intf is unbound. A typical example would be a character-device
1240 * driver when its device file is opened.
1242 * The routine increments @intf's usage counter. So long as the counter
1243 * is greater than 0, autosuspend will not be allowed for @intf or its
1244 * usb_device. When the driver is finished using @intf it should call
1245 * usb_autopm_put_interface() to decrement the usage counter and queue
1246 * a delayed autosuspend request (if the counter is <= 0).
1248 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1249 * core will not change its value other than the increment and decrement
1250 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1251 * may use this simple counter-oriented discipline or may set the value
1254 * Resume method calls generated by this routine can arrive at any time
1255 * while @intf is suspended. They are not protected by the usb_device's
1256 * lock but only by its pm_mutex. Drivers must provide their own
1259 * This routine can run only in process context.
1261 int usb_autopm_get_interface(struct usb_interface
*intf
)
1263 struct usb_device
*udev
= interface_to_usbdev(intf
);
1267 if (intf
->condition
== USB_INTERFACE_UNBOUND
)
1270 ++intf
->pm_usage_cnt
;
1272 status
= usb_resume_both(udev
);
1274 --intf
->pm_usage_cnt
;
1276 usb_pm_unlock(udev
);
1277 // dev_dbg(&intf->dev, "%s: status %d cnt %d\n",
1278 // __FUNCTION__, status, intf->pm_usage_cnt);
1281 EXPORT_SYMBOL_GPL(usb_autopm_get_interface
);
1283 #endif /* CONFIG_USB_SUSPEND */
1285 static int usb_suspend(struct device
*dev
, pm_message_t message
)
1289 if (is_usb_device(dev
)) {
1290 struct usb_device
*udev
= to_usb_device(dev
);
1294 status
= usb_suspend_both(udev
, message
);
1295 usb_pm_unlock(udev
);
1301 static int usb_resume(struct device
*dev
)
1305 if (is_usb_device(dev
)) {
1306 struct usb_device
*udev
= to_usb_device(dev
);
1310 status
= usb_resume_both(udev
);
1311 usb_pm_unlock(udev
);
1313 /* Rebind drivers that had no suspend method? */
1319 #endif /* CONFIG_PM */
1321 struct bus_type usb_bus_type
= {
1323 .match
= usb_device_match
,
1324 .uevent
= usb_uevent
,
1326 .suspend
= usb_suspend
,
1327 .resume
= usb_resume
,