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 = sysfs_create_file(&usb_drv->drvwrap.driver.kobj,
95 &driver_attr_new_id.attr);
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 sysfs_remove_file(&usb_drv->drvwrap.driver.kobj,
107 &driver_attr_new_id.attr);
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", __FUNCTION__);
162 if (!is_usb_device(dev)) /* Sanity check */
165 udev = to_usb_device(dev);
167 /* TODO: Add real matching code */
169 /* The device should always appear to be in use
170 * unless the driver suports autosuspend.
172 udev->pm_usage_cnt = !(udriver->supports_autosuspend);
174 error = udriver->probe(udev);
178 /* called from driver core with dev locked */
179 static int usb_unbind_device(struct device *dev)
181 struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
183 udriver->disconnect(to_usb_device(dev));
188 /* called from driver core with dev locked */
189 static int usb_probe_interface(struct device *dev)
191 struct usb_driver *driver = to_usb_driver(dev->driver);
192 struct usb_interface *intf;
193 struct usb_device *udev;
194 const struct usb_device_id *id;
197 dev_dbg(dev, "%s\n", __FUNCTION__);
199 if (is_usb_device(dev)) /* Sanity check */
202 intf = to_usb_interface(dev);
203 udev = interface_to_usbdev(intf);
205 id = usb_match_id(intf, driver->id_table);
207 id = usb_match_dynamic_id(intf, driver);
209 dev_dbg(dev, "%s - got id\n", __FUNCTION__);
211 error = usb_autoresume_device(udev);
215 /* Interface "power state" doesn't correspond to any hardware
216 * state whatsoever. We use it to record when it's bound to
217 * a driver that may start I/0: it's not frozen/quiesced.
220 intf->condition = USB_INTERFACE_BINDING;
222 /* The interface should always appear to be in use
223 * unless the driver suports autosuspend.
225 intf->pm_usage_cnt = !(driver->supports_autosuspend);
227 error = driver->probe(intf, id);
230 intf->needs_remote_wakeup = 0;
231 intf->condition = USB_INTERFACE_UNBOUND;
233 intf->condition = USB_INTERFACE_BOUND;
235 usb_autosuspend_device(udev);
241 /* called from driver core with dev locked */
242 static int usb_unbind_interface(struct device *dev)
244 struct usb_driver *driver = to_usb_driver(dev->driver);
245 struct usb_interface *intf = to_usb_interface(dev);
246 struct usb_device *udev;
249 intf->condition = USB_INTERFACE_UNBINDING;
251 /* Autoresume for set_interface call below */
252 udev = interface_to_usbdev(intf);
253 error = usb_autoresume_device(udev);
255 /* release all urbs for this interface */
256 usb_disable_interface(interface_to_usbdev(intf), intf);
258 driver->disconnect(intf);
260 /* reset other interface state */
261 usb_set_interface(interface_to_usbdev(intf),
262 intf->altsetting[0].desc.bInterfaceNumber,
264 usb_set_intfdata(intf, NULL);
266 intf->condition = USB_INTERFACE_UNBOUND;
268 intf->needs_remote_wakeup = 0;
271 usb_autosuspend_device(udev);
277 * usb_driver_claim_interface - bind a driver to an interface
278 * @driver: the driver to be bound
279 * @iface: the interface to which it will be bound; must be in the
280 * usb device's active configuration
281 * @priv: driver data associated with that interface
283 * This is used by usb device drivers that need to claim more than one
284 * interface on a device when probing (audio and acm are current examples).
285 * No device driver should directly modify internal usb_interface or
286 * usb_device structure members.
288 * Few drivers should need to use this routine, since the most natural
289 * way to bind to an interface is to return the private data from
290 * the driver's probe() method.
292 * Callers must own the device lock, so driver probe() entries don't need
293 * extra locking, but other call contexts may need to explicitly claim that
296 int usb_driver_claim_interface(struct usb_driver *driver,
297 struct usb_interface *iface, void* priv)
299 struct device *dev = &iface->dev;
300 struct usb_device *udev = interface_to_usbdev(iface);
306 dev->driver = &driver->drvwrap.driver;
307 usb_set_intfdata(iface, priv);
310 iface->condition = USB_INTERFACE_BOUND;
312 iface->pm_usage_cnt = !(driver->supports_autosuspend);
315 /* if interface was already added, bind now; else let
316 * the future device_add() bind it, bypassing probe()
318 if (device_is_registered(dev))
319 retval = device_bind_driver(dev);
323 EXPORT_SYMBOL(usb_driver_claim_interface);
326 * usb_driver_release_interface - unbind a driver from an interface
327 * @driver: the driver to be unbound
328 * @iface: the interface from which it will be unbound
330 * This can be used by drivers to release an interface without waiting
331 * for their disconnect() methods to be called. In typical cases this
332 * also causes the driver disconnect() method to be called.
334 * This call is synchronous, and may not be used in an interrupt context.
335 * Callers must own the device lock, so driver disconnect() entries don't
336 * need extra locking, but other call contexts may need to explicitly claim
339 void usb_driver_release_interface(struct usb_driver *driver,
340 struct usb_interface *iface)
342 struct device *dev = &iface->dev;
343 struct usb_device *udev = interface_to_usbdev(iface);
345 /* this should never happen, don't release something that's not ours */
346 if (!dev->driver || dev->driver != &driver->drvwrap.driver)
349 /* don't release from within disconnect() */
350 if (iface->condition != USB_INTERFACE_BOUND)
353 /* don't release if the interface hasn't been added yet */
354 if (device_is_registered(dev)) {
355 iface->condition = USB_INTERFACE_UNBINDING;
356 device_release_driver(dev);
360 usb_set_intfdata(iface, NULL);
363 iface->condition = USB_INTERFACE_UNBOUND;
364 mark_quiesced(iface);
365 iface->needs_remote_wakeup = 0;
368 EXPORT_SYMBOL(usb_driver_release_interface);
370 /* returns 0 if no match, 1 if match */
371 int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
373 if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
374 id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
377 if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
378 id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
381 /* No need to test id->bcdDevice_lo != 0, since 0 is never
382 greater than any unsigned number. */
383 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
384 (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
387 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
388 (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
391 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
392 (id->bDeviceClass != dev->descriptor.bDeviceClass))
395 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
396 (id->bDeviceSubClass!= dev->descriptor.bDeviceSubClass))
399 if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
400 (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
406 /* returns 0 if no match, 1 if match */
407 int usb_match_one_id(struct usb_interface *interface,
408 const struct usb_device_id *id)
410 struct usb_host_interface *intf;
411 struct usb_device *dev;
413 /* proc_connectinfo in devio.c may call us with id == NULL. */
417 intf = interface->cur_altsetting;
418 dev = interface_to_usbdev(interface);
420 if (!usb_match_device(dev, id))
423 /* The interface class, subclass, and protocol should never be
424 * checked for a match if the device class is Vendor Specific,
425 * unless the match record specifies the Vendor ID. */
426 if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
427 !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
428 (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
429 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
430 USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
433 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
434 (id->bInterfaceClass != intf->desc.bInterfaceClass))
437 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
438 (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
441 if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
442 (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
447 EXPORT_SYMBOL_GPL(usb_match_one_id);
450 * usb_match_id - find first usb_device_id matching device or interface
451 * @interface: the interface of interest
452 * @id: array of usb_device_id structures, terminated by zero entry
454 * usb_match_id searches an array of usb_device_id's and returns
455 * the first one matching the device or interface, or null.
456 * This is used when binding (or rebinding) a driver to an interface.
457 * Most USB device drivers will use this indirectly, through the usb core,
458 * but some layered driver frameworks use it directly.
459 * These device tables are exported with MODULE_DEVICE_TABLE, through
460 * modutils, to support the driver loading functionality of USB hotplugging.
464 * The "match_flags" element in a usb_device_id controls which
465 * members are used. If the corresponding bit is set, the
466 * value in the device_id must match its corresponding member
467 * in the device or interface descriptor, or else the device_id
470 * "driver_info" is normally used only by device drivers,
471 * but you can create a wildcard "matches anything" usb_device_id
472 * as a driver's "modules.usbmap" entry if you provide an id with
473 * only a nonzero "driver_info" field. If you do this, the USB device
474 * driver's probe() routine should use additional intelligence to
475 * decide whether to bind to the specified interface.
477 * What Makes Good usb_device_id Tables:
479 * The match algorithm is very simple, so that intelligence in
480 * driver selection must come from smart driver id records.
481 * Unless you have good reasons to use another selection policy,
482 * provide match elements only in related groups, and order match
483 * specifiers from specific to general. Use the macros provided
484 * for that purpose if you can.
486 * The most specific match specifiers use device descriptor
487 * data. These are commonly used with product-specific matches;
488 * the USB_DEVICE macro lets you provide vendor and product IDs,
489 * and you can also match against ranges of product revisions.
490 * These are widely used for devices with application or vendor
491 * specific bDeviceClass values.
493 * Matches based on device class/subclass/protocol specifications
494 * are slightly more general; use the USB_DEVICE_INFO macro, or
495 * its siblings. These are used with single-function devices
496 * where bDeviceClass doesn't specify that each interface has
499 * Matches based on interface class/subclass/protocol are the
500 * most general; they let drivers bind to any interface on a
501 * multiple-function device. Use the USB_INTERFACE_INFO
502 * macro, or its siblings, to match class-per-interface style
503 * devices (as recorded in bInterfaceClass).
505 * Note that an entry created by USB_INTERFACE_INFO won't match
506 * any interface if the device class is set to Vendor-Specific.
507 * This is deliberate; according to the USB spec the meanings of
508 * the interface class/subclass/protocol for these devices are also
509 * vendor-specific, and hence matching against a standard product
510 * class wouldn't work anyway. If you really want to use an
511 * interface-based match for such a device, create a match record
512 * that also specifies the vendor ID. (Unforunately there isn't a
513 * standard macro for creating records like this.)
515 * Within those groups, remember that not all combinations are
516 * meaningful. For example, don't give a product version range
517 * without vendor and product IDs; or specify a protocol without
518 * its associated class and subclass.
520 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
521 const struct usb_device_id *id)
523 /* proc_connectinfo in devio.c may call us with id == NULL. */
527 /* It is important to check that id->driver_info is nonzero,
528 since an entry that is all zeroes except for a nonzero
529 id->driver_info is the way to create an entry that
530 indicates that the driver want to examine every
531 device and interface. */
532 for (; id->idVendor || id->bDeviceClass || id->bInterfaceClass ||
533 id->driver_info; id++) {
534 if (usb_match_one_id(interface, id))
540 EXPORT_SYMBOL_GPL_FUTURE(usb_match_id);
542 static int usb_device_match(struct device *dev, struct device_driver *drv)
544 /* devices and interfaces are handled separately */
545 if (is_usb_device(dev)) {
547 /* interface drivers never match devices */
548 if (!is_usb_device_driver(drv))
551 /* TODO: Add real matching code */
555 struct usb_interface *intf;
556 struct usb_driver *usb_drv;
557 const struct usb_device_id *id;
559 /* device drivers never match interfaces */
560 if (is_usb_device_driver(drv))
563 intf = to_usb_interface(dev);
564 usb_drv = to_usb_driver(drv);
566 id = usb_match_id(intf, usb_drv->id_table);
570 id = usb_match_dynamic_id(intf, usb_drv);
578 #ifdef CONFIG_HOTPLUG
579 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
581 struct usb_device *usb_dev;
586 /* driver is often null here; dev_dbg() would oops */
587 pr_debug ("usb %s: uevent\n", dev->bus_id);
589 if (is_usb_device(dev))
590 usb_dev = to_usb_device(dev);
592 struct usb_interface *intf = to_usb_interface(dev);
593 usb_dev = interface_to_usbdev(intf);
596 if (usb_dev->devnum < 0) {
597 pr_debug ("usb %s: already deleted?\n", dev->bus_id);
601 pr_debug ("usb %s: bus removed?\n", dev->bus_id);
605 #ifdef CONFIG_USB_DEVICEFS
606 /* If this is available, userspace programs can directly read
607 * all the device descriptors we don't tell them about. Or
608 * act as usermode drivers.
610 if (add_uevent_var(env, "DEVICE=/proc/bus/usb/%03d/%03d",
611 usb_dev->bus->busnum, usb_dev->devnum))
615 /* per-device configurations are common */
616 if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
617 le16_to_cpu(usb_dev->descriptor.idVendor),
618 le16_to_cpu(usb_dev->descriptor.idProduct),
619 le16_to_cpu(usb_dev->descriptor.bcdDevice)))
622 /* class-based driver binding models */
623 if (add_uevent_var(env, "TYPE=%d/%d/%d",
624 usb_dev->descriptor.bDeviceClass,
625 usb_dev->descriptor.bDeviceSubClass,
626 usb_dev->descriptor.bDeviceProtocol))
629 if (add_uevent_var(env, "BUSNUM=%03d",
630 usb_dev->bus->busnum))
633 if (add_uevent_var(env, "DEVNUM=%03d",
642 static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
646 #endif /* CONFIG_HOTPLUG */
649 * usb_register_device_driver - register a USB device (not interface) driver
650 * @new_udriver: USB operations for the device driver
651 * @owner: module owner of this driver.
653 * Registers a USB device driver with the USB core. The list of
654 * unattached devices will be rescanned whenever a new driver is
655 * added, allowing the new driver to attach to any recognized devices.
656 * Returns a negative error code on failure and 0 on success.
658 int usb_register_device_driver(struct usb_device_driver *new_udriver,
659 struct module *owner)
666 new_udriver->drvwrap.for_devices = 1;
667 new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
668 new_udriver->drvwrap.driver.bus = &usb_bus_type;
669 new_udriver->drvwrap.driver.probe = usb_probe_device;
670 new_udriver->drvwrap.driver.remove = usb_unbind_device;
671 new_udriver->drvwrap.driver.owner = owner;
673 retval = driver_register(&new_udriver->drvwrap.driver);
676 pr_info("%s: registered new device driver %s\n",
677 usbcore_name, new_udriver->name);
678 usbfs_update_special();
680 printk(KERN_ERR "%s: error %d registering device "
682 usbcore_name, retval, new_udriver->name);
687 EXPORT_SYMBOL_GPL(usb_register_device_driver);
690 * usb_deregister_device_driver - unregister a USB device (not interface) driver
691 * @udriver: USB operations of the device driver to unregister
692 * Context: must be able to sleep
694 * Unlinks the specified driver from the internal USB driver list.
696 void usb_deregister_device_driver(struct usb_device_driver *udriver)
698 pr_info("%s: deregistering device driver %s\n",
699 usbcore_name, udriver->name);
701 driver_unregister(&udriver->drvwrap.driver);
702 usbfs_update_special();
704 EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
707 * usb_register_driver - register a USB interface driver
708 * @new_driver: USB operations for the interface driver
709 * @owner: module owner of this driver.
710 * @mod_name: module name string
712 * Registers a USB interface driver with the USB core. The list of
713 * unattached interfaces will be rescanned whenever a new driver is
714 * added, allowing the new driver to attach to any recognized interfaces.
715 * Returns a negative error code on failure and 0 on success.
717 * NOTE: if you want your driver to use the USB major number, you must call
718 * usb_register_dev() to enable that functionality. This function no longer
719 * takes care of that.
721 int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
722 const char *mod_name)
729 new_driver->drvwrap.for_devices = 0;
730 new_driver->drvwrap.driver.name = (char *) new_driver->name;
731 new_driver->drvwrap.driver.bus = &usb_bus_type;
732 new_driver->drvwrap.driver.probe = usb_probe_interface;
733 new_driver->drvwrap.driver.remove = usb_unbind_interface;
734 new_driver->drvwrap.driver.owner = owner;
735 new_driver->drvwrap.driver.mod_name = mod_name;
736 spin_lock_init(&new_driver->dynids.lock);
737 INIT_LIST_HEAD(&new_driver->dynids.list);
739 retval = driver_register(&new_driver->drvwrap.driver);
742 pr_info("%s: registered new interface driver %s\n",
743 usbcore_name, new_driver->name);
744 usbfs_update_special();
745 usb_create_newid_file(new_driver);
747 printk(KERN_ERR "%s: error %d registering interface "
749 usbcore_name, retval, new_driver->name);
754 EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver);
757 * usb_deregister - unregister a USB interface driver
758 * @driver: USB operations of the interface driver to unregister
759 * Context: must be able to sleep
761 * Unlinks the specified driver from the internal USB driver list.
763 * NOTE: If you called usb_register_dev(), you still need to call
764 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
765 * this * call will no longer do it for you.
767 void usb_deregister(struct usb_driver *driver)
769 pr_info("%s: deregistering interface driver %s\n",
770 usbcore_name, driver->name);
772 usb_remove_newid_file(driver);
773 usb_free_dynids(driver);
774 driver_unregister(&driver->drvwrap.driver);
776 usbfs_update_special();
778 EXPORT_SYMBOL_GPL_FUTURE(usb_deregister);
782 /* Caller has locked udev's pm_mutex */
783 static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
785 struct usb_device_driver *udriver;
788 if (udev->state == USB_STATE_NOTATTACHED ||
789 udev->state == USB_STATE_SUSPENDED)
792 /* For devices that don't have a driver, we do a generic suspend. */
793 if (udev->dev.driver)
794 udriver = to_usb_device_driver(udev->dev.driver);
796 udev->do_remote_wakeup = 0;
797 udriver = &usb_generic_driver;
799 status = udriver->suspend(udev, msg);
802 dev_vdbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
804 udev->dev.power.power_state.event = msg.event;
808 /* Caller has locked udev's pm_mutex */
809 static int usb_resume_device(struct usb_device *udev)
811 struct usb_device_driver *udriver;
814 if (udev->state == USB_STATE_NOTATTACHED)
816 if (udev->state != USB_STATE_SUSPENDED && !udev->reset_resume)
819 /* Can't resume it if it doesn't have a driver. */
820 if (udev->dev.driver == NULL) {
825 if (udev->quirks & USB_QUIRK_RESET_RESUME)
826 udev->reset_resume = 1;
828 udriver = to_usb_device_driver(udev->dev.driver);
829 status = udriver->resume(udev);
832 dev_vdbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
834 udev->autoresume_disabled = 0;
835 udev->dev.power.power_state.event = PM_EVENT_ON;
840 /* Caller has locked intf's usb_device's pm mutex */
841 static int usb_suspend_interface(struct usb_interface *intf, pm_message_t msg)
843 struct usb_driver *driver;
846 /* with no hardware, USB interfaces only use FREEZE and ON states */
847 if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
851 if (intf->condition == USB_INTERFACE_UNBOUND) /* This can't happen */
853 driver = to_usb_driver(intf->dev.driver);
855 if (driver->suspend && driver->resume) {
856 status = driver->suspend(intf, msg);
859 else if (!interface_to_usbdev(intf)->auto_pm)
860 dev_err(&intf->dev, "%s error %d\n",
863 // FIXME else if there's no suspend method, disconnect...
864 // Not possible if auto_pm is set...
865 dev_warn(&intf->dev, "no suspend for driver %s?\n",
871 dev_vdbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
875 /* Caller has locked intf's usb_device's pm_mutex */
876 static int usb_resume_interface(struct usb_interface *intf, int reset_resume)
878 struct usb_driver *driver;
881 if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
885 /* Don't let autoresume interfere with unbinding */
886 if (intf->condition == USB_INTERFACE_UNBINDING)
889 /* Can't resume it if it doesn't have a driver. */
890 if (intf->condition == USB_INTERFACE_UNBOUND) {
894 driver = to_usb_driver(intf->dev.driver);
897 if (driver->reset_resume) {
898 status = driver->reset_resume(intf);
900 dev_err(&intf->dev, "%s error %d\n",
901 "reset_resume", status);
903 // status = -EOPNOTSUPP;
904 dev_warn(&intf->dev, "no %s for driver %s?\n",
905 "reset_resume", driver->name);
908 if (driver->resume) {
909 status = driver->resume(intf);
911 dev_err(&intf->dev, "%s error %d\n",
914 // status = -EOPNOTSUPP;
915 dev_warn(&intf->dev, "no %s for driver %s?\n",
916 "resume", driver->name);
921 dev_vdbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
925 /* FIXME: Unbind the driver and reprobe if the resume failed
926 * (not possible if auto_pm is set) */
930 #ifdef CONFIG_USB_SUSPEND
932 /* Internal routine to check whether we may autosuspend a device. */
933 static int autosuspend_check(struct usb_device *udev)
936 struct usb_interface *intf;
937 unsigned long suspend_time;
939 /* For autosuspend, fail fast if anything is in use or autosuspend
940 * is disabled. Also fail if any interfaces require remote wakeup
941 * but it isn't available.
943 udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
944 if (udev->pm_usage_cnt > 0)
946 if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled)
949 suspend_time = udev->last_busy + udev->autosuspend_delay;
950 if (udev->actconfig) {
951 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
952 intf = udev->actconfig->interface[i];
953 if (!is_active(intf))
955 if (intf->pm_usage_cnt > 0)
957 if (intf->needs_remote_wakeup &&
958 !udev->do_remote_wakeup) {
959 dev_dbg(&udev->dev, "remote wakeup needed "
960 "for autosuspend\n");
964 /* Don't allow autosuspend if the device will need
965 * a reset-resume and any of its interface drivers
966 * doesn't include support.
968 if (udev->quirks & USB_QUIRK_RESET_RESUME) {
969 struct usb_driver *driver;
971 driver = to_usb_driver(intf->dev.driver);
972 if (!driver->reset_resume)
978 /* If everything is okay but the device hasn't been idle for long
979 * enough, queue a delayed autosuspend request.
981 if (time_after(suspend_time, jiffies)) {
982 if (!timer_pending(&udev->autosuspend.timer)) {
984 /* The value of jiffies may change between the
985 * time_after() comparison above and the subtraction
986 * below. That's okay; the system behaves sanely
987 * when a timer is registered for the present moment
990 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
991 round_jiffies_relative(suspend_time - jiffies));
1000 static inline int autosuspend_check(struct usb_device *udev)
1005 #endif /* CONFIG_USB_SUSPEND */
1008 * usb_suspend_both - suspend a USB device and its interfaces
1009 * @udev: the usb_device to suspend
1010 * @msg: Power Management message describing this state transition
1012 * This is the central routine for suspending USB devices. It calls the
1013 * suspend methods for all the interface drivers in @udev and then calls
1014 * the suspend method for @udev itself. If an error occurs at any stage,
1015 * all the interfaces which were suspended are resumed so that they remain
1016 * in the same state as the device.
1018 * If an autosuspend is in progress (@udev->auto_pm is set), the routine
1019 * checks first to make sure that neither the device itself or any of its
1020 * active interfaces is in use (pm_usage_cnt is greater than 0). If they
1021 * are, the autosuspend fails.
1023 * If the suspend succeeds, the routine recursively queues an autosuspend
1024 * request for @udev's parent device, thereby propagating the change up
1025 * the device tree. If all of the parent's children are now suspended,
1026 * the parent will autosuspend in turn.
1028 * The suspend method calls are subject to mutual exclusion under control
1029 * of @udev's pm_mutex. Many of these calls are also under the protection
1030 * of @udev's device lock (including all requests originating outside the
1031 * USB subsystem), but autosuspend requests generated by a child device or
1032 * interface driver may not be. Usbcore will insure that the method calls
1033 * do not arrive during bind, unbind, or reset operations. However, drivers
1034 * must be prepared to handle suspend calls arriving at unpredictable times.
1035 * The only way to block such calls is to do an autoresume (preventing
1036 * autosuspends) while holding @udev's device lock (preventing outside
1039 * The caller must hold @udev->pm_mutex.
1041 * This routine can run only in process context.
1043 static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1047 struct usb_interface *intf;
1048 struct usb_device *parent = udev->parent;
1050 if (udev->state == USB_STATE_NOTATTACHED ||
1051 udev->state == USB_STATE_SUSPENDED)
1054 udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
1056 if (udev->auto_pm) {
1057 status = autosuspend_check(udev);
1062 /* Suspend all the interfaces and then udev itself */
1063 if (udev->actconfig) {
1064 for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
1065 intf = udev->actconfig->interface[i];
1066 status = usb_suspend_interface(intf, msg);
1073 /* Non-root devices don't need to do anything for FREEZE
1075 if (udev->parent && (msg.event == PM_EVENT_FREEZE ||
1076 msg.event == PM_EVENT_PRETHAW))
1078 status = usb_suspend_device(udev, msg);
1081 /* If the suspend failed, resume interfaces that did get suspended */
1084 intf = udev->actconfig->interface[i];
1085 usb_resume_interface(intf, 0);
1088 /* Try another autosuspend when the interfaces aren't busy */
1090 autosuspend_check(udev);
1092 /* If the suspend succeeded, propagate it up the tree */
1094 cancel_delayed_work(&udev->autosuspend);
1096 usb_autosuspend_device(parent);
1100 dev_vdbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
1105 * usb_resume_both - resume a USB device and its interfaces
1106 * @udev: the usb_device to resume
1108 * This is the central routine for resuming USB devices. It calls the
1109 * the resume method for @udev and then calls the resume methods for all
1110 * the interface drivers in @udev.
1112 * Before starting the resume, the routine calls itself recursively for
1113 * the parent device of @udev, thereby propagating the change up the device
1114 * tree and assuring that @udev will be able to resume. If the parent is
1115 * unable to resume successfully, the routine fails.
1117 * The resume method calls are subject to mutual exclusion under control
1118 * of @udev's pm_mutex. Many of these calls are also under the protection
1119 * of @udev's device lock (including all requests originating outside the
1120 * USB subsystem), but autoresume requests generated by a child device or
1121 * interface driver may not be. Usbcore will insure that the method calls
1122 * do not arrive during bind, unbind, or reset operations. However, drivers
1123 * must be prepared to handle resume calls arriving at unpredictable times.
1124 * The only way to block such calls is to do an autoresume (preventing
1125 * other autoresumes) while holding @udev's device lock (preventing outside
1128 * The caller must hold @udev->pm_mutex.
1130 * This routine can run only in process context.
1132 static int usb_resume_both(struct usb_device *udev)
1136 struct usb_interface *intf;
1137 struct usb_device *parent = udev->parent;
1139 cancel_delayed_work(&udev->autosuspend);
1140 if (udev->state == USB_STATE_NOTATTACHED) {
1145 /* Propagate the resume up the tree, if necessary */
1146 if (udev->state == USB_STATE_SUSPENDED) {
1147 if (udev->auto_pm && udev->autoresume_disabled) {
1152 status = usb_autoresume_device(parent);
1154 status = usb_resume_device(udev);
1155 if (status || udev->state ==
1156 USB_STATE_NOTATTACHED) {
1157 usb_autosuspend_device(parent);
1159 /* It's possible usb_resume_device()
1160 * failed after the port was
1161 * unsuspended, causing udev to be
1162 * logically disconnected. We don't
1163 * want usb_disconnect() to autosuspend
1164 * the parent again, so tell it that
1165 * udev disconnected while still
1168 USB_STATE_NOTATTACHED)
1169 udev->discon_suspended = 1;
1174 /* We can't progagate beyond the USB subsystem,
1175 * so if a root hub's controller is suspended
1176 * then we're stuck. */
1177 status = usb_resume_device(udev);
1181 /* Needed for setting udev->dev.power.power_state.event,
1182 * for possible debugging message, and for reset_resume. */
1183 status = usb_resume_device(udev);
1186 if (status == 0 && udev->actconfig) {
1187 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1188 intf = udev->actconfig->interface[i];
1189 usb_resume_interface(intf, udev->reset_resume);
1194 dev_vdbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
1195 udev->reset_resume = 0;
1199 #ifdef CONFIG_USB_SUSPEND
1201 /* Internal routine to adjust a device's usage counter and change
1202 * its autosuspend state.
1204 static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
1210 udev->pm_usage_cnt += inc_usage_cnt;
1211 WARN_ON(udev->pm_usage_cnt < 0);
1213 udev->last_busy = jiffies;
1214 if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
1215 if (udev->state == USB_STATE_SUSPENDED)
1216 status = usb_resume_both(udev);
1218 udev->pm_usage_cnt -= inc_usage_cnt;
1219 else if (inc_usage_cnt)
1220 udev->last_busy = jiffies;
1221 } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
1222 status = usb_suspend_both(udev, PMSG_SUSPEND);
1224 usb_pm_unlock(udev);
1228 /* usb_autosuspend_work - callback routine to autosuspend a USB device */
1229 void usb_autosuspend_work(struct work_struct *work)
1231 struct usb_device *udev =
1232 container_of(work, struct usb_device, autosuspend.work);
1234 usb_autopm_do_device(udev, 0);
1238 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1239 * @udev: the usb_device to autosuspend
1241 * This routine should be called when a core subsystem is finished using
1242 * @udev and wants to allow it to autosuspend. Examples would be when
1243 * @udev's device file in usbfs is closed or after a configuration change.
1245 * @udev's usage counter is decremented. If it or any of the usage counters
1246 * for an active interface is greater than 0, no autosuspend request will be
1247 * queued. (If an interface driver does not support autosuspend then its
1248 * usage counter is permanently positive.) Furthermore, if an interface
1249 * driver requires remote-wakeup capability during autosuspend but remote
1250 * wakeup is disabled, the autosuspend will fail.
1252 * Often the caller will hold @udev's device lock, but this is not
1255 * This routine can run only in process context.
1257 void usb_autosuspend_device(struct usb_device *udev)
1261 status = usb_autopm_do_device(udev, -1);
1262 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1263 __FUNCTION__, udev->pm_usage_cnt);
1267 * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces
1268 * @udev: the usb_device to autosuspend
1270 * This routine should be called when a core subsystem thinks @udev may
1271 * be ready to autosuspend.
1273 * @udev's usage counter left unchanged. If it or any of the usage counters
1274 * for an active interface is greater than 0, or autosuspend is not allowed
1275 * for any other reason, no autosuspend request will be queued.
1277 * This routine can run only in process context.
1279 void usb_try_autosuspend_device(struct usb_device *udev)
1281 usb_autopm_do_device(udev, 0);
1282 dev_vdbg(&udev->dev, "%s: cnt %d\n",
1283 __FUNCTION__, udev->pm_usage_cnt);
1287 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1288 * @udev: the usb_device to autoresume
1290 * This routine should be called when a core subsystem wants to use @udev
1291 * and needs to guarantee that it is not suspended. No autosuspend will
1292 * occur until usb_autosuspend_device is called. (Note that this will not
1293 * prevent suspend events originating in the PM core.) Examples would be
1294 * when @udev's device file in usbfs is opened or when a remote-wakeup
1295 * request is received.
1297 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1298 * However if the autoresume fails then the usage counter is re-decremented.
1300 * Often the caller will hold @udev's device lock, but this is not
1301 * necessary (and attempting it might cause deadlock).
1303 * This routine can run only in process context.
1305 int usb_autoresume_device(struct usb_device *udev)
1309 status = usb_autopm_do_device(udev, 1);
1310 dev_vdbg(&udev->dev, "%s: status %d cnt %d\n",
1311 __FUNCTION__, status, udev->pm_usage_cnt);
1315 /* Internal routine to adjust an interface's usage counter and change
1316 * its device's autosuspend state.
1318 static int usb_autopm_do_interface(struct usb_interface *intf,
1321 struct usb_device *udev = interface_to_usbdev(intf);
1325 if (intf->condition == USB_INTERFACE_UNBOUND)
1329 intf->pm_usage_cnt += inc_usage_cnt;
1330 udev->last_busy = jiffies;
1331 if (inc_usage_cnt >= 0 && intf->pm_usage_cnt > 0) {
1332 if (udev->state == USB_STATE_SUSPENDED)
1333 status = usb_resume_both(udev);
1335 intf->pm_usage_cnt -= inc_usage_cnt;
1337 udev->last_busy = jiffies;
1338 } else if (inc_usage_cnt <= 0 && intf->pm_usage_cnt <= 0) {
1339 status = usb_suspend_both(udev, PMSG_SUSPEND);
1342 usb_pm_unlock(udev);
1347 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1348 * @intf: the usb_interface whose counter should be decremented
1350 * This routine should be called by an interface driver when it is
1351 * finished using @intf and wants to allow it to autosuspend. A typical
1352 * example would be a character-device driver when its device file is
1355 * The routine decrements @intf's usage counter. When the counter reaches
1356 * 0, a delayed autosuspend request for @intf's device is queued. When
1357 * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
1358 * the other usage counters for the sibling interfaces and @intf's
1359 * usb_device, the device and all its interfaces will be autosuspended.
1361 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1362 * core will not change its value other than the increment and decrement
1363 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1364 * may use this simple counter-oriented discipline or may set the value
1367 * If the driver has set @intf->needs_remote_wakeup then autosuspend will
1368 * take place only if the device's remote-wakeup facility is enabled.
1370 * Suspend method calls queued by this routine can arrive at any time
1371 * while @intf is resumed and its usage counter is equal to 0. They are
1372 * not protected by the usb_device's lock but only by its pm_mutex.
1373 * Drivers must provide their own synchronization.
1375 * This routine can run only in process context.
1377 void usb_autopm_put_interface(struct usb_interface *intf)
1381 status = usb_autopm_do_interface(intf, -1);
1382 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1383 __FUNCTION__, status, intf->pm_usage_cnt);
1385 EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1388 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1389 * @intf: the usb_interface whose counter should be incremented
1391 * This routine should be called by an interface driver when it wants to
1392 * use @intf and needs to guarantee that it is not suspended. In addition,
1393 * the routine prevents @intf from being autosuspended subsequently. (Note
1394 * that this will not prevent suspend events originating in the PM core.)
1395 * This prevention will persist until usb_autopm_put_interface() is called
1396 * or @intf is unbound. A typical example would be a character-device
1397 * driver when its device file is opened.
1400 * The routine increments @intf's usage counter. (However if the
1401 * autoresume fails then the counter is re-decremented.) So long as the
1402 * counter is greater than 0, autosuspend will not be allowed for @intf
1403 * or its usb_device. When the driver is finished using @intf it should
1404 * call usb_autopm_put_interface() to decrement the usage counter and
1405 * queue a delayed autosuspend request (if the counter is <= 0).
1408 * Note that @intf->pm_usage_cnt is owned by the interface driver. The
1409 * core will not change its value other than the increment and decrement
1410 * in usb_autopm_get_interface and usb_autopm_put_interface. The driver
1411 * may use this simple counter-oriented discipline or may set the value
1414 * Resume method calls generated by this routine can arrive at any time
1415 * while @intf is suspended. They are not protected by the usb_device's
1416 * lock but only by its pm_mutex. Drivers must provide their own
1419 * This routine can run only in process context.
1421 int usb_autopm_get_interface(struct usb_interface *intf)
1425 status = usb_autopm_do_interface(intf, 1);
1426 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1427 __FUNCTION__, status, intf->pm_usage_cnt);
1430 EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1433 * usb_autopm_set_interface - set a USB interface's autosuspend state
1434 * @intf: the usb_interface whose state should be set
1436 * This routine sets the autosuspend state of @intf's device according
1437 * to @intf's usage counter, which the caller must have set previously.
1438 * If the counter is <= 0, the device is autosuspended (if it isn't
1439 * already suspended and if nothing else prevents the autosuspend). If
1440 * the counter is > 0, the device is autoresumed (if it isn't already
1443 int usb_autopm_set_interface(struct usb_interface *intf)
1447 status = usb_autopm_do_interface(intf, 0);
1448 dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
1449 __FUNCTION__, status, intf->pm_usage_cnt);
1452 EXPORT_SYMBOL_GPL(usb_autopm_set_interface);
1456 void usb_autosuspend_work(struct work_struct *work)
1459 #endif /* CONFIG_USB_SUSPEND */
1462 * usb_external_suspend_device - external suspend of a USB device and its interfaces
1463 * @udev: the usb_device to suspend
1464 * @msg: Power Management message describing this state transition
1466 * This routine handles external suspend requests: ones not generated
1467 * internally by a USB driver (autosuspend) but rather coming from the user
1468 * (via sysfs) or the PM core (system sleep). The suspend will be carried
1469 * out regardless of @udev's usage counter or those of its interfaces,
1470 * and regardless of whether or not remote wakeup is enabled. Of course,
1471 * interface drivers still have the option of failing the suspend (if
1472 * there are unsuspended children, for example).
1474 * The caller must hold @udev's device lock.
1476 int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
1482 status = usb_suspend_both(udev, msg);
1483 usb_pm_unlock(udev);
1488 * usb_external_resume_device - external resume of a USB device and its interfaces
1489 * @udev: the usb_device to resume
1491 * This routine handles external resume requests: ones not generated
1492 * internally by a USB driver (autoresume) but rather coming from the user
1493 * (via sysfs), the PM core (system resume), or the device itself (remote
1494 * wakeup). @udev's usage counter is unaffected.
1496 * The caller must hold @udev's device lock.
1498 int usb_external_resume_device(struct usb_device *udev)
1504 status = usb_resume_both(udev);
1505 udev->last_busy = jiffies;
1506 usb_pm_unlock(udev);
1508 /* Now that the device is awake, we can start trying to autosuspend
1511 usb_try_autosuspend_device(udev);
1515 static int usb_suspend(struct device *dev, pm_message_t message)
1517 if (!is_usb_device(dev)) /* Ignore PM for interfaces */
1519 return usb_external_suspend_device(to_usb_device(dev), message);
1522 static int usb_resume(struct device *dev)
1524 struct usb_device *udev;
1526 if (!is_usb_device(dev)) /* Ignore PM for interfaces */
1528 udev = to_usb_device(dev);
1530 /* If autoresume is disabled then we also want to prevent resume
1531 * during system wakeup. However, a "persistent-device" reset-resume
1532 * after power loss counts as a wakeup event. So allow a
1533 * reset-resume to occur if remote wakeup is enabled. */
1534 if (udev->autoresume_disabled) {
1535 if (!(udev->reset_resume && udev->do_remote_wakeup))
1538 return usb_external_resume_device(udev);
1543 #define usb_suspend NULL
1544 #define usb_resume NULL
1546 #endif /* CONFIG_PM */
1548 struct bus_type usb_bus_type = {
1550 .match = usb_device_match,
1551 .uevent = usb_uevent,
1552 .suspend = usb_suspend,
1553 .resume = usb_resume,