/* * drivers/usb/driver.c - most of the driver model stuff for usb * * (C) Copyright 2005 Greg Kroah-Hartman * * based on drivers/usb/usb.c which had the following copyrights: * (C) Copyright Linus Torvalds 1999 * (C) Copyright Johannes Erdfelt 1999-2001 * (C) Copyright Andreas Gal 1999 * (C) Copyright Gregory P. Smith 1999 * (C) Copyright Deti Fliegl 1999 (new USB architecture) * (C) Copyright Randy Dunlap 2000 * (C) Copyright David Brownell 2000-2004 * (C) Copyright Yggdrasil Computing, Inc. 2000 * (usb_device_id matching changes by Adam J. Richter) * (C) Copyright Greg Kroah-Hartman 2002-2003 * * NOTE! This is not actually a driver at all, rather this is * just a collection of helper routines that implement the * matching, probing, releasing, suspending and resuming for * real drivers. * */ #include #include #include #include #include #include #include "usb.h" #ifdef CONFIG_HOTPLUG /* * Adds a new dynamic USBdevice ID to this driver, * and cause the driver to probe for all devices again. */ ssize_t usb_store_new_id(struct usb_dynids *dynids, struct device_driver *driver, const char *buf, size_t count) { struct usb_dynid *dynid; u32 idVendor = 0; u32 idProduct = 0; unsigned int bInterfaceClass = 0; int fields = 0; int retval = 0; fields = sscanf(buf, "%x %x %x", &idVendor, &idProduct, &bInterfaceClass); if (fields < 2) return -EINVAL; dynid = kzalloc(sizeof(*dynid), GFP_KERNEL); if (!dynid) return -ENOMEM; INIT_LIST_HEAD(&dynid->node); dynid->id.idVendor = idVendor; dynid->id.idProduct = idProduct; dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE; if (fields == 3) { dynid->id.bInterfaceClass = (u8)bInterfaceClass; dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS; } spin_lock(&dynids->lock); list_add_tail(&dynid->node, &dynids->list); spin_unlock(&dynids->lock); retval = driver_attach(driver); if (retval) return retval; return count; } EXPORT_SYMBOL_GPL(usb_store_new_id); ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf) { struct usb_dynid *dynid; size_t count = 0; list_for_each_entry(dynid, &dynids->list, node) if (dynid->id.bInterfaceClass != 0) count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x %02x\n", dynid->id.idVendor, dynid->id.idProduct, dynid->id.bInterfaceClass); else count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x\n", dynid->id.idVendor, dynid->id.idProduct); return count; } EXPORT_SYMBOL_GPL(usb_show_dynids); static ssize_t show_dynids(struct device_driver *driver, char *buf) { struct usb_driver *usb_drv = to_usb_driver(driver); return usb_show_dynids(&usb_drv->dynids, buf); } static ssize_t store_new_id(struct device_driver *driver, const char *buf, size_t count) { struct usb_driver *usb_drv = to_usb_driver(driver); return usb_store_new_id(&usb_drv->dynids, driver, buf, count); } static DRIVER_ATTR(new_id, S_IRUGO | S_IWUSR, show_dynids, store_new_id); /** * store_remove_id - remove a USB device ID from this driver * @driver: target device driver * @buf: buffer for scanning device ID data * @count: input size * * Removes a dynamic usb device ID from this driver. */ static ssize_t store_remove_id(struct device_driver *driver, const char *buf, size_t count) { struct usb_dynid *dynid, *n; struct usb_driver *usb_driver = to_usb_driver(driver); u32 idVendor = 0; u32 idProduct = 0; int fields = 0; int retval = 0; fields = sscanf(buf, "%x %x", &idVendor, &idProduct); if (fields < 2) return -EINVAL; spin_lock(&usb_driver->dynids.lock); list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) { struct usb_device_id *id = &dynid->id; if ((id->idVendor == idVendor) && (id->idProduct == idProduct)) { list_del(&dynid->node); kfree(dynid); retval = 0; break; } } spin_unlock(&usb_driver->dynids.lock); if (retval) return retval; return count; } static DRIVER_ATTR(remove_id, S_IRUGO | S_IWUSR, show_dynids, store_remove_id); static int usb_create_newid_files(struct usb_driver *usb_drv) { int error = 0; if (usb_drv->no_dynamic_id) goto exit; if (usb_drv->probe != NULL) { error = driver_create_file(&usb_drv->drvwrap.driver, &driver_attr_new_id); if (error == 0) { error = driver_create_file(&usb_drv->drvwrap.driver, &driver_attr_remove_id); if (error) driver_remove_file(&usb_drv->drvwrap.driver, &driver_attr_new_id); } } exit: return error; } static void usb_remove_newid_files(struct usb_driver *usb_drv) { if (usb_drv->no_dynamic_id) return; if (usb_drv->probe != NULL) { driver_remove_file(&usb_drv->drvwrap.driver, &driver_attr_remove_id); driver_remove_file(&usb_drv->drvwrap.driver, &driver_attr_new_id); } } static void usb_free_dynids(struct usb_driver *usb_drv) { struct usb_dynid *dynid, *n; spin_lock(&usb_drv->dynids.lock); list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) { list_del(&dynid->node); kfree(dynid); } spin_unlock(&usb_drv->dynids.lock); } #else static inline int usb_create_newid_files(struct usb_driver *usb_drv) { return 0; } static void usb_remove_newid_files(struct usb_driver *usb_drv) { } static inline void usb_free_dynids(struct usb_driver *usb_drv) { } #endif static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf, struct usb_driver *drv) { struct usb_dynid *dynid; spin_lock(&drv->dynids.lock); list_for_each_entry(dynid, &drv->dynids.list, node) { if (usb_match_one_id(intf, &dynid->id)) { spin_unlock(&drv->dynids.lock); return &dynid->id; } } spin_unlock(&drv->dynids.lock); return NULL; } /* called from driver core with dev locked */ static int usb_probe_device(struct device *dev) { struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); struct usb_device *udev = to_usb_device(dev); int error = 0; dev_dbg(dev, "%s\n", __func__); /* TODO: Add real matching code */ /* The device should always appear to be in use * unless the driver suports autosuspend. */ if (!udriver->supports_autosuspend) error = usb_autoresume_device(udev); if (!error) error = udriver->probe(udev); return error; } /* called from driver core with dev locked */ static int usb_unbind_device(struct device *dev) { struct usb_device *udev = to_usb_device(dev); struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); udriver->disconnect(udev); if (!udriver->supports_autosuspend) usb_autosuspend_device(udev); return 0; } /* * Cancel any pending scheduled resets * * [see usb_queue_reset_device()] * * Called after unconfiguring / when releasing interfaces. See * comments in __usb_queue_reset_device() regarding * udev->reset_running. */ static void usb_cancel_queued_reset(struct usb_interface *iface) { if (iface->reset_running == 0) cancel_work_sync(&iface->reset_ws); } /* called from driver core with dev locked */ static int usb_probe_interface(struct device *dev) { struct usb_driver *driver = to_usb_driver(dev->driver); struct usb_interface *intf = to_usb_interface(dev); struct usb_device *udev = interface_to_usbdev(intf); const struct usb_device_id *id; int error = -ENODEV; int lpm_disable_error; dev_dbg(dev, "%s\n", __func__); intf->needs_binding = 0; if (usb_device_is_owned(udev)) return error; if (udev->authorized == 0) { dev_err(&intf->dev, "Device is not authorized for usage\n"); return error; } id = usb_match_id(intf, driver->id_table); if (!id) id = usb_match_dynamic_id(intf, driver); if (!id) return error; dev_dbg(dev, "%s - got id\n", __func__); error = usb_autoresume_device(udev); if (error) return error; intf->condition = USB_INTERFACE_BINDING; /* Probed interfaces are initially active. They are * runtime-PM-enabled only if the driver has autosuspend support. * They are sensitive to their children's power states. */ pm_runtime_set_active(dev); pm_suspend_ignore_children(dev, false); if (driver->supports_autosuspend) pm_runtime_enable(dev); /* If the new driver doesn't allow hub-initiated LPM, and we can't * disable hub-initiated LPM, then fail the probe. * * Otherwise, leaving LPM enabled should be harmless, because the * endpoint intervals should remain the same, and the U1/U2 timeouts * should remain the same. * * If we need to install alt setting 0 before probe, or another alt * setting during probe, that should also be fine. usb_set_interface() * will attempt to disable LPM, and fail if it can't disable it. */ lpm_disable_error = usb_unlocked_disable_lpm(udev); if (lpm_disable_error && driver->disable_hub_initiated_lpm) { dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n.", __func__, driver->name); error = lpm_disable_error; goto err; } /* Carry out a deferred switch to altsetting 0 */ if (intf->needs_altsetting0) { error = usb_set_interface(udev, intf->altsetting[0]. desc.bInterfaceNumber, 0); if (error < 0) goto err; intf->needs_altsetting0 = 0; } error = driver->probe(intf, id); if (error) goto err; intf->condition = USB_INTERFACE_BOUND; /* If the LPM disable succeeded, balance the ref counts. */ if (!lpm_disable_error) usb_unlocked_enable_lpm(udev); usb_autosuspend_device(udev); return error; err: usb_set_intfdata(intf, NULL); intf->needs_remote_wakeup = 0; intf->condition = USB_INTERFACE_UNBOUND; usb_cancel_queued_reset(intf); /* If the LPM disable succeeded, balance the ref counts. */ if (!lpm_disable_error) usb_unlocked_enable_lpm(udev); /* Unbound interfaces are always runtime-PM-disabled and -suspended */ if (driver->supports_autosuspend) pm_runtime_disable(dev); pm_runtime_set_suspended(dev); usb_autosuspend_device(udev); return error; } /* called from driver core with dev locked */ static int usb_unbind_interface(struct device *dev) { struct usb_driver *driver = to_usb_driver(dev->driver); struct usb_interface *intf = to_usb_interface(dev); struct usb_device *udev; int error, r, lpm_disable_error; intf->condition = USB_INTERFACE_UNBINDING; /* Autoresume for set_interface call below */ udev = interface_to_usbdev(intf); error = usb_autoresume_device(udev); /* Hub-initiated LPM policy may change, so attempt to disable LPM until * the driver is unbound. If LPM isn't disabled, that's fine because it * wouldn't be enabled unless all the bound interfaces supported * hub-initiated LPM. */ lpm_disable_error = usb_unlocked_disable_lpm(udev); /* Terminate all URBs for this interface unless the driver * supports "soft" unbinding. */ if (!driver->soft_unbind) usb_disable_interface(udev, intf, false); driver->disconnect(intf); usb_cancel_queued_reset(intf); /* Reset other interface state. * We cannot do a Set-Interface if the device is suspended or * if it is prepared for a system sleep (since installing a new * altsetting means creating new endpoint device entries). * When either of these happens, defer the Set-Interface. */ if (intf->cur_altsetting->desc.bAlternateSetting == 0) { /* Already in altsetting 0 so skip Set-Interface. * Just re-enable it without affecting the endpoint toggles. */ usb_enable_interface(udev, intf, false); } else if (!error && !intf->dev.power.is_prepared) { r = usb_set_interface(udev, intf->altsetting[0]. desc.bInterfaceNumber, 0); if (r < 0) intf->needs_altsetting0 = 1; } else { intf->needs_altsetting0 = 1; } usb_set_intfdata(intf, NULL); intf->condition = USB_INTERFACE_UNBOUND; intf->needs_remote_wakeup = 0; /* Attempt to re-enable USB3 LPM, if the disable succeeded. */ if (!lpm_disable_error) usb_unlocked_enable_lpm(udev); /* Unbound interfaces are always runtime-PM-disabled and -suspended */ if (driver->supports_autosuspend) pm_runtime_disable(dev); pm_runtime_set_suspended(dev); /* Undo any residual pm_autopm_get_interface_* calls */ for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r) usb_autopm_put_interface_no_suspend(intf); atomic_set(&intf->pm_usage_cnt, 0); if (!error) usb_autosuspend_device(udev); return 0; } /** * usb_driver_claim_interface - bind a driver to an interface * @driver: the driver to be bound * @iface: the interface to which it will be bound; must be in the * usb device's active configuration * @priv: driver data associated with that interface * * This is used by usb device drivers that need to claim more than one * interface on a device when probing (audio and acm are current examples). * No device driver should directly modify internal usb_interface or * usb_device structure members. * * Few drivers should need to use this routine, since the most natural * way to bind to an interface is to return the private data from * the driver's probe() method. * * Callers must own the device lock, so driver probe() entries don't need * extra locking, but other call contexts may need to explicitly claim that * lock. */ int usb_driver_claim_interface(struct usb_driver *driver, struct usb_interface *iface, void *priv) { struct device *dev = &iface->dev; struct usb_device *udev; int retval = 0; int lpm_disable_error; if (dev->driver) return -EBUSY; udev = interface_to_usbdev(iface); dev->driver = &driver->drvwrap.driver; usb_set_intfdata(iface, priv); iface->needs_binding = 0; iface->condition = USB_INTERFACE_BOUND; /* Disable LPM until this driver is bound. */ lpm_disable_error = usb_unlocked_disable_lpm(udev); if (lpm_disable_error && driver->disable_hub_initiated_lpm) { dev_err(&iface->dev, "%s Failed to disable LPM for driver %s\n.", __func__, driver->name); return -ENOMEM; } /* Claimed interfaces are initially inactive (suspended) and * runtime-PM-enabled, but only if the driver has autosuspend * support. Otherwise they are marked active, to prevent the * device from being autosuspended, but left disabled. In either * case they are sensitive to their children's power states. */ pm_suspend_ignore_children(dev, false); if (driver->supports_autosuspend) pm_runtime_enable(dev); else pm_runtime_set_active(dev); /* if interface was already added, bind now; else let * the future device_add() bind it, bypassing probe() */ if (device_is_registered(dev)) retval = device_bind_driver(dev); /* Attempt to re-enable USB3 LPM, if the disable was successful. */ if (!lpm_disable_error) usb_unlocked_enable_lpm(udev); return retval; } EXPORT_SYMBOL_GPL(usb_driver_claim_interface); /** * usb_driver_release_interface - unbind a driver from an interface * @driver: the driver to be unbound * @iface: the interface from which it will be unbound * * This can be used by drivers to release an interface without waiting * for their disconnect() methods to be called. In typical cases this * also causes the driver disconnect() method to be called. * * This call is synchronous, and may not be used in an interrupt context. * Callers must own the device lock, so driver disconnect() entries don't * need extra locking, but other call contexts may need to explicitly claim * that lock. */ void usb_driver_release_interface(struct usb_driver *driver, struct usb_interface *iface) { struct device *dev = &iface->dev; /* this should never happen, don't release something that's not ours */ if (!dev->driver || dev->driver != &driver->drvwrap.driver) return; /* don't release from within disconnect() */ if (iface->condition != USB_INTERFACE_BOUND) return; iface->condition = USB_INTERFACE_UNBINDING; /* Release via the driver core only if the interface * has already been registered */ if (device_is_registered(dev)) { device_release_driver(dev); } else { device_lock(dev); usb_unbind_interface(dev); dev->driver = NULL; device_unlock(dev); } } EXPORT_SYMBOL_GPL(usb_driver_release_interface); /* returns 0 if no match, 1 if match */ int usb_match_device(struct usb_device *dev, const struct usb_device_id *id) { if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) && id->idVendor != le16_to_cpu(dev->descriptor.idVendor)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) && id->idProduct != le16_to_cpu(dev->descriptor.idProduct)) return 0; /* No need to test id->bcdDevice_lo != 0, since 0 is never greater than any unsigned number. */ if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) && (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice))) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) && (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice))) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) && (id->bDeviceClass != dev->descriptor.bDeviceClass)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) && (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) && (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol)) return 0; return 1; } /* returns 0 if no match, 1 if match */ int usb_match_one_id_intf(struct usb_device *dev, struct usb_host_interface *intf, const struct usb_device_id *id) { /* The interface class, subclass, protocol and number should never be * checked for a match if the device class is Vendor Specific, * unless the match record specifies the Vendor ID. */ if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC && !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) && (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS | USB_DEVICE_ID_MATCH_INT_PROTOCOL | USB_DEVICE_ID_MATCH_INT_NUMBER))) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) && (id->bInterfaceClass != intf->desc.bInterfaceClass)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) && (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) && (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) && (id->bInterfaceNumber != intf->desc.bInterfaceNumber)) return 0; return 1; } /* returns 0 if no match, 1 if match */ int usb_match_one_id(struct usb_interface *interface, const struct usb_device_id *id) { struct usb_host_interface *intf; struct usb_device *dev; /* proc_connectinfo in devio.c may call us with id == NULL. */ if (id == NULL) return 0; intf = interface->cur_altsetting; dev = interface_to_usbdev(interface); if (!usb_match_device(dev, id)) return 0; return usb_match_one_id_intf(dev, intf, id); } EXPORT_SYMBOL_GPL(usb_match_one_id); /** * usb_match_id - find first usb_device_id matching device or interface * @interface: the interface of interest * @id: array of usb_device_id structures, terminated by zero entry * * usb_match_id searches an array of usb_device_id's and returns * the first one matching the device or interface, or null. * This is used when binding (or rebinding) a driver to an interface. * Most USB device drivers will use this indirectly, through the usb core, * but some layered driver frameworks use it directly. * These device tables are exported with MODULE_DEVICE_TABLE, through * modutils, to support the driver loading functionality of USB hotplugging. * * What Matches: * * The "match_flags" element in a usb_device_id controls which * members are used. If the corresponding bit is set, the * value in the device_id must match its corresponding member * in the device or interface descriptor, or else the device_id * does not match. * * "driver_info" is normally used only by device drivers, * but you can create a wildcard "matches anything" usb_device_id * as a driver's "modules.usbmap" entry if you provide an id with * only a nonzero "driver_info" field. If you do this, the USB device * driver's probe() routine should use additional intelligence to * decide whether to bind to the specified interface. * * What Makes Good usb_device_id Tables: * * The match algorithm is very simple, so that intelligence in * driver selection must come from smart driver id records. * Unless you have good reasons to use another selection policy, * provide match elements only in related groups, and order match * specifiers from specific to general. Use the macros provided * for that purpose if you can. * * The most specific match specifiers use device descriptor * data. These are commonly used with product-specific matches; * the USB_DEVICE macro lets you provide vendor and product IDs, * and you can also match against ranges of product revisions. * These are widely used for devices with application or vendor * specific bDeviceClass values. * * Matches based on device class/subclass/protocol specifications * are slightly more general; use the USB_DEVICE_INFO macro, or * its siblings. These are used with single-function devices * where bDeviceClass doesn't specify that each interface has * its own class. * * Matches based on interface class/subclass/protocol are the * most general; they let drivers bind to any interface on a * multiple-function device. Use the USB_INTERFACE_INFO * macro, or its siblings, to match class-per-interface style * devices (as recorded in bInterfaceClass). * * Note that an entry created by USB_INTERFACE_INFO won't match * any interface if the device class is set to Vendor-Specific. * This is deliberate; according to the USB spec the meanings of * the interface class/subclass/protocol for these devices are also * vendor-specific, and hence matching against a standard product * class wouldn't work anyway. If you really want to use an * interface-based match for such a device, create a match record * that also specifies the vendor ID. (Unforunately there isn't a * standard macro for creating records like this.) * * Within those groups, remember that not all combinations are * meaningful. For example, don't give a product version range * without vendor and product IDs; or specify a protocol without * its associated class and subclass. */ const struct usb_device_id *usb_match_id(struct usb_interface *interface, const struct usb_device_id *id) { /* proc_connectinfo in devio.c may call us with id == NULL. */ if (id == NULL) return NULL; /* It is important to check that id->driver_info is nonzero, since an entry that is all zeroes except for a nonzero id->driver_info is the way to create an entry that indicates that the driver want to examine every device and interface. */ for (; id->idVendor || id->idProduct || id->bDeviceClass || id->bInterfaceClass || id->driver_info; id++) { if (usb_match_one_id(interface, id)) return id; } return NULL; } EXPORT_SYMBOL_GPL(usb_match_id); static int usb_device_match(struct device *dev, struct device_driver *drv) { /* devices and interfaces are handled separately */ if (is_usb_device(dev)) { /* interface drivers never match devices */ if (!is_usb_device_driver(drv)) return 0; /* TODO: Add real matching code */ return 1; } else if (is_usb_interface(dev)) { struct usb_interface *intf; struct usb_driver *usb_drv; const struct usb_device_id *id; /* device drivers never match interfaces */ if (is_usb_device_driver(drv)) return 0; intf = to_usb_interface(dev); usb_drv = to_usb_driver(drv); id = usb_match_id(intf, usb_drv->id_table); if (id) return 1; id = usb_match_dynamic_id(intf, usb_drv); if (id) return 1; } return 0; } #ifdef CONFIG_HOTPLUG static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) { struct usb_device *usb_dev; if (is_usb_device(dev)) { usb_dev = to_usb_device(dev); } else if (is_usb_interface(dev)) { struct usb_interface *intf = to_usb_interface(dev); usb_dev = interface_to_usbdev(intf); } else { return 0; } if (usb_dev->devnum < 0) { /* driver is often null here; dev_dbg() would oops */ pr_debug("usb %s: already deleted?\n", dev_name(dev)); return -ENODEV; } if (!usb_dev->bus) { pr_debug("usb %s: bus removed?\n", dev_name(dev)); return -ENODEV; } /* per-device configurations are common */ if (add_uevent_var(env, "PRODUCT=%x/%x/%x", le16_to_cpu(usb_dev->descriptor.idVendor), le16_to_cpu(usb_dev->descriptor.idProduct), le16_to_cpu(usb_dev->descriptor.bcdDevice))) return -ENOMEM; /* class-based driver binding models */ if (add_uevent_var(env, "TYPE=%d/%d/%d", usb_dev->descriptor.bDeviceClass, usb_dev->descriptor.bDeviceSubClass, usb_dev->descriptor.bDeviceProtocol)) return -ENOMEM; return 0; } #else static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) { return -ENODEV; } #endif /* CONFIG_HOTPLUG */ /** * usb_register_device_driver - register a USB device (not interface) driver * @new_udriver: USB operations for the device driver * @owner: module owner of this driver. * * Registers a USB device driver with the USB core. The list of * unattached devices will be rescanned whenever a new driver is * added, allowing the new driver to attach to any recognized devices. * Returns a negative error code on failure and 0 on success. */ int usb_register_device_driver(struct usb_device_driver *new_udriver, struct module *owner) { int retval = 0; if (usb_disabled()) return -ENODEV; new_udriver->drvwrap.for_devices = 1; new_udriver->drvwrap.driver.name = (char *) new_udriver->name; new_udriver->drvwrap.driver.bus = &usb_bus_type; new_udriver->drvwrap.driver.probe = usb_probe_device; new_udriver->drvwrap.driver.remove = usb_unbind_device; new_udriver->drvwrap.driver.owner = owner; retval = driver_register(&new_udriver->drvwrap.driver); if (!retval) pr_info("%s: registered new device driver %s\n", usbcore_name, new_udriver->name); else printk(KERN_ERR "%s: error %d registering device " " driver %s\n", usbcore_name, retval, new_udriver->name); return retval; } EXPORT_SYMBOL_GPL(usb_register_device_driver); /** * usb_deregister_device_driver - unregister a USB device (not interface) driver * @udriver: USB operations of the device driver to unregister * Context: must be able to sleep * * Unlinks the specified driver from the internal USB driver list. */ void usb_deregister_device_driver(struct usb_device_driver *udriver) { pr_info("%s: deregistering device driver %s\n", usbcore_name, udriver->name); driver_unregister(&udriver->drvwrap.driver); } EXPORT_SYMBOL_GPL(usb_deregister_device_driver); /** * usb_register_driver - register a USB interface driver * @new_driver: USB operations for the interface driver * @owner: module owner of this driver. * @mod_name: module name string * * Registers a USB interface driver with the USB core. The list of * unattached interfaces will be rescanned whenever a new driver is * added, allowing the new driver to attach to any recognized interfaces. * Returns a negative error code on failure and 0 on success. * * NOTE: if you want your driver to use the USB major number, you must call * usb_register_dev() to enable that functionality. This function no longer * takes care of that. */ int usb_register_driver(struct usb_driver *new_driver, struct module *owner, const char *mod_name) { int retval = 0; if (usb_disabled()) return -ENODEV; new_driver->drvwrap.for_devices = 0; new_driver->drvwrap.driver.name = (char *) new_driver->name; new_driver->drvwrap.driver.bus = &usb_bus_type; new_driver->drvwrap.driver.probe = usb_probe_interface; new_driver->drvwrap.driver.remove = usb_unbind_interface; new_driver->drvwrap.driver.owner = owner; new_driver->drvwrap.driver.mod_name = mod_name; spin_lock_init(&new_driver->dynids.lock); INIT_LIST_HEAD(&new_driver->dynids.list); retval = driver_register(&new_driver->drvwrap.driver); if (retval) goto out; retval = usb_create_newid_files(new_driver); if (retval) goto out_newid; pr_info("%s: registered new interface driver %s\n", usbcore_name, new_driver->name); out: return retval; out_newid: driver_unregister(&new_driver->drvwrap.driver); printk(KERN_ERR "%s: error %d registering interface " " driver %s\n", usbcore_name, retval, new_driver->name); goto out; } EXPORT_SYMBOL_GPL(usb_register_driver); /** * usb_deregister - unregister a USB interface driver * @driver: USB operations of the interface driver to unregister * Context: must be able to sleep * * Unlinks the specified driver from the internal USB driver list. * * NOTE: If you called usb_register_dev(), you still need to call * usb_deregister_dev() to clean up your driver's allocated minor numbers, * this * call will no longer do it for you. */ void usb_deregister(struct usb_driver *driver) { pr_info("%s: deregistering interface driver %s\n", usbcore_name, driver->name); usb_remove_newid_files(driver); driver_unregister(&driver->drvwrap.driver); usb_free_dynids(driver); } EXPORT_SYMBOL_GPL(usb_deregister); /* Forced unbinding of a USB interface driver, either because * it doesn't support pre_reset/post_reset/reset_resume or * because it doesn't support suspend/resume. * * The caller must hold @intf's device's lock, but not its pm_mutex * and not @intf->dev.sem. */ void usb_forced_unbind_intf(struct usb_interface *intf) { struct usb_driver *driver = to_usb_driver(intf->dev.driver); dev_dbg(&intf->dev, "forced unbind\n"); usb_driver_release_interface(driver, intf); /* Mark the interface for later rebinding */ intf->needs_binding = 1; } /* Delayed forced unbinding of a USB interface driver and scan * for rebinding. * * The caller must hold @intf's device's lock, but not its pm_mutex * and not @intf->dev.sem. * * Note: Rebinds will be skipped if a system sleep transition is in * progress and the PM "complete" callback hasn't occurred yet. */ void usb_rebind_intf(struct usb_interface *intf) { int rc; /* Delayed unbind of an existing driver */ if (intf->dev.driver) usb_forced_unbind_intf(intf); /* Try to rebind the interface */ if (!intf->dev.power.is_prepared) { intf->needs_binding = 0; rc = device_attach(&intf->dev); if (rc < 0) dev_warn(&intf->dev, "rebind failed: %d\n", rc); } } #ifdef CONFIG_PM /* Unbind drivers for @udev's interfaces that don't support suspend/resume * There is no check for reset_resume here because it can be determined * only during resume whether reset_resume is needed. * * The caller must hold @udev's device lock. */ static void unbind_no_pm_drivers_interfaces(struct usb_device *udev) { struct usb_host_config *config; int i; struct usb_interface *intf; struct usb_driver *drv; config = udev->actconfig; if (config) { for (i = 0; i < config->desc.bNumInterfaces; ++i) { intf = config->interface[i]; if (intf->dev.driver) { drv = to_usb_driver(intf->dev.driver); if (!drv->suspend || !drv->resume) usb_forced_unbind_intf(intf); } } } } /* Unbind drivers for @udev's interfaces that failed to support reset-resume. * These interfaces have the needs_binding flag set by usb_resume_interface(). * * The caller must hold @udev's device lock. */ static void unbind_no_reset_resume_drivers_interfaces(struct usb_device *udev) { struct usb_host_config *config; int i; struct usb_interface *intf; config = udev->actconfig; if (config) { for (i = 0; i < config->desc.bNumInterfaces; ++i) { intf = config->interface[i]; if (intf->dev.driver && intf->needs_binding) usb_forced_unbind_intf(intf); } } } static void do_rebind_interfaces(struct usb_device *udev) { struct usb_host_config *config; int i; struct usb_interface *intf; config = udev->actconfig; if (config) { for (i = 0; i < config->desc.bNumInterfaces; ++i) { intf = config->interface[i]; if (intf->needs_binding) usb_rebind_intf(intf); } } } static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) { struct usb_device_driver *udriver; int status = 0; if (udev->state == USB_STATE_NOTATTACHED || udev->state == USB_STATE_SUSPENDED) goto done; /* For devices that don't have a driver, we do a generic suspend. */ if (udev->dev.driver) udriver = to_usb_device_driver(udev->dev.driver); else { udev->do_remote_wakeup = 0; udriver = &usb_generic_driver; } status = udriver->suspend(udev, msg); done: dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); return status; } static int usb_resume_device(struct usb_device *udev, pm_message_t msg) { struct usb_device_driver *udriver; int status = 0; if (udev->state == USB_STATE_NOTATTACHED) goto done; /* Can't resume it if it doesn't have a driver. */ if (udev->dev.driver == NULL) { status = -ENOTCONN; goto done; } /* Non-root devices on a full/low-speed bus must wait for their * companion high-speed root hub, in case a handoff is needed. */ if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion) device_pm_wait_for_dev(&udev->dev, &udev->bus->hs_companion->root_hub->dev); if (udev->quirks & USB_QUIRK_RESET_RESUME) udev->reset_resume = 1; udriver = to_usb_device_driver(udev->dev.driver); status = udriver->resume(udev, msg); done: dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); return status; } static int usb_suspend_interface(struct usb_device *udev, struct usb_interface *intf, pm_message_t msg) { struct usb_driver *driver; int status = 0; if (udev->state == USB_STATE_NOTATTACHED || intf->condition == USB_INTERFACE_UNBOUND) goto done; driver = to_usb_driver(intf->dev.driver); /* at this time we know the driver supports suspend */ status = driver->suspend(intf, msg); if (status && !PMSG_IS_AUTO(msg)) dev_err(&intf->dev, "suspend error %d\n", status); done: dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status); return status; } static int usb_resume_interface(struct usb_device *udev, struct usb_interface *intf, pm_message_t msg, int reset_resume) { struct usb_driver *driver; int status = 0; if (udev->state == USB_STATE_NOTATTACHED) goto done; /* Don't let autoresume interfere with unbinding */ if (intf->condition == USB_INTERFACE_UNBINDING) goto done; /* Can't resume it if it doesn't have a driver. */ if (intf->condition == USB_INTERFACE_UNBOUND) { /* Carry out a deferred switch to altsetting 0 */ if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) { usb_set_interface(udev, intf->altsetting[0]. desc.bInterfaceNumber, 0); intf->needs_altsetting0 = 0; } goto done; } /* Don't resume if the interface is marked for rebinding */ if (intf->needs_binding) goto done; driver = to_usb_driver(intf->dev.driver); if (reset_resume) { if (driver->reset_resume) { status = driver->reset_resume(intf); if (status) dev_err(&intf->dev, "%s error %d\n", "reset_resume", status); } else { intf->needs_binding = 1; dev_warn(&intf->dev, "no %s for driver %s?\n", "reset_resume", driver->name); } } else { status = driver->resume(intf); if (status) dev_err(&intf->dev, "resume error %d\n", status); } done: dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status); /* Later we will unbind the driver and/or reprobe, if necessary */ return status; } /** * usb_suspend_both - suspend a USB device and its interfaces * @udev: the usb_device to suspend * @msg: Power Management message describing this state transition * * This is the central routine for suspending USB devices. It calls the * suspend methods for all the interface drivers in @udev and then calls * the suspend method for @udev itself. If an error occurs at any stage, * all the interfaces which were suspended are resumed so that they remain * in the same state as the device. * * Autosuspend requests originating from a child device or an interface * driver may be made without the protection of @udev's device lock, but * all other suspend calls will hold the lock. Usbcore will insure that * method calls do not arrive during bind, unbind, or reset operations. * However drivers must be prepared to handle suspend calls arriving at * unpredictable times. * * This routine can run only in process context. */ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) { int status = 0; int i = 0, n = 0; struct usb_interface *intf; if (udev->state == USB_STATE_NOTATTACHED || udev->state == USB_STATE_SUSPENDED) goto done; /* Suspend all the interfaces and then udev itself */ if (udev->actconfig) { n = udev->actconfig->desc.bNumInterfaces; for (i = n - 1; i >= 0; --i) { intf = udev->actconfig->interface[i]; status = usb_suspend_interface(udev, intf, msg); /* Ignore errors during system sleep transitions */ if (!PMSG_IS_AUTO(msg)) status = 0; if (status != 0) break; } } if (status == 0) { status = usb_suspend_device(udev, msg); /* * Ignore errors from non-root-hub devices during * system sleep transitions. For the most part, * these devices should go to low power anyway when * the entire bus is suspended. */ if (udev->parent && !PMSG_IS_AUTO(msg)) status = 0; } /* If the suspend failed, resume interfaces that did get suspended */ if (status != 0) { msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME); while (++i < n) { intf = udev->actconfig->interface[i]; usb_resume_interface(udev, intf, msg, 0); } /* If the suspend succeeded then prevent any more URB submissions * and flush any outstanding URBs. */ } else { udev->can_submit = 0; for (i = 0; i < 16; ++i) { usb_hcd_flush_endpoint(udev, udev->ep_out[i]); usb_hcd_flush_endpoint(udev, udev->ep_in[i]); } } done: dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); return status; } /** * usb_resume_both - resume a USB device and its interfaces * @udev: the usb_device to resume * @msg: Power Management message describing this state transition * * This is the central routine for resuming USB devices. It calls the * the resume method for @udev and then calls the resume methods for all * the interface drivers in @udev. * * Autoresume requests originating from a child device or an interface * driver may be made without the protection of @udev's device lock, but * all other resume calls will hold the lock. Usbcore will insure that * method calls do not arrive during bind, unbind, or reset operations. * However drivers must be prepared to handle resume calls arriving at * unpredictable times. * * This routine can run only in process context. */ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) { int status = 0; int i; struct usb_interface *intf; if (udev->state == USB_STATE_NOTATTACHED) { status = -ENODEV; goto done; } udev->can_submit = 1; /* Resume the device */ if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) status = usb_resume_device(udev, msg); /* Resume the interfaces */ if (status == 0 && udev->actconfig) { for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { intf = udev->actconfig->interface[i]; usb_resume_interface(udev, intf, msg, udev->reset_resume); } } usb_mark_last_busy(udev); done: dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); if (!status) udev->reset_resume = 0; return status; } static void choose_wakeup(struct usb_device *udev, pm_message_t msg) { int w; /* Remote wakeup is needed only when we actually go to sleep. * For things like FREEZE and QUIESCE, if the device is already * autosuspended then its current wakeup setting is okay. */ if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) { if (udev->state != USB_STATE_SUSPENDED) udev->do_remote_wakeup = 0; return; } /* Enable remote wakeup if it is allowed, even if no interface drivers * actually want it. */ w = device_may_wakeup(&udev->dev); /* If the device is autosuspended with the wrong wakeup setting, * autoresume now so the setting can be changed. */ if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup) pm_runtime_resume(&udev->dev); udev->do_remote_wakeup = w; } /* The device lock is held by the PM core */ int usb_suspend(struct device *dev, pm_message_t msg) { struct usb_device *udev = to_usb_device(dev); unbind_no_pm_drivers_interfaces(udev); /* From now on we are sure all drivers support suspend/resume * but not necessarily reset_resume() * so we may still need to unbind and rebind upon resume */ choose_wakeup(udev, msg); return usb_suspend_both(udev, msg); } /* The device lock is held by the PM core */ int usb_resume_complete(struct device *dev) { struct usb_device *udev = to_usb_device(dev); /* For PM complete calls, all we do is rebind interfaces * whose needs_binding flag is set */ if (udev->state != USB_STATE_NOTATTACHED) do_rebind_interfaces(udev); return 0; } /* The device lock is held by the PM core */ int usb_resume(struct device *dev, pm_message_t msg) { struct usb_device *udev = to_usb_device(dev); int status; /* For all calls, take the device back to full power and * tell the PM core in case it was autosuspended previously. * Unbind the interfaces that will need rebinding later, * because they fail to support reset_resume. * (This can't be done in usb_resume_interface() * above because it doesn't own the right set of locks.) */ status = usb_resume_both(udev, msg); if (status == 0) { pm_runtime_disable(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); unbind_no_reset_resume_drivers_interfaces(udev); } /* Avoid PM error messages for devices disconnected while suspended * as we'll display regular disconnect messages just a bit later. */ if (status == -ENODEV || status == -ESHUTDOWN) status = 0; return status; } #endif /* CONFIG_PM */ #ifdef CONFIG_USB_SUSPEND /** * usb_enable_autosuspend - allow a USB device to be autosuspended * @udev: the USB device which may be autosuspended * * This routine allows @udev to be autosuspended. An autosuspend won't * take place until the autosuspend_delay has elapsed and all the other * necessary conditions are satisfied. * * The caller must hold @udev's device lock. */ void usb_enable_autosuspend(struct usb_device *udev) { pm_runtime_allow(&udev->dev); } EXPORT_SYMBOL_GPL(usb_enable_autosuspend); /** * usb_disable_autosuspend - prevent a USB device from being autosuspended * @udev: the USB device which may not be autosuspended * * This routine prevents @udev from being autosuspended and wakes it up * if it is already autosuspended. * * The caller must hold @udev's device lock. */ void usb_disable_autosuspend(struct usb_device *udev) { pm_runtime_forbid(&udev->dev); } EXPORT_SYMBOL_GPL(usb_disable_autosuspend); /** * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces * @udev: the usb_device to autosuspend * * This routine should be called when a core subsystem is finished using * @udev and wants to allow it to autosuspend. Examples would be when * @udev's device file in usbfs is closed or after a configuration change. * * @udev's usage counter is decremented; if it drops to 0 and all the * interfaces are inactive then a delayed autosuspend will be attempted. * The attempt may fail (see autosuspend_check()). * * The caller must hold @udev's device lock. * * This routine can run only in process context. */ void usb_autosuspend_device(struct usb_device *udev) { int status; usb_mark_last_busy(udev); status = pm_runtime_put_sync_autosuspend(&udev->dev); dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n", __func__, atomic_read(&udev->dev.power.usage_count), status); } /** * usb_autoresume_device - immediately autoresume a USB device and its interfaces * @udev: the usb_device to autoresume * * This routine should be called when a core subsystem wants to use @udev * and needs to guarantee that it is not suspended. No autosuspend will * occur until usb_autosuspend_device() is called. (Note that this will * not prevent suspend events originating in the PM core.) Examples would * be when @udev's device file in usbfs is opened or when a remote-wakeup * request is received. * * @udev's usage counter is incremented to prevent subsequent autosuspends. * However if the autoresume fails then the usage counter is re-decremented. * * The caller must hold @udev's device lock. * * This routine can run only in process context. */ int usb_autoresume_device(struct usb_device *udev) { int status; status = pm_runtime_get_sync(&udev->dev); if (status < 0) pm_runtime_put_sync(&udev->dev); dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n", __func__, atomic_read(&udev->dev.power.usage_count), status); if (status > 0) status = 0; return status; } /** * usb_autopm_put_interface - decrement a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be decremented * * This routine should be called by an interface driver when it is * finished using @intf and wants to allow it to autosuspend. A typical * example would be a character-device driver when its device file is * closed. * * The routine decrements @intf's usage counter. When the counter reaches * 0, a delayed autosuspend request for @intf's device is attempted. The * attempt may fail (see autosuspend_check()). * * This routine can run only in process context. */ void usb_autopm_put_interface(struct usb_interface *intf) { struct usb_device *udev = interface_to_usbdev(intf); int status; usb_mark_last_busy(udev); atomic_dec(&intf->pm_usage_cnt); status = pm_runtime_put_sync(&intf->dev); dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", __func__, atomic_read(&intf->dev.power.usage_count), status); } EXPORT_SYMBOL_GPL(usb_autopm_put_interface); /** * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be decremented * * This routine does much the same thing as usb_autopm_put_interface(): * It decrements @intf's usage counter and schedules a delayed * autosuspend request if the counter is <= 0. The difference is that it * does not perform any synchronization; callers should hold a private * lock and handle all synchronization issues themselves. * * Typically a driver would call this routine during an URB's completion * handler, if no more URBs were pending. * * This routine can run in atomic context. */ void usb_autopm_put_interface_async(struct usb_interface *intf) { struct usb_device *udev = interface_to_usbdev(intf); int status; usb_mark_last_busy(udev); atomic_dec(&intf->pm_usage_cnt); status = pm_runtime_put(&intf->dev); dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", __func__, atomic_read(&intf->dev.power.usage_count), status); } EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async); /** * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be decremented * * This routine decrements @intf's usage counter but does not carry out an * autosuspend. * * This routine can run in atomic context. */ void usb_autopm_put_interface_no_suspend(struct usb_interface *intf) { struct usb_device *udev = interface_to_usbdev(intf); usb_mark_last_busy(udev); atomic_dec(&intf->pm_usage_cnt); pm_runtime_put_noidle(&intf->dev); } EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend); /** * usb_autopm_get_interface - increment a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be incremented * * This routine should be called by an interface driver when it wants to * use @intf and needs to guarantee that it is not suspended. In addition, * the routine prevents @intf from being autosuspended subsequently. (Note * that this will not prevent suspend events originating in the PM core.) * This prevention will persist until usb_autopm_put_interface() is called * or @intf is unbound. A typical example would be a character-device * driver when its device file is opened. * * @intf's usage counter is incremented to prevent subsequent autosuspends. * However if the autoresume fails then the counter is re-decremented. * * This routine can run only in process context. */ int usb_autopm_get_interface(struct usb_interface *intf) { int status; status = pm_runtime_get_sync(&intf->dev); if (status < 0) pm_runtime_put_sync(&intf->dev); else atomic_inc(&intf->pm_usage_cnt); dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", __func__, atomic_read(&intf->dev.power.usage_count), status); if (status > 0) status = 0; return status; } EXPORT_SYMBOL_GPL(usb_autopm_get_interface); /** * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be incremented * * This routine does much the same thing as * usb_autopm_get_interface(): It increments @intf's usage counter and * queues an autoresume request if the device is suspended. The * differences are that it does not perform any synchronization (callers * should hold a private lock and handle all synchronization issues * themselves), and it does not autoresume the device directly (it only * queues a request). After a successful call, the device may not yet be * resumed. * * This routine can run in atomic context. */ int usb_autopm_get_interface_async(struct usb_interface *intf) { int status; status = pm_runtime_get(&intf->dev); if (status < 0 && status != -EINPROGRESS) pm_runtime_put_noidle(&intf->dev); else atomic_inc(&intf->pm_usage_cnt); dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", __func__, atomic_read(&intf->dev.power.usage_count), status); if (status > 0 || status == -EINPROGRESS) status = 0; return status; } EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async); /** * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be incremented * * This routine increments @intf's usage counter but does not carry out an * autoresume. * * This routine can run in atomic context. */ void usb_autopm_get_interface_no_resume(struct usb_interface *intf) { struct usb_device *udev = interface_to_usbdev(intf); usb_mark_last_busy(udev); atomic_inc(&intf->pm_usage_cnt); pm_runtime_get_noresume(&intf->dev); } EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume); /* Internal routine to check whether we may autosuspend a device. */ static int autosuspend_check(struct usb_device *udev) { int w, i; struct usb_interface *intf; /* Fail if autosuspend is disabled, or any interfaces are in use, or * any interface drivers require remote wakeup but it isn't available. */ w = 0; if (udev->actconfig) { for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { intf = udev->actconfig->interface[i]; /* We don't need to check interfaces that are * disabled for runtime PM. Either they are unbound * or else their drivers don't support autosuspend * and so they are permanently active. */ if (intf->dev.power.disable_depth) continue; if (atomic_read(&intf->dev.power.usage_count) > 0) return -EBUSY; w |= intf->needs_remote_wakeup; /* Don't allow autosuspend if the device will need * a reset-resume and any of its interface drivers * doesn't include support or needs remote wakeup. */ if (udev->quirks & USB_QUIRK_RESET_RESUME) { struct usb_driver *driver; driver = to_usb_driver(intf->dev.driver); if (!driver->reset_resume || intf->needs_remote_wakeup) return -EOPNOTSUPP; } } } if (w && !device_can_wakeup(&udev->dev)) { dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n"); return -EOPNOTSUPP; } udev->do_remote_wakeup = w; return 0; } int usb_runtime_suspend(struct device *dev) { struct usb_device *udev = to_usb_device(dev); int status; /* A USB device can be suspended if it passes the various autosuspend * checks. Runtime suspend for a USB device means suspending all the * interfaces and then the device itself. */ if (autosuspend_check(udev) != 0) return -EAGAIN; status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND); /* Allow a retry if autosuspend failed temporarily */ if (status == -EAGAIN || status == -EBUSY) usb_mark_last_busy(udev); /* The PM core reacts badly unless the return code is 0, * -EAGAIN, or -EBUSY, so always return -EBUSY on an error. */ if (status != 0) return -EBUSY; return status; } int usb_runtime_resume(struct device *dev) { struct usb_device *udev = to_usb_device(dev); int status; /* Runtime resume for a USB device means resuming both the device * and all its interfaces. */ status = usb_resume_both(udev, PMSG_AUTO_RESUME); return status; } int usb_runtime_idle(struct device *dev) { struct usb_device *udev = to_usb_device(dev); /* An idle USB device can be suspended if it passes the various * autosuspend checks. */ if (autosuspend_check(udev) == 0) pm_runtime_autosuspend(dev); return 0; } int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable) { struct usb_hcd *hcd = bus_to_hcd(udev->bus); int ret = -EPERM; if (hcd->driver->set_usb2_hw_lpm) { ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable); if (!ret) udev->usb2_hw_lpm_enabled = enable; } return ret; } #endif /* CONFIG_USB_SUSPEND */ struct bus_type usb_bus_type = { .name = "usb", .match = usb_device_match, .uevent = usb_uevent, };