| /* |
| * drivers/usb/driver.c - most of the driver model stuff for usb |
| * |
| * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de> |
| * |
| * 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 <linux/device.h> |
| #include <linux/usb.h> |
| #include <linux/workqueue.h> |
| #include "hcd.h" |
| #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; |
| int fields = 0; |
| int retval = 0; |
| |
| fields = sscanf(buf, "%x %x", &idVendor, &idProduct); |
| 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; |
| |
| spin_lock(&dynids->lock); |
| list_add_tail(&dynids->list, &dynid->node); |
| spin_unlock(&dynids->lock); |
| |
| if (get_driver(driver)) { |
| retval = driver_attach(driver); |
| put_driver(driver); |
| } |
| |
| if (retval) |
| return retval; |
| return count; |
| } |
| EXPORT_SYMBOL_GPL(usb_store_new_id); |
| |
| 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_IWUSR, NULL, store_new_id); |
| |
| static int usb_create_newid_file(struct usb_driver *usb_drv) |
| { |
| int error = 0; |
| |
| if (usb_drv->no_dynamic_id) |
| goto exit; |
| |
| if (usb_drv->probe != NULL) |
| error = sysfs_create_file(&usb_drv->drvwrap.driver.kobj, |
| &driver_attr_new_id.attr); |
| exit: |
| return error; |
| } |
| |
| static void usb_remove_newid_file(struct usb_driver *usb_drv) |
| { |
| if (usb_drv->no_dynamic_id) |
| return; |
| |
| if (usb_drv->probe != NULL) |
| sysfs_remove_file(&usb_drv->drvwrap.driver.kobj, |
| &driver_attr_new_id.attr); |
| } |
| |
| 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_file(struct usb_driver *usb_drv) |
| { |
| return 0; |
| } |
| |
| static void usb_remove_newid_file(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; |
| int error = -ENODEV; |
| |
| dev_dbg(dev, "%s\n", __FUNCTION__); |
| |
| if (!is_usb_device(dev)) /* Sanity check */ |
| return error; |
| |
| udev = to_usb_device(dev); |
| |
| /* TODO: Add real matching code */ |
| |
| /* The device should always appear to be in use |
| * unless the driver suports autosuspend. |
| */ |
| udev->pm_usage_cnt = !(udriver->supports_autosuspend); |
| |
| error = udriver->probe(udev); |
| return error; |
| } |
| |
| /* called from driver core with dev locked */ |
| static int usb_unbind_device(struct device *dev) |
| { |
| struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); |
| |
| udriver->disconnect(to_usb_device(dev)); |
| return 0; |
| } |
| |
| |
| /* 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; |
| struct usb_device *udev; |
| const struct usb_device_id *id; |
| int error = -ENODEV; |
| |
| dev_dbg(dev, "%s\n", __FUNCTION__); |
| |
| if (is_usb_device(dev)) /* Sanity check */ |
| return error; |
| |
| intf = to_usb_interface(dev); |
| udev = interface_to_usbdev(intf); |
| |
| id = usb_match_id(intf, driver->id_table); |
| if (!id) |
| id = usb_match_dynamic_id(intf, driver); |
| if (id) { |
| dev_dbg(dev, "%s - got id\n", __FUNCTION__); |
| |
| error = usb_autoresume_device(udev); |
| if (error) |
| return error; |
| |
| /* Interface "power state" doesn't correspond to any hardware |
| * state whatsoever. We use it to record when it's bound to |
| * a driver that may start I/0: it's not frozen/quiesced. |
| */ |
| mark_active(intf); |
| intf->condition = USB_INTERFACE_BINDING; |
| |
| /* The interface should always appear to be in use |
| * unless the driver suports autosuspend. |
| */ |
| intf->pm_usage_cnt = !(driver->supports_autosuspend); |
| |
| error = driver->probe(intf, id); |
| if (error) { |
| mark_quiesced(intf); |
| intf->needs_remote_wakeup = 0; |
| intf->condition = USB_INTERFACE_UNBOUND; |
| } else |
| intf->condition = USB_INTERFACE_BOUND; |
| |
| 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; |
| |
| intf->condition = USB_INTERFACE_UNBINDING; |
| |
| /* Autoresume for set_interface call below */ |
| udev = interface_to_usbdev(intf); |
| error = usb_autoresume_device(udev); |
| |
| /* release all urbs for this interface */ |
| usb_disable_interface(interface_to_usbdev(intf), intf); |
| |
| driver->disconnect(intf); |
| |
| /* reset other interface state */ |
| usb_set_interface(interface_to_usbdev(intf), |
| intf->altsetting[0].desc.bInterfaceNumber, |
| 0); |
| usb_set_intfdata(intf, NULL); |
| |
| intf->condition = USB_INTERFACE_UNBOUND; |
| mark_quiesced(intf); |
| intf->needs_remote_wakeup = 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 = interface_to_usbdev(iface); |
| int retval = 0; |
| |
| if (dev->driver) |
| return -EBUSY; |
| |
| dev->driver = &driver->drvwrap.driver; |
| usb_set_intfdata(iface, priv); |
| |
| usb_pm_lock(udev); |
| iface->condition = USB_INTERFACE_BOUND; |
| mark_active(iface); |
| iface->pm_usage_cnt = !(driver->supports_autosuspend); |
| usb_pm_unlock(udev); |
| |
| /* 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); |
| |
| return retval; |
| } |
| EXPORT_SYMBOL(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; |
| struct usb_device *udev = interface_to_usbdev(iface); |
| |
| /* 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; |
| |
| /* don't release if the interface hasn't been added yet */ |
| if (device_is_registered(dev)) { |
| iface->condition = USB_INTERFACE_UNBINDING; |
| device_release_driver(dev); |
| } |
| |
| dev->driver = NULL; |
| usb_set_intfdata(iface, NULL); |
| |
| usb_pm_lock(udev); |
| iface->condition = USB_INTERFACE_UNBOUND; |
| mark_quiesced(iface); |
| iface->needs_remote_wakeup = 0; |
| usb_pm_unlock(udev); |
| } |
| EXPORT_SYMBOL(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(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; |
| |
| /* The interface class, subclass, and protocol 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))) |
| 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; |
| |
| return 1; |
| } |
| 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->bDeviceClass || id->bInterfaceClass || |
| id->driver_info; id++) { |
| if (usb_match_one_id(interface, id)) |
| return id; |
| } |
| |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL_FUTURE(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 { |
| 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 |
| |
| /* |
| * This sends an uevent to userspace, typically helping to load driver |
| * or other modules, configure the device, and more. Drivers can provide |
| * a MODULE_DEVICE_TABLE to help with module loading subtasks. |
| * |
| * We're called either from khubd (the typical case) or from root hub |
| * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle |
| * delays in event delivery. Use sysfs (and DEVPATH) to make sure the |
| * device (and this configuration!) are still present. |
| */ |
| static int usb_uevent(struct device *dev, char **envp, int num_envp, |
| char *buffer, int buffer_size) |
| { |
| struct usb_interface *intf; |
| struct usb_device *usb_dev; |
| struct usb_host_interface *alt; |
| int i = 0; |
| int length = 0; |
| |
| if (!dev) |
| return -ENODEV; |
| |
| /* driver is often null here; dev_dbg() would oops */ |
| pr_debug ("usb %s: uevent\n", dev->bus_id); |
| |
| if (is_usb_device(dev)) { |
| usb_dev = to_usb_device(dev); |
| alt = NULL; |
| } else { |
| intf = to_usb_interface(dev); |
| usb_dev = interface_to_usbdev(intf); |
| alt = intf->cur_altsetting; |
| } |
| |
| if (usb_dev->devnum < 0) { |
| pr_debug ("usb %s: already deleted?\n", dev->bus_id); |
| return -ENODEV; |
| } |
| if (!usb_dev->bus) { |
| pr_debug ("usb %s: bus removed?\n", dev->bus_id); |
| return -ENODEV; |
| } |
| |
| #ifdef CONFIG_USB_DEVICEFS |
| /* If this is available, userspace programs can directly read |
| * all the device descriptors we don't tell them about. Or |
| * even act as usermode drivers. |
| * |
| * FIXME reduce hardwired intelligence here |
| */ |
| if (add_uevent_var(envp, num_envp, &i, |
| buffer, buffer_size, &length, |
| "DEVICE=/proc/bus/usb/%03d/%03d", |
| usb_dev->bus->busnum, usb_dev->devnum)) |
| return -ENOMEM; |
| #endif |
| |
| /* per-device configurations are common */ |
| if (add_uevent_var(envp, num_envp, &i, |
| buffer, buffer_size, &length, |
| "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(envp, num_envp, &i, |
| buffer, buffer_size, &length, |
| "TYPE=%d/%d/%d", |
| usb_dev->descriptor.bDeviceClass, |
| usb_dev->descriptor.bDeviceSubClass, |
| usb_dev->descriptor.bDeviceProtocol)) |
| return -ENOMEM; |
| |
| if (!is_usb_device(dev)) { |
| |
| if (add_uevent_var(envp, num_envp, &i, |
| buffer, buffer_size, &length, |
| "INTERFACE=%d/%d/%d", |
| alt->desc.bInterfaceClass, |
| alt->desc.bInterfaceSubClass, |
| alt->desc.bInterfaceProtocol)) |
| return -ENOMEM; |
| |
| if (add_uevent_var(envp, num_envp, &i, |
| buffer, buffer_size, &length, |
| "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X", |
| le16_to_cpu(usb_dev->descriptor.idVendor), |
| le16_to_cpu(usb_dev->descriptor.idProduct), |
| le16_to_cpu(usb_dev->descriptor.bcdDevice), |
| usb_dev->descriptor.bDeviceClass, |
| usb_dev->descriptor.bDeviceSubClass, |
| usb_dev->descriptor.bDeviceProtocol, |
| alt->desc.bInterfaceClass, |
| alt->desc.bInterfaceSubClass, |
| alt->desc.bInterfaceProtocol)) |
| return -ENOMEM; |
| } |
| |
| envp[i] = NULL; |
| |
| return 0; |
| } |
| |
| #else |
| |
| static int usb_uevent(struct device *dev, char **envp, |
| int num_envp, char *buffer, int buffer_size) |
| { |
| 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); |
| usbfs_update_special(); |
| } 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); |
| usbfs_update_special(); |
| } |
| 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) { |
| pr_info("%s: registered new interface driver %s\n", |
| usbcore_name, new_driver->name); |
| usbfs_update_special(); |
| usb_create_newid_file(new_driver); |
| } else { |
| printk(KERN_ERR "%s: error %d registering interface " |
| " driver %s\n", |
| usbcore_name, retval, new_driver->name); |
| } |
| |
| return retval; |
| } |
| EXPORT_SYMBOL_GPL_FUTURE(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_file(driver); |
| usb_free_dynids(driver); |
| driver_unregister(&driver->drvwrap.driver); |
| |
| usbfs_update_special(); |
| } |
| EXPORT_SYMBOL_GPL_FUTURE(usb_deregister); |
| |
| #ifdef CONFIG_PM |
| |
| /* Caller has locked udev's pm_mutex */ |
| 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 standard suspend. */ |
| if (udev->dev.driver == NULL) { |
| udev->do_remote_wakeup = 0; |
| status = usb_port_suspend(udev); |
| goto done; |
| } |
| |
| udriver = to_usb_device_driver(udev->dev.driver); |
| status = udriver->suspend(udev, msg); |
| |
| done: |
| // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status); |
| if (status == 0) |
| udev->dev.power.power_state.event = msg.event; |
| return status; |
| } |
| |
| /* Caller has locked udev's pm_mutex */ |
| static int usb_resume_device(struct usb_device *udev) |
| { |
| struct usb_device_driver *udriver; |
| int status = 0; |
| |
| if (udev->state == USB_STATE_NOTATTACHED || |
| udev->state != USB_STATE_SUSPENDED) |
| goto done; |
| |
| /* Can't resume it if it doesn't have a driver. */ |
| if (udev->dev.driver == NULL) { |
| status = -ENOTCONN; |
| goto done; |
| } |
| |
| udriver = to_usb_device_driver(udev->dev.driver); |
| status = udriver->resume(udev); |
| |
| done: |
| // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status); |
| if (status == 0) |
| udev->dev.power.power_state.event = PM_EVENT_ON; |
| return status; |
| } |
| |
| /* Caller has locked intf's usb_device's pm mutex */ |
| static int usb_suspend_interface(struct usb_interface *intf, pm_message_t msg) |
| { |
| struct usb_driver *driver; |
| int status = 0; |
| |
| /* with no hardware, USB interfaces only use FREEZE and ON states */ |
| if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED || |
| !is_active(intf)) |
| goto done; |
| |
| if (intf->condition == USB_INTERFACE_UNBOUND) /* This can't happen */ |
| goto done; |
| driver = to_usb_driver(intf->dev.driver); |
| |
| if (driver->suspend && driver->resume) { |
| status = driver->suspend(intf, msg); |
| if (status == 0) |
| mark_quiesced(intf); |
| else if (!interface_to_usbdev(intf)->auto_pm) |
| dev_err(&intf->dev, "%s error %d\n", |
| "suspend", status); |
| } else { |
| // FIXME else if there's no suspend method, disconnect... |
| // Not possible if auto_pm is set... |
| dev_warn(&intf->dev, "no suspend for driver %s?\n", |
| driver->name); |
| mark_quiesced(intf); |
| } |
| |
| done: |
| // dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status); |
| if (status == 0) |
| intf->dev.power.power_state.event = msg.event; |
| return status; |
| } |
| |
| /* Caller has locked intf's usb_device's pm_mutex */ |
| static int usb_resume_interface(struct usb_interface *intf) |
| { |
| struct usb_driver *driver; |
| int status = 0; |
| |
| if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED || |
| is_active(intf)) |
| 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) { |
| status = -ENOTCONN; |
| goto done; |
| } |
| driver = to_usb_driver(intf->dev.driver); |
| |
| if (driver->resume) { |
| status = driver->resume(intf); |
| if (status) |
| dev_err(&intf->dev, "%s error %d\n", |
| "resume", status); |
| else |
| mark_active(intf); |
| } else { |
| dev_warn(&intf->dev, "no resume for driver %s?\n", |
| driver->name); |
| mark_active(intf); |
| } |
| |
| done: |
| // dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status); |
| if (status == 0) |
| intf->dev.power.power_state.event = PM_EVENT_ON; |
| return status; |
| } |
| |
| #ifdef CONFIG_USB_SUSPEND |
| |
| /* Internal routine to check whether we may autosuspend a device. */ |
| static int autosuspend_check(struct usb_device *udev) |
| { |
| int i; |
| struct usb_interface *intf; |
| |
| /* For autosuspend, fail fast if anything is in use or autosuspend |
| * is disabled. Also fail if any interfaces require remote wakeup |
| * but it isn't available. |
| */ |
| udev->do_remote_wakeup = device_may_wakeup(&udev->dev); |
| if (udev->pm_usage_cnt > 0) |
| return -EBUSY; |
| if (!udev->autosuspend_delay) |
| return -EPERM; |
| |
| if (udev->actconfig) { |
| for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { |
| intf = udev->actconfig->interface[i]; |
| if (!is_active(intf)) |
| continue; |
| if (intf->pm_usage_cnt > 0) |
| return -EBUSY; |
| if (intf->needs_remote_wakeup && |
| !udev->do_remote_wakeup) { |
| dev_dbg(&udev->dev, "remote wakeup needed " |
| "for autosuspend\n"); |
| return -EOPNOTSUPP; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| #else |
| |
| #define autosuspend_check(udev) 0 |
| |
| #endif /* CONFIG_USB_SUSPEND */ |
| |
| /** |
| * 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. |
| * |
| * If an autosuspend is in progress (@udev->auto_pm is set), the routine |
| * checks first to make sure that neither the device itself or any of its |
| * active interfaces is in use (pm_usage_cnt is greater than 0). If they |
| * are, the autosuspend fails. |
| * |
| * If the suspend succeeds, the routine recursively queues an autosuspend |
| * request for @udev's parent device, thereby propagating the change up |
| * the device tree. If all of the parent's children are now suspended, |
| * the parent will autosuspend in turn. |
| * |
| * The suspend method calls are subject to mutual exclusion under control |
| * of @udev's pm_mutex. Many of these calls are also under the protection |
| * of @udev's device lock (including all requests originating outside the |
| * USB subsystem), but autosuspend requests generated by a child device or |
| * interface driver may not be. Usbcore will insure that the method calls |
| * do not arrive during bind, unbind, or reset operations. However, drivers |
| * must be prepared to handle suspend calls arriving at unpredictable times. |
| * The only way to block such calls is to do an autoresume (preventing |
| * autosuspends) while holding @udev's device lock (preventing outside |
| * suspends). |
| * |
| * The caller must hold @udev->pm_mutex. |
| * |
| * 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; |
| struct usb_interface *intf; |
| struct usb_device *parent = udev->parent; |
| |
| cancel_delayed_work(&udev->autosuspend); |
| if (udev->state == USB_STATE_NOTATTACHED) |
| return 0; |
| if (udev->state == USB_STATE_SUSPENDED) |
| return 0; |
| |
| udev->do_remote_wakeup = device_may_wakeup(&udev->dev); |
| |
| if (udev->auto_pm) { |
| status = autosuspend_check(udev); |
| if (status < 0) |
| return status; |
| } |
| |
| /* Suspend all the interfaces and then udev itself */ |
| if (udev->actconfig) { |
| for (; i < udev->actconfig->desc.bNumInterfaces; i++) { |
| intf = udev->actconfig->interface[i]; |
| status = usb_suspend_interface(intf, msg); |
| if (status != 0) |
| break; |
| } |
| } |
| if (status == 0) |
| status = usb_suspend_device(udev, msg); |
| |
| /* If the suspend failed, resume interfaces that did get suspended */ |
| if (status != 0) { |
| while (--i >= 0) { |
| intf = udev->actconfig->interface[i]; |
| usb_resume_interface(intf); |
| } |
| |
| /* If the suspend succeeded, propagate it up the tree */ |
| } else if (parent) |
| usb_autosuspend_device(parent); |
| |
| // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status); |
| return status; |
| } |
| |
| /** |
| * usb_resume_both - resume a USB device and its interfaces |
| * @udev: the usb_device to resume |
| * |
| * 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. |
| * |
| * Before starting the resume, the routine calls itself recursively for |
| * the parent device of @udev, thereby propagating the change up the device |
| * tree and assuring that @udev will be able to resume. If the parent is |
| * unable to resume successfully, the routine fails. |
| * |
| * The resume method calls are subject to mutual exclusion under control |
| * of @udev's pm_mutex. Many of these calls are also under the protection |
| * of @udev's device lock (including all requests originating outside the |
| * USB subsystem), but autoresume requests generated by a child device or |
| * interface driver may not be. Usbcore will insure that the method calls |
| * do not arrive during bind, unbind, or reset operations. However, drivers |
| * must be prepared to handle resume calls arriving at unpredictable times. |
| * The only way to block such calls is to do an autoresume (preventing |
| * other autoresumes) while holding @udev's device lock (preventing outside |
| * resumes). |
| * |
| * The caller must hold @udev->pm_mutex. |
| * |
| * This routine can run only in process context. |
| */ |
| static int usb_resume_both(struct usb_device *udev) |
| { |
| int status = 0; |
| int i; |
| struct usb_interface *intf; |
| struct usb_device *parent = udev->parent; |
| |
| cancel_delayed_work(&udev->autosuspend); |
| if (udev->state == USB_STATE_NOTATTACHED) |
| return -ENODEV; |
| |
| /* Propagate the resume up the tree, if necessary */ |
| if (udev->state == USB_STATE_SUSPENDED) { |
| if (parent) { |
| status = usb_autoresume_device(parent); |
| if (status == 0) { |
| status = usb_resume_device(udev); |
| if (status) { |
| usb_autosuspend_device(parent); |
| |
| /* It's possible usb_resume_device() |
| * failed after the port was |
| * unsuspended, causing udev to be |
| * logically disconnected. We don't |
| * want usb_disconnect() to autosuspend |
| * the parent again, so tell it that |
| * udev disconnected while still |
| * suspended. */ |
| if (udev->state == |
| USB_STATE_NOTATTACHED) |
| udev->discon_suspended = 1; |
| } |
| } |
| } else { |
| |
| /* We can't progagate beyond the USB subsystem, |
| * so if a root hub's controller is suspended |
| * then we're stuck. */ |
| if (udev->dev.parent->power.power_state.event != |
| PM_EVENT_ON) |
| status = -EHOSTUNREACH; |
| else |
| status = usb_resume_device(udev); |
| } |
| } else { |
| |
| /* Needed only for setting udev->dev.power.power_state.event |
| * and for possible debugging message. */ |
| status = usb_resume_device(udev); |
| } |
| |
| if (status == 0 && udev->actconfig) { |
| for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { |
| intf = udev->actconfig->interface[i]; |
| usb_resume_interface(intf); |
| } |
| } |
| |
| // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status); |
| return status; |
| } |
| |
| #ifdef CONFIG_USB_SUSPEND |
| |
| /* usb_autosuspend_work - callback routine to autosuspend a USB device */ |
| void usb_autosuspend_work(struct work_struct *work) |
| { |
| struct usb_device *udev = |
| container_of(work, struct usb_device, autosuspend.work); |
| |
| usb_pm_lock(udev); |
| udev->auto_pm = 1; |
| usb_suspend_both(udev, PMSG_SUSPEND); |
| usb_pm_unlock(udev); |
| } |
| |
| /* Internal routine to adjust a device's usage counter and change |
| * its autosuspend state. |
| */ |
| static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt) |
| { |
| int status = 0; |
| |
| usb_pm_lock(udev); |
| udev->pm_usage_cnt += inc_usage_cnt; |
| WARN_ON(udev->pm_usage_cnt < 0); |
| if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) { |
| udev->auto_pm = 1; |
| status = usb_resume_both(udev); |
| if (status != 0) |
| udev->pm_usage_cnt -= inc_usage_cnt; |
| } else if (inc_usage_cnt <= 0 && autosuspend_check(udev) == 0) |
| queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, |
| udev->autosuspend_delay); |
| usb_pm_unlock(udev); |
| return status; |
| } |
| |
| /** |
| * 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 or any of the usage counters |
| * for an active interface is greater than 0, no autosuspend request will be |
| * queued. (If an interface driver does not support autosuspend then its |
| * usage counter is permanently positive.) Furthermore, if an interface |
| * driver requires remote-wakeup capability during autosuspend but remote |
| * wakeup is disabled, the autosuspend will fail. |
| * |
| * Often the caller will hold @udev's device lock, but this is not |
| * necessary. |
| * |
| * This routine can run only in process context. |
| */ |
| void usb_autosuspend_device(struct usb_device *udev) |
| { |
| int status; |
| |
| status = usb_autopm_do_device(udev, -1); |
| // dev_dbg(&udev->dev, "%s: cnt %d\n", |
| // __FUNCTION__, udev->pm_usage_cnt); |
| } |
| |
| /** |
| * usb_try_autosuspend_device - attempt an autosuspend of a USB device and its interfaces |
| * @udev: the usb_device to autosuspend |
| * |
| * This routine should be called when a core subsystem thinks @udev may |
| * be ready to autosuspend. |
| * |
| * @udev's usage counter left unchanged. If it or any of the usage counters |
| * for an active interface is greater than 0, or autosuspend is not allowed |
| * for any other reason, no autosuspend request will be queued. |
| * |
| * This routine can run only in process context. |
| */ |
| void usb_try_autosuspend_device(struct usb_device *udev) |
| { |
| usb_autopm_do_device(udev, 0); |
| // dev_dbg(&udev->dev, "%s: cnt %d\n", |
| // __FUNCTION__, udev->pm_usage_cnt); |
| } |
| |
| /** |
| * 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. |
| * |
| * Often the caller will hold @udev's device lock, but this is not |
| * necessary (and attempting it might cause deadlock). |
| * |
| * This routine can run only in process context. |
| */ |
| int usb_autoresume_device(struct usb_device *udev) |
| { |
| int status; |
| |
| status = usb_autopm_do_device(udev, 1); |
| // dev_dbg(&udev->dev, "%s: status %d cnt %d\n", |
| // __FUNCTION__, status, udev->pm_usage_cnt); |
| return status; |
| } |
| |
| /* Internal routine to adjust an interface's usage counter and change |
| * its device's autosuspend state. |
| */ |
| static int usb_autopm_do_interface(struct usb_interface *intf, |
| int inc_usage_cnt) |
| { |
| struct usb_device *udev = interface_to_usbdev(intf); |
| int status = 0; |
| |
| usb_pm_lock(udev); |
| if (intf->condition == USB_INTERFACE_UNBOUND) |
| status = -ENODEV; |
| else { |
| intf->pm_usage_cnt += inc_usage_cnt; |
| if (inc_usage_cnt >= 0 && intf->pm_usage_cnt > 0) { |
| udev->auto_pm = 1; |
| status = usb_resume_both(udev); |
| if (status != 0) |
| intf->pm_usage_cnt -= inc_usage_cnt; |
| } else if (inc_usage_cnt <= 0 && autosuspend_check(udev) == 0) |
| queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, |
| udev->autosuspend_delay); |
| } |
| usb_pm_unlock(udev); |
| 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 queued. When |
| * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all |
| * the other usage counters for the sibling interfaces and @intf's |
| * usb_device, the device and all its interfaces will be autosuspended. |
| * |
| * Note that @intf->pm_usage_cnt is owned by the interface driver. The |
| * core will not change its value other than the increment and decrement |
| * in usb_autopm_get_interface and usb_autopm_put_interface. The driver |
| * may use this simple counter-oriented discipline or may set the value |
| * any way it likes. |
| * |
| * If the driver has set @intf->needs_remote_wakeup then autosuspend will |
| * take place only if the device's remote-wakeup facility is enabled. |
| * |
| * Suspend method calls queued by this routine can arrive at any time |
| * while @intf is resumed and its usage counter is equal to 0. They are |
| * not protected by the usb_device's lock but only by its pm_mutex. |
| * Drivers must provide their own synchronization. |
| * |
| * This routine can run only in process context. |
| */ |
| void usb_autopm_put_interface(struct usb_interface *intf) |
| { |
| int status; |
| |
| status = usb_autopm_do_interface(intf, -1); |
| // dev_dbg(&intf->dev, "%s: status %d cnt %d\n", |
| // __FUNCTION__, status, intf->pm_usage_cnt); |
| } |
| EXPORT_SYMBOL_GPL(usb_autopm_put_interface); |
| |
| /** |
| * 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. |
| * |
| * The routine increments @intf's usage counter. So long as the counter |
| * is greater than 0, autosuspend will not be allowed for @intf or its |
| * usb_device. When the driver is finished using @intf it should call |
| * usb_autopm_put_interface() to decrement the usage counter and queue |
| * a delayed autosuspend request (if the counter is <= 0). |
| * |
| * Note that @intf->pm_usage_cnt is owned by the interface driver. The |
| * core will not change its value other than the increment and decrement |
| * in usb_autopm_get_interface and usb_autopm_put_interface. The driver |
| * may use this simple counter-oriented discipline or may set the value |
| * any way it likes. |
| * |
| * Resume method calls generated by this routine can arrive at any time |
| * while @intf is suspended. They are not protected by the usb_device's |
| * lock but only by its pm_mutex. Drivers must provide their own |
| * synchronization. |
| * |
| * This routine can run only in process context. |
| */ |
| int usb_autopm_get_interface(struct usb_interface *intf) |
| { |
| int status; |
| |
| status = usb_autopm_do_interface(intf, 1); |
| // dev_dbg(&intf->dev, "%s: status %d cnt %d\n", |
| // __FUNCTION__, status, intf->pm_usage_cnt); |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(usb_autopm_get_interface); |
| |
| /** |
| * usb_autopm_set_interface - set a USB interface's autosuspend state |
| * @intf: the usb_interface whose state should be set |
| * |
| * This routine sets the autosuspend state of @intf's device according |
| * to @intf's usage counter, which the caller must have set previously. |
| * If the counter is <= 0, the device is autosuspended (if it isn't |
| * already suspended and if nothing else prevents the autosuspend). If |
| * the counter is > 0, the device is autoresumed (if it isn't already |
| * awake). |
| */ |
| int usb_autopm_set_interface(struct usb_interface *intf) |
| { |
| int status; |
| |
| status = usb_autopm_do_interface(intf, 0); |
| // dev_dbg(&intf->dev, "%s: status %d cnt %d\n", |
| // __FUNCTION__, status, intf->pm_usage_cnt); |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(usb_autopm_set_interface); |
| |
| #else |
| |
| void usb_autosuspend_work(struct work_struct *work) |
| {} |
| |
| #endif /* CONFIG_USB_SUSPEND */ |
| |
| /** |
| * usb_external_suspend_device - external suspend of a USB device and its interfaces |
| * @udev: the usb_device to suspend |
| * @msg: Power Management message describing this state transition |
| * |
| * This routine handles external suspend requests: ones not generated |
| * internally by a USB driver (autosuspend) but rather coming from the user |
| * (via sysfs) or the PM core (system sleep). The suspend will be carried |
| * out regardless of @udev's usage counter or those of its interfaces, |
| * and regardless of whether or not remote wakeup is enabled. Of course, |
| * interface drivers still have the option of failing the suspend (if |
| * there are unsuspended children, for example). |
| * |
| * The caller must hold @udev's device lock. |
| */ |
| int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg) |
| { |
| int status; |
| |
| usb_pm_lock(udev); |
| udev->auto_pm = 0; |
| status = usb_suspend_both(udev, msg); |
| usb_pm_unlock(udev); |
| return status; |
| } |
| |
| /** |
| * usb_external_resume_device - external resume of a USB device and its interfaces |
| * @udev: the usb_device to resume |
| * |
| * This routine handles external resume requests: ones not generated |
| * internally by a USB driver (autoresume) but rather coming from the user |
| * (via sysfs), the PM core (system resume), or the device itself (remote |
| * wakeup). @udev's usage counter is unaffected. |
| * |
| * The caller must hold @udev's device lock. |
| */ |
| int usb_external_resume_device(struct usb_device *udev) |
| { |
| int status; |
| |
| usb_pm_lock(udev); |
| udev->auto_pm = 0; |
| status = usb_resume_both(udev); |
| usb_pm_unlock(udev); |
| |
| /* Now that the device is awake, we can start trying to autosuspend |
| * it again. */ |
| if (status == 0) |
| usb_try_autosuspend_device(udev); |
| return status; |
| } |
| |
| static int usb_suspend(struct device *dev, pm_message_t message) |
| { |
| if (!is_usb_device(dev)) /* Ignore PM for interfaces */ |
| return 0; |
| return usb_external_suspend_device(to_usb_device(dev), message); |
| } |
| |
| static int usb_resume(struct device *dev) |
| { |
| if (!is_usb_device(dev)) /* Ignore PM for interfaces */ |
| return 0; |
| return usb_external_resume_device(to_usb_device(dev)); |
| } |
| |
| #else |
| |
| #define usb_suspend NULL |
| #define usb_resume NULL |
| |
| #endif /* CONFIG_PM */ |
| |
| struct bus_type usb_bus_type = { |
| .name = "usb", |
| .match = usb_device_match, |
| .uevent = usb_uevent, |
| .suspend = usb_suspend, |
| .resume = usb_resume, |
| }; |