// SPDX-License-Identifier: GPL-2.0 /* * drivers/usb/core/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 * * Released under the GPLv2 only. * * 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. *
*/
/* * 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, conststruct usb_device_id *id_table, struct device_driver *driver, constchar *buf, size_t count)
{ struct usb_dynid *dynid;
u32 idVendor = 0;
u32 idProduct = 0; unsignedint bInterfaceClass = 0;
u32 refVendor, refProduct; int fields = 0; int retval = 0;
/* called from driver core with dev locked */ staticint 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 supports autosuspend.
*/ if (!udriver->supports_autosuspend)
error = usb_autoresume_device(udev); if (error) return error;
if (udriver->generic_subclass)
error = usb_generic_driver_probe(udev); if (error) return error;
/* Probe the USB device with the driver in hand, but only * defer to a generic driver in case the current USB * device driver has an id_table or a match function; i.e., * when the device driver was explicitly matched against * a device. * * If the device driver does not have either of these, * then we assume that it can bind to any device and is * not truly a more specialized/non-generic driver, so a * return value of -ENODEV should not force the device * to be handled by the generic USB driver, as there * can still be another, more specialized, device driver. * * This accommodates the usbip driver. * * TODO: What if, in the future, there are multiple * specialized USB device drivers for a particular device? * In such cases, there is a need to try all matching * specialised device drivers prior to setting the * use_generic_driver bit.
*/ if (udriver->probe)
error = udriver->probe(udev); elseif (!udriver->generic_subclass)
error = -EINVAL; if (error == -ENODEV && udriver != &usb_generic_driver &&
(udriver->id_table || udriver->match)) {
udev->use_generic_driver = 1; return -EPROBE_DEFER;
} return error;
}
/* called from driver core with dev locked */ staticint 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);
if (udriver->disconnect)
udriver->disconnect(udev); if (udriver->generic_subclass)
usb_generic_driver_disconnect(udev); if (!udriver->supports_autosuspend)
usb_autosuspend_device(udev); return 0;
}
/* called from driver core with dev locked */ staticint 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); conststruct usb_device_id *id; int error = -ENODEV; int lpm_disable_error = -ENODEV;
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;
} elseif (intf->authorized == 0) {
dev_err(&intf->dev, "Interface %d is not authorized for usage\n",
intf->altsetting->desc.bInterfaceNumber); return error;
}
id = usb_match_dynamic_id(intf, driver); if (!id)
id = usb_match_id(intf, driver->id_table); 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.
*/ if (driver->disable_hub_initiated_lpm) {
lpm_disable_error = usb_unlocked_disable_lpm(udev); if (lpm_disable_error) {
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);
/* 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 */ staticint 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_host_endpoint *ep, **eps = NULL; struct usb_device *udev; int i, j, error, r; int lpm_disable_error = -ENODEV;
/* If hub-initiated LPM policy may change, 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.
*/ if (driver->disable_hub_initiated_lpm)
lpm_disable_error = usb_unlocked_disable_lpm(udev);
/* * Terminate all URBs for this interface unless the driver * supports "soft" unbinding and the device is still present.
*/ if (!driver->soft_unbind || udev->state == USB_STATE_NOTATTACHED)
usb_disable_interface(udev, intf, false);
driver->disconnect(intf);
/* Free streams */ for (i = 0, j = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
ep = &intf->cur_altsetting->endpoint[i]; if (ep->streams == 0) continue; if (j == 0) {
eps = kmalloc_array(USB_MAXENDPOINTS, sizeof(void *),
GFP_KERNEL); if (!eps) break;
}
eps[j++] = ep;
} if (j) {
usb_free_streams(intf, eps, j, GFP_KERNEL);
kfree(eps);
}
/* 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);
} elseif (!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);
/* 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);
driver = to_usb_driver(dev->driver); if (driver->shutdown)
driver->shutdown(intf);
}
/** * 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 * @data: 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. * * 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. * * Return: 0 on success.
*/ int usb_driver_claim_interface(struct usb_driver *driver, struct usb_interface *iface, void *data)
{ struct device *dev; int retval = 0;
if (!iface) return -ENODEV;
dev = &iface->dev; if (dev->driver) return -EBUSY;
/* reject claim if interface is not authorized */ if (!iface->authorized) return -ENODEV;
/* 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);
/** * 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->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, conststruct 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, conststruct 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, conststruct 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);
/** * 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. * * Return: The first matching usb_device_id, or %NULL. * * 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.
*/ conststruct usb_device_id *usb_match_id(struct usb_interface *interface, conststruct 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;
}
/* If the device driver under consideration does not have a * id_table or a match function, then let the driver's probe * function decide.
*/ if (!udrv->id_table && !udrv->match) return 1;
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;
/** * 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. * * Return: 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 (!retval) {
pr_info("%s: registered new device driver %s\n",
usbcore_name, new_udriver->name); /* * Check whether any device could be better served with * this new driver
*/
bus_for_each_dev(&usb_bus_type, NULL, new_udriver,
__usb_bus_reprobe_drivers);
} else {
pr_err("%s: error %d registering device driver %s\n",
usbcore_name, retval, new_udriver->name);
}
/** * 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);
/** * 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. * * Return: 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, constchar *mod_name)
{ int retval = 0;
/** * 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);
/* 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 @intf's lock.
*/ void usb_forced_unbind_intf(struct usb_interface *intf)
{ struct usb_driver *driver = to_usb_driver(intf->dev.driver);
/* Mark the interface for later rebinding */
intf->needs_binding = 1;
}
/* * Unbind drivers for @udev's marked interfaces. These interfaces have * the needs_binding flag set, for example by usb_resume_interface(). * * The caller must hold @udev's device lock.
*/ staticvoid unbind_marked_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);
}
}
}
/* Delayed forced unbinding of a USB interface driver and scan * for rebinding. * * The caller must hold @intf's device's lock, but not @intf's lock. * * Note: Rebinds will be skipped if a system sleep transition is in * progress and the PM "complete" callback hasn't occurred yet.
*/ staticvoid 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 && rc != -EPROBE_DEFER)
dev_warn(&intf->dev, "rebind failed: %d\n", rc);
}
}
/* * Rebind drivers to @udev's marked interfaces. These interfaces have * the needs_binding flag set. * * The caller must hold @udev's device lock.
*/ staticvoid rebind_marked_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);
}
}
}
/* * Unbind all of @udev's marked interfaces and then rebind all of them. * This ordering is necessary because some drivers claim several interfaces * when they are first probed. * * The caller must hold @udev's device lock.
*/ void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev)
{
unbind_marked_interfaces(udev);
rebind_marked_interfaces(udev);
}
#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.
*/ staticvoid 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);
}
}
}
}
staticint 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;
} if (udriver->suspend)
status = udriver->suspend(udev, msg); if (status == 0 && udriver->generic_subclass)
status = usb_generic_driver_suspend(udev, msg);
done:
dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); return status;
}
staticint 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); if (udriver->generic_subclass)
status = usb_generic_driver_resume(udev, msg); if (status == 0 && udriver->resume)
status = udriver->resume(udev, msg);
done:
dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); return status;
}
staticint usb_suspend_interface(struct usb_device *udev, struct usb_interface *intf, pm_message_t msg)
{ struct usb_driver *driver; int status = 0;
/* 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;
}
staticint 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_dbg(&intf->dev, "no reset_resume for driver %s?\n",
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. When the routine is called in * autosuspend, 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, but when called from system sleep, all error * from suspend methods of interfaces and the non-root-hub device itself * are simply ignored, so all suspended interfaces are only resumed * to the device's state when @udev is root-hub and its suspend method * returns failure. * * 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. * * Return: 0 if the suspend succeeded.
*/ staticint 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 device is inaccessible, don't try to resume * suspended interfaces and just return the error.
*/ if (status && status != -EBUSY) { int err;
u16 devstat;
/* If the suspend failed, resume interfaces that did get suspended */ if (status != 0) { if (udev->actconfig) {
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 * 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. * * Return: 0 on success.
*/ staticint 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;
}
staticvoid choose_wakeup(struct usb_device *udev, pm_message_t msg)
{ int w;
/* * For FREEZE/QUIESCE, disable remote wakeups so no interrupts get * generated.
*/ if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
w = 0;
} else { /* * 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); int r;
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);
r = usb_suspend_both(udev, msg); if (r) return r;
if (udev->quirks & USB_QUIRK_DISCONNECT_SUSPEND)
usb_port_disable(udev);
return 0;
}
/* 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)
rebind_marked_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_marked_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;
}
/** * 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_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. * * Return: 0 on success. A negative error code otherwise.
*/ int usb_autoresume_device(struct usb_device *udev)
{ int status;
status = pm_runtime_resume_and_get(&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_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_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_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. * * Return: 0 on success.
*/ int usb_autopm_get_interface(struct usb_interface *intf)
{ int status;
status = pm_runtime_resume_and_get(&intf->dev);
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. * * Return: 0 on success. A negative error code otherwise.
*/ 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);
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);
/* Internal routine to check whether we may autosuspend a device. */ staticint autosuspend_check(struct usb_device *udev)
{ int w, i; struct usb_interface *intf;
if (udev->state == USB_STATE_NOTATTACHED) return -ENODEV;
/* 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;
}
/* * If the device is a direct child of the root hub and the HCD * doesn't handle wakeup requests, don't allow autosuspend when * wakeup is needed.
*/ if (w && udev->parent == udev->bus->root_hub &&
bus_to_hcd(udev->bus)->cant_recv_wakeups) {
dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\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 * (except for root hubs, because they don't suspend through * an upstream port like other USB devices).
*/ if (status != 0 && udev->parent) 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); /* Tell the core not to suspend it, though. */ return -EBUSY;
}
staticint 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;
}
int usb_enable_usb2_hardware_lpm(struct usb_device *udev)
{ if (!udev->usb2_hw_lpm_capable ||
!udev->usb2_hw_lpm_allowed ||
udev->usb2_hw_lpm_enabled) return 0;
return usb_set_usb2_hardware_lpm(udev, 1);
}
int usb_disable_usb2_hardware_lpm(struct usb_device *udev)
{ if (!udev->usb2_hw_lpm_enabled) return 0;
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