/*
* 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"
static int usb_match_one_id(struct usb_interface *interface,
const struct usb_device_id *id);
struct usb_dynid {
struct list_head node;
struct usb_device_id id;
};
#ifdef CONFIG_HOTPLUG
/*
* Adds a new dynamic USBdevice ID to this driver,
* and cause the driver to probe for all devices again.
*/
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);
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(&usb_drv->dynids.lock);
list_add_tail(&usb_drv->dynids.list, &dynid->node);
spin_unlock(&usb_drv->dynids.lock);
if (get_driver(driver)) {
retval = driver_attach(driver);
put_driver(driver);
}
if (retval)
return retval;
return 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, 1);
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, 1);
}
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, 1);
/* 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, 1);
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 and the driver model's usb_bus_type.subsys
* writelock. So driver probe() entries don't need extra locking,
* but other call contexts may need to explicitly claim those locks.
*/
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 and the driver model's usb_bus_type.subsys
* writelock. So driver disconnect() entries don't need extra locking,
* but other call contexts may need to explicitly claim those locks.
*/
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 */
static 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 ((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;
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;
}
/**
* 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 bDeviceClass).
*
* 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);
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.
*
* 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)
{
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;
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 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 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 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 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;
}
/**
* 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.
*/
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);
/* For autosuspend, fail fast if anything is in use.
* Also fail if any interfaces require remote wakeup but it
* isn't available. */
if (udev->auto_pm) {
if (udev->pm_usage_cnt > 0)
return -EBUSY;
if (udev->actconfig) {
for (; 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;
}
}
i = 0;
}
}
/* Suspend all the interfaces and then udev itself */
if (udev->actconfig) {
for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
intf = udev->actconfig->interface[i];
status = suspend_interface(intf, msg);
if (status != 0)
break;
}
}
if (status == 0)
status = 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];
resume_interface(intf);
}
/* If the suspend succeeded, propagate it up the tree */
} else if (parent)
usb_autosuspend_device(parent, 0);
// 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.
*/
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) {
usb_pm_lock(parent);
parent->auto_pm = 1;
status = usb_resume_both(parent);
} 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;
}
if (status == 0)
status = resume_device(udev);
if (parent)
usb_pm_unlock(parent);
} else {
/* Needed only for setting udev->dev.power.power_state.event
* and for possible debugging message. */
status = resume_device(udev);
}
/* Now the parent won't suspend until we are finished */
if (status == 0 && udev->actconfig) {
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
intf = udev->actconfig->interface[i];
resume_interface(intf);
}
}
// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
return status;
}
#ifdef CONFIG_USB_SUSPEND
/**
* usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
* @udev: the usb_device to autosuspend
* @dec_usage_cnt: flag to decrement @udev's PM-usage counter
*
* 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.
*
* @dec_usage_cnt should be 1 if the subsystem previously incremented
* @udev's usage counter (such as by passing 1 to usb_autoresume_device);
* otherwise it should be 0.
*
* If the usage counter for @udev or any of its active interfaces is greater
* than 0, the autosuspend request will not be queued. (If an interface
* driver does not support autosuspend then its usage counter is permanently
* positive.) Likewise, 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 dec_usage_cnt)
{
usb_pm_lock(udev);
udev->pm_usage_cnt -= dec_usage_cnt;
if (udev->pm_usage_cnt <= 0)
queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
USB_AUTOSUSPEND_DELAY);
usb_pm_unlock(udev);
// 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
* @inc_usage_cnt: flag to increment @udev's PM-usage counter
*
* This routine should be called when a core subsystem wants to use @udev
* and needs to guarantee that it is not suspended. In addition, the
* caller can prevent @udev from being autosuspended subsequently. (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 (autosuspend
* should be prevented until the file is closed) or when a remote-wakeup
* request is received (later autosuspends should not be prevented).
*
* @inc_usage_cnt should be 1 to increment @udev's usage counter and prevent
* autosuspends. This prevention will persist until the usage counter is
* decremented again (such as by passing 1 to usb_autosuspend_device).
* Otherwise @inc_usage_cnt should be 0 to leave the usage counter unchanged.
* Regardless, if the autoresume fails then the usage counter is not
* incremented.
*
* 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 inc_usage_cnt)
{
int status;
usb_pm_lock(udev);
udev->pm_usage_cnt += inc_usage_cnt;
udev->auto_pm = 1;
status = usb_resume_both(udev);
if (status != 0)
udev->pm_usage_cnt -= inc_usage_cnt;
usb_pm_unlock(udev);
// dev_dbg(&udev->dev, "%s: status %d cnt %d\n",
// __FUNCTION__, status, udev->pm_usage_cnt);
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)
{
struct usb_device *udev = interface_to_usbdev(intf);
usb_pm_lock(udev);
if (intf->condition != USB_INTERFACE_UNBOUND &&
--intf->pm_usage_cnt <= 0) {
queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
USB_AUTOSUSPEND_DELAY);
}
usb_pm_unlock(udev);
// dev_dbg(&intf->dev, "%s: cnt %d\n",
// __FUNCTION__, 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)
{
struct usb_device *udev = interface_to_usbdev(intf);
int status;
usb_pm_lock(udev);
if (intf->condition == USB_INTERFACE_UNBOUND)
status = -ENODEV;
else {
++intf->pm_usage_cnt;
udev->auto_pm = 1;
status = usb_resume_both(udev);
if (status != 0)
--intf->pm_usage_cnt;
}
usb_pm_unlock(udev);
// 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);
#endif /* CONFIG_USB_SUSPEND */
static int usb_suspend(struct device *dev, pm_message_t message)
{
int status;
if (is_usb_device(dev)) {
struct usb_device *udev = to_usb_device(dev);
usb_pm_lock(udev);
udev->auto_pm = 0;
status = usb_suspend_both(udev, message);
usb_pm_unlock(udev);
} else
status = 0;
return status;
}
static int usb_resume(struct device *dev)
{
int status;
if (is_usb_device(dev)) {
struct usb_device *udev = to_usb_device(dev);
usb_pm_lock(udev);
udev->auto_pm = 0;
status = usb_resume_both(udev);
usb_pm_unlock(udev);
/* Rebind drivers that had no suspend method? */
} else
status = 0;
return status;
}
#endif /* CONFIG_PM */
struct bus_type usb_bus_type = {
.name = "usb",
.match = usb_device_match,
.uevent = usb_uevent,
#ifdef CONFIG_PM
.suspend = usb_suspend,
.resume = usb_resume,
#endif
};
