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| author | Alan Stern <stern@rowland.harvard.edu> | 2006-08-30 15:47:02 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2006-09-27 11:58:57 -0700 |
| commit | 645daaab0b6adc35c1838df2a82f9d729fdb1767 (patch) | |
| tree | 908d58f6c0ad01e9c1622a4c12c9c8080c629baa /drivers/usb/core/usb.c | |
| parent | b6956ffa595db97656d5901ca8fec77ef272d41a (diff) | |
| download | linux-645daaab0b6adc35c1838df2a82f9d729fdb1767.tar.bz2 | |
usbcore: add autosuspend/autoresume infrastructure
This patch (as739) adds the basic infrastructure for USB autosuspend
and autoresume. The main features are:
PM usage counters added to struct usb_device and struct
usb_interface, indicating whether it's okay to autosuspend
them or they are currently in use.
Flag added to usb_device indicating whether the current
suspend/resume operation originated from outside or as an
autosuspend/autoresume.
Flag added to usb_driver indicating whether the driver
supports autosuspend. If not, no device bound to the driver
will be autosuspended.
Mutex added to usb_device for protecting PM operations.
Unlike the device semaphore, the locking rule for the pm_mutex
is that you must acquire the locks going _up_ the device tree.
New routines handling autosuspend/autoresume requests for
interfaces and devices.
Suspend and resume requests are propagated up the device tree
(but not outside the USB subsystem).
work_struct added to usb_device, for carrying out delayed
autosuspend requests.
Autoresume added (and autosuspend prevented) during probe and
disconnect.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/core/usb.c')
| -rw-r--r-- | drivers/usb/core/usb.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index b0c0a993338f..6b029cdb8671 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -168,6 +168,10 @@ static void usb_release_dev(struct device *dev) udev = to_usb_device(dev); +#ifdef CONFIG_PM + cancel_delayed_work(&udev->autosuspend); + flush_scheduled_work(); +#endif usb_destroy_configuration(udev); usb_put_hcd(bus_to_hcd(udev->bus)); kfree(udev->product); @@ -176,6 +180,21 @@ static void usb_release_dev(struct device *dev) kfree(udev); } +#ifdef CONFIG_PM + +/* usb_autosuspend_work - callback routine to autosuspend a USB device */ +static void usb_autosuspend_work(void *_udev) +{ + struct usb_device *udev = _udev; + + mutex_lock_nested(&udev->pm_mutex, udev->level); + udev->auto_pm = 1; + usb_suspend_both(udev, PMSG_SUSPEND); + mutex_unlock(&udev->pm_mutex); +} + +#endif + /** * usb_alloc_dev - usb device constructor (usbcore-internal) * @parent: hub to which device is connected; null to allocate a root hub @@ -251,6 +270,10 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1) dev->parent = parent; INIT_LIST_HEAD(&dev->filelist); +#ifdef CONFIG_PM + mutex_init(&dev->pm_mutex); + INIT_WORK(&dev->autosuspend, usb_autosuspend_work, dev); +#endif return dev; } |