diff options
Diffstat (limited to 'drivers/usb/core/driver.c')
| -rw-r--r-- | drivers/usb/core/driver.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 2b39583040d0..057eeab06004 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1415,6 +1415,48 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) #ifdef CONFIG_USB_SUSPEND +/** + * usb_enable_autosuspend - allow a USB device to be autosuspended + * @udev: the USB device which may be autosuspended + * + * This routine allows @udev to be autosuspended. An autosuspend won't + * take place until the autosuspend_delay has elapsed and all the other + * necessary conditions are satisfied. + * + * The caller must hold @udev's device lock. + */ +int usb_enable_autosuspend(struct usb_device *udev) +{ + if (udev->autosuspend_disabled) { + udev->autosuspend_disabled = 0; + usb_autosuspend_device(udev); + } + return 0; +} +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. + */ +int usb_disable_autosuspend(struct usb_device *udev) +{ + int rc = 0; + + if (!udev->autosuspend_disabled) { + rc = usb_autoresume_device(udev); + if (rc == 0) + udev->autosuspend_disabled = 1; + } + return rc; +} +EXPORT_SYMBOL_GPL(usb_disable_autosuspend); + /* Internal routine to adjust a device's usage counter and change * its autosuspend state. */ |