diff options
Diffstat (limited to 'drivers/usb/core/driver.c')
| -rw-r--r-- | drivers/usb/core/driver.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 8c081308b0e..23b3c7e79d4 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1341,6 +1341,19 @@ void usb_autosuspend_work(struct work_struct *work) usb_autopm_do_device(udev, 0); } +/* usb_autoresume_work - callback routine to autoresume a USB device */ +void usb_autoresume_work(struct work_struct *work) +{ + struct usb_device *udev = + container_of(work, struct usb_device, autoresume); + + /* Wake it up, let the drivers do their thing, and then put it + * back to sleep. + */ + if (usb_autopm_do_device(udev, 1) == 0) + usb_autopm_do_device(udev, -1); +} + /** * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces * @udev: the usb_device to autosuspend @@ -1492,6 +1505,45 @@ void usb_autopm_put_interface(struct usb_interface *intf) EXPORT_SYMBOL_GPL(usb_autopm_put_interface); /** + * 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 essentially the same thing as + * usb_autopm_put_interface(): it decrements @intf's usage counter and + * queues a delayed autosuspend request if the counter is <= 0. The + * difference is that it does not acquire the device's pm_mutex; + * callers must 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 = 0; + + if (intf->condition == USB_INTERFACE_UNBOUND) { + status = -ENODEV; + } else { + udev->last_busy = jiffies; + --intf->pm_usage_cnt; + if (udev->autosuspend_disabled || udev->autosuspend_delay < 0) + status = -EPERM; + else if (intf->pm_usage_cnt <= 0 && + !timer_pending(&udev->autosuspend.timer)) { + queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, + round_jiffies_relative( + udev->autosuspend_delay)); + } + } + dev_vdbg(&intf->dev, "%s: status %d cnt %d\n", + __func__, status, intf->pm_usage_cnt); +} +EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async); + +/** * usb_autopm_get_interface - increment a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be incremented * @@ -1537,6 +1589,37 @@ int usb_autopm_get_interface(struct usb_interface *intf) 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 result is > 0. The differences + * are that it does not acquire the device's pm_mutex (callers must + * handle all synchronization issues themselves), and it does not + * autoresume the device directly (it only queues a request). After a + * successful call, the device will generally not yet be resumed. + * + * This routine can run in atomic context. + */ +int usb_autopm_get_interface_async(struct usb_interface *intf) +{ + struct usb_device *udev = interface_to_usbdev(intf); + int status = 0; + + if (intf->condition == USB_INTERFACE_UNBOUND) + status = -ENODEV; + else if (udev->autoresume_disabled) + status = -EPERM; + else if (++intf->pm_usage_cnt > 0 && udev->state == USB_STATE_SUSPENDED) + queue_work(ksuspend_usb_wq, &udev->autoresume); + dev_vdbg(&intf->dev, "%s: status %d cnt %d\n", + __func__, status, intf->pm_usage_cnt); + return status; +} +EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async); + +/** * usb_autopm_set_interface - set a USB interface's autosuspend state * @intf: the usb_interface whose state should be set * @@ -1563,6 +1646,9 @@ EXPORT_SYMBOL_GPL(usb_autopm_set_interface); void usb_autosuspend_work(struct work_struct *work) {} +void usb_autoresume_work(struct work_struct *work) +{} + #endif /* CONFIG_USB_SUSPEND */ /** |