USB / PM: Allow USB devices to remain runtime-suspended when sleeping
Have dev_pm_ops.prepare return 1 for USB devices and ports so that USB
devices can remain runtime-suspended when the system goes to a sleep
state, if their wakeup state is correct and they have runtime PM enabled.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index f8bbd0b..cafc119 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -316,7 +316,13 @@
static int usb_dev_prepare(struct device *dev)
{
- return 0; /* Implement eventually? */
+ struct usb_device *udev = to_usb_device(dev);
+
+ /* Return 0 if the current wakeup setting is wrong, otherwise 1 */
+ if (udev->do_remote_wakeup != device_may_wakeup(dev))
+ return 0;
+
+ return 1;
}
static void usb_dev_complete(struct device *dev)