[PATCH 4.5 73/88] Revert "USB / PM: Allow USB devices to remain runtime-suspended when sleeping"

[Greg Kroah-Hartman]

4.5-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@xxxxxxxxxx>

commit 9be427efc764464fbcbc1ca3f0d34f575cb0f037 upstream.

This reverts commit e3345db85068ddb937fc0ba40dfc39c293dad977, which
broke system resume for a large class of devices.

Devices that after having been reset during resume need to be rebound
due to a missing reset_resume callback, are now left in a suspended
state. This specifically broke resume of common USB-serial devices,
which are now unusable after system suspend (until disconnected and
reconnected) when USB persist is enabled.

During resume, usb_resume_interface will set the needs_binding flag for
such interfaces, but unlike system resume, run-time resume does not
honour it.

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/core/port.c |    6 ------
 drivers/usb/core/usb.c  |    8 +-------
 2 files changed, 1 insertion(+), 13 deletions(-)

--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -249,18 +249,12 @@ static int usb_port_runtime_suspend(stru
 
 	return retval;
 }
-
-static int usb_port_prepare(struct device *dev)
-{
-	return 1;
-}
 #endif
 
 static const struct dev_pm_ops usb_port_pm_ops = {
 #ifdef CONFIG_PM
 	.runtime_suspend =	usb_port_runtime_suspend,
 	.runtime_resume =	usb_port_runtime_resume,
-	.prepare =		usb_port_prepare,
 #endif
 };
 
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -311,13 +311,7 @@ static int usb_dev_uevent(struct device
 
 static int usb_dev_prepare(struct device *dev)
 {
-	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;
+	return 0;		/* Implement eventually? */
 }
 
 static void usb_dev_complete(struct device *dev)