USB: revert "don't use reset-resume if drivers don't support it"

This reverts Linus's previous patch that is in mainline to make it
easier for the USB hub.c patches that follow this to apply cleanly.  The
functionality will be added back in a followon patch in this series.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/hub.c

@@ -644,48 +644,6 @@ static void hub_stop(struct usb_hub *hub)
 
 #ifdef CONFIG_PM
 
-/* Try to identify which devices need USB-PERSIST handling */
-static int persistent_device(struct usb_device *udev)
-{
-	int i;
-	int retval;
-	struct usb_host_config *actconfig;
-
-	/* Explicitly not marked persistent? */
-	if (!udev->persist_enabled)
-		return 0;
-
-	/* No active config? */
-	actconfig = udev->actconfig;
-	if (!actconfig)
-		return 0;
-
-	/* FIXME! We should check whether it's open here or not! */
-
-	/*
-	 * Check that all the interface drivers have a
-	 * 'reset_resume' entrypoint
-	 */
-	retval = 0;
-	for (i = 0; i < actconfig->desc.bNumInterfaces; i++) {
-		struct usb_interface *intf;
-		struct usb_driver *driver;
-
-		intf = actconfig->interface[i];
-		if (!intf->dev.driver)
-			continue;
-		driver = to_usb_driver(intf->dev.driver);
-		if (!driver->reset_resume)
-			return 0;
-		/*
-		 * We have at least one driver, and that one
-		 * has a reset_resume method.
-		 */
-		retval = 1;
-	}
-	return retval;
-}
-
 static void hub_restart(struct usb_hub *hub, int type)
 {
 	struct usb_device *hdev = hub->hdev;
@@ -731,8 +689,8 @@ static void hub_restart(struct usb_hub *hub, int type)
 		 * turn off the various status changes to prevent
 		 * khubd from disconnecting it later.
 		 */
-		if (status == 0 && !(portstatus & USB_PORT_STAT_ENABLE) &&
-				persistent_device(udev)) {
+		if (udev->persist_enabled && status == 0 &&
+				!(portstatus & USB_PORT_STAT_ENABLE)) {
 			if (portchange & USB_PORT_STAT_C_ENABLE)
 				clear_port_feature(hub->hdev, port1,
 						USB_PORT_FEAT_C_ENABLE);