xHCI: set USB2 hardware LPM

If the device pass the USB2 software LPM and the host supports hardware
LPM, enable hardware LPM for the device to let the host decide when to
put the link into lower power state.

If hardware LPM is enabled for a port and driver wants to put it into
suspend, it must first disable hardware LPM, resume the port into U0,
and then suspend the port.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 0097136..a4cd6c5 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -343,6 +343,7 @@
 		 * address is set
 		 */
 	int	(*update_device)(struct usb_hcd *, struct usb_device *);
+	int	(*set_usb2_hw_lpm)(struct usb_hcd *, struct usb_device *, int);
 };
 
 extern int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb);