HID: sony: Drop invalid Sixaxis input reports

When connected via Bluetooth the sixaxis periodically sends reports with an ID
of 1, the second byte 0xff and the rest zeroed.  These reports are not related
to the controller state and must be dropped to avoid generating false input
events.

Link: http://www.spinics.net/lists/linux-bluetooth/msg63028.html
Signed-off-by: Frank Praznik <frank.praznik@oh.rr.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

drivers/hid/hid-sony.c

@@ -1277,6 +1277,17 @@ static int sony_raw_event(struct hid_device *hdev, struct hid_report *report,
 	 * has to be BYTE_SWAPPED before passing up to joystick interface
 	 */
 	if ((sc->quirks & SIXAXIS_CONTROLLER) && rd[0] == 0x01 && size == 49) {
+		/*
+		 * When connected via Bluetooth the Sixaxis occasionally sends
+		 * a report with the second byte 0xff and the rest zeroed.
+		 *
+		 * This report does not reflect the actual state of the
+		 * controller must be ignored to avoid generating false input
+		 * events.
+		 */
+		if (rd[1] == 0xff)
+			return -EINVAL;
+
 		swap(rd[41], rd[42]);
 		swap(rd[43], rd[44]);
 		swap(rd[45], rd[46]);