Input: psmouse - ESD workaround fix for OLPC XO touchpad

It appears that when the XO touchpad unit resets from ESD, it sends AA
AA instead of AA 00, the psmouse-base code handles the case of AA 00 by
triggering a serio reconnect for the port, causing a full reprobe of
the device.

Testing with OFW shows that this is likely to solve the problem, so
the attached patch simply expands the existing test to also catch AA AA.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Deepak Saxena <dsaxena@laptop.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/mouse/psmouse-base.c

@@ -327,7 +327,9 @@ static irqreturn_t psmouse_interrupt(struct serio *serio,
 			goto out;
 		}
 
-		if (psmouse->packet[1] == PSMOUSE_RET_ID) {
+		if (psmouse->packet[1] == PSMOUSE_RET_ID ||
+		    (psmouse->type == PSMOUSE_HGPK &&
+		     psmouse->packet[1] == PSMOUSE_RET_BAT)) {
 			__psmouse_set_state(psmouse, PSMOUSE_IGNORE);
 			serio_reconnect(serio);
 			goto out;