[PATCH 4.9 096/101] Input: elantech - fix V4 report decoding for module with middle key

[Greg Kroah-Hartman]

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

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

From: ??? <kt.liao@xxxxxxxxxx>

commit e0ae2519ca004a628fa55aeef969c37edce522d3 upstream.

Some touchpad has middle key and it will be indicated in bit 2 of packet[0].
We need to fix V4 formation's byte mask to prevent error decoding.

Signed-off-by: KT Liao <kt.liao@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/input/mouse/elantech.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -800,7 +800,7 @@ static int elantech_packet_check_v4(stru
 	else if (ic_version == 7 && etd->samples[1] == 0x2A)
 		sanity_check = ((packet[3] & 0x1c) == 0x10);
 	else
-		sanity_check = ((packet[0] & 0x0c) == 0x04 &&
+		sanity_check = ((packet[0] & 0x08) == 0x00 &&
 				(packet[3] & 0x1c) == 0x10);
 
 	if (!sanity_check)