Input: zforce_ts - fix dual touch recognition

[ Upstream commit 6984ab1ab35f422292b7781c65284038bcc0f6a6 ]

A wrong decoding of the touch coordinate message causes a wrong touch
ID. Touch ID for dual touch must be 0 or 1.

According to the actual Neonode nine byte touch coordinate coding,
the state is transported in the lower nibble and the touch ID in
the higher nibble of payload byte five.

Signed-off-by: Knut Wohlrab <Knut.Wohlrab@de.bosch.com>
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/drivers/input/touchscreen/zforce_ts.c b/drivers/input/touchscreen/zforce_ts.c
index 19880c7385e35ab0c93d4d5746e081ca84b9b108..d618f67a9f48cba708e46df628e83f014e15c658 100644 (file)
--- a/drivers/input/touchscreen/zforce_ts.c
+++ b/drivers/input/touchscreen/zforce_ts.c
@@ -359,8 +359,8 @@ static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
                        point.coord_x = point.coord_y = 0;
                }
 
-               point.state = payload[9 * i + 5] & 0x03;
-               point.id = (payload[9 * i + 5] & 0xfc) >> 2;
+               point.state = payload[9 * i + 5] & 0x0f;
+               point.id = (payload[9 * i + 5] & 0xf0) >> 4;
 
                /* determine touch major, minor and orientation */
                point.area_major = max(payload[9 * i + 6],