Input: zforce_ts - fix dual touch recognition

commit 6984ab1ab35f422292b7781c65284038bcc0f6a6 upstream.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/input/touchscreen/zforce_ts.c b/drivers/input/touchscreen/zforce_ts.c
index 9bbadaaf6bc3723f044a9c44e8619773d242ec8f..7b3845aa5983ad57892a0022990f3353bcca82b6 100644 (file)
--- a/drivers/input/touchscreen/zforce_ts.c
+++ b/drivers/input/touchscreen/zforce_ts.c
@@ -370,8 +370,8 @@ 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],