From: Caleb Connolly caleb@connolly.tech
commit 30b3f68715595dee7fe4d9bd91a2252c3becdf0a upstream.
The touch coordinate register contains the following:
byte 3 byte 2 byte 1 +--------+--------+ +-----------------+ +-----------------+ | | | | | | | | X[3:0] | Y[3:0] | | Y[11:4] | | X[11:4] | | | | | | | | +--------+--------+ +-----------------+ +-----------------+
Bytes 2 and 1 need to be shifted left by 4 bits, the least significant nibble of each is stored in byte 3. Currently they are only being shifted by 3 causing the reported coordinates to be incorrect.
This matches downstream examples, and has been confirmed on my device (OnePlus 7 Pro).
Fixes: 0145a7141e59 ("Input: add support for the Samsung S6SY761 touchscreen") Signed-off-by: Caleb Connolly caleb@connolly.tech Reviewed-by: Andi Shyti andi@etezian.org Link: https://lore.kernel.org/r/20210305185710.225168-1-caleb@connolly.tech Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/input/touchscreen/s6sy761.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/input/touchscreen/s6sy761.c +++ b/drivers/input/touchscreen/s6sy761.c @@ -145,8 +145,8 @@ static void s6sy761_report_coordinates(s u8 major = event[4]; u8 minor = event[5]; u8 z = event[6] & S6SY761_MASK_Z; - u16 x = (event[1] << 3) | ((event[3] & S6SY761_MASK_X) >> 4); - u16 y = (event[2] << 3) | (event[3] & S6SY761_MASK_Y); + u16 x = (event[1] << 4) | ((event[3] & S6SY761_MASK_X) >> 4); + u16 y = (event[2] << 4) | (event[3] & S6SY761_MASK_Y);
input_mt_slot(sdata->input, tid);