From: KT Liao <kt.l...@emc.com.tw> [ Upstream commit d899520b0431e70279bfb5066ecb6dc91d0b7072 ]
One of Elan modules with sample version is 0x74 and hw_version is 0x03 has a bug in absolute mode implementation, so let it run in default PS/2 relative mode. Signed-off-by: KT Liao <kt.l...@emc.com.tw> Signed-off-by: Dmitry Torokhov <dmitry.torok...@gmail.com> Signed-off-by: Sasha Levin <alexander.le...@microsoft.com> --- drivers/input/mouse/elantech.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index 59603a5728f7..c519c0b09568 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -1711,6 +1711,17 @@ int elantech_init(struct psmouse *psmouse) etd->samples[0], etd->samples[1], etd->samples[2]); } + if (etd->samples[1] == 0x74 && etd->hw_version == 0x03) { + /* + * This module has a bug which makes absolute mode + * unusable, so let's abort so we'll be using standard + * PS/2 protocol. + */ + psmouse_info(psmouse, + "absolute mode broken, forcing standard PS/2 protocol\n"); + goto init_fail; + } + if (elantech_set_absolute_mode(psmouse)) { psmouse_err(psmouse, "failed to put touchpad into absolute mode.\n"); -- 2.14.1