Input: elantech - fix detection of touchpad on ASUS s301l

commit 271329b3c798b2102120f5df829071c211ef00ed upstream.

Adjust Elantech signature validation to account fo rnewer models of
touchpads.

Reported-and-tested-by: Màrius Monton <marius.monton@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 1913301..85e7523 100644 (file)
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -1223,6 +1223,13 @@ static bool elantech_is_signature_valid(const unsigned char *param)
        if (param[1] == 0)
                return true;
 
+       /*
+        * Some models have a revision higher then 20. Meaning param[2] may
+        * be 10 or 20, skip the rates check for these.
+        */
+       if (param[0] == 0x46 && (param[1] & 0xef) == 0x0f && param[2] < 40)
+               return true;
+
        for (i = 0; i < ARRAY_SIZE(rates); i++)
                if (param[2] == rates[i])
                        return false;