Input: elantech - relax signature checks

Apparently there are Elantech touchpads that report non-zero in the 2nd byte
of their signature. Adjust the detection routine so that if 2nd byte is
zero and 3rd byte contains value that is not a valid report rate, we still
assume that signature is valid.

Tested-by: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Dmitry Torokhov 2010-05-19 10:11:13 -07:00
parent d4ae84a84b
commit a083632eaf

View file

@ -575,6 +575,24 @@ static struct attribute_group elantech_attr_group = {
.attrs = elantech_attrs,
};
static bool elantech_is_signature_valid(const unsigned char *param)
{
static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
int i;
if (param[0] == 0)
return false;
if (param[1] == 0)
return true;
for (i = 0; i < ARRAY_SIZE(rates); i++)
if (param[2] == rates[i])
return false;
return true;
}
/*
* Use magic knock to detect Elantech touchpad
*/
@ -617,7 +635,7 @@ int elantech_detect(struct psmouse *psmouse, bool set_properties)
pr_debug("Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
param[0], param[1], param[2]);
if (param[0] == 0 || param[1] != 0) {
if (!elantech_is_signature_valid(param)) {
if (!force_elantech) {
pr_debug("Probably not a real Elantech touchpad. Aborting.\n");
return -1;