From a083632eaf6231162b33e40561cfec6a9c156945 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Wed, 19 May 2010 10:11:13 -0700 Subject: [PATCH] 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 Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/elantech.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index 232556a89c4a..b18862b2a70e 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -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; -- 2.39.5