From a083632eaf6231162b33e40561cfec6a9c156945 Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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 <eric.piel@tremplin-utc.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
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 232556a89c4a7..b18862b2a70e1 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;
--
GitLab