Input: ALPS - fix touchpad detection when buttons are pressed

commit 99c90ab31fad855b9da9dee3a5aa6c27f263e9d6 upstream.

ALPS touchpad detection fails if some buttons of ALPS are pressed.
The reason is that the "E6" query response byte is different from
what is expected.

This was tested on a Toshiba Portege R500.

Signed-off-by: Akio Idehara <zbe64533@gmail.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
index 003587c71f43edd8d6ad315d5ffaf514ad3705d7..9c40c1129a0f94f59b1f581c955946b5b9d684c4 100644 (file)
--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -421,7 +421,9 @@ static const struct alps_model_info *alps_get_model(struct psmouse *psmouse, int
 
        /*
         * First try "E6 report".
-        * ALPS should return 0,0,10 or 0,0,100
+        * ALPS should return 0,0,10 or 0,0,100 if no buttons are pressed.
+        * The bits 0-2 of the first byte will be 1s if some buttons are
+        * pressed.
         */
        param[0] = 0;
        if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES) ||
@@ -437,7 +439,8 @@ static const struct alps_model_info *alps_get_model(struct psmouse *psmouse, int
        psmouse_dbg(psmouse, "E6 report: %2.2x %2.2x %2.2x",
                    param[0], param[1], param[2]);
 
-       if (param[0] != 0 || param[1] != 0 || (param[2] != 10 && param[2] != 100))
+       if ((param[0] & 0xf8) != 0 || param[1] != 0 ||
+           (param[2] != 10 && param[2] != 100))
                return NULL;
 
        /*