I found the problem on Debian Wheezy/Sid with both Linux 2.6.38 and 2.6.39.
udev won’t modprobe any module for the touchpad. To fix it:
echo psmouse > /etc/modules modprobe psmouse
Unfortunnatly the touchpad will be detected as a PS/2 Mouse not as an ALPS Touchpad. Xorg won’t find any rules from
/usr/share/X11/xorg.conf.d to associate drivers to devices. To help it just create a file in /etc/X11/xorg.conf.d
with the following content:
Section "InputClass" Identifier "Touchpad Emulation" MatchDevicePath "/dev/input/event1" Driver "evdev" Option "GrabDevice" "true" EndSection
This solution is less thant satisfactory because XInput will see the touchpad as a mouse, which will prevent to do any sensible configuration.
I suspect this is related to this bug: https://bugzilla.kernel.org/show_bug.cgi?id=14660.