Not all touchpad kernel drivers supply the x/y resolution. Let the udev hwdb
fix this up where possible and read the value from it.
This is intentionally only used on touchpads, touchscreen devices without
resolution should be considered buggy and fixed in the kernel.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Store it as identifier in the device group, any two devices that have a
the same non-NULL identifier share the group.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>