Set Option "HasSecondarySoftButtons" "on" in 50-synaptics.conf for devices
    
      with the touchpad_softbutton_top udev quirk, to keep topbuttons working on
      kernels which don't set INPUT_PROP_TOPBUTTONPAD
    - Add W540 to 70-touchpad-quirks.rules as touchpad_softbutton_top (#1096436)