I've just updated the post about X.Org synaptics support for the Lenovo T440, T540, X240, Helix, Yoga, X1 Carbon. For those following my blog, here is a rough diff of the updates:
- All touchpads in this series need a kernel quirk to fix the min/max ranges. It's like a happy meal toy, make sure you collect them all.
- A new kernel evdev input prop INPUT_PROP_TOPBUTTONPAD is available in 3.15. It marks the devices that require top software buttons. It will be backported to stable.
- A new option was added HasSecondarySoftButtons was added to the synaptics driver. It is automatically set if INPUT_PROP_TOPBUTTONPAD is set and if set, the driver parses the SecondarySoftButtonAreas option and honours the values in it.
- If you have the kernel min/max fixes and the new property, don't bother with DMI matching. Provide a xorg.conf.d snippet that unconditionally merges the SecondarySoftButtonAreas and rely on the driver for parsing it when appropriate