In order to generate proper key events by overlay buttons and adjust the touch events to a clipped surface, this series offers a documented, device-tree-based solution by means of helper functions. An implementation for a specific touchscreen driver is also included.
I believe there's at least some x86 tablets that have such a layout, so maybe ACPI bindings would also make sense? Or can this be supported by your DT-based solution?
I'm not sure if it would really be needed for existing devices, though. It's possible they were all handled by touchscreen controller firmware so far.
Hans, do you remember if we've encountered any Silead or Goodix devices where the soft button overlay didn't work due to missing firmware support?
