Touchscreen Driver TMG120

Touch Screen Dash

We acquired a shiny Avnet Display Kit for use with our Microzed board.  Our first project on this kit was a basic dash display demo, which ran Xilinx Linux on a Zynq 7Z010 SoC with the aid of some Xylon graphics IP.  However we hit a speed bump in our progress.  Our touchscreen wouldn’t work under Linux!

Problems with the touchscreen driver TMG210

After a few days of discussions with various forums and our local Xilinx FAE we found the problem.  The touchscreen chipset was the same but as the chipset (the TMG120 from Cypress) is basically a touch screen microcontroller – it can come with various firmware.  It turns out Avnet had changed the firmware supplier with a new version of the kit.   Not worrying about this we looked into the Linux driver for the old firmware.  We identified the key code and with the aid of some standalone code drivers which worked, changed a couple of lines and it worked.  It still needs some work but it was good enough for our demo!

If you are having driver issues with your kit, feel free to download the changed C file Touchscreen Driver TMG120 below and enjoy:

Driver File C Code

Let us know how it goes.