Touchscreen drivers are pretty much a commodity now. You see a lot of the same manufacturers over and over (Atmel, eGalax/EETI, FocalTouch, TI, etc). The prob

Touchscreen drivers are pretty much a commodity now. You see a lot of the same manufacturers over and over (Atmel, eGalax/EETI, FocalTouch, TI, etc). The problem is that every hardware designer hooks up a different GPIO line for the touch interrupt signal and so you're deep into the kernel to hook that all up. Devicetree has made this lot easier now, though. Then you have smaller issues like setting up calibration and TSLIB/filtering files, but that's a lot easier than it was five years ago. Multitouch can still be hairy depending on the target O/S.