usbtouchscreen

http://bboytaiwan.blogspot.com/2009/06/multi-point-touch-panel-driver.html

usbtouch_irq ->
usbtouch_process_pkt ->
read_data ->
input_report_key(BTN_TOUCH) -> input_event(EV_KEY)
input_report_abs(ABS_X, ABS_Y) -> input_event(EV_ABS)