We are trying to modernize an older Linux build from another company and make it work in newer hardware. These are miniature pc running in a industrial environment also known as controllers. The front panel is basically a touch screen and below it are some buttons and a big knob next to the screen. No keyboard. The buttons are mapped to F1-F9 function keys and the knob is mapped to key_left and key_right. At the time they modified a file called pc_keyb.c to add more functionality to the knob like if you turn it quickly it will send page_up and page_down. I have this source but this does not seem to exists any more. It appears to be around in the late 90's. It has not been modified much and I think I can put there code somewhere else but where? Can anyone point me to wich file(s) or folder I start looking at. I know this is not much info!