Hello

I wrote some C code to play around with the Multi-Touch (MT) protocol by reading directly from the /dev/input/event* device. I was wondering if anybody would be willing to test it on their machine. Just would like some feedback, plus there's a few things I don't quite understand.

The code is located at http://github.com/arthurchoung/linux-trackpad-demos

You'll have to build it by typing 'make'. You should end up with 3 binaries you can run (it links with -lX11 -lGL so you'll need the appropriate headers/libs)

The three binaries are (1) a square-shaped 'hockey puck' that you can move around, (2) a program that simply shows the current touches detected, and (3) a crude 'rubber band' scrolling example.

This is where it's a bit tricky, I don't entirely understand this part. On my system, I am running Slackware 14.2 on a Thinkpad X220. The device file for my trackpad is '/dev/input/event14' which also seems to be the mouse, but I'm not sure where that gets decided.

So when running the binaries, you would specify the device file as the argument. For example, './puck_demo /dev/input/event14' would be the command on my system. But it's possible that each system uses a different /dev/input/event file.

Additionally, this file needs to be readable by the user, so you would have to do a 'chmod a+r /dev/input/event14' or give the user read permissions some other way.

A few things I am interested in finding out:

(1) Does it actually work on your system?
(2) Which /dev/input/event device file worked, if any?
(3) When running 'tracking_demo', how many touches are able to be detected simultaneously? My computer only detects 2 finger touches.
(4) Any other problems you may have

Thanks