Comment 9 for bug 939868

Hello

I have the same problem on Sony VPCCB4C5E

I have created a patch with an udev rule and a specific keymap for my model

I will submit this after reading /usr/share/doc/udev/README.keymap.txt.gz

You may try:
$ sudo /lib/udev/keymap input/eventX 0x05 f21

This should work for fn+f1 -> touchpad toggle

To weird things:
* "$ sudo keymap -i" writes scancodes + 7. So you have to subtract 7 to get the usable scan code:
    fn+f1: 0x0c -> 0x05
* KEY_TOUCHPAD_TOGGLE does nothing, you have to use KEY_F21 instead (hence "f21")