ep121

xinput

Returns

⎡ Virtual core pointer                        id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                    id=4    [slave  pointer  (2)]
⎜   ↳ Logitech USB-PS/2 Optical Mouse               id=12   [slave  pointer  (2)]
⎜   ↳ Wacom ISDv4 90 Pen stylus                     id=13   [slave  pointer  (2)]
⎜   ↳ eGalax_eMPIA Technology Inc. PCAP MultiTouch Controller       id=14   [slave  pointer  (2)]
⎜   ↳ Wacom ISDv4 90 Pen eraser                     id=17   [slave  pointer  (2)]
⎜   ↳ Microsoft Bluetooth Mobile Keyboard 6000      id=11   [slave  pointer  (2)]
⎣ Virtual core keyboard                       id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard                     id=5    [slave  keyboard (3)]
    ↳ Power Button                                    id=6    [slave  keyboard (3)]
    ↳ Video Bus                                       id=7    [slave  keyboard (3)]
    ↳ Power Button                                    id=8    [slave  keyboard (3)]
    ↳ Sleep Button                                    id=9    [slave  keyboard (3)]
    ↳ USB 2.0 Camera                                  id=10   [slave  keyboard (3)]
    ↳ Eee PC WMI hotkeys                              id=15   [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard                    id=16   [slave  keyboard (3)]

so, the touchscreen has id 14

xinput disable 14

Create the file /etc/udev/rules.d/99-local.rules and add inside

SUBSYSTEMS=="usb", ATTRS{idVendor}=="0eef", ATTRS{idProduct}=="a001", RUN="/bin/rm /dev/input/event%n"

Reboot

Source : http://forums.gentoo.org/viewtopic-t-898760-start-0.html