forums.ps2dev.org

download from http://ps2dev.org/kb.x?T=1136
here's half the readme:

What is it
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A touchscreen driver which can be used instead of ps2mouse.irx.

What does it do
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Interprets touch input from a Lilliput 7" touchscreen. You should
be able to use it with any application that loads ps2mouse.irx.
This device appears to the PS2 as a single button mouse.

Here is a link to a description*:
http://www.mp3car.com/store/product_inf ... ucts_id=33

* I am in no way affiliated nor did I buy my screen from mp3car.com

Installation
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Rename touchscreen.irx to ps2mouse.irx and use with your playstation2
that has a touchscreen.

Load the driver with something like this:
SifLoadModule("host:ps2mouse.irx", 0, 0);

Requirements
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usbd.irx - I use an official Sony release. Let me know if the
ps2sdk release works for you.

This is quite cool stuff actually :) gives me another reason to get one of those lilliputs.