Hello, I will certainly have new embedded module, with an 4 wire resistive Serial touchscreen (by LG). Is a simple ps/2 or serial driver work with this type of pointing device ?
QNX doesn’t have generic driver for touchscreen (for x86)… 
There is no such thing as “generic” in the touchscreen world, mice only became generic because there was a demand for it and the early protocols, namely m$ and mousesystem, were open and free.
Here’s the list of supported touchscreen protocols, qnx.com/developers/hardware_ … chscreen=1
Try them all. If you have no luck, the next step is to get the documentation for the protocol your controller is using and adapt the example driver to suit, /usr/src/ddk-6.2.1/input/src/hardware/devi/elo/*
Look at the protocol of the touchscreen. If the protocol is one of the protocols that QNX supports, it must work in QNX.
If not, you have several options. One of those is to write the driver and the other one is to change the controller of the touchscreen. I had a touchscreen not QNX compatible but I have changed the controller card to make the touchscreen compatible (a SALT controller which is also QNX 6.2.1 compatible).
I hope it helps.