> We conclude that there is no AUX port.
> No PS/2 mouse that can be used.

Does it mean that the hardware is somehow lying or is the check too
strong ?

> You can to put #if 0 ... #endif around the four
> if statements following the comment
> 
> /*
>  * Bit assignment test - filters out PS/2 i8042's in AT mode
>  */
> 
> in i8042.c (since also your mouse was filtered away).

I've done that. Enclosed are some logs from my tests. In short:

     - with no psmouse_noext option, the synaptics touchpad is
       detected, but there a lots of synchro lost error messages.

     - with psmouse_noext set, the mouse is erratic when using XFree
       (not with the synaptics specific driver)

Frédéric