So after much searching, I can confirm that the Sony Sixaxis keypad layout does work, and it is configurable.
No, I did not found yet the kernel module or kernel adaptation that was responsible for this.
What I do know is that since Android 4.0 there is partial support for Sixaxis and Xbox 360 keypads. I’m trying to enable the PS3 keypad ass well
If you have this in /system/usr/keylayout/ the Sixaxis works over usb.
Do NOT mess with the generic.kl or qwerty.kl or other kcm files.