In XFree 3.x, additional pointing devices, like mice or tablets, are defined
through the use of an Xinput section. The primary mouse is
defined as usual:
My mouse is a wheel mouse, thus the protocol is IMPS/2. ZAxisMapping line is also needed for the wheel to work.
I also want the mouse to always work alongside the other one, and this is achieved
through the AlwaysCore option. If. for example, this was
a serial mouse, the Port would read
"/dev/ttyS0" for COM1.