My laptop (an HP) has a built-in gizmo which acts like a scroll wheel, only
it's not a wheel; it's a rocker switch.  Thus, it's really much more like
two additional mouse buttons than it is like a scroll wheel.

The pmsi driver, with DEBUG defined, says:
pmsiprobe: intellimode -> 6
which is an error indicating that an attempt to set "intellimode" failed.

On the other hand, the regular pms driver only seems to see the two "regular"
buttons.

So... should I be treating this as a bug in the pmsi driver (not probing
device correctly) or in pms (not finding all the buttons)?

-s