Comment # 2 on bug 1079862 from Peter S�tterlin

No, as I wrote, in 4.14.15, rmi is not used at all (for whatever reason).  The
touchpad is used via the psmouse driver, and that works.

Maybe some default priority has changed and now rmi is enforced?

I'll see if I can use psmouse.synaptics_intertouch to force usage of rmi in
4.14.15 (or usage of psmouse in 4.15?)

Comment # 1 on bug 1079862 from Jiri Slaby

The only commit between 4.14 and 4.15 for rmi is this:
commit ef14a4bf0910d06c7e202552914028d4956809cb
Author: Andrew Duggan <aduggan@synaptics.com>
Date:   Tue Oct 17 18:37:36 2017 -0700

    HID: rmi: Check that a device is a RMI device before calling RMI functions

And it doesn't look related. Currently, I don't see a way how this could not be
handled in 4.14 by rmi and in 4.15 it is.