W701 backlight controls do not work after suspend

[xiphmont]

Breaking this into a new thread to make it more visible to Lenovo and prospective W-series buyers.

It turns out the "backlight controls don't work after suspend" problem the W510 folks are complaining about hits the W701 too. In both Linux and Windows, the backlight brightness controls don't work at all anymore after suspend or hibernate. it is 100% reliable. Only a reboot brings it back. Other than that, suspend and hibernate work fine.

It seems the W510 users have been complaining about this since day 1 and Lenovo has not yet acknowledged the problem. We need to make sure they understand this is a real issue.