https://bugs.freedesktop.org/show_bug.cgi?id=29026
--- Comment #10 from Daniel direx@betriebsdirektor.de 2010-10-12 15:45:01 PDT --- (In reply to comment #9)
If s/r used to work, when did it last work, and can you bisect what commit broke it?
Sorry for the late reply. I cannot find the commit which broke it, however this is still an issue.
I figured out that using xrandr after resuming fixes the garbled screen (setting a different resolution and restoring the original one afterwards).