Bug#565344: [xserver-xorg-video-radeon] Black screen after resume from suspend to disk/RAM

[Michel Dänzer]

On Tue, 2010-01-26 at 13:41 +0100, Bruno Kleinert wrote: 
> Am Dienstag, den 19.01.2010, 13:46 +0100 schrieb Michel Dänzer:
> > On Tue, 2010-01-19 at 13:23 +0100, Bruno Kleinert wrote: 
> > > Maybe it's some crazy bullshit, but I have a guess where this could come
> > > from: ;) gnome-screensaver fades the display to black when it gets
> > > active, maybe this is done by manipulating color/contrast/whatever
> > > settings (?). I guess so, because the text "snapshotting the system" at
> > > the text console is often very dark and sometimes invisiable after
> > > gnome-screensaver got active to lock the screen before the machine
> > > starts the suspend procedure.
> > > Now, if the machine gets resumed, maybe these color/contrast/whatever
> > > settings don't get successfully restored or restored at all.
> > 
> > If that is the case, running something like
> > 
> > DISPLAY=:0 xgamma -gamma 1.0
> > 
> > from an ssh login might restore the display.
> Great, that helps! After calling this command also the text console
> becomes visible again, when I switch to a text VT.
> 
> Before I executed xgamma -gamma 1.0 I queried the X server by calling
> xgamma about the current settings and the output of xgamma was, that the
> values for RGB were already all set to 1.0! So it looks as if the state
> of the X server and the graphics hardware aren't the same after
> resuming.

Maybe the X server or driver doesn't (properly) restore the hardware
CLUT on resume.

Does this workaround also help on the other machine with an Intel GPU?

> Is there a possibility to query the graphics hardware about gamma
> settings directly?

Not sure there's anything better than looking at the monitor. :)


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer