https://bugzilla.kernel.org/show_bug.cgi?id=42112
mrsteven@gmx.de changed:
What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED Resolution| |INVALID
--- Comment #4 from mrsteven@gmx.de 2011-08-30 20:29:42 --- Oh, it seems I have to apologize for my noise, because the problem was the monitor itself: It somehow got confused and "forgot" its EDID data. The problem was fixed by pulling its power line and then plugging it in again, i.e. doing a hard reset of the monitor.
And yes, this makes perfect sense, because I see no commit relating to EDID reading, parsing, or the handling of the data in the radeon driver. The only one I see is a change for some HDMI connectors, which doesn't affect me.
Sorry for any inconvenience.