Bug#523589: xserver-xorg-video-radeon: dualhead broke with upgrade

[Alex Deucher]

On 4/15/09, di dit <didit21 at gmail.com> wrote:
> 2009/4/14 Alex Deucher <alexdeucher at gmail.com>:
>
> > Both heads are probably using the same crtc, but xrandr isn't smart
>  > enough to assign a different one.  You can see what crtc is in use by
>  > running xrandr --verbose.  You can assign a different crtc to the
>  > other head like so:
>  > xrandr --output DVI-1 --crtc 1 --mode 1280x1024 --left-of DVI-0
>
>
>
> Thanks for the suggestion. Unfortunately, it doesn't solve my problem.
>  Here are the results of some tests obtained using the following
>  minimal xorg.conf file:
>  Section "Screen"
>         Identifier      "screen"
>         SubSection "Display"
>                 Depth           24
>                 Virtual 2600 1024
>         EndSubSection
>  EndSection
>
>  The output of xrandr --verbose at each step is given in the attached file.
>
>  1/ startx (window manager e16) results in monitors in clone mode as expected.
>  DVI-0 and DVI-1 do indeed use the same crtc (0).
>
>  2/ xrandr --output DVI-0 --crtc 0 --mode 1280x1024
>  nothing happens (as expected)
>
>  3/ xrandr --output DVI-1 --crtc 1 --mode 1280x1024
>  The monitor connected to DVI-0 enter power save mode.
>
>  4/ xrandr --output DVI-0 --off
>  nothing happens except that the following command wouldn't change
>  anything without it.
>
>  5/ xrandr --output DVI-0 --crtc 0 --mode 1280x1024
>  DVI-0 monitor goes on, DVI-1 monitor goes into power save mode
>
>  Another "funny" issue is that after running startx and without
>  "playing" with xrandr, if I switch off the
>  monitor connected to DVI-1 then the mouse pointer doesn't move on the
>  other monitor. This problem
>  doesn't exist when the monitor connected to DVI-1 is on and the other one off.
>
>

Sounds like:
https://bugs.freedesktop.org/show_bug.cgi?id=21199

Does:
xset dpms force off
followed by moving the mouse cause both screens to come on?

Alex