xrandr doesn't unclone CRTCs...

[Alex Deucher]

On Nov 8, 2007 3:52 PM, Matthias Hopf <mhopf at suse.de> wrote:
> It seems that my first patch doesn't address all issues. Find another
> patch attached that improves things even more.
>
> Apparently pick_crtcs_score() didn't set up crtcs references correctly
> if anything but the last output resulted in the best score.
>
> I'm pretty sure that there is another bug lurking around that will make
> reuse of crtcs difficult, but it will only show up on configurations
> with more than 2 outputs active at the same time. Maybe even only on
> configurations with more than 2 crtcs, and I don't think we have such
> beasts with RandR support available yet.

FWIW, I ran into similar issues when I was writing clone support for
radeon.  On many laptops you have 4 outputs (LVDS, DVI, VGA, tv-out)
that can be cloned in various configurations.  Cloning worked when the
xserver came up or if you hard-coded the crtc mappings, but xrandr
--auto failed.  I had suspected xrandr at the time as well, but never
got the chance to debug it.  I'll hopefully be able to give your patch
a try later this week.

Alex