79138eec1b49cbaca6a16f2bdd8579b5828aeb28 causing black screen

[Matthias Hopf]

On May 24, 09 18:17:40 +0200, Maarten Maathuis wrote:
> The problem seems fairly obvious.

Well, it wasn't to me. Actually, it still isn't.

I stumbled over this code, and asked for why this was coded this way,
without getting any answers. So I assumed that it was just a bug and
nobody cared. I remember that there are issues with gamma LUT in RandR
not being set when they ought to, which AFAIK are not fixed yet - this
looked like the culprit for this issue.

> Old style:
> Only set gamma on currently inactive (=first activation) crtcs

inactive != first activation

This assumption can have all kinds of side effects.

> New style (someone doesn't realize the situation):
> Only set gamma on currently active(=not the first activation)
> 
> So your luts are now empty and all colors become black (HW cursor is a
> world of it's own).

That would imply that somewhere(!) crtc->gamma_* is NULLed. Which I
wonder why. Also, the comment doesn't indicate what's happening here.

I will revert the commit for now, but I'm not convinced yet that this
piece of code is actually correct. But given the issues we're seeing
here, the old behavior is presumably better.

CU, and sorry for any issues caused

Matthias

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