Problems with ati driver on Tibook

[Alex Deucher]

On Tue, Dec 22, 2009 at 6:58 PM, John R. Dunning <jrd at jrd.org> wrote:
>    From: "John R. Dunning" <jrd at jrd.org>
>    Date: Tue, 22 Dec 2009 06:54:32 -0500
>
>        From: "John R. Dunning" <jrd at jrd.org>
>        Date: Mon, 21 Dec 2009 11:36:52 -0500
>
>            From: Alex Deucher <alexdeucher at gmail.com>
>            Date: Mon, 21 Dec 2009 11:26:21 -0500
>
>
>            I think this patch should fix it.
>
>        Thanks v.much!  I'll try it tonight.
>
>    Yup, that did the trick.  Thanks so much!
>
> Hmmm.  Maybe I spoke too soon.  A lot of stuff works, but when it
> decides to blank the screen after being idle for a while, it falls
> back into the wierd mode where it looks like the backlight is screwed
> up.  Ie, the same thing it did at startx time, before I applied your
> patch.  Hitting a key or something causes it to immediately pop back
> out and look normal again.
>
> Could it be that there are multiple paths through the driver, and
> there's another place that needs that treatment?  Any more info I
> could provide which would help diagnose?

Screen blanking turns off the crtcs and outputs and isn't directly
related to mode timing which was what the previous issue was.  Macs
tend to have the backlight wired up strangely which is probably the
case for you.  In some systems it's wired up to an external controller
or the levels are reversed.

Alex