Re: Problem with latest PowerBook alu post Feb 2005 and wakeup.
On Sat, 2005-05-14 at 22:59 +0200, Jesus Climent wrote:
> I got a new PowerBook at work, and after upgrading to 2.6.12-rc4 I am
> experiencing some regression problems (I was using 2.6.12-rc3 + sleep patches).
> The system goes to sleep fine, and usually recovers from the hibernation state
> fine, but sometimes I get corruption problems: the screen is mangled in a way
> that looks like there are some sync problems with the screen. I can read most
> of the characters, but they look like interlaced.
This is a known issue. Another workaround is to bring backlight all the
way down to 0 and back up a few times until the screen "catches up". The
problem has something to do with the LCD panel powerup sequence.
Unfortunately, I don't have any real informations about what should be
done in that area, and every time I tweak that code to fix some
machines, I break others. Apparently all panel types need a different
seuqnce for beeing properly powered up but I don't have those
If you want to play around, maybe tweak with the code in
radeonfb_unblank that deals with LVDS_GEN_CNTL bits and see if you can
get it to work more reliably by adding delays here or there...