Backlight off after suspend-to-disk on Powerbook
Submitted by Jonathan Kleinehellefort
Assigned to Nouveau Project
Description
After waking up from the hibernate (software suspend), the LCD backlight turns off. The machine wakes up correctly otherwise, you can even see the contents of the screen if you look very carefully.
The backlight does turn off correctly with DPMS, probably due to the fix in bug #29685.
I examined the contents of the registers mentioned in the above report using radeontool. Before hibernate I get:
0x0060081c 0x86066055
0x000010f0 0x83e60535
And after hibernate:
0x0060081c 0x86066055
0x000010f0 0x80007fff
Restoring 0x10f0 to the previous value turns the backlight back on.
The machine is a PowerBook6,2 12", with an
nVidia Corporation NV34M [GeForce FX Go5200] [10de:0329] (rev a1).
It is running Debian xserver-xorg-video-nouveau 1:0.0.16+git20100825+390f1c86-1 and vanilla Linux 2.6.36.
I'm going to file another bug for the backlight control, which also does not work, but works fine with nv.