backlight doesn't turn on when resuming from suspend

[Daren]

Binary package hint: pm-utils

Hi guys,
My Dell Inspiron 8500 doesn't resume properly when suspending. The keyboard responds, and it looks as though everything system-wise is intact, except the backlight doesn't turn on.

The only way to get the backlight on again is to do a reboot.

Backlight control works fine when the screensaver/power management triggers it to turn off/on again, but resuming has never worked.

This laptop used to have an NVidia card (which has since stopped working altogether), and I'm pretty sure that resuming worked OK on the old video card. It now has an ATI Radeon card.

I have tried setting radeon.modeset=0 and/or modeset=0 on boot options but that locks the machine after a few minutes (as reported here https://bugs.launchpad.net/ubuntu/+source/linux/+bug/574848).

Also tried pm-suspend with various options, as well as playing with the quirkdb file, all to no avail.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: pm-utils 1.3.0-1ubuntu2 [modified: usr/lib/pm-utils/video-quirks/20-video-quirk-pm-dell.quirkdb]
ProcVersionSignature: Ubuntu 2.6.32-22.33-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-22-generic i686
Architecture: i386
Date: Sat May 29 19:07:40 2010
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
PackageArchitecture: all
ProcEnviron:
 LANG=en_AU.utf8
 SHELL=/bin/bash
SourcePackage: pm-utils

[Randy West (randywest55)]

This bug affects me as well as noted in Bug #574848. Whereas the 10.5 ATI drivers seem to fix the problem for many, my older Radeon Mobility 7500 on a Dell Inspiron 5100 is unsupported by the update and hence remains unfixed.

[Paul Harper (pharper26855)]

On my old Dell C610 with ATI Mobility M6 LY has the same problem.

[Dan Becker (beckerz)]

My averetec 2110(msi motherboard) with ATI Mobility x200 has the same problem. ATI should support their old chips.

[Dimitris Menemenlis (dmenemenlis)]

Same problem with Dell Inspiron 8600
ATI Mobility Radeon 9600 M10
Ubuntu 10.04
Kernel 2.6.32-35-generic

Any resolution to this issue?

[Serge Hallyn (serge-hallyn)]

Please reply if this is still an issue on a supported release.