Red Hat Bugzilla – Bug 550895
Cannot adjust backlight brightness on Sony Vaio FW290
Last modified: 2010-03-08 02:46:35 EST
Description of problem:
It is impossible to dim backlight UNLESS a patched DSDT is loaded at boot time. Then all is well.
The full details, including work-around, were documented by an Ubuntu user here
For Fedora, I use the tuxonice kernel to load the patched DSDT.
Version-Release number of selected component (if applicable):
All - has never worked out of the box in Fedora.
Steps to Reproduce:
1. Try to dim backlight using either keys or gnome control.
Nothing happens (unless using patched DSDT)
Backlight should be adjustable.
The backlight dimmer works out of the box using the latest (9.10) Ubuntu release - I tried it using their live CD. So there should be a viable solution.
Hardware: Sony Vaio VGN-FW290 (and apparently others)
Video: ATI Technologies Inc Mobility Radeon HD 3650
I don't really know if this is an ACPI problem or a Kernel problem.
Changed component to kernel based on note in bug report 549074
I'm seeing this issue fixed with the current kernel 188.8.131.52-67.fc12.x86_64 - very nice.