Ubuntu
linux package

  1. Bug #423296
  2. Comment #6

Comment 6 for bug 423296

Revision history for this message
Arnd (arnd-arndnet) wrote :

@Stefan Bader

> Have you tried the following?

> 1. Add "options thinkpad_acpi brightness_enable=1" to /etc/modprobe.d/acpi-video.conf
> 2. Update the initrd "sudo update-initramfs -u"
> 3. Add "acpi_backlight=vendor" to the kernel commandline (in /boot/grub/menu.lst)

This "somehow" works, but is definitely a workaround and NOT the correct solution.
Now there is /proc/acpi/ibm/brightness, and I can adjust the brightness manually by echoing "up" and
"down" into this file, (keys did not work) Dmesg reports:
[ 1633.052410] thinkpad_acpi: detected a 16-level brightness capable ThinkPad

However, I want to make clear that the general ACPI video module works as intended in 2.6.28-15.49 AND also the 2.6.30 mainline builds! There is a specific problem with 2.6.28-15.51.