Hello pals,
I am having problems in adjusting the screen brightness on
Dell Studio 1558 laptop with Debian Squeeze and intel graphics. Pressing the
corresponding Fn keys doesn't change the brightness and gives the following
error:
$ dmesg
...
[ 833.240055] ACPI: Failed to switch the brightness
[ 833.616022] ACPI: Failed to switch the brightness
[ 2182.884115] ACPI: Failed to switch the brightness
[ 2183.107576] ACPI: Failed to switch the brightness
I've tried "echo 10 >
/sys/devices/virtual/backlight/dell_backlight/brightness" without result.
The same with other values.
The file /proc/acpi/video/GFX0/DD01/brightness contains the line "<not
supported>".
There is a bug reported for Ubuntu in:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/568611
There is a patch offered there but I couldn't make it work on latest stable
kernel from kernel.org and there are no instructions available.
Any ideas?
Thanks in advance
Martín
