LCD Brightness

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LCD Brightness

This worked for my X61:

Once your brightness keys work, you can set the brightness by writing to the procfs:

# echo 100 > /proc/acpi/video/VID1/LCD0/brightness

using a script and acpid events. However this may lead to a bug (screen flickers) described on the Debian mailing list [[1]]. This bug is related to the X server as it does not occur on the tty1. To fix it change your xrandr backlight control to native:

$ $xrandr --output LVDS --set BACKLIGHT_CONTROL native

For my X61, these following scripts from this japanese site helped:

% cat /etc/acpi/video_brightnessdown.sh
#!/bin/sh
xbacklight -dec 10%

% cat /etc/acpi/video_brightnessup.sh
#!/bin/sh
xbacklight -inc 10%

2.6.26 kernel

If you are using a 2.6.26 kernel, the backlight does not work with thinkpad-acpi.

Modify the kernel config by first disabling CONFIG_THINKPAD_ACPI_VIDEO and then enabling both CONFIG_VIDEO_OUTPUT_CONTROL and CONFIG_ACPI_VIDEO [2] While you are at it, be sure to read the well-written help sections for the kernel config settings :)