NAME

intel_backlight —

control backlight on various modern Intel GPUs

SYNOPSIS

intel_backlight [decr | incr | n]

This utility allows to control the brightness of the backlight on certain Intel GPUs, including i915.

The current backlight value is reported every time the program is run. Additionally, if the argument are invalid then a help message is shown.

The backlight brightness levels that decr and incr operate on are as follows: 1, 2, 4, 6, 9, 12, 16, 20, 25, 30, 36, 43, 51, 60, 70, 80, 90, 100.

The options are as follows:

decr: Decrease the backlight value to the nearest brightness level.
incr: Increase the backlight value to the nearest brightness level.
n: Change the backlight value to n where n should be between 0 and 100. Providing any other integer results in setting the backlight back to the default value of 100.

/usr/local/share/examples/intel-backlight/asmc_backlight.sh: An example of a script adjusting brightness automatically based on the input of the MacBook asmc(4) light sensor driver.
/usr/local/share/examples/intel-backlight/isl_backlight.sh: An example of a script adjusting brightness automatically based on the input of the isl(4) driver, which is currently not part of standard FreeBSD.

The intel_backlight utility exits 0 on success, and >0 if an error occurs.

The command may fail for any of the following reasons:

Couldn't initialize PCI system: Device not configured: The user does not have required permissions to execute intel_backlight as it probably hasn't got the setuid bit set during installation. The solution is either to reinstall this program or to run the command as root.

See intel_chipset.h in the source distribution of intel_backlight for a list of supported chipsets.

Originally ported to FreeBSD by emmex of the FreeBSD forums.

intel_backlight is based on the code that has been taken from the project developing test suite and tools for DRM/KMS drivers, which can be found here: http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/

This manual page was written by Mateusz Piotrowski <0mp@FreeBSD.org>.