Control intel backlight on FreeBSD (and OpenBSD)
openbsd
1This allows to control the backlight level on certain Intel(R) GPUs,
2including i915.
3
4This has been taken from intel-gpu-tools which can be found
5here: http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/
6
7Originally ported to FreeBSD by "emmex" of the FreeBSD forums.
8
9FreeBSD Build:
10 pkg install libpciaccess libdrm
11 make
12 make install
13
14OpenBSD Build:
15 make
16 make install
17
18(this installs intel_backlight setuid root, so any user can execute it).
19
20Usage:
21 $ intel_backlight
22 current backlight value: 30% (281/937)
23 $ intel_backlight 50
24 current backlight value: 15% (141/937)
25 set backlight to 50% (469/937)
26 $ intel_backlight incr
27 current backlight value: 50% (469/937)
28 set backlight to 51% (478/937)
29 $ intel_backlight incr
30 current backlight value: 51% (478/937)
31 set backlight to 60% (562/937)
32 $ intel_backlight incr
33 current backlight value: 60% (562/937)
34 set backlight to 70% (656/937)
35 $ intel_backlight decr
36 current backlight value: 70% (656/937)
37 set backlight to 60% (562/937)
38 $ intel_backlight decr
39 current backlight value: 60% (562/937)
40 set backlight to 51% (478/937)
41
42The included example allows adjusting brightness automatically based on the
43input of the isl driver (currently not part of standard FreeBSD).
44
45Usage:
46 ./isl_backlight.sh &
47
48
49OpenBSD Notes:
50Requires a kernel capable of concurrent opening of /dev/xf86, via
51machdep.allowaperture=3.