Introduction

brillo controls the brightness of backlight and LED devices on Linux.

Notable features include:

• Automatic best controller detection
• Smooth transitions and natural brightness adjustments
• Ability to save and restore brightness across boots
• Directly using sysfs to set brightness without relying on X
• Unprivileged access with no new setuid binaries
• Containment with AppArmor

For detailed usage, please refer to the man page.

Installation

From source

Building the manpage requires go-md2man.

To build and install the binary, manpage, and udev rule:

$ make
# make install

Users in the configured group (video by default) will be able to adjust the brightness. An alternative group can be configured using the GROUP variable:

# make install GROUP=_brillo

If you would prefer to allow any user, regardless of group, to change the brightness, you may install the binary as setgid:

# make install.setgid GROUP=_brillo

To additionally install the apparmor profile:

# make install.apparmor

To additionally install the polkit rule:

# make install.polkit

Note: the install* targets use the PREFIX and DESTDIR variables to compose the installation path and generate configuration files.

Unprivileged Access

polkit

Active sessions can invoke brillo via pkexec to escalate priveleges.

Examples:

$ pkexec /usr/bin/brillo -O
$ pkexec /usr/bin/brillo -A 5

Note: this requires polkitd and (e)logind or ConsoleKit.

udev

brillo's udev rule grants necessary permissions to the video group for backlight and keyboard LED devices.

Users in these groups can modify values directly. Alternately, the binary may be installed as setgid so that any user may change the brightness.

Note: in this mode, stored brightness and minimum cap files will be in the user's cache home (typically "~/.cache").

See Also

clight: provides dimming based on ambient light and color correction based on location.

ddcci-driver-linux: exposes external monitor brightness in sysfs, so brillo can access them.

ddcutil: designed to control brightness and color correction for external monitors.

Copyright

Copyright (C) 2018-2019 Cameron Nemo, 2014 Fredrik Haikarainen

This is free software, see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE