darkarc/ddcrelight

Automatic monitor brightness adjustment for Linux using yoctopuce light sensor hardware

ddcrelight

Requirements

• A yoctopuce light sensor (https://www.yoctopuce.com)
• ddcutil

Setup

A udev rule is likely required to allow the tool to run as non-root. The following can be added as the file /etc/udev/rules.d/50-yoctopuce.rules:

# udev rules to allow write access to all users for Yoctopuce USB devices
SUBSYSTEM=="usb", ATTR{idVendor}=="24e0", MODE="0666"

Additionally, udev rules must be configured for ddcutil to operate without root permissions:

https://www.ddcutil.com/i2c_permissions/

Then a daemon should be setup:

ddcrelight.service:

[Unit]
Description=Update monitor brightness intelligently using light sensors.

[Service]
ExecStart=<path-to-script>/ddcrelight daemon
Restart=on-failure
RestartSec=5

[Install]
WantedBy=default.target

Usage

usage: ddcrelight [-h] {daemon,set-brightness} ...

Update monitor brightness intelligently.

positional arguments:
  {daemon,set-brightness}
                        sub-command help
    daemon              run the daemon
    set-brightness      update the brightness database for the current light level

options:
  -h, --help            show this help message and exit