apt install ddccontrol i2c-tools
modprobe i2c-dev

např. manuální ovládání jasu

ddccontrol dev:/dev/i2c-5 -r 0x10 -w 50

apt install gddccontrol

https://unix.stackexchange.com/questions/189675/is-there-a-way-to-adjusts-the-brightness-of-the-monitor https://gitlab.com/ddcci-driver-linux/ddcci-driver-linux

https://blog.tcharles.fr/ddc-ci-screen-control-on-linux/