50-laptop-switch-display.rules

# Switch the input of the monitor when we detect the logitech mouse is removed
ACTION=="remove", ENV{ID_MODEL}=="Gaming_Mouse_G402", RUN+="/usr/local/bin/ddc-display.sh 1"

50-pc-switch-display.rules

# Switch the input of the monitor when we detect the logitech mouse is removed
ACTION=="remove", ENV{ID_MODEL}=="Gaming_Mouse_G402", RUN+="/usr/local/bin/ddc-display.sh 2"

ddc-display.sh

#!/bin/sh

# Set the input for the monitor using ddcutil. Requires that the user is
# in the i2c group. Input 1 for the gaming pc, 2 for the laptop dock.

main() {
    case "$1" in
        1 )
            # Display port (gaming PC)
            INPUT="0x0f"
            ;;
        2 )
            # Mini display port (laptop dock)
            INPUT="0x10"
            ;;
        * )
            echo "Unknown display $1"
            return 1
            ;;
    esac

    # 60 is the "change input" feature
    ddcutil --bus=5 setvcp 60 "$INPUT"
    return 0
}

main "$@"