DDC (Display Data Channel) switcher

ddc.sh

#!/usr/bin/env bash

# This script acts as a switcher between video inputs of a monitor (https://en.wikipedia.org/wiki/Display_Data_Channel).
# It allows to switch to a custom video input and get back in one key pressing.
#
# Dependencies:
# 1. ddcutil

# Example:
#
# I use this script with two DELL U2415 which are connected through DisplayPort to Dell E-Port Plus.
#
# Example shortcut:
#
# First press -> Ctrl+Alt+Num9 -> /opt/toolset/ddc.sh 1 4 -> switch monitor1 to input4
# Second press -> Ctrl+Alt+Num9 -> /opt/toolset/ddc.sh 1 4 -> switch monitor1 to input2 (where I usually work)


MONITOR="$1"
INPUT="$2"

if [ ! "$MONITOR" ] || [ ! "$INPUT" ];then
    echo "ERROR: Usage $0 1|2 1|2|3|4"
    exit 1
fi

CURRENT_INPUT=$(printf "0%s\n" $(ddcutil -t -d "$MONITOR" getvcp 0x60 2>/dev/null  | cut -d " " -f 4))

case "$INPUT" in
  1)
    INPUT_CODE="0x0f"
    ;;
  2)
    INPUT_CODE="0x10"
    ;;
  3)
    INPUT_CODE="0x11"
    ;;
  4)
    INPUT_CODE="0x12"
    ;;
esac


if [ "$CURRENT_INPUT" = "0x10" ];then
    # If we are on the primary input - switch to the specific input
    ddcutil -d "$MONITOR" setvcp "0x60" "$INPUT_CODE" 2>/dev/null
else
    # If we are not on the primary input - switch back to the primary input
    ddcutil -d "$MONITOR" setvcp "0x60" "0x10" 2>/dev/null
fi