samsung nc110 brightness adjustment

#!/bin/bash

DEVICE=00:02.0

VALUES=(02 04 06 08 0c 10 20 40 60 80 a0 d0 f0)
DEFAULT=11

current=$(setpci -s $DEVICE F4.B)
current=${current,,}
case "$1" in
    set|reset)
        if [ -n "$2" ]; then
            new=${2,,}
            if [ "${#new}" -eq 1 ]; then
                new=0$new
            fi
        else
            new=${VALUES[DEFAULT]}
        fi
        tmp=$((0x$new))
        if [ $tmp -gt 1 ] && [ $tmp -lt 256 ]; then
            if setpci -s $DEVICE F4.B=$new >/dev/null 2>&1; then
                echo "Brightness set from 0x$current to 0x$new"
            else
                exit 2
            fi
        else
            echo "Incorrect brightness value: $new" >&2
            exit 1
        fi
        ;;
    up|down)
        for i in $(seq 0 $((${#VALUES[*]}-1))); do
            if [ "${VALUES[$i]}" == "$current" ]; then
                break
            fi
        done
        if [ "${VALUES[$i]}" != "$current" ]; then
            i=$DEFAULT
        fi
        case "$1" in
        up)
            i=$((i+1))
            if [ "$i" -eq "${#VALUES[*]}" ]; then
                echo "Brightness is already maximum"
            else
                 new=${VALUES[$i]}
                 $0 set $new >/dev/null 2>&1 && echo "Brightness increased from 0x$current to 0x$new"
            fi
            ;;
        down)
            i=$((i-1))
            if [ "$i" -eq "-1" ]; then
                echo "Brightness is already minimum"
            else
                 new=${VALUES[$i]}
                 $0 set $new >/dev/null 2>&1 && echo "Brightness decreased from 0x$current to 0x$new"
            fi
            ;;
        esac
        ;;
    *)
        echo "Current brightness is 0x$current"
        ;;
esac