From 80f78202b5102feff4c08216c44819397867924e Mon Sep 17 00:00:00 2001 From: Christian Heller Date: Sun, 16 Apr 2017 06:24:09 +0200 Subject: [PATCH] Improve backlight setting script. --- bin/w530_backlight.sh | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/bin/w530_backlight.sh b/bin/w530_backlight.sh index bce6b30..e9a0c6b 100755 --- a/bin/w530_backlight.sh +++ b/bin/w530_backlight.sh @@ -1,17 +1,31 @@ #!/bin/sh + # A very primitive backlight setter with a hardcoded backlight path, to replace # xbacklight which currently does not work on my system. -if ! echo "${1}" | egrep -q '^[0-9]+$'; then - echo 'Argument must be a number.' + +if ! echo "${1}" | egrep -q '^[0-9]+$' && ! [ "${1}" = "+" -o "${1}" = "-" ]; then + echo 'Argument must be a number, or "+", or "-".' exit 1 fi -percentage=${1} backlight_dir=/sys/class/backlight/intel_backlight max_brightness=$(cat "${backlight_dir}"/max_brightness) +target="${backlight_dir}"/brightness +fract=$(expr "${max_brightness}" / 100) +if [ "${1}" = "+" -o "${1}" = "-" ]; then + cur_brightness=$(cat "${backlight_dir}"/brightness) + brightness=$(expr "${cur_brightness}" "${1}" "${fract}") + if [ "${brightness}" -gt "${max_brightness}" ]; then + brightness="${max_brightness}" + elif [ "${brightness}" -lt "0" ]; then + brightness=0 + fi + sudo sh -c 'echo '"${brightness}"' > '"${target}" + exit 0 +fi +percentage=${1} if [ "${percentage}" = '100' ]; then - sudo sh -c 'echo '"${max_brightness}"' > '"${backlight_dir}"'/brightness' + sudo sh -c 'echo '"${max_brightness}"' > '"${target}" else - fract=$(expr "${max_brightness}" / 100) brightness=$(expr "${percentage}" \* "${fract}") - sudo sh -c 'echo '"${brightness}"' > '"${backlight_dir}"'/brightness' + sudo sh -c 'echo '"${brightness}"' > '"${target}" fi -- 2.30.2