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Script to control keyboard backlight brightness on a Chromebook Pixel running Ubuntu. Includes extra bits like restore old session value on boot, dim keyboard on screen lock, restoring value when resuming from suspend, and so on. Relies on kernel module acpi_call (instructions below).
#!/bin/sh
# This script will install the files below.
# Please look through them first so you know what will happen.
# Install by running this command:
# curl -fL https://gist.githubusercontent.com/stefansundin/7003429/raw/install-kbd-backlight.sh | sh
# Uninstall with:
# sudo rm /opt/kbd-{backlight,lock}.sh /etc/pm/sleep.d/70-kbd-backlight
# rm ~/.config/autostart/kbd-{backlight,lock}.sh.desktop
echo
echo "Installing /opt/kbd-backlight.sh"
echo " /opt/kbd-lock.sh"
echo " /etc/pm/sleep.d/70-kbd-backlight"
echo " $HOME/.config/autostart/kbd-backlight.sh.desktop"
echo " and $HOME/.config/autostart/kbd-lock.sh.desktop"
echo
echo Please provide your sudo password if prompted.
echo
sudo curl -fL -o /opt/kbd-backlight.sh https://gist.githubusercontent.com/stefansundin/7003429/raw/kbd-backlight.sh
echo
sudo curl -fL -o /opt/kbd-lock.sh https://gist.githubusercontent.com/stefansundin/7003429/raw/kbd-lock.sh
echo
sudo curl -fL -o /etc/pm/sleep.d/70-kbd-backlight https://gist.githubusercontent.com/stefansundin/7003429/raw/z-70-kbd-backlight
echo
sudo chmod 755 /opt/kbd-backlight.sh /opt/kbd-lock.sh /etc/pm/sleep.d/70-kbd-backlight
sudo sed -i "s/USER=username/USER=$USER/g" /etc/pm/sleep.d/70-kbd-backlight
cat > $HOME/.config/autostart/kbd-backlight.sh.desktop << EOF
[Desktop Entry]
Type=Application
Exec=/opt/kbd-backlight.sh boot
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name=Keyboard backlight (restore on login)
Comment=https://gist.github.com/stefansundin/7003429/
EOF
cat > $HOME/.config/autostart/kbd-lock.sh.desktop << EOF
[Desktop Entry]
Type=Application
Exec=/opt/kbd-lock.sh
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name=Keyboard backlight (dim on lock)
Comment=https://gist.github.com/stefansundin/7003429/
EOF
cat << EOF
Done.
Instructions for installing acpi_call:
sudo apt-get install git build-essential
git clone https://github.com/mkottman/acpi_call.git
cd acpi_call
make
sudo make install
sudo depmod
sudo modprobe acpi_call
sudo vim /etc/modules
acpi_call
You may then remove the acpi_call directory.
Note that you may have to recompile acpi_call when you update your kernel,
but probably not for minor updates.
Make acpi_call usable without sudo:
sudo chmod 666 /proc/acpi/call
sudo vim /etc/rc.local
chmod 666 /proc/acpi/call
You may then try changing the keyboard backlight value with:
You can now adjust the brightness with this command:
echo "\_SB.KBLT.KBCM 0" > /proc/acpi/call
or: /opt/kbd-backlight.sh 0
Use 100 to turn it fully on again. Use a value in between to adjust the brightness.
I recommend that you set your keyboard shortcuts in CCSM instead of the normal
keyboard shortcut manager, because many shortcuts set there will just stop
working after reboot. Be *very* careful with this tool!!!
sudo apt-get install compizconfig-settings-manager
ccsm
Enable the 'Commands' plugin and set these commands:
/opt/kbd-backlight.sh up
/opt/kbd-backlight.sh down
/opt/kbd-backlight.sh 100
/opt/kbd-backlight.sh 0
And then the key bindings:
<Alt>F7
<Alt>F6
<Shift><Alt>F7
<Shift><Alt>F6
Uninstall with:
sudo rm /opt/kbd-{backlight,lock}.sh /etc/pm/sleep.d/70-kbd-backlight
rm ~/.config/autostart/kbd-{backlight,lock}.sh.desktop
You may also want to remove your keyboard shortcuts in CCSM.
I recommend Chromebook users to also look at my other gist for mapping the
function keys with Xmodmap: https://gist.github.com/stefansundin/6987698
Donations are welcome at http://stefansundin.com/donate (PayPal)
(scroll up and read all output)
EOF
#!/bin/bash
# Script to control keyboard backlight brightness on a Chromebook Pixel running Ubuntu.
# The current brightness value is stored in ~/.kbd-backlight-value.
# sudo curl -fL -o /opt/kbd-backlight.sh https://gist.githubusercontent.com/stefansundin/7003429/raw/kbd-backlight.sh
if [ ! -f ~/.kbd-backlight-value ]; then
echo "First run: creating $HOME/.kbd-backlight-value"
echo 100 > ~/.kbd-backlight-value
fi
read val < ~/.kbd-backlight-value
echo Current value: $val
if [[ -z $val || $val == *[!0-9]* ]]; then
echo "Value is not a number, assuming 100"
val=100
fi
if [ -z "$1" ]; then
echo No argument, restoring stored value
elif [ "$1" == "fade" ]; then
for i in $(seq 0 $val); do
echo "\_SB.KBLT.KBCM $i" > /proc/acpi/call
sleep 0.1
done
elif [ "$1" == "up" ]; then
val=$(($val+10))
elif [ "$1" == "down" ]; then
val=$(($val-10))
elif [ "$1" == "dim" ]; then
for i in $(seq $val -1 20); do
echo "\_SB.KBLT.KBCM $i" > /proc/acpi/call
sleep 0.05
done
exit 0
elif [ "$1" == "boot" ]; then
for i in $(seq 100 -1 $val); do
echo "\_SB.KBLT.KBCM $i" > /proc/acpi/call
sleep 0.05
done
exit 0
else
val=$1
fi
if [ "$val" -gt "100" ]; then
val=100
elif [ "$val" -lt "0" ]; then
val=0
fi
echo New value: $val
echo "\_SB.KBLT.KBCM $val" > /proc/acpi/call
echo $val > ~/.kbd-backlight-value
#!/bin/bash
# Script to monitor when the computer is locked and dim the keyboard backlight.
# sudo curl -fL -o /opt/kbd-lock.sh https://gist.githubusercontent.com/stefansundin/7003429/raw/kbd-lock.sh
dbus-monitor --session "type='signal',interface='org.gnome.ScreenSaver',member='ActiveChanged'" | (
while true; do
read x
if [ "$x" == "boolean true" ]; then
/opt/kbd-backlight.sh dim
elif [ "$x" == "boolean false" ]; then
/opt/kbd-backlight.sh
fi
sleep 1
done )
#!/bin/sh
# Restore keyboard backlight brightness on resume from suspend.
# The only reason this file has a "z-" prefix on Github is to make it appear below kbd-backlight.sh.
# sudo curl -fL -o /etc/pm/sleep.d/70-kbd-backlight https://gist.githubusercontent.com/stefansundin/7003429/raw/z-70-kbd-backlight
USER=username #EDIT THIS
case "$1" in
resume|thaw)
su $USER -c "/opt/kbd-backlight.sh fade"&
;;
esac
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