ShiftLock LED as HDDLED on Dell XPS 13

The following HowTo will show how to use the ShiftLock LED on the DELL XPS 13 as a HardDrive LED. You need a Linux distribution with systemd. The following dependencies need to be installed:

kbd
xorg-setxkbmap

#!/bin/bash
# save this file as pcfreakled without extension
# and make it executable (chmod +x)

#check dependencies
command -v setxkbmap >/dev/null 2>&1 || { echo >&2 "Script requires setxkbmap but it is not installed.Aborting."; exit 1; }
command -v setleds   >/dev/null 2>&1 || { echo >&2 "Script requires setleds but it is not installed.Aborting."; exit 1; }

# console
CONSOLE=/dev/console

# disable caps lock key
# This can also be done within Gnome but here is also a good place
setxkbmap -option ctrl:nocaps  >/dev/null 2>&1

# Check interval seconds
CHECKINTERVAL=0.1

#indicator to use [caps, num, scroll]
INDICATOR=caps

getVmstat() {
#  cat /proc/vmstat|
   egrep "pgpgin|pgpgout" /proc/vmstat 
}
#turn led on
function led_on()
{
    setleds -L +${INDICATOR} < ${CONSOLE} >/dev/null 2>&1
}
#turn led off
function led_off()
{
    setleds -L -${INDICATOR} < ${CONSOLE} >/dev/null 2>&1
}
# initialise variables
NEW=$(getVmstat)
OLD=$(getVmstat)
## 
while [ 1 ] ; do
  sleep $CHECKINTERVAL # slowdown a bit
  # get status 
  NEW=$(getVmstat)
  #compare state
  if [ "$NEW" = "$OLD" ]; then  
    led_off ## no change, led off
  else
    led_on  ## change, led on
  fi
  OLD=$NEW  
done

[Unit]
Description=PCFreaks Dell XPS13 DriveLED

[Service]
Type=simple
ExecStart=/usr/lib/systemd/scripts/pcfreakled

[Install]
WantedBy=multi-user.target

Copy pcfreakled to

/usr/lib/systemd/scripts/pcfreakled

and make it executable

sudo chmod +x /usr/lib/systemd/scripts/pcfreakled

Copy pcfreakled.service to

/usr/lib/systemd/system/pcfreakled.service

sudo systemctl enable pcfreakled.service

sudo systemctl start pcfreakled.service

sudo systemctl status pcfreakled.service

sudo systemctl enable pcfreakled.service

Use the following script

#!/bin/bash

# check if root
if [ "$(id -u)" != "0" ]; then
	echo "please run this script as root or with sudo"
	exit
fi

#very simple install/uninstall script for PCFreak HDD LED systemd service
myfile=./pcfreakled
myfiletarget=/usr/lib/systemd/scripts/pcfreakled
mydaemon=./pcfreakled.service
mydaemontarget=/usr/lib/systemd/system/pcfreakled.service
myservice=pcfreakled.service
myserviceshort=pcfreakled

case "$1" in
	install)
	echo "placing $myfile in $myfiletarget..."
	cp "$myfile" "$myfiletarget"
	echo "...done!"
	echo "placing $mydaemon in $mydaemontarget..."
	cp "$mydaemon" "$mydaemontarget"
	echo "...done!"
	systemctl daemon-reload
	echo "You can now enable/disable/start $myservice with systemctl command!"
	exit
	;;

	remove)
	echo "Trying to stop $myservice..."
	systemctl stop $myservice
	echo "Trying to disable $myservice..."
	systemctl disable $myservice
	echo "Trying to kill all remaining processes..."
	killall $myserviceshort
	echo "Removing $myfiletarget..."
	rm "$myfiletarget"
	echo "...done!"
	echo "Removing $mydaemontarget..."
	rm "$mydaemontarget"
	echo "...done!"
	echo "Uninstall complete!"
	exit
	;;

	*)
	echo "run with parameter install or remove"
	exit
	;;
esac

and make it executable

chmod +x ./setup

then execute

sudo ./setup install
<code>

for installation or

<code>
sudo ./setup remove

for uninstallation.