Automatic connecting to Bluetooth joystick for Raspberry Pi

joystick-connect.sh

#!/bin/bash

###
### NOTE: add cron job that runs every minute using `crontab -e`:
###   * * * * * ~/joystick-connect.sh
###

# using a device ID is more secure, but using \t uses first available device
DEVICE='\t'
#DEVICE='XX:XX:XX:XX:XX:XX'

JS='/dev/input/js0'

BUTTON_MAP="8,0,1,2,5,9,10,16,17,16,315,304,305,314,307,308,310,311,316,317,318,319,306,309,312,313"
BUTTON_CAL="8,1,0,127,127,-4194176,-4227201,1,0,127,127,4227201,4194176,1,0,127,127,2147483647,2147483647,1,0,127,127,2147483647,2147483647,1,0,0,0,2147483647,2147483647,1,0,0,0,2147483647,2147483647,1,0,0,0,2147483647,2147483647,1,0,0,0,2147483647,2147483647"

# if the joystick isn't connected, try to connect it
if [ ! -e ${JS} ]; then 
  echo -e "power on\nconnect ${DEVICE}\nquit\n" | bluetoothctl

  # wait for joystick driver to kick in before next step
  sleep 10
fi

# if the joystick is connected, ensure we're using the right calibration settings
if [ -e ${JS} ]; then

  jscal -q ${JS} | grep "${BUTTON_MAP}" &>/dev/null
  if [ $? -ne 0 ]; then
    echo "calibrating ${JS}"
    jscal -u ${BUTTON_MAP} ${JS}
    jscal -s ${BUTTON_CAL} ${JS}
  fi
fi