#!/usr/bin/env sh

HCIATTACH='/usr/bin/hciattach'

if /usr/bin/grep --quiet 'raspberrypi,4' '/proc/device-tree/compatible'; then
  BDADDR=''
else
  SERIAL=$(< '/proc/device-tree/serial-number' /usr/bin/cut '-c9-')
  B1=$(/usr/bin/echo "${SERIAL}" | /usr/bin/cut '-c3-4')
  B2=$(/usr/bin/echo "${SERIAL}" | /usr/bin/cut '-c5-6')
  B3=$(/usr/bin/echo "${SERIAL}" | /usr/bin/cut '-c7-8')
  BDADDR=$(/usr/bin/printf 'b8:27:eb:%02x:%02x:%02x' $((0x$B1 ^ 0xaa)) $((0x$B2 ^ 0xaa)) $((0x$B3 ^ 0xaa)))
fi

# Bail out if the kernel is managing the Bluetooth modem initialisation
if ( /usr/bin/dmesg | /usr/bin/grep --extended-regexp --quiet "hci[0-9]+: BCM: chip" ); then
  # On-board bluetooth is already enabled
  exit 0
fi

UART0=$(/usr/bin/cat '/proc/device-tree/aliases/uart0')
SERIAL1=$(/usr/bin/cat '/proc/device-tree/aliases/serial1')

if [ "${UART0}" = "${SERIAL1}" ] ; then
  UART0_PINS=$(/usr/bin/wc --bytes '/proc/device-tree/soc/gpio@7e200000/uart0_pins/brcm\,pins' | /usr/bin/cut --delimiter=' ' --fields='1')
  if [ "${UART0_PINS}" = "16" ] ; then
    "${HCIATTACH}" '/dev/serial1' bcm43xx 3000000 flow - "${BDADDR}"
  else
    "${HCIATTACH}" '/dev/serial1' bcm43xx 921600 noflow - "${BDADDR}"
  fi
else
  "${HCIATTACH}" '/dev/serial1' bcm43xx 460800 noflow - "${BDADDR}"
fi