setup.sh

#!/usr/bin/env bash
pushd "$( dirname "${BASH_SOURCE[0]}" )" > /dev/null
RPI_SETUP_DIR="$( pwd )"

# Valid values for XMOS device
XMOS_DEVICE=
if [[ $# -ge 1 ]]; then
  XMOS_DEVICE=$1
else
  echo error: No device type specified.
  exit 1
fi

# Configure device-specific settings
case $XMOS_DEVICE in
  xvf3510)
    I2S_MODE=master
    I2S_CLK_DAC_SETUP=y
    ASOUNDRC_TEMPLATE=$RPI_SETUP_DIR/resources/asoundrc_vf_xvf3510
    ;;
  xvf3500)
    I2S_MODE=slave
    ASOUNDRC_TEMPLATE=$RPI_SETUP_DIR/resources/asoundrc_vf_stereo
    ;;
  xvf3100)
    I2S_MODE=slave
    ASOUNDRC_TEMPLATE=$RPI_SETUP_DIR/resources/asoundrc_vf
    ;;
  *)
    echo error: unknown XMOS device type $XMOS_DEVICE.
    exit 1
  ;;
esac

# Disable the built-in audio output so there is only one audio
# device in the system
sudo sed -i -e 's/^dtparam=audio=on/#dtparam=audio=on/' /boot/config.txt

# Enable the i2s device tree
sudo sed -i -e 's/#dtparam=i2s=on/dtparam=i2s=on/' /boot/config.txt

# Enable the I2C device tree
sudo raspi-config nonint do_i2c 1
sudo raspi-config nonint do_i2c 0

# Set the I2C baudrate to 100k
sudo sed -i -e '/^dtparam=i2c_arm_baudrate/d' /boot/config.txt
sudo sed -i -e 's/dtparam=i2c_arm=on$/dtparam=i2c_arm=on\ndtparam=i2c_arm_baudrate=100000/' /boot/config.txt

# Enable the SPI support
sudo raspi-config nonint do_spi 1
sudo raspi-config nonint do_spi 0

echo "Installing Raspberry Pi kernel headers"
sudo apt-get install -y raspberrypi-kernel-headers

echo "Installing the Python3 packages and related libs"
sudo apt-get install -y python3-matplotlib
sudo apt-get install -y python3-numpy
sudo apt-get install -y libatlas-base-dev

echo  "Installing necessary packages for dev kit"
sudo apt-get install -y libusb-1.0-0-dev libreadline-dev libncurses-dev

# Build I2S kernel module
PI_MODEL=$(cat /proc/device-tree/model | awk '{print $3}')
if [[ $PI_MODEL = 4 ]]; then
  I2S_MODULE_CFLAGS="-DRPI_4B"
fi

case $I2S_MODE in
  master)
    if [[ -z "$I2S_MODULE_CFLAGS" ]]; then
      I2S_MODULE_CFLAGS=-DI2S_MASTER
    else
      I2S_MODULE_CFLAGS="$I2S_MODULE_CFLAGS -DI2S_MASTER"
    fi
    ;;
  slave)
    # no flags needed for I2S slave compilation
    ;;
  *)
    echo error: I2S mode not known for XMOS device $XMOS_DEVICE.
    exit 1
  ;;
esac
I2S_BUILD_DIR=$RPI_SETUP_DIR/loader/i2s_$I2S_MODE
pushd $I2S_BUILD_DIR > /dev/null
if [[ -n "$I2S_MODULE_CFLAGS" ]]; then
  CMD="make CFLAGS_MODULE='$I2S_MODULE_CFLAGS'"
else
  CMD=make
fi
echo $CMD
eval $CMD
if [[ $? -ne 0 ]]; then
  echo "Error: I2S kernel module build failed"
  exit 1
fi

popd > /dev/null

# Move existing files to back up
if [[ -e ~/.asoundrc ]]; then
  chmod a+w ~/.asoundrc
  cp ~/.asoundrc ~/.asoundrc.bak
fi
if [[ -e /usr/share/alsa/pulse-alsa.conf ]]; then
  sudo mv /usr/share/alsa/pulse-alsa.conf  /usr/share/alsa/pulse-alsa.conf.bak
fi

# Check XMOS device for asoundrc selection.
if [[ -z "$ASOUNDRC_TEMPLATE" ]]; then
  echo error: sound card config not known for XMOS device $XMOS_DEVICE.
  exit 1
fi
cp $ASOUNDRC_TEMPLATE ~/.asoundrc

# Make the asoundrc file read-only otherwise lxpanel rewrites it
# as it doesn't support anything but a hardware type device
chmod a-w ~/.asoundrc

# Apply changes
sudo /etc/init.d/alsa-utils restart

# Create the script to run after each reboot and make the soundcard available
i2s_driver_script=$RPI_SETUP_DIR/resources/load_i2s_driver.sh
rm -f $i2s_driver_script

# Sometimes with Buster on RPi3 the SYNC bit in the I2S_CS_A_REG register is not set before the drivers are loaded
# According to section 8.8 of https://cs140e.sergio.bz/docs/BCM2837-ARM-Peripherals.pdf
# this bit is set after 2 PCM clocks have occurred.
# To avoid this issue we add a 1-second delay before the drivers are loaded
echo "sleep 1"  >> $i2s_driver_script

if [[ -z "$I2S_MODE" ]]; then
  echo error: I2S mode not known for XMOS device $XMOS_DEVICE.
  exit 1
fi

I2S_NAME=i2s_$I2S_MODE
I2S_MODULE=$RPI_SETUP_DIR/loader/$I2S_NAME/${I2S_NAME}_loader.ko
echo "sudo insmod $I2S_MODULE"                            >> $i2s_driver_script

echo "# Run Alsa at startup so that alsamixer configures" >> $i2s_driver_script	
echo "arecord -d 1 > /dev/null 2>&1"                      >> $i2s_driver_script	
echo "aplay dummy > /dev/null 2>&1"                       >> $i2s_driver_script

if [[ -n "$I2S_CLK_DAC_SETUP" ]]; then
  pushd $RPI_SETUP_DIR/resources/clk_dac_setup/ > /dev/null
  make
  popd > /dev/null
  i2s_clk_dac_script=$RPI_SETUP_DIR/resources/init_i2s_clks.sh
  rm -f $i2s_clk_dac_script
  echo "sudo $RPI_SETUP_DIR/resources/clk_dac_setup/setup_mclk"         >> $i2s_clk_dac_script
  echo "sudo $RPI_SETUP_DIR/resources/clk_dac_setup/setup_bclk"         >> $i2s_clk_dac_script
  echo "python $RPI_SETUP_DIR/resources/clk_dac_setup/setup_dac.py"     >> $i2s_clk_dac_script
  echo "python $RPI_SETUP_DIR/resources/clk_dac_setup/reset_xvf3510.py" >> $i2s_clk_dac_script
fi

sudo apt-get install -y audacity
if [[ -n "$I2S_CLK_DAC_SETUP" ]]; then
  audacity_script=$RPI_SETUP_DIR/resources/run_audacity.sh
  rm -f $audacity_script
  echo "#!/usr/bin/env bash" >> $audacity_script
  echo "/usr/bin/audacity &" >> $audacity_script
  echo "sleep 5" >> $audacity_script
  echo "sudo $RPI_SETUP_DIR/resources/clk_dac_setup/setup_bclk >> /dev/null" >> $audacity_script
  sudo chmod +x $audacity_script
  sudo mv $audacity_script /usr/local/bin/audacity
fi


# Setup the crontab to restart I2S at reboot
rm -f $RPI_SETUP_DIR/resources/crontab
echo "@reboot sh $i2s_driver_script" >> $RPI_SETUP_DIR/resources/crontab
if [[ -n "$I2S_CLK_DAC_SETUP" ]]; then
  echo "@reboot sh $i2s_clk_dac_script" >> $RPI_SETUP_DIR/resources/crontab
fi
crontab $RPI_SETUP_DIR/resources/crontab

echo "To enable I2S, I2C and SPI, this Raspberry Pi must be rebooted."

popd > /dev/null