Merge pull request #15 from deckerego/i2s_audio

I2S Audio Support

README.md

@@ -18,13 +18,12 @@ Installation
 
 I'm assuming that you are starting with the Raspian Minimal Linux distribution. NOOBS or the like also works, but Raspian Minimal is small enough to fit on a 2GB microSD card. To install the hack-clock distribution on top of it:
 
-1. Make sure your Raspberry Pi is up to date with the latest packages & firmware.
-2. Enable I2C as described in Adafruit's tutorial at https://learn.adafruit.com/adafruits-raspberry-pi-lesson-4-gpio-setup/configuring-i2c
+1. Make sure your Raspberry Pi is up to date with the latest packages & firmware with `sudo apt-get update; sudo apt-get dist-upgrade`
+2. Enable I2C by executing `sudo raspi-config` as described in Adafruit's tutorial: https://learn.adafruit.com/adafruits-raspberry-pi-lesson-4-gpio-setup/configuring-i2c
 3. Add the necessary Python and GStreamer dependencies using `sudo apt-get install wiringpi python-setuptools python-pip python-dev python-dateutil python-smbus gstreamer0.10-x gstreamer-tools gstreamer0.10-plugins-base gstreamer0.10-plugins-good gstreamer0.10-plugins-bad python-gst0.10`
 4. Install hack-clock via `dpkg -i http://hackclock.deckerego.net/downloads/python-hackclock_2.0-beta-1_all.deb`
-5. Install hack-clock's Python dependencies using `sudo pip install -r /usr/share/doc/hack-clock/requirements.txt`
-6. Tweak `/etc/hack-clock.conf` and `/etc/default/hack-clock` to fit your needs (GPIO pins, correct weather station, etc.)
-7. Start the app by executing `sudo service hack-clock start`
+5. Tweak `/etc/hack-clock.conf` and `/etc/default/hack-clock` to fit your needs (GPIO pins, correct weather station, etc.)
+6. Reboot your Pi or start the app by executing `sudo service hack-clock start`
 
 
 Usage

debian/python-hackclock.postinst

@@ -1,3 +1,37 @@
 #!/bin/bash
 
+BOOT_CONFIG=/boot/config.txt
+MOD_CONFIG=/etc/modules
+
+# Fix ownership in home directory after installing
 chown -R pi:pi /home/pi/hack-clock
+
+# Install those Python modules that only exist via pip
+echo "Installing missing Python modules..."
+pip install -r /usr/share/doc/hack-clock/requirements.txt
+
+# Set the hifiberry-dac i2s module
+echo "Installing I2S audio..."
+if [ -e $BOOT_CONFIG ] && grep -q "^dtoverlay=hifiberry-dac$" $BOOT_CONFIG; then
+    echo "hifiberry already installed"
+else
+    echo "dtoverlay=hifiberry-dac" | sudo tee -a $BOOT_CONFIG
+fi
+
+# Enable (optional) i2s-mmap to get rid of popping and set volumes
+if [ -e $BOOT_CONFIG ] && grep -q "^dtoverlay=i2s-mmap$" $BOOT_CONFIG; then
+    echo "i2s-mmap already installed"
+else
+    echo "dtoverlay=i2s-mmap" | sudo tee -a $BOOT_CONFIG
+fi
+
+# Make sure old audio is disabled
+if [ -e $BOOT_CONFIG ] && grep -q -E "^dtparam=audio=on$" $BOOT_CONFIG; then
+    echo "Commenting out dtparam=audio=on in $BOOT_CONFIG"
+    sudo sed -i "s|^dtparam=audio=on$|#dtparam=audio=on|" $BOOT_CONFIG &> /dev/null
+elif [ -e $MOD_CONFIG ] && grep -q "^snd-bcm2835" $MOD_CONFIG; then
+    echo "Commenting out snd-bcm2835 in $MOD_CONFIG"
+    sudo sed -i "s|^snd-bcm2835|#snd-bcm2835|" $MOD_CONFIG &> /dev/null
+fi
+
+echo "Please reboot your Raspberry Pi!"

etc/asound.conf

@@ -0,0 +1,33 @@
+pcm.hifiberry {
+  type hw card 0
+}
+
+pcm.!default {
+  type plug
+  slave.pcm "softvol"
+}
+
+pcm.dmixer {
+  type dmix
+  ipc_key 1024
+  slave {
+    pcm "hifiberry"
+    channels 2
+  }
+}
+
+ctl.dmixer {
+  type hw
+  card 0
+}
+
+pcm.softvol {
+  type softvol
+  slave {
+    pcm "dmixer"
+  }
+  control {
+    name "Master"
+    card 0
+  }
+}

etc/default/hack-clock

@@ -3,3 +3,6 @@ BUTTON_BCM_PIN=(23 24)
 
 # The pins (using the Broadcom numbering scheme) to be used for switches (output)
 SWITCH_BCM_PIN=(25)
+
+# Volume level to feed to ALSA SoftVol
+MASTER_VOLUME='75%'

etc/init.d/hack-clock

@@ -32,6 +32,11 @@ SCRIPTNAME=/etc/init.d/$NAME
 # and status_of_proc is working.
 . /lib/lsb/init-functions
 
+set_volume()
+{
+  amixer set Master -- "$MASTER_VOLUME"
+}
+
 #
 # Some dependencies can only be provided by PIP, check them
 #

setup.py

@@ -17,7 +17,7 @@ def all_files(newroot, oldroot):
     return fdtuples
 
 base_data_files = [
-    ('/etc',    ['etc/hack-clock.conf']),
+    ('/etc',    ['etc/hack-clock.conf', 'etc/asound.conf']),
     ('/etc/init.d',    ['etc/init.d/hack-clock']),
     ('/etc/default',    ['etc/default/hack-clock']),
     ('/usr/share/doc/hack-clock', ['README.md', 'LICENSE', 'MANIFEST', 'requirements.txt'])