ALSA
From ArmadeusWiki
This page will summarize the informations to use ALSA on your Armadeus boards.
Introduction
ALSA stands for Advanced Linux Sound Architecture and provides audio and MIDI functionality to the Linux operating system. Everyone wanting to write portable & state of the art Linux applications dealing with sound should consider using ALSA.
ALSA Soc
On the APF boards we are going to use Embedded version of ALSA: ALSA Soc ->
- http://opensource.wolfsonmicro.com/node/6
- http://www.rpsys.net/openzaurus/patches/alsa/info.html
- http://alsa-project.org/main/index.php/ASoC
nodes creation
in /dev/snd
mknod controlC0 c 116 0 mknod pcmC0D0c c 116 24 mknod pcmC0D0p c 116 16
Installation
- On your Host select ALSA compilation in Linux configuration:
[armadeus]$ make linux-menuconfig Device Drivers ---> Sound ---> <M> Sound card support Device Drivers ---> Sound ---> Advanced Linux Sound Architecture ---> <M> Advanced Linux Sound Architecture Device Drivers ---> Sound ---> Advanced Linux Sound Architecture ---> ALSA ARM devices ---> <M> IMX TSC2102 alsa driver
<M> Advanced Linux Sound Architecture
< > Sequencer support (NEW)
<M> OSS Mixer API
<M> OSS PCM (digital audio) API
[*] OSS PCM (digital audio) API - Include plugin system (NEW)
[ ] Dynamic device file minor numbers (NEW)
[*] Support old ALSA API (NEW)
[ ] Verbose procfs contents (NEW)
[ ] Verbose printk
[ ] Debug
[ ] Debug detection
[ ] Enable PCM ring buffer overrun/underrun debugging (NEW)
Generic devices --->
ALSA ARM devices --->
USB devices --->
System on Chip audio support --->
- in Buildroot configuration, select the user space packages for ALSA:
[armadeus]$ make menuconfig
Package Selection for the target-> Audio libraries:
--- Audio libraries and applications
[*] alsa-lib
[*] alsa-utils
ALSA utils selection --->
[ ] asterisk
[*] aumix
[ ] libmad
....
in ALSA utils selection ---> [*] alsaconf [*] alsactl [*] alsamixer [ ] amidi [*] amixer [*] aplay [ ] arecord [ ] iecset [ ] aconnect [ ] aplaymidi [ ] arecordmidi [ ] aseqdump [ ] aseqnet [*] speaker-test
- save your configuration and rebuild your rootfs:
[armadeus]$ make
- after reflashing your rootfs on your board, you can load ALSA drivers:
modprobe soundcore modprobe snd modprobe snd-timer modprobe snd-page-alloc modprobe snd-pcm modprobe snd-pcm-oss modprobe snd-mixer-oss
Only if MIDI sequencer used:
modprobe snd-seq modprobe snd-seq-device
Specific to DevFull:
modprobe spi_imx modprobe snd-imx-alsa-tsc2102
Test
# aplay -lL # aplay -vDhw:0,0 /usr/share/sounds/alsa/Side_Left.wav
Note: the audio file Side_Left.wav can be copied from your host PC
