On 15.07.2012 23:03, Anand Joseph wrote:
I am working on building a multi-channel USB audio device using the PIC32MX2 series with dual WM8731 audio codecs. The goal is a low cost 4 channel USB audio device. While this might not be the best combination for multi-channel audio, I do not have a better solution as the XMOS series is not easily available in India. I would like to know the status of USB audio class 2 support in ALSA and is there anyway I can contribute. I did go through the USB specifications for audio class 2 devices, but an idea of the implementation in ALSA would help in writing the firmware.
UAC2 is mostly supported in ALSA since a while. Things that are missing are exotic features like complex clock infrastructure handling and some mixer extension units that haven't been observed in the wild yet.
In any case, the support that is there already is more than enough to support a simple streaming device like the one you have in mind.
Let us know how your project goes and if you encounter any problems with the drivers.
Daniel