[LAU] Experience with rpi, wolfson audio card and JACK

[Simon Wise]

On 21/05/15 05:02, F. Silvain wrote:
> Hey hey everyone,
> has anyone tried the Wolfson audio card with JACK yet? It's a little difficult
> to find, since google doesn't distinguish between jack and JACK. :)
>
> A link to a relevant post somewhere will suffice. Thank you!

wolfsons work fine with alsa, I've used them for installations with puredata, a 
lot better to work with than the usb audio via the cruddy rpi usb.

jack uses alsa, so if jack is doing what you want on your rpi it will use the 
wolfsons just as easily.

I have only used the older (not +) ones, and needed some work to get the kernel 
and drivers set up. The kernel offered by wolfson was not working properly for a 
long time, but there were others available, and recent  third party updates also 
... see below.

A problem with the wolfsons, but not a problem in your case using jack/alsa, is 
that I have only been able to use them via alsa, I would also like to be able to 
set them as the default audio out directly from the GPU, to play audio along 
with video from the omx layer.

The alsa controls are very extensive, you have lots of control of in, out, 
clocking, dsp, mixing etc ... but this flexibility does mean that they are not 
simple plug and play.

I have all the required files for using them with older raspbian wheezy, but 
there is an updated kernel, source, drivers etc etc here ...

https://blog.georgmill.de/2015/02/18/update-for-wolfson-audio-card-on-raspberry-pi/

it is a more recent version, for more recent raspbian, than I used.

I have some messy, long-winded notes re all the alsa stuff, configurations etc 
... if you go with them ask here and I'll try to get them sorted out a bit so 
they are useful to others.

Simon