[alsa-devel] [RFC] [PATCH] ASoC: OMAP: full duplex mode fix

Janusz Krzysztofik jkrzyszt at tis.icnet.pl
Thu Aug 6 11:16:51 CEST 2009

Wednesday 05 August 2009 10:42:54 Jarkko Nikula wrote:
> On Wed, 5 Aug 2009 10:21:49 +0300
> Jarkko Nikula <jhnikula at gmail.com> wrote:
> > > If my analysis is correct, the best solution I can see would be
> > > starting McBSP transfer for one direction only, not both, so the
> > > opposite direction can be started when needed. That requires deeper and
> > > wider OMAP knowledge and a change in omap_mcbsp_start() API though. I
> > > am not in a position to deal with this myself, I'm afraid.
> >
> > I favor this change. Actually I remember I was thinking shortly to
> > change API of omap_mcbsp_start and _stop more than year back or so but
> > didn't find it necessary back then.
> >
> > I think change will be trivial. Basically two new arguments indicating
> > are the TX/RX active and let the first/last caller to deal with
> > sample-rate generator and frame sync activation/de-activation.
> I hacked a patch below. Can you test does it help?

Yes, it does. Works as expected in all possible combinations I have tried: 
start recording while playing, start playing while recording, start recording 
and playing simultaneously.

Tested-by: Janusz Krzysztofik <jkrzyszt at tis.icnet.pl>

More information about the Alsa-devel mailing list