[alsa-devel] [PATCH] ASoC: Tegra: Add support of tegra boards based on ALC5632 codec

Mark Brown broonie at opensource.wolfsonmicro.com
Wed Nov 23 23:46:22 CET 2011

On Wed, Nov 23, 2011 at 02:30:12PM -0800, Stephen Warren wrote:
> Mark Brown wrote at Wednesday, November 23, 2011 2:59 PM:

> > > That said, while these values are constant right now, I think they won't
> > > always be; I think we'll need to switch between DSP mode for mono and
> > > I2S mode for stereo here; at least I /think/ that's what I remember our
> > > downstream drivers doing...

> > That would be a surprising restriction for your hardware to have.  From
> > the CODEC point of view it really doesn't care at all, all the interface
> > formats are interchangable.

> I believe Tegra20 HW "hard-codes" the channel count to 2 in I2S mode,
> And hence always pulls 2 channels from the FIFO for each frame. So, I2S
> can't do mono. This appears to be fixed in Tegra30. Tegra can be
> surprising:-)

If it's got that restriction why not run it in PCM mode all the time?

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