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

[Stephen Warren]

Mark Brown wrote at Wednesday, November 23, 2011 2:59 PM:
> On Wed, Nov 23, 2011 at 01:50:39PM -0800, Stephen Warren wrote:
> > Leon Romanovsky wrote at Monday, November 21, 2011 1:08 PM:
...
> > Mark Brown wrote here:
> > > These should use the .dai_fmt member in the dai_link struct.
> 
> > Mark, I guess you mean that we should remove those two snd_soc_dai_set_fmt
> > calls, and just set .dai_fmt to a constant value? If so, that should be
> > applied to the other two Tegra machine drivers too.
> 
> Yes.
> 
> > 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:-)

> > > +MODULE_LICENSE("GPL");
> 
> > The comment at the top would imply "GPL v2", since no "or later" is
> > mentioned there. Yes, the existing Tegra code is probably wrong here too.
> 
> GPL v2 is the standard interpretation for GPL within the kernel given
> that that is the license of the kernel itself.  I'd only bother saying
> anything different if the license were different but it won't do any
> harm.

I mentioned this, because of the following in include/linux/module.h

* The following license idents are currently accepted as indicating free
* software modules
*
*      "GPL"                           [GNU Public License v2 or later]
*      "GPL v2"                        [GNU Public License v2]

-- 
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