[alsa-devel] [PATCH 2/4] soc-dai: add bitfields for hardware I2S formats

[Mark Brown]

On Thu, Mar 05, 2009 at 12:12:23AM +0100, Daniel Mack wrote:
> On Wed, Mar 04, 2009 at 10:30:58PM +0000, Mark Brown wrote:

> > devices on the link.  Have you considered handling this through that,
> > perhaps through adding a virtual thing to configure (eg, a
> > PXA_SSP_FRAME_CLOCKS)?

> I thought about that but then I condidered it's actually the wrong place
> for such a setting. I see two statements the board file has to make:

The other option would be to use the TDM mode interface to set this up
since that's roughly what it is; my main concern here is that we already
have two ways of doing this and I'd like to try to keep the number down
for consistency.

> It could be possible to express that in clk division rations, but it is
> actually a lot more straight forward to make that setting once rather
> then changing it over and over again.

I think it's all much of a muchness in terms of complexity whatever
option is chosen.

> > I guess cs4270.c ought to be enforcing this if it's added...

> cs4270.c would need that flag to be set or fail otherwise. Don't know if
> that really makes life easier for board support files that are not
> mainline. Want me to do that?

If this gets merged it's probably for the best (at least when it's in
slave mode).  Or add a hint to that effect.

> > FF_I2S should probably be something else since something might need this
> > for non-I2S devices - _BIT, perhaps?

> For non-I2S devices, we could re-use the same bit space as they will
> never appear in the same format word anyway, right?

Yes, I'm just thinking we should be able to use the same name for this
with every format.