Re: [alsa-devel] [PATCH] ASoC: fsl_sai: Implement set_bclk_ratio

[Nicolin Chen]

On Wed, Sep 11, 2019 at 04:06:41PM +0300, Daniel Baluta wrote:
> On Wed, Sep 11, 2019 at 2:01 PM Mark Brown <broonie@xxxxxxxxxx> wrote:
> >
> > On Thu, Sep 05, 2019 at 06:29:39PM -0700, Nicolin Chen wrote:
> > > On Sat, Aug 31, 2019 at 12:59:10AM +0300, Daniel Baluta wrote:
> >
> > > > This is to allow machine drivers to set a certain bitclk rate
> > > > which might not be exactly rate * frame size.
> >
> > > Just a quick thought of mine: slot_width and slots could be
> > > set via set_dai_tdm_slot() actually, while set_bclk_ratio()
> > > would override that one with your change. I'm not sure which
> > > one could be more important...so would you mind elaborating
> > > your use case?
> >
> > The reason we have both operations is partly that some hardware
> > can configure the ratio but not do TDM and partly that setting
> > TDM slots forces us to configure the slot size depending on the
> > current stream configuration while just setting the ratio means
> > we can just fix the configuration once.  I'd say it's just a user
> > error to try to do both simultaneously.
> 
> Yes, exactly. We wanted to have a better control of bclk freq.
> Sorry for the late answer, I'm traveling.

I see. Thanks for the explain. Just acked.