Re: [PATCH v3 17/20] ASoC: dt-bindings: tas2770: add flags for SDOUT pulldown and zero-fill

[Rob Herring]

On Fri, Mar 07, 2025 at 04:18:31PM +1000, James Calligeros wrote:
> On Wed, Mar 5, 2025 at 11:22 PM Rob Herring <robh@xxxxxxxxxx> wrote:
> > This just feels like something common because any TDM interface may need
> > to control this. It's not really a property of the chip, but requirement
> > of the TDM interface.
> 
> What I'm imagining then is something like:
> 
> dai-link@0 {
>     cpu {
>         sound-dai = <&some_cpu>;
>     };
>     codec {
>         sound-dai = <&some_codec>;
>         dai-tdm-tx-zerofill;
>         dai-tdm-tx-pulldown; /* either or, having both makes no sense */

If they are mutually exclusive, it's best to design the properties that 
way. So something like:

dai-tdm-tx-idle = "zerofill";
dai-tdm-tx-idle = "pulldown";

>     };
> };
> 
> Codec drivers would then provide a function to set TDM TX behaviour if they
> support it, and export that as a dai op for use by machine drivers
> when they parse
> the dai link similar to dai-tdm-tx-slot and friends. Is that close to
> what you have
> in mind?

How would it work when you need a mask? "dai-tdm-slot-tx-mask" is 
enough?

Rob