Re: [PATCH v2 3/9] ASoC: audio-graph: Identify 'no_pcm' DAI links for DPCM

[Sameer Pujar]

Hi Kuninori,

On 8/18/2020 8:11 AM, Kuninori Morimoto wrote:
> External email: Use caution opening links or attachments
>
>
> Hi Sameer
>
> > PCM devices are created for FE dai links with 'no-pcm' flag as '0'.
> > Such DAI links have CPU component which implement either pcm_construct()
> > or pcm_new() at component or dai level respectively. Based on this,
> > current patch exposes a helper function to identify such components
> > and populate 'no_pcm' flag for DPCM DAI link.
> >
> > This helps to have BE<->BE component links where PCM devices need
> > not be created for CPU component involved in such links.
> >
> > Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx>
> > ---
> (snip)
> > @@ -259,6 +270,16 @@ static int graph_dai_link_of_dpcm(struct asoc_simple_priv *priv,
> >                if (ret < 0)
> >                        goto out_put_node;
> >
> > +             /*
> > +              * In BE<->BE connections it is not required to create
> > +              * PCM devices at CPU end of the dai link and thus 'no_pcm'
> > +              * flag needs to be set. It is useful when there are many
> > +              * BE components and some of these have to be connected to
> > +              * form a valid audio path.
> > +              */
> > +             if (!soc_component_is_pcm(cpus))
> > +                     dai_link->no_pcm = 1;
> > +
> For safety, I want to judge with data->component_chaining.
>
>          if (data->component_chaining &&
>              !soc_component_is_pcm(cpus))
>                          dai_link->no_pcm = 1;

OK. I will keep the additional check. Thanks.

> Thank you for your help !!
>
> Best regards
> ---
> Kuninori Morimoto