[alsa-devel] Counting links in simple-card

[Daniel Baluta]

Thanks for your answer. See my comments inline

On Thu, Oct 10, 2019 at 2:37 AM Kuninori Morimoto
<kuninori.morimoto.gx at renesas.com> wrote:
>
>
> Hi Daniel
>
> > > Do you mean CPU-dummy + dummy-Codec ?
> > > But anyway, simple-card/audio-graph DPCM support is very limited.
> > > Unfortunately it doesn't have flexibility...
> >
> > Yes, exactly. I need 1 DAI link with 1 FE + 1 BE for DSP / SOF  usecase.
>
> simple-card support it
> if it needs convert-rate or convert-channels.

Yes, but this is needed for ASRC-like components. I don't think I can abuse
this usage for my usecase.

> Please check below
>
>         static simple_for_each_link(xxx)
>         {
>                 ...
>                 for_each_child_of_node(node, np) {
>                         /*
>                          * It is DPCM
>                          * if it has many CPUs,
>                          * or has convert-xxx property
>                          */
> (1)                     if (dpcm_selectable &&
> (2)                         (num > 2 ||
> (3)                          adata.convert_rate || adata.convert_channels))
>                                 ret = func_dpcm(priv, np, codec, li, is_top);
>                         ...
>
> (1) : using simple-scu-audio-card
> (2) : 2 nodes or more
> (3) : has convert-xxx property
>

In fact I just need 1 BE DAI link. My use case is with SOF where the
FE will be added by topology.

I think I can modify simple-card to do this. Just let me know if you
see something obviously wrong
on making the simple-card / simple-scu-card handling this case with
creating just 1 BE DAI link.

Maybe add a property like "dpcm".