[PATCH 3/3] dt-bindings: dsp: fsl: Document newly introduced fsl, properties

[Daniel Baluta]

On Thu, Jul 15, 2021 at 5:59 PM Rob Herring <robh+dt at kernel.org> wrote:
>
> On Thu, Jul 15, 2021 at 8:18 AM Daniel Baluta <daniel.baluta at oss.nxp.com> wrote:
> >
> > From: Daniel Baluta <daniel.baluta at nxp.com>
> >
> > Document firmware-name, tplg-name and machine-drv-name properties.
>
> That's obvious from the diff.
>
> Why do you need these?
>
> >
> > Signed-off-by: Daniel Baluta <daniel.baluta at nxp.com>
> > ---
> >  .../devicetree/bindings/dsp/fsl,dsp.yaml      | 20 +++++++++++++++++++
> >  1 file changed, 20 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/dsp/fsl,dsp.yaml b/Documentation/devicetree/bindings/dsp/fsl,dsp.yaml
> > index 7afc9f2be13a..8095aa178e7c 100644
> > --- a/Documentation/devicetree/bindings/dsp/fsl,dsp.yaml
> > +++ b/Documentation/devicetree/bindings/dsp/fsl,dsp.yaml
> > @@ -60,6 +60,22 @@ properties:
> >        used by DSP (see bindings/reserved-memory/reserved-memory.txt)
> >      maxItems: 1
> >
> > +  firmware-name:
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    description:
> > +      If present, name of the file within the firmware search path containing
> > +      the DSP firmware loaded by SOF at DSP boot time.
> > +
> > +  tplg-name:
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    description:
> > +      Should contain the audio topology file name loaded by SOF driver.
>
> Is this some format the DSP requires? Why do we need a separate file?
> This is defined by the board or user config?

This is not specific to DSP but to ALSA (See ALSA topology [1]).

We need the .tplg file in order to describe the support Audio scenario
by our board.

This could be defined both by:

board:
- e.g our CPU board can have a baseboard attached (so the audio
scenario changes).
user config:
- e.g user wants to enable post processing or any audio component.

I couldnt find a good way to specify this except via DTS. Intel folks
derive this information from ACPI tables.

[1] https://www.alsa-project.org/wiki/ALSA_topology