Re: [RFC PATCH 1/2] dt-bindings: media: snps,dw-hdmi-rx: add #sound-dai-cells

[Royal Net]

> Should the constraint be set to 0 to follow standard device tree
> norms?

Fair point. The current RFC wires up a single I2S DAI, and for a
single-DAI provider 0 is indeed the norm -- rockchip,dw-hdmi does
exactly that for its one DAI on the TX side.

The reason I picked 1 is that the controller also has an S/PDIF
audio output path (the vendor driver exposes both I2S and S/PDIF
DAIs through hdmi-codec), so a DAI index becomes meaningful if that
second path is wired up later.

Unless the DT maintainers prefer keeping 1 from the start to avoid
changing the cell count if/when the S/PDIF DAI is added, I'll switch
to const: 0 in the next revision -- please let me know which you'd
prefer.

Igor

On Wed, Jul 15, 2026 at 7:54 AM <sashiko-bot@xxxxxxxxxx> wrote:
>
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] Incorrect cell count constraint for single-DAI provider.
> --
>
> --- Patch [1]: [RFC PATCH 1/2] dt-bindings: media: snps,dw-hdmi-rx: add #sound-dai-cells ---
> commit e6b0bac0b97f568ce749084e6c1e728bcd258b10
> Author: Igor Paunovic <royalnet026@xxxxxxxxx>
> dt-bindings: media: snps,dw-hdmi-rx: add #sound-dai-cells
>
> This commit adds the #sound-dai-cells property to the HDMI RX controller
> bindings, enabling a generic audio codec to capture incoming embedded audio.
>
> > diff --git a/Documentation/devicetree/bindings/media/snps,dw-hdmi-rx.yaml b/Documentation/devicetree/bindings/media/snps,dw-hdmi-rx.yaml
> > index b7f6c87d0e06a..83c10d9997c8e 100644
> > --- a/Documentation/devicetree/bindings/media/snps,dw-hdmi-rx.yaml
> > +++ b/Documentation/devicetree/bindings/media/snps,dw-hdmi-rx.yaml
> > @@ -78,6 +78,13 @@ properties:
> >        The phandle of the syscon node for the Video Output GRF register
> >        to enable EDID transfer through SDAIN and SCLIN.
> >
> > +  "#sound-dai-cells":
> > +    const: 1
> > +    description:
> > +      The HDMI RX controller registers a generic HDMI audio codec so the
> > +      audio embedded in the incoming stream can be captured. A value of 1
> > +      lets a sound card reference the audio DAI as <&hdmirx 0>.
>
> [Severity: Medium]
> Is this cell count constraint correct for a single-DAI provider?
>
> Looking at properties:#sound-dai-cells, the hardware exposes only a single
> generic audio DAI. Requiring a cell count of 1 forces device tree nodes to
> use a non-standard syntax like <&hdmirx 0> instead of just <&hdmirx> for a
> single resource.
>
> Should the constraint be set to 0 to follow standard device tree norms?
>
> --
> Sashiko AI review · https://sashiko.dev/#/patchset/20260715051939.64652-1-royalnet026@xxxxxxxxx?part=1