Subject: Re: [PATCH v2 7/7] ASoC: dt-bindings: imx-rpmsg: Add binding doc for rpmsg machine driver

From: Rob Herring <[email-masked]>
Date: Wed, 10 Feb 2021 16:17:04 -0600

On Sun, Feb 07, 2021 at 06:23:55PM +0800, Shengjiu Wang wrote:
> Imx-rpmsg is a new added machine driver for supporting audio on Cortex-M
> core. The Cortex-M core will control the audio interface, DMA and audio
> codec, setup the pipeline, the audio driver on Cortex-A core side is just
> to communitcate with M core, it is a virtual sound card and don't touch
> the hardware.

I don't understand why there are 2 nodes for this other than you happen 
to want to split this into 2 Linux drivers. It's 1 h/w thing. 

> 
> Signed-off-by: Shengjiu Wang <[email-masked]>
> ---
>  .../bindings/sound/imx-audio-rpmsg.yaml       | 48 +++++++++++++++++++
>  1 file changed, 48 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/sound/imx-audio-rpmsg.yaml
> 
> diff --git a/Documentation/devicetree/bindings/sound/imx-audio-rpmsg.yaml b/Documentation/devicetree/bindings/sound/imx-audio-rpmsg.yaml
> new file mode 100644
> index 000000000000..b941aeb80678
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/imx-audio-rpmsg.yaml
> @@ -0,0 +1,48 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/sound/imx-audio-rpmsg.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NXP i.MX audio complex with rpmsg
> +
> +maintainers:
> +  - Shengjiu Wang <[email-masked]>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - fsl,imx-audio-rpmsg
> +
> +  model:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description: User specified audio sound card name
> +
> +  audio-cpu:
> +    description: The phandle of an CPU DAI controller
> +
> +  rpmsg-out:
> +    description: |
> +      This is a boolean property. If present, the transmitting function
> +      will be enabled,
> +
> +  rpmsg-in:
> +    description: |
> +      This is a boolean property. If present, the receiving function
> +      will be enabled.
> +
> +required:
> +  - compatible
> +  - model
> +  - audio-cpu
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    sound-rpmsg {
> +        compatible = "fsl,imx-audio-rpmsg";
> +        model = "ak4497-audio";
> +        audio-cpu = <&rpmsg_audio>;
> +        rpmsg-out;
> +    };
> -- 
> 2.27.0
>