Re: [PATCH v2 3/7] ASoC: dt-bindings: fsl_rpmsg: Add binding doc for rpmsg cpu dai driver

From: Rob Herring
Date: Wed Feb 10 2021 - 17:13:57 EST


On Sun, Feb 07, 2021 at 06:23:51PM +0800, Shengjiu Wang wrote:
> fsl_rpmsg cpu dai driver is driver for rpmsg audio, which is mainly used
> for getting the user's configuration from device tree and configure the
> clocks which is used by Cortex-M core. So in this document define the
> needed property.
>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> ---
> .../devicetree/bindings/sound/fsl,rpmsg.yaml | 80 +++++++++++++++++++
> 1 file changed, 80 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml
>
> diff --git a/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml
> new file mode 100644
> index 000000000000..2d3ce10d42fc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml
> @@ -0,0 +1,80 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/sound/fsl,rpmsg.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NXP Audio RPMSG CPU DAI Controller
> +
> +maintainers:
> + - Shengjiu Wang <shengjiu.wang@xxxxxxx>
> +
> +properties:
> + compatible:
> + enum:
> + - fsl,imx7ulp-rpmsg
> + - fsl,imx8mn-rpmsg
> + - fsl,imx8mm-rpmsg
> + - fsl,imx8mp-rpmsg

rpmsg is a protocol. What's the h/w block?

> +
> + clocks:
> + items:
> + - description: Peripheral clock for register access
> + - description: Master clock
> + - description: DMA clock for DMA register access
> + - description: Parent clock for multiple of 8kHz sample rates
> + - description: Parent clock for multiple of 11kHz sample rates
> + minItems: 5
> +
> + clock-names:
> + items:
> + - const: ipg
> + - const: mclk
> + - const: dma
> + - const: pll8k
> + - const: pll11k
> + minItems: 5
> +
> + power-domains:
> + maxItems: 1
> +
> + fsl,audioindex:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: instance index for rpmsg image
> +
> + fsl,version:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: rpmsg image version index

What are these 2 used for?

> +
> + fsl,buffer-size:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: pre allocate dma buffer size
> +
> + fsl,enable-lpa:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description: enable low power audio path.
> +
> + fsl,codec-type:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: Sometimes the codec is registered by
> + driver not the device tree, this items
> + can be used to distinguish codecs

0-2^32 are valid values?

> +
> +required:
> + - compatible
> + - fsl,audioindex
> + - fsl,version
> + - fsl,buffer-size
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + rpmsg_audio: rpmsg_audio {
> + compatible = "fsl,imx8mn-rpmsg";
> + fsl,audioindex = <0> ;
> + fsl,version = <2>;
> + fsl,buffer-size = <0x6000000>;
> + fsl,enable-lpa;
> + status = "okay";

Don't show status in examples.

> + };
> --
> 2.27.0
>