Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml

# 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@nxp.com>

description: |
  fsl_rpmsg is a virtual audio device. Mapping to real hardware devices
  are SAI, MICFIL, DMA controlled by Cortex M core. What we see from
  Linux side is a device which provides audio service by rpmsg channel.
  We can create different sound cards which access different hardwares
  such as SAI, MICFIL, .etc through building rpmsg channels between
  Cortex-A and Cortex-M.

properties:
  compatible:
    enum:
      - fsl,imx7ulp-rpmsg-audio
      - fsl,imx8mn-rpmsg-audio
      - fsl,imx8mm-rpmsg-audio
      - fsl,imx8mp-rpmsg-audio
      - fsl,imx8ulp-rpmsg-audio

  model:
    $ref: /schemas/types.yaml#/definitions/string
    description: User specified audio sound card name

  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

  clock-names:
    items:
      - const: ipg
      - const: mclk
      - const: dma
      - const: pll8k
      - const: pll11k

  power-domains:
    description:
      List of phandle and PM domain specifier as documented in
      Documentation/devicetree/bindings/power/power_domain.txt
    maxItems: 1

  memory-region:
    maxItems: 1
    description:
      phandle to a node describing reserved memory (System RAM memory)
      The M core can't access all the DDR memory space on some platform,
      So reserved a specific memory for dma buffer which M core can
      access.
      (see bindings/reserved-memory/reserved-memory.txt)

  audio-codec:
    $ref: /schemas/types.yaml#/definitions/phandle
    description: The phandle to a node of audio codec

  audio-routing:
    $ref: /schemas/types.yaml#/definitions/non-unique-string-array
    description: |
      A list of the connections between audio components. Each entry is a
      pair of strings, the first being the connection's sink, the second
      being the connection's source.

  fsl,enable-lpa:
    $ref: /schemas/types.yaml#/definitions/flag
    description: enable low power audio path.

  fsl,rpmsg-out:
    $ref: /schemas/types.yaml#/definitions/flag
    description: |
      This is a boolean property. If present, the transmitting function
      will be enabled.

  fsl,rpmsg-in:
    $ref: /schemas/types.yaml#/definitions/flag
    description: |
      This is a boolean property. If present, the receiving function
      will be enabled.

  fsl,rpmsg-channel-name:
    $ref: /schemas/types.yaml#/definitions/string
    description: |
      A string property to assign rpmsg channel this sound card sits on.
      This property can be omitted if there is only one sound card and it sits
      on "rpmsg-audio-channel".
    enum:
      - rpmsg-audio-channel
      - rpmsg-micfil-channel

required:
  - compatible
  - model

additionalProperties: false

examples:
  - |
    #include <dt-bindings/clock/imx8mn-clock.h>

    rpmsg_audio: rpmsg_audio {
        compatible = "fsl,imx8mn-rpmsg-audio";
        model = "wm8524-audio";
        fsl,enable-lpa;
        fsl,rpmsg-out;
        clocks = <&clk IMX8MN_CLK_SAI3_IPG>,
                 <&clk IMX8MN_CLK_SAI3_ROOT>,
                 <&clk IMX8MN_CLK_SDMA3_ROOT>,
                 <&clk IMX8MN_AUDIO_PLL1_OUT>,
                 <&clk IMX8MN_AUDIO_PLL2_OUT>;
        clock-names = "ipg", "mclk", "dma", "pll8k", "pll11k";
    };

  - |
    #include <dt-bindings/clock/imx8mm-clock.h>

    rpmsg_micfil: audio-controller {
        compatible = "fsl,imx8mm-rpmsg-audio";
        model = "micfil-audio";
        fsl,rpmsg-channel-name = "rpmsg-micfil-channel";
        fsl,enable-lpa;
        fsl,rpmsg-in;
        clocks = <&clk IMX8MM_CLK_PDM_IPG>,
                 <&clk IMX8MM_CLK_PDM_ROOT>,
                 <&clk IMX8MM_CLK_SDMA3_ROOT>,
                 <&clk IMX8MM_AUDIO_PLL1_OUT>,
                 <&clk IMX8MM_AUDIO_PLL2_OUT>;
        clock-names = "ipg", "mclk", "dma", "pll8k", "pll11k";
    };

...