Re: [PATCHv4 9/9] ASoC: dt-bindings: fsl-asoc-card: add compatible for generic codec

Elinor Montmasson
2024-05-31T12:48:17Z

From: "Rob Herring" <robh@kernel.org>
Sent: Monday, 20 May, 2024 20:31:48
> On Wed, May 15, 2024 at 03:54:11PM +0200, Elinor Montmasson wrote:
>> Add documentation about new dts bindings following new support
>> for compatible "fsl,imx-audio-generic".
>>
>> Some CPU DAI don't require a real audio codec. The new compatible
>> "fsl,imx-audio-generic" allows using the driver with codec drivers
>> SPDIF DIT and SPDIF DIR as dummy codecs.
>> It also allows using not pre-configured audio codecs which
>> don't require specific control through a codec driver.
>>
>> The new dts properties give the possibility to set some parameters
>> about the CPU DAI usually set through the codec configuration.
>>
>> Signed-off-by: Elinor Montmasson <elinor.montmasson@savoirfairelinux.com>
>> ---
>> .../bindings/sound/fsl-asoc-card.yaml | 96 ++++++++++++++++++-
>> 1 file changed, 92 insertions(+), 4 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/sound/fsl-asoc-card.yaml
>> b/Documentation/devicetree/bindings/sound/fsl-asoc-card.yaml
>> index 9922664d5ccc..332d8bf96e06 100644
>> --- a/Documentation/devicetree/bindings/sound/fsl-asoc-card.yaml
>> +++ b/Documentation/devicetree/bindings/sound/fsl-asoc-card.yaml
>> @@ -23,6 +23,16 @@ description:
>> and PCM DAI formats. However, it'll be also possible to support those non
>> AC'97/I2S/PCM type sound cards, such as S/PDIF audio and HDMI audio, as
>> long as the driver has been properly upgraded.
>> + To use CPU DAIs that do not require a codec such as an S/PDIF controller,
>> + or to use a DAI to output or capture raw I2S/TDM data, you can
>> + use the compatible "fsl,imx-audio-generic".
>> +
>> +definitions:
>> + imx-audio-generic-dependency:
>> + properties:
>> + compatible:
>> + contains:
>> + const: fsl,imx-audio-generic
>>
>> maintainers:
>> - Shengjiu Wang <shengjiu.wang@nxp.com>
>> @@ -81,6 +91,7 @@ properties:
>> - fsl,imx-audio-wm8960
>> - fsl,imx-audio-wm8962
>> - fsl,imx-audio-wm8958
>> + - fsl,imx-audio-generic
>>
>> model:
>> $ref: /schemas/types.yaml#/definitions/string
>> @@ -93,8 +104,14 @@ properties:
>> need to add ASRC support via DPCM.
>>
>> audio-codec:
>> - $ref: /schemas/types.yaml#/definitions/phandle
>> - description: The phandle of an audio codec
>> + $ref: /schemas/types.yaml#/definitions/phandle-array
>> + description: |
>> + The phandle of an audio codec.
>> + If using the "fsl,imx-audio-generic" compatible, give instead a pair of
>> + phandles with the spdif_transmitter first (driver SPDIF DIT) and the
>> + spdif_receiver second (driver SPDIF DIR).
>
> minItems: 1
> maxItems: 2
>
>> + items:
>> + maxItems: 1
>>
>> audio-cpu:
>> $ref: /schemas/types.yaml#/definitions/phandle
>> @@ -150,8 +167,8 @@ properties:
>> description: dai-link uses bit clock inversion.
>>
>> mclk-id:
>> - $ref: /schemas/types.yaml#/definitions/uint32
>> - description: main clock id, specific for each card configuration.
>> + $ref: /schemas/types.yaml#/definitions/uint32-array
>> + description: Main clock id for each codec, specific for each card
>> configuration.
>
> minItems: 1
> maxItems: 2
>>
>> mux-int-port:
>> $ref: /schemas/types.yaml#/definitions/uint32
>> @@ -167,10 +184,68 @@ properties:
>> $ref: /schemas/types.yaml#/definitions/phandle
>> description: The phandle of an CPU DAI controller
>>
>> + # Properties relevant only with "fsl,imx-audio-generic" compatible
>> + dai-tdm-slot-width:
>> + description: See tdm-slot.txt.
>> + $ref: /schemas/types.yaml#/definitions/uint32
>> +
>> + dai-tdm-slot-num:
>> + description: See tdm-slot.txt.
>> + $ref: /schemas/types.yaml#/definitions/uint32
>> +
>> + clocks:
>> + description: |
>> + The CPU DAI system clock, used to retrieve
>> + the CPU DAI system clock frequency with the generic codec.
>> + maxItems: 1
>> +
>> + clock-names:
>> + items:
>> + - const: cpu_sysclk
>> +
>> + cpu-system-clock-direction-out:
>> + description: |
>> + Specifies cpu system clock direction as 'out' on initialization.
>> + If not set, direction is 'in'.
>> + $ref: /schemas/types.yaml#/definitions/flag
>> +
>> +dependencies:
>> + dai-tdm-slot-width:
>> + $ref: "#/definitions/imx-audio-generic-dependency"
>> + dai-tdm-slot-num:
>> + $ref: "#/definitions/imx-audio-generic-dependency"
>> + clocks:
>> + $ref: "#/definitions/imx-audio-generic-dependency"
>> + cpu-system-clock-direction-out:
>> + $ref: "#/definitions/imx-audio-generic-dependency"
>
> This works, but is an unusual pattern...
>
>> +
>> required:
>> - compatible
>> - model
>>
>> +allOf:
>> + - if:
>> + $ref: "#/definitions/imx-audio-generic-dependency"
>> + then:
>> + properties:
>> + audio-codec:
>> + items:
>> + - description: SPDIF DIT phandle
>> + - description: SPDIF DIR phandle
>> + mclk-id:
>> + maxItems: 1
>> + items:
>> + minItems: 1
>> + maxItems: 2
>> + else:
>> + properties:
>> + audio-codec:
>> + maxItems: 1
>> + mclk-id:
>> + maxItems: 1
>> + items:
>> + maxItems: 1
>
>
> You can handle the dependency like this instead:
>
> dai-tdm-slot-width: false
> dai-tdm-slot-num: false
>
>
> And then you don't need the definitions.
>
>> +
>> unevaluatedProperties: false
>>
>> examples:
>> @@ -195,3 +270,16 @@ examples:
>> "AIN2L", "Line In Jack",
>> "AIN2R", "Line In Jack";
>> };
>> +
>> + - |
>> + #include <dt-bindings/clock/imx8mn-clock.h>
>> + sound-spdif-asrc {
>> + compatible = "fsl,imx-audio-generic";
>> + model = "spdif-asrc-audio";
>> + audio-cpu = <&spdif>;
>> + audio-asrc = <&easrc>;
>> + audio-codec = <&spdifdit>, <&spdifdir>;
>> + clocks = <&clk IMX8MN_CLK_SAI5_ROOT>;
>> + clock-names = "cpu_sysclk";
>> + cpu-system-clock-direction-out;
>> + };
>> --
>> 2.34.1

Ok, thank you for the review, I'll make these modifications in v5.