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

Elinor Montmasson
2024-05-15T13:54:40Z

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).
+ 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.

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"
+
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
+
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