Re: [PATCH 1/8] ASoC: rockchip: rk3308: add internal audio codec bindings

From: Krzysztof Kozlowski
Date: Thu Sep 08 2022 - 07:53:51 EST


On 07/09/2022 16:21, luca.ceresoli@xxxxxxxxxxx wrote:
> From: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
>
> Add device tree bindings document for the internal audio codec of the
> Rockchip RK3308 SoC.
>
> Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>

Use subject prefixes matching the subsystem (git log --oneline -- ...).

> ---
> .../bindings/sound/rockchip,rk3308-codec.yaml | 102 ++++++++++++++++++
> MAINTAINERS | 6 ++
> .../dt-bindings/sound/rockchip,rk3308-codec.h | 15 +++
> 3 files changed, 123 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/sound/rockchip,rk3308-codec.yaml
> create mode 100644 include/dt-bindings/sound/rockchip,rk3308-codec.h
>
> diff --git a/Documentation/devicetree/bindings/sound/rockchip,rk3308-codec.yaml b/Documentation/devicetree/bindings/sound/rockchip,rk3308-codec.yaml
> new file mode 100644
> index 000000000000..f3458f86ef06
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/rockchip,rk3308-codec.yaml
> @@ -0,0 +1,102 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/sound/rockchip,rk3308-codec.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Rockchip RK3308 Internal Codec
> +
> +description: |
> + This is the audio codec embedded in the Rockchip RK3308
> + SoC. It has 8 24-bit ADCs and 2 24-bit DACs. The maximum supported
> + sampling rate is 192 kHz.
> +
> + It is connected internally to one out of a selection of the internal I2S
> + controllers.
> +
> + The RK3308 audio codec has 8 independent capture channels, but some
> + features work on stereo pairs called groups:
> + * grp 0 -- MIC1 / MIC2
> + * grp 1 -- MIC3 / MIC4
> + * grp 2 -- MIC5 / MIC6
> + * grp 3 -- MIC7 / MIC8
> +
> +maintainers:
> + - Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
> +
> +properties:
> + compatible:
> + const: rockchip,rk3308-codec
> +
> + reg:
> + maxItems: 1
> +
> + rockchip,grf:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description:
> + Phandle to the General Register Files (GRF)
> +
> + clocks:
> + items:
> + - description: clock for TX
> + - description: clock for RX
> + - description: AHB clock driving the interface
> +
> + clock-names:
> + items:
> + - const: mclk_tx
> + - const: mclk_rx
> + - const: hclk
> +
> + resets: true

maxItems: 1

> +
> + reset-names:
> + items:
> + - const: "acodec"

No quotes.

> +
> + "#sound-dai-cells":
> + const: 0
> +
> + rockchip,micbias-avdd-multiplier:
> + description: |
> + Voltage setting for the MICBIAS pins expressed as a multiplier of
> + AVDD.
> +
> + E.g. if rockchip,micbias-avdd-multiplier = 7 (x0.85) and AVDD = 3v3,
> + then MIC BIAS voltage will be 3.3 V * 0.85 = 2.805 V.
> +
> + Value 0: multiplier = 0.50
> + Value N: multiplier = 0.50 + 0.05 * N
> + Value 7: multiplier = 0.85

Use logical values/units. The units is 0.05, so "-percent" in node name.
https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/property-units.yaml
Then drop ref and use enum.

> +
> + $ref: /schemas/types.yaml#/definitions/uint32
> + maximum: 7
> +
> +required:
> + - compatible
> + - reg
> + - rockchip,grf
> + - clocks
> + - resets
> + - "#sound-dai-cells"
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/clock/rk3308-cru.h>
> +
> + acodec: acodec@ff560000 {

codec

Node names should be generic.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> + compatible = "rockchip,rk3308-codec";
> + reg = <0xff560000 0x10000>;
> + rockchip,grf = <&grf>;
> + clock-names = "mclk_tx", "mclk_rx", "hclk";
> + clocks = <&cru SCLK_I2S2_8CH_TX_OUT>,
> + <&cru SCLK_I2S2_8CH_RX_OUT>,
> + <&cru PCLK_ACODEC>;
> + reset-names = "acodec";
> + resets = <&cru SRST_ACODEC_P>;
> + #sound-dai-cells = <0>;
> + };
> +
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 895e8ace80dd..d53a8e74cb1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -17588,6 +17588,12 @@ S: Maintained
> F: Documentation/devicetree/bindings/media/rockchip-rga.yaml
> F: drivers/media/platform/rockchip/rga/
>
> +ROCKCHIP RK3308 INTERNAL AUDIO CODEC
> +M: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
> +S: Maintained
> +F: Documentation/devicetree/bindings/sound/rockchip,rk3308-codec.yaml
> +F: include/dt-bindings/sound/rockchip,rk3308-codec.h
> +
> ROCKCHIP VIDEO DECODER DRIVER
> M: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx>
> L: linux-media@xxxxxxxxxxxxxxx
> diff --git a/include/dt-bindings/sound/rockchip,rk3308-codec.h b/include/dt-bindings/sound/rockchip,rk3308-codec.h
> new file mode 100644
> index 000000000000..9f1b210a048e
> --- /dev/null
> +++ b/include/dt-bindings/sound/rockchip,rk3308-codec.h
> @@ -0,0 +1,15 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */

Dual license.

> +#ifndef __DT_BINDINGS_ROCKCHIP_RK3308_CODEC_H__
> +#define __DT_BINDINGS_ROCKCHIP_RK3308_CODEC_H__
> +
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_50 0
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_55 1
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_60 2
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_65 3
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_70 4
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_75 5
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_80 6
> +#define RK3308_CODEC_MICBIAS_AVDD_x_0_85 7

You store register values in the bindings. Nope. Bindings are not for this.

Best regards,
Krzysztof