Re: [PATCH 04/10] dt-bindings: mmc: Add RDA SDMMC controller

[Rob Herring <robh@kernel.org>]

On Fri, Sep 19, 2025 at 01:48:44AM +0700, Dang Huynh wrote:
> Add documentation describing the SD/MMC controller in RDA Micro
> RDA8810PL SoC.
> 
> Signed-off-by: Dang Huynh <dang.huynh@mainlining.org>
> ---
>  Documentation/devicetree/bindings/mmc/rda,mmc.yaml | 92 ++++++++++++++++++++++
>  1 file changed, 92 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/rda,mmc.yaml b/Documentation/devicetree/bindings/mmc/rda,mmc.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..f3cda38abd66023ca9bc94d1c29df5ae9e211e7c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/rda,mmc.yaml
> @@ -0,0 +1,92 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mmc/rda,mmc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: RDA Micro SD/MMC Controller
> +
> +allOf:
> +  - $ref: mmc-controller.yaml
> +
> +maintainers:
> +  - Dang Huynh <dang.huynh@mainlining.org>
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - rda,8810pl-mmc
> +      - const: rda,mmc

Drop the generic compatible.

> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    const: mclk
> +
> +  resets:
> +    maxItems: 1
> +
> +  dmas:
> +    maxItems: 2
> +
> +  dma-names:
> +    items:
> +      - const: tx
> +      - const: rx
> +
> +  rda,mclk-adj:
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    description:
> +      Some board need MCLK output to be delayed for the card to work.
> +      If not present, MCLK output is not delayed.
> +    minimum: 0
> +    maximum: 255

You can drop the constraints if they are not less than uint8 range.

What are the units? 

I guess 'adj' means adjust. Just use 'rda,mclk-delay' to be more 
precise.

> +
> +  rda,mclk-inv:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      Some board need MCLK to be inverted for the card to work.
> +      If not present, MCLK is not inverted.
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +  - resets
> +  - dmas
> +  - dma-names
> +  - vmmc-supply
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/clock/rda,8810pl-apclk.h>
> +    #include <dt-bindings/dma/rda-ifc.h>
> +    mmc@20950000 {
> +      compatible = "rda,8810pl-mmc", "rda,mmc";
> +      reg = <0x20950000 0x1000>;
> +      interrupts = <3 IRQ_TYPE_LEVEL_HIGH>;
> +      clocks = <&ap_syscon CLK_APB2>;
> +      clock-names = "mclk";
> +      resets = <&ap_syscon RST_APB2_SDMMC1>;
> +      dmas = <&ifc IFC_SDMMC1_TX>, <&ifc IFC_SDMMC1_RX>;
> +      dma-names = "tx", "rx";
> +      vmmc-supply = <&vdd_sdmmc>;
> +      rda,mclk-adj = /bits/ 8 <1>;
> +      rda,mclk-inv;
> +    };
> +
> +...
> 
> -- 
> 2.51.0
>