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Message-ID: <d674ed95-1e90-8d81-1d1c-cc640808c81e@linaro.org>
Date:   Thu, 28 Jul 2022 18:42:37 +0200
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Subject: Re: [PATCH v2] ASoC: dt-bindings: fsl,sai: Convert format to
 json-schema
Content-Language: en-US
To:     Shengjiu Wang <shengjiu.wang@nxp.com>, lgirdwood@gmail.com,
        broonie@kernel.org, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, alsa-devel@alsa-project.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     shengjiu.wang@gmail.com
References: <1659020669-3946-1-git-send-email-shengjiu.wang@nxp.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <1659020669-3946-1-git-send-email-shengjiu.wang@nxp.com>
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On 28/07/2022 17:04, Shengjiu Wang wrote:
> Convert the NXP SAI binding to DT schema format using json-schema.
> 
> The Synchronous Audio Interface (SAI) provides an interface that
> supports full-duplex serial interfaces with frame synchronization
> formats such as I2S, AC97, TDM, and codec/DSP interfaces.
> 
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> ---
> changes in v2
> - fix exclusive property issue
> - fix order issue of compatible, clock-names, dma-names
> 

Thank you for your patch. There is something to discuss/improve.

>  .../devicetree/bindings/sound/fsl,sai.yaml    | 215 ++++++++++++++++++
>  .../devicetree/bindings/sound/fsl-sai.txt     |  95 --------
>  2 files changed, 215 insertions(+), 95 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/sound/fsl,sai.yaml
>  delete mode 100644 Documentation/devicetree/bindings/sound/fsl-sai.txt
> 
> diff --git a/Documentation/devicetree/bindings/sound/fsl,sai.yaml b/Documentation/devicetree/bindings/sound/fsl,sai.yaml
> new file mode 100644
> index 000000000000..3e3d99febd69
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/fsl,sai.yaml
> @@ -0,0 +1,215 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/sound/fsl,sai.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Freescale Synchronous Audio Interface (SAI).
> +
> +maintainers:
> +  - Shengjiu Wang <shengjiu.wang@nxp.com>
> +
> +description: |
> +  The SAI is based on I2S module that used communicating with audio codecs,
> +  which provides a synchronous audio interface that supports fullduplex
> +  serial interfaces with frame synchronization such as I2S, AC97, TDM, and
> +  codec/DSP interfaces.
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - const: fsl,vf610-sai
> +      - const: fsl,imx6sx-sai
> +      - const: fsl,imx6ul-sai
> +      - const: fsl,imx7ulp-sai
> +      - const: fsl,imx8mq-sai
> +      - const: fsl,imx8qm-sai
> +      - const: fsl,imx8ulp-sai

All these are an enum.

> +      - items:
> +          - enum:
> +              - fsl,imx8mm-sai
> +              - fsl,imx8mn-sai
> +              - fsl,imx8mp-sai
> +          - const: fsl,imx8mq-sai
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    items:
> +      - description: receive and transmit interrupt
> +
> +  dmas:
> +    maxItems: 2
> +
> +  dma-names:
> +    maxItems: 2
> +
> +  clocks:
> +    items:
> +      - description: The ipg clock for register access
> +      - description: master clock source 0 (obsoleted)
> +      - description: master clock source 1
> +      - description: master clock source 2
> +      - description: master clock source 3
> +      - description: PLL clock source for 8kHz series
> +      - description: PLL clock source for 11kHz series
> +    minItems: 4
> +
> +  clock-names:
> +    oneOf:
> +      - items:
> +          - const: bus
> +          - const: mclk0
> +          - const: mclk1
> +          - const: mclk2
> +          - const: mclk3
> +          - const: pll8k
> +          - const: pll11k
> +        minItems: 4
> +      - items:
> +          - const: bus
> +          - const: mclk1
> +          - const: mclk2
> +          - const: mclk3
> +          - const: pll8k
> +          - const: pll11k
> +        minItems: 4
> +
> +  lsb-first:
> +    $ref: /schemas/types.yaml#/definitions/flag

Be consistent, so:
type:boolean

> +    description: |
> +      Configures whether the LSB or the MSB is transmitted
> +      first for the fifo data. If this property is absent,
> +      the MSB is transmitted first as default, or the LSB
> +      is transmitted first.
> +
> +  big-endian:
> +    description: |
> +      required if all the SAI registers are big-endian rather than little-endian.
> +    type: boolean
> +
> +  fsl,sai-synchronous-rx:
> +    $ref: /schemas/types.yaml#/definitions/flag

type:boolean

> +    description: |
> +      SAI will work in the synchronous mode (sync Tx with Rx) which means
> +      both the transmitter and the receiver will send and receive data by
> +      following receiver's bit clocks and frame sync clocks.
> +
> +  fsl,sai-asynchronous:
> +    $ref: /schemas/types.yaml#/definitions/flag

type:boolean

> +    description: |
> +      SAI will work in the asynchronous mode, which means both transmitter
> +      and receiver will send and receive data by following their own bit clocks
> +      and frame sync clocks separately.
> +      If both fsl,sai-asynchronous and fsl,sai-synchronous-rx are absent, the
> +      default synchronous mode (sync Rx with Tx) will be used, which means both
> +      transmitter and receiver will send and receive data by following clocks
> +      of transmitter.
> +
> +  fsl,dataline:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    description: |
> +      Configure the dataline. It has 3 value for each configuration

and how many items in total?

> +    items:
> +      items:
> +        - description: format Default(0), I2S(1) or PDM(2)
> +          enum: [0, 1, 2]
> +        - description: dataline mask for 'rx'
> +        - description: dataline mask for 'tx'
> +
> +  fsl,sai-mclk-direction-output:
> +    $ref: /schemas/types.yaml#/definitions/flag

boolean

> +    description: |
> +      SAI will output the SAI MCLK clock.
> +
> +  fsl,shared-interrupt:
> +    $ref: /schemas/types.yaml#/definitions/flag

boolean
but the problem is it was not present in previous bindings and a change
in pure conversion was not mentioned/explained in commit msg.

> +    description: |
> +      Interrupt is shared with other modules.
> +
> +  "#sound-dai-cells":
> +    const: 0

Also a new property. If these are already used, please briefly explain
in commit msg the changes to binding from pure conversion.

> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: fsl,vf610-sai
> +    then:
> +      properties:
> +        dmas:
> +          items:
> +            - description: DMA controller phandle and request line for TX
> +            - description: DMA controller phandle and request line for RX
> +        dma-names:
> +          items:
> +            - const: tx
> +            - const: rx
> +    else:
> +      properties:
> +        dmas:
> +          items:
> +            - description: DMA controller phandle and request line for RX
> +            - description: DMA controller phandle and request line for TX
> +        dma-names:
> +          items:
> +            - const: rx
> +            - const: tx
> +  - if:
> +      required:
> +        - fsl,sai-asynchronous
> +    then:
> +      properties:
> +        fsl,sai-synchronous-rx: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - dmas
> +  - dma-names
> +  - clocks
> +  - clock-names

sound-dai-cells not required and not present in vf610-sai? That's a bit
unusual. Maybe it was missing?

> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/clock/vf610-clock.h>
> +    sai2: sai@40031000 {
> +        compatible = "fsl,vf610-sai";
> +        reg = <0x40031000 0x1000>;
> +        interrupts = <86 IRQ_TYPE_LEVEL_HIGH>;
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&pinctrl_sai2_1>;
> +        clocks = <&clks VF610_CLK_PLATFORM_BUS>,
> +                 <&clks VF610_CLK_SAI2>,
> +                 <&clks 0>, <&clks 0>;
> +        clock-names = "bus", "mclk1", "mclk2", "mclk3";
> +        dma-names = "tx", "rx";
> +        dmas = <&edma0 0 21>,
> +               <&edma0 0 20>;
> +        big-endian;
> +        lsb-first;
> +    };
> +
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/clock/imx8mm-clock.h>
> +    sai1: sai@30010000 {
> +        #sound-dai-cells = <0>;
> +        compatible = "fsl,imx8mm-sai", "fsl,imx8mq-sai";
> +        reg = <0x30010000 0x10000>;

First compatible, then reg, then the rest of properties.

> +        interrupts = <GIC_SPI 95 IRQ_TYPE_LEVEL_HIGH>;
> +        clocks = <&clk IMX8MM_CLK_SAI1_IPG>,
> +                 <&clk IMX8MM_CLK_DUMMY>,
> +                 <&clk IMX8MM_CLK_SAI1_ROOT>,
> +                 <&clk IMX8MM_CLK_DUMMY>, <&clk IMX8MM_CLK_DUMMY>;
> +        clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3";
> +        dmas = <&sdma2 0 2 0>, <&sdma2 1 2 0>;
> +        dma-names = "rx", "tx";
> +        fsl,dataline = <1 0xff 0xff 2 0xff 0x11>;
> +    };


Best regards,
Krzysztof