Re: [PATCH 2/5] dt-bindings: mfd: atmel,at91-usart: convert to json-schema

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 17/08/2022 10:55, Sergiu Moga wrote:
> Convert at91 USART DT Binding for Atmel/Microchip SoCs to
> json-schema format.
> 
> Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
> ---
>  .../bindings/mfd/atmel,at91-usart.yaml        | 190 ++++++++++++++++++
>  .../devicetree/bindings/mfd/atmel-usart.txt   |  98 ---------
>  2 files changed, 190 insertions(+), 98 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mfd/atmel,at91-usart.yaml
>  delete mode 100644 Documentation/devicetree/bindings/mfd/atmel-usart.txt
> 
> diff --git a/Documentation/devicetree/bindings/mfd/atmel,at91-usart.yaml b/Documentation/devicetree/bindings/mfd/atmel,at91-usart.yaml
> new file mode 100644
> index 000000000000..cf15d73fa1e8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/atmel,at91-usart.yaml
> @@ -0,0 +1,190 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2022 Microchip Technology, Inc. and its subsidiaries
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/atmel,at91-usart.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Atmel Universal Synchronous Asynchronous Receiver/Transmitter (USART)
> +
> +maintainers:
> +  - Richard Genoud <richard.genoud@gmail.com>
> +
> +properties:
> +  compatible:
> +    oneOf:

This looks quite different than bindings and you commit msg is saying it
is only a conversion. Mention any changes against original bindings.

> +      - const: atmel,at91rm9200-usart
> +      - const: atmel,at91sam9260-usart
> +      - const: microchip,sam9x60-usart

That's an enum

> +      - items:
> +          - const: atmel,at91rm9200-dbgu
> +          - const: atmel,at91rm9200-usart
> +      - items:
> +          - const: atmel,at91sam9260-dbgu
> +          - const: atmel,at91sam9260-usart
> +      - items:
> +          - const: microchip,sam9x60-dbgu
> +          - const: microchip,sam9x60-usart
> +      - items:
> +          - const: microchip,sam9x60-usart
> +          - const: atmel,at91sam9260-usart

This is not correct - contradicts earlier one.

> +      - items:
> +          - const: microchip,sam9x60-dbgu
> +          - const: microchip,sam9x60-usart
> +          - const: atmel,at91sam9260-dbgu
> +          - const: atmel,at91sam9260-usart

What? You wrote above that microchip,sam9x60-dbgu is compatible only
with microchip,sam9x60-usart. Now you write it is also compatible with
other ones?

> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clock-names:
> +    contains:
> +      const: usart

No, this has to be specific/fixed list.

> +
> +  clocks:
> +    minItems: 1
> +    maxItems: 2

Not really - define the items. One item could be optional, though.

> +
> +  dmas:
> +    items:
> +      - description: TX DMA Channel
> +      - description: RX DMA Channel
> +
> +  dma-names:
> +    items:
> +      - const: tx
> +      - const: rx
> +
> +  atmel,usart-mode:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: |

No need for |

> +      Must be either 1 for SPI or 0 for USART.

Mention the header.

> +    enum: [ 0, 1 ]
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clock-names
> +  - clocks
> +
> +if:

Put it under allOf.

> +  properties:
> +    $nodename:
> +      pattern: "^serial@[0-9a-f]+$"
> +then:
> +  allOf:
> +    - $ref: /schemas/serial/serial.yaml#
> +    - $ref: /schemas/serial/rs485.yaml#
> +
> +  properties:
> +    atmel,use-dma-rx:
> +      type: boolean
> +      description: use of PDC or DMA for receiving data
> +
> +    atmel,use-dma-tx:
> +      type: boolean
> +      description: use of PDC or DMA for transmitting data
> +
> +    atmel,fifo-size:
> +      $ref: /schemas/types.yaml#/definitions/uint32
> +      description: |

No need for |

> +        Maximum number of data the RX and TX FIFOs can store for FIFO
> +        capable USARTS.
> +      enum: [ 16, 32 ]
> +
> +else:
> +  if:
> +    properties:
> +      $nodename:
> +        pattern: "^spi@[0-9a-f]+$"
> +  then:
> +    allOf:
> +      - $ref: /schemas/spi/spi-controller.yaml#
> +
> +    properties:
> +      atmel,usart-mode:
> +        const: 1
> +
> +      "#size-cells":
> +        const: 0
> +
> +      "#address-cells":
> +        const: 1
> +
> +    required:
> +      - atmel,usart-mode
> +      - "#size-cells"
> +      - "#address-cells"
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/mfd/at91-usart.h>
> +    #include <dt-bindings/dma/at91.h>
> +
> +    /* use PDC */
> +    usart0: serial@fff8c000 {
> +        compatible = "atmel,at91sam9260-usart";
> +        reg = <0xfff8c000 0x4000>;
> +        interrupts = <7>;
> +        clocks = <&usart0_clk>;
> +        clock-names = "usart";
> +        atmel,use-dma-rx;
> +        atmel,use-dma-tx;
> +        rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
> +        cts-gpios = <&pioD 16 GPIO_ACTIVE_LOW>;
> +        dtr-gpios = <&pioD 17 GPIO_ACTIVE_LOW>;
> +        dsr-gpios = <&pioD 18 GPIO_ACTIVE_LOW>;
> +        dcd-gpios = <&pioD 20 GPIO_ACTIVE_LOW>;
> +        rng-gpios = <&pioD 19 GPIO_ACTIVE_LOW>;
> +    };
> +
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/mfd/at91-usart.h>
> +    #include <dt-bindings/dma/at91.h>
> +
> +    /* use DMA */
> +    usart1: serial@f001c000 {
> +        compatible = "atmel,at91sam9260-usart";
> +        reg = <0xf001c000 0x100>;
> +        interrupts = <12 IRQ_TYPE_LEVEL_HIGH 5>;
> +        clocks = <&usart0_clk>;
> +        clock-names = "usart";
> +        atmel,use-dma-rx;
> +        atmel,use-dma-tx;
> +        dmas = <&dma0 2 AT91_DMA_CFG_PER_ID(3)>,
> +               <&dma0 2 (AT91_DMA_CFG_PER_ID(4) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +        dma-names = "tx", "rx";
> +        atmel,fifo-size = <32>;
> +    };
> +
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/mfd/at91-usart.h>
> +    #include <dt-bindings/dma/at91.h>
> +
> +    /* SPI mode */
> +    spi0: spi@f001c000 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        compatible = "atmel,at91sam9260-usart";
> +        atmel,usart-mode = <AT91_USART_MODE_SPI>;
> +        reg = <0xf001c000 0x100>;

compatible, then reg then the reset of properties

> +        interrupts = <12 IRQ_TYPE_LEVEL_HIGH 5>;
> +        clocks = <&usart0_clk>;
> +        clock-names = "usart";
> +        dmas = <&dma0 2 AT91_DMA_CFG_PER_ID(3)>,
> +               <&dma0 2 (AT91_DMA_CFG_PER_ID(4) | AT91_DMA_CFG_FIFOCFG_ASAP)>;
> +        dma-names = "tx", "rx";
> +        cs-gpios = <&pioB 3 GPIO_ACTIVE_HIGH>;
> +    };

Best regards,
Krzysztof