Re: [PATCH 1/4] dt-bindings: mfd: atmel,flexcom: Convert to json-schema

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

On 03/05/2022 12:55, Kavyasree Kotagiri wrote:
> Convert the Atmel flexcom device tree bindings to json schema.
> 
> Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
> ---
>  .../bindings/mfd/atmel,flexcom.yaml           | 68 +++++++++++++++++++
>  .../devicetree/bindings/mfd/atmel-flexcom.txt | 63 -----------------
>  2 files changed, 68 insertions(+), 63 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
>  delete mode 100644 Documentation/devicetree/bindings/mfd/atmel-flexcom.txt
> 

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

> diff --git a/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml b/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
> new file mode 100644
> index 000000000000..62dea9b891d8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
> @@ -0,0 +1,68 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/atmel,flexcom.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Device tree bindings for Atmel Flexcom (Flexible Serial Communication Unit)
> +
> +maintainers:
> +  - Rob Herring <robh+dt@kernel.org>

Person with access to hardware/datasheet/knowledge should be here, not
DT bindings maintainer.

> +
> +description: |

No need for "|"

> +  The Atmel Flexcom is just a wrapper which embeds a SPI controller,
> +  an I2C controller and an USART. Only one function can be used at a
> +  time and is chosen at boot time according to the device tree.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - atmel,sama5d2-flexcom
> +
> +  reg:
> +    minItems: 1

no need for minItems

> +    items:
> +      - description: Flexcom registers

Description is obvious, so just replace all three lines with
	maxItems: 1

> +
> +  clocks:
> +    maxItems: 1
> +
> +  "#address-cells": true
> +
> +  "#size-cells": true


These should have some fixed value (e.g. const: 1).
Second question - they do not look valid since you do not have any
children nodes. It looks like you want children, so you need to define them.

> +
> +  ranges:
> +    description:
> +      One range for the full I/O register region. (including USART,
> +      TWI and SPI registers).
> +    items:
> +      minItems: 3

no need for minItems

> +      maxItems: 3
> +
> +  atmel,flexcom-mode:
> +    description:
> +      One of the values. UART, I2C, SPI.

This does not describe anything.

If you have defines here, mention the header.

> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 1, 2]

Here is 0 not UART?

> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - "#address-cells"
> +  - "#size-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    flx0: flexcom@f8034000 {> +          compatible = "atmel,sama5d2-flexcom";
> +          reg = <0xf8034000 0x200>;
> +          clocks = <&flx0_clk>;
> +          #address-cells = <1>;
> +          #size-cells = <1>;

No need for address/size - no children here.

> +          ranges = <0x0 0xf8034000 0x800>;

Why do you need ranges without children?


Best regards,
Krzysztof