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

From: Krzysztof Kozlowski
Date: Tue May 03 2022 - 08:34:49 EST


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@xxxxxxxxxxxxx>
> ---
> .../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@xxxxxxxxxx>

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