Re: [PATCH 3/4] dt-bindings: spi: add binding doc for spi-mtk-snfi

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

On 03/04/2022 15:11, Chuanhong Guo wrote:
> Add device-tree binding documentation for Mediatek SPI-NAND Flash
> Interface.

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

> 
> Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
> ---
>  .../bindings/spi/mediatek,spi-mtk-snfi.yaml   | 87 +++++++++++++++++++
>  1 file changed, 87 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml b/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml
> new file mode 100644
> index 000000000000..166c6b50b9d1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml
> @@ -0,0 +1,87 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/spi/mediatek,spi-mtk-snfi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SPI-NAND flash controller for MediaTek ARM SoCs
> +
> +maintainers:
> +  - Chuanhong Guo <gch981213@gmail.com>
> +
> +description: |
> +  The Mediatek SPI-NAND flash controller is an extended version of
> +  the Mediatek NAND flash controller. It can perform standard SPI
> +  instructions with one continuous write and one read for up-to 0xa0
> +  bytes. It also supports typical SPI-NAND page cache operations
> +  in single, dual or quad IO mode with piplined ECC encoding/decoding
> +  using the accompanying ECC engine. There should be only one spi
> +  slave device following generic spi bindings.
> +
> +allOf:
> +  - $ref: /schemas/spi/spi-controller.yaml#
> +
> +properties:
> +  compatible:
> +    enum:
> +      - mediatek,mt7622-snand
> +      - mediatek,mt7629-snand

One blank line, please.

> +  reg:
> +    items:
> +      - description: core registers
> +
> +  interrupts:
> +    items:
> +      - description: NFI interrupt
> +
> +  clocks:
> +    items:
> +      - description: clock used for the controller
> +      - description: clock used for the SPI bus
> +
> +  clock-names:
> +    items:
> +      - const: nfi_clk
> +      - const: pad_clk
> +
> +  ecc-engine:

The nand-chip.yaml defines a nand-ecc-engine, so how about using that
one? I know mtk-nand.txt uses ecc-engine, but for new schema better to
use properties from existing YAML.

> +    description: device-tree node of the accompanying ECC engine.
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +

Rest looks good, thank you!


Best regards,
Krzysztof