[PATCH 1/3] spi: dt-bindings: add doc for Amlogic A113L2 SFC

[Krzysztof Kozlowski]

On Fri, Aug 08, 2025 at 10:00:34AM +0800, Xianwei Zhao wrote:
> From: Feng Chen <feng.chen at amlogic.com>
> 
> The Flash Controller is derived by adding an SPI path to the original
> raw NAND controller. This controller supports two modes: raw mode and
> SPI mode. The raw mode has already been implemented in the community,
> and the SPI mode is described here.
> 

Subject: drop doc, so just "Add Amlogic foo ..."

> Add bindings for Amlogic A113L2 SPI Flash Controller.
> 
> Signed-off-by: Feng Chen <feng.chen at amlogic.com>
> Signed-off-by: Xianwei Zhao <xianwei.zhao at amlogic.com>
> ---
>  .../devicetree/bindings/spi/amlogic,a4-spifc.yaml  | 104 +++++++++++++++++++++
>  1 file changed, 104 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/spi/amlogic,a4-spifc.yaml b/Documentation/devicetree/bindings/spi/amlogic,a4-spifc.yaml
> new file mode 100644
> index 000000000000..712a17a4b117
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spi/amlogic,a4-spifc.yaml
> @@ -0,0 +1,104 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2025 Amlogic, Inc. All rights reserved
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/spi/amlogic,a4-spifc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SPI flash controller for Amlogic ARM SoCs
> +
> +maintainers:
> +  - Liang Yang <liang.yang at amlogic.com>
> +  - Feng Chen <feng.chen at amlogic.com>
> +  - Xianwei Zhao <xianwei.zhao at amlogic.com>
> +
> +description:
> +  The Amlogic SPI flash controller is an extended version
> +  of the Amlogic NAND flash controller. It supports SPI Nor
> +  Flash and SPI NAND Flash(where the Host ECC HW engine could
> +  be enabled).

Wrap at coding style, 80.

> +
> +allOf:
> +  - $ref: /schemas/spi/spi-controller.yaml#
> +
> +properties:
> +  compatible:
> +    const: amlogic,a4-spifc
> +
> +  reg:
> +    items:
> +      - description: core registers
> +      - description: parent clk control registers

Why are you poking to parent node or to clock registers? This looks like
mixing up device address spaces.

> +
> +  reg-names:
> +    items:
> +      - const: core
> +      - const: pclk
> +
> +  clocks:
> +    items:
> +      - description: clock gate

Are you sure this is separate clock input to this device?

> +      - description: clock used for the controller
> +      - description: clock used for the SPI bus
> +
> +  clock-names:
> +    items:
> +      - const: gate
> +      - const: core
> +      - const: device
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  amlogic,sfc-enable-random:
> +    description: Enable data scrambling

Why would this be a property of the board?

> +    type: boolean
> +
> +  amlogic,sfc-no-hwecc:
> +    description: Disable ECC HW engine

Same question, why not having ECC always?

> +    type: boolean
> +
> +  amlogic,rx-adj:
> +    description:
> +      Adjust sample timing for RX, Sampling time
> +      move later by 1 bus clock.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 1, 2, 3]
> +    default: 0
> +
> +required:
> +  - compatible
> +  - reg
> +  - reg-names
> +  - clocks
> +  - clock-names
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    sfc0: spi at fe08d000 {
> +      compatible = "amlogic,a4-spifc";
> +      reg = <0xfe08d000 0x800>, <0xfe08c000 0x4>;

One register for the parent clock? This really does not look like part
of this device.

Best regards,
Krzysztof