Re: [PATCH v2 1/2] dt-bindings: memory: document Renesas RPC-IF bindings

[Rob Herring <robh@xxxxxxxxxx>]

On Thu, Apr 30, 2020 at 11:47:25PM +0300, Sergei Shtylyov wrote:
> Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI flash or
> HyperFlash connected to the SoC to be accessed via the external address
> space read mode or the manual mode.
> 
> Document the device tree bindings for the Renesas RPC-IF found in the R-Car
> gen3 SoCs.
> 
> Based on the original patch by Mason Yang <masonccyang@xxxxxxxxxxx>.
> 
> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx>
> 
> ---
> Changes in version 2:
> - rewrote the bindings in YAML.
> 
>  Documentation/devicetree/bindings/memory-controllers/renesas,rpc-if.yaml |   88 ++++++++++

Not where we normally put SPI flash controllers...

>  1 file changed, 88 insertions(+)
> 
> Index: linux/Documentation/devicetree/bindings/memory-controllers/renesas,rpc-if.yaml
> ===================================================================
> --- /dev/null
> +++ linux/Documentation/devicetree/bindings/memory-controllers/renesas,rpc-if.yaml
> @@ -0,0 +1,88 @@
> +# SPDX-License-Identifier: (GPL-2.0)

Dual license new bindings:

(GPL-2.0-only OR BSD-2-Clause)

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/memory-controllers/renesas,rpc-if.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas Reduced Pin Count Interface (RPC-IF)
> +
> +maintainers:
> +  - Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx>
> +
> +description: |
> +  Renesas RPC-IF allows a SPI flash or HyperFlash connected to the SoC to
> +  be accessed via the external address space read mode or the manual mode.
> +
> +  The flash chip itself should be represented by a subnode of the RPC-IF node.
> +  The flash interface is selected based on the "compatible" property of this
> +  subnode:
> +  - if it contains "jedec,spi-nor", then SPI is used;
> +  - if it contains "cfi-flash", then HyperFlash is used.
> +
> +allOf:
> +  - $ref: "/schemas/spi/spi-controller.yaml#"
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +        renesas,r8a77980-rpc-if # device is a part of R8A77980 SoC
> +	renesas,r8a77995-rpc-if # device is a part of R8A77995 SoC

Not valid yaml with tab and not valid json-schema as 'enum' is a list 
(needs '-').

> +      - enum:
> +        renesas,rcar-gen3-rpc-if # a generic R-Car gen3 device
> +
> +  reg:
> +    items:
> +       - description: RPC-IF registers
> +       - description: direct mapping read mode area
> +       - description: write buffer area

Wrong indentation.

> +
> +  reg-names:
> +    items:
> +      - const: regs
> +      - const: dirmap
> +      - const: wbuf
> +
> +  clocks:
> +    maxItems: 1
> +
> +  power-domains:
> +    maxItems: 1
> +
> +  resets:
> +    maxItems: 1
> +
> +patternProperties:
> +  "^.*@[0-9a-f]+$":

^flash@... if you're that restrictive.

> +    type: object
> +    properties:
> +      compatible:
> +        oneOf:
> +          - const: cfi-flash
> +          - const: jedec,spi-nor

enum is better than oneOf+const.

> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/renesas-cpg-mssr.h>
> +    #include <dt-bindings/power/r8a77995-sysc.h>
> +
> +    spi@ee200000 {
> +      compatible = "renesas,r8a77995-rpc-if", "renesas,rcar-gen3-rpc-if";
> +      reg = <0 0xee200000 0 0x200>,
> +            <0 0x08000000 0 0x4000000>,
> +            <0 0xee208000 0 0x100>;
> +      reg-names = "regs", "dirmap", "wbuf";
> +      clocks = <&cpg CPG_MOD 917>;
> +      power-domains = <&sysc R8A77995_PD_ALWAYS_ON>;
> +      resets = <&cpg 917>;
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      flash@0 {
> +        compatible = "jedec,spi-nor";
> +        reg = <0>;
> +        spi-max-frequency = <40000000>;
> +        spi-tx-bus-width = <1>;
> +        spi-rx-bus-width = <1>;
> +      };
> +    };