Re: [PATCH v3 1/2] dt-bindings: memory: document Renesas RPC-IF bindings

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Sergei,

On Mon, May 18, 2020 at 10:33 PM Sergei Shtylyov
<sergei.shtylyov@xxxxxxxxxxxxxxxxxx> 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>

Thanks for your patch!

> --- /dev/null
> +++ linux/Documentation/devicetree/bindings/memory-controllers/renesas,rpc-if.yaml
> @@ -0,0 +1,88 @@
> +# SPDX-License-Identifier: (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

Usually we add a comment with the SoC name, e.g. "# R-Car V3H"

> +        - renesas,r8a77995-rpc-if
> +      - enum:
> +        - renesas,rcar-gen3-rpc-if # a generic R-Car gen3 device

No need for an enum, just use "- const: renesas,rcar-gen3-rpc-if".

> +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>;

Examples are built with #{address,size}-cells = <1>, so please drop
the zeroes.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds