Re: [PATCH v3 5/8] dt-bindings: snps,dw-apb-ssi: Add sparx5 support, plus snps,rx-sample-delay-ns property

From: Rob Herring <robh@kernel.org>
To: Lars Povlsen <lars.povlsen@microchip.com>
Cc: Mark Brown <broonie@kernel.org>, Peter Rosin <peda@axentia.se>,
	Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>,
	linux-spi@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	Serge Semin <fancer.lancer@gmail.com>,
	Serge Semin <Sergey.Semin@baikalelectronics.ru>
Subject: Re: [PATCH v3 5/8] dt-bindings: snps,dw-apb-ssi: Add sparx5 support, plus snps,rx-sample-delay-ns property
Date: Mon, 13 Jul 2020 13:22:59 -0600	[thread overview]
Message-ID: <20200713192259.GA553903@bogus> (raw)
In-Reply-To: <20200702101331.26375-6-lars.povlsen@microchip.com>

On Thu, Jul 02, 2020 at 12:13:28PM +0200, Lars Povlsen wrote:
> This has the following changes for the snps,dw-apb-ss DT bindings:
> 
> - Add "microchip,sparx5-spi" as the compatible for the Sparx5 SoC
>   controller
> 
> - Add the property "mux-controls" for the above compatible string
> 
> - Add the property "snps,rx-sample-delay-ns" for SPI slaves
> 
> Signed-off-by: Lars Povlsen <lars.povlsen@microchip.com>
> ---
>  .../bindings/spi/snps,dw-apb-ssi.yaml         | 28 +++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> index c62cbe79f00dd..9d9208391fae3 100644
> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> @@ -36,6 +36,8 @@ properties:
>                - mscc,ocelot-spi
>                - mscc,jaguar2-spi
>            - const: snps,dw-apb-ssi
> +      - description: Microchip Sparx5 SoC SPI Controller
> +        const: microchip,sparx5-spi
>        - description: Amazon Alpine SPI Controller
>          const: amazon,alpine-dw-apb-ssi
>        - description: Renesas RZ/N1 SPI Controller
> @@ -93,6 +95,19 @@ properties:
>        - const: tx
>        - const: rx
> 
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        const: microchip,sparx5-spi
> +
> +then:
> +  properties:
> +    mux-controls:
> +      description: A mux controller node for selecting SPI bus interface.
> +      maxItems: 1
> +      $ref: '/schemas/types.yaml#/definitions/phandle'

Can drop the type. You can assume common properties already have a 
defined type.

> +
>  patternProperties:
>    "^.*@[0-9a-f]+$":
>      type: object
> @@ -107,6 +122,14 @@ patternProperties:
>        spi-tx-bus-width:
>          const: 1
> 
> +      snps,rx-sample-delay-ns:

We already have 'rx-sample-delay-ns' from Rockchip SPI, so use that. But 
note that it applies to the SPI node. Does this need to be per SPI 
child?

BTW, the Rockchip controller appears to be a version of the DW 
controller.

> +        description: SPI Rx sample delay offset, unit is nanoseconds.
> +          The delay from the default sample time before the actual
> +          sample of the rxd input signal occurs. The "rx_sample_delay"
> +          is an optional feature of the designware controller, and the
> +          upper limit is also subject to controller configuration.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +
>  unevaluatedProperties: false
> 
>  required:
> @@ -129,5 +152,10 @@ examples:
>        num-cs = <2>;
>        cs-gpios = <&gpio0 13 0>,
>                   <&gpio0 14 0>;
> +      spi-flash@1 {
> +        compatible = "spi-nand";
> +        reg = <1>;
> +        snps,rx-sample-delay-ns = <7>;
> +      };
>      };
>  ...
> --
> 2.27.0