[v3,2/9] dt-bindings: spi: Add Tegra Quad SPI device tree binding

This patch adds YAML based device tree binding document for Tegra
Quad SPI driver.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 .../bindings/spi/nvidia,tegra210-quad.yaml         | 130 +++++++++++++++++++++
 1 file changed, 130 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/nvidia,tegra210-quad.yaml

On Fri, Dec 11, 2020 at 01:15:56PM -0800, Sowjanya Komatineni wrote:
> This patch adds YAML based device tree binding document for Tegra
> Quad SPI driver.
> 
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
>  .../bindings/spi/nvidia,tegra210-quad.yaml         | 130 +++++++++++++++++++++
>  1 file changed, 130 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/spi/nvidia,tegra210-quad.yaml
> 
> diff --git a/Documentation/devicetree/bindings/spi/nvidia,tegra210-quad.yaml b/Documentation/devicetree/bindings/spi/nvidia,tegra210-quad.yaml
> new file mode 100644
> index 0000000..0b5fea6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spi/nvidia,tegra210-quad.yaml
> @@ -0,0 +1,130 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/spi/nvidia,tegra210-quad.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Tegra Quad SPI Controller
> +
> +maintainers:
> +  - Thierry Reding <thierry.reding@gmail.com>
> +  - Jonathan Hunter <jonathanh@nvidia.com>

allOf:
  - $ref: spi-controller.yaml#

> +
> +properties:
> +  compatible:
> +    enum:
> +      - nvidia,tegra210-qspi
> +      - nvidia,tegra186-qspi
> +      - nvidia,tegra194-qspi
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clock-names:
> +    items:
> +      - const: qspi
> +      - const: qspi_out
> +
> +  clocks:
> +    maxItems: 2
> +
> +  resets:
> +    maxItems: 1
> +
> +  dmas:
> +    maxItems: 2
> +
> +  dma-names:
> +    items:
> +      - const: rx
> +      - const: tx
> +
> +patternProperties:
> +  "^.*@[0-9a-f]+":

You can drop '^.*'.

> +    type: object
> +
> +    properties:
> +      compatible:
> +        description:
> +          Compatible of the SPI device.
> +
> +      reg:
> +        maxItems: 1
> +
> +      spi-max-frequency:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description:
> +          Maximum Quad SPI clocking speed of the device in Hz.
> +
> +      spi-rx-bus-width:
> +        description:
> +          Bus width to the Quad SPI bus used for read transfers.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        enum: [1, 2, 4]
> +
> +      spi-tx-bus-width:
> +        description:
> +          Bus width to the Quad SPI bus used for write transfers.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        enum: [1, 2, 4]

All of the above 5 properties are covered by spi-controller.yaml. You 
only need additional constraints here. As 8-bit mode is not supported, 
you need:

spi-tx-bus-width:
  enum: [1, 2, 4]

> +
> +      nvidia,tx-clk-tap-delay:
> +        description:
> +          Delays the clock going out to device with this tap value.
> +          Tap value varies based on platform design trace lengths from Tegra
> +          QSPI to corresponding slave device.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        minimum: 0
> +        maximum: 31
> +
> +      nvidia,rx-clk-tap-delay:
> +        description:
> +          Delays the clock coming in from the device with this tap value.
> +          Tap value varies based on platform design trace lengths from Tegra
> +          QSPI to corresponding slave device.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        minimum: 0
> +        maximum: 255

Please include these properties in your example.

> +
> +    required:
> +      - reg
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clock-names
> +  - clocks
> +  - resets
> +
> +additionalProperties: true

That's generally wrong unless it's a schema to be included by other 
schemas.

unevaluatedProperties: false

> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/tegra210-car.h>
> +    #include <dt-bindings/reset/tegra210-car.h>
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    spi@70410000 {
> +            compatible = "nvidia,tegra210-qspi";
> +            reg = <0x70410000 0x1000>;
> +            interrupts = <GIC_SPI 10 IRQ_TYPE_LEVEL_HIGH>;
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +            clocks = <&tegra_car TEGRA210_CLK_QSPI>,
> +                     <&tegra_car TEGRA210_CLK_QSPI_PM>;
> +            clock-names = "qspi", "qspi_out";
> +            resets = <&tegra_car 211>;
> +            dmas = <&apbdma 5>, <&apbdma 5>;
> +            dma-names = "rx", "tx";
> +
> +            flash@0 {
> +                    compatible = "spi-nor";
> +                    reg = <0>;
> +                    spi-max-frequency = <104000000>;
> +                    spi-tx-bus-width = <2>;
> +                    spi-rx-bus-width = <2>;
> +            };
> +    };
> -- 
> 2.7.4
>