Re: [PATCH v3 4/9] dt-bindings: pinctrl: Add Nuvoton WPCM450

[Rob Herring <robh@xxxxxxxxxx>]

On Fri, Dec 24, 2021 at 09:09:30PM +0100, Jonathan Neuschäfer wrote:
> This binding is heavily based on the one for NPCM7xx, because the
> hardware is similar. There are some notable differences, however:
> 
> - The addresses of GPIO banks are not physical addresses but simple
>   indices (0 to 7), because the GPIO registers are not laid out in
>   convenient blocks.
> - Pinmux settings can explicitly specify that the GPIO mode is used.
> 
> Certain pins support blink patterns in hardware. This is currently not
> modelled in the DT binding.
> 
> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@xxxxxxx>
> 
> 
> ---
> v3:
> - Make changes suggested by Rob Herring
> - Fix lint errors
> - Simplify child node patterns
> - Remove if/type=object/then trick
> - Reduce interrupts.maxItems to 3: 4 aren't necessary
> - Replace list of gpio0/1/2/etc. with pattern
> - Remove nuvoton,interrupt-map again, to simplify the binding
> - Make tuples clearer
> 
> v2:
> - https://lore.kernel.org/lkml/20211207210823.1975632-5-j.neuschaefer@xxxxxxx/
> - Move GPIO into subnodes
> - Improve use of quotes
> - Remove unnecessary minItems/maxItems lines
> - Remove "phandle: true"
> - Use separate prefixes for pinmux and pincfg nodes
> - Add nuvoton,interrupt-map property
> - Make it possible to set pinmux to GPIO explicitly
> 
> v1:
> - https://lore.kernel.org/lkml/20210602120329.2444672-5-j.neuschaefer@xxxxxxx/
> ---
>  .../pinctrl/nuvoton,wpcm450-pinctrl.yaml      | 159 ++++++++++++++++++
>  1 file changed, 159 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pinctrl/nuvoton,wpcm450-pinctrl.yaml
> 
> diff --git a/Documentation/devicetree/bindings/pinctrl/nuvoton,wpcm450-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/nuvoton,wpcm450-pinctrl.yaml
> new file mode 100644
> index 0000000000000..2d15737b5815e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pinctrl/nuvoton,wpcm450-pinctrl.yaml
> @@ -0,0 +1,159 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pinctrl/nuvoton,wpcm450-pinctrl.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Nuvoton WPCM450 pin control and GPIO
> +
> +maintainers:
> +  - Jonathan Neuschäfer <j.neuschaefer@xxxxxxx>
> +
> +properties:
> +  compatible:
> +    const: nuvoton,wpcm450-pinctrl
> +
> +  reg:
> +    maxItems: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +patternProperties:
> +  # There are three kinds of subnodes:
> +  # 1. a GPIO controller node for each GPIO bank
> +  # 2. a pinmux node configures pin muxing for a group of pins (e.g. rmii2)
> +  # 3. a pinconf node configures properties of a single pin
> +
> +  "^gpio":

'^gpio@[0-7]$'

> +    type: object
> +
> +    description:
> +      Eight GPIO banks (gpio@0 to gpio@7), that each contain between 14 and 18
> +      GPIOs. Some GPIOs support interrupts.
> +
> +    properties:
> +      reg:
> +        description: GPIO bank number (0-7)

reg:
  minimum: 0
  maximum: 7

But there's not an actual register address range you could use instead?

> +
> +      gpio-controller: true
> +
> +      "#gpio-cells":
> +        const: 2
> +
> +      interrupt-controller: true
> +
> +      "#interrupt-cells":
> +        const: 2
> +
> +      interrupts:
> +        maxItems: 3
> +        description:
> +          The interrupts associated with this GPIO bank
> +
> +    required:
> +      - reg
> +      - gpio-controller
> +      - '#gpio-cells'
> +
> +  "^mux-":
> +    $ref: pinmux-node.yaml#
> +
> +    properties:
> +      groups:
> +        description:
> +          One or more groups of pins to mux to a certain function
> +        items:
> +          enum: [ smb3, smb4, smb5, scs1, scs2, scs3, smb0, smb1, smb2, bsp,
> +                  hsp1, hsp2, r1err, r1md, rmii2, r2err, r2md, kbcc, dvo,
> +                  clko, smi, uinc, gspi, mben, xcs2, xcs1, sdio, sspi, fi0,
> +                  fi1, fi2, fi3, fi4, fi5, fi6, fi7, fi8, fi9, fi10, fi11,
> +                  fi12, fi13, fi14, fi15, pwm0, pwm1, pwm2, pwm3, pwm4, pwm5,
> +                  pwm6, pwm7, hg0, hg1, hg2, hg3, hg4, hg5, hg6, hg7 ]
> +      function:
> +        description:
> +          The function that a group of pins is muxed to
> +        enum: [ smb3, smb4, smb5, scs1, scs2, scs3, smb0, smb1, smb2, bsp,
> +                hsp1, hsp2, r1err, r1md, rmii2, r2err, r2md, kbcc, dvo0,
> +                dvo1, dvo2, dvo3, dvo4, dvo5, dvo6, dvo7, clko, smi, uinc,
> +                gspi, mben, xcs2, xcs1, sdio, sspi, fi0, fi1, fi2, fi3, fi4,
> +                fi5, fi6, fi7, fi8, fi9, fi10, fi11, fi12, fi13, fi14, fi15,
> +                pwm0, pwm1, pwm2, pwm3, pwm4, pwm5, pwm6, pwm7, hg0, hg1,
> +                hg2, hg3, hg4, hg5, hg6, hg7, gpio ]
> +
> +    dependencies:
> +      groups: [ function ]
> +      function: [ groups ]
> +
> +    additionalProperties: false
> +
> +  "^cfg-":
> +    $ref: pincfg-node.yaml#
> +
> +    properties:
> +      pins:
> +        description:
> +          A list of pins to configure in certain ways, such as enabling
> +          debouncing
> +        items:
> +          pattern: "^gpio1?[0-9]{1,2}$"
> +
> +      input-debounce: true
> +
> +    additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/gpio/gpio.h>
> +    pinctrl: pinctrl@b8003000 {
> +      compatible = "nuvoton,wpcm450-pinctrl";
> +      reg = <0xb8003000 0x1000>;
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      gpio0: gpio@0 {
> +        reg = <0>;
> +        gpio-controller;
> +        #gpio-cells = <2>;
> +        interrupts = <2 IRQ_TYPE_LEVEL_HIGH>,
> +                     <3 IRQ_TYPE_LEVEL_HIGH>,
> +                     <4 IRQ_TYPE_LEVEL_HIGH>;
> +      };
> +
> +      mux-rmii2 {
> +        groups = "rmii2";
> +        function = "rmii2";
> +      };
> +
> +      pinmux_uid: mux-uid {
> +        groups = "gspi", "sspi";
> +        function = "gpio";
> +      };
> +
> +      pinctrl_uid: cfg-uid {
> +        pins = "gpio14";
> +        input-debounce = <1>;
> +      };
> +    };
> +
> +    gpio-keys {
> +      compatible = "gpio-keys";
> +      pinctrl-names = "default";
> +      pinctrl-0 = <&pinctrl_uid>, <&pinmux_uid>;
> +
> +      uid {
> +        label = "UID";
> +        linux,code = <102>;
> +        gpios = <&gpio0 14 GPIO_ACTIVE_HIGH>;
> +      };
> +    };
> --
> 2.30.2
> 
>