Re: [PATCH v6 04/15] dt-bindings: add BCM6328 pincontroller binding documentation

[Rob Herring <robh+dt@kernel.org>]

On Wed, Mar 10, 2021 at 5:55 AM Álvaro Fernández Rojas
<noltari@gmail.com> wrote:
>
> Add binding documentation for the pincontrol core found in BCM6328 SoCs.
>
> Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
> Co-developed-by: Jonas Gorski <jonas.gorski@gmail.com>
> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
> ---
>  v6: add changes suggested by Rob Herring
>  v5: change Documentation to dt-bindings in commit title
>  v4: no changes
>  v3: add new gpio node
>  v2: remove interrupts
>
>  .../pinctrl/brcm,bcm6328-pinctrl.yaml         | 174 ++++++++++++++++++
>  1 file changed, 174 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pinctrl/brcm,bcm6328-pinctrl.yaml
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/brcm,bcm6328-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/brcm,bcm6328-pinctrl.yaml
> new file mode 100644
> index 000000000000..471f6efa1754
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pinctrl/brcm,bcm6328-pinctrl.yaml
> @@ -0,0 +1,174 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pinctrl/brcm,bcm6328-pinctrl.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Broadcom BCM6328 pin controller
> +
> +maintainers:
> +  - Álvaro Fernández Rojas <noltari@gmail.com>
> +  - Jonas Gorski <jonas.gorski@gmail.com>
> +
> +description: |+
> +  The pin controller node should be the child of a syscon node.
> +
> +  Refer to the the bindings described in
> +  Documentation/devicetree/bindings/mfd/syscon.yaml
> +
> +properties:
> +  compatible:
> +    const: brcm,bcm6328-pinctrl
> +
> +  gpio:
> +    type: object
> +    properties:
> +      compatible:
> +        const: brcm,bcm6328-gpio
> +
> +      data:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: |
> +          Offset in the register map for the data register (in bytes).
> +
> +      dirout:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: |
> +          Offset in the register map for the dirout register (in bytes).
> +
> +      gpio-controller: true
> +
> +      "#gpio-cells":
> +        const: 2
> +
> +      gpio-ranges:
> +        maxItems: 1
> +
> +    required:
> +      - gpio-controller
> +      - gpio-ranges
> +      - '#gpio-cells'
> +
> +    additionalProperties: false
> +
> +patternProperties:
> +  '^.*-pins$':
> +    if:
> +      type: object
> +    then:
> +      properties:
> +        function:
> +          $ref: "pinmux-node.yaml#/properties/function"
> +          enum: [ serial_led_data, serial_led_clk, inet_act_led, pcie_clkreq,
> +                  led, ephy0_act_led, ephy1_act_led, ephy2_act_led,
> +                  ephy3_act_led, hsspi_cs1, usb_device_port, usb_host_port ]
> +
> +        pins:
> +          $ref: "pinmux-node.yaml#/properties/pins"
> +          enum: [ gpio6, gpio7, gpio11, gpio16, gpio17, gpio18, gpio19,
> +                  gpio20, gpio25, gpio26, gpio27, gpio28, hsspi_cs1,
> +                  usb_port1 ]
> +
> +required:
> +  - compatible
> +  - gpio
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    gpio_cntl@10000080 {
> +      compatible = "brcm,bcm6328-gpio-controller", "syscon", "simple-mfd";

You just added "brcm,bcm6328-gpio-controller", it would need to be documented.

> +      reg = <0x10000080 0x80>;
> +
> +      pinctrl: pinctrl {
> +        compatible = "brcm,bcm6328-pinctrl";
> +
> +        gpio {
> +          compatible = "brcm,bcm6328-gpio";

I'm still trying to understand why you need 3 levels of nodes here?
The gpio controller contains a pin controller plus other undefined
functions (because of 'syscon') and the pin controller contains a gpio
controller?

I think "brcm,bcm6328-gpio-controller" and "brcm,bcm6328-pinctrl"
should be a single node.

> +          data = <0xc>;
> +          dirout = <0x4>;

This looks similar to the brcm,bcm6345-gpio.txt binding which then
uses the gpio-mmio driver. Defining addresses with 'reg' is much
preferred over custom properties. That binding also captures the bank
size.

Rob