Re: [PATCH v3] dt-bindings: pinctrl: convert nsp-gpio binding

[Rob Herring <robh@kernel.org>]

On Sun, Sep 27, 2026 at 02:27:48PM -0700, Rosen Penev wrote:
> The brcm,nsp-gpio-a compatible used by the NSP GPIO controller was only
> documented in the legacy text binding, so dtbs_check reported "failed to
> match any schema" for the gpio@20 node present in the bcm958625 and
> related broadcom boards.
> 
> Convert Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.txt to
> a YAML schema and drop the text binding. Keep the existing required and
> optional properties (reg, #gpio-cells, gpio-controller, ngpios, and the
> optional interrupt/gpio-ranges support), including the generic pinconf
> child nodes with pin bias and drive-strength.
> 
> Pin configuration nodes may be direct children of the controller or
> grouped under a "-pins" node; both forms are recognized, and each "-pins"
> node may group further pin configuration children. Child nodes named
> "-hog" are supported as GPIO hogs.
> 
> The generic pinconf and pinmux helper schemas end in
> "additionalProperties: true" and cannot close the node from an in-place
> applicator, so spell out the supported subset and set
> "additionalProperties: false" in the local pin configuration node schema.
> Without it misspelled or unsupported properties such as "bias-pullup" or
> "slew-rate" are silently accepted.
> 
> Controller children are matched with "anyOf" against the pin
> configuration node schema and against "not: { type: object }". The
> latter keeps non-node properties such as #pinctrl-cells or clocks from
> being forced through the pin configuration schema, while still rejecting
> pin configuration child nodes that do not look like one. A plain
> "additionalProperties: false" cannot be used here because it would also
> reject the directly nested pin configuration nodes.
> 
> Assisted-by: LLM
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
>  v3: add additionalProperties
>  v2: don't drop gpio-hog
>  .../bindings/pinctrl/brcm,nsp-gpio.txt        |  80 ----------
>  .../bindings/pinctrl/brcm,nsp-gpio.yaml       | 144 ++++++++++++++++++
>  2 files changed, 144 insertions(+), 80 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.txt
>  create mode 100644 Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.yaml


> diff --git a/Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.yaml b/Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.yaml
> new file mode 100644
> index 000000000000..e5144da1bf57
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.yaml
> @@ -0,0 +1,144 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pinctrl/brcm,nsp-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Broadcom Northstar Plus (NSP) GPIO/PINCONF Controller
> +
> +maintainers:
> +  - Ray Jui <rjui@broadcom.com>
> +  - Scott Branden <sbranden@broadcom.com>
> +
> +description: |
> +  The chipCommonA GPIO block also provides generic pin configuration for the
> +  pins it controls: bias, pull up/down and drive strength. Pin configuration
> +  child nodes may be direct children of the controller, or grouped under a
> +  '-pins' node. In both cases the pin configuration nodes are referenced by
> +  the consuming device through the standard pinctrl-0/pinctrl-names
> +  properties. Child nodes named '*-hog' are treated as GPIO hogs.
> +
> +properties:
> +  compatible:
> +    const: brcm,nsp-gpio-a
> +
> +  reg:
> +    items:
> +      - description: GPIO base registers
> +      - description: IO control registers
> +
> +  "#gpio-cells":
> +    const: 2
> +    description: |
> +      The first cell is the GPIO pin number (within the controller's pin
> +      space) and the second cell is used for the following:
> +      bit[0]: polarity (0 for active high and 1 for active low)
> +
> +  gpio-controller: true
> +
> +  ngpios:
> +    description: Number of GPIOs supported (58x25 supports 32 and 58x23 supports 24)
> +    maximum: 32
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  "#interrupt-cells":
> +    const: 2
> +
> +  interrupt-controller: true
> +
> +  gpio-ranges: true
> +
> +required:
> +  - compatible
> +  - reg
> +  - "#gpio-cells"
> +  - gpio-controller
> +  - ngpios
> +
> +$defs:
> +  nsp-gpio-pinconf:
> +    type: object
> +    allOf:
> +      - $ref: pincfg-node.yaml#
> +      - $ref: pinmux-node.yaml#
> +
> +    properties:
> +      pins:
> +        $ref: /schemas/types.yaml#/definitions/string-array
> +        items:
> +          pattern: '^gpio-'
> +
> +      bias-disable: true
> +      bias-pull-up: true
> +      bias-pull-down: true
> +
> +      drive-strength:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        enum: [ 2, 4, 6, 8, 10, 12, 14, 16 ]
> +
> +    required:
> +      - pins
> +
> +    additionalProperties: false
> +
> +patternProperties:
> +  '-pins$':
> +    oneOf:
> +      - $ref: '#/$defs/nsp-gpio-pinconf'
> +      - type: object
> +        additionalProperties:
> +          $ref: '#/$defs/nsp-gpio-pinconf'
> +
> +  '-hog(-[0-9]+)?$':
> +    type: object
> +    required:
> +      - gpio-hog
> +
> +additionalProperties:
> +  anyOf:
> +    - $ref: '#/$defs/nsp-gpio-pinconf'

This is a superset of what '-pins$' allows in the first oneOf entry. Not 
much point in defining '-pins' if any name is allowed unless '-pins' is 
only for container nodes.

> +    - not:
> +        type: object

sashiko comment is correct here.

Rob