Re: [PATCHv2] dt-bindings: pinctrl: convert nsp-gpio binding

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] dt-bindings: validation failure due to top-level additionalProperties restricting scalar properties
- [Medium] dt-bindings: missing constraint in nsp-gpio-pinconf bypasses typo validation
--

commit 7f4d084d5f13cdd135dd4287165b9406e5c21963
Author: Rosen Penev <rosenp@gmail.com>

dt-bindings: pinctrl: convert nsp-gpio binding

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.

> 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 0000000000000..d7f9a1eb3b93d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.yaml

[ ... ]

> +$defs:
> +  nsp-gpio-pinconf:
> +    type: object
> +    allOf:
> +      - $ref: pincfg-node.yaml#
> +      - $ref: pinmux-node.yaml#

[Severity: Medium]
Will this allow misspelled or unsupported properties inside pin configuration
child nodes to pass validation?

Because neither additionalProperties: false nor unevaluatedProperties: false
is specified in this definition, the object schema relies on default JSON
schema behavior, which permits arbitrary undefined properties. Properties like
bias-pullup (typo) or slew-rate (unsupported) will pass dtbs_check
without warning.

[ ... ]

> +additionalProperties:
> +  $ref: '#/$defs/nsp-gpio-pinconf'

[Severity: High]
Does this inappropriately apply pinconf constraints to all unmatched top-level
properties?

In JSON Schema, this forces all properties not explicitly listed in the
properties block to conform to $defs/nsp-gpio-pinconf. Since that reference
enforces type: object and requires a pins property, scalar or array
properties will unconditionally fail.

Device trees utilizing this controller and standard generic properties (like
pinctrl-names or implicit ones like phandle) will fail schema validation.

[ ... ]

> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> +    gpio@18000020 {
> +        compatible = "brcm,nsp-gpio-a";
> +        reg = <0x18000020 0x100>,
> +              <0x1803f1c4 0x1c>;
> +        #gpio-cells = <2>;
> +        gpio-controller;
> +        ngpios = <32>;
> +        gpio-ranges = <&pinctrl 0 0 31>;
> +        interrupt-controller;
> +        #interrupt-cells = <2>;
> +        interrupts = <GIC_SPI 85 IRQ_TYPE_LEVEL_HIGH>;
> +
> +        /* Pin configuration node applied as a pinctrl state */
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&led>;

[Severity: High]
Will these standard properties in the example fail validation?

Because of the additionalProperties directive restricting scalar properties,
pinctrl-names and pinctrl-0 will fail validation because they are not
objects and lack a pins property.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260924233541.126868-1-rosenp@gmail.com?part=1