From: AKASHI Takahiro <takahiro.akashi@linaro.org>
Add a dt binding for the gpio-by-pinctrl driver. The driver is used
for doing GPIO over the SCMI pinctrl protocol. There are a few
mandatory properties such as gpio-ranges and ngpios, but it's not
mandatory to specify the pin-mux.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Linus Walleij <linusw@kernel.org>
---
v4: Changed additionalProperties: true to false.
My concern here was that there might be a lot of gpio properties
which I wasn't familiar with. To check I did:
grep :$ Documentation/devicetree/bindings/gpio/* | \
cut -d : -f 2- | perl -ne 's/[\ ]*//g; print "$_\n"' | \
sort | uniq -c
The only property that I decided to add was gpio-line-names.
Deleted the extra bonus example.
.../bindings/gpio/pin-control-gpio.yaml | 59 +++++++++++++++++++
1 file changed, 59 insertions(+)
create mode 100644 Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml
diff --git a/Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml b/Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml
new file mode 100644
index 000000000000..ebc3fdd039fd
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/pin-control-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Pin control based generic GPIO controller
+
+description:
+ The pin control-based GPIO will facilitate a pin controller's ability
+ to drive electric lines high/low and other generic properties of a
+ pin controller to perform general-purpose one-bit binary I/O.
+
+maintainers:
+ - Dan Carpenter <dan.carpenter@linaro.og>
+
+properties:
+ compatible:
+ const: scmi-pinctrl-gpio
+
+ gpio-controller: true
+
+ "#gpio-cells":
+ const: 2
+
+ gpio-line-names: true
+
+ gpio-ranges: true
+
+ ngpios: true
+
+patternProperties:
+ "^.+-hog(-[0-9]+)?$":
+ type: object
+
+ required:
+ - gpio-hog
+
+required:
+ - compatible
+ - gpio-controller
+ - "#gpio-cells"
+ - gpio-ranges
+ - ngpios
+
+additionalProperties: false
+
+examples:
+ - |
+ gpio {
+ compatible = "scmi-pinctrl-gpio";
+ gpio-controller;
+ #gpio-cells = <2>;
+ ngpios = <3>;
+ gpio-line-names = "gpio_5_17", "gpio_5_20", "gpio_5_22", "gpio_2_1";
+ gpio-ranges = <&scmi_pinctrl 0 30 4>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&keys_pins>;
+ };
--
2.51.0On Tue, Mar 17, 2026 at 05:40:57PM +0300, Dan Carpenter wrote:
> From: AKASHI Takahiro <takahiro.akashi@linaro.org>
>
> Add a dt binding for the gpio-by-pinctrl driver. The driver is used
Drop all references to the driver. Describe the
device/hardware/firmware/interface, not driver. Same for subject.
> for doing GPIO over the SCMI pinctrl protocol. There are a few
> mandatory properties such as gpio-ranges and ngpios, but it's not
> mandatory to specify the pin-mux.
There is no such thing there as pin-mux, so I don't understand above
sentence.
Describe the hardware/firmware/interface, not the patch, because we
easily see which properties are mandatory. Schema tells that.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> Reviewed-by: Linus Walleij <linusw@kernel.org>
A nit, subject: drop second/last, redundant "bindings for". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v6.17-rc3/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
> ---
> v4: Changed additionalProperties: true to false.
>
> My concern here was that there might be a lot of gpio properties
> which I wasn't familiar with. To check I did:
> grep :$ Documentation/devicetree/bindings/gpio/* | \
> cut -d : -f 2- | perl -ne 's/[\ ]*//g; print "$_\n"' | \
> sort | uniq -c
> The only property that I decided to add was gpio-line-names.
>
> Deleted the extra bonus example.
>
> .../bindings/gpio/pin-control-gpio.yaml | 59 +++++++++++++++++++
> 1 file changed, 59 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml
>
> diff --git a/Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml b/Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml
> new file mode 100644
> index 000000000000..ebc3fdd039fd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/pin-control-gpio.yaml
> @@ -0,0 +1,59 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/gpio/pin-control-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Pin control based generic GPIO controller
> +
> +description:
> + The pin control-based GPIO will facilitate a pin controller's ability
> + to drive electric lines high/low and other generic properties of a
> + pin controller to perform general-purpose one-bit binary I/O.
> +
> +maintainers:
> + - Dan Carpenter <dan.carpenter@linaro.og>
> +
> +properties:
> + compatible:
> + const: scmi-pinctrl-gpio
> +
> + gpio-controller: true
> +
> + "#gpio-cells":
> + const: 2
> +
> + gpio-line-names: true
> +
> + gpio-ranges: true
> +
> + ngpios: true
> +
> +patternProperties:
> + "^.+-hog(-[0-9]+)?$":
> + type: object
> +
> + required:
> + - gpio-hog
> +
> +required:
> + - compatible
> + - gpio-controller
> + - "#gpio-cells"
> + - gpio-ranges
> + - ngpios
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + gpio {
> + compatible = "scmi-pinctrl-gpio";
> + gpio-controller;
> + #gpio-cells = <2>;
> + ngpios = <3>;
Three pins here
> + gpio-line-names = "gpio_5_17", "gpio_5_20", "gpio_5_22", "gpio_2_1";
... four here
> + gpio-ranges = <&scmi_pinctrl 0 30 4>;
... and four here, so it feels inconsistent. I guess ngpios = 4?
Best regards,
Krzysztof
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