[PATCH v3 1/5] dt-bindings: rtc: Add pinctrl for S35390A

[Rob Herring]

On Wed, Aug 05, 2026 at 07:32:27PM +0000, Markus Probst wrote:
> Synology NAS devices use the output pin for interrupt signal 1 to wake up
> the system.
> 
> Move devicetree bindings for sii,s35390a into its own file.
> Add necessary properties to configure the individual pins via pinctrl,
> which allows the interrupt signal 1 to be used for wakeup alarm.
> 
> Signed-off-by: Markus Probst <markus.probst at posteo.de>
> ---
>  .../devicetree/bindings/rtc/sii,s35390a.yaml       | 109 +++++++++++++++++++++
>  .../devicetree/bindings/rtc/trivial-rtc.yaml       |   3 -
>  MAINTAINERS                                        |   1 +
>  3 files changed, 110 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/rtc/sii,s35390a.yaml b/Documentation/devicetree/bindings/rtc/sii,s35390a.yaml
> new file mode 100644
> index 000000000000..0355f17f233a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/rtc/sii,s35390a.yaml
> @@ -0,0 +1,109 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/rtc/sii,s35390a.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: S-35390A 2-WIRE REAL-TIME CLOCK
> +
> +maintainers:
> +  - Alexandre Belloni <alexandre.belloni at bootlin.com>

This should be someone with the h/w, not subsystem maintainer.

> +
> +description:
> +  The S-35390A is a CMOS 2-wire real-time clock IC which operates with the
> +  very low current consumption in the wide range of operation voltage.
> +
> +allOf:
> +  - $ref: rtc.yaml#
> +
> +properties:
> +  compatible:
> +    const: sii,s35390a
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    minItems: 1
> +    maxItems: 2
> +    description: Supports up to 2 interrupt lines via the INT1 and INT2 pins.
> +
> +  wakeup-parent: true
> +
> +  wakeup-source: true
> +
> +  "#clock-cells":
> +    const: 1
> +
> +patternProperties:
> +  "^pins":

Do you need wild cards here? Wouldn't just 'pins' for the node name be 
fine?

> +    type: object
> +    patternProperties:
> +      "-pins$":
> +        type: object
> +        properties:
> +          pins:
> +            $ref: /schemas/pinctrl/pinmux-node.yaml#/properties/pins
> +            items:
> +              enum:
> +                - int1
> +                - int2
> +
> +          function:
> +            $ref: /schemas/types.yaml#/definitions/string
> +            description: |
> +              Pin function:
> +              - ignore:  Preserve the previous state.
> +              - disable: Disable pin output.
> +              - wakeup:  Output wakes up the system.
> +              - clock:   Output clock pulse.
> +              - pmin1:   Minute periodical output with 50% duty.
> +              - pmin2:   Minute periodical output L for 7.81 ms.
> +                         Can only be used with pin int1.
> +            enum:
> +              - ignore
> +              - disable
> +              - wakeup
> +              - clock
> +              - pmin1
> +              - pmin2
> +
> +        required:
> +          - function
> +
> +        additionalProperties: false
> +
> +    additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        rtc at 30 {
> +            compatible = "sii,s35390a";
> +            reg = <0x30>;
> +            pinctrl-0 = <&rtc_pins_default>;
> +            pinctrl-names = "default";
> +
> +            wakeup-parent = <&int>;
> +
> +            rtc_pins_default: pins {
> +              int1-pins {
> +                pins = "int1";
> +                function = "wakeup";
> +              };
> +              int2-pins {
> +                pins = "int2";
> +                function = "disable";
> +              };
> +            };
> +        };
> +    };
> diff --git a/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml b/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml
> index f4d0eed98a08..7b3f682ef4d5 100644
> --- a/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/trivial-rtc.yaml
> @@ -81,8 +81,6 @@ properties:
>        - ricoh,rv5c386
>        # I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
>        - ricoh,rv5c387a
> -      # 2-wire CMOS real-time clock
> -      - sii,s35390a
>        # ST SPEAr Real-time Clock
>        - st,spear600-rtc
>        # VIA/Wondermedia VT8500 Real-time Clock
> @@ -105,5 +103,4 @@ required:
>    - reg
>  
>  additionalProperties: false
> -
>  ...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 5114e6db7307..4c8bc35cfe55 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -22695,6 +22695,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux.git
>  F:	Documentation/admin-guide/rtc.rst
>  F:	Documentation/devicetree/bindings/rtc/
>  F:	drivers/rtc/
> +F:	include/dt-bindings/rtc/
>  F:	include/linux/rtc.h
>  F:	include/linux/rtc/
>  F:	include/uapi/linux/rtc.h
> 
> -- 
> 2.54.0
>