Re: [PATCH v4 04/14] dt-bindings: rtc: add bindings for microchip mpfs rtc

[Rob Herring <robh@xxxxxxxxxx>]

On Mon, Jan 17, 2022 at 11:07:45AM +0000, conor.dooley@xxxxxxxxxxxxx wrote:
> From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> 
> Add device tree bindings for the real time clock on
> the Microchip PolarFire SoC.
> 
> Signed-off-by: Daire McNamara <daire.mcnamara@xxxxxxxxxxxxx>
> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> ---
>  .../bindings/rtc/microchip,mfps-rtc.yaml      | 63 +++++++++++++++++++
>  1 file changed, 63 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
> 
> diff --git a/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml b/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
> new file mode 100644
> index 000000000000..d57460cbe5e3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
> @@ -0,0 +1,63 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/rtc/microchip,mfps-rtc.yaml#
> +
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip PolarFire Soc (MPFS) RTC Device Tree Bindings
> +
> +allOf:
> +  - $ref: rtc.yaml#
> +
> +maintainers:
> +  - Daire McNamara <daire.mcnamara@xxxxxxxxxxxxx>
> +  - Lewis Hanly <lewis.hanly@xxxxxxxxxxxxx>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - microchip,mpfs-rtc
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 2

Need to define what each one is.

> +
> +  microchip,prescaler:
> +    description: |
> +      The prescaler divides the input frequency to create a time-based strobe (typically 1 Hz) for
> +      the calendar counter. The Alarm and Compare Registers, in conjunction with the calendar
> +      counter, facilitate time-matched events. To properly operate in Calendar or Binary mode,
> +      the 26-bit prescaler must be programmed to generate a strobe to the RTC.
> +    maxItems: 1
> +    $ref: /schemas/types.yaml#/definitions/uint32

Can't you calculate this based on the clock input freq?

> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    items:
> +      - const: rtc
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/microchip,mpfs-clock.h>
> +    rtc@20124000 {
> +        compatible = "microchip,mpfs-rtc";
> +        reg = <0x20124000 0x1000>;
> +        clocks = <&clkcfg CLK_RTC>;
> +        clock-names = "rtc";
> +        interrupts = <80>, <81>;
> +    };
> +...
> -- 
> 2.32.0
> 
>