Re: [PATCH 2/2] dt-bindings: mfd: add Broadcom's timer MFD block

[Rob Herring <robh@kernel.org>]

On Fri, Oct 29, 2021 at 10:25:05PM +0200, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
> 
> This block is called timer in documentation but it actually behaves like
> a MFD.
> 
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
>  .../bindings/mfd/brcm,timer-mfd.yaml          | 64 +++++++++++++++++++
>  1 file changed, 64 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/brcm,timer-mfd.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mfd/brcm,timer-mfd.yaml b/Documentation/devicetree/bindings/mfd/brcm,timer-mfd.yaml
> new file mode 100644
> index 000000000000..0060b6c443a7
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/brcm,timer-mfd.yaml
> @@ -0,0 +1,64 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/brcm,timer-mfd.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Broadcom's timer MFD
> +
> +maintainers:
> +  - Rafał Miłecki <rafal@milecki.pl>
> +
> +description: |
> +  Broadcom's timer is a block used in multiple SoCs (e.g., BCM4908, BCM63xx,
> +  BCM7038). Despite its name it's not strictly a timer device. It consists of:
> +  timers, watchdog and software reset handler.
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: brcm,timer-mfd

'mfd' is a Linuxism. Name it what Broadcom calls the block. There should 
be at least as many compatibles as there are variations of register 
layouts.

> +      - const: simple-mfd
> +      - const: syscon
> +
> +  reg:
> +    maxItems: 1
> +
> +  ranges: true
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 1
> +
> +patternProperties:
> +  '^watchdog@[a-f0-9]+$':
> +    $ref: ../watchdog/brcm,bcm7038-wdt.yaml

/schema/watchdog/...

> +
> +additionalProperties: false
> +
> +required:
> +  - reg
> +
> +examples:
> +  - |
> +    timer_mfd: timer-mfd@ff800400 {
> +        compatible = "brcm,timer-mfd", "simple-mfd", "syscon";
> +        reg = <0xff800400 0x4c>;
> +        ranges = <0x0 0xff800400 0x4c>;
> +        #address-cells = <1>;
> +        #size-cells = <1>;
> +
> +        watchdog@28 {
> +            compatible = "brcm,bcm7038-wdt";
> +            reg = <0x28 0x8>;
> +        };

Don't you need a timer node? Make the binding complete.

> +    };
> +
> +    reboot {
> +        compatible = "syscon-reboot";
> +        regmap = <&timer_mfd>;

Make this a child node of the timer.

> +        offset = <0x34>;

Use 'reg'. If "syscon-reboot" doesn't allow that, add it.

> +        mask = <1>;


> +    };
> -- 
> 2.31.1
> 
>