Re: [PATCH v4 1/2] dt-bindings: i2c-mux: Add property for settle time

From: Rob Herring
Date: Fri Nov 12 2021 - 14:51:26 EST


On Wed, Nov 03, 2021 at 10:18:38AM +0100, Horatiu Vultur wrote:
> Some HW requires some time for the signals to settle after the muxing is
> changed. Allow this time to be specified in device tree.
>
> Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/i2c/i2c-mux.yaml | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> index 24cac36037f5..4c81e56d02f7 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> @@ -19,6 +19,11 @@ description: |+
> populating the i2c child busses. If an 'i2c-mux' subnode is present, only
> subnodes of this will be considered as i2c child busses.
>
> + Optional properties may not be supported by all drivers. However, if a driver
> + wants to support one of the below features, it should adopt these bindings.

What drivers? Bindings are independent. I don't think you need the
comment, but this should be a separate change with an explanation along
the lines of what we discussed.

> +
> +select: false
> +
> properties:
> $nodename:
> pattern: '^(i2c-?)?mux'
> @@ -29,6 +34,11 @@ properties:
> '#size-cells':
> const: 0
>
> + settle-time-us:
> + default: 0
> + description:
> + The time required for the signals to settle.
> +
> patternProperties:
> '^i2c@[0-9a-f]+$':
> $ref: /schemas/i2c/i2c-controller.yaml
> @@ -41,6 +51,10 @@ patternProperties:
>
> additionalProperties: true
>
> +required:
> + - '#address-cells'
> + - '#size-cells'
> +

This too is a separate change.

> examples:
> - |
> /*
> --
> 2.33.0
>
>