Re: [PATCH 1/2] dt-bindings: mfd: syscon: introduce no-auto-mmio property for syscons

From: Rob Herring

Date: Thu Oct 30 2025 - 14:16:45 EST


On Wed, Oct 29, 2025 at 08:27:05PM +0300, Dan Carpenter wrote:
> Generally, syscons are created automatically and accessed direclty via
> MMIO however sometimes syscons might only be accessible from the secure
> partition or through SCMI etc. Introduce the no-auto-mmio property to
> tell the operating system that the syscon needs to be handled manually.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/mfd/syscon.yaml | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mfd/syscon.yaml b/Documentation/devicetree/bindings/mfd/syscon.yaml
> index 657c38175fba..a0ad12ae0bee 100644
> --- a/Documentation/devicetree/bindings/mfd/syscon.yaml
> +++ b/Documentation/devicetree/bindings/mfd/syscon.yaml
> @@ -245,6 +245,10 @@ properties:
> resets:
> maxItems: 1
>
> + no-auto-mmio:
> + type: boolean
> + description: Prevents the syscon from being created automatically

"syscon" literally means "have Linux create a regmap for me". If you
don't want that, don't use the "syscon" compatible. Really, I wish we'd
never added it in the first place.

Rob