Re: [PATCH v3 1/9] firmware: arm_scmi: Set fwnode for the generated SCMI platform device

[Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>]

On Thu, 13 Aug 2026 12:32:56 +0100
Sudeep Holla <sudeep.holla@kernel.org> wrote:

> Add a call to device_set_node() in the SCMI probe helper to associate
> generated SCMI platform device with the firmware node of its supplier
> transport device.
> 
> This complements device_set_of_node_from_dev() and ensures that
> firmware node information is propagated correctly for both Device Tree
> and non-DT (e.g. ACPI) based systems.

Hi Sudeep,

When you say 'complement' I'd like to see a little more.  The guts
of both calls includes setting dev->ofnode() adn the extra bit
in device_set_of_node_from_dev() is about ensuring we drop existing
node reference (there isn't one) and increment the reference for what
is the parent of_node.

I may be wrong, but I think that is unnecessary and if I'm wrong I'd
like to see more info here on why it is needed.

Also, if this is commonly needed why doesn't device_set_node() include
that dance?

Unless I fumbled the command, a grep suggests there are no instances
in tree of these both being called near each other.

Jonathan

> 
> Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>
> ---
>  drivers/firmware/arm_scmi/common.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
> index fe8c22cfb9f7..cc7d11c3c1f3 100644
> --- a/drivers/firmware/arm_scmi/common.h
> +++ b/drivers/firmware/arm_scmi/common.h
> @@ -650,6 +650,7 @@ static int __tag##_probe(struct platform_device *pdev)			       \
>  	}								       \
>  									       \
>  	device_set_of_node_from_dev(&spdev->dev, dev);			       \
> +	device_set_node(&spdev->dev, dev_fwnode(dev));			       \
>  									       \
>  	strans.supplier = supplier;					       \
>  	memcpy(&strans.desc, &(__desc), sizeof(strans.desc));		       \
>