Re: [PATCH net-next 3/3] net: stmmac: dwmac-renesas-gbeth: add physical port identification

["Russell King (Oracle)" <linux@armlinux.org.uk>]

On Thu, Dec 04, 2025 at 04:31:22PM +0000, John Madieu wrote:
> +static int renesas_gbeth_get_port_id(struct device *dev)
> +{
> +	int port_id;
> +
> +	if (!device_property_read_u32(dev, "renesas,port-id", &port_id))
> +		return port_id;
> +
> +	port_id = of_alias_get_id(dev_of_node(dev), "ethernet");
> +
> +	return port_id < 0 ? 0 : port_id;
> +}

You fall back to the ethernet alias, which is essentially what
devm_stmmac_probe_config_dt() will assign to plat->bus_id. So, is
there any reason we can't just use plat->bus_id ? Why do we need a
special property?

I really don't like the idea that, with the proposal here, we'll
likely see the stmmac platform glue spawn more platform specific
code. This doesn't scale.

So, the next question: should there be a standard way to describe
these attributes, rather than having lots of vendor specific
properties describing the same information? Should this be part
of the generic binding, iow
Documentation/devicetree/bindings/net/ethernet-controller.yaml ?

-- 
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