Re: [RFC net-next PATCH v2 1/2] net/fsl: add ACPI support for mdio bus

[Calvin Johnson]

On Sat, Apr 18, 2020 at 12:41:16PM +0100, Russell King - ARM Linux admin wrote:
> On Sat, Apr 18, 2020 at 04:24:31PM +0530, Calvin Johnson wrote:
> > @@ -241,18 +244,81 @@ static int xgmac_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
> >  	return value;
> >  }
> >  
> > +/* Extract the clause 22 phy ID from the compatible string of the form
> > + * ethernet-phy-idAAAA.BBBB
> 
> This comment is incorrect.  What about clause 45 PHYs?

Agree. Will correct it.
May be we need a comment update for of_get_phy_id() also.
https://elixir.bootlin.com/linux/v5.7-rc2/source/drivers/of/of_mdio.c#L28

<snip>

> > +	/* All data is now stored in the phy struct, so register it */
> > +	rc = phy_device_register(phy);
> > +	if (rc) {
> > +		phy_device_free(phy);
> > +		fwnode_handle_put(child);
> > +		return rc;
> > +	}
> > +
> > +	dev_dbg(&bus->dev, "registered phy at address %i\n", addr);
> > +
> > +	return 0;
> 
> You seem to be duplicating the OF implementation in a private driver,
> converting it to fwnode.  This is not how we develop the Linux kernel.
> We fix subsystem problems by fixing the subsystems, not by throwing
> what should be subsystem code into private drivers.

I've used some part of the of_mdiobus_register_phy(). Looks like some
other network drivers using acpi had also taken similar approach.
Anyway, I'll try to make it generic and move out to subsystem.

Thanks
Calvin