Hi Geert,
Thanks for your suggestion.
On 2024-03-11 10:32:35 +0100, Geert Uytterhoeven wrote:
> Hi Niklas,
>
> On Sat, Mar 9, 2024 at 4:55 PM Niklas Söderlund
> <niklas.soderlund+renesas@xxxxxxxxxxxx> wrote:
> > The driver used the OF node of the device itself when registering the
> > MDIO bus. While this works it creates a problem, it forces any MDIO bus
> > properties to also be set on the devices OF node. This mixes the
> > properties of two distinctly different things and is confusing.
> >
> > This change adds support for an optional mdio node to be defined as a
> > child to the device OF node. The child node can then be used to describe
> > MDIO bus properties that the MDIO core can act on when registering the
> > bus.
> >
> > If no mdio child node is found the driver fallback to the old behavior
> > and register the MDIO bus using the device OF node. This change is
> > backward compatible with old bindings in use.
> >
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
>
> Thanks for your patch!
>
> > --- a/drivers/net/ethernet/renesas/ravb_main.c
> > +++ b/drivers/net/ethernet/renesas/ravb_main.c
> > @@ -2582,8 +2583,20 @@ static int ravb_mdio_init(struct ravb_private *priv)
> > snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
> > pdev->name, pdev->id);
> >
> > - /* Register MDIO bus */
> > - error = of_mdiobus_register(priv->mii_bus, dev->of_node);
> > + /* Register MDIO bus
> > + *
> > + * Look for a mdio child node, if it exist use it when registering the
> > + * MDIO bus. If no node is found fallback to old behavior and use the
> > + * device OF node. This is used to be able to describe MDIO bus
> > + * properties that are consumed when registering the MDIO bus.
> > + */
> > + mdio_node = of_get_child_by_name(dev->of_node, "mdio");
> > + if (mdio_node) {
> > + error = of_mdiobus_register(priv->mii_bus, mdio_node);
> > + of_node_put(mdio_node);
> > + } else {
> > + error = of_mdiobus_register(priv->mii_bus, dev->of_node);
> > + }
> > if (error)
> > goto out_free_bus;
> >
>
> Perhaps the code should be streamlined for the modern case?
>
> mdio_node = of_get_child_by_name(dev->of_node, "mdio");
> if (!mdio_node) {
> /* backwards compatibility for DT lacking mdio subnode */
> mdio_node = of_node_get(dev->of_node);
> }
>
> error = of_mdiobus_register(priv->mii_bus, mdio_node);
> of_node_put(mdio_node);
>
> When deemed necessary, you can easily replace the backwards
> compatibility handling by error handling later.
This looks much better, will do so as well as s/OF/DT/ in the commit
message for next version.
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds
--
Kind Regards,
Niklas Söderlund
