Re: [PATCH v6 11/11] of: mdio: Prevent of_mdiobus_register from scanning mdio-mux nodes

From: Andrew Lunn
Date: Wed Sep 27 2017 - 10:12:27 EST


On Wed, Sep 27, 2017 at 09:34:14AM +0200, Corentin Labbe wrote:
> Each child node of an MDIO node is scanned as a PHY when calling
> of_mdiobus_register() givint the following result:
> [ 18.175379] mdio_bus stmmac-0: /soc/ethernet@1c30000/mdio/mdio-mux has invalid PHY address
> [ 18.175408] mdio_bus stmmac-0: scan phy mdio-mux at address 0
> [ 18.175450] mdio_bus stmmac-0: scan phy mdio-mux at address 1
> [...]
> [ 18.176420] mdio_bus stmmac-0: scan phy mdio-mux at address 30
> [ 18.176452] mdio_bus stmmac-0: scan phy mdio-mux at address 31
>
> Since mdio-mux nodes are not PHY, this patch a way to to not scan
> them.

Hi Corentin

I still don't like this, but ...

>
> Signed-off-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
> ---
> drivers/of/of_mdio.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
> index d94dd8b77abd..d90ddb0d90f2 100644
> --- a/drivers/of/of_mdio.c
> +++ b/drivers/of/of_mdio.c
> @@ -190,6 +190,10 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
> struct device_node *child;
> bool scanphys = false;
> int addr, rc;
> + static const struct of_device_id do_not_scan[] = {
> + { .compatible = "mdio-mux" },
> + {}
> + };

Please rename this to some less generic. What i don't want is other
compatible strings added here. We want to make the exception for
muxes, but nothing else. So something like compatible_muxes?

Andrew