Re: [net-next PATCH 2/2] net: macb: Use mdio child node for MDIO bus if it exists

[Guenter Roeck <linux@roeck-us.net>]

Hi,

while bisecting I noticed the following.

On Fri, Oct 22, 2021 at 12:35:48PM -0400, Sean Anderson wrote:
> This allows explicitly specifying which children are present on the mdio
> bus. Additionally, it allows for non-phy MDIO devices on the bus.
> 
> Signed-off-by: Sean Anderson <sean.anderson@seco.com>
> ---
> 
>  drivers/net/ethernet/cadence/macb_main.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index 029dea2873e3..30a65cac9e87 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -898,6 +898,17 @@ static int macb_mdiobus_register(struct macb *bp)
>  {
>  	struct device_node *child, *np = bp->pdev->dev.of_node;
>  
> +	/* If we have a child named mdio, probe it instead of looking for PHYs
> +	 * directly under the MAC node
> +	 */
> +	child = of_get_child_by_name(np, "mdio");
> +	if (np) {

s/np/child/ 

to avoid network interface failures with messages like

[   12.764530] macb 10090000.ethernet eth0: Could not attach PHY (-19)

I'll send a patch in a minute to fix this up, after bisect is complete
and after testing, to make sure that there is no additional problem.

Guenter

> +		int ret = of_mdiobus_register(bp->mii_bus, child);
> +
> +		of_node_put(child);
> +		return ret;
> +	}
> +
>  	if (of_phy_is_fixed_link(np))
>  		return mdiobus_register(bp->mii_bus);
>  
> -- 
> 2.25.1
>