Re: [PATCH net-next v3 1/2] net: stmmac: Skip PHY attach if custom PCS is in use

[Maxime Chevallier]

Hi

On 7/29/26 09:42, Zxyan Zhu wrote:
> When a platform provides a custom PCS via the pcs_init callback,
> the MAC's phylink_pcs is already configured. In this case, no
> traditional PHY device is needed.
> 
> Without this, stmmac_init_phy() falls through to the no-phy-node
> path and errors out with "no phy found" when the DT has no
> phy-handle for such interfaces.
> 
> Skip the PHY attach when priv->hw->phylink_pcs is set and
> phy_addr is invalid.
> 
> Fixes: f0ef433fc264 ("net: stmmac: introduce pcs_init/pcs_exit stmmac operations")
> Signed-off-by: Zxyan Zhu <zxyan0222@xxxxxxxxx>

Reviewed-by: Maxime Chevallier <maxime.chevallier@xxxxxxxxxxx>

Maxime

> ---
>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 562d20830b94..575132b9cdbf 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -1347,6 +1347,10 @@ static int stmmac_init_phy(struct net_device *dev)
>  		struct phy_device *phydev;
>  
>  		if (addr < 0) {
> +			/* If a custom PCS is in use, no PHY is needed */
> +			if (priv->hw->phylink_pcs)
> +				return 0;
> +
>  			netdev_err(priv->dev, "no phy found\n");
>  			return -ENODEV;
>  		}