Re: [PATCH] net: phy: avoid config_init failure on unattached PHY during resume

["Russell King (Oracle)" <linux@armlinux.org.uk>]

On Wed, Sep 10, 2025 at 05:17:03PM +0800, yicongsrfy@163.com wrote:
> Then, because `phydev->interface != PHY_INTERFACE_MODE_SGMII`, it attempts
> to enter `ytphy_rgmii_clk_delay_config` to configure the RGMII tx/rx delay.
> However, since this PHY device is not associated with any GMAC and is not
> connected via an RGMII interface, the function returns `-EOPNOTSUPP`.

It seems the problem is this code:

        /* set rgmii delay mode */
        if (phydev->interface != PHY_INTERFACE_MODE_SGMII) {
                ret = ytphy_rgmii_clk_delay_config(phydev);

which assumes that phydev->interface will be either SGMII or one of
the RGMII modes. This is not the case with a PHY that has been
freshly probed unless phydev->interface is set in the probe function.

I see the probe function decodes the PHYs operating mode and
configures stuff based on that. Maybe, as it only supports RGMII
and SGMII, it should also initialise phydev->interface to the initial
operating condition of the PHY if other code in the driver relies
upon this being set to either SGMII or one of the RGMII types.

-- 
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