net: phylink: use pl->link_interface in phylink_expects_phy()

The phylink_expects_phy() function allows MAC drivers to check if they are
expecting a PHY to attach. The checking condition in phylink_expects_phy()
aims to achieve the same result as the checking condition in
phylink_attach_phy().

However, the checking condition in phylink_expects_phy() uses
pl->link_config.interface, while phylink_attach_phy() uses
pl->link_interface.

Initially, both pl->link_interface and pl->link_config.interface are set
to SGMII, and pl->cfg_link_an_mode is set to MLO_AN_INBAND.

When the interface switches from SGMII to 2500BASE-X,
pl->link_config.interface is updated by phylink_major_config().
At this point, pl->cfg_link_an_mode remains MLO_AN_INBAND, and
pl->link_config.interface is set to 2500BASE-X.
Subsequently, when the STMMAC interface is taken down
administratively and brought back up, it is blocked by
phylink_expects_phy().

Since phylink_expects_phy() and phylink_attach_phy() aim to achieve the
same result, phylink_expects_phy() should check pl->link_interface,
which never changes, instead of pl->link_config.interface, which is
updated by phylink_major_config().

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com>
Link: https://patch.msgid.link/20250227121522.1802832-2-yong.liang.choong@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index a3b186ab38546f5036520f754e2a29079f2324e5..a3f64b6d2d34efdf1f5648c3d31031262c8f07bf 100644 (file)
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -2044,7 +2044,7 @@ bool phylink_expects_phy(struct phylink *pl)
 {
        if (pl->cfg_link_an_mode == MLO_AN_FIXED ||
            (pl->cfg_link_an_mode == MLO_AN_INBAND &&
-            phy_interface_mode_is_8023z(pl->link_config.interface)))
+            phy_interface_mode_is_8023z(pl->link_interface)))
                return false;
        return true;
 }