[PATCH net-next v13 01/10] net: phy: aquantia: fix system interface type not updated in forced mode

[Bartosz Golaszewski]

aqr_gen1_read_status() decodes the MDIO_PHYXS_VEND_IF_STATUS register
to determine which SerDes interface the PHY is currently using on its
system side and stores the result in phydev->interface. phylink relies
on this value to configure the MAC.

The autoneg == AUTONEG_DISABLE check is not correct:
MDIO_PHYXS_VEND_IF_STATUS is set by the PHY firmware based on the
negotiated link speed, not based on whether autoneg was used to reach
it. When the link comes up at 1G in forced mode, the register correctly
reads SGMII, but the early return prevents phydev->interface from being
updated. It stays at whatever value it held before (typically 2500BASE-X
from the initial autoneg run), so phylink configures the MAC for the
wrong interface and the link cannot come up.

Remove the autoneg guard so that the system interface type is always
decoded when the link is up.

Cc: stable at vger.kernel.org
Fixes: 110a2432c520 ("net: phy: aquantia: add downshift support")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski at oss.qualcomm.com>
---
 drivers/net/phy/aquantia/aquantia_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/phy/aquantia/aquantia_main.c b/drivers/net/phy/aquantia/aquantia_main.c
index e95d391a6dc233879ae1fb2a97758b3df9600ce5..b720e4e9028cc20823297e8bbd239121aeafa09f 100644
--- a/drivers/net/phy/aquantia/aquantia_main.c
+++ b/drivers/net/phy/aquantia/aquantia_main.c
@@ -544,7 +544,7 @@ static int aqr_gen1_read_status(struct phy_device *phydev)
 	if (ret)
 		return ret;
 
-	if (!phydev->link || phydev->autoneg == AUTONEG_DISABLE)
+	if (!phydev->link)
 		return 0;
 
 	/* The status register is not immediately correct on line side link up.

-- 
2.47.3