[PATCH net-next 2/4] net: phy: as21xxx: fix read_status speed handling

From: Christian Marangi

Date: Thu May 28 2026 - 15:37:18 EST


With further test with 2.5G NIC it was discovered that
phy_resolve_aneg_linkmode is not enough to detect speed higher that 1G
when autoneg is enabled.

Also in the switch case there is a typo where the speed mask is AND with
VEND1_SPEED_STATUS instead of the correct mask VEND1_SPEED_MASK.

Rework the read_status code to always read the speed from the vendor
register and parse the generic bit only for the pause frame.

Fixes: 830877d89edc ("net: phy: Add support for Aeonsemi AS21xxx PHYs")
Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
---
drivers/net/phy/as21xxx.c | 96 +++++++++++++++++++++------------------
1 file changed, 53 insertions(+), 43 deletions(-)

diff --git a/drivers/net/phy/as21xxx.c b/drivers/net/phy/as21xxx.c
index 0db82da8dbdf..97ca37c6929f 100644
--- a/drivers/net/phy/as21xxx.c
+++ b/drivers/net/phy/as21xxx.c
@@ -671,7 +671,7 @@ static int as21xxx_read_link(struct phy_device *phydev, int *bmcr)

static int as21xxx_read_c22_lpa(struct phy_device *phydev)
{
- int lpagb;
+ int lpagb, lpa;

/* MII_STAT1000 are only filled in the mapped C22
* in C45, use that to fill lpagb values and check.
@@ -698,12 +698,20 @@ static int as21xxx_read_c22_lpa(struct phy_device *phydev)
mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising,
lpagb);

+ lpa = phy_read_mmd(phydev, MDIO_MMD_AN,
+ AS21XXX_MDIO_AN_C22 + MII_LPA);
+ if (lpa < 0)
+ return lpa;
+
+ mii_lpa_mod_linkmode_lpa_t(phydev->lp_advertising, lpa);
+
return 0;
}

static int as21xxx_read_status(struct phy_device *phydev)
{
int bmcr, old_link = phydev->link;
+ int speed;
int ret;

ret = as21xxx_read_link(phydev, &bmcr);
@@ -720,58 +728,60 @@ static int as21xxx_read_status(struct phy_device *phydev)
phydev->asym_pause = 0;

if (phydev->autoneg == AUTONEG_ENABLE) {
- ret = genphy_c45_read_lpa(phydev);
- if (ret)
- return ret;
+ if (!phydev->autoneg_complete) {
+ mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising,
+ 0);
+ mii_lpa_mod_linkmode_lpa_t(phydev->lp_advertising, 0);
+ return 0;
+ }

ret = as21xxx_read_c22_lpa(phydev);
if (ret)
return ret;
-
- phy_resolve_aneg_linkmode(phydev);
} else {
- int speed;
-
linkmode_zero(phydev->lp_advertising);
+ }

- speed = phy_read_mmd(phydev, MDIO_MMD_VEND1,
- VEND1_SPEED_STATUS);
- if (speed < 0)
- return speed;
-
- switch (speed & VEND1_SPEED_STATUS) {
- case VEND1_SPEED_10000:
- phydev->speed = SPEED_10000;
- phydev->duplex = DUPLEX_FULL;
- break;
- case VEND1_SPEED_5000:
- phydev->speed = SPEED_5000;
- phydev->duplex = DUPLEX_FULL;
- break;
- case VEND1_SPEED_2500:
- phydev->speed = SPEED_2500;
- phydev->duplex = DUPLEX_FULL;
- break;
- case VEND1_SPEED_1000:
- phydev->speed = SPEED_1000;
- if (bmcr & BMCR_FULLDPLX)
- phydev->duplex = DUPLEX_FULL;
- else
- phydev->duplex = DUPLEX_HALF;
- break;
- case VEND1_SPEED_100:
- phydev->speed = SPEED_100;
+ speed = phy_read_mmd(phydev, MDIO_MMD_VEND1,
+ VEND1_SPEED_STATUS);
+ if (speed < 0)
+ return speed;
+
+ switch (speed & VEND1_SPEED_MASK) {
+ case VEND1_SPEED_10000:
+ phydev->speed = SPEED_10000;
+ phydev->duplex = DUPLEX_FULL;
+ break;
+ case VEND1_SPEED_5000:
+ phydev->speed = SPEED_5000;
+ phydev->duplex = DUPLEX_FULL;
+ break;
+ case VEND1_SPEED_2500:
+ phydev->speed = SPEED_2500;
+ phydev->duplex = DUPLEX_FULL;
+ break;
+ case VEND1_SPEED_1000:
+ phydev->speed = SPEED_1000;
+ if (bmcr & BMCR_FULLDPLX)
phydev->duplex = DUPLEX_FULL;
- break;
- case VEND1_SPEED_10:
- phydev->speed = SPEED_10;
- phydev->duplex = DUPLEX_FULL;
- break;
- default:
- return -EINVAL;
- }
+ else
+ phydev->duplex = DUPLEX_HALF;
+ break;
+ case VEND1_SPEED_100:
+ phydev->speed = SPEED_100;
+ phydev->duplex = DUPLEX_FULL;
+ break;
+ case VEND1_SPEED_10:
+ phydev->speed = SPEED_10;
+ phydev->duplex = DUPLEX_FULL;
+ break;
+ default:
+ return -EINVAL;
}

+ if (phydev->autoneg == AUTONEG_ENABLE)
+ phy_resolve_aneg_pause(phydev);
+
return 0;
}

--
2.53.0