[PATCH 4.19 040/321] net: bcmgenet: reapply manual settings to the PHY

[Greg Kroah-Hartman]

From: Doug Berger <opendmb@xxxxxxxxx>

[ Upstream commit 0686bd9d5e6863f60e4bb1e78e6fe7bb217a0890 ]

The phy_init_hw() function may reset the PHY to a configuration
that does not match manual network settings stored in the phydev
structure. If the phy state machine is polled rather than event
driven this can create a timing hazard where the phy state machine
might alter the settings stored in the phydev structure from the
value read from the BMCR.

This commit follows invocations of phy_init_hw() by the bcmgenet
driver with invocations of the genphy_config_aneg() function to
ensure that the BMCR is written to match the settings held in the
phydev structure. This prevents the risk of manual settings being
accidentally altered.

Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file")
Signed-off-by: Doug Berger <opendmb@xxxxxxxxx>
Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/broadcom/genet/bcmgenet.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 6f7278d2ce4f2..b7d75011cede5 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2619,8 +2619,10 @@ static void bcmgenet_irq_task(struct work_struct *work)
 	spin_unlock_irq(&priv->lock);
 
 	if (status & UMAC_IRQ_PHY_DET_R &&
-	    priv->dev->phydev->autoneg != AUTONEG_ENABLE)
+	    priv->dev->phydev->autoneg != AUTONEG_ENABLE) {
 		phy_init_hw(priv->dev->phydev);
+		genphy_config_aneg(priv->dev->phydev);
+	}
 
 	/* Link UP/DOWN event */
 	if (status & UMAC_IRQ_LINK_EVENT)
@@ -3673,6 +3675,7 @@ static int bcmgenet_resume(struct device *d)
 	phy_init_hw(dev->phydev);
 
 	/* Speed settings must be restored */
+	genphy_config_aneg(dev->phydev);
 	bcmgenet_mii_config(priv->dev, false);
 
 	bcmgenet_set_hw_addr(priv, dev->dev_addr);
-- 
2.20.1