[PATCH net v3 2/2] smsc911x: avoid PHY being resumed when interface is not up

From: Wolfram Sang
Date: Wed Mar 22 2023 - 03:20:16 EST


SMSC911x doesn't need mdiobus suspend/resume, that's why it sets
'mac_managed_pm'. However, setting it needs to be moved from init to
probe, so mdiobus PM functions will really never be called (e.g. when
the interface is not up yet during suspend/resume).

Fixes: 3ce9f2bef755 ("net: smsc911x: Stop and start PHY during suspend and resume")
Suggested-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Changes since v2:
* kept the original error handling when a PHY is not present in
mii_probe() to avoid regressions. Because the patch is simpler now, it
is also easier to backport.

drivers/net/ethernet/smsc/smsc911x.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c
index 67cb5eb9c716..01aac820ac30 100644
--- a/drivers/net/ethernet/smsc/smsc911x.c
+++ b/drivers/net/ethernet/smsc/smsc911x.c
@@ -1037,8 +1037,6 @@ static int smsc911x_mii_probe(struct net_device *dev)
return ret;
}

- /* Indicate that the MAC is responsible for managing PHY PM */
- phydev->mac_managed_pm = true;
phy_attached_info(phydev);

phy_set_max_speed(phydev, SPEED_100);
@@ -1066,6 +1064,7 @@ static int smsc911x_mii_init(struct platform_device *pdev,
struct net_device *dev)
{
struct smsc911x_data *pdata = netdev_priv(dev);
+ struct phy_device *phydev;
int err = -ENXIO;

pdata->mii_bus = mdiobus_alloc();
@@ -1108,6 +1107,10 @@ static int smsc911x_mii_init(struct platform_device *pdev,
goto err_out_free_bus_2;
}

+ phydev = phy_find_first(pdata->mii_bus);
+ if (phydev)
+ phydev->mac_managed_pm = true;
+
return 0;

err_out_free_bus_2:
--
2.30.2