[PATCH net-next v2] net: phy: call phy_init_hw() in phy resume path

[Biju]

From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>

When mac_managed_pm flag is set, mdio_bus_phy_resume() is skipped, so
phy_init_hw(), which performs soft_reset and config_init, is not called
during resume.

This is inconsistent with the non-mac_managed_pm path, where
mdio_bus_phy_resume() calls phy_init_hw() before phy_resume() on every
resume.

To align both paths, move the phy_init_hw() call into phy_resume() itself,
before invoking the driver's resume callback. This ensures PHY soft reset
and re-initialization happen unconditionally, regardless of whether PM is
managed by the MAC or the MDIO bus. As a result, drop the redundant
phy_init_hw() call in mdio_bus_phy_resume().

Additionally, in phy_attach_direct(), replace the separate phy_init_hw()
and phy_resume() calls with a single phy_resume() call, since
phy_init_hw() is now handled inside phy_resume().

Signed-off-by: Ovidiu Panait <ovidiu.panait.rb@xxxxxxxxxxx>
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
v1->v2:
 * Updated commit description.
 * phy_init_hw() is moved from __phy_resume() -> phy_resume() to make it
   lock-free.
 * Dropped redundant phy_init_hw() call from mdio_bus_phy_resume() and
   phy_attach_direct().
---
 drivers/net/phy/phy_device.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 0edff47478c2..4a2b19d39373 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -396,10 +396,6 @@ static __maybe_unused int mdio_bus_phy_resume(struct device *dev)
 	WARN_ON(phydev->state != PHY_HALTED && phydev->state != PHY_READY &&
 		phydev->state != PHY_UP);
 
-	ret = phy_init_hw(phydev);
-	if (ret < 0)
-		return ret;
-
 	ret = phy_resume(phydev);
 	if (ret < 0)
 		return ret;
@@ -1857,16 +1853,14 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
 	if (dev)
 		netif_carrier_off(phydev->attached_dev);
 
-	/* Do initial configuration here, now that
+	/* Do initial configuration inside phy_init_hw(), now that
 	 * we have certain key parameters
 	 * (dev_flags and interface)
 	 */
-	err = phy_init_hw(phydev);
+	err = phy_resume(phydev);
 	if (err)
 		goto error;
 
-	phy_resume(phydev);
-
 	/**
 	 * If the external phy used by current mac interface is managed by
 	 * another mac interface, so we should create a device link between
@@ -2020,6 +2014,10 @@ int phy_resume(struct phy_device *phydev)
 {
 	int ret;
 
+	ret = phy_init_hw(phydev);
+	if (ret)
+		return ret;
+
 	mutex_lock(&phydev->lock);
 	ret = __phy_resume(phydev);
 	mutex_unlock(&phydev->lock);
-- 
2.43.0