1 files changed, 42 insertions, 15 deletions

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 675fbd225378..cc1bfd22fb81 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -244,6 +244,46 @@ static bool phy_drv_wol_enabled(struct phy_device *phydev)
 	return wol.wolopts != 0;
 }
 
+static void phy_link_change(struct phy_device *phydev, bool up)
+{
+	struct net_device *netdev = phydev->attached_dev;
+
+	if (up)
+		netif_carrier_on(netdev);
+	else
+		netif_carrier_off(netdev);
+	phydev->adjust_link(netdev);
+	if (phydev->mii_ts && phydev->mii_ts->link_state)
+		phydev->mii_ts->link_state(phydev->mii_ts, phydev);
+}
+
+/**
+ * phy_uses_state_machine - test whether consumer driver uses PAL state machine
+ * @phydev: the target PHY device structure
+ *
+ * Ultimately, this aims to indirectly determine whether the PHY is attached
+ * to a consumer which uses the state machine by calling phy_start() and
+ * phy_stop().
+ *
+ * When the PHY driver consumer uses phylib, it must have previously called
+ * phy_connect_direct() or one of its derivatives, so that phy_prepare_link()
+ * has set up a hook for monitoring state changes.
+ *
+ * When the PHY driver is used by the MAC driver consumer through phylink (the
+ * only other provider of a phy_link_change() method), using the PHY state
+ * machine is not optional.
+ *
+ * Return: true if consumer calls phy_start() and phy_stop(), false otherwise.
+ */
+static bool phy_uses_state_machine(struct phy_device *phydev)
+{
+	if (phydev->phy_link_change == phy_link_change)
+		return phydev->attached_dev && phydev->adjust_link;
+
+	/* phydev->phy_link_change is implicitly phylink_phy_change() */
+	return true;
+}
+
 static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 {
 	struct device_driver *drv = phydev->mdio.dev.driver;
@@ -310,7 +350,7 @@ static __maybe_unused int mdio_bus_phy_suspend(struct device *dev)
 	 * may call phy routines that try to grab the same lock, and that may
 	 * lead to a deadlock.
 	 */
-	if (phydev->attached_dev && phydev->adjust_link)
+	if (phy_uses_state_machine(phydev))
 		phy_stop_machine(phydev);
 
 	if (!mdio_bus_phy_may_suspend(phydev))
@@ -364,7 +404,7 @@ no_resume:
 		}
 	}
 
-	if (phydev->attached_dev && phydev->adjust_link)
+	if (phy_uses_state_machine(phydev))
 		phy_start_machine(phydev);
 
 	return 0;
@@ -1055,19 +1095,6 @@ struct phy_device *phy_find_first(struct mii_bus *bus)
 }
 EXPORT_SYMBOL(phy_find_first);
 
-static void phy_link_change(struct phy_device *phydev, bool up)
-{
-	struct net_device *netdev = phydev->attached_dev;
-
-	if (up)
-		netif_carrier_on(netdev);
-	else
-		netif_carrier_off(netdev);
-	phydev->adjust_link(netdev);
-	if (phydev->mii_ts && phydev->mii_ts->link_state)
-		phydev->mii_ts->link_state(phydev->mii_ts, phydev);
-}
-
 /**
  * phy_prepare_link - prepares the PHY layer to monitor link status
  * @phydev: target phy_device struct