net: phy: Avoid multiple suspends

It is currently possible for a PHY device to be suspended as part of a
network device driver's suspend call while it is still being attached to
that net_device, either via phy_suspend() or implicitly via phy_stop().

Later on, when the MDIO bus controller get suspended, we would attempt
to suspend again the PHY because it is still attached to a network
device.

This is both a waste of time and creates an opportunity for improper
clock/power management bugs to creep in.

Fixes: 803dd9c ("net: phy: avoid suspending twice a PHY")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/phy_device.c

@@ -247,7 +247,7 @@ static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 	 * MDIO bus driver and clock gated at this point.
 	 */
 	if (!netdev)
-		return !phydev->suspended;
+		goto out;
 
 	if (netdev->wol_enabled)
 		return false;
@@ -267,7 +267,8 @@ static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 	if (device_may_wakeup(&netdev->dev))
 		return false;
 
-	return true;
+out:
+	return !phydev->suspended;
 }
 
 static int mdio_bus_phy_suspend(struct device *dev)