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* [PATCH net] net: phy: Avoid multiple suspends
@ 2020-02-20 23:34 Florian Fainelli
  2020-02-24  4:59 ` David Miller
  0 siblings, 1 reply; 8+ messages in thread
From: Florian Fainelli @ 2020-02-20 23:34 UTC (permalink / raw)
  To: netdev
  Cc: yoshihiro.shimoda.uh, Florian Fainelli, Andrew Lunn,
	Heiner Kallweit, Russell King, David S. Miller, Fugang Duan,
	open list

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

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

Fixes: 803dd9c77ac3 ("net: phy: avoid suspending twice a PHY")
Signed-off-by: Florian Fainelli <>
Heiner, Andrew,

I did consider adding logic that would check for phydev->suspended in
phy_suspend() and phy_resume(), but this was really the only place where
I found it to be problematic.

 drivers/net/phy/phy_device.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 6a5056e0ae77..6131aca79823 100644
--- a/drivers/net/phy/phy_device.c
+++ b/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;
+	return !phydev->suspended;
 static int mdio_bus_phy_suspend(struct device *dev)

^ permalink raw reply related	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2020-03-12  8:27 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-02-20 23:34 [PATCH net] net: phy: Avoid multiple suspends Florian Fainelli
2020-02-24  4:59 ` David Miller
2020-03-10 14:16   ` Geert Uytterhoeven
2020-03-10 16:46     ` Florian Fainelli
2020-03-10 17:34       ` Heiner Kallweit
2020-03-11  9:17       ` Geert Uytterhoeven
2020-03-11 21:22         ` Heiner Kallweit
2020-03-12  8:26           ` Geert Uytterhoeven

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