Subject: [PATCH AUTOSEL 4.9 21/34] net: phy: Fix not to call phy_resume() if PHY is not attached

From: Sasha Levin <[email-masked]>
Date: Wed, 12 Dec 2018 23:31:47 -0500

From: Yoshihiro Shimoda <[email-masked]>

[ Upstream commit ef1b5bf506b1f0ee3edc98533e1f3ecb105eb46a ]

This patch fixes an issue that mdio_bus_phy_resume() doesn't call
phy_resume() if the PHY is not attached.

Fixes: 803dd9c77ac3 ("net: phy: avoid suspending twice a PHY")
Signed-off-by: Yoshihiro Shimoda <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/phy/phy_device.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index f04be9e8980f..b518fa12fb98 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -80,7 +80,7 @@ static LIST_HEAD(phy_fixup_list);
 static DEFINE_MUTEX(phy_fixup_lock);
 
 #ifdef CONFIG_PM
-static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
+static bool mdio_bus_phy_may_suspend(struct phy_device *phydev, bool suspend)
 {
 	struct device_driver *drv = phydev->mdio.dev.driver;
 	struct phy_driver *phydrv = to_phy_driver(drv);
@@ -92,10 +92,11 @@ static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 	/* PHY not attached? May suspend if the PHY has not already been
 	 * suspended as part of a prior call to phy_disconnect() ->
 	 * phy_detach() -> phy_suspend() because the parent netdev might be the
-	 * MDIO bus driver and clock gated at this point.
+	 * MDIO bus driver and clock gated at this point. Also may resume if
+	 * PHY is not attached.
 	 */
 	if (!netdev)
-		return !phydev->suspended;
+		return suspend ? !phydev->suspended : phydev->suspended;
 
 	/* Don't suspend PHY if the attached netdev parent may wakeup.
 	 * The parent may point to a PCI device, as in tg3 driver.
@@ -125,7 +126,7 @@ static int mdio_bus_phy_suspend(struct device *dev)
 	if (phydev->attached_dev && phydev->adjust_link)
 		phy_stop_machine(phydev);
 
-	if (!mdio_bus_phy_may_suspend(phydev))
+	if (!mdio_bus_phy_may_suspend(phydev, true))
 		return 0;
 
 	return phy_suspend(phydev);
@@ -136,7 +137,7 @@ static int mdio_bus_phy_resume(struct device *dev)
 	struct phy_device *phydev = to_phy_device(dev);
 	int ret;
 
-	if (!mdio_bus_phy_may_suspend(phydev))
+	if (!mdio_bus_phy_may_suspend(phydev, false))
 		goto no_resume;
 
 	ret = phy_resume(phydev);
-- 
2.19.1