[PATCH 4.19 076/639] net: phy: Fix not to call phy_resume() if PHY is not attached

From: Greg Kroah-Hartman
Date: Fri Jan 24 2020 - 06:02:27 EST


From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>

[ 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 <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 43c4f358eeb8a..9c7e51443f6b6 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -76,7 +76,7 @@ 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);
@@ -88,10 +88,11 @@ 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;

if (netdev->wol_enabled)
return false;
@@ -126,7 +127,7 @@ 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);
@@ -137,7 +138,7 @@ 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);
--
2.20.1