[PATCH 4.4 18/86] phy: micrel: Ensure interrupts are reenabled on resume

[Greg Kroah-Hartman]

From: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>

[ Upstream commit f5aba91d7f186cba84af966a741a0346de603cd4 ]

At least on ksz8081, when getting back from power down, interrupts are
disabled. ensure they are reenabled if they were previously enabled.

This fixes resuming which is failing on the xplained boards from atmel
since 321beec5047a (net: phy: Use interrupts when available in NOLINK
state)

Fixes: 321beec5047a (net: phy: Use interrupts when available in NOLINK state)
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/phy/micrel.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 98166e144f2dd..48788ef0ac639 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -603,6 +603,21 @@ ksz9021_wr_mmd_phyreg(struct phy_device *phydev, int ptrad, int devnum,
 {
 }
 
+static int kszphy_resume(struct phy_device *phydev)
+{
+	int value;
+
+	mutex_lock(&phydev->lock);
+
+	value = phy_read(phydev, MII_BMCR);
+	phy_write(phydev, MII_BMCR, value & ~BMCR_PDOWN);
+
+	kszphy_config_intr(phydev);
+	mutex_unlock(&phydev->lock);
+
+	return 0;
+}
+
 static int kszphy_probe(struct phy_device *phydev)
 {
 	const struct kszphy_type *type = phydev->drv->driver_data;
@@ -794,7 +809,7 @@ static struct phy_driver ksphy_driver[] = {
 	.ack_interrupt	= kszphy_ack_interrupt,
 	.config_intr	= kszphy_config_intr,
 	.suspend	= genphy_suspend,
-	.resume		= genphy_resume,
+	.resume		= kszphy_resume,
 	.driver		= { .owner = THIS_MODULE,},
 }, {
 	.phy_id		= PHY_ID_KSZ8061,
-- 
2.20.1