phylib: Add interrupt source check function to M88E1121R driver

Add did_interrupt() function to check if a PHY port
really caused an interrupt. This is needed in the case
of shared PHY interrupt pin configuration to stop
interrupt event processing for PHY ports which didn't
cause an interrupt.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/marvell.c

@@ -458,6 +458,18 @@ static int marvell_read_status(struct phy_device *phydev)
 	return 0;
 }
 
+static int m88e1121_did_interrupt(struct phy_device *phydev)
+{
+	int imask;
+
+	imask = phy_read(phydev, MII_M1011_IEVENT);
+
+	if (imask & MII_M1011_IMASK_INIT)
+		return 1;
+
+	return 0;
+}
+
 static struct phy_driver marvell_drivers[] = {
 	{
 		.phy_id = 0x01410c60,
@@ -520,6 +532,7 @@ static struct phy_driver marvell_drivers[] = {
 		.read_status = &marvell_read_status,
 		.ack_interrupt = &marvell_ack_interrupt,
 		.config_intr = &marvell_config_intr,
+		.did_interrupt = &m88e1121_did_interrupt,
 		.driver = { .owner = THIS_MODULE },
 	},
 	{