phy: SMSC device Energy Detect power-down mode

SMSC Ethernet Transceivers (LAN88710, LAN8710, LAN8720, LAN8187,
LAN8700, LAN83C185) provide a mechanism to conserve power when
the device is not connected to an active link partner
(Energy Detect Mode).
So this patch enables the Energy Detect power-down mode
for these Transceivers.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/phy/smsc.c

@@ -25,6 +25,7 @@
 
 #define MII_LAN83C185_ISF 29 /* Interrupt Source Flags */
 #define MII_LAN83C185_IM  30 /* Interrupt Mask */
+#define MII_LAN83C185_CTRL_STATUS 17 /* Mode/Status Register */
 
 #define MII_LAN83C185_ISF_INT1 (1<<1) /* Auto-Negotiation Page Received */
 #define MII_LAN83C185_ISF_INT2 (1<<2) /* Parallel Detection Fault */
@@ -37,8 +38,10 @@
 #define MII_LAN83C185_ISF_INT_ALL (0x0e)
 
 #define MII_LAN83C185_ISF_INT_PHYLIB_EVENTS \
-	(MII_LAN83C185_ISF_INT6 | MII_LAN83C185_ISF_INT4)
+	(MII_LAN83C185_ISF_INT6 | MII_LAN83C185_ISF_INT4 | \
+	 MII_LAN83C185_ISF_INT7)
 
+#define MII_LAN83C185_EDPWRDOWN	(1 << 13) /* EDPWRDOWN */
 
 static int smsc_phy_config_intr(struct phy_device *phydev)
 {
@@ -59,9 +62,23 @@ static int smsc_phy_ack_interrupt(struct phy_device *phydev)
 
 static int smsc_phy_config_init(struct phy_device *phydev)
 {
+	int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
+	if (rc < 0)
+		return rc;
+
+	/* Enable energy detect mode for this SMSC Transceivers */
+	rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
+		       rc | MII_LAN83C185_EDPWRDOWN);
+	if (rc < 0)
+		return rc;
+
 	return smsc_phy_ack_interrupt (phydev);
 }
 
+static int lan911x_config_init(struct phy_device *phydev)
+{
+	return smsc_phy_ack_interrupt(phydev);
+}
 
 static struct phy_driver lan83c185_driver = {
 	.phy_id		= 0x0007c0a0, /* OUI=0x00800f, Model#=0x0a */
@@ -147,7 +164,7 @@ static struct phy_driver lan911x_int_driver = {
 	/* basic functions */
 	.config_aneg	= genphy_config_aneg,
 	.read_status	= genphy_read_status,
-	.config_init	= smsc_phy_config_init,
+	.config_init	= lan911x_config_init,
 
 	/* IRQ related */
 	.ack_interrupt	= smsc_phy_ack_interrupt,