net: add micrel KSZ8873MLL switch support

this will allow to detect the link between the switch and the soc
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/micrel.c

@@ -127,6 +127,39 @@ static int ks8051_config_init(struct phy_device *phydev)
 	return 0;
 }
 
+#define KSZ8873MLL_GLOBAL_CONTROL_4	0x06
+#define KSZ8873MLL_GLOBAL_CONTROL_4_DUPLEX	(1 << 6)
+#define KSZ8873MLL_GLOBAL_CONTROL_4_SPEED	(1 << 4)
+int ksz8873mll_read_status(struct phy_device *phydev)
+{
+	int regval;
+
+	/* dummy read */
+	regval = phy_read(phydev, KSZ8873MLL_GLOBAL_CONTROL_4);
+
+	regval = phy_read(phydev, KSZ8873MLL_GLOBAL_CONTROL_4);
+
+	if (regval & KSZ8873MLL_GLOBAL_CONTROL_4_DUPLEX)
+		phydev->duplex = DUPLEX_HALF;
+	else
+		phydev->duplex = DUPLEX_FULL;
+
+	if (regval & KSZ8873MLL_GLOBAL_CONTROL_4_SPEED)
+		phydev->speed = SPEED_10;
+	else
+		phydev->speed = SPEED_100;
+
+	phydev->link = 1;
+	phydev->pause = phydev->asym_pause = 0;
+
+	return 0;
+}
+
+static int ksz8873mll_config_aneg(struct phy_device *phydev)
+{
+	return 0;
+}
+
 static struct phy_driver ksphy_driver[] = {
 {
 	.phy_id		= PHY_ID_KS8737,
@@ -204,6 +237,16 @@ static struct phy_driver ksphy_driver[] = {
 	.ack_interrupt	= kszphy_ack_interrupt,
 	.config_intr	= ksz9021_config_intr,
 	.driver		= { .owner = THIS_MODULE, },
+}, {
+	.phy_id		= PHY_ID_KSZ8873MLL,
+	.phy_id_mask	= 0x00fffff0,
+	.name		= "Micrel KSZ8873MLL Switch",
+	.features	= (SUPPORTED_Pause | SUPPORTED_Asym_Pause),
+	.flags		= PHY_HAS_MAGICANEG,
+	.config_init	= kszphy_config_init,
+	.config_aneg	= ksz8873mll_config_aneg,
+	.read_status	= ksz8873mll_read_status,
+	.driver		= { .owner = THIS_MODULE, },
 } };
 
 static int __init ksphy_init(void)
@@ -232,6 +275,7 @@ static struct mdio_device_id __maybe_unused micrel_tbl[] = {
 	{ PHY_ID_KSZ8021, 0x00ffffff },
 	{ PHY_ID_KSZ8041, 0x00fffff0 },
 	{ PHY_ID_KSZ8051, 0x00fffff0 },
+	{ PHY_ID_KSZ8873MLL, 0x00fffff0 },
 	{ }
 };
 

include/linux/micrel_phy.h

@@ -15,6 +15,7 @@
 
 #define MICREL_PHY_ID_MASK	0x00fffff0
 
+#define PHY_ID_KSZ8873MLL	0x000e7237
 #define PHY_ID_KSZ9021		0x00221610
 #define PHY_ID_KS8737		0x00221720
 #define PHY_ID_KSZ8021		0x00221555