net: phy: Add LED mode driver for Microsemi PHYs.

LED Mode:
Microsemi PHY support 2 LEDs (LED[0] and LED[1]) to display different
status information that can be selected by setting LED mode.

LED Mode parameter (vsc8531, led-0-mode) and (vsc8531, led-1-mode) get
from Device Tree.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/phy/mscc.c b/drivers/net/phy/mscc.c
index e03ead8..650c266 100644
--- a/drivers/net/phy/mscc.c
+++ b/drivers/net/phy/mscc.c
@@ -13,6 +13,7 @@
 #include <linux/phy.h>
 #include <linux/of.h>
 #include <linux/netdevice.h>
+#include <dt-bindings/net/mscc-phy-vsc8531.h>
 
 enum rgmii_rx_clock_delay {
 	RGMII_RX_CLK_DELAY_0_2_NS = 0,
@@ -52,6 +53,11 @@ enum rgmii_rx_clock_delay {
 #define MSCC_PHY_DEV_AUX_CNTL		  28
 #define HP_AUTO_MDIX_X_OVER_IND_MASK	  0x2000
 
+#define MSCC_PHY_LED_MODE_SEL		  29
+#define LED_1_MODE_SEL_MASK		  0x00F0
+#define LED_0_MODE_SEL_MASK		  0x000F
+#define LED_1_MODE_SEL_POS		  4
+
 #define MSCC_EXT_PAGE_ACCESS		  31
 #define MSCC_PHY_PAGE_STANDARD		  0x0000 /* Standard registers */
 #define MSCC_PHY_PAGE_EXTENDED		  0x0001 /* Extended registers */
@@ -99,6 +105,8 @@ enum rgmii_rx_clock_delay {
 
 struct vsc8531_private {
 	int rate_magic;
+	u8 led_0_mode;
+	u8 led_1_mode;
 };
 
 #ifdef CONFIG_OF_MDIO
@@ -123,6 +131,29 @@ static int vsc85xx_phy_page_set(struct phy_device *phydev, u8 page)
 	return rc;
 }
 
+static int vsc85xx_led_cntl_set(struct phy_device *phydev,
+				u8 led_num,
+				u8 mode)
+{
+	int rc;
+	u16 reg_val;
+
+	mutex_lock(&phydev->lock);
+	reg_val = phy_read(phydev, MSCC_PHY_LED_MODE_SEL);
+	if (led_num) {
+		reg_val &= ~LED_1_MODE_SEL_MASK;
+		reg_val |= (((u16)mode << LED_1_MODE_SEL_POS) &
+			    LED_1_MODE_SEL_MASK);
+	} else {
+		reg_val &= ~LED_0_MODE_SEL_MASK;
+		reg_val |= ((u16)mode & LED_0_MODE_SEL_MASK);
+	}
+	rc = phy_write(phydev, MSCC_PHY_LED_MODE_SEL, reg_val);
+	mutex_unlock(&phydev->lock);
+
+	return rc;
+}
+
 static int vsc85xx_mdix_get(struct phy_device *phydev, u8 *mdix)
 {
 	u16 reg_val;
@@ -370,11 +401,41 @@ static int vsc85xx_edge_rate_magic_get(struct phy_device *phydev)
 
 	return -EINVAL;
 }
+
+static int vsc85xx_dt_led_mode_get(struct phy_device *phydev,
+				   char *led,
+				   u8 default_mode)
+{
+	struct device *dev = &phydev->mdio.dev;
+	struct device_node *of_node = dev->of_node;
+	u8 led_mode;
+	int err;
+
+	if (!of_node)
+		return -ENODEV;
+
+	led_mode = default_mode;
+	err = of_property_read_u8(of_node, led, &led_mode);
+	if (!err && (led_mode > 15 || led_mode == 7 || led_mode == 11)) {
+		phydev_err(phydev, "DT %s invalid\n", led);
+		return -EINVAL;
+	}
+
+	return led_mode;
+}
+
 #else
 static int vsc85xx_edge_rate_magic_get(struct phy_device *phydev)
 {
 	return 0;
 }
+
+static int vsc85xx_dt_led_mode_get(struct phy_device *phydev,
+				   char *led,
+				   u8 default_mode)
+{
+	return default_mode;
+}
 #endif /* CONFIG_OF_MDIO */
 
 static int vsc85xx_edge_rate_cntl_set(struct phy_device *phydev, u8 edge_rate)
@@ -499,6 +560,14 @@ static int vsc85xx_config_init(struct phy_device *phydev)
 	if (rc)
 		return rc;
 
+	rc = vsc85xx_led_cntl_set(phydev, 1, vsc8531->led_1_mode);
+	if (rc)
+		return rc;
+
+	rc = vsc85xx_led_cntl_set(phydev, 0, vsc8531->led_0_mode);
+	if (rc)
+		return rc;
+
 	rc = genphy_config_init(phydev);
 
 	return rc;
@@ -555,8 +624,9 @@ static int vsc85xx_read_status(struct phy_device *phydev)
 
 static int vsc85xx_probe(struct phy_device *phydev)
 {
-	int rate_magic;
 	struct vsc8531_private *vsc8531;
+	int rate_magic;
+	int led_mode;
 
 	rate_magic = vsc85xx_edge_rate_magic_get(phydev);
 	if (rate_magic < 0)
@@ -570,6 +640,19 @@ static int vsc85xx_probe(struct phy_device *phydev)
 
 	vsc8531->rate_magic = rate_magic;
 
+	/* LED[0] and LED[1] mode */
+	led_mode = vsc85xx_dt_led_mode_get(phydev, "vsc8531,led-0-mode",
+					   VSC8531_LINK_1000_ACTIVITY);
+	if (led_mode < 0)
+		return led_mode;
+	vsc8531->led_0_mode = led_mode;
+
+	led_mode = vsc85xx_dt_led_mode_get(phydev, "vsc8531,led-1-mode",
+					   VSC8531_LINK_100_ACTIVITY);
+	if (led_mode < 0)
+		return led_mode;
+	vsc8531->led_1_mode = led_mode;
+
 	return 0;
 }