[PATCH net-next 3/3] net: phy: dap8211r: add led hardware control support

[Artem Shimko <a.shimko.dev@gmail.com>]

Add support for hardware-controlled leds on the dap8211r phy. The chip
exposes three led that can be programmed to react to link, speed,
duplex, and tx/rx activity.

Implement callbacks for led_hw_is_supported(), led_hw_control_set()
led_hw_control_get().

Signed-off-by: Artem Shimko <a.shimko.dev@gmail.com>
---
 drivers/net/phy/dap8211r.c | 181 +++++++++++++++++++++++++++++++++++++
 1 file changed, 181 insertions(+)

diff --git a/drivers/net/phy/dap8211r.c b/drivers/net/phy/dap8211r.c
index 4eb50c26397f..2e371c231d32 100644
--- a/drivers/net/phy/dap8211r.c
+++ b/drivers/net/phy/dap8211r.c
@@ -12,6 +12,7 @@
  */
 
 #include <linux/bitfield.h>
+#include <linux/bitops.h>
 #include <linux/errno.h>
 #include <linux/ethtool.h>
 #include <linux/kernel.h>
@@ -57,6 +58,33 @@
  */
 #define DAP8211R_DEFAULT_DEL_SEL	0xD
 
+#define DAP8211R_LED_ID_0		0
+#define DAP8211R_LED_ID_1		1
+#define DAP8211R_LED_ID_2		2
+#define DAP8211R_LED_0			0xA00C
+#define DAP8211R_LED_1			0xA00D
+#define DAP8211R_LED_2			0xA00E
+#define DAP8211R_LED_ACT_BLINK		BIT(13)
+#define DAP8211R_LED_FULL_DUPLEX	BIT(12)
+#define DAP8211R_LED_HALF_DUPLEX	BIT(11)
+#define DAP8211R_LED_TX			BIT(10)
+#define DAP8211R_LED_RX			BIT(9)
+#define DAP8211R_LED_LINK_1000		BIT(6)
+#define DAP8211R_LED_LINK_100		BIT(5)
+#define DAP8211R_LED_LINK_10		BIT(4)
+
+#define DAP8211R_LED_LINK		(DAP8211R_LED_LINK_10	| \
+					DAP8211R_LED_LINK_100	| \
+					DAP8211R_LED_LINK_1000)
+
+#define DAP8211R_LED_SUPPORTED_TRG	(BIT(TRIGGER_NETDEV_LINK_10)	| \
+					BIT(TRIGGER_NETDEV_LINK_100)	| \
+					BIT(TRIGGER_NETDEV_LINK_1000)	| \
+					BIT(TRIGGER_NETDEV_TX)		| \
+					BIT(TRIGGER_NETDEV_RX)		| \
+					BIT(TRIGGER_NETDEV_HALF_DUPLEX)	| \
+					BIT(TRIGGER_NETDEV_FULL_DUPLEX))
+
 static const int dap8211r_internal_delay[] = {0, 150, 300, 450, 600, 750, 900,
 					      1050, 1200, 1350, 1500, 1650, 1800,
 					      1950, 2100, 2250};
@@ -142,6 +170,156 @@ static int dap8211r_modify_ext(struct phy_device *phydev, u16 reg, u16 mask, u16
 	return ret;
 }
 
+/**
+ * dap8211r_led_hw_is_supported() - Check if the requested LED rules are supported
+ * @phydev: PHY device structure
+ * @index: LED index
+ * @rules: Bitmask of requested netdev trigger rules
+ *
+ * Validates the requested combination of rules which can be represented in the
+ * hardware register.
+ *
+ * Return: 0 on success, -EINVAL for an invalid LED index,
+ *         or -EOPNOTSUPP if any requested rule is not supported by the PHY
+ */
+static int dap8211r_led_hw_is_supported(struct phy_device *phydev, u8 index, unsigned long rules)
+{
+	switch (index) {
+	case DAP8211R_LED_ID_0:
+		fallthrough;
+	case DAP8211R_LED_ID_1:
+		fallthrough;
+	case DAP8211R_LED_ID_2:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return (rules & ~DAP8211R_LED_SUPPORTED_TRG) ? -EOPNOTSUPP : 0;
+}
+
+/**
+ * dap8211r_led_hw_control_set() - Program the LED control register
+ * @phydev: PHY device structure
+ * @index: LED index
+ * @rules: Bitmask of requested netdev trigger rules
+ *
+ * Translates the requested trigger rules into the corresponding bit
+ * positions of the LED control register and writes the resulting value
+ * to the PHY.
+ *
+ * Note that the ACT_BLINK bit (13) must be set together with TX/RX rules,
+ * otherwise the LED will not blink on traffic if no other rule (such as
+ * link or duplex) is active.
+ *
+ * Return: 0 on success, -EINVAL for an invalid LED index, or a negative error code
+ */
+static int dap8211r_led_hw_control_set(struct phy_device *phydev, u8 index, unsigned long rules)
+{
+	u16 led_mode = 0, led_reg;
+
+	switch (index) {
+	case DAP8211R_LED_ID_0:
+		led_reg = DAP8211R_LED_0;
+		break;
+	case DAP8211R_LED_ID_1:
+		led_reg = DAP8211R_LED_1;
+		break;
+	case DAP8211R_LED_ID_2:
+		led_reg = DAP8211R_LED_2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (test_bit(TRIGGER_NETDEV_LINK, &rules))
+		led_mode |= DAP8211R_LED_LINK;
+
+	if (test_bit(TRIGGER_NETDEV_LINK_10, &rules))
+		led_mode |= DAP8211R_LED_LINK_10;
+
+	if (test_bit(TRIGGER_NETDEV_LINK_100, &rules))
+		led_mode |= DAP8211R_LED_LINK_100;
+
+	if (test_bit(TRIGGER_NETDEV_LINK_1000, &rules))
+		led_mode |= DAP8211R_LED_LINK_1000;
+
+	if (test_bit(TRIGGER_NETDEV_RX, &rules))
+		led_mode |= DAP8211R_LED_RX | DAP8211R_LED_ACT_BLINK;
+
+	if (test_bit(TRIGGER_NETDEV_TX, &rules))
+		led_mode |= DAP8211R_LED_TX | DAP8211R_LED_ACT_BLINK;
+
+	if (test_bit(TRIGGER_NETDEV_HALF_DUPLEX, &rules))
+		led_mode |= DAP8211R_LED_HALF_DUPLEX;
+
+	if (test_bit(TRIGGER_NETDEV_FULL_DUPLEX, &rules))
+		led_mode |= DAP8211R_LED_FULL_DUPLEX;
+
+	if (!led_mode)
+		return -EOPNOTSUPP;
+
+	return dap8211r_write_ext(phydev, led_reg, led_mode);
+}
+
+/**
+ * dap8211r_led_hw_control_get() - Read the current LED configuration
+ * @phydev: PHY device structure
+ * @index: LED index
+ * @rules: Pointer to a bitmask where the current rules will be stored
+ *
+ * Reads the LED control register and translates the hardware bit
+ * positions back into the corresponding netdev trigger rules bitmask.
+ *
+ * Return: 0 on success, -EINVAL for an invalid LED index, or a negative error code
+ */
+static int dap8211r_led_hw_control_get(struct phy_device *phydev, u8 index, unsigned long *rules)
+{
+	u16 led_reg;
+	int led_mode = 0;
+
+	switch (index) {
+	case DAP8211R_LED_ID_0:
+		led_reg = DAP8211R_LED_0;
+		break;
+	case DAP8211R_LED_ID_1:
+		led_reg = DAP8211R_LED_1;
+		break;
+	case DAP8211R_LED_ID_2:
+		led_reg = DAP8211R_LED_2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	led_mode = dap8211r_read_ext(phydev, led_reg);
+	if (led_mode < 0)
+		return led_mode;
+
+	if (led_mode & DAP8211R_LED_LINK_10)
+		__set_bit(TRIGGER_NETDEV_LINK_10, rules);
+
+	if (led_mode & DAP8211R_LED_LINK_100)
+		__set_bit(TRIGGER_NETDEV_LINK_100, rules);
+
+	if (led_mode & DAP8211R_LED_LINK_1000)
+		__set_bit(TRIGGER_NETDEV_LINK_1000, rules);
+
+	if (led_mode & DAP8211R_LED_RX)
+		__set_bit(TRIGGER_NETDEV_RX, rules);
+
+	if (led_mode & DAP8211R_LED_TX)
+		__set_bit(TRIGGER_NETDEV_TX, rules);
+
+	if (led_mode & DAP8211R_LED_HALF_DUPLEX)
+		__set_bit(TRIGGER_NETDEV_HALF_DUPLEX, rules);
+
+	if (led_mode & DAP8211R_LED_FULL_DUPLEX)
+		__set_bit(TRIGGER_NETDEV_FULL_DUPLEX, rules);
+
+	return 0;
+}
+
 /**
  * dap8211r_config_init() - Initialize PHY
  * @phydev: PHY device structure
@@ -230,6 +408,9 @@ static struct phy_driver dap8211r_driver[] = {
 		.config_aneg	= genphy_config_aneg,
 		.suspend	= genphy_suspend,
 		.resume		= genphy_resume,
+		.led_hw_is_supported	= dap8211r_led_hw_is_supported,
+		.led_hw_control_set	= dap8211r_led_hw_control_set,
+		.led_hw_control_get	= dap8211r_led_hw_control_get,
 	},
 };
 module_phy_driver(dap8211r_driver);
-- 
2.43.0