[PATCH 1/1] net: phy: realtek: Add support for PHY LEDs on RTL8221B

[PATCH 1/1] net: phy: realtek: Add support for PHY LEDs on RTL8221B

[Chukun Pan]

Realtek RTL8221B Ethernet PHY supports three LED pins which are used to
indicate link status and activity. Add netdev trigger support for them.

Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
---
 drivers/net/phy/realtek/realtek_main.c | 146 +++++++++++++++++++++++++
 1 file changed, 146 insertions(+)

diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
index 023e47ad605b..8a22e18e5c56 100644
--- a/drivers/net/phy/realtek/realtek_main.c
+++ b/drivers/net/phy/realtek/realtek_main.c
@@ -150,6 +150,15 @@
 
 #define RTL8221B_VND2_INSR			0xa4d4
 
+#define RTL822X_VND2_LED(x)			(0xd032 + ((x) * 2))
+#define RTL822X_VND2_LCR_LINK_10		BIT(0)
+#define RTL822X_VND2_LCR_LINK_100		BIT(1)
+#define RTL822X_VND2_LCR_LINK_1000		BIT(2)
+#define RTL822X_VND2_LCR_LINK_2500		BIT(5)
+
+#define RTL822X_VND2_LCR6			0xd040
+#define RTL822X_VND2_LED_ACT(x)			BIT(x)
+
 #define RTL8224_MII_RTCT			0x11
 #define RTL8224_MII_RTCT_ENABLE			BIT(0)
 #define RTL8224_MII_RTCT_PAIR_A			BIT(4)
@@ -1661,6 +1670,135 @@ static int rtl822xb_c45_read_status(struct phy_device *phydev)
 	return 0;
 }
 
+static int rtl822xb_led_brightness_set(struct phy_device *phydev, u8 index,
+				       enum led_brightness value)
+{
+	int ret;
+
+	if (index >= RTL8211x_LED_COUNT)
+		return -EINVAL;
+
+	/* clear HW LED setup */
+	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
+			    RTL822X_VND2_LED(index), 0);
+	if (ret < 0)
+		return ret;
+
+	/* clear HW LED blink */
+	return phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2,
+				  RTL822X_VND2_LCR6,
+				  RTL822X_VND2_LED_ACT(index));
+}
+
+static int rtl822xb_led_hw_is_supported(struct phy_device *phydev, u8 index,
+					unsigned long rules)
+{
+	const unsigned long  act_mask = BIT(TRIGGER_NETDEV_RX) |
+					BIT(TRIGGER_NETDEV_TX);
+
+	const unsigned long link_mask = BIT(TRIGGER_NETDEV_LINK) |
+					BIT(TRIGGER_NETDEV_LINK_10) |
+					BIT(TRIGGER_NETDEV_LINK_100) |
+					BIT(TRIGGER_NETDEV_LINK_1000) |
+					BIT(TRIGGER_NETDEV_LINK_2500);
+
+	if (index >= RTL8211x_LED_COUNT)
+		return -EINVAL;
+
+	/* Filter out any other unsupported triggers. */
+	if (rules & ~(link_mask | act_mask))
+		return -EOPNOTSUPP;
+
+	/* RX and TX are not differentiated, they are not possible
+	 * without combination with a link trigger.
+	 */
+	if ((rules & act_mask) && !(rules & link_mask))
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+
+static int rtl822xb_led_hw_control_get(struct phy_device *phydev, u8 index,
+				       unsigned long *rules)
+{
+	int val;
+
+	if (index >= RTL8211x_LED_COUNT)
+		return -EINVAL;
+
+	val = phy_read_mmd(phydev, MDIO_MMD_VEND2, RTL822X_VND2_LED(index));
+	if (val < 0)
+		return val;
+
+	if (val & RTL822X_VND2_LCR_LINK_10)
+		__set_bit(TRIGGER_NETDEV_LINK_10, rules);
+
+	if (val & RTL822X_VND2_LCR_LINK_100)
+		__set_bit(TRIGGER_NETDEV_LINK_100, rules);
+
+	if (val & RTL822X_VND2_LCR_LINK_1000)
+		__set_bit(TRIGGER_NETDEV_LINK_1000, rules);
+
+	if (val & RTL822X_VND2_LCR_LINK_2500)
+		__set_bit(TRIGGER_NETDEV_LINK_2500, rules);
+
+	if ((val & RTL822X_VND2_LCR_LINK_10) &&
+	    (val & RTL822X_VND2_LCR_LINK_100) &&
+	    (val & RTL822X_VND2_LCR_LINK_1000) &&
+	    (val & RTL822X_VND2_LCR_LINK_2500))
+		__set_bit(TRIGGER_NETDEV_LINK, rules);
+
+	val = phy_read_mmd(phydev, MDIO_MMD_VEND2, RTL822X_VND2_LCR6);
+	if (val < 0)
+		return val;
+
+	if (val & RTL822X_VND2_LED_ACT(index)) {
+		__set_bit(TRIGGER_NETDEV_RX, rules);
+		__set_bit(TRIGGER_NETDEV_TX, rules);
+	}
+
+	return 0;
+}
+
+static int rtl822xb_led_hw_control_set(struct phy_device *phydev, u8 index,
+				       unsigned long rules)
+{
+	u16 val = 0;
+	bool act;
+	int ret;
+
+	if (index >= RTL8211x_LED_COUNT)
+		return -EINVAL;
+
+	if (test_bit(TRIGGER_NETDEV_LINK, &rules) ||
+	    test_bit(TRIGGER_NETDEV_LINK_10, &rules))
+		val |= RTL822X_VND2_LCR_LINK_10;
+
+	if (test_bit(TRIGGER_NETDEV_LINK, &rules) ||
+	    test_bit(TRIGGER_NETDEV_LINK_100, &rules))
+		val |= RTL822X_VND2_LCR_LINK_100;
+
+	if (test_bit(TRIGGER_NETDEV_LINK, &rules) ||
+	    test_bit(TRIGGER_NETDEV_LINK_1000, &rules))
+		val |= RTL822X_VND2_LCR_LINK_1000;
+
+	if (test_bit(TRIGGER_NETDEV_LINK, &rules) ||
+	    test_bit(TRIGGER_NETDEV_LINK_2500, &rules))
+		val |= RTL822X_VND2_LCR_LINK_2500;
+
+	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
+			    RTL822X_VND2_LED(index), val);
+	if (ret < 0)
+		return ret;
+
+	act = test_bit(TRIGGER_NETDEV_RX, &rules) ||
+	      test_bit(TRIGGER_NETDEV_TX, &rules);
+
+	return phy_modify_mmd(phydev, MDIO_MMD_VEND2, RTL822X_VND2_LCR6,
+			      RTL822X_VND2_LED_ACT(index), act ?
+			      RTL822X_VND2_LED_ACT(index) : 0);
+}
+
 static int rtl8224_cable_test_start(struct phy_device *phydev)
 {
 	u32 val;
@@ -2427,6 +2565,10 @@ static struct phy_driver realtek_drvs[] = {
 		.write_page	= rtl821x_write_page,
 		.read_mmd	= rtl822xb_read_mmd,
 		.write_mmd	= rtl822xb_write_mmd,
+		.led_brightness_set = rtl822xb_led_brightness_set,
+		.led_hw_is_supported = rtl822xb_led_hw_is_supported,
+		.led_hw_control_get = rtl822xb_led_hw_control_get,
+		.led_hw_control_set = rtl822xb_led_hw_control_set,
 	}, {
 		.match_phy_device = rtl8221b_vm_cg_match_phy_device,
 		.name		= "RTL8221B-VM-CG 2.5Gbps PHY",
@@ -2446,6 +2588,10 @@ static struct phy_driver realtek_drvs[] = {
 		.write_page	= rtl821x_write_page,
 		.read_mmd	= rtl822xb_read_mmd,
 		.write_mmd	= rtl822xb_write_mmd,
+		.led_brightness_set = rtl822xb_led_brightness_set,
+		.led_hw_is_supported = rtl822xb_led_hw_is_supported,
+		.led_hw_control_get = rtl822xb_led_hw_control_get,
+		.led_hw_control_set = rtl822xb_led_hw_control_set,
 	}, {
 		.match_phy_device = rtl8251b_c45_match_phy_device,
 		.name		= "RTL8251B 5Gbps PHY",
-- 
2.34.1

Re: [PATCH 1/1] net: phy: realtek: Add support for PHY LEDs on RTL8221B

[Nicolai Buchwitz]

On 1.4.2026 12:00, Chukun Pan wrote:
> Realtek RTL8221B Ethernet PHY supports three LED pins which are used to
> indicate link status and activity. Add netdev trigger support for them.
> 
> Signed-off-by: Chukun Pan <amadeus@jmu.edu.cn>
> ---
>  drivers/net/phy/realtek/realtek_main.c | 146 +++++++++++++++++++++++++
>  1 file changed, 146 insertions(+)
> 
> diff --git a/drivers/net/phy/realtek/realtek_main.c 
> b/drivers/net/phy/realtek/realtek_main.c
> index 023e47ad605b..8a22e18e5c56 100644
> --- a/drivers/net/phy/realtek/realtek_main.c
> +++ b/drivers/net/phy/realtek/realtek_main.c
> @@ -150,6 +150,15 @@
> 

[...]

> 
> +static int rtl822xb_led_brightness_set(struct phy_device *phydev, u8 
> index,
> +				       enum led_brightness value)
> +{
> +	int ret;
> +
> +	if (index >= RTL8211x_LED_COUNT)
> +		return -EINVAL;
> +
> +	/* clear HW LED setup */
> +	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
> +			    RTL822X_VND2_LED(index), 0);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* clear HW LED blink */
> +	return phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2,
> +				  RTL822X_VND2_LCR6,
> +				  RTL822X_VND2_LED_ACT(index));
> +}

This clears HW triggers but never actually turns the LED on when
value != LED_OFF. Both paths do the same thing: clear link and
activity config (value isn't used at all).

For LED_OFF that works (no triggers = LED off), but for LED_ON the
LED stays off too since there's no force-on written anywhere.

Compare with bcm_phy_led_brightness_set() which explicitly switches
between BCM_LED_SRC_ON and BCM_LED_SRC_OFF based on value.

If the RTL8221B has a software force-on register, it needs to be
programmed here. If it doesn't, brightness_set should not be
implemented at all. The framework handles its absence.

[...]

Thanks

Nicolai