drivers: ksz8081: fix reset pin polarity

fabiobaltieri · fabiobaltieri · commit feddb41909ef · 2025-12-09T16:58:30.000Z
The reset pin, like most reset pins, is active low. Fix the driver to
treat it as active low and simplify the pin control logic while at it.
Fix all current boards using the wrong pin definition and add a note for
out of tree users.

Signed-off-by: Fabio Baltieri &lt;fabiobaltieri@google.com&gt;
diff --git a/boards/nxp/frdm_rw612/frdm_rw612_common.dtsi b/boards/nxp/frdm_rw612/frdm_rw612_common.dtsi
@@ -232,7 +232,7 @@ mikrobus_serial: &flexcomm0 {};
 		compatible = "microchip,ksz8081";
 		reg = <2>;
 		status = "okay";
-		reset-gpios = <&hsgpio1 23 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&hsgpio1 23 GPIO_ACTIVE_LOW>;
 		int-gpios = <&hsgpio0 21 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1020_evk/mimxrt1020_evk.dts b/boards/nxp/mimxrt1020_evk/mimxrt1020_evk.dts
@@ -160,7 +160,7 @@ arduino_serial: &lpuart2 {
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio1 4 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio1 22 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1024_evk/mimxrt1024_evk.dts b/boards/nxp/mimxrt1024_evk/mimxrt1024_evk.dts
@@ -152,7 +152,7 @@ arduino_serial: &lpuart2 {
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio1 4 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio1 22 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1050_evk/mimxrt1050_evk.dtsi b/boards/nxp/mimxrt1050_evk/mimxrt1050_evk.dtsi
@@ -200,7 +200,7 @@ zephyr_lcdif: &lcdif {
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio1 9 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio1 9 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio1 10 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1060_evk/mimxrt1060_evk.dtsi b/boards/nxp/mimxrt1060_evk/mimxrt1060_evk.dtsi
@@ -178,7 +178,7 @@ arduino_i2c: &lpi2c1 {
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio1 9 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio1 9 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio1 10 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1064_evk/mimxrt1064_evk.dts b/boards/nxp/mimxrt1064_evk/mimxrt1064_evk.dts
@@ -244,7 +244,7 @@ arduino_serial: &lpuart3 {
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio1 9 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio1 9 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio1 10 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1160_evk/mimxrt1160_evk.dtsi b/boards/nxp/mimxrt1160_evk/mimxrt1160_evk.dtsi
@@ -160,7 +160,7 @@
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio12 12 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio12 12 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio9 11 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/mimxrt1170_evk/mimxrt1170_evk.dtsi b/boards/nxp/mimxrt1170_evk/mimxrt1170_evk.dtsi
@@ -154,7 +154,7 @@ arduino_serial: &lpuart2 {
 		compatible = "microchip,ksz8081";
 		reg = <0>;
 		status = "okay";
-		reset-gpios = <&gpio12 12 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&gpio12 12 GPIO_ACTIVE_LOW>;
 		int-gpios = <&gpio9 11 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/boards/nxp/rd_rw612_bga/rd_rw612_bga_rw612_ethernet.dts b/boards/nxp/rd_rw612_bga/rd_rw612_bga_rw612_ethernet.dts
@@ -33,7 +33,7 @@
 		compatible = "microchip,ksz8081";
 		reg = <2>;
 		status = "okay";
-		reset-gpios = <&hsgpio1 23 GPIO_ACTIVE_HIGH>;
+		reset-gpios = <&hsgpio1 23 GPIO_ACTIVE_LOW>;
 		int-gpios = <&hsgpio0 21 GPIO_ACTIVE_HIGH>;
 		microchip,interface-type = "rmii";
 	};
diff --git a/doc/releases/migration-guide-4.4.rst b/doc/releases/migration-guide-4.4.rst
@@ -60,6 +60,10 @@ Ethernet
   is needed. There you need to specify the fixed link parameters using the ``default-speeds``
   property (:github:`100454`).
 
+* The ``reset-gpios`` property of :dtcompatible:`microchip,ksz8081` has been
+  reworked to be used as active low, you may have to set the pin as
+  ``GPIO_ACTIVE_LOW`` in devicetree (:github:`100751`).
+
 MDIO
 ====
 
diff --git a/drivers/ethernet/phy/phy_microchip_ksz8081.c b/drivers/ethernet/phy/phy_microchip_ksz8081.c
@@ -407,21 +407,19 @@ static int phy_mc_ksz8081_reset_gpio(const struct mc_ksz8081_config *config)
 {
 	int ret;
 
-	if (!config->reset_gpio.port) {
+	if (!gpio_is_ready_dt(&config->reset_gpio)) {
 		return -ENODEV;
 	}
 
-	/* Start reset */
-	ret = gpio_pin_set_dt(&config->reset_gpio, 0);
+	ret = gpio_pin_configure_dt(&config->reset_gpio, GPIO_OUTPUT_ACTIVE);
 	if (ret) {
 		return ret;
 	}
 
 	/* Wait for at least 500 us as specified by datasheet */
 	k_busy_wait(1000);
 
-	/* Reset over */
-	ret = gpio_pin_set_dt(&config->reset_gpio, 1);
+	ret = gpio_pin_set_dt(&config->reset_gpio, 0);
 
 	/* After deasserting reset, must wait at least 100 us to use programming interface */
 	k_busy_wait(200);
@@ -653,21 +651,6 @@ static int ksz8081_init_int_gpios(const struct device *dev)
 #define ksz8081_init_int_gpios(dev) 0
 #endif
 
-#if DT_ANY_INST_HAS_PROP_STATUS_OKAY(reset_gpios)
-static int ksz8081_init_reset_gpios(const struct device *dev)
-{
-	const struct mc_ksz8081_config *config = dev->config;
-
-	if (config->reset_gpio.port == NULL) {
-		return 0;
-	}
-
-	return gpio_pin_configure_dt(&config->reset_gpio, GPIO_OUTPUT_ACTIVE);
-}
-#else
-#define ksz8081_init_reset_gpios(dev) 0
-#endif
-
 static int phy_mc_ksz8081_init(const struct device *dev)
 {
 	const struct mc_ksz8081_config *config = dev->config;
@@ -681,11 +664,6 @@ static int phy_mc_ksz8081_init(const struct device *dev)
 		return ret;
 	}
 
-	ret = ksz8081_init_reset_gpios(dev);
-	if (ret) {
-		return ret;
-	}
-
 	/* Reset PHY */
 	ret = phy_mc_ksz8081_reset(dev);
 	if (ret) {
