drivers: ethernet: adin2111: add support for hardware reset

Add support for hardware reset via GPIO in the ADIN2111 PHY driver.

The reset pin is configured via device tree using the reset-gpios
property.

Signed-off-by: Tim Pambor <[email protected]>

Author: tpambor

drivers/ethernet/phy/phy_adin2111.c

@@ -10,6 +10,7 @@
 #include <stdbool.h>
 #include <zephyr/kernel.h>
 #include <zephyr/device.h>
+#include <zephyr/drivers/gpio.h>
 #include <zephyr/drivers/mdio.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/net/mdio.h>
@@ -20,6 +21,14 @@
 
 LOG_MODULE_REGISTER(phy_adin, CONFIG_PHY_LOG_LEVEL);
 
+/*
+ * Only compile in support for the optional GPIOs if at least one enabled device tree node
+ * has them.
+ */
+#define ADIN2111_RST_GPIO_SUPPORT                                                                  \
+	(DT_ANY_COMPAT_HAS_PROP_STATUS_OKAY(adi_adin1100_phy, reset_gpios) ||                      \
+	 DT_ANY_COMPAT_HAS_PROP_STATUS_OKAY(adi_adin2111_phy, reset_gpios))
+
 /* PHYs out of reset check retry delay */
 #define ADIN2111_PHY_AWAIT_DELAY_POLL_US			15U
 /*
@@ -36,6 +45,7 @@ LOG_MODULE_REGISTER(phy_adin, CONFIG_PHY_LOG_LEVEL);
 
 /* Software reset, CLK_25 disabled time*/
 #define ADIN1100_PHY_SFT_RESET_MS				25U
+#define ADIN1100_PHY_HRD_RESET_MS				70U
 
 /* PHYs autonegotiation complete timeout */
 #define ADIN2111_AN_COMPLETE_AWAIT_TIMEOUT_MS			3000U
@@ -94,6 +104,9 @@ struct phy_adin2111_config {
 	bool led0_en;
 	bool led1_en;
 	bool tx_24v;
+#if ADIN2111_RST_GPIO_SUPPORT
+	const struct gpio_dt_spec reset_gpio;
+#endif /* ADIN2111_RST_GPIO_SUPPORT */
 	bool mii;
 };
 
@@ -352,6 +365,31 @@ static int phy_adin2111_reset(const struct device *dev)
 {
 	int ret;
 
+#if ADIN2111_RST_GPIO_SUPPORT
+	const struct phy_adin2111_config *config = dev->config;
+
+	if (!config->reset_gpio.port) {
+		goto skip_reset_gpio;
+	}
+
+	/* Assert reset (min. reset pulse width 10us) */
+	ret = gpio_pin_set_dt(&config->reset_gpio, 1);
+	if (ret < 0) {
+		return ret;
+	}
+	k_busy_wait(50);
+
+	/* Deassert reset */
+	ret = gpio_pin_set_dt(&config->reset_gpio, 0);
+	if (ret < 0) {
+		return ret;
+	}
+
+	k_msleep(ADIN1100_PHY_HRD_RESET_MS);
+
+	return 0;
+skip_reset_gpio:
+#endif /* ADIN2111_RST_GPIO_SUPPORT */
 	ret = phy_adin2111_c22_write(dev, MII_BMCR, MII_BMCR_RESET);
 	if (ret < 0) {
 		return ret;
@@ -439,6 +477,15 @@ static int phy_adin2111_init(const struct device *dev)
 	data->state.is_up = false;
 	data->state.speed = LINK_FULL_10BASE;
 
+#if ADIN2111_RST_GPIO_SUPPORT
+	if (cfg->reset_gpio.port) {
+		ret = gpio_pin_configure_dt(&cfg->reset_gpio, GPIO_OUTPUT_INACTIVE);
+		if (ret < 0) {
+			return ret;
+		}
+	}
+#endif /* ADIN2111_RST_GPIO_SUPPORT */
+
 	/*
 	 * For adin1100 and further mii stuff,
 	 * reset may not be performed from the mac layer, doing a clean reset here.
@@ -617,13 +664,21 @@ static DEVICE_API(ethphy, phy_adin2111_api) = {
 	.write = phy_adin2111_reg_write,
 };
 
+#if ADIN2111_RST_GPIO_SUPPORT
+#define RESET_GPIO(n) \
+		.reset_gpio = GPIO_DT_SPEC_INST_GET_OR(n, reset_gpios, {0}),
+#else
+#define RESET_GPIO(n)
+#endif /* reset gpio */
+
 #define ADIN2111_PHY_INITIALIZE(n, model)						\
 	static const struct phy_adin2111_config phy_adin##model##_config_##n = {	\
 		.mdio = DEVICE_DT_GET(DT_INST_BUS(n)),					\
 		.phy_addr = DT_INST_REG_ADDR(n),					\
 		.led0_en = DT_INST_PROP(n, led0_en),					\
 		.led1_en = DT_INST_PROP(n, led1_en),					\
 		.tx_24v = !(DT_INST_PROP(n, disable_tx_mode_24v)),			\
+		RESET_GPIO(n)								\
 		IF_ENABLED(DT_HAS_COMPAT_STATUS_OKAY(adi_adin1100_phy),			\
 		(.mii = 1))								\
 	};										\

dts/bindings/ethernet/phy/adi,adin2111-phy.yaml

@@ -13,6 +13,9 @@ properties:
   reg:
     required: true
     description: 5-bit physical/port address (PRTAD).
+  reset-gpios:
+    type: phandle-array
+    description: GPIO connected to PHY reset signal pin. Reset is active low.
   led0-en:
     type: boolean
     description: Enable LED 0.