Add support for configuring AT803x GPIO reset via platform data.
This is necessary, because ath79 is not converted to device tree yet.

Signed-off-by: Felix Fietkau <nbd@nbd.name>

--- a/include/linux/platform_data/phy-at803x.h
+++ b/include/linux/platform_data/phy-at803x.h
@@ -6,6 +6,8 @@ struct at803x_platform_data {
 	int enable_rgmii_tx_delay:1;
 	int enable_rgmii_rx_delay:1;
 	int fixup_rgmii_tx_delay:1;
+	int has_reset_gpio:1;
+	int reset_gpio;
 };
 
 #endif /* _PHY_AT803X_PDATA_H */
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -263,6 +263,7 @@ static int at803x_resume(struct phy_devi
 
 static int at803x_probe(struct phy_device *phydev)
 {
+	struct at803x_platform_data *pdata;
 	struct device *dev = &phydev->mdio.dev;
 	struct at803x_priv *priv;
 	struct gpio_desc *gpiod_reset;
@@ -274,6 +275,12 @@ static int at803x_probe(struct phy_devic
 	if (phydev->drv->phy_id != ATH8030_PHY_ID)
 		goto does_not_require_reset_workaround;
 
+	pdata = dev_get_platdata(dev);
+	if (pdata && pdata->has_reset_gpio) {
+		devm_gpio_request(dev, pdata->reset_gpio, "reset");
+		gpio_direction_output(pdata->reset_gpio, 1);
+	}
+
 	gpiod_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
 	if (IS_ERR(gpiod_reset))
 		return PTR_ERR(gpiod_reset);
@@ -405,15 +412,23 @@ static void at803x_link_change_notify(st
 	 * cannot recover from by software.
 	 */
 	if (phydev->state == PHY_NOLINK) {
-		if (priv->gpiod_reset && !priv->phy_reset) {
+		if ((priv->gpiod_reset || (pdata && pdata->has_reset_gpio)) &&
+		    !priv->phy_reset) {
 			struct at803x_context context;
 
 			at803x_context_save(phydev, &context);
 
-			gpiod_set_value(priv->gpiod_reset, 1);
-			msleep(1);
-			gpiod_set_value(priv->gpiod_reset, 0);
-			msleep(1);
+			if (pdata && pdata->has_reset_gpio) {
+				gpio_set_value_cansleep(pdata->reset_gpio, 0);
+				msleep(1);
+				gpio_set_value_cansleep(pdata->reset_gpio, 1);
+				msleep(1);
+			} else {
+				gpiod_set_value(priv->gpiod_reset, 1);
+				msleep(1);
+				gpiod_set_value(priv->gpiod_reset, 0);
+				msleep(1);
+			}
 
 			at803x_context_restore(phydev, &context);