[U-Boot] [PATCH] net: designware: remove mdio bus on probe failure

[Simon Goldschmidt]

The designware eth driver registers an mdio bus during probe, but if no
PHY is found, this bus is never removed although probe failes and the
driver is shown as not probed in the dm tree.

This later leads to errors when e.g. the mii or mdio commands try to
use available mdio buses because the mdio bus is still registered but
all corresponding data structures are invalid because probe failed.

Fix this by unregistering the mdio bus on probe failure (just as it is
unregistered in the .remove callback, too).

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>
---

 drivers/net/designware.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/net/designware.c b/drivers/net/designware.c
index 2c5d9560c5..3b6cf5ddb5 100644
--- a/drivers/net/designware.c
+++ b/drivers/net/designware.c
@@ -677,10 +677,10 @@ int designware_eth_probe(struct udevice *dev)
 	struct dw_eth_dev *priv = dev_get_priv(dev);
 	u32 iobase = pdata->iobase;
 	ulong ioaddr;
-	int ret;
+	int ret, err;
 	struct reset_ctl_bulk reset_bulk;
 #ifdef CONFIG_CLK
-	int i, err, clock_nb;
+	int i, clock_nb;
 
 	priv->clock_count = 0;
 	clock_nb = dev_count_phandle_with_args(dev, "clocks", "#clock-cells");
@@ -753,13 +753,23 @@ int designware_eth_probe(struct udevice *dev)
 	priv->interface = pdata->phy_interface;
 	priv->max_speed = pdata->max_speed;
 
-	dw_mdio_init(dev->name, dev);
+	ret = dw_mdio_init(dev->name, dev);
+	if (ret) {
+		err = ret;
+		goto mdio_err;
+	}
 	priv->bus = miiphy_get_dev_by_name(dev->name);
 
 	ret = dw_phy_init(priv, dev);
 	debug("%s, ret=%d\n", __func__, ret);
+	if (!ret)
+		return 0;
 
-	return ret;
+	/* continue here for cleanup if no PHY found */
+	err = ret;
+	mdio_unregister(priv->bus);
+	mdio_free(priv->bus);
+mdio_err:
 
 #ifdef CONFIG_CLK
 clk_err:
@@ -767,8 +777,8 @@ clk_err:
 	if (ret)
 		pr_err("failed to disable all clocks\n");
 
-	return err;
 #endif
+	return err;
 }
 
 static int designware_eth_remove(struct udevice *dev)
-- 
2.20.1