net: usb: asix: refactor asix_read_phy_addr() and handle errors on re…

…turn

[ Upstream commit 7e88b11 ]

Refactor asix_read_phy_addr() to return usable error value directly and
make sure all callers handle this error.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/usb/asix.h

@@ -205,8 +205,7 @@ struct sk_buff *asix_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
 int asix_set_sw_mii(struct usbnet *dev, int in_pm);
 int asix_set_hw_mii(struct usbnet *dev, int in_pm);
 
-int asix_read_phy_addr(struct usbnet *dev, int internal);
-int asix_get_phy_addr(struct usbnet *dev);
+int asix_read_phy_addr(struct usbnet *dev, bool internal);
 
 int asix_sw_reset(struct usbnet *dev, u8 flags, int in_pm);
 

drivers/net/usb/asix_common.c

@@ -288,32 +288,33 @@ int asix_set_hw_mii(struct usbnet *dev, int in_pm)
 	return ret;
 }
 
-int asix_read_phy_addr(struct usbnet *dev, int internal)
+int asix_read_phy_addr(struct usbnet *dev, bool internal)
 {
-	int offset = (internal ? 1 : 0);
+	int ret, offset;
 	u8 buf[2];
-	int ret = asix_read_cmd(dev, AX_CMD_READ_PHY_ID, 0, 0, 2, buf, 0);
 
-	netdev_dbg(dev->net, "asix_get_phy_addr()\n");
+	ret = asix_read_cmd(dev, AX_CMD_READ_PHY_ID, 0, 0, 2, buf, 0);
+	if (ret < 0)
+		goto error;
 
 	if (ret < 2) {
-		netdev_err(dev->net, "Error reading PHYID register: %02x\n", ret);
-		goto out;
+		ret = -EIO;
+		goto error;
 	}
-	netdev_dbg(dev->net, "asix_get_phy_addr() returning 0x%04x\n",
-		   *((__le16 *)buf));
+
+	offset = (internal ? 1 : 0);
 	ret = buf[offset];
 
-out:
+	netdev_dbg(dev->net, "%s PHY address 0x%x\n",
+		   internal ? "internal" : "external", ret);
+
 	return ret;
-}
 
-int asix_get_phy_addr(struct usbnet *dev)
-{
-	/* return the address of the internal phy */
-	return asix_read_phy_addr(dev, 1);
-}
+error:
+	netdev_err(dev->net, "Error reading PHY_ID register: %02x\n", ret);
 
+	return ret;
+}
 
 int asix_sw_reset(struct usbnet *dev, u8 flags, int in_pm)
 {

drivers/net/usb/asix_devices.c

@@ -262,7 +262,10 @@ static int ax88172_bind(struct usbnet *dev, struct usb_interface *intf)
 	dev->mii.mdio_write = asix_mdio_write;
 	dev->mii.phy_id_mask = 0x3f;
 	dev->mii.reg_num_mask = 0x1f;
-	dev->mii.phy_id = asix_get_phy_addr(dev);
+
+	dev->mii.phy_id = asix_read_phy_addr(dev, true);
+	if (dev->mii.phy_id < 0)
+		return dev->mii.phy_id;
 
 	dev->net->netdev_ops = &ax88172_netdev_ops;
 	dev->net->ethtool_ops = &ax88172_ethtool_ops;
@@ -717,7 +720,10 @@ static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf)
 	dev->mii.mdio_write = asix_mdio_write;
 	dev->mii.phy_id_mask = 0x1f;
 	dev->mii.reg_num_mask = 0x1f;
-	dev->mii.phy_id = asix_get_phy_addr(dev);
+
+	dev->mii.phy_id = asix_read_phy_addr(dev, true);
+	if (dev->mii.phy_id < 0)
+		return dev->mii.phy_id;
 
 	dev->net->netdev_ops = &ax88772_netdev_ops;
 	dev->net->ethtool_ops = &ax88772_ethtool_ops;
@@ -1081,7 +1087,10 @@ static int ax88178_bind(struct usbnet *dev, struct usb_interface *intf)
 	dev->mii.phy_id_mask = 0x1f;
 	dev->mii.reg_num_mask = 0xff;
 	dev->mii.supports_gmii = 1;
-	dev->mii.phy_id = asix_get_phy_addr(dev);
+
+	dev->mii.phy_id = asix_read_phy_addr(dev, true);
+	if (dev->mii.phy_id < 0)
+		return dev->mii.phy_id;
 
 	dev->net->netdev_ops = &ax88178_netdev_ops;
 	dev->net->ethtool_ops = &ax88178_ethtool_ops;

drivers/net/usb/ax88172a.c

@@ -220,6 +220,11 @@ static int ax88172a_bind(struct usbnet *dev, struct usb_interface *intf)
 	}
 
 	priv->phy_addr = asix_read_phy_addr(dev, priv->use_embdphy);
+	if (priv->phy_addr < 0) {
+		ret = priv->phy_addr;
+		goto free;
+	}
+
 	ax88172a_reset_phy(dev, priv->use_embdphy);
 
 	/* Asix framing packs multiple eth frames into a 2K usb bulk transfer */