stmmac: fix platform driver unregistering

This patch fixes platform device drivers unregistering and adds proper error
handing on module loading.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/stmmac.h

@@ -127,14 +127,14 @@ static inline int stmmac_register_platform(void)
 }
 static inline void stmmac_unregister_platform(void)
 {
-	platform_driver_register(&stmmac_pltfr_driver);
+	platform_driver_unregister(&stmmac_pltfr_driver);
 }
 #else
 static inline int stmmac_register_platform(void)
 {
 	pr_debug("stmmac: do not register the platf driver\n");
 
-	return -EINVAL;
+	return 0;
 }
 static inline void stmmac_unregister_platform(void)
 {
@@ -162,7 +162,7 @@ static inline int stmmac_register_pci(void)
 {
 	pr_debug("stmmac: do not register the PCI driver\n");
 
-	return -EINVAL;
+	return 0;
 }
 static inline void stmmac_unregister_pci(void)
 {

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -2194,18 +2194,20 @@ int stmmac_restore(struct net_device *ndev)
  */
 static int __init stmmac_init(void)
 {
-	int err_plt = 0;
-	int err_pci = 0;
-
-	err_plt = stmmac_register_platform();
-	err_pci = stmmac_register_pci();
-
-	if ((err_pci) && (err_plt)) {
-		pr_err("stmmac: driver registration failed\n");
-		return -EINVAL;
-	}
+	int ret;
 
+	ret = stmmac_register_platform();
+	if (ret)
+		goto err;
+	ret = stmmac_register_pci();
+	if (ret)
+		goto err_pci;
 	return 0;
+err_pci:
+	stmmac_unregister_platform();
+err:
+	pr_err("stmmac: driver registration failed\n");
+	return ret;
 }
 
 static void __exit stmmac_exit(void)