(4/6) bcm57xx: switch-core.c/switch-robo.c check for port already registered

This patch prevents switch-robo.c from attempting robo_probe on a port
that is already registered.  robo_probe will adjust kernel reference counts
if it detects a switch on the port.  If this patch wasn't applied, the
wrt350n would hang on reboot, waiting for the network driver reference count
to reach zero indefinitely.

Signed-off-by: Ben Pfountz <netprince (at) vt (dot) edu>

SVN-Revision: 11469

package/switch/src/switch-core.c

@@ -404,6 +404,21 @@ switch_vlan_config *switch_parse_vlan(switch_driver *driver, char *buf)
 }
 
 
+int switch_device_registered (char* device) {
+	struct list_head *pos;
+	switch_driver *new;
+
+	list_for_each(pos, &drivers.list) {
+		if (strcmp(list_entry(pos, switch_driver, list)->interface, device) == 0) {
+			printk("There is already a switch registered on the device '%s'\n", device);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+
 int switch_register_driver(switch_driver *driver)
 {
 	struct list_head *pos;
@@ -476,6 +491,7 @@ static void __exit switch_exit(void)
 MODULE_AUTHOR("Felix Fietkau <openwrt@nbd.name>");
 MODULE_LICENSE("GPL");
 
+EXPORT_SYMBOL(switch_device_registered);
 EXPORT_SYMBOL(switch_register_driver);
 EXPORT_SYMBOL(switch_unregister_driver);
 EXPORT_SYMBOL(switch_parse_vlan);

package/switch/src/switch-core.h

@@ -42,6 +42,7 @@ typedef struct {
 } switch_vlan_config;
 
 
+extern int switch_device_registered (char* device);
 extern int switch_register_driver(switch_driver *driver);
 extern void switch_unregister_driver(char *name);
 extern switch_vlan_config *switch_parse_vlan(switch_driver *driver, char *buf);

package/switch/src/switch-robo.c

@@ -528,7 +528,8 @@ static int __init robo_init(void)
 
 	device = strdup("ethX");
 	for (device[3] = '0'; (device[3] <= '3') && notfound; device[3]++) {
-		notfound = robo_probe(device);
+		if (! switch_device_registered (device))
+			notfound = robo_probe(device);
 	}
 	device[3]--;