SMC911X: Add chip auto detection

Refactor the smc911x driver to allow for detecting when the chip is missing.
I.e. the detect_chip() function is called earlier and will abort gracefully
when the Chip ID read returns all 1's.

Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Dirk Behme <dirk.behme@googlemail.com>
Acked-by: Ben Warren <biggerbadderben@gmail.com>
diff --git a/drivers/net/smc911x.c b/drivers/net/smc911x.c
index 18a729c..b106ec9 100644
--- a/drivers/net/smc911x.c
+++ b/drivers/net/smc911x.c
@@ -146,10 +146,9 @@
 
 static int smc911x_init(struct eth_device *dev, bd_t * bd)
 {
-	printf(DRIVERNAME ": initializing\n");
+	struct chip_id *id = dev->priv;
 
-	if (smc911x_detect_chip(dev))
-		goto err_out;
+        printf(DRIVERNAME ": detected %s controller\n", id->name);
 
 	smc911x_reset(dev);
 
@@ -162,9 +161,6 @@
 	smc911x_enable(dev);
 
 	return 0;
-
-err_out:
-	return -1;
 }
 
 static int smc911x_send(struct eth_device *dev,
@@ -268,6 +264,12 @@
 	dev->recv = smc911x_rx;
 	sprintf(dev->name, "%s-%hu", DRIVERNAME, dev_num);
 
+	/* Try to detect chip. Will fail if not present. */
+	if (smc911x_detect_chip(dev)) {
+		free(dev);
+		return 0;
+	}
+
 	eth_register(dev);
 	return 0;
 }