net: core: recursively find netdev by device node

The assumption that a device node is associated either with the
netdev's device, or the parent of that device, does not hold for all
drivers. E.g. Freescale's DPAA has two layers of platform devices
above the netdev. Instead, recursively walk up the tree from the
netdev, allowing any parent to match against the sought after node.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/net-sysfs.c

@@ -1805,12 +1805,12 @@ static struct class net_class __ro_after_init = {
 #ifdef CONFIG_OF_NET
 static int of_dev_node_match(struct device *dev, const void *data)
 {
-	int ret = 0;
-
-	if (dev->parent)
-		ret = dev->parent->of_node == data;
+	for (; dev; dev = dev->parent) {
+		if (dev->of_node == data)
+			return 1;
+	}
 
-	return ret == 0 ? dev->of_node == data : ret;
+	return 0;
 }
 
 /*