net: add of_find_eth_device_by_node() function

For DSA support we need to find MAC node by phandle from the switch port
node. So, provide of_find_eth_device_by_node() to solve this task.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.barebox.org/20220413082205.429509-3-o.rempel@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 16 insertions, 0 deletions

diff --git a/net/eth.c b/net/eth.c
index 762c5dfb8a..e9e53341f3 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -506,6 +506,22 @@ void led_trigger_network(enum led_trigger trigger)
 	led_trigger(LED_TRIGGER_NET_TXRX, TRIGGER_FLASH);
 }
 
+struct eth_device *of_find_eth_device_by_node(struct device_node *np)
+{
+	struct eth_device *edev;
+	int ret;
+
+	ret = of_device_ensure_probed(np);
+	if (ret)
+		return NULL;
+
+	list_for_each_entry(edev, &netdev_list, list)
+		if (edev->parent->device_node == np)
+			return edev;
+	return NULL;
+}
+EXPORT_SYMBOL(of_find_eth_device_by_node);
+
 static int of_populate_ethaddr(void)
 {
 	char str[sizeof("xx:xx:xx:xx:xx:xx")];