[PATCH 1/2] net: phy: Add link between phy dev and mac dev

[Xiaolei Wang <xiaolei.wang@windriver.com>]

The external phy used by current mac interface
is managed by another mac interface, so we should
create a device link between phy dev and mac dev.

Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
---
 drivers/net/phy/phy.c | 20 ++++++++++++++++++++
 include/linux/phy.h   |  1 +
 2 files changed, 21 insertions(+)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e741d8aebffe..0ef6b69026c7 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -35,6 +35,7 @@
 #include <net/netlink.h>
 #include <net/genetlink.h>
 #include <net/sock.h>
+#include <linux/of_mdio.h>
 
 #define PHY_STATE_TIME	HZ
 
@@ -1535,3 +1536,22 @@ int phy_ethtool_nway_reset(struct net_device *ndev)
 	return phy_restart_aneg(phydev);
 }
 EXPORT_SYMBOL(phy_ethtool_nway_reset);
+
+/**
+ * The external phy used by current mac interface is managed by
+ * another mac interface, so we should create a device link between
+ * phy dev and mac dev.
+ */
+void phy_mac_link_add(struct device_node *phy_np, struct net_device *ndev)
+{
+	struct phy_device *phy_dev = of_phy_find_device(phy_np);
+	struct device *dev = phy_dev ? &phy_dev->mdio.dev : NULL;
+
+	if (dev && ndev->dev.parent != dev)
+		device_link_add(ndev->dev.parent, dev,
+				DL_FLAG_PM_RUNTIME);
+
+	if (phy_dev)
+		put_device(&phy_dev->mdio.dev);
+}
+EXPORT_SYMBOL(phy_mac_link_add);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index ddf66198f751..11cdfbd81153 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1758,6 +1758,7 @@ int phy_package_join(struct phy_device *phydev, int addr, size_t priv_size);
 void phy_package_leave(struct phy_device *phydev);
 int devm_phy_package_join(struct device *dev, struct phy_device *phydev,
 			  int addr, size_t priv_size);
+void phy_mac_link_add(struct device_node *phy_np, struct net_device *ndev);
 
 #if IS_ENABLED(CONFIG_PHYLIB)
 int __init mdio_bus_init(void);
-- 
2.25.1