[PATCH v0 08/10] net: phy: Try looking for a phy-handle property to find the OF node

[Jamie Lentin <jm@lentin.co.uk>]

If PHY is registered via. a DSA switch, the MDIO bus the phy is on does
not exist in devicetree, but there may be a reference to the PHY node
on the physical MDIO bus to use.

Signed-off-by: Jamie Lentin <jm@lentin.co.uk>
---
 drivers/net/phy/marvell.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index 280e879..c2ca347 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -302,14 +302,24 @@ static int marvell_config_aneg(struct phy_device *phydev)
  */
 static int marvell_of_reg_init(struct phy_device *phydev)
 {
-	const __be32 *paddr;
+	const __be32 *paddr = NULL;
 	int len, i, saved_page, current_page, page_changed, ret;
+	struct device_node *phy_dn;
+
+	if (phydev->mdio.dev.of_node)
+		paddr = of_get_property(phydev->mdio.dev.of_node,
+					"marvell,reg-init", &len);
+	else if (phydev->attached_dev->dev.of_node) {
+		/* A DSA slave-mii-bus has no OF node, but the PHY might */
+		phy_dn = of_parse_phandle(phydev->attached_dev->dev.of_node,
+					  "phy-handle", 0);
+		if (phy_dn) {
+			paddr = of_get_property(phy_dn,
+						"marvell,reg-init", &len);
+			of_node_put(phy_dn);
+		}
+	}
 
-	if (!phydev->mdio.dev.of_node)
-		return 0;
-
-	paddr = of_get_property(phydev->mdio.dev.of_node,
-				"marvell,reg-init", &len);
 	if (!paddr || len < (4 * sizeof(*paddr)))
 		return 0;
 
-- 
2.8.1