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

[Jamie Lentin]

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 <j...@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