Merge branch 'stmmac-mdio-compat'

Merge branch 'stmmac-mdio-compat'

Phil Reid says:

====================
stmmac: create of compatible mdio bus for stmacc driver

Provide ability to specify a fixed phy in the device tree and
retain the mdio bus if no phy is found. This is needed where
a dsa is connected via a fixed phy and uses the mdio bus for config.
Fixed ptp ref clock calculatins for the stmmac when ptp ref clock
is running at <= 50Mhz. Also add device tree setting to config
ptp clk source on socfpga platforms.

Changes from V5:
- Restore behaviour of unregister mdio bus when no phys found
  if there is no device tree node create the bus.
- Modify condition to allocate mdio_base_data conditional
  on fixed phy presece as well. Maintains existing behaviour
  in conditions where a fixed phy is not present.

Changes from V4:
- Restore #ifdef CONFIG_OF around setting of reset_gpio.
  Member doesn't exist when this isn't defined.

Changes from V3:
- Use if (IS_ENABLED(CONFIG_OF)) instead of #if.
  Reorder some code to reduce if statements.
- of_mdiobus_register already falls back to mdiobus_register
- Tested on system with CONFIG_OF

Changes from V2:
- Formatting, spaces & lines > 80 chars. Using checkpatch
- Drop PTP register debugfs patch.

Changes from V1:
- Fixed mismatch doc / code for ptp_ref_clk dt node.
- Remove unit address from doc example.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 3 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
index bba670c42e37..16c85ccd1762 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
@@ -29,7 +29,7 @@
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_gpio.h>
-
+#include <linux/of_mdio.h>
 #include <asm/io.h>
 
 #include "stmmac.h"
@@ -200,10 +200,29 @@ int stmmac_mdio_register(struct net_device *ndev)
 	struct stmmac_priv *priv = netdev_priv(ndev);
 	struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data;
 	int addr, found;
+	struct device_node *mdio_node = NULL;
+	struct device_node *child_node = NULL;
 
 	if (!mdio_bus_data)
 		return 0;
 
+	if (IS_ENABLED(CONFIG_OF)) {
+		for_each_child_of_node(priv->device->of_node, child_node) {
+			if (of_device_is_compatible(child_node,
+						    "snps,dwmac-mdio")) {
+				mdio_node = child_node;
+				break;
+			}
+		}
+
+		if (mdio_node) {
+			netdev_dbg(ndev, "FOUND MDIO subnode\n");
+		} else {
+			netdev_err(ndev, "NO MDIO subnode\n");
+			return 0;
+		}
+	}
+
 	new_bus = mdiobus_alloc();
 	if (new_bus == NULL)
 		return -ENOMEM;
@@ -231,7 +250,8 @@ int stmmac_mdio_register(struct net_device *ndev)
 	new_bus->irq = irqlist;
 	new_bus->phy_mask = mdio_bus_data->phy_mask;
 	new_bus->parent = priv->device;
-	err = mdiobus_register(new_bus);
+
+	err = of_mdiobus_register(new_bus, mdio_node);
 	if (err != 0) {
 		pr_err("%s: Cannot register as MDIO bus\n", new_bus->name);
 		goto bus_register_fail;
@@ -284,7 +304,7 @@ int stmmac_mdio_register(struct net_device *ndev)
 		}
 	}
 
-	if (!found) {
+	if (!found && !mdio_node) {
 		pr_warn("%s: No PHY found\n", ndev->name);
 		mdiobus_unregister(new_bus);
 		mdiobus_free(new_bus);