stmmac: add phy-handle support to the platform layer

On stmmac driver, PHY specification in device-tree was done using the
non-standard property "snps,phy-addr". Specifying a PHY on a different
MDIO bus that the one within the stmmac controller doesn't seem to be
possible when device-tree is used.

This change adds support for the phy-handle property, as specified in
Documentation/devicetree/bindings/net/ethernet.txt.

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -52,6 +52,7 @@
 #include "stmmac_ptp.h"
 #include "stmmac.h"
 #include <linux/reset.h>
+#include <linux/of_mdio.h>
 
 #define STMMAC_ALIGN(x)	L1_CACHE_ALIGN(x)
 
@@ -816,18 +817,25 @@ static int stmmac_init_phy(struct net_device *dev)
 	priv->speed = 0;
 	priv->oldduplex = -1;
 
-	if (priv->plat->phy_bus_name)
-		snprintf(bus_id, MII_BUS_ID_SIZE, "%s-%x",
-			 priv->plat->phy_bus_name, priv->plat->bus_id);
-	else
-		snprintf(bus_id, MII_BUS_ID_SIZE, "stmmac-%x",
-			 priv->plat->bus_id);
+	if (priv->plat->phy_node) {
+		phydev = of_phy_connect(dev, priv->plat->phy_node,
+					&stmmac_adjust_link, 0, interface);
+	} else {
+		if (priv->plat->phy_bus_name)
+			snprintf(bus_id, MII_BUS_ID_SIZE, "%s-%x",
+				 priv->plat->phy_bus_name, priv->plat->bus_id);
+		else
+			snprintf(bus_id, MII_BUS_ID_SIZE, "stmmac-%x",
+				 priv->plat->bus_id);
 
-	snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT, bus_id,
-		 priv->plat->phy_addr);
-	pr_debug("stmmac_init_phy:  trying to attach to %s\n", phy_id_fmt);
+		snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT, bus_id,
+			 priv->plat->phy_addr);
+		pr_debug("stmmac_init_phy:  trying to attach to %s\n",
+			 phy_id_fmt);
 
-	phydev = phy_connect(dev, phy_id_fmt, &stmmac_adjust_link, interface);
+		phydev = phy_connect(dev, phy_id_fmt, &stmmac_adjust_link,
+				     interface);
+	}
 
 	if (IS_ERR(phydev)) {
 		pr_err("%s: Could not attach to PHY\n", dev->name);

drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c

@@ -28,6 +28,7 @@
 #include <linux/of.h>
 #include <linux/of_net.h>
 #include <linux/of_device.h>
+#include <linux/of_mdio.h>
 
 #include "stmmac.h"
 #include "stmmac_platform.h"
@@ -144,13 +145,16 @@ static int stmmac_probe_config_dt(struct platform_device *pdev,
 	/* Default to phy auto-detection */
 	plat->phy_addr = -1;
 
+	/* If we find a phy-handle property, use it as the PHY */
+	plat->phy_node = of_parse_phandle(np, "phy-handle", 0);
+
 	/* "snps,phy-addr" is not a standard property. Mark it as deprecated
 	 * and warn of its use. Remove this when phy node support is added.
 	 */
 	if (of_property_read_u32(np, "snps,phy-addr", &plat->phy_addr) == 0)
 		dev_warn(&pdev->dev, "snps,phy-addr property is deprecated\n");
 
-	if (plat->phy_bus_name)
+	if (plat->phy_node || plat->phy_bus_name)
 		plat->mdio_bus_data = NULL;
 	else
 		plat->mdio_bus_data =

include/linux/stmmac.h

@@ -99,6 +99,7 @@ struct plat_stmmacenet_data {
 	int phy_addr;
 	int interface;
 	struct stmmac_mdio_bus_data *mdio_bus_data;
+	struct device_node *phy_node;
 	struct stmmac_dma_cfg *dma_cfg;
 	int clk_csr;
 	int has_gmac;