of: mdio: Support fixed links in of_phy_get_and_connect()

By a simple extension of of_phy_get_and_connect() drivers
that have a fixed link on e.g. RGMII can support also
fixed links, so in addition to:

ethernet-port {
	phy-mode = "rgmii";
	phy-handle = <&foo>;
};

This setup with a fixed-link node and no phy-handle will
now also work just fine:

ethernet-port {
	phy-mode = "rgmii";
	fixed-link {
		speed = <1000>;
		full-duplex;
		pause;
	};
};

This is very helpful for connecting random ethernet ports
to e.g. DSA switches that typically reside on fixed links.

The phy-mode is still there as the fixes link in this case
is still an RGMII link.

Tested on the Cortina Gemini driver with the Vitesse DSA
router chip on a fixed 1Gbit link.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 4 deletions

diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index d963baf8e53a..e92391d6d1bd 100644
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -367,14 +367,23 @@ struct phy_device *of_phy_get_and_connect(struct net_device *dev,
         phy_interface_t iface;
         struct device_node *phy_np;
         struct phy_device *phy;
+        int ret;
 
         iface = of_get_phy_mode(np);
         if (iface < 0)
                 return NULL;
-
-        phy_np = of_parse_phandle(np, "phy-handle", 0);
-        if (!phy_np)
-                return NULL;
+        if (of_phy_is_fixed_link(np)) {
+                ret = of_phy_register_fixed_link(np);
+                if (ret < 0) {
+                        netdev_err(dev, "broken fixed-link specification\n");
+                        return NULL;
+                }
+                phy_np = of_node_get(np);
+        } else {
+                phy_np = of_parse_phandle(np, "phy-handle", 0);
+                if (!phy_np)
+                        return NULL;
+        }
 
         phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);