[PATCH] of: mdio: Support fixed links in of_phy_get_and_connect()

[Linus Walleij]

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 <and...@lunn.ch>
Signed-off-by: Linus Walleij <linus.wall...@linaro.org>
---
 drivers/of/of_mdio.c | 17 +++++++++++++----
 1 file 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);
 
-- 
2.17.1