net: phy: Create sysfs reciprocal links for attached_dev/phydev

There is currently no way for a program scanning /sys to know whether a
network device is attached to a particular PHY device, just like the PHY
device is not pointed back to its attached network device.

Create a symbolic link in the network device's namespace named "phydev"
which points to the PHY device and create a symbolic link in the PHY
device's namespace named "attached_dev" that points back to the network
device. These links are set up during phy_attach_direct() and removed
during phy_detach() for symetry.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 0780e9f9e1677efc6ce4ea47c15a6f77185fdb38..f84414b8f2ee9686dac356dbf37c634993f7f6bf 100644 (file)
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -960,6 +960,15 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
 
        phydev->attached_dev = dev;
        dev->phydev = phydev;
+       err = sysfs_create_link(&phydev->mdio.dev.kobj, &dev->dev.kobj,
+                               "attached_dev");
+       if (err)
+               goto error;
+
+       err = sysfs_create_link(&dev->dev.kobj, &phydev->mdio.dev.kobj,
+                               "phydev");
+       if (err)
+               goto error;
 
        phydev->dev_flags = flags;
 
@@ -1050,6 +1059,8 @@ void phy_detach(struct phy_device *phydev)
        struct mii_bus *bus;
        int i;
 
+       sysfs_remove_link(&dev->dev.kobj, "phydev");
+       sysfs_remove_link(&phydev->mdio.dev.kobj, "attached_dev");
        phydev->attached_dev->phydev = NULL;
        phydev->attached_dev = NULL;
        phy_suspend(phydev);