Merge branch 'phy-sysfs-reciprocal-links'

Florian Fainelli says:

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

This patch series addresses a device topology shortcoming where a program
scanning /sys would not be able to establish a mapping between the network
device and the PHY device.

In the process it turned out that no PHY device documentation existed for
sysfs attributes.

Changes in v2:

- document possible phy_interface values in sysfs-class-net-phydev
====================
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/ABI/testing/sysfs-class-net

@@ -251,3 +251,11 @@ Contact:	netdev@vger.kernel.org
 Description:
 		Indicates the unique physical switch identifier of a switch this
 		port belongs to, as a string.
+
+What:		/sys/class/net/<iface>/phydev
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	netdev@vger.kernel.org
+Description:
+		Symbolic link to the PHY device this network device is attached
+		to.

Documentation/ABI/testing/sysfs-class-net-phydev

+What:		/sys/class/mdio_bus/<bus>/<device>/attached_dev
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	netdev@vger.kernel.org
+Description:
+		Symbolic link to the network device this PHY device is
+		attached to.
+
+What:		/sys/class/mdio_bus/<bus>/<device>/phy_has_fixups
+Date:		February 2014
+KernelVersion:	3.15
+Contact:	netdev@vger.kernel.org
+Description:
+		Boolean value indicating whether the PHY device has
+		any fixups registered against it (phy_register_fixup)
+
+What:		/sys/class/mdio_bus/<bus>/<device>/phy_id
+Date:		November 2012
+KernelVersion:	3.8
+Contact:	netdev@vger.kernel.org
+Description:
+		32-bit hexadecimal value corresponding to the PHY device's OUI,
+		model and revision number.
+
+What:		/sys/class/mdio_bus/<bus>/<device>/phy_interface
+Date:		February 2014
+KernelVersion:	3.15
+Contact:	netdev@vger.kernel.org
+Description:
+		String value indicating the PHY interface, possible
+		values are:.
+		<empty> (not available), mii, gmii, sgmii, tbi, rev-mii,
+		rmii, rgmii, rgmii-id, rgmii-rxid, rgmii-txid, rtbi, smii
+		xgmii, moca, qsgmii, trgmii, 1000base-x, 2500base-x, rxaui,
+		unknown
+

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);