sfp: add sfp-bus to bridge between network devices and sfp cages

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 663 insertions, 0 deletions

diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index c43e5b99fda4..4c16a10f420e 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -38,6 +38,9 @@ obj-$(CONFIG_MDIO_SUN4I)	+= mdio-sun4i.o
 obj-$(CONFIG_MDIO_THUNDER)	+= mdio-thunder.o
 obj-$(CONFIG_MDIO_XGENE)	+= mdio-xgene.o
 
+sfp-obj-$(CONFIG_SFP)		+= sfp-bus.o
+obj-y				+= $(sfp-obj-y) $(sfp-obj-m)
+
 obj-$(CONFIG_AMD_PHY)		+= amd.o
 obj-$(CONFIG_AQUANTIA_PHY)	+= aquantia.o
 obj-$(CONFIG_AT803X_PHY)	+= at803x.o
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index af61d7d400af..02082f4a8a95 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -21,6 +21,7 @@
 #include <linux/spinlock.h>
 #include <linux/workqueue.h>
 
+#include "sfp.h"
 #include "swphy.h"
 
 #define SUPPORTED_INTERFACES \
@@ -32,6 +33,7 @@
 
 enum {
 	PHYLINK_DISABLE_STOPPED,
+	PHYLINK_DISABLE_LINK,
 };
 
 struct phylink {
@@ -54,6 +56,8 @@ struct phylink {
 	struct work_struct resolve;
 
 	bool mac_link_dropped;
+
+	struct sfp_bus *sfp_bus;
 };
 
 static inline void linkmode_zero(unsigned long *dst)
@@ -466,6 +470,24 @@ static void phylink_run_resolve(struct phylink *pl)
 		queue_work(system_power_efficient_wq, &pl->resolve);
 }
 
+static const struct sfp_upstream_ops sfp_phylink_ops;
+
+static int phylink_register_sfp(struct phylink *pl, struct device_node *np)
+{
+	struct device_node *sfp_np;
+
+	sfp_np = of_parse_phandle(np, "sfp", 0);
+	if (!sfp_np)
+		return 0;
+
+	pl->sfp_bus = sfp_register_upstream(sfp_np, pl->netdev, pl,
+					    &sfp_phylink_ops);
+	if (!pl->sfp_bus)
+		return -ENOMEM;
+
+	return 0;
+}
+
 struct phylink *phylink_create(struct net_device *ndev, struct device_node *np,
 	phy_interface_t iface, const struct phylink_mac_ops *ops)
 {
@@ -507,12 +529,21 @@ struct phylink *phylink_create(struct net_device *ndev, struct device_node *np,
 		}
 	}
 
+	ret = phylink_register_sfp(pl, np);
+	if (ret < 0) {
+		kfree(pl);
+		return ERR_PTR(ret);
+	}
+
 	return pl;
 }
 EXPORT_SYMBOL_GPL(phylink_create);
 
 void phylink_destroy(struct phylink *pl)
 {
+	if (pl->sfp_bus)
+		sfp_unregister_upstream(pl->sfp_bus);
+
 	cancel_work_sync(&pl->resolve);
 	kfree(pl);
 }
@@ -706,6 +737,8 @@ void phylink_start(struct phylink *pl)
 	clear_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state);
 	phylink_run_resolve(pl);
 
+	if (pl->sfp_bus)
+		sfp_upstream_start(pl->sfp_bus);
 	if (pl->phydev)
 		phy_start(pl->phydev);
 }
@@ -717,6 +750,8 @@ void phylink_stop(struct phylink *pl)
 
 	if (pl->phydev)
 		phy_stop(pl->phydev);
+	if (pl->sfp_bus)
+		sfp_upstream_stop(pl->sfp_bus);
 
 	set_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state);
 	flush_work(&pl->resolve);
@@ -1166,4 +1201,126 @@ int phylink_mii_ioctl(struct phylink *pl, struct ifreq *ifr, int cmd)
 }
 EXPORT_SYMBOL_GPL(phylink_mii_ioctl);
 
+
+
+static int phylink_sfp_module_insert(void *upstream,
+				     const struct sfp_eeprom_id *id)
+{
+	struct phylink *pl = upstream;
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(support) = { 0, };
+	struct phylink_link_state config;
+	phy_interface_t iface;
+	int mode, ret = 0;
+	bool changed;
+	u8 port;
+
+	sfp_parse_support(pl->sfp_bus, id, support);
+	port = sfp_parse_port(pl->sfp_bus, id, support);
+	iface = sfp_parse_interface(pl->sfp_bus, id);
+
+	WARN_ON(!lockdep_rtnl_is_held());
+
+	switch (iface) {
+	case PHY_INTERFACE_MODE_SGMII:
+		mode = MLO_AN_SGMII;
+		break;
+	case PHY_INTERFACE_MODE_1000BASEX:
+		mode = MLO_AN_8023Z;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	memset(&config, 0, sizeof(config));
+	linkmode_copy(config.advertising, support);
+	config.interface = iface;
+	config.speed = SPEED_UNKNOWN;
+	config.duplex = DUPLEX_UNKNOWN;
+	config.pause = MLO_PAUSE_AN;
+	config.an_enabled = pl->link_config.an_enabled;
+
+	/* Ignore errors if we're expecting a PHY to attach later */
+	ret = phylink_validate(pl, support, &config);
+	if (ret) {
+		netdev_err(pl->netdev, "validation of %s/%s with support %*pb failed: %d\n",
+			   phylink_an_mode_str(mode), phy_modes(config.interface),
+			   __ETHTOOL_LINK_MODE_MASK_NBITS, support, ret);
+		return ret;
+	}
+
+	netdev_dbg(pl->netdev, "requesting link mode %s/%s with support %*pb\n",
+		   phylink_an_mode_str(mode), phy_modes(config.interface),
+		   __ETHTOOL_LINK_MODE_MASK_NBITS, support);
+
+	if (mode == MLO_AN_8023Z && pl->phydev)
+		return -EINVAL;
+
+	changed = !bitmap_equal(pl->supported, support,
+				__ETHTOOL_LINK_MODE_MASK_NBITS);
+	if (changed) {
+		linkmode_copy(pl->supported, support);
+		linkmode_copy(pl->link_config.advertising, config.advertising);
+	}
+
+	if (pl->link_an_mode != mode ||
+	    pl->link_config.interface != config.interface) {
+		pl->link_config.interface = config.interface;
+		pl->link_an_mode = mode;
+
+		changed = true;
+
+		netdev_info(pl->netdev, "switched to %s/%s link mode\n",
+			    phylink_an_mode_str(mode),
+			    phy_modes(config.interface));
+	}
+
+	pl->link_port = port;
+
+	if (changed && !test_bit(PHYLINK_DISABLE_STOPPED,
+				 &pl->phylink_disable_state))
+		phylink_mac_config(pl, &pl->link_config);
+
+	return ret;
+}
+
+static void phylink_sfp_link_down(void *upstream)
+{
+	struct phylink *pl = upstream;
+
+	WARN_ON(!lockdep_rtnl_is_held());
+
+	set_bit(PHYLINK_DISABLE_LINK, &pl->phylink_disable_state);
+	flush_work(&pl->resolve);
+
+	netif_carrier_off(pl->netdev);
+}
+
+static void phylink_sfp_link_up(void *upstream)
+{
+	struct phylink *pl = upstream;
+
+	WARN_ON(!lockdep_rtnl_is_held());
+
+	clear_bit(PHYLINK_DISABLE_LINK, &pl->phylink_disable_state);
+	phylink_run_resolve(pl);
+}
+
+static int phylink_sfp_connect_phy(void *upstream, struct phy_device *phy)
+{
+	return phylink_connect_phy(upstream, phy);
+}
+
+static void phylink_sfp_disconnect_phy(void *upstream)
+{
+	phylink_disconnect_phy(upstream);
+}
+
+static const struct sfp_upstream_ops sfp_phylink_ops = {
+	.module_insert = phylink_sfp_module_insert,
+	.link_up = phylink_sfp_link_up,
+	.link_down = phylink_sfp_link_down,
+	.connect_phy = phylink_sfp_connect_phy,
+	.disconnect_phy = phylink_sfp_disconnect_phy,
+};
+
 MODULE_LICENSE("GPL");
diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
new file mode 100644
index 000000000000..5cb5384697ea
--- /dev/null
+++ b/drivers/net/phy/sfp-bus.c
@@ -0,0 +1,475 @@
+#include <linux/export.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/phylink.h>
+#include <linux/rtnetlink.h>
+#include <linux/slab.h>
+
+#include "sfp.h"
+
+struct sfp_bus {
+	struct kref kref;
+	struct list_head node;
+	struct device_node *device_node;
+
+	const struct sfp_socket_ops *socket_ops;
+	struct device *sfp_dev;
+	struct sfp *sfp;
+
+	const struct sfp_upstream_ops *upstream_ops;
+	void *upstream;
+	struct net_device *netdev;
+	struct phy_device *phydev;
+
+	bool registered;
+	bool started;
+};
+
+
+int sfp_parse_port(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
+		   unsigned long *support)
+{
+	int port;
+
+	/* port is the physical connector, set this from the connector field. */
+	switch (id->base.connector) {
+	case SFP_CONNECTOR_SC:
+	case SFP_CONNECTOR_FIBERJACK:
+	case SFP_CONNECTOR_LC:
+	case SFP_CONNECTOR_MT_RJ:
+	case SFP_CONNECTOR_MU:
+	case SFP_CONNECTOR_OPTICAL_PIGTAIL:
+		if (support)
+			phylink_set(support, FIBRE);
+		port = PORT_FIBRE;
+		break;
+
+	case SFP_CONNECTOR_RJ45:
+		if (support)
+			phylink_set(support, TP);
+		port = PORT_TP;
+		break;
+
+	case SFP_CONNECTOR_UNSPEC:
+		if (id->base.e1000_base_t) {
+			if (support)
+				phylink_set(support, TP);
+			port = PORT_TP;
+			break;
+		}
+		/* fallthrough */
+	case SFP_CONNECTOR_SG: /* guess */
+	case SFP_CONNECTOR_MPO_1X12:
+	case SFP_CONNECTOR_MPO_2X16:
+	case SFP_CONNECTOR_HSSDC_II:
+	case SFP_CONNECTOR_COPPER_PIGTAIL:
+	case SFP_CONNECTOR_NOSEPARATE:
+	case SFP_CONNECTOR_MXC_2X16:
+		port = PORT_OTHER;
+		break;
+	default:
+		dev_warn(bus->sfp_dev, "SFP: unknown connector id 0x%02x\n",
+			 id->base.connector);
+		port = PORT_OTHER;
+		break;
+	}
+
+	return port;
+}
+EXPORT_SYMBOL_GPL(sfp_parse_port);
+
+phy_interface_t sfp_parse_interface(struct sfp_bus *bus,
+				    const struct sfp_eeprom_id *id)
+{
+	phy_interface_t iface;
+
+	/* Setting the serdes link mode is guesswork: there's no field in
+	 * the EEPROM which indicates what mode should be used.
+	 *
+	 * If the module wants 64b66b, then it must be >= 10G.
+	 *
+	 * If it's a gigabit-only fiber module, it probably does not have
+	 * a PHY, so switch to 802.3z negotiation mode. Otherwise, switch
+	 * to SGMII mode (which is required to support non-gigabit speeds).
+	 */
+	switch (id->base.encoding) {
+	case SFP_ENCODING_8472_64B66B:
+		iface = PHY_INTERFACE_MODE_10GKR;
+		break;
+
+	case SFP_ENCODING_8B10B:
+		if (!id->base.e1000_base_t &&
+		    !id->base.e100_base_lx &&
+		    !id->base.e100_base_fx)
+			iface = PHY_INTERFACE_MODE_1000BASEX;
+		else
+			iface = PHY_INTERFACE_MODE_SGMII;
+		break;
+
+	default:
+		iface = PHY_INTERFACE_MODE_NA;
+		dev_err(bus->sfp_dev,
+			"SFP module encoding does not support 8b10b nor 64b66b\n");
+		break;
+	}
+
+	return iface;
+}
+EXPORT_SYMBOL_GPL(sfp_parse_interface);
+
+void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
+		       unsigned long *support)
+{
+	phylink_set(support, Autoneg);
+	phylink_set(support, Pause);
+	phylink_set(support, Asym_Pause);
+
+	/* Set ethtool support from the compliance fields. */
+	if (id->base.e10g_base_sr)
+		phylink_set(support, 10000baseSR_Full);
+	if (id->base.e10g_base_lr)
+		phylink_set(support, 10000baseLR_Full);
+	if (id->base.e10g_base_lrm)
+		phylink_set(support, 10000baseLRM_Full);
+	if (id->base.e10g_base_er)
+		phylink_set(support, 10000baseER_Full);
+	if (id->base.e1000_base_sx ||
+	    id->base.e1000_base_lx ||
+	    id->base.e1000_base_cx)
+		phylink_set(support, 1000baseX_Full);
+	if (id->base.e1000_base_t) {
+		phylink_set(support, 1000baseT_Half);
+		phylink_set(support, 1000baseT_Full);
+	}
+
+	switch (id->base.extended_cc) {
+	case 0x00: /* Unspecified */
+		break;
+	case 0x02: /* 100Gbase-SR4 or 25Gbase-SR */
+		phylink_set(support, 100000baseSR4_Full);
+		phylink_set(support, 25000baseSR_Full);
+		break;
+	case 0x03: /* 100Gbase-LR4 or 25Gbase-LR */
+	case 0x04: /* 100Gbase-ER4 or 25Gbase-ER */
+		phylink_set(support, 100000baseLR4_ER4_Full);
+		break;
+	case 0x0b: /* 100Gbase-CR4 or 25Gbase-CR CA-L */
+	case 0x0c: /* 25Gbase-CR CA-S */
+	case 0x0d: /* 25Gbase-CR CA-N */
+		phylink_set(support, 100000baseCR4_Full);
+		phylink_set(support, 25000baseCR_Full);
+		break;
+	default:
+		dev_warn(bus->sfp_dev,
+			 "Unknown/unsupported extended compliance code: 0x%02x\n",
+			 id->base.extended_cc);
+		break;
+	}
+
+	/* For fibre channel SFP, derive possible BaseX modes */
+	if (id->base.fc_speed_100 ||
+	    id->base.fc_speed_200 ||
+	    id->base.fc_speed_400) {
+		if (id->base.br_nominal >= 31)
+			phylink_set(support, 2500baseX_Full);
+		if (id->base.br_nominal >= 12)
+			phylink_set(support, 1000baseX_Full);
+	}
+
+	switch (id->base.connector) {
+	case SFP_CONNECTOR_SC:
+	case SFP_CONNECTOR_FIBERJACK:
+	case SFP_CONNECTOR_LC:
+	case SFP_CONNECTOR_MT_RJ:
+	case SFP_CONNECTOR_MU:
+	case SFP_CONNECTOR_OPTICAL_PIGTAIL:
+		break;
+
+	case SFP_CONNECTOR_UNSPEC:
+		if (id->base.e1000_base_t)
+			break;
+
+	case SFP_CONNECTOR_SG: /* guess */
+	case SFP_CONNECTOR_MPO_1X12:
+	case SFP_CONNECTOR_MPO_2X16:
+	case SFP_CONNECTOR_HSSDC_II:
+	case SFP_CONNECTOR_COPPER_PIGTAIL:
+	case SFP_CONNECTOR_NOSEPARATE:
+	case SFP_CONNECTOR_MXC_2X16:
+	default:
+		/* a guess at the supported link modes */
+		dev_warn(bus->sfp_dev,
+			 "Guessing link modes, please report...\n");
+		phylink_set(support, 1000baseT_Half);
+		phylink_set(support, 1000baseT_Full);
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(sfp_parse_support);
+
+
+static LIST_HEAD(sfp_buses);
+static DEFINE_MUTEX(sfp_mutex);
+
+static const struct sfp_upstream_ops *sfp_get_upstream_ops(struct sfp_bus *bus)
+{
+	return bus->registered ? bus->upstream_ops : NULL;
+}
+
+static struct sfp_bus *sfp_bus_get(struct device_node *np)
+{
+	struct sfp_bus *sfp, *new, *found = NULL;
+
+	new = kzalloc(sizeof(*new), GFP_KERNEL);
+
+	mutex_lock(&sfp_mutex);
+
+	list_for_each_entry(sfp, &sfp_buses, node) {
+		if (sfp->device_node == np) {
+			kref_get(&sfp->kref);
+			found = sfp;
+			break;
+		}
+	}
+
+	if (!found && new) {
+		kref_init(&new->kref);
+		new->device_node = np;
+		list_add(&new->node, &sfp_buses);
+		found = new;
+		new = NULL;
+	}
+
+	mutex_unlock(&sfp_mutex);
+
+	kfree(new);
+
+	return found;
+}
+
+static void sfp_bus_release(struct kref *kref) __releases(sfp_mutex)
+{
+	struct sfp_bus *bus = container_of(kref, struct sfp_bus, kref);
+
+	list_del(&bus->node);
+	mutex_unlock(&sfp_mutex);
+	kfree(bus);
+}
+
+static void sfp_bus_put(struct sfp_bus *bus)
+{
+	kref_put_mutex(&bus->kref, sfp_bus_release, &sfp_mutex);
+}
+
+static int sfp_register_bus(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = bus->upstream_ops;
+	int ret;
+
+	if (ops) {
+		if (ops->link_down)
+			ops->link_down(bus->upstream);
+		if (ops->connect_phy && bus->phydev) {
+			ret = ops->connect_phy(bus->upstream, bus->phydev);
+			if (ret)
+				return ret;
+		}
+	}
+	if (bus->started)
+		bus->socket_ops->start(bus->sfp);
+	bus->registered = true;
+	return 0;
+}
+
+static void sfp_unregister_bus(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = bus->upstream_ops;
+
+	if (bus->registered) {
+		if (bus->started)
+			bus->socket_ops->stop(bus->sfp);
+		if (bus->phydev && ops && ops->disconnect_phy)
+			ops->disconnect_phy(bus->upstream);
+	}
+	bus->registered = false;
+}
+
+
+int sfp_get_module_info(struct sfp_bus *bus, struct ethtool_modinfo *modinfo)
+{
+	if (!bus->registered)
+		return -ENOIOCTLCMD;
+	return bus->socket_ops->module_info(bus->sfp, modinfo);
+}
+EXPORT_SYMBOL_GPL(sfp_get_module_info);
+
+int sfp_get_module_eeprom(struct sfp_bus *bus, struct ethtool_eeprom *ee,
+	u8 *data)
+{
+	if (!bus->registered)
+		return -ENOIOCTLCMD;
+	return bus->socket_ops->module_eeprom(bus->sfp, ee, data);
+}
+EXPORT_SYMBOL_GPL(sfp_get_module_eeprom);
+
+void sfp_upstream_start(struct sfp_bus *bus)
+{
+	if (bus->registered)
+		bus->socket_ops->start(bus->sfp);
+	bus->started = true;
+}
+EXPORT_SYMBOL_GPL(sfp_upstream_start);
+
+void sfp_upstream_stop(struct sfp_bus *bus)
+{
+	if (bus->registered)
+		bus->socket_ops->stop(bus->sfp);
+	bus->started = false;
+}
+EXPORT_SYMBOL_GPL(sfp_upstream_stop);
+
+struct sfp_bus *sfp_register_upstream(struct device_node *np,
+	struct net_device *ndev, void *upstream,
+	const struct sfp_upstream_ops *ops)
+{
+	struct sfp_bus *bus = sfp_bus_get(np);
+	int ret = 0;
+
+	if (bus) {
+		rtnl_lock();
+		bus->upstream_ops = ops;
+		bus->upstream = upstream;
+		bus->netdev = ndev;
+
+		if (bus->sfp)
+			ret = sfp_register_bus(bus);
+		rtnl_unlock();
+	}
+
+	if (ret) {
+		sfp_bus_put(bus);
+		bus = NULL;
+	}
+
+	return bus;
+}
+EXPORT_SYMBOL_GPL(sfp_register_upstream);
+
+void sfp_unregister_upstream(struct sfp_bus *bus)
+{
+	rtnl_lock();
+	sfp_unregister_bus(bus);
+	bus->upstream = NULL;
+	bus->netdev = NULL;
+	rtnl_unlock();
+
+	sfp_bus_put(bus);
+}
+EXPORT_SYMBOL_GPL(sfp_unregister_upstream);
+
+
+/* Socket driver entry points */
+int sfp_add_phy(struct sfp_bus *bus, struct phy_device *phydev)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+	int ret = 0;
+
+	if (ops && ops->connect_phy)
+		ret = ops->connect_phy(bus->upstream, phydev);
+
+	if (ret == 0)
+		bus->phydev = phydev;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sfp_add_phy);
+
+void sfp_remove_phy(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+
+	if (ops && ops->disconnect_phy)
+		ops->disconnect_phy(bus->upstream);
+	bus->phydev = NULL;
+}
+EXPORT_SYMBOL_GPL(sfp_remove_phy);
+
+
+void sfp_link_up(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+
+	if (ops && ops->link_up)
+		ops->link_up(bus->upstream);
+}
+EXPORT_SYMBOL_GPL(sfp_link_up);
+
+void sfp_link_down(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+
+	if (ops && ops->link_down)
+		ops->link_down(bus->upstream);
+}
+EXPORT_SYMBOL_GPL(sfp_link_down);
+
+int sfp_module_insert(struct sfp_bus *bus, const struct sfp_eeprom_id *id)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+	int ret = 0;
+
+	if (ops && ops->module_insert)
+		ret = ops->module_insert(bus->upstream, id);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sfp_module_insert);
+
+void sfp_module_remove(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+
+	if (ops && ops->module_remove)
+		ops->module_remove(bus->upstream);
+}
+EXPORT_SYMBOL_GPL(sfp_module_remove);
+
+struct sfp_bus *sfp_register_socket(struct device *dev, struct sfp *sfp,
+				    const struct sfp_socket_ops *ops)
+{
+	struct sfp_bus *bus = sfp_bus_get(dev->of_node);
+	int ret = 0;
+
+	if (bus) {
+		rtnl_lock();
+		bus->sfp_dev = dev;
+		bus->sfp = sfp;
+		bus->socket_ops = ops;
+
+		if (bus->netdev)
+			ret = sfp_register_bus(bus);
+		rtnl_unlock();
+	}
+
+	if (ret) {
+		sfp_bus_put(bus);
+		bus = NULL;
+	}
+
+	return bus;
+}
+EXPORT_SYMBOL_GPL(sfp_register_socket);
+
+void sfp_unregister_socket(struct sfp_bus *bus)
+{
+	rtnl_lock();
+	sfp_unregister_bus(bus);
+	bus->sfp_dev = NULL;
+	bus->sfp = NULL;
+	bus->socket_ops = NULL;
+	rtnl_unlock();
+
+	sfp_bus_put(bus);
+}
+EXPORT_SYMBOL_GPL(sfp_unregister_socket);
diff --git a/drivers/net/phy/sfp.h b/drivers/net/phy/sfp.h
new file mode 100644
index 000000000000..31b0acf337e2
--- /dev/null
+++ b/drivers/net/phy/sfp.h
@@ -0,0 +1,28 @@
+#ifndef SFP_H
+#define SFP_H
+
+#include <linux/ethtool.h>
+#include <linux/sfp.h>
+
+struct sfp;
+
+struct sfp_socket_ops {
+	void (*start)(struct sfp *sfp);
+	void (*stop)(struct sfp *sfp);
+	int (*module_info)(struct sfp *sfp, struct ethtool_modinfo *modinfo);
+	int (*module_eeprom)(struct sfp *sfp, struct ethtool_eeprom *ee,
+			     u8 *data);
+};
+
+int sfp_add_phy(struct sfp_bus *bus, struct phy_device *phydev);
+void sfp_remove_phy(struct sfp_bus *bus);
+void sfp_link_up(struct sfp_bus *bus);
+void sfp_link_down(struct sfp_bus *bus);
+int sfp_module_insert(struct sfp_bus *bus, const struct sfp_eeprom_id *id);
+void sfp_module_remove(struct sfp_bus *bus);
+int sfp_link_configure(struct sfp_bus *bus, const struct sfp_eeprom_id *id);
+struct sfp_bus *sfp_register_socket(struct device *dev, struct sfp *sfp,
+				    const struct sfp_socket_ops *ops);
+void sfp_unregister_socket(struct sfp_bus *bus);
+
+#endif