[PATCH net-next v5 04/13] net: sfp: Add helper to return the SFP bus name

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

Knowing the bus name is helpful when we want to expose the link topology
to userspace, add a helper to return the SFP bus name.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---
V5: - Added Andrew's R-b
V4: - No changes
V3: - Added RTNL assert
    - Made the stub inline
V2: New patch

 drivers/net/phy/sfp-bus.c | 11 +++++++++++
 include/linux/sfp.h       |  6 ++++++
 2 files changed, 17 insertions(+)

diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index 3a86c41e1235..fb1c102714b5 100644
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -859,3 +859,14 @@ void sfp_unregister_socket(struct sfp_bus *bus)
 	sfp_bus_put(bus);
 }
 EXPORT_SYMBOL_GPL(sfp_unregister_socket);
+
+const char *sfp_get_name(struct sfp_bus *bus)
+{
+	ASSERT_RTNL();
+
+	if (bus->sfp_dev)
+		return dev_name(bus->sfp_dev);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(sfp_get_name);
diff --git a/include/linux/sfp.h b/include/linux/sfp.h
index 0573e53b0c11..55c0ab17c9e2 100644
--- a/include/linux/sfp.h
+++ b/include/linux/sfp.h
@@ -570,6 +570,7 @@ struct sfp_bus *sfp_bus_find_fwnode(const struct fwnode_handle *fwnode);
 int sfp_bus_add_upstream(struct sfp_bus *bus, void *upstream,
 			 const struct sfp_upstream_ops *ops);
 void sfp_bus_del_upstream(struct sfp_bus *bus);
+const char *sfp_get_name(struct sfp_bus *bus);
 #else
 static inline int sfp_parse_port(struct sfp_bus *bus,
 				 const struct sfp_eeprom_id *id,
@@ -648,6 +649,11 @@ static inline int sfp_bus_add_upstream(struct sfp_bus *bus, void *upstream,
 static inline void sfp_bus_del_upstream(struct sfp_bus *bus)
 {
 }
+
+static inline const char *sfp_get_name(struct sfp_bus *bus)
+{
+	return NULL;
+}
 #endif
 
 #endif
-- 
2.43.0