[PATCH net-next v2 06/12] net: sfp: Add a sfp-bus ops when connecting a module without PHY

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

The SFP bus infrastructure notifies its upstream when a PHY device was
discovered on the module. However, we don't have any indication when a
module with no PHY was inserted, except for the .insert() and .start()
notifications.

We want to keep track of the SFP module's capabilities using phy_port.
When the module contains an embedded PHY, the PHY driver will expose a
phy_port for it. However when there's no PHY, we have no hook to
populate the phy_port, so let's introduce one. It is called when we
have parsed the module's caps, applied the fixups, tried and failed to
probe for a PHY.

This will allow the bus' upstream to create the corresponding port, and
register it to the topology.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
---
 drivers/net/phy/sfp-bus.c | 20 ++++++++++++++++++++
 drivers/net/phy/sfp.c     | 14 ++++++++++++++
 drivers/net/phy/sfp.h     |  2 ++
 include/linux/sfp.h       |  5 +++++
 4 files changed, 41 insertions(+)

diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index b945d75966d5..a3d9e28badd0 100644
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -753,6 +753,26 @@ void sfp_remove_phy(struct sfp_bus *bus)
 }
 EXPORT_SYMBOL_GPL(sfp_remove_phy);
 
+int sfp_module_connect_nophy(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+
+	if (ops && ops->connect_nophy)
+		return ops->connect_nophy(bus->upstream);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sfp_module_connect_nophy);
+
+void sfp_module_disconnect_nophy(struct sfp_bus *bus)
+{
+	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
+
+	if (ops && ops->disconnect_nophy)
+		ops->disconnect_nophy(bus->upstream);
+}
+EXPORT_SYMBOL_GPL(sfp_module_disconnect_nophy);
+
 void sfp_link_up(struct sfp_bus *bus)
 {
 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 47f095bd91ce..050952bc7bce 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -1918,6 +1918,11 @@ static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
 	return 0;
 }
 
+static int sfp_sm_connect_nophy(struct sfp *sfp)
+{
+	return sfp_module_connect_nophy(sfp->sfp_bus);
+}
+
 static void sfp_sm_link_up(struct sfp *sfp)
 {
 	sfp_link_up(sfp->sfp_bus);
@@ -2646,6 +2651,8 @@ static void sfp_sm_main(struct sfp *sfp, unsigned int event)
 			sfp_module_stop(sfp->sfp_bus);
 		if (sfp->mod_phy)
 			sfp_sm_phy_detach(sfp);
+		else
+			sfp_module_disconnect_nophy(sfp->sfp_bus);
 		if (sfp->i2c_mii)
 			sfp_i2c_mdiobus_destroy(sfp);
 		sfp_module_tx_disable(sfp);
@@ -2749,6 +2756,13 @@ static void sfp_sm_main(struct sfp *sfp, unsigned int event)
 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
 			break;
 		}
+		if (!sfp->mod_phy) {
+			ret = sfp_sm_connect_nophy(sfp);
+			if (ret) {
+				sfp_sm_next(sfp, SFP_S_FAIL, 0);
+				break;
+			}
+		}
 		if (sfp_module_start(sfp->sfp_bus)) {
 			sfp_sm_next(sfp, SFP_S_FAIL, 0);
 			break;
diff --git a/drivers/net/phy/sfp.h b/drivers/net/phy/sfp.h
index 879dff7afe6a..02f3814aac84 100644
--- a/drivers/net/phy/sfp.h
+++ b/drivers/net/phy/sfp.h
@@ -37,6 +37,8 @@ int sfp_module_insert(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 void sfp_module_remove(struct sfp_bus *bus);
 int sfp_module_start(struct sfp_bus *bus);
 void sfp_module_stop(struct sfp_bus *bus);
+int sfp_module_connect_nophy(struct sfp_bus *bus);
+void sfp_module_disconnect_nophy(struct sfp_bus *bus);
 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);
diff --git a/include/linux/sfp.h b/include/linux/sfp.h
index 5c71945a5e4d..1c18de1eb268 100644
--- a/include/linux/sfp.h
+++ b/include/linux/sfp.h
@@ -561,6 +561,9 @@ struct sfp_module_caps {
  *   on the module.
  * @disconnect_phy: called when a module with an I2C accessible PHY has
  *   been removed.
+ * @connect_nophy: called when it was established that the connected module
+ *		   doesn't have an I2C PHY accessible.
+ * @disconnect_nophy: called when the PHY-less module has been removed.
  */
 struct sfp_upstream_ops {
 	void (*attach)(void *priv, struct sfp_bus *bus);
@@ -573,6 +576,8 @@ struct sfp_upstream_ops {
 	void (*link_up)(void *priv);
 	int (*connect_phy)(void *priv, struct phy_device *);
 	void (*disconnect_phy)(void *priv, struct phy_device *);
+	int (*connect_nophy)(void *priv);
+	void (*disconnect_nophy)(void *priv);
 };
 
 #if IS_ENABLED(CONFIG_SFP)
-- 
2.49.0