net: mdiobus: search for PSE nodes by parsing PHY nodes.

Some PHYs can be linked with PSE (Power Sourcing Equipment), so search
for related nodes and attach it to the phydev.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/mdio/fwnode_mdio.c

@@ -10,10 +10,31 @@
 #include <linux/fwnode_mdio.h>
 #include <linux/of.h>
 #include <linux/phy.h>
+#include <linux/pse-pd/pse.h>
 
 MODULE_AUTHOR("Calvin Johnson <calvin.johnson@oss.nxp.com>");
 MODULE_LICENSE("GPL");
 
+static struct pse_control *
+fwnode_find_pse_control(struct fwnode_handle *fwnode)
+{
+	struct pse_control *psec;
+	struct device_node *np;
+
+	if (!IS_ENABLED(CONFIG_PSE_CONTROLLER))
+		return NULL;
+
+	np = to_of_node(fwnode);
+	if (!np)
+		return NULL;
+
+	psec = of_pse_control_get(np);
+	if (PTR_ERR(psec) == -ENOENT)
+		return NULL;
+
+	return psec;
+}
+
 static struct mii_timestamper *
 fwnode_find_mii_timestamper(struct fwnode_handle *fwnode)
 {
@@ -91,14 +112,21 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus,
 				struct fwnode_handle *child, u32 addr)
 {
 	struct mii_timestamper *mii_ts = NULL;
+	struct pse_control *psec = NULL;
 	struct phy_device *phy;
 	bool is_c45 = false;
 	u32 phy_id;
 	int rc;
 
+	psec = fwnode_find_pse_control(child);
+	if (IS_ERR(psec))
+		return PTR_ERR(psec);
+
 	mii_ts = fwnode_find_mii_timestamper(child);
-	if (IS_ERR(mii_ts))
-		return PTR_ERR(mii_ts);
+	if (IS_ERR(mii_ts)) {
+		rc = PTR_ERR(mii_ts);
+		goto clean_pse;
+	}
 
 	rc = fwnode_property_match_string(child, "compatible",
 					  "ethernet-phy-ieee802.3-c45");
@@ -134,18 +162,23 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus,
 			goto clean_phy;
 	}
 
+	phy->psec = psec;
+
 	/* phy->mii_ts may already be defined by the PHY driver. A
 	 * mii_timestamper probed via the device tree will still have
 	 * precedence.
 	 */
 	if (mii_ts)
 		phy->mii_ts = mii_ts;
+
 	return 0;
 
 clean_phy:
 	phy_device_free(phy);
 clean_mii_ts:
 	unregister_mii_timestamper(mii_ts);
+clean_pse:
+	pse_control_put(psec);
 
 	return rc;
 }

drivers/net/phy/phy_device.c

@@ -26,6 +26,7 @@
 #include <linux/netdevice.h>
 #include <linux/phy.h>
 #include <linux/phy_led_triggers.h>
+#include <linux/pse-pd/pse.h>
 #include <linux/property.h>
 #include <linux/sfp.h>
 #include <linux/skbuff.h>
@@ -991,6 +992,7 @@ EXPORT_SYMBOL(phy_device_register);
 void phy_device_remove(struct phy_device *phydev)
 {
 	unregister_mii_timestamper(phydev->mii_ts);
+	pse_control_put(phydev->psec);
 
 	device_del(&phydev->mdio.dev);
 

include/linux/phy.h

@@ -597,6 +597,7 @@ struct macsec_ops;
  * @master_slave_get: Current master/slave advertisement
  * @master_slave_state: Current master/slave configuration
  * @mii_ts: Pointer to time stamper callbacks
+ * @psec: Pointer to Power Sourcing Equipment control struct
  * @lock:  Mutex for serialization access to PHY
  * @state_queue: Work queue for state machine
  * @shared: Pointer to private data shared by phys in one package
@@ -715,6 +716,7 @@ struct phy_device {
 	struct phylink *phylink;
 	struct net_device *attached_dev;
 	struct mii_timestamper *mii_ts;
+	struct pse_control *psec;
 
 	u8 mdix;
 	u8 mdix_ctrl;