[PATCH net v4 1/4] net: phy: add PHY package locking helpers

From: Xuanqiang Luo <[email protected]>

The PHY package API provides private data shared by all PHYs in a
package. Drivers are responsible for synchronizing access to this data,
but the API does not provide a lock for that purpose.

Add phy_package_lock() and phy_package_unlock() for drivers to serialize
access to package-private data, including its initialization.

Signed-off-by: Xuanqiang Luo <[email protected]>
---
 drivers/net/phy/phy_package.c | 23 +++++++++++++++++++++++
 drivers/net/phy/phylib.h      |  2 ++
 2 files changed, 25 insertions(+)

diff --git a/drivers/net/phy/phy_package.c b/drivers/net/phy/phy_package.c
index 16ae8d1c1f89a..735806c5bea88 100644
--- a/drivers/net/phy/phy_package.c
+++ b/drivers/net/phy/phy_package.c
@@ -52,6 +52,29 @@ void *phy_package_get_priv(struct phy_device *phydev)
 }
 EXPORT_SYMBOL_GPL(phy_package_get_priv);
 
+/**
+ * phy_package_lock - acquire the PHY package lock
+ * @phydev: PHY device that has joined the package
+ *
+ * Use this to serialize access to package-private data. Release the lock
+ * with phy_package_unlock().
+ */
+void phy_package_lock(struct phy_device *phydev)
+{
+	mutex_lock(&phydev->mdio.bus->shared_lock);
+}
+EXPORT_SYMBOL_GPL(phy_package_lock);
+
+/**
+ * phy_package_unlock - release the PHY package lock
+ * @phydev: PHY device that has joined the package
+ */
+void phy_package_unlock(struct phy_device *phydev)
+{
+	mutex_unlock(&phydev->mdio.bus->shared_lock);
+}
+EXPORT_SYMBOL_GPL(phy_package_unlock);
+
 static int phy_package_address(struct phy_device *phydev,
 			       unsigned int addr_offset)
 {
diff --git a/drivers/net/phy/phylib.h b/drivers/net/phy/phylib.h
index 0fba245f97458..c6e26ac6b28f0 100644
--- a/drivers/net/phy/phylib.h
+++ b/drivers/net/phy/phylib.h
@@ -12,6 +12,8 @@ struct mii_bus;
 
 struct device_node *phy_package_get_node(struct phy_device *phydev);
 void *phy_package_get_priv(struct phy_device *phydev);
+void phy_package_lock(struct phy_device *phydev);
+void phy_package_unlock(struct phy_device *phydev);
 int __phy_package_read(struct phy_device *phydev, unsigned int addr_offset,
 		       u32 regnum);
 int __phy_package_write(struct phy_device *phydev, unsigned int addr_offset,
-- 
2.43.0