[net-next PATCH v6 03/10] net: phy: add devm/of_phy_package_join helper

[Christian Marangi <ansuelsmth@gmail.com>]

Add devm/of_phy_package_join helper to join PHYs in a PHY package. These
are variant of the manual phy_package_join with the difference that
these will use DT nodes to derive the base_addr instead of manually
passing an hardcoded value.

An additional value is added in phy_package_shared, "np" to reference
the PHY package node pointer in specific PHY driver probe_once and
config_init_once functions to make use of additional specific properties
defined in the PHY package node in DT.

The np value is filled only with of_phy_package_join if a valid PHY
package node is found. A valid PHY package node must have the node name
set to "ethernet-phy-package".

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/net/phy/phy_device.c | 96 ++++++++++++++++++++++++++++++++++++
 include/linux/phy.h          |  6 +++
 2 files changed, 102 insertions(+)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 52828d1c64f7..c30907dc9fb7 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1708,6 +1708,7 @@ int phy_package_join(struct phy_device *phydev, int base_addr, size_t priv_size)
 			shared->priv_size = priv_size;
 		}
 		shared->base_addr = base_addr;
+		shared->np = NULL;
 		refcount_set(&shared->refcnt, 1);
 		bus->shared[base_addr] = shared;
 	} else {
@@ -1730,6 +1731,63 @@ int phy_package_join(struct phy_device *phydev, int base_addr, size_t priv_size)
 }
 EXPORT_SYMBOL_GPL(phy_package_join);
 
+/**
+ * of_phy_package_join - join a common PHY group in PHY package
+ * @phydev: target phy_device struct
+ * @priv_size: if non-zero allocate this amount of bytes for private data
+ *
+ * This is a variant of phy_package_join for PHY package defined in DT.
+ *
+ * The parent node of the @phydev is checked as a valid PHY package node
+ * structure (by matching the node name "ethernet-phy-package") and the
+ * base_addr for the PHY package is passed to phy_package_join.
+ *
+ * With this configuration the shared struct will also have the np value
+ * filled to use additional DT defined properties in PHY specific
+ * probe_once and config_init_once PHY package OPs.
+ *
+ * Returns < 0 on error, 0 on success. Esp. calling phy_package_join()
+ * with the same cookie but a different priv_size is an error. Or a parent
+ * node is not detected or is not valid or doesn't match the expected node
+ * name for PHY package.
+ */
+int of_phy_package_join(struct phy_device *phydev, size_t priv_size)
+{
+	struct device_node *node = phydev->mdio.dev.of_node;
+	struct device_node *package_node;
+	u32 base_addr;
+	int ret;
+
+	if (!node)
+		return -EINVAL;
+
+	package_node = of_get_parent(node);
+	if (!package_node)
+		return -EINVAL;
+
+	if (!of_node_name_eq(package_node, "ethernet-phy-package")) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	if (of_property_read_u32(package_node, "reg", &base_addr)) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	ret = phy_package_join(phydev, base_addr, priv_size);
+	if (ret)
+		goto exit;
+
+	phydev->shared->np = package_node;
+
+	return 0;
+exit:
+	of_node_put(package_node);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(of_phy_package_join);
+
 /**
  * phy_package_leave - leave a common PHY group
  * @phydev: target phy_device struct
@@ -1746,6 +1804,10 @@ void phy_package_leave(struct phy_device *phydev)
 	if (!shared)
 		return;
 
+	/* Decrease the node refcount on leave if present */
+	if (shared->np)
+		of_node_put(shared->np);
+
 	if (refcount_dec_and_mutex_lock(&shared->refcnt, &bus->shared_lock)) {
 		bus->shared[shared->base_addr] = NULL;
 		mutex_unlock(&bus->shared_lock);
@@ -1798,6 +1860,40 @@ int devm_phy_package_join(struct device *dev, struct phy_device *phydev,
 }
 EXPORT_SYMBOL_GPL(devm_phy_package_join);
 
+/**
+ * devm_of_phy_package_join - resource managed of_phy_package_join()
+ * @dev: device that is registering this PHY package
+ * @phydev: target phy_device struct
+ * @priv_size: if non-zero allocate this amount of bytes for private data
+ *
+ * Managed of_phy_package_join(). Shared storage fetched by this function,
+ * phy_package_leave() is automatically called on driver detach. See
+ * of_phy_package_join() for more information.
+ */
+int devm_of_phy_package_join(struct device *dev, struct phy_device *phydev,
+			     size_t priv_size)
+{
+	struct phy_device **ptr;
+	int ret;
+
+	ptr = devres_alloc(devm_phy_package_leave, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = of_phy_package_join(phydev, priv_size);
+
+	if (!ret) {
+		*ptr = phydev;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devm_of_phy_package_join);
+
 /**
  * phy_detach - detach a PHY device from its network device
  * @phydev: target phy_device struct
diff --git a/include/linux/phy.h b/include/linux/phy.h
index a66f07d3f5f4..2aed925e6c23 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -329,6 +329,7 @@ struct mdio_bus_stats {
  * struct phy_package_shared - Shared information in PHY packages
  * @base_addr: Base PHY address of PHY package used to combine PHYs
  *   in one package and for offset calculation of phy_package_read/write
+ * @np: Pointer to the Device Node if PHY package defined in DT
  * @refcnt: Number of PHYs connected to this shared data
  * @flags: Initialization of PHY package
  * @priv_size: Size of the shared private data @priv
@@ -340,6 +341,8 @@ struct mdio_bus_stats {
  */
 struct phy_package_shared {
 	u8 base_addr;
+	/* With PHY package defined in DT this points to the PHY package node */
+	struct device_node *np;
 	refcount_t refcnt;
 	unsigned long flags;
 	size_t priv_size;
@@ -1999,9 +2002,12 @@ int phy_ethtool_set_link_ksettings(struct net_device *ndev,
 				   const struct ethtool_link_ksettings *cmd);
 int phy_ethtool_nway_reset(struct net_device *ndev);
 int phy_package_join(struct phy_device *phydev, int base_addr, size_t priv_size);
+int of_phy_package_join(struct phy_device *phydev, size_t priv_size);
 void phy_package_leave(struct phy_device *phydev);
 int devm_phy_package_join(struct device *dev, struct phy_device *phydev,
 			  int base_addr, size_t priv_size);
+int devm_of_phy_package_join(struct device *dev, struct phy_device *phydev,
+			     size_t priv_size);
 
 int __init mdio_bus_init(void);
 void mdio_bus_exit(void);
-- 
2.43.0