[PATCH v16 2/5] phy: core: Add phy_get_by_of_node()

[Bryan O'Donoghue]

Add new function phy_get_by_of_node() allowing lookup of a phy by
device_node. Separates existing logic in _of_phy_get() into an internal
helper method _of_phy_get_with_args() to allow for reuse in new method.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue at linaro.org>
---
 drivers/phy/phy-core.c  | 95 +++++++++++++++++++++++++++++++++++++------------
 include/linux/phy/phy.h |  6 ++++
 2 files changed, 78 insertions(+), 23 deletions(-)

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 89addd732bff3..490a7cde6d40a 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -606,22 +606,51 @@ int phy_validate(struct phy *phy, enum phy_mode mode, int submode,
 }
 EXPORT_SYMBOL_GPL(phy_validate);
 
+/**
+ * _of_phy_get_with_args() - lookup and obtain a reference to a phy by of_phandle_args
+ * @args: of_phandle_args to the phy
+ *
+ * Returns the phy from the provider's of_xlate, -ENODEV if disabled,
+ * -EPROBE_DEFER if the provider is not yet registered.
+ */
+static struct phy *_of_phy_get_with_args(struct of_phandle_args *args)
+{
+	struct phy *phy;
+	struct phy_provider *phy_provider;
+
+	lockdep_assert_held(&phy_provider_mutex);
+
+	phy_provider = of_phy_provider_lookup(args->np);
+	if (IS_ERR(phy_provider) || !try_module_get(phy_provider->owner))
+		return ERR_PTR(-EPROBE_DEFER);
+
+	if (!of_device_is_available(args->np)) {
+		dev_warn(phy_provider->dev, "Requested PHY is disabled\n");
+		phy = ERR_PTR(-ENODEV);
+		goto out_put_module;
+	}
+
+	phy = phy_provider->of_xlate(phy_provider->dev, args);
+
+out_put_module:
+	module_put(phy_provider->owner);
+
+	return phy;
+}
+
 /**
  * _of_phy_get() - lookup and obtain a reference to a phy by phandle
  * @np: device_node for which to get the phy
  * @index: the index of the phy
  *
- * Returns the phy associated with the given phandle value,
- * after getting a refcount to it or -ENODEV if there is no such phy or
- * -EPROBE_DEFER if there is a phandle to the phy, but the device is
- * not yet loaded. This function uses of_xlate call back function provided
- * while registering the phy_provider to find the phy instance.
+ * Returns the phy associated with the given phandle value after getting
+ * a refcount to it; -ENODEV if there is no such phy or the phy is
+ * disabled; -EPROBE_DEFER if the phy provider is not yet available.
  */
 static struct phy *_of_phy_get(struct device_node *np, int index)
 {
 	int ret;
-	struct phy_provider *phy_provider;
-	struct phy *phy = NULL;
+	struct phy *phy;
 	struct of_phandle_args args;
 
 	lockdep_assert_held(&phy_provider_mutex);
@@ -637,22 +666,7 @@ static struct phy *_of_phy_get(struct device_node *np, int index)
 		goto out_put_node;
 	}
 
-	phy_provider = of_phy_provider_lookup(args.np);
-	if (IS_ERR(phy_provider) || !try_module_get(phy_provider->owner)) {
-		phy = ERR_PTR(-EPROBE_DEFER);
-		goto out_put_node;
-	}
-
-	if (!of_device_is_available(args.np)) {
-		dev_warn(phy_provider->dev, "Requested PHY is disabled\n");
-		phy = ERR_PTR(-ENODEV);
-		goto out_put_module;
-	}
-
-	phy = phy_provider->of_xlate(phy_provider->dev, &args);
-
-out_put_module:
-	module_put(phy_provider->owner);
+	phy = _of_phy_get_with_args(&args);
 
 out_put_node:
 	of_node_put(args.np);
@@ -1001,6 +1015,41 @@ struct phy *devm_of_phy_get_by_index(struct device *dev, struct device_node *np,
 }
 EXPORT_SYMBOL_GPL(devm_of_phy_get_by_index);
 
+/**
+ * phy_get_by_of_node() - lookup and obtain a reference to a phy by device_node
+ * @np: node containing the phy
+ *
+ * Returns the phy associated with the device node or ERR_PTR.
+ */
+struct phy *phy_get_by_of_node(struct device_node *np)
+{
+	struct of_phandle_args args = { .np = np, .args_count = 0 };
+	struct phy *phy;
+
+	if (!np)
+		return ERR_PTR(-EINVAL);
+
+	mutex_lock(&phy_provider_mutex);
+
+	phy = _of_phy_get_with_args(&args);
+
+	if (IS_ERR(phy))
+		goto out_unlock;
+
+	if (!try_module_get(phy->ops->owner)) {
+		phy = ERR_PTR(-EPROBE_DEFER);
+		goto out_unlock;
+	}
+
+	get_device(&phy->dev);
+
+out_unlock:
+	mutex_unlock(&phy_provider_mutex);
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(phy_get_by_of_node);
+
 /**
  * phy_create() - create a new phy
  * @dev: device that is creating the new phy
diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
index ea47975e288ae..71c2e16397130 100644
--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h
@@ -284,6 +284,7 @@ struct phy *devm_of_phy_optional_get(struct device *dev, struct device_node *np,
 				     const char *con_id);
 struct phy *devm_of_phy_get_by_index(struct device *dev, struct device_node *np,
 				     int index);
+struct phy *phy_get_by_of_node(struct device_node *np);
 void of_phy_put(struct phy *phy);
 void phy_put(struct device *dev, struct phy *phy);
 void devm_phy_put(struct device *dev, struct phy *phy);
@@ -493,6 +494,11 @@ static inline struct phy *devm_of_phy_get_by_index(struct device *dev,
 	return ERR_PTR(-ENOSYS);
 }
 
+static inline struct phy *phy_get_by_of_node(struct device_node *np)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
 static inline void of_phy_put(struct phy *phy)
 {
 }

-- 
2.55.0