power: Add devm_power_supply_get_by_phandle() helper function

This commit adds a resource-managed version of the
power_supply_get_by_phandle() function.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

2 files changed, 44 insertions, 0 deletions

diff --git a/drivers/power/power_supply_core.c b/drivers/power/power_supply_core.c
index 4bc0c7f459a5..a44d4554af4f 100644
--- a/drivers/power/power_supply_core.c
+++ b/drivers/power/power_supply_core.c
@@ -446,6 +446,45 @@ struct power_supply *power_supply_get_by_phandle(struct device_node *np,
         return psy;
 }
 EXPORT_SYMBOL_GPL(power_supply_get_by_phandle);
+
+static void devm_power_supply_put(struct device *dev, void *res)
+{
+        struct power_supply **psy = res;
+
+        power_supply_put(*psy);
+}
+
+/**
+ * devm_power_supply_get_by_phandle() - Resource managed version of
+ *  power_supply_get_by_phandle()
+ * @dev: Pointer to device holding phandle property
+ * @phandle_name: Name of property holding a power supply phandle
+ *
+ * Return: On success returns a reference to a power supply with
+ * matching name equals to value under @property, NULL or ERR_PTR otherwise.
+ */
+struct power_supply *devm_power_supply_get_by_phandle(struct device *dev,
+                                                      const char *property)
+{
+        struct power_supply **ptr, *psy;
+
+        if (!dev->of_node)
+                return ERR_PTR(-ENODEV);
+
+        ptr = devres_alloc(devm_power_supply_put, sizeof(*ptr), GFP_KERNEL);
+        if (!ptr)
+                return ERR_PTR(-ENOMEM);
+
+        psy = power_supply_get_by_phandle(dev->of_node, property);
+        if (IS_ERR_OR_NULL(psy)) {
+                devres_free(ptr);
+        } else {
+                *ptr = psy;
+                devres_add(dev, ptr);
+        }
+        return psy;
+}
+EXPORT_SYMBOL_GPL(devm_power_supply_get_by_phandle);
 #endif /* CONFIG_OF */
 
 int power_supply_get_property(struct power_supply *psy,
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index 0395bcb18ddb..ef9f1592185d 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -292,10 +292,15 @@ extern void power_supply_put(struct power_supply *psy);
 #ifdef CONFIG_OF
 extern struct power_supply *power_supply_get_by_phandle(struct device_node *np,
                                                         const char *property);
+extern struct power_supply *devm_power_supply_get_by_phandle(
+                                    struct device *dev, const char *property);
 #else /* !CONFIG_OF */
 static inline struct power_supply *
 power_supply_get_by_phandle(struct device_node *np, const char *property)
 { return NULL; }
+static inline struct power_supply *
+devm_power_supply_get_by_phandle(struct device *dev, const char *property)
+{ return NULL; }
 #endif /* CONFIG_OF */
 extern void power_supply_changed(struct power_supply *psy);
 extern int power_supply_am_i_supplied(struct power_supply *psy);