diff --git a/include/linux/extcon.h b/include/linux/extcon.h
index 744d60c..6d94e82 100644
--- a/include/linux/extcon.h
+++ b/include/linux/extcon.h
@@ -1,5 +1,6 @@
 /*
  * External Connector (extcon) framework
+ * - linux/include/linux/extcon.h for extcon consumer device driver.
  *
  * Copyright (C) 2015 Samsung Electronics
  * Author: Chanwoo Choi <cw00.choi@samsung.com>
@@ -170,61 +171,29 @@ union extcon_property_value {
 	int intval;	/* type : integer (intval) */
 };
 
-struct extcon_cable;
 struct extcon_dev;
 
 #if IS_ENABLED(CONFIG_EXTCON)
-
-/* Following APIs register/unregister the extcon device. */
-extern int extcon_dev_register(struct extcon_dev *edev);
-extern void extcon_dev_unregister(struct extcon_dev *edev);
-extern int devm_extcon_dev_register(struct device *dev,
-				struct extcon_dev *edev);
-extern void devm_extcon_dev_unregister(struct device *dev,
-				struct extcon_dev *edev);
-
-/* Following APIs allocate/free the memory of the extcon device. */
-extern struct extcon_dev *extcon_dev_allocate(const unsigned int *cable);
-extern void extcon_dev_free(struct extcon_dev *edev);
-extern struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
-				const unsigned int *cable);
-extern void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev);
-
-/* Synchronize the state and property value for each external connector. */
-extern int extcon_sync(struct extcon_dev *edev, unsigned int id);
-
 /*
- * Following APIs get/set the connected state of each external connector.
+ * Following APIs get the connected state of each external connector.
  * The 'id' argument indicates the defined external connector.
  */
 extern int extcon_get_state(struct extcon_dev *edev, unsigned int id);
-extern int extcon_set_state(struct extcon_dev *edev, unsigned int id,
-				bool state);
-extern int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id,
-				bool state);
 
 /*
- * Following APIs get/set the property of each external connector.
+ * Following APIs get the property of each external connector.
  * The 'id' argument indicates the defined external connector
  * and the 'prop' indicates the extcon property.
  *
- * And extcon_get/set_property_capability() set the capability of the property
- * for each external connector. They are used to set the capability of the
+ * And extcon_get_property_capability() get the capability of the property
+ * for each external connector. They are used to get the capability of the
  * property of each external connector based on the id and property.
  */
 extern int extcon_get_property(struct extcon_dev *edev, unsigned int id,
 				unsigned int prop,
 				union extcon_property_value *prop_val);
-extern int extcon_set_property(struct extcon_dev *edev, unsigned int id,
-				unsigned int prop,
-				union extcon_property_value prop_val);
-extern int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
-				unsigned int prop,
-				union extcon_property_value prop_val);
 extern int extcon_get_property_capability(struct extcon_dev *edev,
 				unsigned int id, unsigned int prop);
-extern int extcon_set_property_capability(struct extcon_dev *edev,
-				unsigned int id, unsigned int prop);
 
 /*
  * Following APIs register the notifier block in order to detect
@@ -268,79 +237,17 @@ extern struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 extern const char *extcon_get_edev_name(struct extcon_dev *edev);
 
 #else /* CONFIG_EXTCON */
-static inline int extcon_dev_register(struct extcon_dev *edev)
-{
-	return 0;
-}
-
-static inline void extcon_dev_unregister(struct extcon_dev *edev) { }
-
-static inline int devm_extcon_dev_register(struct device *dev,
-				struct extcon_dev *edev)
-{
-	return -EINVAL;
-}
-
-static inline void devm_extcon_dev_unregister(struct device *dev,
-				struct extcon_dev *edev) { }
-
-static inline struct extcon_dev *extcon_dev_allocate(const unsigned int *cable)
-{
-	return ERR_PTR(-ENOSYS);
-}
-
-static inline void extcon_dev_free(struct extcon_dev *edev) { }
-
-static inline struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
-				const unsigned int *cable)
-{
-	return ERR_PTR(-ENOSYS);
-}
-
-static inline void devm_extcon_dev_free(struct extcon_dev *edev) { }
-
-
 static inline int extcon_get_state(struct extcon_dev *edev, unsigned int id)
 {
 	return 0;
 }
 
-static inline int extcon_set_state(struct extcon_dev *edev, unsigned int id,
-				bool state)
-{
-	return 0;
-}
-
-static inline int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id,
-				bool state)
-{
-	return 0;
-}
-
-static inline int extcon_sync(struct extcon_dev *edev, unsigned int id)
-{
-	return 0;
-}
-
 static inline int extcon_get_property(struct extcon_dev *edev, unsigned int id,
 				unsigned int prop,
 				union extcon_property_value *prop_val)
 {
 	return 0;
 }
-static inline int extcon_set_property(struct extcon_dev *edev, unsigned int id,
-				unsigned int prop,
-				union extcon_property_value prop_val)
-{
-	return 0;
-}
-
-static inline int extcon_set_property_sync(struct extcon_dev *edev,
-				unsigned int id, unsigned int prop,
-				union extcon_property_value prop_val)
-{
-	return 0;
-}
 
 static inline int extcon_get_property_capability(struct extcon_dev *edev,
 				unsigned int id, unsigned int prop)
@@ -348,12 +255,6 @@ static inline int extcon_get_property_capability(struct extcon_dev *edev,
 	return 0;
 }
 
-static inline int extcon_set_property_capability(struct extcon_dev *edev,
-				unsigned int id, unsigned int prop)
-{
-	return 0;
-}
-
 static inline int extcon_register_notifier(struct extcon_dev *edev,
 				unsigned int id, struct notifier_block *nb)
 {