2 files changed, 93 insertions, 0 deletions

diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index 0342be39cae2..a76655c2ddef 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -27,6 +27,38 @@
 #include <media/media-device.h>
 
 /**
+ *  media_gobj_init - Initialize a graph object
+ *
+ * @mdev:	Pointer to the media_device that contains the object
+ * @type:	Type of the object
+ * @gobj:	Pointer to the object
+ *
+ * This routine initializes the embedded struct media_gobj inside a
+ * media graph object. It is called automatically if media_*_create()
+ * calls are used. However, if the object (entity, link, pad, interface)
+ * is embedded on some other object, this function should be called before
+ * registering the object at the media controller.
+ */
+void media_gobj_init(struct media_device *mdev,
+			   enum media_gobj_type type,
+			   struct media_gobj *gobj)
+{
+	/* For now, nothing to do */
+}
+
+/**
+ *  media_gobj_remove - Stop using a graph object on a media device
+ *
+ * @graph_obj:	Pointer to the object
+ *
+ * This should be called at media_device_unregister_*() routines
+ */
+void media_gobj_remove(struct media_gobj *gobj)
+{
+	/* For now, nothing to do */
+}
+
+/**
  * media_entity_init - Initialize a media entity
  *
  * @num_pads: Total number of sink and source pads.
diff --git a/include/media/media-entity.h b/include/media/media-entity.h
index 57881758927e..96626356b8f3 100644
--- a/include/media/media-entity.h
+++ b/include/media/media-entity.h
@@ -28,6 +28,39 @@
 #include <linux/list.h>
 #include <linux/media.h>
 
+/* Enums used internally at the media controller to represent graphs */
+
+/**
+ * enum media_gobj_type - type of a graph object
+ *
+ */
+enum media_gobj_type {
+	 /* FIXME: add the types here, as we embed media_gobj */
+	MEDIA_GRAPH_NONE
+};
+
+#define MEDIA_BITS_PER_TYPE		8
+#define MEDIA_BITS_PER_LOCAL_ID		(32 - MEDIA_BITS_PER_TYPE)
+#define MEDIA_LOCAL_ID_MASK		 GENMASK(MEDIA_BITS_PER_LOCAL_ID - 1, 0)
+
+/* Structs to represent the objects that belong to a media graph */
+
+/**
+ * struct media_gobj - Define a graph object.
+ *
+ * @id:		Non-zero object ID identifier. The ID should be unique
+ *		inside a media_device, as it is composed by
+ *		MEDIA_BITS_PER_TYPE to store the type plus
+ *		MEDIA_BITS_PER_LOCAL_ID	to store a per-type ID
+ *		(called as "local ID").
+ *
+ * All objects on the media graph should have this struct embedded
+ */
+struct media_gobj {
+	u32			id;
+};
+
+
 struct media_pipeline {
 };
 
@@ -118,6 +151,26 @@ static inline u32 media_entity_id(struct media_entity *entity)
 	return entity->id;
 }
 
+static inline enum media_gobj_type media_type(struct media_gobj *gobj)
+{
+	return gobj->id >> MEDIA_BITS_PER_LOCAL_ID;
+}
+
+static inline u32 media_localid(struct media_gobj *gobj)
+{
+	return gobj->id & MEDIA_LOCAL_ID_MASK;
+}
+
+static inline u32 media_gobj_gen_id(enum media_gobj_type type, u32 local_id)
+{
+	u32 id;
+
+	id = type << MEDIA_BITS_PER_LOCAL_ID;
+	id |= local_id & MEDIA_LOCAL_ID_MASK;
+
+	return id;
+}
+
 #define MEDIA_ENTITY_ENUM_MAX_DEPTH	16
 #define MEDIA_ENTITY_ENUM_MAX_ID	64
 
@@ -138,6 +191,14 @@ struct media_entity_graph {
 	int top;
 };
 
+#define gobj_to_entity(gobj) \
+		container_of(gobj, struct media_entity, graph_obj)
+
+void media_gobj_init(struct media_device *mdev,
+		    enum media_gobj_type type,
+		    struct media_gobj *gobj);
+void media_gobj_remove(struct media_gobj *gobj);
+
 int media_entity_init(struct media_entity *entity, u16 num_pads,
 		struct media_pad *pads);
 void media_entity_cleanup(struct media_entity *entity);