media: mc: entity: Add has_pad_interdep entity operation

Add a new media entity operation, has_pad_interdep. The optional op is
used to discover the pad interdependencies inside an entity during the
pipeline construction.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/mc/mc-entity.c

@@ -232,7 +232,10 @@ EXPORT_SYMBOL_GPL(media_entity_pads_init);
  * and enabling one of the pads means that the other pad will become "locked"
  * and doesn't allow configuration changes.
  *
- * For the time being all pads are considered interdependent.
+ * This function uses the &media_entity_operations.has_pad_interdep() operation
+ * to check the dependency inside the entity between @pad0 and @pad1. If the
+ * has_pad_interdep operation is not implemented, all pads of the entity are
+ * considered to be interdependent.
  */
 static bool media_entity_has_pad_interdep(struct media_entity *entity,
 					  unsigned int pad0, unsigned int pad1)
@@ -244,7 +247,10 @@ static bool media_entity_has_pad_interdep(struct media_entity *entity,
 	    (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE))
 		return false;
 
-	return true;
+	if (!entity->ops || !entity->ops->has_pad_interdep)
+		return true;
+
+	return entity->ops->has_pad_interdep(entity, pad0, pad1);
 }
 
 static struct media_entity *

include/media/media-entity.h

@@ -237,6 +237,14 @@ struct media_pad {
  * @link_validate:	Return whether a link is valid from the entity point of
  *			view. The media_pipeline_start() function
  *			validates all links by calling this operation. Optional.
+ * @has_pad_interdep:	Return whether a two pads inside the entity are
+ *			interdependent. If two pads are interdependent they are
+ *			part of the same pipeline and enabling one of the pads
+ *			means that the other pad will become "locked" and
+ *			doesn't allow configuration changes. pad0 and pad1 are
+ *			guaranteed to not both be sinks or sources.
+ *			Optional: If the operation isn't implemented all pads
+ *			will be considered as interdependent.
  *
  * .. note::
  *
@@ -250,6 +258,8 @@ struct media_entity_operations {
 			  const struct media_pad *local,
 			  const struct media_pad *remote, u32 flags);
 	int (*link_validate)(struct media_link *link);
+	bool (*has_pad_interdep)(struct media_entity *entity, unsigned int pad0,
+				 unsigned int pad1);
 };
 
 /**