tdm_output_get_pipe(tdm_output *output, unsigned int *pipe);
/**
+ * @brief Get the index of a primary layer.
+ * @param[in] output A output object
+ * @param[out] index The primary layer index
+ * @return #TDM_ERROR_NONE if success. Otherwise, error value.
+ */
+tdm_error
+tdm_output_get_primary_index(tdm_output *output, int *index);
+
+/**
* @brief Set the property which has a given id.
* @param[in] output A output object
* @param[in] id The property id