topology: An element can refer to multipe data sections in text conf file

Previously in text conf file, an element can only refer to one data
section (SectionData). Now it can also refer to a list of data sections.
Thus users can split groups of firmware parameters to multiple data
sections, and put them all in the reference list.

Finally, data of these data sections will be merged, in the same order as
they are in the reference list, as the element's private data for kernel.

We still support the original syntax of reference to a single data
section. The doc is updated for the syntax extension.

Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 28 insertions, 0 deletions

diff --git a/include/topology.h b/include/topology.h
index 9d57ce3b..d666505f 100644
--- a/include/topology.h
+++ b/include/topology.h
@@ -213,6 +213,34 @@ extern "C" {
  * The keyword tuples is to define vendor specific tuples. Please refer to
  * section Vendor Tokens and Vendor tuples.
  *
+ * <h5>How to define an element with private data</h5>
+ * An element can refer to a single data section or multiple data
+ * sections.
+ *
+ * <h6>To refer to a single data section:</h6>
+ * <pre>
+ * Sectionxxx."element name" {
+ *    ...
+ *	data "name of data section"		# optional private data
+ * }
+ * </pre>
+ *
+ * <h6>To refer to multiple data sections:</h6>
+ * <pre>
+ * Sectionxxx."element name" {
+ *	...
+ *	data [						# optional private data
+ *		"name of 1st data section"
+ *		"name of 2nd data section"
+ *		...
+ *	]
+ * }
+ * </pre>
+ * And data of these sections will be merged in the same order as they are
+ * in the list, as the element's private data for kernel.
+ *
+ * </pre>
+ *
  *  <h6>Vendor Tokens</h6>
  * A vendor token list is defined as a new section. Each token element is
  * a pair of string ID and integer value. And both the ID and value are