buf: introduce ops instead of a single free function

in struct audio_buffer there was only one virtual method
(free). There are probably more coming, so an ops structure
is introduced.

ring buffer which uses audio buffer as a base must adjust,
including using of an audio_buffer_init procedure, what implies
using audio_stream_params located in audio_buffer

Signed-off-by: Marcin Szkudlinski <marcin.szkudlinski@intel.com>

Author: marcinszkudlinski

src/audio/buffers/audio_buffer.c

@@ -91,7 +91,7 @@ void audio_buffer_free(struct sof_audio_buffer *buffer)
 	audio_buffer_free(buffer->secondary_buffer_sink);
 	audio_buffer_free(buffer->secondary_buffer_source);
 #endif /* CONFIG_PIPELINE_2_0 */
-	if (buffer->free)
-		buffer->free(buffer);
+	if (buffer->ops->free)
+		buffer->ops->free(buffer);
 	rfree(buffer);
 }

src/audio/buffers/ring_buffer.c

@@ -271,6 +271,10 @@ static const struct sink_ops ring_buffer_sink_ops = {
 	.audio_set_ipc_params = ring_buffer_set_ipc_params_sink,
 };
 
+static const struct audio_buffer_ops ring_buffer_audio_buffer_ops = {
+	.free = ring_buffer_free,
+};
+
 struct ring_buffer *ring_buffer_create(size_t min_available, size_t min_free_space, uint32_t flags,
 				       uint32_t id,
 				       struct sof_audio_stream_params *audio_stream_params)
@@ -321,7 +325,7 @@ struct ring_buffer *ring_buffer_create(size_t min_available, size_t min_free_spa
 		ring_buffer->data_buffer_size);
 
 	/* set common buffer api */
-	ring_buffer->audio_buffer.free = ring_buffer_free;
+	ring_buffer->audio_buffer.ops = &ring_buffer_audio_buffer_ops;
 	ring_buffer->audio_buffer.buffer_type = BUFFER_TYPE_RING_BUFFER;
 
 	/* return a pointer to allocated structure */

src/include/sof/audio/audio_buffer.h

@@ -15,6 +15,18 @@
 #define BUFFER_TYPE_LEGACY_BUFFER 1
 #define BUFFER_TYPE_RING_BUFFER 2
 
+/* forward def */
+struct sof_audio_buffer;
+
+struct audio_buffer_ops {
+	/**
+	 * @brief this method must free all structures allocated by buffer implementation
+	 *	  it must not free the buffer memory itself
+	 *	  OPTIONAL
+	 */
+	void (*free)(struct sof_audio_buffer *buffer);
+};
+
 /* base class for all buffers, all buffers must inherit from it */
 struct sof_audio_buffer {
 	CORE_CHECK_STRUCT_FIELD;
@@ -56,11 +68,7 @@ struct sof_audio_buffer {
 	struct sof_sink _sink_api;      /**< sink api handler */
 
 	/* virtual methods */
-	/**
-	 * @brief this method must free all structures allocated by buffer implementation
-	 *	  it must not free the buffer memory itself
-	 */
-	void (*free)(struct sof_audio_buffer *buffer);
+	const struct audio_buffer_ops *ops;
 };
 
 #if CONFIG_PIPELINE_2_0
@@ -200,10 +208,12 @@ static inline struct sof_audio_buffer *sof_audo_buffer_from_source(struct sof_so
 static inline
 void audio_buffer_init(struct sof_audio_buffer *buffer, uint32_t buffer_type, bool is_shared,
 		       const struct source_ops *source_ops, const struct sink_ops *sink_ops,
+		       const struct audio_buffer_ops *audio_buffer_ops,
 		       struct sof_audio_stream_params *audio_stream_params)
 {
 	CORE_CHECK_STRUCT_INIT(&buffer, is_shared);
 	buffer->buffer_type = buffer_type;
+	buffer->ops = audio_buffer_ops;
 	buffer->audio_stream_params = audio_stream_params;
 	source_init(audio_buffer_get_source(buffer), source_ops,
 		    audio_buffer_get_stream_params(buffer));