audio: pipeline: do not propagate pipeline triggers for IPC4

One major difference in IPC4 versus IPC3 is that each pipeline
will get a separate SET_PIPELINE_STATE command. This is in stark
contrast to IPC3 where host sends STREAM_TRIG_START and firmware
is expected to propagate the state change to all connected
pipelines in the graph.

Change the code such that when pipeline component trigger is executed in
IPC4 build, propagation is stopped whenever we reach another pipeline.

This prevents bugs stemming from IPC3 related logic to propagate
pipeline triggers, interfering with IPC4 usages like in bug 8481.

To avoid false -ENODATA errors, drop IPC4 support for this capability.
The check added in commit b154132 ("ipc4: check pipeline priority
for error report") covers most cases, but this relies on host to send
the SET_PIPELINE_STATE calls in particular order. This unfortunately is
not a mandatory order to follow, so logic to check upstream pipeline
status to conclude downstream is in permanent -ENODATA state, is not as
solid as it is for IPC3. As this may lead to hard to debug errors (e.g.
when changing pipeline priorities in topologies which again affects the
order of the SET_PIPELINE_STATE), better to simply disable this feature
for IPC4.

Link: #8481
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>

src/audio/pipeline/pipeline-stream.c

@@ -47,6 +47,17 @@ pipeline_should_report_enodata_on_trigger(struct comp_dev *rsrc,
 	struct pipeline_data *ppl_data = ctx->comp_data;
 	struct comp_dev *pipe_source = ppl_data->start->pipeline->source_comp;
 
+	/* In IPC3, FW propagates triggers to connected pipelines, so
+	 * it can have determistic logic to conclude no data is
+	 * available.
+	 * In IPC4, host controls state of each pipeline separately,
+	 * so FW cannot reliably detect case of no data based on
+	 * observing state of src->pipeline here.
+	 */
+#if CONFIG_IPC_MAJOR_4
+	return false;
+#endif
+
 	/* only applies to capture pipelines */
 	if (dir != SOF_IPC_STREAM_CAPTURE)
 		return false;
@@ -388,8 +399,13 @@ static int pipeline_comp_trigger(struct comp_dev *current,
 
 	/* trigger should propagate to the connected pipelines,
 	 * which need to be scheduled together
+	 *
+	 * IPC4 has a SET_PIPELINE_STATE for each pipeline, so FW
+	 * should not propagate triggers on its own.
+	 * IPC3 has commands only for graph edges, so propagation is
+	 * needed in many cases.
 	 */
-	if (!is_single_ppl && !is_same_sched) {
+	if (!is_single_ppl && (!is_same_sched || IS_ENABLED(CONFIG_IPC_MAJOR_4))) {
 		pipe_dbg(current->pipeline,
 			 "pipeline_comp_trigger(), current is from another pipeline");