[PATCH 6.1 0953/1191] ASoC: qcom: q6apm: keep the graph start count in sync with the DSP

6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jorijn van der Graaf <jorijnvdgraaf@catcrafts.net>

[ Upstream commit daa7ffd765ae67a83e77dae32c66ce2d6d995d19 ]

q6apm_graph_start() increments start_count even when APM_CMD_GRAPH_START
fails, leaving the graph counted as running while the DSP never started
it. A later start - a retried prepare, or a resume after a failed start -
then finds a non-zero count, skips the command and returns success with
no data flowing.

Count the graph only once the DSP has accepted the start. The count then
stays at zero for a graph that never started, so also stop decrementing
below zero in q6apm_graph_stop(): the compressed free path stops
unconditionally, and a negative count would make the next start skip the
command in the same way.

Fixes: 5477518b8a0e ("ASoC: qdsp6: audioreach: add q6apm support")
Assisted-by: Claude:claude-opus-5
Signed-off-by: Jorijn van der Graaf <jorijnvdgraaf@catcrafts.net>
Link: https://patch.msgid.link/20260726211226.94059-1-jorijnvdgraaf@catcrafts.net (local)
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/soc/qcom/qdsp6/q6apm.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/sound/soc/qcom/qdsp6/q6apm.c b/sound/soc/qcom/qdsp6/q6apm.c
index 586ee4c7ff6d8..f9ee8bbe35f25 100644
--- a/sound/soc/qcom/qdsp6/q6apm.c
+++ b/sound/soc/qcom/qdsp6/q6apm.c

@@ -682,14 +682,17 @@ EXPORT_SYMBOL_GPL(q6apm_graph_prepare);
 int q6apm_graph_start(struct q6apm_graph *graph)
 {
 	struct audioreach_graph *ar_graph = graph->ar_graph;
-	int ret = 0;
+	int ret;
 
-	if (ar_graph->start_count == 0)
+	if (ar_graph->start_count == 0) {
 		ret = audioreach_graph_mgmt_cmd(ar_graph, APM_CMD_GRAPH_START);
+		if (ret)
+			return ret;
+	}
 
 	ar_graph->start_count++;
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(q6apm_graph_start);
 

@@ -697,6 +700,9 @@ int q6apm_graph_stop(struct q6apm_graph *graph)
 {
 	struct audioreach_graph *ar_graph = graph->ar_graph;
 
+	if (ar_graph->start_count == 0)
+		return 0;
+
 	if (--ar_graph->start_count > 0)
 		return 0;
 

-- 
2.53.0