[PATCH v2 2/2] media: chips-media: wave5: Check decoder runtime resume errors

[Guangshuo Li]

The decoder start_streaming, stop_streaming and device_run callbacks
resume the VPU before accessing hardware, but do not check the return
value from pm_runtime_resume_and_get().

If runtime resume fails, continuing can access the VPU while it remains
suspended. Since pm_runtime_resume_and_get() does not retain a runtime PM
usage reference on failure, the later unconditional
pm_runtime_put_autosuspend() can also drop an unmatched reference.

Check the return value in all three callbacks. Return queued buffers as
required by vb2 when start_streaming fails, clean up buffers without
touching hardware when stop_streaming fails, and finish the current
mem2mem job when device_run cannot resume.

Only call pm_runtime_put_autosuspend() after a successful runtime
resume.

Fixes: 2092b3833487 ("media: chips-media: wave5: Support runtime suspend/resume")
Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
---
 .../chips-media/wave5/wave5-vpu-dec.c         | 36 +++++++++++++++++--
 1 file changed, 33 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c b/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c
index 03d108b808ba..bb59bc962603 100644
--- a/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c
+++ b/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c
@@ -1380,7 +1380,11 @@ static int wave5_vpu_dec_start_streaming(struct vb2_queue *q, unsigned int count
 	int ret = 0;
 
 	dev_dbg(inst->dev->dev, "%s: type: %u\n", __func__, q->type);
-	pm_runtime_resume_and_get(inst->dev->dev);
+	ret = pm_runtime_resume_and_get(inst->dev->dev);
+	if (ret < 0) {
+		wave5_return_bufs(q, VB2_BUF_STATE_QUEUED);
+		return ret;
+	}
 
 	v4l2_m2m_update_start_streaming_state(m2m_ctx, q);
 
@@ -1544,9 +1548,29 @@ static void wave5_vpu_dec_stop_streaming(struct vb2_queue *q)
 	struct v4l2_m2m_ctx *m2m_ctx = inst->v4l2_fh.m2m_ctx;
 
 	bool check_cmd = TRUE;
+	int ret;
 
 	dev_dbg(inst->dev->dev, "%s: type: %u\n", __func__, q->type);
-	pm_runtime_resume_and_get(inst->dev->dev);
+	ret = pm_runtime_resume_and_get(inst->dev->dev);
+	if (ret < 0) {
+		struct vpu_src_buffer *vpu_buf;
+
+		v4l2_m2m_update_stop_streaming_state(m2m_ctx, q);
+
+		if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
+			inst->retry = false;
+			inst->queuing_num = 0;
+			while ((vpu_buf = inst_src_buf_remove(inst)) != NULL)
+				;
+			inst->eos = false;
+		}
+
+		wave5_return_bufs(q, VB2_BUF_STATE_ERROR);
+		inst->empty_queue = false;
+		inst->sent_eos = false;
+		return;
+	}
+
 	inst->empty_queue = true;
 	while (check_cmd) {
 		struct queue_status_info q_status;
@@ -1659,7 +1683,13 @@ static void wave5_vpu_dec_device_run(void *priv)
 	int ret = 0;
 
 	dev_dbg(inst->dev->dev, "%s: Fill the ring buffer with new bitstream data", __func__);
-	pm_runtime_resume_and_get(inst->dev->dev);
+
+	ret = pm_runtime_resume_and_get(inst->dev->dev);
+	if (ret < 0) {
+		v4l2_m2m_job_finish(inst->v4l2_m2m_dev, m2m_ctx);
+		return;
+	}
+
 	if (!inst->retry) {
 		ret = fill_ringbuffer(inst);
 		if (ret < 0) {
-- 
2.43.0