Skip to content

audio: fix stream start offset arithmetic reported to the host #11287

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
lgirdwood merged 3 commits into from
Oct 9, 2026
Merged

audio: fix stream start offset arithmetic reported to the host #11287

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
d181485
pipeline: clamp latency accumulation against unsigned underflow
tmleman Oct 7, 2026
7641d8b
module: copier: compute stream start offset at 64-bit width
tmleman Oct 7, 2026
17272cf
module: copier: ignore out of order dai position on release
tmleman Oct 8, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
16 changes: 12 additions & 4 deletions src/audio/copier/copier.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -494,8 +494,8 @@ static int copier_comp_trigger(struct comp_dev *dev, int cmd)
}

buffer = comp_dev_get_first_data_producer(dai_copier);
pipe_reg.stream_start_offset = posn.dai_posn +
latency * audio_stream_period_bytes(&buffer->stream, dev->frames);
pipe_reg.stream_start_offset = posn.dai_posn + (uint64_t)latency *
audio_stream_period_bytes(&buffer->stream, dev->frames);
pipe_reg.stream_end_offset = 0;
mailbox_sw_regs_write(cd->pipeline_reg_offset, &pipe_reg, sizeof(pipe_reg));
} else if (cmd == COMP_TRIGGER_PAUSE) {
Expand All @@ -510,15 +510,23 @@ static int copier_comp_trigger(struct comp_dev *dev, int cmd)
pipe_reg.stream_start_offset = mailbox_sw_reg_read64(cd->pipeline_reg_offset);
pipe_reg.stream_end_offset = mailbox_sw_reg_read64(cd->pipeline_reg_offset +
sizeof(pipe_reg.stream_start_offset));
pipe_reg.stream_start_offset += posn.dai_posn - pipe_reg.stream_end_offset;

/* stream_end_offset was sampled from the dai position when the pipeline
* was paused, so the current position should be ahead of it. The value
* is read back from the host visible mailbox and cannot be trusted: a
* stale or out of order one would make the unsigned subtraction wrap
* and corrupt the offset reported to the host driver.
*/
if (posn.dai_posn > pipe_reg.stream_end_offset)
pipe_reg.stream_start_offset += posn.dai_posn - pipe_reg.stream_end_offset;
Comment on lines +520 to +521

if (list_is_empty(&dai_copier->bsource_list)) {
comp_err(dev, "No source buffer bound to dai_copier");
return -EINVAL;
}

buffer = comp_dev_get_first_data_producer(dai_copier);
pipe_reg.stream_start_offset += latency *
pipe_reg.stream_start_offset += (uint64_t)latency *
audio_stream_period_bytes(&buffer->stream, dev->frames);
mailbox_sw_regs_write(cd->pipeline_reg_offset, &pipe_reg.stream_start_offset,
sizeof(pipe_reg.stream_start_offset));
Expand Down
17 changes: 14 additions & 3 deletions src/audio/pipeline/pipeline-graph.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -699,9 +699,20 @@ struct comp_dev *pipeline_get_dai_comp_latency(uint32_t pipeline_id, uint32_t *l
if (ret < 0)
return NULL;

if (input_data && output_data && input_base_cfg.ibs && output_base_cfg.obs)
*latency += input_data / input_base_cfg.ibs -
output_data / output_base_cfg.obs;
if (input_data && output_data && input_base_cfg.ibs && output_base_cfg.obs) {
uint64_t in_blocks = input_data / input_base_cfg.ibs;
uint64_t out_blocks = output_data / output_base_cfg.obs;

/* The latency is a count of blocks buffered between the
* source and the sink and cannot be negative. The sink may
* legitimately lead the source, e.g. when the dai is started
* before the host because they are in different pipelines,
* so clamp instead of letting the unsigned subtraction wrap
* into a huge value.
*/
if (in_blocks > out_blocks)
*latency += in_blocks - out_blocks;
}

/* If the component doesn't have a sink buffer, it can be a dai. */
if (list_is_empty(&ipc_sink->cd->bsink_list))
Expand Down
Loading