Replace the r_ptr == w_ptr check as it was racy on the completion of the host DMA preload. Better to check using the source component type.

Signed-off-by: Liam Girdwood liam.r.girdwood@linux.intel.com --- src/audio/dai.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/audio/dai.c b/src/audio/dai.c index 1afbc87..c50a274 100644 --- a/src/audio/dai.c +++ b/src/audio/dai.c @@ -492,27 +492,34 @@ static int dai_reset(struct comp_dev *dev) return 0; }

-/* the configuration of the upstream pipeline is unknown - * to the DAI so we have to check that the r_ptr != w_ptr for the - * DAI DMA buffer. This is not required for capture as the pipeline is - * run after the first period has been copied (i.e. r_ptr != w_ptr). +/* The playback source pipeline must be advanced by one period so that it + * does not write to the period that DMA is reading. The configuration of the + * upstream pipeline is unknown to the DAI but we can check if the source buffer + * is shared with another DMA engine (which preloads the buffer by one period) + * and only advance the write pointer when source component is not another + * DMA engine. */ static void dai_pointer_init(struct comp_dev *dev) { struct comp_buffer *dma_buffer; struct dai_data *dd = comp_get_drvdata(dev);

- /* advance w/r pointer by one period if equal at stream start */ + /* not reuquired for capture streams */ if (dev->params.direction == SOF_IPC_STREAM_PLAYBACK) { dma_buffer = list_first_item(&dev->bsource_list, struct comp_buffer, sink_list);

- if (dma_buffer->w_ptr != dma_buffer->r_ptr) - return; - - /* advance source pipeline w_ptr by one period - * this places pipeline w_ptr in period before DAI r_ptr */ - comp_update_buffer_produce(dma_buffer, dd->period_bytes); + switch (dma_buffer->source->comp.type) { + case SOF_COMP_HOST: + case SOF_COMP_SG_HOST: + /* buffer is preloaded and advanced by host DMA engine */ + break; + default: + /* advance source pipeline w_ptr by one period + * this places pipeline w_ptr in period before DAI r_ptr */ + comp_update_buffer_produce(dma_buffer, dd->period_bytes); + break; + } } }