diff options
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/soc/soc-dmaengine-pcm.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/sound/soc/soc-dmaengine-pcm.c b/sound/soc/soc-dmaengine-pcm.c index 7c0877e3731c..2995334d8000 100644 --- a/sound/soc/soc-dmaengine-pcm.c +++ b/sound/soc/soc-dmaengine-pcm.c @@ -30,6 +30,7 @@ struct dmaengine_pcm_runtime_data { struct dma_chan *dma_chan; + dma_cookie_t cookie; unsigned int pos; @@ -153,7 +154,7 @@ static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream) desc->callback = dmaengine_pcm_dma_complete; desc->callback_param = substream; - dmaengine_submit(desc); + prtd->cookie = dmaengine_submit(desc); return 0; } @@ -213,6 +214,32 @@ snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue); +/** + * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation + * @substream: PCM substream + * + * This function can be used as the PCM pointer callback for dmaengine based PCM + * driver implementations. + */ +snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream) +{ + struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); + struct dma_tx_state state; + enum dma_status status; + unsigned int buf_size; + unsigned int pos = 0; + + status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state); + if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) { + buf_size = snd_pcm_lib_buffer_bytes(substream); + if (state.residue > 0 && state.residue <= buf_size) + pos = buf_size - state.residue; + } + + return bytes_to_frames(substream->runtime, pos); +} +EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer); + static int dmaengine_pcm_request_channel(struct dmaengine_pcm_runtime_data *prtd, dma_filter_fn filter_fn, void *filter_data) { |