The dma channel has been requested by Back-End cpu dai driver already.
If fsl_asrc_dma requests dma chan with same dma:tx symlink, then
there will be below warning with SDMA.
[ 48.174236] fsl-esai-dai 2024000.esai: Cannot create DMA dma:tx symlink
or with EDMA the request operation will fail for EDMA channel
can only be requested once.
So If we can reuse the dma channel of Back-End, then the issue can be
fixed.
In order to get the dma channel which is already requested in Back-End.
we use the exported two functions (snd_soc_lookup_component_nolocked
and soc_component_to_pcm). If we can get the dma channel, then reuse it,
if can't, then request a new one.
Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
---
sound/soc/fsl/fsl_asrc_common.h | 2 ++
sound/soc/fsl/fsl_asrc_dma.c | 52 +++++++++++++++++++++++++--------
2 files changed, 42 insertions(+), 12 deletions(-)
diff --git a/sound/soc/fsl/fsl_asrc_common.h b/sound/soc/fsl/fsl_asrc_common.h
index 77665b15c8db..09512bc79b80 100644
--- a/sound/soc/fsl/fsl_asrc_common.h
+++ b/sound/soc/fsl/fsl_asrc_common.h
@@ -32,6 +32,7 @@ enum asrc_pair_index {
* @dma_chan: inputer and output DMA channels
* @dma_data: private dma data
* @pos: hardware pointer position
+ * @req_dma_chan_dev_to_dev: flag for release dev_to_dev chan
* @private: pair private area
*/
struct fsl_asrc_pair {
@@ -45,6 +46,7 @@ struct fsl_asrc_pair {
struct dma_chan *dma_chan[2];
struct imx_dma_data dma_data;
unsigned int pos;
+ bool req_dma_chan_dev_to_dev;
void *private;
};
diff --git a/sound/soc/fsl/fsl_asrc_dma.c b/sound/soc/fsl/fsl_asrc_dma.c
index d6a3fc5f87e5..5ecb77d466d3 100644
--- a/sound/soc/fsl/fsl_asrc_dma.c
+++ b/sound/soc/fsl/fsl_asrc_dma.c
@@ -133,6 +133,7 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
struct snd_dmaengine_dai_dma_data *dma_params_fe = NULL;
struct snd_dmaengine_dai_dma_data *dma_params_be = NULL;
+ struct dma_chan *tmp_chan = NULL, *tmp_chan_new = NULL;
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
struct fsl_asrc *asrc = pair->asrc;
@@ -142,7 +143,6 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
int stream = substream->stream;
struct imx_dma_data *tmp_data;
struct snd_soc_dpcm *dpcm;
- struct dma_chan *tmp_chan;
struct device *dev_be;
u8 dir = tx ? OUT : IN;
dma_cap_mask_t mask;
@@ -152,6 +152,7 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
for_each_dpcm_be(rtd, stream, dpcm) {
struct snd_soc_pcm_runtime *be = dpcm->be;
struct snd_pcm_substream *substream_be;
+ struct snd_soc_component *component_be;
struct snd_soc_dai *dai = asoc_rtd_to_cpu(be, 0);
if (dpcm->fe != rtd)
@@ -160,6 +161,9 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
substream_be = snd_soc_dpcm_get_substream(be, stream);
dma_params_be = snd_soc_dai_get_dma_data(dai, substream_be);
dev_be = dai->dev;
+ component_be = snd_soc_lookup_component_nolocked(dev_be, SND_DMAENGINE_PCM_DRV_NAME);
+ if (component_be)
+ tmp_chan = soc_component_to_pcm(component_be)->chan[substream->stream];
break;
}
@@ -205,10 +209,14 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
*/
if (!asrc->use_edma) {
/* Get DMA request of Back-End */
- tmp_chan = dma_request_slave_channel(dev_be, tx ? "tx" : "rx");
+ if (!tmp_chan) {
+ tmp_chan_new = dma_request_slave_channel(dev_be, tx ? "tx" : "rx");
+ tmp_chan = tmp_chan_new;
+ }
tmp_data = tmp_chan->private;
pair->dma_data.dma_request = tmp_data->dma_request;
- dma_release_channel(tmp_chan);
+ if (tmp_chan_new)
+ dma_release_channel(tmp_chan_new);
/* Get DMA request of Front-End */
tmp_chan = asrc->get_dma_channel(pair, dir);
@@ -220,9 +228,26 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
pair->dma_chan[dir] =
dma_request_channel(mask, filter, &pair->dma_data);
+ pair->req_dma_chan_dev_to_dev = true;
} else {
- pair->dma_chan[dir] =
- asrc->get_dma_channel(pair, dir);
+ /*
+ * With EDMA, there is two dma channels can be used for p2p,
+ * one is from ASRC, one is from another peripheral
+ * (ESAI or SAI). Previously we select the dma channel of ASRC,
+ * but find an issue for ideal ratio case, there is no control
+ * for data copy speed, the speed is faster than sample
+ * frequency.
+ *
+ * So we switch to use dma channel of peripheral (ESAI or SAI),
+ * that copy speed of DMA is controlled by data consumption
+ * speed in the peripheral FIFO.
+ */
+ pair->req_dma_chan_dev_to_dev = false;
+ pair->dma_chan[dir] = tmp_chan;
+ if (!pair->dma_chan[dir]) {
+ pair->dma_chan[dir] = dma_request_slave_channel(dev_be, tx ? "tx" : "rx");
+ pair->req_dma_chan_dev_to_dev = true;
+ }
}
if (!pair->dma_chan[dir]) {
@@ -261,7 +286,8 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
if (ret) {
dev_err(dev, "failed to config DMA channel for Back-End\n");
- dma_release_channel(pair->dma_chan[dir]);
+ if (pair->req_dma_chan_dev_to_dev)
+ dma_release_channel(pair->dma_chan[dir]);
return ret;
}
@@ -273,19 +299,21 @@ static int fsl_asrc_dma_hw_params(struct snd_soc_component *component,
static int fsl_asrc_dma_hw_free(struct snd_soc_component *component,
struct snd_pcm_substream *substream)
{
+ bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
+ u8 dir = tx ? OUT : IN;
snd_pcm_set_runtime_buffer(substream, NULL);
- if (pair->dma_chan[IN])
- dma_release_channel(pair->dma_chan[IN]);
+ if (pair->dma_chan[!dir])
+ dma_release_channel(pair->dma_chan[!dir]);
- if (pair->dma_chan[OUT])
- dma_release_channel(pair->dma_chan[OUT]);
+ if (pair->dma_chan[dir] && pair->req_dma_chan_dev_to_dev)
+ dma_release_channel(pair->dma_chan[dir]);
- pair->dma_chan[IN] = NULL;
- pair->dma_chan[OUT] = NULL;
+ pair->dma_chan[!dir] = NULL;
+ pair->dma_chan[dir] = NULL;
return 0;
}
--
2.21.0
