ACP->SYSMEM DMA happens at every I2S->SYSMEM period
completion. Thus, there is delay of x frames till
I2S->SYSMEM reaches a period length. This delay is
communicated to user space.
Signed-off-by: Akshu Agrawal <akshu.agrawal@xxxxxxx>
---
v2: moved reading of bytes transfered from I2S->ACP to get
more accurate delay information.
sound/soc/amd/acp-pcm-dma.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/sound/soc/amd/acp-pcm-dma.c b/sound/soc/amd/acp-pcm-dma.c
index 32f27c5..e359938 100644
--- a/sound/soc/amd/acp-pcm-dma.c
+++ b/sound/soc/amd/acp-pcm-dma.c
@@ -922,6 +922,10 @@ static int acp_dma_hw_params(struct snd_pcm_substream *substream,
rtd->destination = FROM_BLUETOOTH;
rtd->dma_dscr_idx_1 = CAPTURE_START_DMA_DESCR_CH10;
rtd->dma_dscr_idx_2 = CAPTURE_START_DMA_DESCR_CH11;
+ rtd->byte_cnt_high_reg_offset =
+ mmACP_I2S_BT_RECEIVE_BYTE_CNT_HIGH;
+ rtd->byte_cnt_low_reg_offset =
+ mmACP_I2S_BT_RECEIVE_BYTE_CNT_LOW;
rtd->dma_curr_dscr = mmACP_DMA_CUR_DSCR_11;
adata->capture_i2sbt_stream = substream;
break;
@@ -942,6 +946,10 @@ static int acp_dma_hw_params(struct snd_pcm_substream *substream,
rtd->destination = FROM_ACP_I2S_1;
rtd->dma_dscr_idx_1 = CAPTURE_START_DMA_DESCR_CH14;
rtd->dma_dscr_idx_2 = CAPTURE_START_DMA_DESCR_CH15;
+ rtd->byte_cnt_high_reg_offset =
+ mmACP_I2S_RECEIVED_BYTE_CNT_HIGH;
+ rtd->byte_cnt_low_reg_offset =
+ mmACP_I2S_RECEIVED_BYTE_CNT_LOW;
rtd->dma_curr_dscr = mmACP_DMA_CUR_DSCR_15;
adata->capture_i2ssp_stream = substream;
}
@@ -997,7 +1005,7 @@ static snd_pcm_uframes_t acp_dma_pointer(struct snd_pcm_substream *substream)
u32 pos = 0;
u64 bytescount = 0;
u16 dscr;
- u32 period_bytes;
+ u32 period_bytes, delay;
struct snd_pcm_runtime *runtime = substream->runtime;
struct audio_substream_data *rtd = runtime->private_data;
@@ -1012,6 +1020,11 @@ static snd_pcm_uframes_t acp_dma_pointer(struct snd_pcm_substream *substream)
pos = period_bytes;
else
pos = 0;
+ bytescount = acp_get_byte_count(rtd);
+ if (bytescount > rtd->bytescount)
+ bytescount -= rtd->bytescount;
+ delay = do_div(bytescount, period_bytes);
+ runtime->delay = bytes_to_frames(runtime, delay);
} else {
buffersize = frames_to_bytes(runtime, runtime->buffer_size);
bytescount = acp_get_byte_count(rtd);
--
1.9.1
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