ASoC: AMD: Reset bytescount when starting transaction

The pointer() callback gets its value by reading the I2S BYTE_COUNT
register.  This is a 64-bit runnning transaction counter. If a
transaction was aborted in the middle of a sample buffer, the counter will
stop counting on a number divisible by the buffer size.  Since we actually
use it as a pointer into an aligned buffer, however, we do want to ensure
that it always starts at a number divisible by the buffer size when
starting a transaction, hence we reset it whenever starting a transaction.

To accomplish this, it wasn't necessary to zero bytescount at the
termination of each transaction, so remove this unnecessary code.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/amd/acp-pcm-dma.c b/sound/soc/amd/acp-pcm-dma.c
index cd4d252..ab60129 100644 (file)
--- a/sound/soc/amd/acp-pcm-dma.c
+++ b/sound/soc/amd/acp-pcm-dma.c
@@ -1013,7 +1013,6 @@ static int acp_dma_prepare(struct snd_pcm_substream *substream)
 static int acp_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 {
        int ret;
-       u64 bytescount = 0;
 
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct audio_substream_data *rtd = runtime->private_data;
@@ -1024,9 +1023,7 @@ static int acp_dma_trigger(struct snd_pcm_substream *substream, int cmd)
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
        case SNDRV_PCM_TRIGGER_RESUME:
-               bytescount = acp_get_byte_count(rtd);
-               if (rtd->bytescount == 0)
-                       rtd->bytescount = bytescount;
+               rtd->bytescount = acp_get_byte_count(rtd);
                if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
                        acp_dma_start(rtd->acp_mmio, rtd->ch1);
                        acp_dma_start(rtd->acp_mmio, rtd->ch2);
@@ -1053,7 +1050,6 @@ static int acp_dma_trigger(struct snd_pcm_substream *substream, int cmd)
        case SNDRV_PCM_TRIGGER_SUSPEND:
                acp_dma_stop(rtd->acp_mmio, rtd->ch2);
                ret = acp_dma_stop(rtd->acp_mmio, rtd->ch1);
-               rtd->bytescount = 0;
                break;
        default:
                ret = -EINVAL;