ASoC: dwc: Ensure FIFOs are flushed to prevent channel swap

Flush the FIFOs when the stream is prepared for use.  This avoids
an inadvertent swapping of the left/right channels if the FIFOs are
not empty at startup.

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This commit is contained in:
Andrew Jackson 2014-12-19 16:18:05 +00:00 committed by Mark Brown
parent 97bf6af1f9
commit 3475c3d034
1 changed files with 14 additions and 0 deletions

View File

@ -263,6 +263,19 @@ static void dw_i2s_shutdown(struct snd_pcm_substream *substream,
snd_soc_dai_set_dma_data(dai, substream, NULL);
}
static int dw_i2s_prepare(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
i2s_write_reg(dev->i2s_base, TXFFR, 1);
else
i2s_write_reg(dev->i2s_base, RXFFR, 1);
return 0;
}
static int dw_i2s_trigger(struct snd_pcm_substream *substream,
int cmd, struct snd_soc_dai *dai)
{
@ -294,6 +307,7 @@ static struct snd_soc_dai_ops dw_i2s_dai_ops = {
.startup = dw_i2s_startup,
.shutdown = dw_i2s_shutdown,
.hw_params = dw_i2s_hw_params,
.prepare = dw_i2s_prepare,
.trigger = dw_i2s_trigger,
};