[PATCH v4 11/15] soundwire: intel: add prepare support in sdw dai driver

Pierre-Louis Bossart
2019-12-13T05:04:44Z

From: Rander Wang <rander.wang@linux.intel.com>

The existing code does not expose a prepare operation, which is very
much needed to deal with underflow and resume operations.

Signed-off-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
---
drivers/soundwire/intel.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index adf06833af74..510b7f51826b 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -698,6 +698,21 @@ static int intel_hw_params(struct snd_pcm_substream *substream,
return ret;
}

+static int intel_prepare(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct sdw_cdns_dma_data *dma;
+
+ dma = snd_soc_dai_get_dma_data(dai, substream);
+ if (!dma) {
+ dev_err(dai->dev, "failed to get dma data in %s",
+ __func__);
+ return -EIO;
+ }
+
+ return sdw_prepare_stream(dma->stream);
+}
+
static int
intel_hw_free(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
{
@@ -744,6 +759,7 @@ static int intel_pdm_set_sdw_stream(struct snd_soc_dai *dai,

static const struct snd_soc_dai_ops intel_pcm_dai_ops = {
.hw_params = intel_hw_params,
+ .prepare = intel_prepare,
.hw_free = intel_hw_free,
.shutdown = intel_shutdown,
.set_sdw_stream = intel_pcm_set_sdw_stream,
@@ -751,6 +767,7 @@ static const struct snd_soc_dai_ops intel_pcm_dai_ops = {

static const struct snd_soc_dai_ops intel_pdm_dai_ops = {
.hw_params = intel_hw_params,
+ .prepare = intel_prepare,
.hw_free = intel_hw_free,
.shutdown = intel_shutdown,
.set_sdw_stream = intel_pdm_set_sdw_stream,
--
2.20.1