[PATCH] ASoC: stm32: dfsdm: add 16 bits audio record support

From: Olivier Moysan
Date: Wed Jun 19 2019 - 07:40:02 EST


Add support of audio 16 bits format record to STM32
DFSDM driver.

Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/stm/stm32_adfsdm.c | 49 ++++++++++++++++++++++++++++--------
1 file changed, 39 insertions(+), 10 deletions(-)

diff --git a/sound/soc/stm/stm32_adfsdm.c b/sound/soc/stm/stm32_adfsdm.c
index cc517e007039..3c9a9deec9af 100644
--- a/sound/soc/stm/stm32_adfsdm.c
+++ b/sound/soc/stm/stm32_adfsdm.c
@@ -45,7 +45,7 @@ struct stm32_adfsdm_priv {
static const struct snd_pcm_hardware stm32_adfsdm_pcm_hw = {
.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_PAUSE,
- .formats = SNDRV_PCM_FMTBIT_S32_LE,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,

.rate_min = 8000,
.rate_max = 32000,
@@ -141,7 +141,8 @@ static const struct snd_soc_dai_driver stm32_adfsdm_dai = {
.capture = {
.channels_min = 1,
.channels_max = 1,
- .formats = SNDRV_PCM_FMTBIT_S32_LE,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE |
+ SNDRV_PCM_FMTBIT_S32_LE,
.rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 |
SNDRV_PCM_RATE_32000),
},
@@ -152,30 +153,58 @@ static const struct snd_soc_component_driver stm32_adfsdm_dai_component = {
.name = "stm32_dfsdm_audio",
};

+static void memcpy_32to16(void *dest, const void *src, size_t n)
+{
+ unsigned int i = 0;
+ u16 *d = (u16 *)dest, *s = (u16 *)src;
+
+ s++;
+ for (i = n; i > 0; i--) {
+ *d++ = *s++;
+ s++;
+ }
+}
+
static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private)
{
struct stm32_adfsdm_priv *priv = private;
struct snd_soc_pcm_runtime *rtd = priv->substream->private_data;
u8 *pcm_buff = priv->pcm_buff;
u8 *src_buff = (u8 *)data;
- unsigned int buff_size = snd_pcm_lib_buffer_bytes(priv->substream);
- unsigned int period_size = snd_pcm_lib_period_bytes(priv->substream);
unsigned int old_pos = priv->pos;
- unsigned int cur_size = size;
+ size_t buff_size = snd_pcm_lib_buffer_bytes(priv->substream);
+ size_t period_size = snd_pcm_lib_period_bytes(priv->substream);
+ size_t cur_size, src_size = size;
+ snd_pcm_format_t format = priv->substream->runtime->format;
+
+ if (format == SNDRV_PCM_FORMAT_S16_LE)
+ src_size >>= 1;
+ cur_size = src_size;

dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n",
- __func__, &pcm_buff[priv->pos], priv->pos, size);
+ __func__, &pcm_buff[priv->pos], priv->pos, src_size);

- if ((priv->pos + size) > buff_size) {
- memcpy(&pcm_buff[priv->pos], src_buff, buff_size - priv->pos);
+ if ((priv->pos + src_size) > buff_size) {
+ if (format == SNDRV_PCM_FORMAT_S16_LE)
+ memcpy_32to16(&pcm_buff[priv->pos], src_buff,
+ buff_size - priv->pos);
+ else
+ memcpy(&pcm_buff[priv->pos], src_buff,
+ buff_size - priv->pos);
cur_size -= buff_size - priv->pos;
priv->pos = 0;
}

- memcpy(&pcm_buff[priv->pos], &src_buff[size - cur_size], cur_size);
+ if (format == SNDRV_PCM_FORMAT_S16_LE)
+ memcpy_32to16(&pcm_buff[priv->pos],
+ &src_buff[src_size - cur_size], cur_size);
+ else
+ memcpy(&pcm_buff[priv->pos], &src_buff[src_size - cur_size],
+ cur_size);
+
priv->pos = (priv->pos + cur_size) % buff_size;

- if (cur_size != size || (old_pos && (old_pos % period_size < size)))
+ if (cur_size != src_size || (old_pos && (old_pos % period_size < size)))
snd_pcm_period_elapsed(priv->substream);

return 0;
--
2.20.1