[PATCH 5.4 015/222] ASoC: stm32: dfsdm: fix 16 bits record

[Greg Kroah-Hartman]

From: Olivier Moysan <olivier.moysan@xxxxxx>

commit 8e55ea19125b65cffe42747359af99d545e85f2f upstream.

In stm32_afsdm_pcm_cb function, the transfer size is provided in bytes.
However, samples are copied as 16 bits words from iio buffer.
Divide by two the transfer size, to copy the right number of samples.

Fixes: 1e7f6e1c69f0 ("ASoC: stm32: dfsdm: add 16 bits audio record support")

Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxx>
Link: https://lore.kernel.org/r/20200110131131.3191-1-olivier.moysan@xxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 sound/soc/stm/stm32_adfsdm.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/sound/soc/stm/stm32_adfsdm.c
+++ b/sound/soc/stm/stm32_adfsdm.c
@@ -153,13 +153,13 @@ static const struct snd_soc_component_dr
 	.name = "stm32_dfsdm_audio",
 };
 
-static void memcpy_32to16(void *dest, const void *src, size_t n)
+static void stm32_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--) {
+	for (i = n >> 1; i > 0; i--) {
 		*d++ = *s++;
 		s++;
 	}
@@ -186,8 +186,8 @@ static int stm32_afsdm_pcm_cb(const void
 
 	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);
+			stm32_memcpy_32to16(&pcm_buff[priv->pos], src_buff,
+					    buff_size - priv->pos);
 		else
 			memcpy(&pcm_buff[priv->pos], src_buff,
 			       buff_size - priv->pos);
@@ -196,8 +196,8 @@ static int stm32_afsdm_pcm_cb(const void
 	}
 
 	if (format == SNDRV_PCM_FORMAT_S16_LE)
-		memcpy_32to16(&pcm_buff[priv->pos],
-			      &src_buff[src_size - cur_size], cur_size);
+		stm32_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);