@@ -251,6 +251,44 @@ static inline short MULTI_DIV_short(short a, unsigned int b, int swap)
} \
} \
} while (0)
+
+#define CONVERT_AREA_S24_LE() do { \
+ unsigned int ch, fr; \
+ int *src, *dst; \
+ int tmp; \
+ for (ch = 0; ch < channels; ch++) { \
+ src_area = &src_areas[ch]; \
+ dst_area = &dst_areas[ch]; \
+ src = snd_pcm_channel_area_addr(src_area, src_offset); \
+ dst = snd_pcm_channel_area_addr(dst_area, dst_offset); \
+ src_step = snd_pcm_channel_area_step(src_area) \
+ / sizeof(int); \
+ dst_step = snd_pcm_channel_area_step(dst_area) \
+ / sizeof(int); \
+ GET_VOL_SCALE; \
+ fr = frames; \
+ if (! vol_scale) { \
+ while (fr--) { \
+ *dst = 0; \
+ dst += dst_step; \
+ } \
+ } else if (vol_scale == 0xffff) { \
+ while (fr--) { \
+ *dst = *src; \
+ src += dst_step; \
+ dst += src_step; \
+ } \
+ } else { \
+ while (fr--) { \
+ tmp = *src << 8; \
+ tmp = (signed int) tmp >> 8; \
+ *dst = MULTI_DIV_24(tmp, vol_scale); \
+ src += dst_step; \
+ dst += src_step; \
+ } \
+ } \
+ } \
+} while (0)
#define GET_VOL_SCALE \
switch (ch) { \
@@ -315,6 +353,10 @@ static void softvol_convert_stereo_vol(snd_pcm_softvol_t *svol,
CONVERT_AREA(int,
!snd_pcm_format_cpu_endian(svol->sformat));
break;
+ case SND_PCM_FORMAT_S24_LE:
+ /* 24bit samples */
+ CONVERT_AREA_S24_LE();
+ break;
case SND_PCM_FORMAT_S24_3LE:
CONVERT_AREA_S24_3LE();
break;
@@ -366,6 +408,10 @@ static void softvol_convert_mono_vol(snd_pcm_softvol_t *svol,
CONVERT_AREA(int,
!snd_pcm_format_cpu_endian(svol->sformat));
break;
+ case SND_PCM_FORMAT_S24_LE:
+ /* 24bit samples */
+ CONVERT_AREA_S24_LE();
+ break;
case SND_PCM_FORMAT_S24_3LE:
CONVERT_AREA_S24_3LE();
break;
@@ -422,6 +468,7 @@ static int snd_pcm_softvol_hw_refine_cprepare(snd_pcm_t *pcm,
{
(1ULL << SND_PCM_FORMAT_S16_LE) |
(1ULL << SND_PCM_FORMAT_S16_BE) |
+ (1ULL << SND_PCM_FORMAT_S24_LE) |
(1ULL << SND_PCM_FORMAT_S32_LE) |
(1ULL << SND_PCM_FORMAT_S32_BE),
(1ULL << (SND_PCM_FORMAT_S24_3LE - 32))
@@ -577,10 +624,11 @@ static int snd_pcm_softvol_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * param
if (slave->format != SND_PCM_FORMAT_S16_LE &&
slave->format != SND_PCM_FORMAT_S16_BE &&
slave->format != SND_PCM_FORMAT_S24_3LE &&
+ slave->format != SND_PCM_FORMAT_S24_LE &&
slave->format != SND_PCM_FORMAT_S32_LE &&
slave->format != SND_PCM_FORMAT_S32_BE) {
- SNDERR("softvol supports only S16_LE, S16_BE, S24_3LE, S32_LE "
- " or S32_BE");
+ SNDERR("softvol supports only S16_LE, S16_BE, S24_LE, S24_3LE, "
+ "S32_LE or S32_BE");
return -EINVAL;
}
svol->sformat = slave->format;
@@ -863,6 +911,7 @@ int snd_pcm_softvol_open(snd_pcm_t **pcmp, const char *name,
sformat != SND_PCM_FORMAT_S16_LE &&
sformat != SND_PCM_FORMAT_S16_BE &&
sformat != SND_PCM_FORMAT_S24_3LE &&
+ sformat != SND_PCM_FORMAT_S24_LE &&
sformat != SND_PCM_FORMAT_S32_LE &&
sformat != SND_PCM_FORMAT_S32_BE)
return -EINVAL;
@@ -1082,9 +1131,10 @@ int _snd_pcm_softvol_open(snd_pcm_t **pcmp, const char *name,
sformat != SND_PCM_FORMAT_S16_LE &&
sformat != SND_PCM_FORMAT_S16_BE &&
sformat != SND_PCM_FORMAT_S24_3LE &&
+ sformat != SND_PCM_FORMAT_S24_LE &&
sformat != SND_PCM_FORMAT_S32_LE &&
sformat != SND_PCM_FORMAT_S32_BE) {
- SNDERR("only S16_LE, S16_BE, S24_3LE, S32_LE or S32_BE format is supported");
+ SNDERR("only S16_LE, S16_BE, S24_LE, S24_3LE, S32_LE or S32_BE format is supported");
snd_config_delete(sconf);
return -EINVAL;
}
Tested with the Wolfson WM8524 DAC on a i.MX6UL board and the following ALSA configuration file using the pcm test utility from alsa-lib: """ $ cat /etc/asound.conf pcm.!default { type plug slave.pcm "softvol" } pcm.softvol { type softvol slave { pcm "hw:0" } control { name "Master" card 0 } } ctl.!default { type hw card 0 } ctl.softvol { type hw card 0 } $ pcm -D softvol -o S24_LE -c 2 -r 48000 """ The data in the Synchronous Audio Interface (SAI) of the i.MX6UL is aligned the following way: """ 31 30 29 28 | 27 26 25 24 | 23 22 21 20 | .. | 3 2 1 0 ## ## ## ## ## ## ## ## [ DATA[23:0] ] """ Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks> --- v2: * add CONVERT_AREA_S24_LE algorithm instead of using the same one as S32_LE --- src/pcm/pcm_softvol.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 53 insertions(+), 3 deletions(-)