/* This field need to be the first */
snd_pcm_plugin_t plug;
snd_pcm_format_t sformat;
+ unsigned int cchannels;
snd_ctl_t *ctl;
snd_ctl_elem_value_t elem;
+ unsigned int cur_vol[2];
unsigned int max_val;
double min_dB;
unsigned short *dB_value;
#define PRESET_MIN_DB -48.0
static unsigned short preset_dB_value[PRESET_RESOLUTION] = {
- 0x0000, 0x0930, 0x094f, 0x096e, 0x098e, 0x09af, 0x09cf, 0x09f0,
- 0x0a12, 0x0a34, 0x0a56, 0x0a79, 0x0a9d, 0x0ac0, 0x0ae5, 0x0b0a,
- 0x0b2f, 0x0b55, 0x0b7b, 0x0ba2, 0x0bc9, 0x0bf1, 0x0c19, 0x0c42,
- 0x0c6b, 0x0c95, 0x0cc0, 0x0ceb, 0x0d16, 0x0d42, 0x0d6f, 0x0d9c,
- 0x0dca, 0x0df9, 0x0e28, 0x0e58, 0x0e88, 0x0eb9, 0x0eeb, 0x0f1d,
- 0x0f51, 0x0f84, 0x0fb9, 0x0fee, 0x1023, 0x105a, 0x1091, 0x10c9,
- 0x1102, 0x113b, 0x1175, 0x11b0, 0x11ec, 0x1228, 0x1266, 0x12a4,
- 0x12e3, 0x1322, 0x1363, 0x13a5, 0x13e7, 0x142a, 0x146e, 0x14b3,
- 0x14f9, 0x1540, 0x1587, 0x15d0, 0x161a, 0x1664, 0x16b0, 0x16fd,
- 0x174a, 0x1799, 0x17e8, 0x1839, 0x188b, 0x18de, 0x1932, 0x1987,
- 0x19dd, 0x1a34, 0x1a8d, 0x1ae6, 0x1b41, 0x1b9d, 0x1bfa, 0x1c59,
- 0x1cb8, 0x1d19, 0x1d7c, 0x1ddf, 0x1e44, 0x1eaa, 0x1f12, 0x1f7a,
- 0x1fe5, 0x2050, 0x20bd, 0x212c, 0x219c, 0x220d, 0x2280, 0x22f5,
- 0x236b, 0x23e2, 0x245b, 0x24d6, 0x2553, 0x25d1, 0x2650, 0x26d2,
- 0x2755, 0x27d9, 0x2860, 0x28e8, 0x2972, 0x29fe, 0x2a8c, 0x2b1b,
- 0x2bad, 0x2c40, 0x2cd6, 0x2d6d, 0x2e06, 0x2ea2, 0x2f3f, 0x2fdf,
- 0x3080, 0x3124, 0x31ca, 0x3272, 0x331c, 0x33c9, 0x3477, 0x3529,
- 0x35dc, 0x3692, 0x374a, 0x3805, 0x38c2, 0x3981, 0x3a43, 0x3b08,
- 0x3bcf, 0x3c99, 0x3d66, 0x3e35, 0x3f07, 0x3fdc, 0x40b3, 0x418e,
- 0x426b, 0x434b, 0x442e, 0x4514, 0x45fe, 0x46ea, 0x47d9, 0x48cc,
- 0x49c2, 0x4aba, 0x4bb7, 0x4cb6, 0x4db9, 0x4ec0, 0x4fc9, 0x50d7,
- 0x51e8, 0x52fc, 0x5414, 0x5530, 0x564f, 0x5773, 0x589a, 0x59c5,
- 0x5af4, 0x5c27, 0x5d5e, 0x5e99, 0x5fd9, 0x611c, 0x6264, 0x63b0,
- 0x6501, 0x6655, 0x67af, 0x690d, 0x6a6f, 0x6bd7, 0x6d43, 0x6eb3,
- 0x7029, 0x71a4, 0x7323, 0x74a8, 0x7632, 0x77c1, 0x7955, 0x7aee,
- 0x7c8d, 0x7e32, 0x7fdc, 0x818b, 0x8341, 0x84fc, 0x86bc, 0x8883,
- 0x8a50, 0x8c23, 0x8dfc, 0x8fdb, 0x91c1, 0x93ad, 0x959f, 0x9798,
- 0x9998, 0x9b9e, 0x9dac, 0x9fc0, 0xa1db, 0xa3fd, 0xa627, 0xa858,
- 0xaa90, 0xacd0, 0xaf17, 0xb166, 0xb3bd, 0xb61c, 0xb882, 0xbaf1,
- 0xbd68, 0xbfe7, 0xc26f, 0xc4ff, 0xc798, 0xca3a, 0xcce5, 0xcf98,
- 0xd255, 0xd51b, 0xd7ea, 0xdac3, 0xdda5, 0xe092, 0xe388, 0xe688,
- 0xe992, 0xeca6, 0xefc5, 0xf2ee, 0xf622, 0xf961, 0xfcab, 0xffff,
+ 0x0000, 0x0104, 0x010a, 0x0110, 0x0116, 0x011c, 0x0122, 0x0129,
+ 0x012f, 0x0136, 0x013d, 0x0144, 0x014b, 0x0152, 0x015a, 0x0161,
+ 0x0169, 0x0171, 0x0179, 0x0181, 0x018a, 0x0193, 0x019c, 0x01a5,
+ 0x01ae, 0x01b7, 0x01c1, 0x01cb, 0x01d5, 0x01df, 0x01ea, 0x01f5,
+ 0x0200, 0x020b, 0x0216, 0x0222, 0x022e, 0x023b, 0x0247, 0x0254,
+ 0x0261, 0x026e, 0x027c, 0x028a, 0x0298, 0x02a7, 0x02b6, 0x02c5,
+ 0x02d5, 0x02e5, 0x02f5, 0x0306, 0x0317, 0x0328, 0x033a, 0x034c,
+ 0x035f, 0x0372, 0x0385, 0x0399, 0x03ad, 0x03c2, 0x03d7, 0x03ed,
+ 0x0403, 0x041a, 0x0431, 0x0448, 0x0460, 0x0479, 0x0492, 0x04ac,
+ 0x04c6, 0x04e1, 0x04fd, 0x0519, 0x0535, 0x0553, 0x0571, 0x058f,
+ 0x05af, 0x05cf, 0x05ef, 0x0611, 0x0633, 0x0656, 0x067a, 0x069e,
+ 0x06c3, 0x06ea, 0x0710, 0x0738, 0x0761, 0x078a, 0x07b5, 0x07e0,
+ 0x080d, 0x083a, 0x0868, 0x0898, 0x08c8, 0x08fa, 0x092c, 0x0960,
+ 0x0995, 0x09cb, 0x0a02, 0x0a3a, 0x0a74, 0x0aae, 0x0aeb, 0x0b28,
+ 0x0b67, 0x0ba7, 0x0be9, 0x0c2c, 0x0c70, 0x0cb6, 0x0cfe, 0x0d47,
+ 0x0d92, 0x0dde, 0x0e2d, 0x0e7c, 0x0ece, 0x0f21, 0x0f76, 0x0fce,
+ 0x1027, 0x1081, 0x10de, 0x113d, 0x119f, 0x1202, 0x1267, 0x12cf,
+ 0x1339, 0x13a5, 0x1414, 0x1485, 0x14f8, 0x156e, 0x15e7, 0x1662,
+ 0x16e0, 0x1761, 0x17e5, 0x186b, 0x18f5, 0x1981, 0x1a11, 0x1aa4,
+ 0x1b3a, 0x1bd3, 0x1c70, 0x1d10, 0x1db4, 0x1e5b, 0x1f06, 0x1fb4,
+ 0x2067, 0x211d, 0x21d8, 0x2297, 0x2359, 0x2420, 0x24ec, 0x25bc,
+ 0x2690, 0x2769, 0x2847, 0x292a, 0x2a12, 0x2aff, 0x2bf1, 0x2ce8,
+ 0x2de5, 0x2ee8, 0x2ff0, 0x30fe, 0x3211, 0x332b, 0x344c, 0x3572,
+ 0x369f, 0x37d2, 0x390d, 0x3a4e, 0x3b96, 0x3ce6, 0x3e3d, 0x3f9b,
+ 0x4101, 0x426f, 0x43e6, 0x4564, 0x46eb, 0x487a, 0x4a12, 0x4bb3,
+ 0x4d5d, 0x4f11, 0x50ce, 0x5295, 0x5466, 0x5642, 0x5827, 0x5a18,
+ 0x5c13, 0x5e19, 0x602b, 0x6249, 0x6472, 0x66a8, 0x68ea, 0x6b39,
+ 0x6d94, 0x6ffd, 0x7274, 0x74f8, 0x778b, 0x7a2c, 0x7cdc, 0x7f9b,
+ 0x826a, 0x8548, 0x8836, 0x8b35, 0x8e45, 0x9166, 0x9499, 0x97de,
+ 0x9b35, 0x9e9f, 0xa21c, 0xa5ad, 0xa952, 0xad0b, 0xb0da, 0xb4bd,
+ 0xb8b7, 0xbcc7, 0xc0ee, 0xc52d, 0xc983, 0xcdf1, 0xd279, 0xd71a,
+ 0xdbd5, 0xe0ab, 0xe59c, 0xeaa9, 0xefd3, 0xf519, 0xfa7d, 0xffff,
};
#endif /* DOC_HIDDEN */
int i;
short s[2];
} val_t;
-static inline int MULTI_DIV(int a, unsigned short b)
+static inline int MULTI_DIV_int(int a, unsigned short b)
{
val_t v, x, y;
v.i = a;
return y.i;
}
+/* (16bit x 16bit) >> 16 */
+#define MULTI_DIV_short(src,scale) (((int)(src) * (scale)) >> VOL_SCALE_SHIFT)
+
+
/*
* apply volumue attenuation
*
* TODO: use SIMD operations
*/
-static void snd_pcm_softvol_convert(snd_pcm_softvol_t *svol,
- const snd_pcm_channel_area_t *dst_areas,
- snd_pcm_uframes_t dst_offset,
- const snd_pcm_channel_area_t *src_areas,
- snd_pcm_uframes_t src_offset,
- unsigned int channels,
- snd_pcm_uframes_t frames,
- unsigned int cur_vol)
+
+#define CONVERT_AREA(TYPE) do { \
+ unsigned int ch, fr; \
+ TYPE *src, *dst; \
+ 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(TYPE); \
+ dst_step = snd_pcm_channel_area_step(dst_area) / sizeof(TYPE); \
+ 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 += src_step; \
+ dst += dst_step; \
+ } \
+ } else { \
+ while (fr--) { \
+ *dst = MULTI_DIV_##TYPE(*src, vol_scale);\
+ src += src_step; \
+ dst += dst_step; \
+ } \
+ } \
+ } \
+} while (0)
+
+
+
+#define GET_VOL_SCALE \
+ switch (ch) { \
+ case 0: \
+ case 2: \
+ vol_scale = (channels == ch + 1) ? vol_c : vol[0]; \
+ break; \
+ case 4: \
+ case 5: \
+ vol_scale = vol_c; \
+ break; \
+ default: \
+ vol_scale = vol[ch & 1]; \
+ break; \
+ }
+
+/* 2-channel stereo control */
+static void softvol_convert_stereo_vol(snd_pcm_softvol_t *svol,
+ const snd_pcm_channel_area_t *dst_areas,
+ snd_pcm_uframes_t dst_offset,
+ const snd_pcm_channel_area_t *src_areas,
+ snd_pcm_uframes_t src_offset,
+ unsigned int channels,
+ snd_pcm_uframes_t frames)
+{
+ const snd_pcm_channel_area_t *dst_area, *src_area;
+ unsigned int src_step, dst_step;
+ unsigned int vol_scale, vol[2], vol_c;
+
+ if (svol->cur_vol[0] == 0 && svol->cur_vol[1] == 0) {
+ snd_pcm_areas_silence(dst_areas, dst_offset, channels, frames,
+ svol->sformat);
+ return;
+ } else if (svol->cur_vol[0] == svol->max_val &&
+ svol->cur_vol[1] == svol->max_val) {
+ snd_pcm_areas_copy(dst_areas, dst_offset, src_areas, src_offset,
+ channels, frames, svol->sformat);
+ return;
+ }
+
+ vol[0] = svol->dB_value[svol->cur_vol[0]];
+ vol[1] = svol->dB_value[svol->cur_vol[1]];
+ vol_c = svol->dB_value[(svol->cur_vol[0] + svol->cur_vol[1]) / 2];
+ if (svol->sformat == SND_PCM_FORMAT_S16) {
+ /* 16bit samples */
+ CONVERT_AREA(short);
+ } else {
+ /* 32bit samples */
+ CONVERT_AREA(int);
+ }
+}
+
+#undef GET_VOL_SCALE
+#define GET_VOL_SCALE
+
+/* mono control */
+static void softvol_convert_mono_vol(snd_pcm_softvol_t *svol,
+ const snd_pcm_channel_area_t *dst_areas,
+ snd_pcm_uframes_t dst_offset,
+ const snd_pcm_channel_area_t *src_areas,
+ snd_pcm_uframes_t src_offset,
+ unsigned int channels,
+ snd_pcm_uframes_t frames)
{
const snd_pcm_channel_area_t *dst_area, *src_area;
unsigned int src_step, dst_step;
- unsigned int ch;
- unsigned int fr;
unsigned int vol_scale;
- if (cur_vol == 0) {
+ if (svol->cur_vol[0] == 0) {
snd_pcm_areas_silence(dst_areas, dst_offset, channels, frames,
svol->sformat);
return;
- } else if (cur_vol == svol->max_val) {
+ } else if (svol->cur_vol[0] == svol->max_val) {
snd_pcm_areas_copy(dst_areas, dst_offset, src_areas, src_offset,
channels, frames, svol->sformat);
return;
}
- vol_scale = svol->dB_value[cur_vol];
+ vol_scale = svol->dB_value[svol->cur_vol[0]];
if (svol->sformat == SND_PCM_FORMAT_S16) {
/* 16bit samples */
- short *src, *dst;
- 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(short);
- dst_step = snd_pcm_channel_area_step(dst_area) / sizeof(short);
- fr = frames;
- while (fr--) {
- *dst = ((int)*src * vol_scale) >> VOL_SCALE_SHIFT;
- src += src_step;
- dst += dst_step;
- }
- }
+ CONVERT_AREA(short);
} else {
/* 32bit samples */
- int *src, *dst;
- 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);
- fr = frames;
- while (fr--) {
- *dst = MULTI_DIV(*src, vol_scale);
- src += src_step;
- dst += dst_step;
- }
- }
+ CONVERT_AREA(int);
}
}
*
* TODO: mmap support?
*/
-static unsigned int get_current_volume(snd_pcm_softvol_t *svol)
+static void get_current_volume(snd_pcm_softvol_t *svol)
{
unsigned int val;
+ unsigned int i;
+
if (snd_ctl_elem_read(svol->ctl, &svol->elem) < 0)
- return 0;
- /* set max vol as default */
- val = svol->elem.value.integer.value[0];
- if (val > svol->max_val)
- val = svol->max_val;
- return val;
+ return;
+ for (i = 0; i < svol->cchannels; i++) {
+ val = svol->elem.value.integer.value[i];
+ if (val > svol->max_val)
+ val = svol->max_val;
+ svol->cur_vol[i] = val;
+ }
}
static void softvol_free(snd_pcm_softvol_t *svol)
_snd_pcm_hw_params_set_format(sparams, svol->sformat);
_snd_pcm_hw_params_set_subformat(sparams, SND_PCM_SUBFORMAT_STD);
}
- _snd_pcm_hw_params_set_subformat(sparams, SND_PCM_SUBFORMAT_STD);
return 0;
}
snd_pcm_softvol_t *svol = pcm->private_data;
if (size > *slave_sizep)
size = *slave_sizep;
- snd_pcm_softvol_convert(svol, slave_areas, slave_offset,
- areas, offset,
- pcm->channels,
- size, get_current_volume(svol));
+ get_current_volume(svol);
+ if (svol->cchannels == 1)
+ softvol_convert_mono_vol(svol, slave_areas, slave_offset,
+ areas, offset, pcm->channels, size);
+ else
+ softvol_convert_stereo_vol(svol, slave_areas, slave_offset,
+ areas, offset, pcm->channels, size);
*slave_sizep = size;
return size;
}
snd_pcm_softvol_t *svol = pcm->private_data;
if (size > *slave_sizep)
size = *slave_sizep;
- snd_pcm_softvol_convert(svol, areas, offset,
- slave_areas, slave_offset,
- pcm->channels,
- size, get_current_volume(svol));
+ get_current_volume(svol);
+ if (svol->cchannels == 1)
+ softvol_convert_mono_vol(svol, areas, offset, slave_areas,
+ slave_offset, pcm->channels, size);
+ else
+ softvol_convert_stereo_vol(svol, areas, offset, slave_areas,
+ slave_offset, pcm->channels, size);
*slave_sizep = size;
return size;
}
snd_pcm_dump(svol->plug.slave, out);
}
-static int add_user_ctl(snd_pcm_softvol_t *svol, snd_ctl_elem_info_t *cinfo)
+static int add_user_ctl(snd_pcm_softvol_t *svol, snd_ctl_elem_info_t *cinfo, int count)
{
int err;
+ unsigned int i;
- err = snd_ctl_elem_add_integer(svol->ctl, &cinfo->id, 1, 0, svol->max_val, 0);
+ err = snd_ctl_elem_add_integer(svol->ctl, &cinfo->id, count, 0, svol->max_val, 0);
if (err < 0)
return err;
- svol->elem.value.integer.value[0] = svol->max_val;
+ /* set max value as default */
+ for (i = 0; i < count; i++)
+ svol->elem.value.integer.value[i] = svol->max_val;
return snd_ctl_elem_write(svol->ctl, &svol->elem);
}
*/
static int softvol_load_control(snd_pcm_t *pcm, snd_pcm_softvol_t *svol,
int ctl_card, snd_ctl_elem_id_t *ctl_id,
- double min_dB, int resolution)
+ int cchannels, double min_dB, int resolution)
{
char tmp_name[32];
snd_pcm_info_t *info;
SNDERR("Cannot get info for CTL %s", tmp_name);
return err;
}
- err = add_user_ctl(svol, cinfo);
+ err = add_user_ctl(svol, cinfo, cchannels);
if (err < 0) {
SNDERR("Cannot add a control");
return err;
return 1; /* notify */
} else if (cinfo->type != SND_CTL_ELEM_TYPE_INTEGER ||
- cinfo->count != 1 ||
- cinfo->value.integer.min != 0 ||
- cinfo->value.integer.max != resolution - 1) {
- snd_ctl_elem_remove(svol->ctl, &cinfo->id);
- err = add_user_ctl(svol, cinfo);
- if (err < 0) {
- SNDERR("Cannot replace a control");
+ cinfo->count != (unsigned int)cchannels ||
+ cinfo->value.integer.min != 0 ||
+ cinfo->value.integer.max != resolution - 1) {
+ if ((err = snd_ctl_elem_remove(svol->ctl, &cinfo->id)) < 0) {
+ SNDERR("Control %s mismatch", tmp_name);
+ return err;
+ }
+ snd_ctl_elem_info_set_id(cinfo, ctl_id); /* reset numid */
+ if ((err = add_user_ctl(svol, cinfo, cchannels)) < 0) {
+ SNDERR("Cannot add a control");
return err;
}
}
svol->min_dB = min_dB;
for (i = 1; i < svol->max_val; i++) {
double db = svol->min_dB - ((i - 1) * svol->min_dB) / (svol->max_val - 1);
- double v = (pow(2.0, db / 10.0) * (double)(1 << VOL_SCALE_SHIFT));
+ double v = (pow(10.0, db / 20.0) * (double)(1 << VOL_SCALE_SHIFT));
svol->dB_value[i] = (unsigned short)v;
}
svol->dB_value[svol->max_val] = 65535;
int snd_pcm_softvol_open(snd_pcm_t **pcmp, const char *name,
snd_pcm_format_t sformat,
int ctl_card, snd_ctl_elem_id_t *ctl_id,
+ int cchannels,
double min_dB, int resolution,
snd_pcm_t *slave, int close_slave)
{
svol = calloc(1, sizeof(*svol));
if (! svol)
return -ENOMEM;
- err = softvol_load_control(slave, svol, ctl_card, ctl_id, min_dB, resolution);
+ err = softvol_load_control(slave, svol, ctl_card, ctl_id, cchannels,
+ min_dB, resolution);
if (err < 0) {
softvol_free(svol);
return err;
/* do softvol */
snd_pcm_plugin_init(&svol->plug);
svol->sformat = sformat;
+ svol->cchannels = cchannels;
svol->plug.read = snd_pcm_softvol_read_areas;
svol->plug.write = snd_pcm_softvol_write_areas;
svol->plug.undo_read = snd_pcm_plugin_undo_read_generic;
/*
* parse card index and id for the softvol control
*/
-static int parse_control_id(snd_config_t *conf, snd_ctl_elem_id_t *ctl_id, int *cardp)
+static int parse_control_id(snd_config_t *conf, snd_ctl_elem_id_t *ctl_id, int *cardp,
+ int *cchannelsp)
{
snd_config_iterator_t i, next;
int iface = SND_CTL_ELEM_IFACE_MIXER;
int err;
*cardp = -1;
+ *cchannelsp = 2;
snd_config_for_each(i, next, conf) {
snd_config_t *n = snd_config_iterator_entry(i);
const char *id;
}
continue;
}
+ if (strcmp(id, "count") == 0) {
+ long v;
+ if ((err = snd_config_get_integer(n, &v)) < 0) {
+ SNDERR("field %s is not an integer", id);
+ goto _err;
+ }
+ if (v < 1 || v > 2) {
+ SNDERR("Invalid count %ld", v);
+ goto _err;
+ }
+ *cchannelsp = v;
+ continue;
+ }
SNDERR("Unknown field %s", id);
return -EINVAL;
}
This plugin applies the software volume attenuation.
The format, rate and channels must match for both of source and destination.
+When the control is stereo (count=2), the channels are assumed to be either
+mono, 2.0, 2.1, 4.0, 4.1, 5.1 or 7.1.
+
If the control already exists and it's a system control (i.e. no
user-defined control), the plugin simply passes its slave without
any changes.
}
control {
name STR # control element id string
- [card STR] # control name (e.g. hw:0)
+ [card INT] # control card index
[iface STR] # interface of the element
[index INT] # index of the element
[device INT] # device number of the element
[subdevice INT] # subdevice number of the element
+ [count INT] # control channels 1 or 2 (default: 2)
}
- [min_dB REAL] # minimal dB value (default: -48 dB)
+ [min_dB REAL] # minimal dB value (default: -48.0)
[resolution INT] # resolution (default: 256)
}
\endcode
snd_ctl_elem_id_t *ctl_id;
int resolution = PRESET_RESOLUTION;
double min_dB = PRESET_MIN_DB;
- int card = -1;
+ int card = -1, cchannels = 2;
snd_config_for_each(i, next, conf) {
snd_config_t *n = snd_config_iterator_entry(i);
if (err < 0)
return err;
snd_ctl_elem_id_alloca(&ctl_id);
- if ((err = parse_control_id(control, ctl_id, &card)) < 0) {
+ if ((err = parse_control_id(control, ctl_id, &card, &cchannels)) < 0) {
snd_pcm_close(spcm);
return err;
}
- err = snd_pcm_softvol_open(pcmp, name, sformat, card, ctl_id, min_dB, resolution, spcm, 1);
+ err = snd_pcm_softvol_open(pcmp, name, sformat, card, ctl_id, cchannels,
+ min_dB, resolution, spcm, 1);
if (err < 0)
snd_pcm_close(spcm);
return err;
git://git.alsa-project.org / alsa-lib.git / commitdiff