alsa-lib/src/pcm/pcm_softvol.c
Takashi Iwai 5c71dd3ee7 Add dB range information to PCM softvol plugin
Added the dB range information to PCM softvol plugin.
Also, fixed the coefficient table to match with the
accurate dB step 0.20dB.
2006-08-25 11:46:19 +02:00

940 lines
27 KiB
C

/**
* \file pcm/pcm_softvol.c
* \ingroup PCM_Plugins
* \brief PCM Soft Volume Plugin Interface
* \author Takashi Iwai <tiwai@suse.de>
* \date 2004
*/
/*
* PCM - Soft Volume Plugin
* Copyright (c) 2004 by Takashi Iwai <tiwai@suse.de>
*
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <byteswap.h>
#include <math.h>
#include "pcm_local.h"
#include "pcm_plugin.h"
#ifndef PIC
/* entry for static linking */
const char *_snd_module_pcm_softvol = "";
#endif
#ifndef DOC_HIDDEN
typedef struct {
/* 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;
} snd_pcm_softvol_t;
#define VOL_SCALE_SHIFT 16
#define PRESET_RESOLUTION 256
#define PRESET_MIN_DB -51.0
static unsigned short preset_dB_value[PRESET_RESOLUTION] = {
0x00b8, 0x00bd, 0x00c1, 0x00c5, 0x00ca, 0x00cf, 0x00d4, 0x00d9,
0x00de, 0x00e3, 0x00e8, 0x00ed, 0x00f3, 0x00f9, 0x00fe, 0x0104,
0x010a, 0x0111, 0x0117, 0x011e, 0x0124, 0x012b, 0x0132, 0x0139,
0x0140, 0x0148, 0x0150, 0x0157, 0x015f, 0x0168, 0x0170, 0x0179,
0x0181, 0x018a, 0x0194, 0x019d, 0x01a7, 0x01b0, 0x01bb, 0x01c5,
0x01cf, 0x01da, 0x01e5, 0x01f1, 0x01fc, 0x0208, 0x0214, 0x0221,
0x022d, 0x023a, 0x0248, 0x0255, 0x0263, 0x0271, 0x0280, 0x028f,
0x029e, 0x02ae, 0x02be, 0x02ce, 0x02df, 0x02f0, 0x0301, 0x0313,
0x0326, 0x0339, 0x034c, 0x035f, 0x0374, 0x0388, 0x039d, 0x03b3,
0x03c9, 0x03df, 0x03f7, 0x040e, 0x0426, 0x043f, 0x0458, 0x0472,
0x048d, 0x04a8, 0x04c4, 0x04e0, 0x04fd, 0x051b, 0x053a, 0x0559,
0x0579, 0x0599, 0x05bb, 0x05dd, 0x0600, 0x0624, 0x0648, 0x066e,
0x0694, 0x06bb, 0x06e3, 0x070c, 0x0737, 0x0762, 0x078e, 0x07bb,
0x07e9, 0x0818, 0x0848, 0x087a, 0x08ac, 0x08e0, 0x0915, 0x094b,
0x0982, 0x09bb, 0x09f5, 0x0a30, 0x0a6d, 0x0aab, 0x0aeb, 0x0b2c,
0x0b6f, 0x0bb3, 0x0bf9, 0x0c40, 0x0c89, 0x0cd4, 0x0d21, 0x0d6f,
0x0dbf, 0x0e11, 0x0e65, 0x0ebb, 0x0f12, 0x0f6c, 0x0fc8, 0x1026,
0x1087, 0x10e9, 0x114e, 0x11b5, 0x121f, 0x128b, 0x12fa, 0x136b,
0x13df, 0x1455, 0x14ce, 0x154a, 0x15c9, 0x164b, 0x16d0, 0x1758,
0x17e4, 0x1872, 0x1904, 0x1999, 0x1a32, 0x1ace, 0x1b6e, 0x1c11,
0x1cb9, 0x1d64, 0x1e13, 0x1ec7, 0x1f7e, 0x203a, 0x20fa, 0x21bf,
0x2288, 0x2356, 0x2429, 0x2500, 0x25dd, 0x26bf, 0x27a6, 0x2892,
0x2984, 0x2a7c, 0x2b79, 0x2c7c, 0x2d85, 0x2e95, 0x2fab, 0x30c7,
0x31ea, 0x3313, 0x3444, 0x357c, 0x36bb, 0x3801, 0x394f, 0x3aa5,
0x3c02, 0x3d68, 0x3ed6, 0x404d, 0x41cd, 0x4355, 0x44e6, 0x4681,
0x4826, 0x49d4, 0x4b8c, 0x4d4f, 0x4f1c, 0x50f3, 0x52d6, 0x54c4,
0x56be, 0x58c3, 0x5ad4, 0x5cf2, 0x5f1c, 0x6153, 0x6398, 0x65e9,
0x6849, 0x6ab7, 0x6d33, 0x6fbf, 0x7259, 0x7503, 0x77bd, 0x7a87,
0x7d61, 0x804d, 0x834a, 0x8659, 0x897a, 0x8cae, 0x8ff5, 0x934f,
0x96bd, 0x9a40, 0x9dd8, 0xa185, 0xa548, 0xa922, 0xad13, 0xb11b,
0xb53b, 0xb973, 0xbdc5, 0xc231, 0xc6b7, 0xcb58, 0xd014, 0xd4ed,
0xd9e3, 0xdef6, 0xe428, 0xe978, 0xeee8, 0xf479, 0xfa2b, 0xffff,
};
/* (32bit x 16bit) >> 16 */
typedef union {
int i;
short s[2];
} val_t;
static inline int MULTI_DIV_int(int a, unsigned short b, int swap)
{
val_t v, x, y;
v.i = swap ? (int)bswap_32(a) : a;
y.i = 0;
#if __BYTE_ORDER == __LITTLE_ENDIAN
x.i = (unsigned int)v.s[0] * b;
y.s[0] = x.s[1];
y.i += (int)v.s[1] * b;
#else
x.i = (unsigned int)v.s[1] * b;
y.s[1] = x.s[0];
y.i += (int)v.s[0] * b;
#endif
return swap ? (int)bswap_32(y.i) : y.i;
}
/* (16bit x 16bit) >> 16 */
#define MULTI_DIV_short(src, scale, swap) \
(swap \
? bswap_16(((short) bswap_16(src) * (scale)) >> VOL_SCALE_SHIFT) \
: (((int) (src) * (scale)) >> VOL_SCALE_SHIFT))
#endif /* DOC_HIDDEN */
/*
* apply volumue attenuation
*
* TODO: use SIMD operations
*/
#ifndef DOC_HIDDEN
#define CONVERT_AREA(TYPE, swap) 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 = (TYPE) MULTI_DIV_##TYPE(*src, vol_scale, swap); \
src += src_step; \
dst += dst_step; \
} \
} \
} \
} while (0)
#define CONVERT_AREA_S24_3LE() do { \
unsigned int ch, fr; \
unsigned char *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); \
dst_step = snd_pcm_channel_area_step(dst_area); \
GET_VOL_SCALE; \
fr = frames; \
if (! vol_scale) { \
while (fr--) { \
dst[0] = dst[1] = dst[2] = 0; \
dst += dst_step; \
} \
} else if (vol_scale == 0xffff) { \
while (fr--) { \
dst[0] = src[0]; \
dst[1] = src[1]; \
dst[2] = src[2]; \
src += dst_step; \
dst += src_step; \
} \
} else { \
while (fr--) { \
tmp = src[0] | \
(src[1] << 8) | \
(((signed char *) src)[2] << 16); \
tmp = MULTI_DIV_int(tmp, vol_scale, 0); \
dst[0] = tmp; \
dst[1] = tmp >> 8; \
dst[2] = tmp >> 16; \
src += dst_step; \
dst += src_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; \
}
#endif /* DOC_HIDDEN */
/* 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];
switch (svol->sformat) {
case SND_PCM_FORMAT_S16_LE:
case SND_PCM_FORMAT_S16_BE:
/* 16bit samples */
CONVERT_AREA(short,
!snd_pcm_format_cpu_endian(svol->sformat));
break;
case SND_PCM_FORMAT_S32_LE:
case SND_PCM_FORMAT_S32_BE:
/* 32bit samples */
CONVERT_AREA(int,
!snd_pcm_format_cpu_endian(svol->sformat));
break;
case SND_PCM_FORMAT_S24_3LE:
CONVERT_AREA_S24_3LE();
break;
default:
break;
}
}
#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 vol_scale;
if (svol->cur_vol[0] == 0) {
snd_pcm_areas_silence(dst_areas, dst_offset, channels, frames,
svol->sformat);
return;
} 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[svol->cur_vol[0]];
switch (svol->sformat) {
case SND_PCM_FORMAT_S16_LE:
case SND_PCM_FORMAT_S16_BE:
/* 16bit samples */
CONVERT_AREA(short,
!snd_pcm_format_cpu_endian(svol->sformat));
break;
case SND_PCM_FORMAT_S32_LE:
case SND_PCM_FORMAT_S32_BE:
/* 32bit samples */
CONVERT_AREA(int,
!snd_pcm_format_cpu_endian(svol->sformat));
break;
case SND_PCM_FORMAT_S24_3LE:
CONVERT_AREA_S24_3LE();
break;
default:
break;
}
}
/*
* get the current volume value from driver
*
* TODO: mmap support?
*/
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;
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)
{
if (svol->plug.gen.close_slave)
snd_pcm_close(svol->plug.gen.slave);
if (svol->ctl)
snd_ctl_close(svol->ctl);
if (svol->dB_value && svol->dB_value != preset_dB_value)
free(svol->dB_value);
free(svol);
}
static int snd_pcm_softvol_close(snd_pcm_t *pcm)
{
snd_pcm_softvol_t *svol = pcm->private_data;
softvol_free(svol);
return 0;
}
static int snd_pcm_softvol_hw_refine_cprepare(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params)
{
int err;
snd_pcm_softvol_t *svol = pcm->private_data;
snd_pcm_access_mask_t access_mask = { SND_PCM_ACCBIT_SHM };
snd_pcm_format_mask_t format_mask = {
{
(1ULL << SND_PCM_FORMAT_S16_LE) |
(1ULL << SND_PCM_FORMAT_S16_BE) |
(1ULL << SND_PCM_FORMAT_S32_LE) |
(1ULL << SND_PCM_FORMAT_S32_BE),
(1ULL << (SND_PCM_FORMAT_S24_3LE - 32))
}
};
if (svol->sformat != SND_PCM_FORMAT_UNKNOWN) {
snd_pcm_format_mask_none(&format_mask);
snd_pcm_format_mask_set(&format_mask, svol->sformat);
}
err = _snd_pcm_hw_param_set_mask(params, SND_PCM_HW_PARAM_ACCESS,
&access_mask);
if (err < 0)
return err;
err = _snd_pcm_hw_param_set_mask(params, SND_PCM_HW_PARAM_FORMAT,
&format_mask);
if (err < 0)
return err;
err = _snd_pcm_hw_params_set_subformat(params, SND_PCM_SUBFORMAT_STD);
if (err < 0)
return err;
err = _snd_pcm_hw_param_set_min(params, SND_PCM_HW_PARAM_CHANNELS, 1, 0);
if (err < 0)
return err;
params->info &= ~(SND_PCM_INFO_MMAP | SND_PCM_INFO_MMAP_VALID);
return 0;
}
static int snd_pcm_softvol_hw_refine_sprepare(snd_pcm_t *pcm, snd_pcm_hw_params_t *sparams)
{
snd_pcm_softvol_t *svol = pcm->private_data;
snd_pcm_access_mask_t saccess_mask = { SND_PCM_ACCBIT_MMAP };
_snd_pcm_hw_params_any(sparams);
_snd_pcm_hw_param_set_mask(sparams, SND_PCM_HW_PARAM_ACCESS,
&saccess_mask);
if (svol->sformat != SND_PCM_FORMAT_UNKNOWN) {
_snd_pcm_hw_params_set_format(sparams, svol->sformat);
_snd_pcm_hw_params_set_subformat(sparams, SND_PCM_SUBFORMAT_STD);
}
return 0;
}
static int snd_pcm_softvol_hw_refine_schange(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params,
snd_pcm_hw_params_t *sparams)
{
snd_pcm_softvol_t *svol = pcm->private_data;
int err;
unsigned int links = (SND_PCM_HW_PARBIT_CHANNELS |
SND_PCM_HW_PARBIT_RATE |
SND_PCM_HW_PARBIT_PERIODS |
SND_PCM_HW_PARBIT_PERIOD_SIZE |
SND_PCM_HW_PARBIT_PERIOD_TIME |
SND_PCM_HW_PARBIT_BUFFER_SIZE |
SND_PCM_HW_PARBIT_BUFFER_TIME |
SND_PCM_HW_PARBIT_TICK_TIME);
if (svol->sformat == SND_PCM_FORMAT_UNKNOWN)
links |= (SND_PCM_HW_PARBIT_FORMAT |
SND_PCM_HW_PARBIT_SUBFORMAT |
SND_PCM_HW_PARBIT_SAMPLE_BITS);
err = _snd_pcm_hw_params_refine(sparams, links, params);
if (err < 0)
return err;
return 0;
}
static int snd_pcm_softvol_hw_refine_cchange(snd_pcm_t *pcm,
snd_pcm_hw_params_t *params,
snd_pcm_hw_params_t *sparams)
{
snd_pcm_softvol_t *svol = pcm->private_data;
int err;
unsigned int links = (SND_PCM_HW_PARBIT_CHANNELS |
SND_PCM_HW_PARBIT_RATE |
SND_PCM_HW_PARBIT_PERIODS |
SND_PCM_HW_PARBIT_PERIOD_SIZE |
SND_PCM_HW_PARBIT_PERIOD_TIME |
SND_PCM_HW_PARBIT_BUFFER_SIZE |
SND_PCM_HW_PARBIT_BUFFER_TIME |
SND_PCM_HW_PARBIT_TICK_TIME);
if (svol->sformat == SND_PCM_FORMAT_UNKNOWN)
links |= (SND_PCM_HW_PARBIT_FORMAT |
SND_PCM_HW_PARBIT_SUBFORMAT |
SND_PCM_HW_PARBIT_SAMPLE_BITS);
err = _snd_pcm_hw_params_refine(params, links, sparams);
if (err < 0)
return err;
return 0;
}
static int snd_pcm_softvol_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
{
return snd_pcm_hw_refine_slave(pcm, params,
snd_pcm_softvol_hw_refine_cprepare,
snd_pcm_softvol_hw_refine_cchange,
snd_pcm_softvol_hw_refine_sprepare,
snd_pcm_softvol_hw_refine_schange,
snd_pcm_generic_hw_refine);
}
static int snd_pcm_softvol_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params)
{
snd_pcm_softvol_t *svol = pcm->private_data;
snd_pcm_t *slave = svol->plug.gen.slave;
int err = snd_pcm_hw_params_slave(pcm, params,
snd_pcm_softvol_hw_refine_cchange,
snd_pcm_softvol_hw_refine_sprepare,
snd_pcm_softvol_hw_refine_schange,
snd_pcm_generic_hw_params);
if (err < 0)
return err;
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_S32_LE &&
slave->format != SND_PCM_FORMAT_S32_BE) {
SNDERR("softvol supports only S16_LE, S16_BE, S24_3LE, S32_LE "
" or S32_BE");
return -EINVAL;
}
svol->sformat = slave->format;
return 0;
}
static snd_pcm_uframes_t
snd_pcm_softvol_write_areas(snd_pcm_t *pcm,
const snd_pcm_channel_area_t *areas,
snd_pcm_uframes_t offset,
snd_pcm_uframes_t size,
const snd_pcm_channel_area_t *slave_areas,
snd_pcm_uframes_t slave_offset,
snd_pcm_uframes_t *slave_sizep)
{
snd_pcm_softvol_t *svol = pcm->private_data;
if (size > *slave_sizep)
size = *slave_sizep;
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;
}
static snd_pcm_uframes_t
snd_pcm_softvol_read_areas(snd_pcm_t *pcm,
const snd_pcm_channel_area_t *areas,
snd_pcm_uframes_t offset,
snd_pcm_uframes_t size,
const snd_pcm_channel_area_t *slave_areas,
snd_pcm_uframes_t slave_offset,
snd_pcm_uframes_t *slave_sizep)
{
snd_pcm_softvol_t *svol = pcm->private_data;
if (size > *slave_sizep)
size = *slave_sizep;
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;
}
static void snd_pcm_softvol_dump(snd_pcm_t *pcm, snd_output_t *out)
{
snd_pcm_softvol_t *svol = pcm->private_data;
snd_output_printf(out, "Soft volume PCM\n");
snd_output_printf(out, "Control: %s\n", svol->elem.id.name);
snd_output_printf(out, "min_dB: %g\n", svol->min_dB);
snd_output_printf(out, "resolution: %d\n", svol->max_val + 1);
if (pcm->setup) {
snd_output_printf(out, "Its setup is:\n");
snd_pcm_dump_setup(pcm, out);
}
snd_output_printf(out, "Slave: ");
snd_pcm_dump(svol->plug.gen.slave, out);
}
static int add_tlv_info(snd_pcm_softvol_t *svol, snd_ctl_elem_info_t *cinfo)
{
unsigned int tlv[4];
tlv[0] = SND_CTL_TLVT_DB_SCALE;
tlv[1] = 2 * sizeof(int);
tlv[2] = svol->min_dB * 100;
tlv[3] = -svol->min_dB * 100 / svol->max_val;
return snd_ctl_elem_tlv_write(svol->ctl, &cinfo->id, tlv);
}
static int add_user_ctl(snd_pcm_softvol_t *svol, snd_ctl_elem_info_t *cinfo, int count)
{
int err;
int i;
err = snd_ctl_elem_add_integer(svol->ctl, &cinfo->id, count, 0, svol->max_val, 0);
if (err < 0)
return err;
add_tlv_info(svol, cinfo);
/* 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);
}
/*
* load and set up user-control
* returns 0 if the user-control is found or created,
* returns 1 if the control is a hw control,
* or a negative error code
*/
static int softvol_load_control(snd_pcm_t *pcm, snd_pcm_softvol_t *svol,
int ctl_card, snd_ctl_elem_id_t *ctl_id,
int cchannels, double min_dB, int resolution)
{
char tmp_name[32];
snd_pcm_info_t *info;
snd_ctl_elem_info_t *cinfo;
int err;
unsigned int i;
if (ctl_card < 0) {
snd_pcm_info_alloca(&info);
err = snd_pcm_info(pcm, info);
if (err < 0)
return err;
ctl_card = snd_pcm_info_get_card(info);
if (ctl_card < 0) {
SNDERR("No card defined for softvol control");
return -EINVAL;
}
}
sprintf(tmp_name, "hw:%d", ctl_card);
err = snd_ctl_open(&svol->ctl, tmp_name, 0);
if (err < 0) {
SNDERR("Cannot open CTL %s", tmp_name);
return err;
}
svol->elem.id = *ctl_id;
svol->max_val = resolution - 1;
svol->min_dB = min_dB;
snd_ctl_elem_info_alloca(&cinfo);
snd_ctl_elem_info_set_id(cinfo, ctl_id);
if ((err = snd_ctl_elem_info(svol->ctl, cinfo)) < 0) {
if (err != -ENOENT) {
SNDERR("Cannot get info for CTL %s", tmp_name);
return err;
}
err = add_user_ctl(svol, cinfo, cchannels);
if (err < 0) {
SNDERR("Cannot add a control");
return err;
}
} else {
if (! (cinfo->access & SNDRV_CTL_ELEM_ACCESS_USER)) {
/* hardware control exists */
return 1; /* notify */
} else if (cinfo->type != SND_CTL_ELEM_TYPE_INTEGER ||
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;
}
} else {
/* check TLV availability */
unsigned int tlv[4];
err = snd_ctl_elem_tlv_read(svol->ctl, &cinfo->id, tlv, sizeof(tlv));
if (err < 0)
add_tlv_info(svol, cinfo);
}
}
if (min_dB == PRESET_MIN_DB && resolution == PRESET_RESOLUTION)
svol->dB_value = preset_dB_value;
else {
#ifndef HAVE_SOFT_FLOAT
svol->dB_value = calloc(resolution, sizeof(unsigned short));
if (! svol->dB_value) {
SNDERR("cannot allocate dB table");
return -ENOMEM;
}
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(10.0, db / 20.0) * (double)(1 << VOL_SCALE_SHIFT));
svol->dB_value[i] = (unsigned short)v;
}
svol->dB_value[svol->max_val] = 65535;
#else
SNDERR("Cannot handle the given min_dB and resolution");
return -EINVAL;
#endif
}
return 0;
}
static snd_pcm_ops_t snd_pcm_softvol_ops = {
.close = snd_pcm_softvol_close,
.info = snd_pcm_generic_info,
.hw_refine = snd_pcm_softvol_hw_refine,
.hw_params = snd_pcm_softvol_hw_params,
.hw_free = snd_pcm_generic_hw_free,
.sw_params = snd_pcm_generic_sw_params,
.channel_info = snd_pcm_generic_channel_info,
.dump = snd_pcm_softvol_dump,
.nonblock = snd_pcm_generic_nonblock,
.async = snd_pcm_generic_async,
.mmap = snd_pcm_generic_mmap,
.munmap = snd_pcm_generic_munmap,
};
/**
* \brief Creates a new SoftVolume PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param sformat Slave format
* \param ctl_card card index of the control
* \param ctl_id The control element
* \param cchannels PCM channels
* \param min_dB minimal dB value
* \param resolution resolution of control
* \param slave Slave PCM handle
* \param close_slave When set, the slave PCM handle is closed with copy PCM
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
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)
{
snd_pcm_t *pcm;
snd_pcm_softvol_t *svol;
int err;
assert(pcmp && slave);
if (sformat != SND_PCM_FORMAT_UNKNOWN &&
sformat != SND_PCM_FORMAT_S16_LE &&
sformat != SND_PCM_FORMAT_S16_BE &&
sformat != SND_PCM_FORMAT_S24_3LE &&
sformat != SND_PCM_FORMAT_S32_LE &&
sformat != SND_PCM_FORMAT_S32_BE)
return -EINVAL;
svol = calloc(1, sizeof(*svol));
if (! svol)
return -ENOMEM;
err = softvol_load_control(slave, svol, ctl_card, ctl_id, cchannels,
min_dB, resolution);
if (err < 0) {
softvol_free(svol);
return err;
}
if (err > 0) { /* hardware control - no need for softvol! */
softvol_free(svol);
*pcmp = slave; /* just pass the slave */
return 0;
}
/* 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;
svol->plug.undo_write = snd_pcm_plugin_undo_write_generic;
svol->plug.gen.slave = slave;
svol->plug.gen.close_slave = close_slave;
err = snd_pcm_new(&pcm, SND_PCM_TYPE_SOFTVOL, name, slave->stream, slave->mode);
if (err < 0) {
softvol_free(svol);
return err;
}
pcm->ops = &snd_pcm_softvol_ops;
pcm->fast_ops = &snd_pcm_plugin_fast_ops;
pcm->private_data = svol;
pcm->poll_fd = slave->poll_fd;
pcm->poll_events = slave->poll_events;
/*
* Since the softvol converts on the place, and the format/channels
* must be identical between source and destination, we don't need
* an extra buffer.
*/
pcm->mmap_shadow = 1;
snd_pcm_set_hw_ptr(pcm, &svol->plug.hw_ptr, -1, 0);
snd_pcm_set_appl_ptr(pcm, &svol->plug.appl_ptr, -1, 0);
*pcmp = pcm;
return 0;
}
/* in pcm_misc.c */
int snd_pcm_parse_control_id(snd_config_t *conf, snd_ctl_elem_id_t *ctl_id, int *cardp,
int *cchannelsp, int *hwctlp);
/*! \page pcm_plugins
\section pcm_plugins_softvol Plugin: Soft Volume
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.
\code
pcm.name {
type softvol # Soft Volume conversion PCM
slave STR # Slave name
# or
slave { # Slave definition
pcm STR # Slave PCM name
# or
pcm { } # Slave PCM definition
[format STR] # Slave format
}
control {
name STR # control element id string
[card STR] # 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: -51.0)
[resolution INT] # resolution (default: 256)
}
\endcode
\subsection pcm_plugins_softvol_funcref Function reference
<UL>
<LI>snd_pcm_softvol_open()
<LI>_snd_pcm_softvol_open()
</UL>
*/
/**
* \brief Creates a new Soft Volume PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param root Root configuration node
* \param conf Configuration node with Soft Volume PCM description
* \param stream Stream type
* \param mode Stream mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int _snd_pcm_softvol_open(snd_pcm_t **pcmp, const char *name,
snd_config_t *root, snd_config_t *conf,
snd_pcm_stream_t stream, int mode)
{
snd_config_iterator_t i, next;
int err;
snd_pcm_t *spcm;
snd_config_t *slave = NULL, *sconf;
snd_config_t *control = NULL;
snd_pcm_format_t sformat = SND_PCM_FORMAT_UNKNOWN;
snd_ctl_elem_id_t *ctl_id;
int resolution = PRESET_RESOLUTION;
double min_dB = PRESET_MIN_DB;
int card = -1, cchannels = 2;
snd_config_for_each(i, next, conf) {
snd_config_t *n = snd_config_iterator_entry(i);
const char *id;
if (snd_config_get_id(n, &id) < 0)
continue;
if (snd_pcm_conf_generic_id(id))
continue;
if (strcmp(id, "slave") == 0) {
slave = n;
continue;
}
if (strcmp(id, "control") == 0) {
control = n;
continue;
}
if (strcmp(id, "resolution") == 0) {
long v;
err = snd_config_get_integer(n, &v);
if (err < 0) {
SNDERR("Invalid resolution value");
return err;
}
resolution = v;
continue;
}
if (strcmp(id, "min_dB") == 0) {
err = snd_config_get_real(n, &min_dB);
if (err < 0) {
SNDERR("Invalid min_dB value");
return err;
}
continue;
}
SNDERR("Unknown field %s", id);
return -EINVAL;
}
if (!slave) {
SNDERR("slave is not defined");
return -EINVAL;
}
if (!control) {
SNDERR("control is not defined");
return -EINVAL;
}
if (min_dB >= 0) {
SNDERR("min_dB must be a negative value");
return -EINVAL;
}
if (resolution < 0 || resolution > 1024) {
SNDERR("Invalid resolution value %d", resolution);
return -EINVAL;
}
err = snd_pcm_slave_conf(root, slave, &sconf, 1,
SND_PCM_HW_PARAM_FORMAT, 0, &sformat);
if (err < 0)
return err;
if (sformat != SND_PCM_FORMAT_UNKNOWN &&
sformat != SND_PCM_FORMAT_S16_LE &&
sformat != SND_PCM_FORMAT_S16_BE &&
sformat != SND_PCM_FORMAT_S24_3LE &&
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");
snd_config_delete(sconf);
return -EINVAL;
}
err = snd_pcm_open_slave(&spcm, root, sconf, stream, mode, conf);
snd_config_delete(sconf);
if (err < 0)
return err;
snd_ctl_elem_id_alloca(&ctl_id);
if ((err = snd_pcm_parse_control_id(control, ctl_id, &card, &cchannels, NULL)) < 0) {
snd_pcm_close(spcm);
return err;
}
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;
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_softvol_open, SND_PCM_DLSYM_VERSION);
#endif