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Add handling of linear volume in simple mixer

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Added the handling of linear volume TLV in the simple mixer layer.
This commit is contained in:
Takashi Iwai 2006-08-28 13:27:41 +02:00
parent 4962ec5a5c
commit b0bbcd0697
2 changed files with 69 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

5
include/control.h
View file

@ -170,6 +170,11 @@ typedef enum _snd_ctl_event_type {
#define SND_CTL_TLVT_CONTAINER 0x0000
/** TLV type - basic dB scale */
#define SND_CTL_TLVT_DB_SCALE 0x0001
/** TLV type - linear volume */
#define SND_CTL_TLVT_DB_LINEAR 0x0002
/** Mute state */
#define SND_CTL_TLV_DB_GAIN_MUTE -9999999
/** CTL type */
typedef enum _snd_ctl_type {

68
src/mixer/simple_none.c
View file

@ -1008,6 +1008,13 @@ static int parse_db_range(struct selem_str *rec, unsigned int *tlv,
}
break;
case SND_CTL_TLVT_DB_SCALE:
#ifndef HAVE_SOFT_FLOAT
case SND_CTL_TLVT_DB_LINEAR:
#endif
if (size < 2 * sizeof(int)) {
SNDERR("Invalid dB_scale TLV size");
return -EINVAL;
}
rec->db_info = malloc(size + sizeof(int) * 2);
if (! rec->db_info)
return -ENOMEM;
@ -1025,22 +1032,47 @@ static int parse_db_range(struct selem_str *rec, unsigned int *tlv,
static int convert_to_dB(snd_hctl_elem_t *ctl, struct selem_str *rec,
long volume, long *db_gain)
{
int min, step, mute;
if (init_db_range(ctl, rec) < 0)
return -EINVAL;
switch (rec->db_info[0]) {
case SND_CTL_TLVT_DB_SCALE:
case SND_CTL_TLVT_DB_SCALE: {
int min, step, mute;
min = rec->db_info[2];
step = (rec->db_info[3] & 0xffff);
mute = (rec->db_info[3] >> 16) & 1;
if (mute && volume == rec->min)
*db_gain = -9999999;
*db_gain = SND_CTL_TLV_DB_GAIN_MUTE;
else
*db_gain = (volume - rec->min) * step + min;
return 0;
}
#ifndef HAVE_SOFT_FLOAT
case SND_CTL_TLVT_DB_LINEAR: {
int mindb = rec->db_info[2];
int maxdb = rec->db_info[3];
if (volume <= rec->min || rec->max <= rec->min)
*db_gain = mindb;
else if (volume >= rec->max)
*db_gain = maxdb;
else {
double val = (double)(volume - rec->min) /
(double)(rec->max - rec->min);
if (mindb <= SND_CTL_TLV_DB_GAIN_MUTE)
*db_gain = (long)(100.0 * 20.0 * log10(val)) +
maxdb;
else {
/* FIXME: precalculate and cache these values */
double lmin = pow(10.0, mindb/20.0);
double lmax = pow(10.0, maxdb/20.0);
val = (lmax - lmin) * val + lmin;
*db_gain = (long)(100.0 * 20.0 * log10(val));
}
}
return 0;
}
#endif
}
return -EINVAL;
}
@ -1115,6 +1147,10 @@ static int get_dB_range(snd_hctl_elem_t *ctl, struct selem_str *rec,
step = (rec->db_info[3] & 0xffff);
*max = *min + (long)(step * (rec->max - rec->min));
return 0;
case SND_CTL_TLVT_DB_LINEAR:
*min = (int)rec->db_info[2];
*max = (int)rec->db_info[3];
return 0;
}
return -EINVAL;
}
@ -1160,6 +1196,30 @@ static int convert_from_dB(snd_hctl_elem_t *ctl, struct selem_str *rec,
}
return 0;
}
#ifndef HAVE_SOFT_FLOAT
case SND_CTL_TLVT_DB_LINEAR: {
int min, max;
min = rec->db_info[2];
max = rec->db_info[3];
if (db_gain <= min)
*value = rec->min;
else if (db_gain >= max)
*value = rec->max;
else {
/* FIXME: precalculate and cache vmin and vmax */
double vmin, vmax, v;
vmin = (min <= SND_CTL_TLV_DB_GAIN_MUTE) ? 0.0 :
pow(10.0, (double)min / 20.0);
vmax = !max ? 1.0 : pow(10.0, (double)max / 20.0);
v = pow(10.0, (double)db_gain / 20.0);
v = (v - vmin) * (rec->max - rec->min) / (vmax - vmin);
if (xdir > 0)
v = ceil(v);
*value = (long)v + rec->min;
}
return 0;
}
#endif
default:
break;
}