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Add preamble value configuration for iec958 plugin

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The preamble values can be defined in iec958 plugin configuration.
As default, Z/Y/X=8/4/2 is used.  CMI8338 has different values,
so override in its configuration.
This commit is contained in:
Takashi Iwai 2004-12-15 15:17:36 +00:00
parent 0256e1e8c9
commit 73aa2549d9
2 changed files with 63 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

3
src/conf/cards/CMI8338-SWIEC.conf
View file

@ -95,6 +95,9 @@ CMI8338-SWIEC.pcm.iec958.0 {
device 2
}
status [ $AES0 $AES1 $AES2 $AES3 ]
preamble.z 3
preamble.y 5
preamble.x 9
}
capture.pcm {
type hw

66
src/pcm/pcm_iec958.c
View file

@ -59,8 +59,11 @@ struct snd_pcm_iec958 {
unsigned int counter;
unsigned char status[24];
unsigned int byteswap;
unsigned char preamble[3]; /* B/M/W or Z/X/Y */
};
enum { PREAMBLE_Z, PREAMBLE_X, PREAMBLE_Y };
#endif /* DOC_HIDDEN */
/*
@ -114,11 +117,11 @@ static inline u_int32_t iec958_subframe(snd_pcm_iec958_t *iec, u_int32_t data, i
/* Preamble */
if (! iec->counter)
data |= 0x03; /* Block start, 'Z' */
data |= iec->preamble[PREAMBLE_Z]; /* Block start, 'Z' */
else if (! channel)
data |= 0x05; /* odd sub frame, 'Y' */
data |= iec->preamble[PREAMBLE_Y]; /* odd sub frame, 'Y' */
else
data |= 0x09; /* even sub frame, 'X' */
data |= iec->preamble[PREAMBLE_X]; /* even sub frame, 'X' */
if (iec->byteswap)
data = bswap_32(data);
@ -437,7 +440,10 @@ static snd_pcm_ops_t snd_pcm_iec958_ops = {
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave, const unsigned char *status_bits)
int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat,
snd_pcm_t *slave, int close_slave,
const unsigned char *status_bits,
const unsigned char *preamble_vals)
{
snd_pcm_t *pcm;
snd_pcm_iec958_t *iec;
@ -473,6 +479,8 @@ int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfo
else
memcpy(iec->status, default_status_bits, sizeof(default_status_bits));
memcpy(iec->preamble, preamble_vals, 3);
err = snd_pcm_new(&pcm, SND_PCM_TYPE_IEC958, name, slave->stream, slave->mode);
if (err < 0) {
free(iec);
@ -508,6 +516,12 @@ pcm.name {
pcm { } # Slave PCM definition
}
[status status-bytes] # IEC958 status bits (given in byte array)
# IEC958 preamble bits definitions
# B/M/W or Z/X/Y, B = block start, M = even subframe, W = odd subframe
# As default, Z = 0x08, Y = 0x04, X = 0x02
[preamble.z or preamble.b val]
[preamble.x or preamble.m val]
[preamble.y or preamble.w val]
}
\endcode
@ -541,9 +555,12 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
int err;
snd_pcm_t *spcm;
snd_config_t *slave = NULL, *sconf;
snd_config_t *status = NULL;
snd_config_t *status = NULL, *preamble = NULL;
snd_pcm_format_t sformat;
unsigned char status_bits[24];
unsigned char preamble_vals[3] = {
0x08, 0x02, 0x04 /* Z, X, Y */
};
snd_config_for_each(i, next, conf) {
snd_config_t *n = snd_config_iterator_entry(i);
@ -564,6 +581,14 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
status = n;
continue;
}
if (strcmp(id, "preamble") == 0) {
if (snd_config_get_type(n) != SND_CONFIG_TYPE_COMPOUND) {
SNDERR("Invalid type for %s", id);
return -EINVAL;
}
preamble = n;
continue;
}
SNDERR("Unknown field %s", id);
return -EINVAL;
}
@ -590,6 +615,33 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
}
// fprintf(stderr, "STATUS bits: %02x %02x %02x %02x\n", status_bits[0], status_bits[1], status_bits[2], status_bits[3]);
}
if (preamble) {
snd_config_iterator_t i, inext;
snd_config_for_each(i, inext, status) {
long val;
snd_config_t *n = snd_config_iterator_entry(i);
const char *id;
int idx;
if (snd_config_get_id(n, &id) < 0)
continue;
if (strcmp(id, "b") == 0 || strcmp(id, "z") == 0)
idx = PREAMBLE_Z;
else if (strcmp(id, "m") == 0 || strcmp(id, "x") == 0)
idx = PREAMBLE_X;
else if (strcmp(id, "w") == 0 || strcmp(id, "y") == 0)
idx = PREAMBLE_Y;
else {
SNDERR("invalid IEC958 preamble type %s", id);
return -EINVAL;
}
err = snd_config_get_integer(n, &val);
if (err < 0) {
SNDERR("invalid IEC958 preamble value");
return err;
}
preamble_vals[idx] = val;
}
}
if (!slave) {
SNDERR("slave is not defined");
return -EINVAL;
@ -609,7 +661,9 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
snd_config_delete(sconf);
if (err < 0)
return err;
err = snd_pcm_iec958_open(pcmp, name, sformat, spcm, 1, status ? status_bits : NULL);
err = snd_pcm_iec958_open(pcmp, name, sformat, spcm, 1,
status ? status_bits : NULL,
preamble_vals);
if (err < 0)
snd_pcm_close(spcm);
return err;