ALSA: hdspm - Allow the TCO and SYNC-IN to be used in slave mode

When using the additional Time Code Option module in slave mode or the
SYNC-In wordclock connector, the sample rate needs to be returned by
hdspm_external_sample_rate().

Since this sample rate may contain any value with 1Hz granularity, we
need to round it to a common rate as done by the OSX driver.

[Fixed missing function declarations by tiwai]

Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Adrian Knoth 2013-03-10 00:37:22 +01:00 committed by Takashi Iwai
parent 3f7bf918bf
commit fcdc4ba1d8

View File

@ -1076,6 +1076,20 @@ static int snd_hdspm_use_is_exclusive(struct hdspm *hdspm)
return ret;
}
/* round arbitary sample rates to commonly known rates */
static int hdspm_round_frequency(int rate)
{
if (rate < 38050)
return 32000;
if (rate < 46008)
return 44100;
else
return 48000;
}
static int hdspm_tco_sync_check(struct hdspm *hdspm);
static int hdspm_sync_in_sync_check(struct hdspm *hdspm);
/* check for external sample rate */
static int hdspm_external_sample_rate(struct hdspm *hdspm)
{
@ -1217,21 +1231,44 @@ static int hdspm_external_sample_rate(struct hdspm *hdspm)
break;
}
/* QS and DS rates normally can not be detected
* automatically by the card. Only exception is MADI
* in 96k frame mode.
*
* So if we read SS values (32 .. 48k), check for
* user-provided DS/QS bits in the control register
* and multiply the base frequency accordingly.
*/
if (rate <= 48000) {
if (hdspm->control_register & HDSPM_QuadSpeed)
rate *= 4;
else if (hdspm->control_register &
HDSPM_DoubleSpeed)
rate *= 2;
} /* endif HDSPM_madiLock */
/* check sample rate from TCO or SYNC_IN */
{
bool is_valid_input = 0;
bool has_sync = 0;
syncref = hdspm_autosync_ref(hdspm);
if (HDSPM_AUTOSYNC_FROM_TCO == syncref) {
is_valid_input = 1;
has_sync = (HDSPM_SYNC_CHECK_SYNC ==
hdspm_tco_sync_check(hdspm));
} else if (HDSPM_AUTOSYNC_FROM_SYNC_IN == syncref) {
is_valid_input = 1;
has_sync = (HDSPM_SYNC_CHECK_SYNC ==
hdspm_sync_in_sync_check(hdspm));
}
if (is_valid_input && has_sync) {
rate = hdspm_round_frequency(
hdspm_get_pll_freq(hdspm));
}
}
/* QS and DS rates normally can not be detected
* automatically by the card. Only exception is MADI
* in 96k frame mode.
*
* So if we read SS values (32 .. 48k), check for
* user-provided DS/QS bits in the control register
* and multiply the base frequency accordingly.
*/
if (rate <= 48000) {
if (hdspm->control_register & HDSPM_QuadSpeed)
rate *= 4;
else if (hdspm->control_register &
HDSPM_DoubleSpeed)
rate *= 2;
}
break;
}