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ALSA: hdspm - Refactor SS/DS/QS clock multiplier into function

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When the DoubleSpeed or QuadSpeed bit is set, the SingleSpeed frequency
has to be multiplied accordingly. Since this functionality will be
required at least twice, refactor it into a separate function.

The second reference to the newly introduced hdspm_rate_multiplier()
will be in a separate commit.

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 2013-05-31 12:57:10 +02:00 committed by Takashi Iwai
parent a8cd714804
commit a8a729fa06
1 changed files with 22 additions and 15 deletions
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37
sound/pci/rme9652/hdspm.c
View file

@ -1091,6 +1091,26 @@ static int hdspm_round_frequency(int rate)
return 48000;
}
/* 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.
*/
static int hdspm_rate_multiplier(struct hdspm *hdspm, int rate)
{
if (rate <= 48000) {
if (hdspm->control_register & HDSPM_QuadSpeed)
return rate * 4;
else if (hdspm->control_register &
HDSPM_DoubleSpeed)
return rate * 2;
};
return rate;
}
static int hdspm_tco_sync_check(struct hdspm *hdspm);
static int hdspm_sync_in_sync_check(struct hdspm *hdspm);
@ -1268,21 +1288,8 @@ static int hdspm_external_sample_rate(struct hdspm *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;
}
rate = hdspm_rate_multiplier(hdspm, rate);
break;
}