ALSA: hdspm - Work around broken DDS value on PCI RME MADI

On PCI RME MADI cards, the PLL register does not contain the proper
value, so the calculated system_sample_rate is wrong. In this case, we
simply return the cached rate from struct hdspm.

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 2012-05-30 14:23:18 +02:00 committed by Takashi Iwai
parent 5cd5d7c449
commit a97bda7d29
1 changed files with 7 additions and 0 deletions

View File

@ -1988,6 +1988,13 @@ static int hdspm_get_system_sample_rate(struct hdspm *hdspm)
period = hdspm_read(hdspm, HDSPM_RD_PLL_FREQ);
rate = hdspm_calc_dds_value(hdspm, period);
if (rate > 207000) {
/* Unreasonable high sample rate as seen on PCI MADI cards.
* Use the cached value instead.
*/
rate = hdspm->system_sample_rate;
}
return rate;
}