[PATCH 3.2 042/221] ALSA: hdspm - Constrain periods to 2 on older cards

Ben Hutchings
2015-05-05T02:05:28Z

From: Adrian Knoth <adi@drcomp.erfurt.thur.de>

commit f0153c3d948c1764f6c920a0675d86fc1d75813e upstream.

RME RayDAT and AIO use a fixed buffer size of 16384 samples. With period
sizes of 32-4096, this translates to 4-512 periods.

The older RME cards have a variable buffer size but require exactly two
periods.

This patch enforces nperiods=2 on those cards.

Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
sound/pci/rme9652/hdspm.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/sound/pci/rme9652/hdspm.c
+++ b/sound/pci/rme9652/hdspm.c
@@ -6040,6 +6040,12 @@ static int snd_hdspm_capture_open(struct
snd_pcm_hw_constraint_minmax(runtime,
SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
64, 8192);
+ snd_pcm_hw_constraint_minmax(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS,
+ 2, 2);
+ snd_pcm_hw_constraint_minmax(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS,
+ 2, 2);
break;
}