[PATCH 3.16.y-ckt 115/183] ALSA: hdspm - Constrain periods to 2 on older cards

[Luis Henriques]

3.16.7-ckt8 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Adrian Knoth <adi at 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 at drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 sound/pci/rme9652/hdspm.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/sound/pci/rme9652/hdspm.c b/sound/pci/rme9652/hdspm.c
index cb82b593473a..f292bed4424d 100644
--- a/sound/pci/rme9652/hdspm.c
+++ b/sound/pci/rme9652/hdspm.c
@@ -6114,6 +6114,9 @@ static int snd_hdspm_playback_open(struct snd_pcm_substream *substream)
 		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);
 		break;
 	}
 
@@ -6188,6 +6191,9 @@ static int snd_hdspm_capture_open(struct snd_pcm_substream *substream)
 		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);
 		break;
 	}