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authorAdrian Knoth <adi@drcomp.erfurt.thur.de>2011-08-15 00:22:54 +0200
committerTakashi Iwai <tiwai@suse.de>2011-08-15 10:25:39 +0200
commit2e61027079ed70f54fec41ddb8fa8af37d79d8d8 (patch)
tree5995e5800a182bb739fe2d5e2d9f556c6f7e73ef
parent7cb155ff3e4645188c42d707300e36cfce44e28a (diff)
downloadlinux-2e61027079ed70f54fec41ddb8fa8af37d79d8d8.tar.bz2
ALSA: hdspm - Enable 32 samples/period on RME RayDAT/AIO
Newer RME cards like RayDAT and AIO support 32 samples per period. This value is encoded as {1,1,1} in the HDSP_LatencyMask bits in the control register. Since {1,1,1} is also the representation for 8192 samples/period on older RME cards, we have to special case 32 samples and 32768 bytes according to the actual card. Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
-rw-r--r--sound/pci/rme9652/hdspm.c25
1 files changed, 20 insertions, 5 deletions
diff --git a/sound/pci/rme9652/hdspm.c b/sound/pci/rme9652/hdspm.c
index 1a52a1ae1f4c..92ac64ced29a 100644
--- a/sound/pci/rme9652/hdspm.c
+++ b/sound/pci/rme9652/hdspm.c
@@ -1323,12 +1323,27 @@ static int hdspm_set_interrupt_interval(struct hdspm *s, unsigned int frames)
spin_lock_irq(&s->lock);
- frames >>= 7;
- n = 0;
- while (frames) {
- n++;
- frames >>= 1;
+ if (32 == frames) {
+ /* Special case for new RME cards like RayDAT/AIO which
+ * support period sizes of 32 samples. Since latency is
+ * encoded in the three bits of HDSP_LatencyMask, we can only
+ * have values from 0 .. 7. While 0 still means 64 samples and
+ * 6 represents 4096 samples on all cards, 7 represents 8192
+ * on older cards and 32 samples on new cards.
+ *
+ * In other words, period size in samples is calculated by
+ * 2^(n+6) with n ranging from 0 .. 7.
+ */
+ n = 7;
+ } else {
+ frames >>= 7;
+ n = 0;
+ while (frames) {
+ n++;
+ frames >>= 1;
+ }
}
+
s->control_register &= ~HDSPM_LatencyMask;
s->control_register |= hdspm_encode_latency(n);