diff options
| author | Adrian Knoth <adi@drcomp.erfurt.thur.de> | 2011-08-15 00:22:54 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2011-08-15 10:25:39 +0200 |
| commit | 2e61027079ed70f54fec41ddb8fa8af37d79d8d8 (patch) | |
| tree | 5995e5800a182bb739fe2d5e2d9f556c6f7e73ef | |
| parent | 7cb155ff3e4645188c42d707300e36cfce44e28a (diff) | |
| download | linux-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.c | 25 |
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); |