Welcome to Once-a-year Sound Mega-Commit. Enjoy numerous updates and fixes

in every sense.

General
-------

- Multichannel safe, endian safe, format safe
   * Large part of critical pcm filters such as vchan.c, feeder_rate.c,
     feeder_volume.c, feeder_fmt.c and feeder.c has been rewritten so that
     using them does not cause the pcm data to be converted to 16bit little
     endian.
   * Macrosses for accessing pcm data safely are defined within sound.h in
     the form of PCM_READ_* / PCM_WRITE_*
   * Currently, most of them are probably limited for mono/stereo handling,
     but the future addition of true multichannel will be much easier.

- Low latency operation
  * Well, this require lot more works to do not just within sound driver,
    but we're heading towards right direction. Buffer/block sizing within
    channel.c is rewritten to calculate precise allocation for various
    combination of sample/data/rate size. As a result, applying correct
    SNDCTL_DSP_POLICY value will achive expected latency behaviour simmilar
    to what commercial 4front driver do.
  * Signal handling fix. ctrl+c of "cat /dev/zero > /dev/dsp" does not
    result long delay.
  * Eliminate sound truncation if the sound data is too small.
    DIY:
      1) Download / extract
         http://people.freebsd.org/~ariff/lowlatency/shortfiles.tar.gz
      2) Do a comparison between "cat state*.au > /dev/dsp" and
         "for x in state*.au ; do cat $x > /dev/dsp ; done"
         - there should be no "perceivable" differences.
    Double close for PR kern/31445.

  CAVEAT: Low latency come with (unbearable) price especially for poorly
          written applications. Applications that trying to act smarter
	  by requesting (wrong) blocksize/blockcount will suffer the most.
	  Fixup samples/patches can be found at:
	  http://people.freebsd.org/~ariff/ports/

- Switch minimum/maximum sampling rate limit to "1" and "2016000" (48k * 42)
  due to closer compatibility with 4front driver.
  Discussed with: marcus@ (long time ago?)

- All driver specific sysctls in the form of "hw.snd.pcm%d.*" have been
  moved to their own dev sysctl nodes, notably:
  hw.snd.pcm%d.vchans -> dev.pcm.%d.vchans
  Bump __FreeBSD_version.

Driver specific
---------------

- Ditto for sysctls.

- snd_atiixp, snd_es137x, snd_via8233, snd_hda
  * Numerous cleanups and fixes.
  * _EXPERIMENTAL_ polling mode support using simple callout_* mechanisme.
   This was intended for pure debugging and latency measurement, but proven
   good enough in few unexpected and rare cases (such as problematic shared
   IRQ with GIANT devices - USB). Polling can be enabled/disabled through
   dev.pcm.0.polling. Disabled by default.

- snd_ich
  * Fix possible overflow during speed calibration. Delay final
    initialization (pcm_setstatus) after calibration finished.
    PR: kern/100169
    Tested by: Kevin Overman <oberman@es.net>
  * Inverted EAPD for few Nec VersaPro.
    PR: kern/104715
    Submitted by: KAWATA Masahiko <kawata@mta.biglobe.ne.jp>

Thanks to various people, notably Joel Dahl, Yuriy Tsibizov, Kevin Oberman,
those at #freebsd-azalia @ freenode and others for testing.

Joel Dahl will do the manpage update.

1 files changed, 16 insertions, 17 deletions

diff --git a/sys/dev/sound/pcm/dsp.c b/sys/dev/sound/pcm/dsp.c
index 56f50a7cdfc4..940c3fde57df 100644
--- a/sys/dev/sound/pcm/dsp.c
+++ b/sys/dev/sound/pcm/dsp.c
@@ -215,10 +215,12 @@ dsp_open(struct cdev *i_dev, int flags, int mode, struct thread *td)
 		fmt = 0;
 		break;
 
-	case SND_DEV_DSPREC:
+	case SND_DEV_DSPHW:
+		/*
+		 * HW *specific* access without channel numbering confusion
+		 * caused by "first come first served" by dsp_clone().
+		 */
 		fmt = AFMT_U8;
-		if (flags & FWRITE)
-			return EINVAL;
 		chnum = PCMCHAN(i_dev);
 		break;
 
@@ -768,7 +770,7 @@ dsp_ioctl(struct cdev *i_dev, u_long cmd, caddr_t arg, int mode, struct thread *
 		/* chn_sync may sleep */
 		if (wrch) {
 			CHN_LOCK(wrch);
-			chn_sync(wrch, sndbuf_getsize(wrch->bufsoft) - 4);
+			chn_sync(wrch, 0);
 			CHN_UNLOCK(wrch);
 		}
 		break;
@@ -1085,12 +1087,11 @@ dsp_ioctl(struct cdev *i_dev, u_long cmd, caddr_t arg, int mode, struct thread *
 
 	case SNDCTL_DSP_GETODELAY:
 		if (wrch) {
-			struct snd_dbuf *b = wrch->bufhard;
 	        	struct snd_dbuf *bs = wrch->bufsoft;
 
 			CHN_LOCK(wrch);
 			/* XXX abusive DMA update: chn_wrupdate(wrch); */
-			*arg_i = sndbuf_getready(b) + sndbuf_getready(bs);
+			*arg_i = sndbuf_getready(bs);
 			CHN_UNLOCK(wrch);
 		} else
 			ret = EINVAL;
@@ -2131,31 +2132,29 @@ dsp_oss_syncstart(int sg_id)
 static int
 dsp_oss_policy(struct pcm_channel *wrch, struct pcm_channel *rdch, int policy)
 {
-	int fragln, fragsz, maxfrags, ret;
+	int ret;
+
+	if (policy < CHN_POLICY_MIN || policy > CHN_POLICY_MAX)
+		return EIO;
 
 	/* Default: success */
 	ret = 0;
 
-	/* Scale policy [0..10] to fragment size [2^4..2^16]. */
-	fragln = policy;
-	RANGE(fragln, 0, 10);
-	fragln += 4;
-	fragsz = 1 << fragln;
-
-	maxfrags = CHN_2NDBUFMAXSIZE / fragsz;
-
 	if (rdch) {
 		CHN_LOCK(rdch);
-		ret = chn_setblocksize(rdch, maxfrags, fragsz);
+		ret = chn_setlatency(rdch, policy);
 		CHN_UNLOCK(rdch);
 	}
 
 	if (wrch && ret == 0) {
 		CHN_LOCK(wrch);
-		ret = chn_setblocksize(wrch, maxfrags, fragsz);
+		ret = chn_setlatency(wrch, policy);
 		CHN_UNLOCK(wrch);
 	}
 
+	if (ret)
+		ret = EIO;
+
 	return ret;
 }