Sound Mega-commit. Expect further cleanup until code freeze.

For a slightly thorough explaination, please refer to
	[1] http://people.freebsd.org/~ariff/SOUND_4.TXT.html .

Summary of changes includes:

1 Volume Per-Channel (vpc).  Provides private / standalone volume control
  unique per-stream pcm channel without touching master volume / pcm.
  Applications can directly use SNDCTL_DSP_[GET|SET][PLAY|REC]VOL, or for
  backwards compatibility, SOUND_MIXER_PCM through the opened dsp device
  instead of /dev/mixer.  Special "bypass" mode is enabled through
  /dev/mixer which will automatically detect if the adjustment is made
  through /dev/mixer and forward its request to this private volume
  controller.  Changes to this volume object will not interfere with
  other channels.

  Requirements:
    - SNDCTL_DSP_[GET|SET][PLAY|REC]_VOL are newer ioctls (OSSv4) which
      require specific application modifications (preferred).
    - No modifications required for using bypass mode, so applications
      like mplayer or xmms should work out of the box.

  Kernel hints:
    - hint.pcm.%d.vpc (0 = disable vpc).

  Kernel sysctls:
    - hw.snd.vpc_mixer_bypass (default: 1).  Enable or disable /dev/mixer
      bypass mode.
    - hw.snd.vpc_autoreset (default: 1).  By default, closing/opening
      /dev/dsp will reset the volume back to 0 db gain/attenuation.
      Setting this to 0 will preserve its settings across device
      closing/opening.
    - hw.snd.vpc_reset (default: 0).  Panic/reset button to reset all
      volume settings back to 0 db.
    - hw.snd.vpc_0db (default: 45).  0 db relative to linear mixer value.

2 High quality fixed-point Bandlimited SINC sampling rate converter,
  based on Julius O'Smith's Digital Audio Resampling -
  http://ccrma.stanford.edu/~jos/resample/.  It includes a filter design
  script written in awk (the clumsiest joke I've ever written)
    - 100% 32bit fixed-point, 64bit accumulator.
    - Possibly among the fastest (if not fastest) of its kind.
    - Resampling quality is tunable, either runtime or during kernel
      compilation (FEEDER_RATE_PRESETS).
    - Quality can be further customized during kernel compilation by
      defining FEEDER_RATE_PRESETS in /etc/make.conf.

  Kernel sysctls:
    - hw.snd.feeder_rate_quality.
      0 - Zero-order Hold (ZOH).  Fastest, bad quality.
      1 - Linear Interpolation (LINEAR).  Slightly slower than ZOH,
          better quality but still does not eliminate aliasing.
      2 - (and above) - Sinc Interpolation(SINC).  Best quality.  SINC
          quality always start from 2 and above.

  Rough quality comparisons:
    - http://people.freebsd.org/~ariff/z_comparison/

3 Bit-perfect mode.  Bypasses all feeder/dsp effects.  Pure sound will be
  directly fed into the hardware.

4 Parametric (compile time) Software Equalizer (Bass/Treble mixer). Can
  be customized by defining FEEDER_EQ_PRESETS in /etc/make.conf.

5 Transparent/Adaptive Virtual Channel. Now you don't have to disable
  vchans in order to make digital format pass through.  It also makes
  vchans more dynamic by choosing a better format/rate among all the
  concurrent streams, which means that dev.pcm.X.play.vchanformat/rate
  becomes sort of optional.

6 Exclusive Stream, with special open() mode O_EXCL.  This will "mute"
  other concurrent vchan streams and only allow a single channel with
  O_EXCL set to keep producing sound.

Other Changes:
    * most feeder_* stuffs are compilable in userland. Let's not
      speculate whether we should go all out for it (save that for
      FreeBSD 16.0-RELEASE).
    * kobj signature fixups, thanks to Andriy Gapon <avg@freebsd.org>
    * pull out channel mixing logic out of vchan.c and create its own
      feeder_mixer for world justice.
    * various refactoring here and there, for good or bad.
    * activation of few more OSSv4 ioctls() (see [1] above).
    * opt_snd.h for possible compile time configuration:
      (mostly for debugging purposes, don't try these at home)
        SND_DEBUG
        SND_DIAGNOSTIC
        SND_FEEDER_MULTIFORMAT
        SND_FEEDER_FULL_MULTIFORMAT
        SND_FEEDER_RATE_HP
        SND_PCM_64
        SND_OLDSTEREO

Manual page updates are on the way.

Tested by:	joel, Olivier SMEDTS <olivier at gid0 d org>, too many
          	unsung / unnamed heroes.

5 files changed, 49 insertions, 19 deletions

diff --git a/sys/dev/sound/macio/aoa.c b/sys/dev/sound/macio/aoa.c
index 54efe4f..5c012d3 100644
--- a/sys/dev/sound/macio/aoa.c
+++ b/sys/dev/sound/macio/aoa.c
@@ -43,8 +43,14 @@
 #include <machine/bus.h>
 #include <sys/rman.h>
 #include <dev/ofw/ofw_bus.h>
+
+#ifdef HAVE_KERNEL_OPTION_HEADERS
+#include "opt_snd.h"
+#endif
+
 #include <dev/sound/pcm/sound.h>
 #include <dev/sound/macio/aoa.h>
+
 #include "mixer_if.h"
 
 struct aoa_dma {
@@ -138,7 +144,7 @@ aoa_dma_delete(struct aoa_dma *dma)
 	free(dma, M_DEVBUF);
 }
 
-static int
+static u_int32_t
 aoa_chan_setblocksize(kobj_t obj, void *data, u_int32_t blocksz)
 {
 	struct aoa_dma 		*dma = data;
@@ -186,13 +192,13 @@ aoa_chan_setformat(kobj_t obj, void *data, u_int32_t format)
 {
 	DPRINTF(("aoa_chan_setformat: format = %u\n", format));
 
-	if (format != (AFMT_STEREO | AFMT_S16_BE))
+	if (format != SND_FORMAT(AFMT_S16_BE, 2, 0))
 		return (EINVAL);
 
 	return (0);
 }
 
-static int
+static u_int32_t
 aoa_chan_setspeed(kobj_t obj, void *data, u_int32_t speed)
 {
 	DPRINTF(("aoa_chan_setspeed: speed = %u\n", speed));
@@ -200,7 +206,7 @@ aoa_chan_setspeed(kobj_t obj, void *data, u_int32_t speed)
 	return (44100);
 }
 
-static int
+static u_int32_t
 aoa_chan_getptr(kobj_t obj, void *data)
 {
 	struct aoa_dma 	 *dma = data;
@@ -332,7 +338,7 @@ aoa_interrupt(void *xsc)
 }
 
 static u_int32_t sc_fmt[] = {
-	AFMT_S16_BE | AFMT_STEREO,
+	SND_FORMAT(AFMT_S16_BE, 2, 0),
 	0
 };
 static struct pcmchan_caps aoa_caps = {44100, 44100, sc_fmt, 0};
@@ -352,7 +358,7 @@ static kobj_method_t aoa_chan_methods[] = {
 	KOBJMETHOD(channel_trigger,	aoa_chan_trigger),
 	KOBJMETHOD(channel_getptr,	aoa_chan_getptr),
 	KOBJMETHOD(channel_getcaps,	aoa_chan_getcaps),
-	{ 0, 0 }
+	KOBJMETHOD_END
 };
 CHANNEL_DECLARE(aoa_chan);
 
diff --git a/sys/dev/sound/macio/davbus.c b/sys/dev/sound/macio/davbus.c
index 15909f8..46c731b 100644
--- a/sys/dev/sound/macio/davbus.c
+++ b/sys/dev/sound/macio/davbus.c
@@ -40,7 +40,13 @@
 #include <sys/rman.h>
 
 #include <dev/ofw/ofw_bus.h>
+
+#ifdef HAVE_KERNEL_OPTION_HEADERS
+#include "opt_snd.h"
+#endif
+
 #include <dev/sound/pcm/sound.h>
+
 #include <dev/sound/macio/aoa.h>
 #include <dev/sound/macio/davbusreg.h>
 
@@ -115,7 +121,7 @@ static void	burgundy_set_outputs(struct davbus_softc *d, u_int mask);
 static u_int	burgundy_read_status(struct davbus_softc *d, u_int status);
 static int	burgundy_set(struct snd_mixer *m, unsigned dev, unsigned left,
 		    unsigned right);
-static int	burgundy_setrecsrc(struct snd_mixer *m, u_int32_t src);
+static u_int32_t	burgundy_setrecsrc(struct snd_mixer *m, u_int32_t src);
 
 static kobj_method_t burgundy_mixer_methods[] = {
 	KOBJMETHOD(mixer_init, 		burgundy_init),
@@ -123,7 +129,7 @@ static kobj_method_t burgundy_mixer_methods[] = {
 	KOBJMETHOD(mixer_reinit, 	burgundy_reinit),
 	KOBJMETHOD(mixer_set, 		burgundy_set),
 	KOBJMETHOD(mixer_setrecsrc,	burgundy_setrecsrc),
-	{ 0, 0 }
+	KOBJMETHOD_END
 };
 
 MIXER_DECLARE(burgundy_mixer);
@@ -293,7 +299,7 @@ burgundy_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
 	return (0);
 }
 
-static int
+static u_int32_t
 burgundy_setrecsrc(struct snd_mixer *m, u_int32_t src)
 {
 	return (0);
@@ -311,7 +317,7 @@ static void	screamer_set_outputs(struct davbus_softc *d, u_int mask);
 static u_int	screamer_read_status(struct davbus_softc *d, u_int status);
 static int	screamer_set(struct snd_mixer *m, unsigned dev, unsigned left,
 		    unsigned right);
-static int	screamer_setrecsrc(struct snd_mixer *m, u_int32_t src);
+static u_int32_t	screamer_setrecsrc(struct snd_mixer *m, u_int32_t src);
 
 static kobj_method_t screamer_mixer_methods[] = {
 	KOBJMETHOD(mixer_init, 		screamer_init),
@@ -319,7 +325,7 @@ static kobj_method_t screamer_mixer_methods[] = {
 	KOBJMETHOD(mixer_reinit, 	screamer_reinit),
 	KOBJMETHOD(mixer_set, 		screamer_set),
 	KOBJMETHOD(mixer_setrecsrc,	screamer_setrecsrc),
-	{ 0, 0 }
+	KOBJMETHOD_END
 };
 
 MIXER_DECLARE(screamer_mixer);
@@ -479,7 +485,7 @@ screamer_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
 	return (0);
 }
 
-static int
+static u_int32_t
 screamer_setrecsrc(struct snd_mixer *m, u_int32_t src)
 {
 	return (0);
diff --git a/sys/dev/sound/macio/i2s.c b/sys/dev/sound/macio/i2s.c
index 11a0826..d1a5463 100644
--- a/sys/dev/sound/macio/i2s.c
+++ b/sys/dev/sound/macio/i2s.c
@@ -72,8 +72,14 @@
 #include <machine/pio.h>
 #include <sys/rman.h>
 #include <dev/ofw/ofw_bus.h>
+
+#ifdef HAVE_KERNEL_OPTION_HEADERS
+#include "opt_snd.h"
+#endif
+
 #include <dev/sound/pcm/sound.h>
 #include <dev/sound/macio/aoa.h>
+
 #include <powerpc/powermac/macgpiovar.h>
 
 struct i2s_softc {
@@ -530,7 +536,7 @@ i2s_setup(struct i2s_softc *sc, u_int rate, u_int wordsize, u_int sclk_fs)
 		 *	to set sane defaults (44100).
 		 */
 		printf("i2s_setup: changing format not supported yet.\n");
-		return (EOPNOTSUPP);
+		return (ENOTSUP);
 
 #ifdef notyet
 		if (obio_fcr_isset(OBIO_FCR1, I2S0CLKEN)) {
diff --git a/sys/dev/sound/macio/snapper.c b/sys/dev/sound/macio/snapper.c
index 8acca10..6e9b6fe 100644
--- a/sys/dev/sound/macio/snapper.c
+++ b/sys/dev/sound/macio/snapper.c
@@ -75,7 +75,13 @@
 #include <dev/iicbus/iicbus.h>
 #include <dev/iicbus/iiconf.h>
 #include <dev/ofw/ofw_bus.h>
+
+#ifdef HAVE_KERNEL_OPTION_HEADERS
+#include "opt_snd.h"
+#endif
+
 #include <dev/sound/pcm/sound.h>
+
 #include "mixer_if.h"
 
 extern kobj_class_t i2s_mixer_class;
@@ -94,7 +100,7 @@ static void	snapper_uninit(struct snd_mixer *m);
 static int	snapper_reinit(struct snd_mixer *m);
 static int	snapper_set(struct snd_mixer *m, unsigned dev, unsigned left,
 		    unsigned right);
-static int	snapper_setrecsrc(struct snd_mixer *m, u_int32_t src);
+static u_int32_t	snapper_setrecsrc(struct snd_mixer *m, u_int32_t src);
 
 static device_method_t snapper_methods[] = {
 	/* Device interface. */
@@ -121,7 +127,7 @@ static kobj_method_t snapper_mixer_methods[] = {
 	KOBJMETHOD(mixer_reinit, 	snapper_reinit),
 	KOBJMETHOD(mixer_set, 		snapper_set),
 	KOBJMETHOD(mixer_setrecsrc, 	snapper_setrecsrc),
-	{ 0, 0 }
+	KOBJMETHOD_END
 };
 
 MIXER_DECLARE(snapper_mixer);
@@ -478,7 +484,7 @@ snapper_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
 	return (0);
 }
 
-static int
+static u_int32_t
 snapper_setrecsrc(struct snd_mixer *m, u_int32_t src)
 {
 	return (0);
diff --git a/sys/dev/sound/macio/tumbler.c b/sys/dev/sound/macio/tumbler.c
index 3007ece..57b77bc 100644
--- a/sys/dev/sound/macio/tumbler.c
+++ b/sys/dev/sound/macio/tumbler.c
@@ -75,7 +75,13 @@
 #include <dev/iicbus/iicbus.h>
 #include <dev/iicbus/iiconf.h>
 #include <dev/ofw/ofw_bus.h>
+
+#ifdef HAVE_KERNEL_OPTION_HEADERS
+#include "opt_snd.h"
+#endif
+
 #include <dev/sound/pcm/sound.h>
+
 #include "mixer_if.h"
 
 extern kobj_class_t i2s_mixer_class;
@@ -94,7 +100,7 @@ static void	tumbler_uninit(struct snd_mixer *m);
 static int	tumbler_reinit(struct snd_mixer *m);
 static int	tumbler_set(struct snd_mixer *m, unsigned dev, unsigned left,
 		    unsigned right);
-static int	tumbler_setrecsrc(struct snd_mixer *m, u_int32_t src);
+static u_int32_t	tumbler_setrecsrc(struct snd_mixer *m, u_int32_t src);
 
 static device_method_t tumbler_methods[] = {
 	/* Device interface. */
@@ -121,7 +127,7 @@ static kobj_method_t tumbler_mixer_methods[] = {
 	KOBJMETHOD(mixer_reinit, 	tumbler_reinit),
 	KOBJMETHOD(mixer_set, 		tumbler_set),
 	KOBJMETHOD(mixer_setrecsrc, 	tumbler_setrecsrc),
-	{ 0, 0 }
+	KOBJMETHOD_END
 };
 
 MIXER_DECLARE(tumbler_mixer);
@@ -424,7 +430,7 @@ tumbler_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
 	return (0);
 }
 
-static int
+static u_int32_t
 tumbler_setrecsrc(struct snd_mixer *m, u_int32_t src)
 {
 	return (0);