freebsd-dev/sys/dev/sound/pcm/fake.c
Alexander Leidinger 87506547d2 Whats New:
1. Support wide range sampling rate, as low as 1hz up to int32 max
   (which is, insane) through new feeder_rate, multiple precisions
   choice (32/64 bit converter). This is indeed, quite insane, but it
   does give us more room and flexibility. Plenty sysctl options to
   adjust resampling characteristics.
2. Support 24/32 bit pcm format conversion through new, much improved,
   simplified and optimized feeder_fmt.

Changes:
1. buffer.c / dsp.c / sound.h
   * Support for 24/32 AFMT.
2. feeder_rate.c
   * New implementation of sampling rate conversion with 32/64 bit
     precision, 1 - int32max hz (which is, ridiculous, yet very
     addictive).  Much improved / smarter buffer management to not
     cause any missing samples at the end of conversion process
   * Tunable sysctls for various aspect:
       hw.snd.feeder_rate_ratemin - minimum allowable sampling rate
       (default to 4000)
       hw.snd.feeder_rate_ratemax - maximum allowable sampling rate
       (default to 1102500)
       hw.snd.feeder_rate_buffersize - conversion buffer size
       (default to 8192)
       hw.snd.feeder_rate_scaling - scaling / conversion method
       (please refer to the source for explaination). Default to
       previous implementation type.
3. feeder_fmt.c / sound.h
   * New implementation, support for 24/32bit conversion, optimized,
     and simplified. Few routines has been removed (8 to xlaw, 16 to
     8). It just doesn't make sense.
4. channel.c
   * Support for 24/32 AFMT
   * Fix wrong xruns increment, causing incorrect underruns statistic
     while using vchans.
5. vchan.c
   * Support for 24/32 AFMT
   * Proper speed / rate detection especially for fixed rate ac97.
     User can override it using kernel hint:
     hint.pcm.<unit>.vchanrate="xxxx".

Notes / Issues:
        * Virtual Channels (vchans)
          Enabling vchans can really, really help to solve overrun
          issues.  This is quite understandable, because it operates
          entirely within its own buffering system without relying on
          hardware interrupt / state. Even if you don't need vchan,
          just enable single channel can help much. Few soundcards
          (notably via8233x, sblive, possibly others) have their own
          hardware multi channel, and this is unfortunately beyond
          vchan reachability.
        * The arrival of 24/32 also come with a price. Applications
          that can do 24/32bit playback need to be recompiled (notably
          mplayer).  Use (recompiled) mplayer to experiment / test /
          debug this various format using -af format=fmt. Note that
          24bit seeking in mplayer is a little bit broken, sometimes
          can cause silence or loud static noise. Pausing / seeking
          few times can solve this problem.
          You don't have to rebuild world entirely for this. Simply
          copy /usr/src/sys/sys/soundcard.h to
          /usr/include/sys/soundcard.h would suffice. Few drivers also
          need recompilation, and this can be done via
          /usr/src/sys/modules/sound/.
          Support for 24bit hardware playback is beyond the scope of
          this changes. That would require spessific hardware driver
          changes.
        * Don't expect playing 9999999999hz is a wise decision. Be
          reasonable. The new feeder_rate implemention provide
          flexibility, not insanity. You can easily chew up your CPU
          with this kind of mind instability. Please use proper
          mosquito repellent device for this obvious cracked brain
          attempt. As for testing purposes, you can use (again)
          mplayer to generate / play with different sampling rate. Use
          something like "mplayer -af resample=192000:0:0 <files>".

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
Tested by:	multimedia@
2005-07-31 16:16:22 +00:00

160 lines
4.0 KiB
C

/*-
* Copyright (c) 1999 Cameron Grant <cg@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <dev/sound/pcm/sound.h>
SND_DECLARE_FILE("$FreeBSD$");
static u_int32_t fk_fmt[] = {
AFMT_U8,
AFMT_STEREO | AFMT_U8,
AFMT_S8,
AFMT_STEREO | AFMT_S8,
AFMT_S16_LE,
AFMT_STEREO | AFMT_S16_LE,
AFMT_U16_LE,
AFMT_STEREO | AFMT_U16_LE,
AFMT_S16_BE,
AFMT_STEREO | AFMT_S16_BE,
AFMT_U16_BE,
AFMT_STEREO | AFMT_U16_BE,
AFMT_S24_LE,
AFMT_STEREO | AFMT_S24_LE,
AFMT_U24_LE,
AFMT_STEREO | AFMT_U24_LE,
AFMT_S24_BE,
AFMT_STEREO | AFMT_S24_BE,
AFMT_U24_BE,
AFMT_STEREO | AFMT_U24_BE,
AFMT_S32_LE,
AFMT_STEREO | AFMT_S32_LE,
AFMT_U32_LE,
AFMT_STEREO | AFMT_U32_LE,
AFMT_S32_BE,
AFMT_STEREO | AFMT_S32_BE,
AFMT_U32_BE,
AFMT_STEREO | AFMT_U32_BE,
0
};
static struct pcmchan_caps fk_caps = {0, 1000000, fk_fmt, 0};
#define FKBUFSZ 4096
static char fakebuf[FKBUFSZ];
/* channel interface */
static void *
fkchan_init(kobj_t obj, void *devinfo, struct snd_dbuf *b, struct pcm_channel *c, int dir)
{
sndbuf_setup(b, fakebuf, FKBUFSZ);
return (void *)0xbabef00d;
}
static int
fkchan_free(kobj_t obj, void *data)
{
return 0;
}
static int
fkchan_setformat(kobj_t obj, void *data, u_int32_t format)
{
return 0;
}
static int
fkchan_setspeed(kobj_t obj, void *data, u_int32_t speed)
{
return speed;
}
static int
fkchan_setblocksize(kobj_t obj, void *data, u_int32_t blocksize)
{
return blocksize;
}
static int
fkchan_trigger(kobj_t obj, void *data, int go)
{
return 0;
}
static int
fkchan_getptr(kobj_t obj, void *data)
{
return 0;
}
static struct pcmchan_caps *
fkchan_getcaps(kobj_t obj, void *data)
{
return &fk_caps;
}
static kobj_method_t fkchan_methods[] = {
KOBJMETHOD(channel_init, fkchan_init),
KOBJMETHOD(channel_free, fkchan_free),
KOBJMETHOD(channel_setformat, fkchan_setformat),
KOBJMETHOD(channel_setspeed, fkchan_setspeed),
KOBJMETHOD(channel_setblocksize, fkchan_setblocksize),
KOBJMETHOD(channel_trigger, fkchan_trigger),
KOBJMETHOD(channel_getptr, fkchan_getptr),
KOBJMETHOD(channel_getcaps, fkchan_getcaps),
{ 0, 0 }
};
CHANNEL_DECLARE(fkchan);
struct pcm_channel *
fkchan_setup(device_t dev)
{
struct snddev_info *d = device_get_softc(dev);
struct pcm_channel *c;
c = malloc(sizeof(*c), M_DEVBUF, M_WAITOK);
c->methods = kobj_create(&fkchan_class, M_DEVBUF, M_WAITOK);
c->parentsnddev = d;
/*
* Fake channel is such a blessing in disguise. Using this,
* we can keep track prefered virtual channel speed without
* querying kernel hint repetitively (see vchan_create / vchan.c).
*/
c->speed = 0;
snprintf(c->name, CHN_NAMELEN, "%s:fake", device_get_nameunit(dev));
return c;
}
int
fkchan_kill(struct pcm_channel *c)
{
kobj_delete(c->methods, M_DEVBUF);
c->methods = NULL;
free(c, M_DEVBUF);
return 0;
}