Commit Graph

371 Commits

Author SHA1 Message Date
Ariff Abdullah
a1d444e140 MEGA Fixes / Cleanup
--------------------

- Seal the fate of long standing memory leak (4 years, 7 months) during
  pcm_unregister(). While destroying cdevs, scan / detect possible
  children and free its SLIST placeholder properly.
- Optimize channel allocation / numbering even further. Do brute cyclic
  checking only if the channel numbering screwed.
- Mega vchan create/destroy cleanup:
  o Implement pcm_setvchans() so everybody can use it freely instead
    of implementing their own, be it through sysctl or channel auto
    allocation.
  o Increase vchan creation/destruction resiliency:
    + it's possible to increase/decrease total vchans even during
      busy playback/recording. Busy channel will be left alone, untouched.
      Abusive test sample:
      # play whatever...
      #
         while : ; do
           sysctl hw.snd.pcm0.vchans=1
           sysctl hw.snd.pcm0.vchans=10
           sysctl hw.snd.pcm0.vchans=100
           sysctl hw.snd.pcm0.vchans=200
         done
      # Play something else, leave above loop running frantically.
    + Seal another 4 years old bug where it is possible to destroy (virtual)
      channel even when its cdevs being referenced by other process.
      The "First Come First Served" nature of dsp_clone() is the main
      culprit of this issue, and usually manifest itself as dangling
      channel <-> process association. Ensure that all of its cdevs
      are free from being referenced before destroying it (through
      ORPHAN_CDEVT() macross).

All these fixes (including previous fixes) will be MFCed, later.
2006-03-31 10:36:36 +00:00
Ariff Abdullah
9c271eba78 - Increase snddev refcount earlier while accessing through sysctl interface
to avoid possible device unregister race (impossible to reproduce, yet
  possible).
- Extra sanity check to ensure proper parent channel is being selected.
- Reset parent channel once all of its children gone.
2006-03-31 10:27:47 +00:00
Ariff Abdullah
844f9220aa Remove paranoid thread hijacking check. It cause wierd behaviour
(dangling channel - process association) especially in threaded
or fork()ed apps.
2006-03-30 06:17:03 +00:00
Ariff Abdullah
b422186846 We shouldn't really care about the return value of mixer_uninit(),
except EBUSY.
2006-03-22 20:50:04 +00:00
Ariff Abdullah
c17cb0c68f Pointer align should be generic enough to handle awkward byte size
especially for true 24bit format.
2006-03-22 00:34:17 +00:00
Ariff Abdullah
3fdb3676ba Apply more thorough fixes while dealing with device opening and closing:
- Determine open direction using 'flags', not 'mode'. This bug exist since
  past 4 years.
- Don't allow opening the same device twice, be it in a same or different
  direction.
- O_RDWR is allowed, provided that it is done by a single open (for example
  by mixer(8)) and the underlying hardware support true full-duplex operation.
- Do various paranoid checking in case other process/thread trying to hijack
  the same device twice (or more).

MFC after:	5 days
2006-03-21 06:35:48 +00:00
Ariff Abdullah
945510a039 Restore CHN_F_BUSY flag which was removed accidentally in previous commit. 2006-03-16 08:01:10 +00:00
Ariff Abdullah
7982e7a465 Fix severe 8bit integer overflow during channel creation and destruction,
especially for vchans. It turns out that channel numbering always depend
on d->devcount counter (which keep increasing), while PCMMKMINOR() truncate
everything to 8bit length. At some point the truncation cause the newly
created character device overlapped with the existence one, causing erratic
overall system behaviour and panic. Easily reproduce with something like:

	(Luckily, only root can reproduce this)

	while : ; do
		sysctl hw.snd.pcm0.vchans=200
		sysctl hw.snd.pcm0.vchans=100
	done

- Enforce channel/chardev numbering within 8bit boundary. Return E2BIG
  if necessary.
- Traverse d->channels SLIST and try to reclaim "free" counter during channel
  creation. Don't rely on d->devcount at all.
- Destroy vchans in reverse order.

Anyway, this is not the fault of vchans. It is just that vchans are so cute
and begging to be abused ;) . Don't blame her.

Old, hidden bugs.. sigh..

MFC after:	3 days
2006-03-16 04:12:49 +00:00
John Baldwin
de49f3252c Remove some dead code.
Coverity ID:	822
Found by:	Coverity Prevent
Reviewed by:	ariff
MFC after:	1 week
2006-02-23 19:23:55 +00:00
Alexander Leidinger
9d978cc757 Convert NULL checks into KASSERT (and move them before the first
dereferencing) since a NULL value would be a bug here.

Note: Both affected functions look very similar. A refactoring may
be beneficial.

CID:		483, 485
Found with:	Coverity Prevent(tm)
Discussed with:	ariff
MFC after:	5 days
2006-02-05 17:47:26 +00:00
Alexander Leidinger
c8c4c87d6a Fix some potential NULL pointer dereferences.
This is supposed to fix some Coverity Prevent errors (Ariff didn't
looked at the CID's (ENOTIME), I just told him that there are some problems
in function dsp_ioctl()).

CID:		215-218
Found with:	Coverity Prevent(tm)
Submitted by:	ariff
MFC after:	5 days
2006-01-29 16:48:41 +00:00
Ariff Abdullah
4a193ac907 Tune format scoring so (non)stereo format will get better chance
to be selected.
2006-01-29 01:32:37 +00:00
Joel Dahl
da8623eca0 Fix typos and clean up some comments.
Approved by:	ariff
2006-01-25 21:13:46 +00:00
Ariff Abdullah
14665331ab channel.c:
(1) Fix DMA alignment, based on bytes per sample.

feeder_rate.c:
	Handle strayed bytes (mostly caused by #1) better.

This DMA alignment issues are extremely hard to reproduce unless
the user happen to have a 32bit capable soundcards (ATI IXP) and
knowledgeable enough to force it to operate under pure 32bit
operations on both record and play directions.
2006-01-24 01:10:07 +00:00
Ariff Abdullah
d9bd844573 Various fixups:
feeder.h:
 feeder.c:
	- Implement scoring mechanisme to select best format for conversion.
	  This is actually part of newer format chaining procedures which
	  will be commited someday. Confusion during chaining process solved
	  by this scoring since it will try to reduce list of from/to formats
	  to a single, best format.
	  Related PR:	kern/91683
channel.c:
	- Simplify feeder building process since we have smarter format
	  chaining.

feeder_fmt.c:
	- Add few more sign conversion feeders for 24 and 32 bit format.

feeder_rate.c:
	- Force buffer / bytes allignment. Unaligned buffer may cause
	  panics during recording on pure 32bit sample format if it
	  involves feeder_rate as part of feeders chain.
	  Tested on: ATI IXP, force 32bit recording.

MFC after:	5 days
2006-01-22 15:06:49 +00:00
Ariff Abdullah
9ca45dd7dc Ruthless vchan speed workaround against the dreaded sb16 / sb16x. It appear
that nothing else using this weird 45k / 49k speed upper limit.
2006-01-20 03:46:02 +00:00
Ariff Abdullah
2fd8d3d84e Restore old compatibility of feeding directly into /dev/dsp at 8000 hz
while preserving the New World Order.

Discussed with:	[1] Michael W. Oliver <michael at gargantuan.com>
MFC after:	1 week

[1] http://lists.freebsd.org/pipermail/freebsd-multimedia/2006-January/003562.html
2006-01-16 11:07:15 +00:00
Ariff Abdullah
97efeca38d Workaround for sb16 behave poorly when running at 45000 hz while
vchan is enabled.

Reported by:	many sb16, AWE64 users.
MFC after:	1 week
2006-01-13 18:10:43 +00:00
Ariff Abdullah
e1e05d5d12 Add codec id support for Analog Device AD1986 AC'97 codec.
Submitted by:	UMENO Takashi <umeno at rr.iij4u.or.jp>
PR:		kern/80234
MFC after:	2 days
2006-01-07 05:20:46 +00:00
Ariff Abdullah
cc6882e1a4 Fix another xruns counting logic, this time, for recording. 2006-01-01 18:16:13 +00:00
Ariff Abdullah
c3ebbcbdf8 Fix LOR #174.
Tested with:	WITNESS, INVARIANTS and DIAGNOSTICS
2005-12-31 01:58:40 +00:00
Ariff Abdullah
f935ac6015 Disable frantic DMA update within few SNDCTL_DSP_* ioctl.
This should reduce huge playback / recording latency for
applications that try to act smarter and manage their own
buffering (XMMS, Skype, etc.).

Note to Skype + via8xxx users: Remove previous hackish
"hint.pcm.<unit>.via_dxs_disabled" from kernel hint and see
whether this changes cure all those annoying sound issues.
2005-12-30 07:33:28 +00:00
Ariff Abdullah
764907327e Underruns counting logic should be based on bufhard free space
and must be done after sndbuf_feed(), or any attempt to fill
up bufhard. This should fix false underruns counter.
2005-12-30 07:33:01 +00:00
Ariff Abdullah
eaf700837f Few codec such as Conexant CX20468-21 does have this control
register, although the only usable part is the mute bit.

Noticed by:	Hans Petter Selasky <hselasky@c2i.net>
2005-12-30 01:06:29 +00:00
Pyun YongHyeon
b7994e3488 Add codec ID for Avance Logic ALC203 2005-11-30 01:44:22 +00:00
Ariff Abdullah
187879feee Added mono to stereo and stereo to mono feeder functions for both
24 and 32 bit format.
2005-11-26 03:54:17 +00:00
Ariff Abdullah
b327ee5148 Added codec id for Avance Logic (ALC250) 2005-11-26 03:51:25 +00:00
Alexander Kabaev
fcf97578ff Unbreak kernel builds.
Submitted by:	arr
2005-11-15 04:19:27 +00:00
Ariff Abdullah
720289b2cd Update my email address, so people know where the exact /
proper / correct place to bug me.

Approved by:	netchild (mentor)
2005-11-14 18:37:59 +00:00
Ariff Abdullah
bd2ce91cdc From luigi:
This one simply tries to simplify the logic to select the
	buffer sizes. I am not sure it is necessary but the code
	seems a bit more readable to me. And at least i have tried
	to document how the buffer sizes are computed.

Thanks to luigi for deciphering one of the most cryptic part of
sound driver.

Submitted by:	luigi
Approved by:	netchild (mentor)
2005-11-14 18:21:23 +00:00
Ariff Abdullah
ee43f8a667 From luigi:
In SNDCTL_DSP_SETFRAGMENT, if you specify both read and
	write channels, the existing code first acts on the
	read channel, but as a side effect it updates the
	arguments (maxfrags, fragsz) passed by the caller according
	to acceptable values for the read channel, and then uses the
	modified values to act on the write channel.
	The problem with this approach is that, given a
	(maxfrags, fragsz) user-specified value, the actual
	values computed by the read and write channels may differ:
	e.g. the read channel might want to allocate more fragments
	than what the user specified because it has no side-effects
	on the delay and it helps in case of slow readers,
	whereas the write channel needs to use as few fragments
	as possible to keep the audio latency low (very important
	with telephony apps).

	This patch stores the values computed by the read channel
	into temproary variables so the write channel will use
	the actual arguments of the ioctl.

	This patch is very helpful with telephony apps such as asterisk.

Submitted by:	luigi
Approved by:	netchild (mentor)
2005-11-14 18:20:47 +00:00
Ariff Abdullah
801389376f ac97.c:
- Added new codec id for CX20468-21 and VIA1617A.
   Submitted by:	Chen Lihong <lihong.chen@gmail.com>
 - Re-enable SOUND_MIXER_IGAIN, but set the default level as 0 (mute)
   Suggested by:	luigi

mixer.c:
 - Set default value for SOUND_MIXER_IGAIN as 0 (mute) to avoid
   feedback problems on some laptops (was disabled by jhb during
   ac97.c revision 1.42).

Approved by:	netchild (mentor)
2005-11-14 18:19:33 +00:00
Ariff Abdullah
8be20fbe2a Appropriate NULL pointer checking to avoid mysterious panic during
device cloning.

Approved by:	netchild (mentor)
2005-11-03 08:19:04 +00:00
Dag-Erling Smørgrav
85cc3851ff Add some safeguards to AIOSFMT:
- Return EINVAL if play_format or rec_format is set but the corresponding
   sample rate is 0.

 - Don't try to set the playback or recording format to 0.  Previously,
   issuing an AIOSFMT ioctl with an all-zeroes snd_chan_param would
   trigger a KASSERT in chn_fmtchain(); I'm unsure about the effects on
   a kernel without INVARIANTS.  After this commit, issuing AIOSFMT with
   an all-zeroes snd_chan_param is equivalent to issuing AIOGFMT.

MFC after:	2 weeks
2005-10-30 10:03:11 +00:00
Ariff Abdullah
d45d1f2077 Fix vchan speed for hardware with discrete (non-continuous)
sampling rate:
- Improve vchan chn_setspeed() strategy. Try to avoid FEEDER_RATE
  on parent channel if the requested value is not supported
  by the hardware.
- Fix vchan default speed calculation. In any case, vchan should
  rely on parent bufsoft speed instead of bufhard since it is
  possible that the entire feeder chain might involve FEEDER_RATE.
  This is possible under extreme, rare condition if the above
  chn_setspeed() strategy failed.

Approved by:	netchild (mentor)
2005-10-18 21:33:51 +00:00
Ariff Abdullah
3f3c2c43b0 Added missing comma. This fixes compilation if we need to enable
RATE_ASSERT debug macro.

Approved by:	netchild (mentor)
2005-10-18 21:18:47 +00:00
Alexander Leidinger
d793e09c95 The cmi9739_patch function which is referenced by ac97.c (rev. 1.56) now...
Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
Pointy hat to:	netchild (for not committing it with rev. 1.56 of ac97.c)
2005-10-02 15:50:22 +00:00
Alexander Leidinger
28ef3fb011 sys/dev/sound/pcm/sndstat.c:
* General spl* cleanup. It doesn't serve any purpose anymore.
   * Nuke sndstat_busy(). Addition of sndstat_acquire() /
     sndstat_release() for sndstat exclusive access. [1]

sys/dev/sound/pcm/sound.c:
   * Remove duplicate SLIST_INIT()
   * Use sndstat_acquire() / release() to lock / release the entire
     sndstat during pcm_unregister(). This should fix LOR #159 [1]

sys/dev/sound/pcm/sound.h:
   * Definition of SD_F_SOFTVOL (part of feeder volume)
   * Nuke sndstat_busy(). Addition of sndstat_acquire() /
     sndstat_release() for exclusive sndstat access. [1]

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
LOR:		159 [1]
Discussed with:	yongari [1]
2005-10-02 15:43:57 +00:00
Alexander Leidinger
62340837c3 General spl* cleanup. It doesn't serve any purpose anymore.
Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
2005-10-02 15:39:07 +00:00
Alexander Leidinger
cb44f623ec sys/dev/sound/pcm/ac97.c:
* Added codec id for CMI9761.
   * feeder_volume *whitelist* through ac97_fix_volume()

sys/dev/sound/pcm/ac97.h:
   * Added AC97_F_SOFTVOL definition.

sys/dev/sound/pcm/channel.c:
   * Slight changes for chn_setvolume() to conform with OSS.
   * FEEDER_VOLUME is now part of feeder building process.

sys/dev/sound/pcm/mixer.c:
   * General spl* cleanup. It doesn't serve any purpose anymore.
   * Main hook for feeder_volume.

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
Tested by:	multimedia@
2005-10-02 15:37:40 +00:00
Alexander Leidinger
4406886f5e Soft volume implementation for audio devices without pcm mixer controller.
Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
Tested by:	multimedia@
2005-10-02 15:31:03 +00:00
Pyun YongHyeon
005a5d42fa Fix module unload panic which was caused by missing sx lock release.
While I'm here add KASSERT(9) to notify failure of SYSUNINIT handler.

Reported by:	Ben Kaduk < minimarmot AT gmail DOT com >
Tested by:	Ben Kaduk < minimarmot AT gmail DOT com >
2005-09-14 01:34:13 +00:00
Alexander Leidinger
831a62e7e5 - Fix the locking in dsp.c to prevent a LOR (AFAIK not on the LOR page).
- Remove an assertion in sound.c, it's not needed (and causes a panic now).
  From the conversation via mail between glebius and Ariff:
  ---snip---
  > Well, but which mutex protects now? Do we own anything else
  > in pcm_chnalloc()? I see some queue(4) macros in pcm_chnalloc(),
  > they should be protected, shouldn't they?
  Queue insertion/removal occur during
     1) driver loading (which is pretty much single thread /
        sequential) or unloading (mutex protected, bail out if there is
        any channel with refcount > 0 or busy).
     2) vchan_create()/destroy(), (which is *sigh* quite complicated), but
        somehow protected by 'master'/parent channel mutex. Other
        thread cannot add/remove vchan (or even continue traversing
        that queue) unless it can acquire parent channel mutex.
---snip---

Fix the locking in dsp.c to prevent a LOR (AFAIK not on the LOR page).

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
Tested with:	INVARIANTS[1] and DIAGNOSTICS[2]
Tested by:	netchild [1,2], David Reid <david@jetnet.co.uk> [1]
2005-09-12 18:33:33 +00:00
Alexander Leidinger
97d69a9620 - channel.h
* New definition CHN_F_HAS_VCHAN.
- channel.c
  * Use CHN_F_HAS_VCHAN to mark channel with vchan capability instead
    of relying on SLIST_EMPTY(&channel->children) == true for better
    clarification and future possible usages of children (like
    'slave' channel).
  * Various fixes, including blocksize / format bps allignment,
    better 24bit seeking (mplayer, others).
  * Improve format chain building, it's now possible to record something
    to a format non-native to the soundcard through various feeder format
    converters or to higher sampling rate. This also gains another feature,
    like doing vchan mixing on non s16le soundcard such as sb8.
- sound.c
  * Increase robustness within various function that handle vchan
    creation / termination (these function need a total rewrite, but
    that would cause other major rewrite within various places too!).
    As far as its robustness can be guaranteed, leave it as is.
  * Optimize channel ordering, prefer *real* hardware playback
    channels over virtual channels. cat /dev/sndstat should look
    better.
  * Increase sndstat verbosity to include bufsoft/bufhard allocation.
- vchan.c
  * Fix LOR 119.
    - http://sources.zabbadoz.net/freebsd/lor.html#119
  * Reorder / increase robustness of vchan_create() / destroy().
    Enforce destroy_dev() during destroy operation, fix possible
    panic / dangling character device.
    - http://lists.freebsd.org/pipermail/freebsd-current/2005-May/050308.html
  * Tolerate a little bit more during mixing process, this should help
    non s16le soundcards.

Note: Recoring in a non-native rate/format may result in overruns. A friendly
      application is wavrec from audio/wavplay. The problem is under
      investigation.

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
2005-09-10 18:10:31 +00:00
Alexander Leidinger
a423446c40 Release lock for a while during chn_reset() / pcm_chnalloc() operation
while malloc()ing, this fixes LOR 129.

See
 - http://lists.freebsd.org/pipermail/freebsd-current/2005-June/051157.html
 - http://lists.freebsd.org/pipermail/freebsd-current/2005-August/054620.html
 - http://sources.zabbadoz.net/freebsd/lor.html#129

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
2005-09-10 17:51:38 +00:00
Alexander Leidinger
5cfcc28b60 - fake.c
* Add missing A_LAW / MU_LAW format.
- feeder.c
  * Fix format chain building. Traverse backward instead of forward
    during format chainning.
- feeder_fmt.c
  * Add missing alaw/mulaw converter.
  * Add 16 -> 24/32bit converter.
  * whitespace cleanup.
- sound.h
  * alaw / mulaw are member of AFMT_8BIT.

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
2005-09-10 17:47:39 +00:00
Alexander Leidinger
8633619643 - Few buggy codecs (STAC9704, probably others) return inconsistent
ac97_rdcd() value. Enable aggresive workaround.
- Fix mixer resolution detection for 5/6 bit register, carefully not to
  overflow others.

PR:		84728
Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
2005-09-10 17:42:59 +00:00
Robert Watson
6a113b3de7 Merge the dev_clone and dev_clone_cred event handlers into a single
event handler, dev_clone, which accepts a credential argument.
Implementors of the event can ignore it if they're not interested,
and most do.  This avoids having multiple event handler types and
fall-back/precedence logic in devfs.

This changes the kernel API for /dev cloning, and may affect third
party packages containg cloning kernel modules.

Requested by:	phk
MFC after:	3 days
2005-08-08 19:55:32 +00:00
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
Alexander Leidinger
fe435202da * Slightly new method to detect mixer capabilities and resolution.
This mostly to help CT4730, but apparently it does help other
  cards too (especially via8233x). This probably need further test
  and confirmation from other people with ac97 cards other than via
  / es137x.
* Aggresive dac power wake up call, again, to help CT4730 (and
  probably others).

Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my>
Tested by:	multimedia@
2005-07-31 14:28:31 +00:00