sound: Handle unavailable devices in various OSS IOCTLs

mixer(8)'s -a option is used to print information about all mixer
devices in the system. To do this, it loops from 0 to
mixer_get_nmixers(), and tries to open "/dev/mixer%d". However, this
approach doesn't work when there are disabled/unregistered mixers in the
system, or when an audio device simply doesn't have a mixer.

mixer_get_nmixers() calls SNDCTL_SYSINFO and returns
oss_sysinfo->nummixers, whose value is the number of currently _enabled_
mixers only. Taking the bug report mentioned below (277615) as an
example, suppose a system with 8 mixer devices total, but 3 of them are
either disabled or non-existent, which means they will not show up under
/dev, meaning we have 5 enabled mixer devices, which is also what the
value of oss_sysinfo->nummixers will be. What mixer(8) will do is loop
from 0 to 5 (instead of 8), and start calling mixer_open() on
/dev/mixer0, up to /dev/mixer4, and as is expected, the first call will
fail right away, hence the error shown in the bug report.

To fix this, modify oss_sysinfo->nummixers to hold the value of the
maximum unit in the system, which, although not necessarily "correct",
is more intuitive for applications that will want to use this value to
loop through all mixer devices.

Additionally, notify applications that a device is
unavailable/unregistered instead of skipping it. The current
implementations of SNDCTL_AUDIOINFO, SNDCTL_MIXERINFO and
SNDCTL_CARDINFO break applications that expect to get information about
a device that is skipped. Related discussion can be found here:
https://reviews.freebsd.org/D45135#1029526

It has to be noted, that other applications, apart from mixer(8), suffer
from this.

PR: 277615
Sponsored by: The FreeBSD Foundation
MFC after: 1 day
Reviewed by: dev_submerge.ch
Differential Revision: https://reviews.freebsd.org/D45256

sound: Separate implementations for SNDCTL_AUDIOINFO[_EX] and SNDCTL_ENGINEINFO

FreeBSD's implementation of SNDCTL_AUDIOINFO[_EX] and SNDCTL_ENGINEINFO
does not exactly work as intended. The problem is essentially that both
IOCTLs return the same information, while in fact the information
returned currently by dsp_oss_audioinfo() is what _only_
SNDCTL_ENGINEINFO is meant to return.

This behavior is also noted in the OSS manual [1] (see bold paragraph in
"Audio engines and device files" section), but since e8c0d15a64fa
("sound: Get rid of snd_clone and use DEVFS_CDEVPRIV(9)") we can
actually fix this, because we now expose only a single device for each
soundcard, and create the engines (channels) internally.
SNDCTL_ENGINEINFO will now report info about all channels in a given
device, and SNDCTL_AUDIOINFO[_EX] will only report information about
/dev/dspX.

To make this work, we also have to modify the SNDCTL_SYSINFO IOCTL to
report the number of audio devices and audio engines correctly.

While here, modernize the minimum and maximum channel counting in both
SNDCTL_AUDIOINFO[_EX] and SNDCTL_ENGINEINFO. Currently these IOCTLs will
report only up to 2 channels, which is no longer the case.

[1] http://manuals.opensound.com/developer/SNDCTL_AUDIOINFO.html

PR: 246231, 252761
Sponsored by: The FreeBSD Foundation
MFC after: 1 day
Reviewed by: dev_submerge.ch
Differential Revision: https://reviews.freebsd.org/D45164

sound: Add missing oss_mixerinfo devnode and legacy_device fields

They are missing from soundcard.h and are in fact used by some
applications, such as OSS' ossinfo(1):
http://manuals.opensound.com/developer/ossinfo.c.html

The new size for filler is chosen according to the most recent official
version of soundcard.h, which includes those 2 fields.

Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Reviewed by: dev_submerge.ch
Differential Revision: https://reviews.freebsd.org/D45137

sound: Remove nmix variable from mixer_oss_mixerinfo()

nmix is used to compare against oss_mixerinfo->dev, which is a
user-supplied value to select the mixer device (if not -1, in which case
we'll select the default one) we want to fetch the information of. It is
also used to set oss_mixerinfo->dev in case it is -1.

However, nmix is at best redundant, since we have the loop counter
already (i), and confusing at worst.

For example, suppose a system with 3 mixer devices. We call
SNDCTL_MIXERINFO with oss_mixerinfo->dev=1, meaning we want to get
information for /dev/mixer1. Suppose /dev/mixer0 detaches while inside
the loop, so we'll hit the loop's "continue" case, and nmix won't get
incremented (i.e will stay 0 for now). At this point nmix counts 1
device less, so when it reaches 1, we'll be fetching /dev/mixer2's
information instead of /dev/mixer1's.

This is also true in case the mixer device disappears prior to the call
to mixer_oss_mixerinfo().

Simply remove nmix and use the loop counter to both set
oss_mixerinfo->dev and check against it in case a non -1 value is
supplied.

Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Reviewed by: dev_submerge.ch
Differential Revision: https://reviews.freebsd.org/D45135

sound: Use nitems() where possible

No functional change intended.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: markj, emaste
Differential Revision: https://reviews.freebsd.org/D45014

sound: Retire unit.*

The unit.* code is largely obsolete and imposes limits that are no
longer needed nowadays.

- Capping the maximum allowed soundcards in a given machine. By default,
the limit is 512 (snd_max_u() in unit.c), and the maximum possible is
2048 (SND_UNIT_UMAX in unit.h). It can also be tuned through the
hw.snd.maxunit loader(8) tunable. Even though these limits are large
enough that they should never cause problems, there is no need for
this limit to exist in the first place.
- Capping the available device/channel types. By default, this is 32
(snd_max_d() in unit.c). However, these types are pre-defined in
pcm/sound.h (see SND_DEV_*), so the cap is unnecessary when we know
that their number is constant.
- Capping the number of channels per-device. By default, the limit 1024
(snd_max_c() in unit.c). This is probably the most problematic of the
limits mentioned, because this limit can never be reached, as the
maximum is hard-capped at either hw.snd.maxautovchans (16 by default),
or SND_MAXHWCHAN and SND_MAXVCHANS.

These limtits are encoded in masks (see SND_U_MASK, SND_D_MASK,
SND_C_MASK in unit.h) and are used to construct a bitfield of the form
[dsp_unit, type, channel_unit] in snd_mkunit() which is assigned to
pcm_channel->unit.

This patch gets rid of everything unit.*-related and makes a slightly
different use of the "unit" field to only contain the channel unit
number. The channel type is stored in a new pcm_channel->type field, and
the DSP unit number need not be stored at all, since we can fetch it
from device_get_unit(pcm_channel->dev). This change has the effect that
we no longer need to impose caps on the number of soundcards,
device/channel types and per-device channels. As a result the code is
noticeably simplified and more readable.

Apart from the fact that the hw.snd.maxunit loader(8) tunable is also
retired as a side-effect of this patch, sound(4)'s behavior remains the
same.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: dev_submerge.ch
Differential Revision: https://reviews.freebsd.org/D44912

sound: Wrap dsp_clone() and mixer_clone() with bus_topo_lock()

Make sure that the softc isn't freed in between the checks.

Sponsored by: The FreeBSD Foundation
MFC after; 1 day
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D44991

sound: Fix NULL dereference in dsp_clone() and mixer_clone()

If we only have a single soundcard attached and we detach it right
before entering [dsp|mixer]_clone(), there is a chance pcm_unregister()
will have returned already, meaning it will have set snd_unit to -1, and
thus devclass_get_softc() will return NULL here.

While here, 1) move the calls to dsp_destroy_dev() and mixer_uninit()
below the point where we unset SD_F_REGISTERED, and 2) follow what
mixer_clone() does and make sure we don't use a NULL d->dsp_dev in
dsp_clone().

Reported by: KASAN
Sponsored by: The FreeBSD Foundation
MFC after: 1 day
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D44924

sound: Remove PCMMINOR()

It's a NO-OP.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: markj, emaste
Differential Revision: https://reviews.freebsd.org/D44854

sound: Call device_get_name() and device_get_unit() only once in mixer_init()

No functional change intended.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: markj, emaste
Differential Revision: https://reviews.freebsd.org/D44840

sound: Implement asynchronous device detach

Hot-unplugging a sound device, such as a USB sound card, whilst being
consumed by an application, results in an infinite loop until either the
application closes the device's file descriptor, or the channel
automatically times out after hw.snd.timeout seconds. In the case of a
detach however, the timeout approach is still not ideal, since we want
all resources to be released immediatelly, without waiting for N seconds
until we can use the bus again.

The timeout mechanism works by calling chn_sleep() in chn_read() and
chn_write() (see pcm/channel.c) in order to send the thread to sleep,
using cv_timedwait_sig(). Since chn_sleep() sets the CHN_F_SLEEPING flag
while waiting for cv_timedwait_sig() to return, we can test this flag in
pcm_unregister() (called during detach) and wakeup the sleeping
thread(s) to immediately kill the channel(s) being consumed.

Sponsored by: The FreeBSD Foundation
MFC after: 2 months
PR: 194727
Reviewed by: dev_submerge.ch, bapt, markj
Differential Revision: https://reviews.freebsd.org/D43545

Revert "sound: Implement asynchronous device detach"

This reverts commit 9eff58c6d52b66eb8abe7f724dabcd804a566df4.

We are reverting dc831e93bad6 ("sound: Get rid of snd_clone and use
DEVFS_CDEVPRIV(9)"), so revert this commit as well since it depends
dc831e93bad6.

sound: Implement asynchronous device detach

Hot-unplugging a sound device, such as a USB sound card, whilst being
consumed by an application, results in an infinite loop until either the
application closes the device's file descriptor, or the channel
automatically times out after hw.snd.timeout seconds. In the case of a
detach however, the timeout approach is still not ideal, since we want
all resources to be released immediatelly, without waiting for N seconds
until we can use the bus again.

The timeout mechanism works by calling chn_sleep() in chn_read() and
chn_write() (see pcm/channel.c) in order to send the thread to sleep,
using cv_timedwait_sig(). Since chn_sleep() sets the CHN_F_SLEEPING flag
while waiting for cv_timedwait_sig() to return, we can test this flag in
pcm_unregister() (called during detach) and wakeup the sleeping
thread(s) to immediately kill the channel(s) being consumed.

Sponsored by: The FreeBSD Foundation
MFC after: 2 months
PR: 194727, 278055, 202275, 220949, 272286
Reviewed by: dev_submerge.ch, markj
Differential Revision: https://reviews.freebsd.org/D43545

sys: Remove SND_DECLARE_FILE

Reviewed by: kbowling, imp, emaste
Differential Revision: https://reviews.freebsd.org/D41499

sys: Remove $FreeBSD$: sound driver version

Remove /SND_DECLARE_FILE\("\$FreeBSD\$"\);/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

sound: test PCM_REGISTERED before PCM_DETACHING

PCM_REGISTERED(d) tests that d is not NULL, so perform that check first
as we may have cases where devclass_get_softc has a null entry.

PR: 262671
Reviewed by: hselasky
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34648

Implement the SOUND_MIXER_WRITE_MUTE and SOUND_MIXER_READ_MUTE ioctl(9)s.

These two ioctls are not part of the current version of OSS and were
considered obsolete. However, their behaviour is not the same as their
old one, so this implementation is specific to FreeBSD.

Older OSS versions had the MUTE ioctls take and return an integer with
a value of 0 or 1, which meant that the _whole_ mixer is unmuted or
muted respectively. In my implementation, the ioctl takes and returns
a bitmask that tells us which devices are muted.

This allows us to mute and unmute only the devices we want, instead of the
whole mixer. The bitmask works the same way as in DEVMASK, RECMASK and
RECSRC.

Integrated the hardware volume feature with the new mute system.

Submitted by: Christos Margiolis <christos@freebsd.org>
Differential Revision: https://reviews.freebsd.org/D31130
MFC after: 1 week
Sponsored by: NVIDIA Networking

sound: clean up empty lines in .c and .h files

Implement new mixer API to return the device pointer based on the mixer pointer.

MFC after: 1 week
Sponsored by: Mellanox Technologies

Change default microphone level from 0 to 25.

Discussed with: Horse Ma <Shichun.Ma@dell.com>
MFC after: 1 week
Sponsored by: Mellanox Technologies

Implement a detaching flag for the sound(4) subsystem to take
appropriate actions when we are trying to detach an audio device,
but cannot because someone is using it.

This avoids applications having to wait for the DSP read data
timeout before they receive any error indication.
Tested with virtual_oss(8).

Remove some unused definitions while at it.

PR: 194727
MFC after: 1 week
Sponsored by: Mellanox Technologies

Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718

Update modify counter when setting a mixer control.

PR: 229969
MFC after: 1 week

sys/dev: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Make all PCM core sysctls tunable and remove redundant TUNABLE()
statements. This allows for setting all PCM core parameters in the
kernel environment through loader.conf(5) or kenv(1) which is useful
for pluggable PCM devices like USB audio devices which might be
plugged after that sysctl.conf(5) is executed.

Remove check for obsolete FreeBSD versions

PR: 194517
Submitted by: François Tigeot <ftigeot@wolfpond.org>

Add support for SOUND_MIXER_INFO IOCTL, used by gstreamer.

Submitted by: Dmitry Luhtionov <dmitryluhtionov@gmail.com>
MFC after: 2 weeks

Pull in r267961 and r267973 again. Fix for issues reported will follow.

Revert r267961, r267973:

These changes prevent sysctl(8) from returning proper output,
such as:

1) no output from sysctl(8)
2) erroneously returning ENOMEM with tools like truss(1)
or uname(1)
truss: can not get etype: Cannot allocate memory

Extend the meaning of the CTLFLAG_TUN flag to automatically check if
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after: 2 weeks
Sponsored by: Mellanox Technologies

Add support for mute buttons on USB audio devices and
use the hwvol interface to adjust the mixer settings.

MFC after: 1 week

Add support for buttons on USB audio devices,
like Volume Up and Volume Down.

Reviewed by: mav @
MFC after: 1 week

Remove direct access to si_name.

Code should just use the devtoname() function to obtain the name of a
character device. Also add const keywords to pieces of code that need it
to build properly.

MFC after: 2 weeks

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

MFC r202150, r202170:
Make OSS_GETVERSION ioctl really work. It has 'M' group, not 'P',
as different nearby ones, and was grabbed by MIXER_xxx() handler.

While there, replace '(cmd & MIXER_xxx(0)) == MIXER_xxx(0)' expressions
with more correct '(cmd & ~0xff) == MIXER_xxx(0)'. Use of bit operations
to compare numeric fields doesn't looks sane.

MFC r202166:
Make default recording source choosing more intelligent.
Change default recording level from 0 to 75.
It should increase chances for things to work just out of the box.

Make default recording source choosing more intelligent.
Change default recording level from 0 to 75.
It should increase chances for things to work just out of the box.

Make OSS_GETVERSION ioctl really work. It has 'M' group, not 'P',
as different nearby ones, and was grabbed by MIXER_xxx() handler.

While there, replace '(cmd & MIXER_xxx(0)) == MIXER_xxx(0)' expressions
with more correct '(cmd & ~0xff) == MIXER_READ(0)'. Use of bit operations
to compare numeric fields doesn't looks sane.

MFC after: 1 month

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.

OSS tools expect EINVAL for unsupported ioctls, but not ENXIO.

Import some new constants and structures fields from OSSv4.
Implement some OSSv4 ioctls to make ossinfo tool work and print
something reasonable.

Bring in USB4BSD, Hans Petter Selasky rework of the USB stack
that includes significant features and SMP safety.

This commit includes a more or less complete rewrite of the *BSD USB
stack, including Host Controller and Device Controller drivers and
updating all existing USB drivers to use the new USB API:

1) A brief feature list:

- A new and mutex enabled USB API.

- Many USB drivers are now running Giant free.

- Linux USB kernel compatibility layer.

- New UGEN backend and libusb library, finally solves the "driver
unloading" problem. The new BSD licensed libusb20 library is fully
compatible with libusb-0.1.12 from sourceforge.

- New "usbconfig" utility, for easy configuration of USB.

- Full support for Split transactions, which means you can use your
full speed USB audio device on a high speed USB HUB.

- Full support for HS ISOC transactions, which makes writing drivers
for various HS webcams possible, for example.

- Full support for USB on embedded platforms, mostly cache flushing
and buffer invalidating stuff.

- Safer parsing of USB descriptors.

- Autodetect of annoying USB install disks.

- Support for USB device side mode, also called USB gadget mode,
using the same API like the USB host side. In other words the new
USB stack is symmetric with regard to host and device side.

- Support for USB transfers like I/O vectors, means more throughput
and less interrupts.

- ... see the FreeBSD quarterly status reports under "USB project"

2) To enable the driver in the default kernel build:

2.a) Remove all existing USB device options from your kernel config
file.

2.b) Add the following USB device options to your kernel configuration
file:

# USB core support
device usb2_core

# USB controller support
device usb2_controller
device usb2_controller_ehci
device usb2_controller_ohci
device usb2_controller_uhci

# USB mass storage support
device usb2_storage
device usb2_storage_mass

# USB ethernet support, requires miibus
device usb2_ethernet
device usb2_ethernet_aue
device usb2_ethernet_axe
device usb2_ethernet_cdce
device usb2_ethernet_cue
device usb2_ethernet_kue
device usb2_ethernet_rue
device usb2_ethernet_dav

# USB wireless LAN support
device usb2_wlan
device usb2_wlan_rum
device usb2_wlan_ral
device usb2_wlan_zyd

# USB serial device support
device usb2_serial
device usb2_serial_ark
device usb2_serial_bsa
device usb2_serial_bser
device usb2_serial_chcom
device usb2_serial_cycom
device usb2_serial_foma
device usb2_serial_ftdi
device usb2_serial_gensa
device usb2_serial_ipaq
device usb2_serial_lpt
device usb2_serial_mct
device usb2_serial_modem
device usb2_serial_moscom
device usb2_serial_plcom
device usb2_serial_visor
device usb2_serial_vscom

# USB bluetooth support
device usb2_bluetooth
device usb2_bluetooth_ng

# USB input device support
device usb2_input
device usb2_input_hid
device usb2_input_kbd
device usb2_input_ms

# USB sound and MIDI device support
device usb2_sound

2) To enable the driver at runtime:

2.a) Unload all existing USB modules. If USB is compiled into the
kernel then you might have to build a new kernel.

2.b) Load the "usb2_xxx.ko" modules under /boot/kernel having the same
base name like the kernel device option.

Submitted by: Hans Petter Selasky hselasky at c2i dot net
Reviewed by: imp, alfred

- Import the HEAD csup code which is the basis for the cvsmode work.

Remove unit2minor() use from kernel code.

When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.

We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().

Reviewed by: kib

Last (again ?!?) major commit for RELENG_7, featuring total Giant
eradication in/from userland path, countless locking fixes, etc.

- General sleep call through msleep(9) has been converted to condvar(9)
with better consistencies.
- Heavily guard every possible "slow path" entries (open(), close(),
few ioctl()s, sysctls), but once it entering "fast path" (io, interrupt
started), they are free to fly on their own.
- Rearrange locking sequences, resulting better concurrency and
serialization. Large part doesn't even need locking at all, and will be
removed in future. Less clutter, except in few places due to lock
ordering.
- Anonymous mixer object creation/deletion to simplify mixer handling
beyond typical mixer ioctls.
Submitted by: chibis (with modifications)
- Add few mix_[get|set|..] functions to avoid calling mixer_ioctl()
directly using cryptic arguments.
- Locking fixes to avoid possible deadlock with (still under Giant) USB.
- Better simplex/duplex device handling.
- Recover mmap() functionality for recording, which has been lost
since 2.2.x - 3.x (the introduction of newpcm). Full-duplex mmap still
doesn't work (due to VM/page design), but people still can mmap
both by opening each direction separately. mmaped playback is guarantee
to work either way.
- New sysctl: "hw.snd.compat_linux_mmap" to allow PROT_EXEC page
mapping, due to recent changes in linux compatibility layer which
require it. All linux applications that using sound + mmap() (mostly games)
require this to be enabled. Disabled by default.
- Other goodies.. too many, that will increase releng7 shareholder value
and make users of releng6 (and below) cry ;)

* This commit should be atomic. If anything goes wrong (not counting problem
originated from elsewhere), I will not hesitate to revert everything back
within 12 hours. This substantial changes itself not a rocket science
and the process has begun for almost 2 years, and lots of incremental
changes are already in place during that period of time.
* Some issues does occur in snd_emu10kx (note the 'x') due to various
internal locking issues and it is currently being worked on by chibis.

Tested by: chibis (Yuriy Tsibizov), joel, Alexandre Vieira,
many innocent souls...

Insert NULL pointer checking around devclass_get_maxunit(pcm_devclass, ..) .
Things can get ugly without it due to uninitialized class. RELENG_6 need
a simmilar, but different treatment as well.

err.. perhaps we should teach devclass_get_maxunit() to return -1 ?

MFC after: 1 day

Last major commit and updates for RELENG_7:

- Rework the entire pcm_channel structure:
* Remove rarely used link placeholder, instead, make each pcm_channel
as head/link of each own/each other. Unlock - Lock sequence due to
sleep malloc has been reduced.
* Implement "busy" queue which will contain list of busy/active
channels. This greatly reduce locking contention for example while
servicing interrupt for hardware with many channels or when virtual
channels reach its 256 peak channels.

- So I heard you like v chan ... O RLY?
Welcome to Virtual **Record** Channels (vrec, rec vchans, vchans for
recording, Rec-Chan, you decide), the ultimate solutions for your
nagging O_RDWR full-duplex wannabe (note: flash plugins) monopolizing
single record channel causing EBUSY. Vrec works exactly like Vchans
(or, should I rename it to "Vplay" :) , except that it operates on the
opposite direction (recording). Up to 256 vrecs (like vchans) are
possible.

Notes:
* Relocate dev.pcm.%d.{vchans,vchanformat,vchanrate} to each of its
respective node/direction:
dev.pcm.%d.play.* for "play" (cdev = dsp%d.vp%d)
dev.pcm.%d.rec.* for "record" (cdev = dsp%d.vr%d)
* Don't expect that it will magically give you ability to split
"recording source" (eg: 1 channel for cdrom, 1 channel for mic,
etc). Just admit that you only have a *single* recording source /
channel. Please bug your hardware vendor instead :)

- Bump maxautovchans from 4 to 16. For a full-fledged multimedia
desktop/workstation with too many soundservers installed (esound,
artsd, jackd, pulse/polypaudio, ding-dong pling plong mudkip fuh fuh,
etc), 4 seems inadequate. There will be no memory penalty here, since
virtual channels are allocate only by demand.

- Nuke/Rework the entire statically created cdev entries. Everything is
clonable through snd own clone manager which designed to withstand many
kind of abusive devfs droids such as:
* while : ; do /bin/test -e /dev/dsp ; done
* jot 16777216 0 | while read x ; do ls /dev/dsp0.$x ; done
* hundreds (could be thousands) concurrent threads/process opening
"/dev/dsp" (previously, this might result EBUSY even with just
3 contesting threads/procs).
o Reusable clone objects (instead of creating new one like there's no
tomorrow) after certain expiration deadline. The clone allocator will
decide whether to reuse, share, or creating new clone.
o Automatic garbage collector.

- Dynamic unit magic allocator. Maximum attached soundcards can be tuned
using tunable "hw.snd.maxunit" (Default to 512). Minimum is 16, and
maximum is 2048.

- ..other fixes, mostly related to concurrency issues.

joel@ will do the manpage updates on sound(4).

Have fun.

Revert busy refcount back to int. As a side note, multiple open
is still (and always) possible and does not change previous behaviour.

Requested by: netchild

No need to track every closing instance, and put busy counter to rest
in its single bit coffin.

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.

MFP4 (109713):
Add OSS_GETVERSION ioctl for compatibility.

Some ports expect this and fail to compile on -current ATM.

Submitted by: ryanb

The addition of few more 32bit integer into struct snd_mixer causing
an accidental MIXER_SIZE overflow. Use 8bit integer instead of 32bit
to reduce the kludge size.

Noticed by: tegge

Fix pointer dereference before NULL pointer checking.

Noticed by: netchild
CID: 243889
Found by: Coverity Prevent (TM)

Various fixups, especially for the upcomming High Definition Audio
commit.

1) sys/dev/sound/pcm/sound.h
sys/dev/sound/pcm/channel.c
* Be more specific: SD_F_SOFTVOL -> SD_F_SOFTPCMVOL
2) sys/dev/sound/pcm/mixer.[ch]
* Implement
mix_setparentchild()
mix_setrealdev()
mix_getparent()
mix_getchild()
The purpose of these functions is implement relative volume
adjustment, such as to tie two or more mixer device into a
single logical device. Usefull for the upcoming HDA driver
and few AC97 codec (such as AD1981B) where the master volume
"vol" need to be implemented using this logical manner.
3) sys/dev/sound/pcm/ac97_patch.[ch]
* Patch for AD1981B codec to enable (automuting) headphone jack sense.
4) sys/dev/sound/pcm/ac97.c
* Implement proper logical master volume for AD9181B codec
through various mix_set{parentchild,realdev}(). Tie both
"ogain" (headphone volume) and "phone" (speaker/lineout) to
a logical "vol".
5) sys/dev/sound/pcm/usb/uaudio_pcm.c
* ditto, for "vol" -> { "pcm" }.

MFC after: 1 month

Fix uninitialized variable warning.

Submitted by: dhw
Reviewed by: ryanb

MFp4 the sound Google Summer of Code project:

The goal was to sync with the OSSv4 API 4Front Technologies uses in their
proprietary OSS driver. This was successful as far as possible. The part
of the API which is stable is implemented, for the rest there are some
stubs already.

New system ioctls:
- SNDCTL_SYSINFO - obtain audio system info (version, # of audio/midi/
mixer devices, etc.)
- SNDCTL_AUDIOINFO - fetch details about a specific audio device
- SNDCTL_MIXERINFO - fetch details about a specific mixer device

New audio ioctls:
- Sync groups (SNDCTL_DSP_SYNCGROUP/SNDCTL_DSP_SYNCSTART) which allow
triggered playback/recording on multiple devices (even across processes
simultaneously).
- Peak meters (SNDCTL_DSP_GETIPEAKS/SNDCTL_DSP_GETOPEAKS) - can query
audio drivers for peak levels (needs driver support, disabled for now).
- Per channel playback/recording levels -
SNDCTL_DSP_{GET,SET}{PLAY,REC}VOL. Note that these are still in name
only, just wrapping around the AC97-style mixer at the moment. The next
step is to push them down to the drivers.

Audio ioctls still under development by 4Front (for which stubs may exist
in this commit):
- SNDCTL_GETNAME, SNDCTL_{GET,SET}{SONG,LABEL}
- SNDCTL_DSP_{GET,SET}_CHNORDER
- SNDCTL_MIX_ENUMINFO, SNDCTL_MIX_EXTINFO - (might be documented enough in
the OSS releases to work on this. These ioctls cover the cool "twiddle
any knob on your card" features.)

Missing:
- SNDCTL_DSP_COOKEDMODE -- this ioctl is used to give applications direct
access to a card's buffers, bypassing the feeder architecture. It's
a toughy -- "someone" needs to decide :
(a) if this is desireable, and (b) if it's reasonably feasible.

Updates for driver writers:
So far, only two routines to the channel class (in channel_if.m) are added.
One is for fetching a list of discrete supported playback/recording rates
of a channel, and the other is for fetching peak level info (useful for
drawing peak meters). Interested parties may want to help pushing down
SNDCTL_DSP_{GET,SET}{PLAY,REC}VOL into the drivers.

To use the new stuff you need to rebuild the sound drivers or your kernel
(depending on if you use modules or not) and to install soundcard.h (a
buildworld/installworld handles this).

Sponsored by: Google SoC 2006
Submitted by: ryanb
Many thanks to: 4Front Technologies for their cooperation, explanations
and the nice license of their soundcard.h.

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

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)

Appropriate NULL pointer checking to avoid mysterious panic during
device cloning.

Approved by: netchild (mentor)

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@

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

* Fix panic during driver unload on second attempt after failure on
first (device busy).
* Fix module unloading for sound.ko itself.

Submitted by: Ariff Abdullah <skywizard@MyBSD.org.my>
Tested by: multimedia@

Explicitly hold a reference to the cdev we have just cloned. This
closes the race where the cdev was reclaimed before it ever made it
back to devfs lookup.

Use dynamic major number allocation.

Start each of the license/copyright comments with /*-, minor shuffle of lines

Fix uninitialized variable, that breaks the build.

Approved by: hmp
Reviewed by: chris
Pointy hat to: josef (for ignoring warning)

Change the possibility to configure pcm(4) via boot/loader.conf
to use boot/device.hints now

As discussed on cvs-src@

Reviewed by: Hiten Pandya <hmp@backplane.com>

Enable pcm to read kenv variables to set default values for
mixer channels.

e.g.: pcm0.line=0

to muten input line per default.

Approved by: cg
Reviewed by: le, stefanf
Requested by: Eugene Grosbein <eugen@grosbein.pp.ru> (implicitly)
PR: kern/63771

Second half of the dev_t cleanup.

The big lines are:
NODEV -> NULL
NOUDEV -> NODEV
udev_t -> dev_t
udev2dev() -> findcdev()

Various minor adjustments including handling of userland access to kernel
space struct cdev etc.

Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.

Device megapatch 4/6:

Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.

Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.

As previously announced: discontinue use of makedev() call in soundcode.

This takes us a lot closer to refcounting dev_t.

This patch originally by cg@ with a few minor changes by me.

It is largely untested, but has been HEADSUP'ed twice, so presumably
people have not found any issues with it.

Submitted by: cg@

Fix sound LOR problems:

dsp_open: rearrange to only hold one lock at a time

dsp_close: ditto

mixer_hwvol_init: delete locking, the only consumer seems to
be the ess driver and it only call it a creation time, I
think the device will be stable across the sleepable malloc.

cmi interrupt routine: Release locks while caller chn_intr,
either this or do what emu10k1 does which is have no locks
at in the interrupt handler.

Submitted by: mat@cnd.mcgill.ca

update my email address.

Gigacommit to improve device-driver source compatibility between
branches:

Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.

This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.

Approved by: re(scottl)

Back out M_* changes, per decision of the TRB.

Approved by: trb

Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.

(hopefully) fix build breakage some people are seeing

Approved by: re

Fix some of the places where sound(4) can sleep with a lock held. (Help
courtesy of fenner).

Use semicolons at the end of function-like macros for the sake of
consistency, style and future cleanliness.

Add lock type arguments to callers of snd_mtxcreate().

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

MFS: allow multiple opens of mixer devices

many changes:

* add new channels to the end of the list so channels used in order of
addition

* de-globalise definition of struct snddev_info and provide accessor
functions where necessary.

* move the $FreeBSD$ tag in each .c file into a macro and allow the
/dev/sndstat handler to display these when set to maximum verbosity to aid
debugging.

* allow each device to register its own sndstat handler to reduce the amount
of groping sndstat must do in foreign structs.

set default 'monitor' volume (ac97 headphones) to 75%

add defines and ifdefs so this code will compile on 4.x

add spls so this code will work on 4.x

use a global devclass for all drivers - i'm not entirely sure why this
worked before.

mixer, dsp and sndstat are seperate devices - give them their own cdevsws
instead of demuxing requests sent to a single cdevsw.

use the si_drv1/si_drv2 fields in dev_t structures for holding information
specific to an open instance of mixer/dsp.

nuke /dev/{dsp,dspW,audio}[0-9]* links - this functionality is now provided
using cloning.

various locking fixes.

mega-commit.

this introduces a new buffering mechanism which results in dramatic
simplification of the channel manager.

as several structures have changed, we take the opportunity to move their
definitions into the source files where they are used, make them private and
de-typedef them.

the sound drivers are updated to use snd_setup_intr instead of
bus_setup_intr, and to comply with the de-typedefed structures.

the ac97, mixer and channel layers have been updated with finegrained
locking, as have some drivers- not all though. the rest will follow soon.

MFS: 4.x/5.x compatibility #ifdefs

- Move all of the hwvol functions into a mixer_hwvol_* namespace, and make
all of the hwvol members of struct snd_mixer live in a hwvol_* namespace.
- When changing the mixer device via the hwvol_mixer sysctl, reset the
muted state so that a mute operation on a new device won't try to
unmute the new device with the old device's saved volume.
- When the volume is muted, if a down or up volume request is received,
first restore the saved volume level and then adjust it.

Reviewed by: cg

- Make the 'hwvol_mixer' and 'hwvol_step' variables be specific to a
specific snd_mixer device rather than global across all mixers.
- Add per-mixer mute status and saved mute_level so that the mixer_hwmute()
function can now toggle the mute state when the mute button is pressed.
- Create a dynamic sysctl tree hw.snd.pcmX when a pcm device is registered.
- Move the hw.snd.hwvol_* sysctl's to hw.snd.pcmX.hwvol_* so that they
are now properly device-specific. Eventually when the mixers become
their own devices these sysctl's will move to live under a mixerX tree.
- Change the interface of the hwvol_mixer sysctl so that it reports the
name of the current mixer device instead of the number and is settable
with the name instead of the number.
- Add a new function mixer_hwinit() used to setup the dynamic sysctl's
needed for the hwvol support that can be called by drivers that support
hwvol.

Reviewed by: cg

Add a new API for soundcards that have hardware volume control:
- The mixer_hwmute() function can be called when a soundcard receives a
mute request.
- The mixer_hwstep() function can be used to adjust the volume of one or
both channels.
- The 'hw.snd.hwvol_step' sysctl determines the amount that mixer_hwstep()
adjusts the volume by on each call.
- The 'hw.snd.hwvol_mixer' sysctl specifies the mixer device to adjust the
volume on for both functions. The values used correspond to the
SOUNDCARD_MIXER_* constants.

update code dealing with snd_dbuf objects to do so using a functional interface

modify chn_setblocksize() to pick a default soft-blocksize appropriate to the
sample rate and format in use. it will aim for a power of two size small
enough to generate block sizes of at most 20ms. it will also set the
hard-blocksize taking into account rate/format conversions in use.

update drivers to implement setblocksize correctly:
updated, tested: sb16, emu10k1, maestro, solo
updated, untested: ad1816, ess, mss, sb8, csa
not updated: ds1, es137x, fm801, neomagic, t4dwave, via82c686

i lack hardware to test: ad1816, csa, fm801, neomagic
others will be updated/tested in the next few days.

kobjify.

this gives us several benefits, including:

* easier extensibility- new optional methods can be added to
ac97/mixer/channel classes without having to fixup every driver.

* forward compatibility for drivers, provided no new mandatory methods are
added.

add reinit functions to mixers
unstaticize chn_start()
add reset/resetdone functions to channels

Fix warnings by moving static functions before they are used.

add a missing return statement, doh.

change mixer api slightly
change channel interface - kobj implementation coming soonish
make pcm_makelinks not panic if modular
add pcm_unregister()

these changes support newpcm kld unloading, but this is only implemented
by ds1.c

Finally merge newmidi.
(I had been busy for my own research activity until the last weekend)

Supported devices:

SB Midi Port (sbc + midi)
SB OPL3 (sbc + midi)
16550 UART (midi, needs a trick in your hint)
CS461x Midi Port (csa + midi)

OSS-compatible sequencer (seq)

Supported playing software:

playmidi (We definitely need more)

Notes:

/dev/midistat now reports installed midi drivers. /dev/sndstat reports
only pcm drivers. We need the new name(pcmstat?).

EMU8000(SB AWE) does not sound yet but does get probed so that the OPL3
synth on an AWE card works.

TODO:

MSS/PCI bridge drivers
Midi-tty interface to support general serial devices
Modules

make mixer reads return the value written instead of the value set

people seem to want this even though it breaks oss spec compliance

add a function to reinitialize the mixer, to be called by drivers on
resuming after suspend

repo-copied to make way for newmidi, this commit updates include paths

set default ogain to 50 since some sb cards produce no sound at 0

$Id$ -> $FreeBSD$

say hello to newpcm. it is not yet enabled, requiring new pnp code from dfr
to compile successfully. further details will be provided in the commit
enabling newpcm.