MFC r359446:
Add support for multiple playback and recording devices per physical USB audio
device. This requires some structural refactoring inside the driver, mostly
about converting existing audio channel structures into arrays.

The main audio mixer is provided by the first PCM instance.
The non-first audio instances may only have a software mixer for PCM playback.

Tested by: Horse Ma <Shichun.Ma@dell.com>
Sponsored by: Mellanox Technologies

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

The synchronisation value returned by the so-called feedback endpoint
appears to be too inaccurate that it can be used to synchronize the
playback data stream. If there is a recording endpoint associated with
the playback endpoint, use that instead. That means if the isochronous
OUT endpoint is asynchronus the USB audio driver will automatically
start recording, if possible, to get exact information about the
needed sample rate adjustments. In no recording endpoint is present,
no rate adaption will be done.

While at it fix an issue where the hardware buffer pointers don't get
reset at the first device PCM trigger.

Make some variables 32-bit to avoid problems with multithreading.

MFC after: 3 days
PR: 198444

Stop USB audio transfers early so that any audio applications
will time out and close opened /dev/dspX.Y device(s), if
any. This is a workaround because we cannot unregister PCM
devices while the audio character device is in use.

Add a missing inclusion guard.

MFC after: 1 weeks

Purge mergeinfo from files that were temporarily renamed while USB2 was
imported into the tree alongside USB.

Approved by: re (mergeinfo blanket)

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.

Remove pointeless mergeinfo that crept in from r190633.

Implement an ipfw action to reassemble ip packets: reass.

Integrate user/mav/ata branch:

Add ch_suspend/ch_resume methods for PCI controllers and implement them
for AHCI. Refactor AHCI channel initialization according to it.

Fix Port Multipliers operation. It is far from perfect yet, but works now.
Tested with JMicron JMB363 AHCI + SiI 3726 PMP pair.
Previous version was also tested with SiI 4726 PMP.

Hardware sponsored by: Vitsch Electronics / VEHosting.nl

Merge in support for Xen HVM on amd64 architecture.

Move the uaudio and ata-usb drivers into their correct locations.

Move the new USB stack into its new home.

Format and wrap function declarations.

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