ALSA: ump: Don't create unused substreams for static blocks

When the UMP Endpoint is declared as "static", that is, no dynamic
reassignment of UMP Groups, it makes little sense to expose always all
16 groups with 16 substreams. Many of those substreams are disabled
groups, hence they are useless, but applications don't know it and try
to open / access all those substreams unnecessarily.

This patch limits the number of UMP legacy rawmidi substreams only to
the active groups. The behavior is changed only for the static
endpoint (i.e. devices without UMP v1.1 feature implemented or with
the static block flag is set).

Fixes: 0b5288f5fe63 ("ALSA: ump: Add legacy raw MIDI support")
Link: https://lore.kernel.org/r/20230824075108.29958-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: ump: Export snd_ump_receive_ump_val()

This is another preliminary patch for USB MIDI 2.0 gadget driver.
Export the currently local snd_ump_receive_ump_val(). It can be used
by the gadget driver for processing the UMP data.

Link: https://lore.kernel.org/r/20230621110241.4751-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: ump: Add no_process_stream flag

This is another preliminary patch for USB MIDI 2.0 gadget driver.
Add a new flag, no_process_stream, to snd_ump for suppressing the UMP
Stream message handling in UMP core.

Link: https://lore.kernel.org/r/20230621110241.4751-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: ump: Add helper to change MIDI protocol

This is a preliminary patch for MIDI 2.0 USB gadget driver.
Export a new helper to allow changing the current MIDI protocol from
the outside.

Link: https://lore.kernel.org/r/20230621110241.4751-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: seq: ump: Notify UMP protocol change to sequencer

UMP v1.1 supports the protocol switch via a UMP Stream message. When
it's received, we need to take care of the midi_version field in the
corresponding sequencer client, too.

This patch introduces a new ops to notify the protocol change to
snd_seq_ump_ops for handling it.

Link: https://lore.kernel.org/r/20230612081054.17200-9-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: seq: ump: Handle FB info update

This patch implements the handling of the dynamic update of FB info.

When the FB info update is received after the initial parsing, it
means the dynamic FB info update. We compare the result, and if the
actual update is detected, it's notified via a new ops,
notify_fb_change, to the sequencer client, and the corresponding
sequencer ports are updated accordingly.

Link: https://lore.kernel.org/r/20230612081054.17200-7-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: seq: ump: Handle groupless messages

The UMP Utility and Stream messages are "groupless", i.e. an incoming
groupless packet should be sent only to the UMP EP port, and the event
with the groupless message is sent to UMP EP as is without the group
translation per port.

Also, the former reserved bit 0 for the client group filter is now
used for groupless events. When the bit 0 is set, the groupless
events are filtered out and skipped.

Link: https://lore.kernel.org/r/20230612081054.17200-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: ump: Support UMP Endpoint and Function Block parsing

This patch adds the basic support for UMP Endpoint and UMP Function
Block parsing, which are extended in the new UMP v1.1 spec.
The patch provides a new helper function to perform the query of the
UMP Endpoint information and builds up the UMP blocks based on UMP
Function Block information. For the communication over the UMP
Endpoint, it opens the rawmidi device once internally, inquiries the
UMP Endpoint and Function Block info by sending new UMP Stream
messages, and waits for the response for each query.

The new UMP spec allows to update the FB info and change its
associated groups or its activeness on the fly, too. For catching it,
the UMP core keeps watching the incoming UMP messages, and
snd_ump_receive() handles the incoming UMP Stream messages to refresh
the FB info.

Link: https://lore.kernel.org/r/20230612081054.17200-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: seq: Bind UMP device

This patch introduces a new ALSA sequencer client for the kernel UMP
object, snd-seq-ump-client. It's a UMP version of snd-seq-midi
driver, while this driver creates a sequencer client per UMP endpoint
which contains (fixed) 16 ports.

The UMP rawmidi device is opened in APPEND mode for output, so that
multiple sequencer clients can share the same UMP endpoint, as well as
the legacy UMP rawmidi devices that are opened in APPEND mode, too.
For input, on the other hand, the incoming data is processed on the
fly in the dedicated hook, hence it doesn't open a rawmidi device.

The UMP packet group is updated upon delivery depending on the target
sequencer port (which corresponds to the actual UMP group).

Each sequencer port sets a new port type bit,
SNDRV_SEQ_PORT_TYPE_MIDI_UMP, in addition to the other standard
types for MIDI.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230523075358.9672-33-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: ump: Add legacy raw MIDI support

This patch extends the UMP core code to support the legacy MIDI 1.0
rawmidi devices. When the new kconfig CONFIG_SND_UMP_LEGACY_RAWMIDI
is set, the UMP core allows to attach an additional rawmidi device for
each UMP Endpoint. The rawmidi device contains 16 substreams where
each substream corresponds to a UMP Group belonging to the EP. The
device reads/writes the legacy MIDI 1.0 byte streams and translates
from/to UMP packets.

The legacy rawmidi devices are exclusive with the UMP rawmidi devices,
hence both of them can't be opened at the same time unless the UMP
rawmidi is opened in APPEND mode.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230523075358.9672-15-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: ump: Redirect rawmidi substream access via own helpers

This is a code refactoring for abstracting the rawmidi access to the
UMP's own helpers. It's a preliminary work for the later code
refactoring of the UMP layer.

Until now, we access to the rawmidi substream directly from the
driver via rawmidi access helpers, but after this change, the driver
is supposed to access via the newly introduced snd_ump_ops and
receive/transmit via snd_ump_receive() and snd_ump_transmit() helpers.
As of this commit, those are merely wrappers for the rawmidi
substream, and no much function change is seen here.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230523075358.9672-14-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: rawmidi: UMP support

This patch adds the support helpers for UMP (Universal MIDI Packet) in
ALSA core.

The basic design is that a rawmidi instance is assigned to each UMP
Endpoint. A UMP Endpoint provides a UMP stream, typically
bidirectional (but can be also uni-directional, too), which may hold
up to 16 UMP Groups, where each UMP (input/output) Group corresponds
to the traditional MIDI I/O Endpoint.

Additionally, the ALSA UMP abstraction provides the multiple UMP
Blocks that can be assigned to each UMP Endpoint. A UMP Block is a
metadata to hold the UMP Group clusters, and can represent the
functions assigned to each UMP Group. A typical implementation of UMP
Block is the Group Terminal Blocks of USB MIDI 2.0 specification.

For distinguishing from the legacy byte-stream MIDI device, a new
device "umpC*D*" will be created, instead of the standard (MIDI 1.0)
devices "midiC*D*". The UMP instance can be identified by the new
rawmidi info bit SNDRV_RAWMIDI_INFO_UMP, too.

A UMP rawmidi device reads/writes only in 4-bytes words alignment,
stored in CPU native endianness.

The transmit and receive functions take care of the input/out data
alignment, and may return zero or aligned size, and the params ioctl
may return -EINVAL when the given input/output buffer size isn't
aligned.

A few new UMP-specific ioctls are added for obtaining the new UMP
endpoint and block information.

As of this commit, no ALSA sequencer instance is attached to UMP
devices yet. They will be supported by later patches.

Along with those changes, the protocol version for rawmidi is bumped
to 2.0.3.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230523075358.9672-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>