linux.git/include/sound/seq_kernel.h, branch v6.18.21

ALSA: seq: Remove unused declarations

2024-08-17T14:32:31+00:00

These functions are never implemented and used.

Signed-off-by: Yue Haibing 
Link: https://patch.msgid.link/20240817093334.1120002-1-yuehaibing@huawei.com
Signed-off-by: Takashi Iwai

ALSA: seq: Add UMP support

2023-05-23T10:11:21+00:00

Starting from this commit, we add the basic support of UMP (Universal
MIDI Packet) events on ALSA sequencer infrastructure.  The biggest
change here is that, for transferring UMP packets that are up to 128
bits, we extend the data payload of ALSA sequencer event record when
the client is declared to support for the new UMP events.

A new event flag bit, SNDRV_SEQ_EVENT_UMP, is defined and it shall be
set for the UMP packet events that have the larger payload of 128
bits, defined as struct snd_seq_ump_event.

For controlling the UMP feature enablement in kernel, a new Kconfig,
CONFIG_SND_SEQ_UMP is introduced.  The extended event for UMP is
available only when this Kconfig item is set.  Similarly, the size of
the internal snd_seq_event_cell also increases (in 4 bytes) when the
Kconfig item is set.  (But the size increase is effective only for
32bit architectures; 64bit archs already have padding there.)
Overall, when CONFIG_SND_SEQ_UMP isn't set, there is no change in the
event and cell, keeping the old sizes.

For applications that want to access the UMP packets, first of all, a
sequencer client has to declare the user-protocol to match with the
latest one via the new SNDRV_SEQ_IOCTL_USER_PVERSION; otherwise it's
treated as if a legacy client without UMP support.

Then the client can switch to the new UMP mode (MIDI 1.0 or MIDI 2.0)
with a new field, midi_version, in snd_seq_client_info.  When switched
to UMP mode (midi_version = 1 or 2), the client can write the UMP
events with SNDRV_SEQ_EVENT_UMP flag.  For reads, the alignment size
is changed from snd_seq_event (28 bytes) to snd_seq_ump_event (32
bytes).  When a UMP sequencer event is delivered to a legacy sequencer
client, it's ignored or handled as an error.

Conceptually, ALSA sequencer client and port correspond to the UMP
Endpoint and Group, respectively; each client may have multiple ports
and each port has the fixed number (16) of channels, total up to 256
channels.

As of this commit, ALSA sequencer core just sends and receives the UMP
events as-is from/to clients.  The automatic conversions between the
legacy events and the new UMP events will be implemented in a later
patch.

Along with this commit, bump the sequencer protocol version to 1.0.3.

Reviewed-by: Jaroslav Kysela 
Link: https://lore.kernel.org/r/20230523075358.9672-26-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: Add snd_seq_expand_var_event_at() helper

2023-05-23T10:11:14+00:00

Create a new variant of snd_seq_expand_var_event() for expanding the
data starting from the given byte offset.  It'll be used by the new
UMP sequencer code later.

Reviewed-by: Jaroslav Kysela 
Link: https://lore.kernel.org/r/20230523075358.9672-19-tiwai@suse.de
Signed-off-by: Takashi Iwai

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ALSA: seq: Simplify snd_seq_kernel_client_enqueue() helper

2019-04-12T10:51:22+00:00

We have two helpers for queuing a sequencer event from the kernel
client, and both are used only from OSS sequencer layer without any
hop and atomic set.  Let's simplify and unify two helpers into one.

No functional change, just a call pattern change.

Signed-off-by: Takashi Iwai

ALSA: seq: Avoid invalid lockdep class warning

2017-11-06T19:25:31+00:00

The recent fix for adding rwsem nesting annotation was using the given
"hop" argument as the lock subclass key.  Although the idea itself
works, it may trigger a kernel warning like:
  BUG: looking up invalid subclass: 8
  ....
since the lockdep has a smaller number of subclasses (8) than we
currently allow for the hops there (10).

The current definition is merely a sanity check for avoiding the too
deep delivery paths, and the 8 hops are already enough.  So, as a
quick fix, just follow the max hops as same as the max lockdep
subclasses.

Fixes: 1f20f9ff57ca ("ALSA: seq: Fix nested rwsem annotation for lockdep splat")
Reported-by: syzbot 
Cc: 
Signed-off-by: Takashi Iwai

ALSA: seq: Drop snd_seq_autoload_lock() and _unlock()

2015-02-12T13:42:31+00:00

The autoload lock became already superfluous due to the recent rework
of autoload code.  Let's drop them now.  This allows us to simplify a
few codes nicely.

Signed-off-by: Takashi Iwai

ALSA: seq: increase the maximum number of queues

2015-01-26T12:57:29+00:00

Queues are used both for scheduling playback events and for assigning
timestamps to recorded events, so it is easy to need quite a lot of
them, especially on a multi-user system.  Additionally, the actual
queue objects are allocated dynamically, so it does not really make
sense to have a low limit.  Increase it to something still sane.

Signed-off-by: Clemens Ladisch 
Signed-off-by: Takashi Iwai

ALSA: seq: remove unused callback_all field

2015-01-26T12:56:58+00:00

Signed-off-by: Clemens Ladisch 
Signed-off-by: Takashi Iwai

ALSA: seq: remove unused symbols

2015-01-26T12:54:55+00:00

Signed-off-by: Clemens Ladisch 
Signed-off-by: Takashi Iwai