linux.git/sound/core/seq/seq_ports.c, branch for-next

ALSA: seq: Fix missing seq port info bit return for MIDI 1.0 block

2024-08-07T09:31:38+00:00

The recent extension added a new ALSA sequencer port info flag bit
SNDRV_SEQ_PORT_FLG_IS_MIDI1, but it's not reported back when
inquired.  Fix it to report properly.

Fixes: 0079c9d1e58a ("ALSA: ump: Handle MIDI 1.0 Function Block in MIDI 2.0 protocol")
Signed-off-by: Takashi Iwai 
Link: https://patch.msgid.link/20240807092303.1935-7-tiwai@suse.de

ALSA: ump: Handle MIDI 1.0 Function Block in MIDI 2.0 protocol

2024-08-06T07:01:23+00:00

The UMP v1.1 spec says in the section 6.2.1:
"If a UMP Endpoint declares MIDI 2.0 Protocol but a Function Block
represents a MIDI 1.0 connection, then may optionally be used for
messages to/from that Function Block."

It implies that the driver can (and should) keep MIDI 1.0 CVM
exceptionally for those FBs even if UMP Endpoint is running in MIDI
2.0 protocol, and the current driver lacks of it.

This patch extends the sequencer port info to indicate a MIDI 1.0
port, and tries to send/receive MIDI 1.0 CVM as is when this port is
the source or sink.  The sequencer port flag is set by the driver at
parsing FBs and GTBs although application can set it to its own
user-space clients, too.

Link: https://patch.msgid.link/20240806070024.14301-1-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: ports: Use guard() for locking

2024-02-28T14:01:21+00:00

We can simplify the code gracefully with new guard() macro and co for
automatic cleanup of locks.

Only the code refactoring, and no functional changes.

Signed-off-by: Takashi Iwai 
Link: https://lore.kernel.org/r/20240227085306.9764-15-tiwai@suse.de

ALSA: seq: Fix memory leak at error path in snd_seq_create_port()

2023-07-17T06:26:15+00:00

We forgot to release a newly allocated item at the error path in
snd_seq_create_port().  This patch fixes it.

Fixes: 7c3f0d3d3a11 ("ALSA: seq: Check the conflicting port at port creation")
Reported-by: syzbot+cf8e7fa4eeec59b3d485@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/00000000000098ed3a0600965f89@google.com
Link: https://lore.kernel.org/r/20230717062555.31592-1-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: Add UMP group number to snd_seq_port_info

2023-05-23T10:11:27+00:00

Add yet more new filed "ump_group" to snd_seq_port_info for specifying
the associated UMP Group number for each sequencer port.  This will be
referred in the upcoming automatic UMP conversion in sequencer core.

Reviewed-by: Jaroslav Kysela 
Link: https://lore.kernel.org/r/20230523075358.9672-30-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: Add port direction to snd_seq_port_info

2023-05-23T10:11:25+00:00

Add a new field "direction" to snd_seq_port_info for allowing a client
to tell the expected direction of the port access.  A port might still
allow subscriptions for read/write (e.g. for MIDI-CI) even if the
primary usage of the port is a single direction (either input or
output only).  This new "direction" field can help to indicate such
cases.

When the direction is unspecified at creating a port and the port has
either read or write capability, the corresponding direction bits are
set automatically as default.

Reviewed-by: Jaroslav Kysela 
Link: https://lore.kernel.org/r/20230523075358.9672-29-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: Add port inactive flag

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

This extends the ALSA sequencer port capability bit to indicate the
"inactive" flag.  When this flag is set, the port is essentially
invisible, and doesn't appear in the port query ioctls, while the
direct access and the connection to this port are still allowed.  The
active/inactive state can be flipped dynamically, so that it can be
visible at any time later.

This feature is introduced basically for UMP; some UMP Groups in a UMP
Block may be unassigned, hence those are practically invisible.  On
ALSA sequencer, the corresponding sequencer ports will get this new
"inactive" flag to indicate the invisible state.

Reviewed-by: Jaroslav Kysela 
Link: https://lore.kernel.org/r/20230523075358.9672-27-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: Check the conflicting port at port creation

2023-05-23T10:11:17+00:00

We didn't check if a port with the given port number has been already
present at creating a new port.  Check it and return -EBUSY properly
if the port number conflicts.

Reviewed-by: Jaroslav Kysela 
Link: https://lore.kernel.org/r/20230523075358.9672-22-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: replace ternary operator with max()

2022-05-17T06:49:42+00:00

Fix the following coccicheck warning:

sound/core/seq/seq_ports.c:142:12-14: WARNING opportunity for max()

Signed-off-by: Guo Zhengkui 
Link: https://lore.kernel.org/r/20220517062518.123292-1-guozhengkui@vivo.com
Signed-off-by: Takashi Iwai

ALSA: seq: Fix racy deletion of subscriber

2021-08-03T11:43:40+00:00

It turned out that the current implementation of the port subscription
is racy.  The subscription contains two linked lists, and we have to
add to or delete from both lists.  Since both connection and
disconnection procedures perform the same order for those two lists
(i.e. src list, then dest list), when a deletion happens during a
connection procedure, the src list may be deleted before the dest list
addition completes, and this may lead to a use-after-free or an Oops,
even though the access to both lists are protected via mutex.

The simple workaround for this race is to change the access order for
the disconnection, namely, dest list, then src list.  This assures
that the connection has been established when disconnecting, and also
the concurrent deletion can be avoided.

Reported-and-tested-by: folkert 
Cc: 
Link: https://lore.kernel.org/r/20210801182754.GP890690@belle.intranet.vanheusden.com
Link: https://lore.kernel.org/r/20210803114312.2536-1-tiwai@suse.de
Signed-off-by: Takashi Iwai