kernel/linux.git/sound/core/seq/seq_clientmgr.h, branch v7.0.10

ALSA: seq: Fix UMP group 16 filtering

2026-05-14T13:31:05+00:00

commit 92429ca999db99febced82f23362a71b2ba4c1d8 upstream. The sequencer UAPI defines group_filter as an unsigned int bitmap. Bit 0 filters groupless messages and bits 1-16 filter UMP groups 1-16. The internal snd_seq_client storage is only unsigned short, so bit 16 is truncated when userspace sets the filter. The same truncation affects the automatic UMP client filter used to avoid delivery to inactive groups, so events for group 16 cannot be filtered. Store the internal bitmap as unsigned int and keep both userspace-provided and automatically generated values limited to the defined UAPI bits. Fixes: d2b706077792 ("ALSA: seq: Add UMP group filter") Cc: stable@vger.kernel.org Signed-off-by: Cássio Gabriel Link: https://patch.msgid.link/20260506-alsa-seq-ump-group16-filter-v1-1-b75160bf6993@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: seq: Use auto-cleanup for client refcounting

2025-08-29T09:52:35+00:00

The current code manages the refcount of client in a way like: snd_seq_client *client; client = clientptr(id); .... snd_seq_client_unlock(client); Now we introduce an auto-cleanup macro to manage the unlock implicitly, namely, the above will be replaced like: snd_seq_client *client __free(snd_seq_client) = NULL; client = clientptr(id); and we can forget the unref call. A part of the code in snd_seq_deliver_single_event() is factored out to a function, so that the auto-cleanups can be applied cleanly. This also allows us to replace some left mutex lock/unlock with guard(), and also reduce scoped_guard() to the normal guard(), too. Only code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250827080520.7544-5-tiwai@suse.de

ALSA: seq: Clean up spin lock with guard()

2025-08-29T09:52:35+00:00

Use guard() for spin locks to manage the sequencer client locking. The code about the refcounting was modified with the new snd_seq_client_ref() and *_unref() helpers instead of the ugly goto, too. Only code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250827080520.7544-3-tiwai@suse.de

ALSA: seq: Simplify internal command operation from OSS layer

2025-08-29T09:52:35+00:00

snd_seq_client_ioctl_lock() and *_unlock() are used only from a single function of the OSS layer, and it's just to wrap the call of snd_seq_kernel_client_ctl(). Provide another variant of snd_seq_kernel_client_ctl() that takes the locks internally and drop the ugly snd_seq_client_ioctl_lock() and *_unlock() implementations, instead. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250827080520.7544-2-tiwai@suse.de

ALSA: seq: Add UMP group filter

2023-05-23T10:11:38+00:00

Add a new filter bitmap for UMP groups for reducing the unnecessary read/write when the client is connected to UMP EP seq port. The new group_filter field contains the bitmap for the groups, i.e. when the bit is set, the corresponding group is filtered out and the messages to that group won't be delivered. The filter bitmap consists of each bit of 1-based UMP Group number. The bit 0 is reserved for the future use. Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230523075358.9672-37-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: seq: Add ioctls for client UMP info query and setup

2023-05-23T10:11:36+00:00

Add new ioctls for sequencer clients to query and set the UMP endpoint and block information. As a sequencer client corresponds to a UMP Endpoint, one UMP Endpoint information can be assigned at most to a single sequencer client while multiple UMP block infos can be assigned by passing the type with the offset of block id (i.e. type = block_id + 1). For the kernel client, only SNDRV_SEQ_IOCTL_GET_CLIENT_UMP_INFO is allowed. Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230523075358.9672-35-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: seq: Automatic conversion of UMP events

2023-05-23T10:11:28+00:00

This patch enables the automatic conversion of UMP events from/to the legacy ALSA sequencer MIDI events. Also, as UMP itself has two different modes (MIDI 1.0 and MIDI 2.0), yet another converters between them are needed, too. Namely, we have conversions between the legacy and UMP like: - seq legacy event -> seq UMP MIDI 1.0 event - seq legacy event -> seq UMP MIDI 2.0 event - seq UMP MIDI 1.0 event -> seq legacy event - seq UMP MIDI 2.0 event -> seq legacy event and the conversions between UMP MIDI 1.0 and 2.0 clients like: - seq UMP MIDI 1.0 event -> seq UMP MIDI 2.0 event - seq UMP MIDI 2.0 event -> seq UMP MIDI 1.0 event The translation is per best-effort; some MIDI 2.0 specific events are ignored when translated to MIDI 1.0. Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230523075358.9672-31-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: seq: Support MIDI 2.0 UMP Endpoint port

2023-05-23T10:11:24+00:00

This is an extension to ALSA sequencer infrastructure to support the MIDI 2.0 UMP Endpoint port. It's a "catch-all" port that is supposed to be present for each UMP Endpoint. When this port is read via subscription, it sends any events from all ports (UMP Groups) found in the same client. A UMP Endpoint port can be created with the new capability bit SNDRV_SEQ_PORT_CAP_UMP_ENDPOINT. Although the port assignment isn't strictly defined, it should be the port number 0. Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230523075358.9672-28-tiwai@suse.de 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: Introduce SNDRV_SEQ_IOCTL_USER_PVERSION ioctl

2023-05-23T10:11:19+00:00

For the future extension of ALSA sequencer ABI, introduce a new ioctl SNDRV_SEQ_IOCTL_USER_PVERSION. This is similar like the ioctls used in PCM and other interfaces, for an application to specify its supporting ABI version. The use of this ioctl will be mandatory for the upcoming UMP support. Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20230523075358.9672-25-tiwai@suse.de Signed-off-by: Takashi Iwai