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| author | Takashi Iwai <tiwai@suse.de> | 2023-08-24 09:51:07 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2023-08-24 10:03:17 +0200 |
| commit | b2bcbd031d34d1ba1f491b9152474cf9f6d4d51b (patch) | |
| tree | f0bc905e40200f14cad8bd2264a0d6d86038b32e /include/sound | |
| parent | 1761f4cc114af531020ea190df6a24dd288a8221 (diff) | |
| download | linux-stable-b2bcbd031d34d1ba1f491b9152474cf9f6d4d51b.tar.gz linux-stable-b2bcbd031d34d1ba1f491b9152474cf9f6d4d51b.tar.bz2 linux-stable-b2bcbd031d34d1ba1f491b9152474cf9f6d4d51b.zip | |
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>
Diffstat (limited to 'include/sound')
| -rw-r--r-- | include/sound/ump.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/sound/ump.h b/include/sound/ump.h index 44d2c2fd021d..91238dabe307 100644 --- a/include/sound/ump.h +++ b/include/sound/ump.h @@ -45,6 +45,7 @@ struct snd_ump_endpoint { spinlock_t legacy_locks[2]; struct snd_rawmidi *legacy_rmidi; struct snd_rawmidi_substream *legacy_substreams[2][SNDRV_UMP_MAX_GROUPS]; + unsigned char legacy_mapping[SNDRV_UMP_MAX_GROUPS]; /* for legacy output; need to open the actual substream unlike input */ int legacy_out_opens; |