ASoC: soc-pcm: serialize BE triggers

Browse source

When more than one FE is connected to a BE, e.g. in a mixing use case,
the BE can be triggered multiple times when the FE are opened/started
concurrently. This race condition is problematic in the case of
SoundWire BE dailinks, and this is not desirable in a general
case.

This patch relies on the existing BE PCM lock, which takes atomicity into
account. The locking model assumes that all interactions start with
the FE, so that there is no deadlock between FE and BE locks.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
[test, checkpatch fix and clarification of commit message by plbossart]
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20211207173745.15850-5-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

...

This commit is contained in:

Takashi Iwai 2021-12-07 11:37:43 -06:00 • committed by Mark Brown

parent b7898396f4

commit b2ae806630

No known key found for this signature in database

GPG key ID: 24D68B725D5487D0

1 changed files with 29 additions and 17 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

46

sound/soc/soc-pcm.c

View file