diff options
| author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2021-12-07 11:37:44 -0600 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2021-12-14 17:15:47 +0000 |
| commit | 848aedfdc6ba25ad5652797db9266007773e44dd (patch) | |
| tree | 02991346d21fdff6077751739e75d1ec3b5382d4 /include/sound | |
| parent | b2ae80663008a7662febe7d13f14ea1b2eb0cd51 (diff) | |
ASoC: soc-pcm: test refcount before triggering
On start/pause_release/resume, when more than one FE is connected to
the same BE, it's possible that the trigger is sent more than
once. This is not desirable, we only want to trigger a BE once, which
is straightforward to implement with a refcount.
For stop/pause/suspend, the problem is more complicated: the check
implemented in snd_soc_dpcm_can_be_free_stop() may fail due to a
conceptual deadlock when we trigger the BE before the FE. In this
case, the FE states have not yet changed, so there are corner cases
where the TRIGGER_STOP is never sent - the dual case of start where
multiple triggers might be sent.
This patch suggests an unconditional trigger in all cases, without
checking the FE states, using a refcount protected by the BE PCM
stream lock.
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/20211207173745.15850-6-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'include/sound')
| -rw-r--r-- | include/sound/soc-dpcm.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/sound/soc-dpcm.h b/include/sound/soc-dpcm.h index bc7af90099a8..75b92d883976 100644 --- a/include/sound/soc-dpcm.h +++ b/include/sound/soc-dpcm.h @@ -101,6 +101,8 @@ struct snd_soc_dpcm_runtime { enum snd_soc_dpcm_state state; int trigger_pending; /* trigger cmd + 1 if pending, 0 if not */ + + int be_start; /* refcount protected by BE stream pcm lock */ }; #define for_each_dpcm_fe(be, stream, _dpcm) \ |