diff options
author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2021-08-17 19:40:54 +0300 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2021-08-26 19:42:08 +0300 |
commit | 6479f7588651cbc9c91e61c20ff39119cbc8feba (patch) | |
tree | 9b3e7724b27293e80d2f13a81fdd0f18308779e9 /include/sound | |
parent | 0c75fc7193387776c10f7c7b440d93496e3d5e21 (diff) | |
download | linux-6479f7588651cbc9c91e61c20ff39119cbc8feba.tar.xz |
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 a spinlock.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Message-Id: <20210817164054.250028-3-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 e296a3949b18..6cc751002da7 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 dpcm_lock */ }; #define for_each_dpcm_fe(be, stream, _dpcm) \ |