From 6479f7588651cbc9c91e61c20ff39119cbc8feba Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Tue, 17 Aug 2021 11:40:54 -0500 Subject: 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 Message-Id: <20210817164054.250028-3-pierre-louis.bossart@linux.intel.com> Signed-off-by: Mark Brown --- include/sound/soc-dpcm.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/sound') 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) \ -- cgit v1.2.3