Hi Liam, We have a problem encountered in ALSA framework wrt FE/BE disconnection and fix to it is mentioned in below code change. please check it and provide your valuable comments.

---------------------- From: Laxminath Kasam lkasam@codeaurora.org Date: Wed, 3 Apr 2013 14:03:17 +0530 Subject: [PATCH] ASoC: audio: Fix BE not disconnected even codec teardown

Scenario: When FE1(LowLatency) comes in which opens BE1 and puts it in state SND_SOC_DPCM_STATE_START. Similarly FE2(LPA) comes in with connecting to same BE. Now FE2 is in SND_SOC_DPCM_STATE_PREPARE state and waits for TRIGGER_START. Meanwhile FE1 is closed which doesn't affect BE1 and FE2 which are connected. Also, for FE2 pcm_close is called before TRIGGER_START itself. In such a case, BE1 is not getting disconnected while Codec is teared down resulting in failures.

Fix: Whenever BE1 is found to be in SND_SOC_DPCM_STATE_START state and FE1 being connected is not started yet, and close sequence happens for this FE, then allow hw_free to happen for BE1 if this is the only FE connected to this BE1. This allows BE to be disconnected which calls afe_close then followed by Codec teardown not resulting in any failures.

Signed-off-by: Laxminath Kasam lkasam@codeaurora.org --- sound/soc/soc-pcm.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 915c3c2..ed0ea86 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -1765,7 +1765,12 @@ static int soc_dpcm_be_dai_hw_free(struct snd_soc_pcm_runtime *fe, int stream) (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PREPARE) && (be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_FREE) && (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED) && - (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP)) + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) && + !((be->dpcm[stream].state == SND_SOC_DPCM_STATE_START)&& + ((fe->dpcm[stream].state != SND_SOC_DPCM_STATE_START) && + (fe->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED) && + (fe->dpcm[stream].state != + SND_SOC_DPCM_STATE_SUSPEND)))) continue;

dev_dbg(be->dev, "dpcm: hw_free BE %s\n", -- -----------------------------------------

Please let me know if you are looking for more details.

Thanks Kasam