[alsa-devel] [PATCH V2] ASoC: soc-pcm: BE dai needs prepare when pause release after resume

[Yang, Libin]

Hi Mark,

>-----Original Message-----
>From: Mark Brown [mailto:broonie at kernel.org]
>Sent: Sunday, May 12, 2019 4:08 PM
>To: Yang, Libin <libin.yang at intel.com>
>Cc: Takashi Iwai <tiwai at suse.de>; Ranjani Sridharan
><ranjani.sridharan at linux.intel.com>; alsa-devel at alsa-project.org; Sridharan,
>Ranjani <ranjani.sridharan at intel.com>; pierre-louis.bossart at linux.intel.com;
>Wang, Rander <rander.wang at intel.com>
>Subject: Re: [alsa-devel] [PATCH V2] ASoC: soc-pcm: BE dai needs prepare
>when pause release after resume
>
>On Thu, May 09, 2019 at 02:30:39AM +0000, Yang, Libin wrote:
>
>> I think this may be a ASoC FE-BE defect.
>> In this case, ASoC will call FE dai prepare(), but it will not call BE
>> dai prepare() because of the judgement. This is why I made the patch.
>
>If it's calling only the front end but not the back end that definitely sounds like
>DPCM is causing trouble again.

Yes. This is caused by dpcm_be_dai_prepare(). dpcm_be_dai_prepare()
should call BE dai prepare() in the case of pause release after S3.
But as the be->dpcm[stream].state is SND_SOC_DPCM_STATE_PAUSED,
it will not call BE dai prepare.

Regards,
Libin