[AMD Official Use Only - Internal Distribution Only]
-----Original Message----- From: Mark Brown broonie@kernel.org Sent: Tuesday, May 5, 2020 5:21 PM To: Agrawal, Akshu Akshu.Agrawal@amd.com Cc: RAVULAPATI, VISHNU VARDHAN RAO Vishnuvardhanrao.Ravulapati@amd.com; Liam Girdwood lgirdwood@gmail.com; Jaroslav Kysela perex@perex.cz; Takashi Iwai tiwai@suse.com; Mukunda, Vijendar Vijendar.Mukunda@amd.com; Colin Ian King colin.king@canonical.com; Kuninori Morimoto kuninori.morimoto.gx@renesas.com; moderated list:SOUND - SOC LAYER / DYNAMIC AUDIO POWER MANAGEM... alsa-devel@alsa-project.org; open list linux-kernel@vger.kernel.org Subject: Re: [PATCH] ASoC: amd :High hw_level while simultaneous capture
On Tue, May 05, 2020 at 05:10:20PM +0530, Akshu Agrawal wrote:
Simultaneous capture on dmic and headset mic is having issue with high hw_level being reported.
Issue Can be reproduced by: arecord -D hw:2,0 -f dat -d 60 /tmp/test0 & arecord -D hw:2,2 -f dat -d 60 /tmp/test1 & cat /proc/asound/card2/pcm?c/sub0/status
What is a "high hw_level" and how does this patch address it? As far as I can see this patch reorders some of the initialzation but it's not entirely obvious what the issue was or how this fixes it.
Actual issue is : When we open one capture stream on one instance lets say I2S_SP and then once again if we open other capture on other instance lets say I2S_BT while first capture is in progress and when we try to read the status of both running instances by below command cat /proc/asound/card2/pcm?c/sub0/status we observe that avail_max is being doubled on first opened capture(I2S_SP in the example).
This is because our previous implementation was like when any instance is opened it gets initialized in dma_open irrespective of on what instance it called open. For example: First I2S_SP called opened it initializes both SP/BT capture streams irrespective of on which instance the stream opened.next time I2S_BT called opened and it initializes both SP/BT this corrupts the behaviour .
So with this patch the stream gets initialized only on specific instance when ever it gets opened calls hw_params.
This rectifies the issue.
Thanks, Vishnu