linux-kernel - Re: [PATCH] ASoC: codec: wm8960: complete discharge on BIAS OFF->STANDBY

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Date:   Tue, 15 Feb 2022 10:55:35 +0000
From:   Charles Keepax <ckeepax@...nsource.cirrus.com>
To:     "Viorel Suman (OSS)" <viorel.suman@....nxp.com>
CC:     Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>,
        Jaroslav Kysela <perex@...ex.cz>,
        Takashi Iwai <tiwai@...e.com>,
        Shengjiu Wang <shengjiu.wang@...escale.com>,
        Daniel Baluta <daniel.baluta@....com>,
        Viorel Suman <viorel.suman@....com>,
        <patches@...nsource.cirrus.com>, <alsa-devel@...a-project.org>,
        <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] ASoC: codec: wm8960: complete discharge on BIAS
 OFF->STANDBY

On Tue, Feb 08, 2022 at 02:17:27PM +0200, Viorel Suman (OSS) wrote:
> From: Viorel Suman <viorel.suman@....com>
> 
> On BIAS STANDBY->OFF transition the current implementation sleeps
> 600ms on suspend in order to discharge the chip. The suspend is
> propagated from "snd_soc_suspend" call for all audio cards in a
> serial fashion, thus in case of boards like i.MX8DXL EVK which has
> 3 distinct WM8960 codecs the total cumulated sleep on suspend is 1.8
> seconds.
> 
> On the other hand the BIAS OFF->STANDBY transition happens
> asynchronously with regard to "snd_soc_resume" - the call is
> propagated from "soc_resume_deferred" which is just scheduled
> from "snd_soc_resume", each card having its own work scheduled to
> execute "soc_resume_deferred" call.
> 
> The patch performs discharge completion on BIAS OFF->STANDBY transition
> so that the cumulated effect on suspend described above is avoided
> and discharge is completed in paralel in case of multiple WM8960
> codecs on the board.
> 
> Signed-off-by: Viorel Suman <viorel.suman@....com>
> ---

Apologies Mark not sure how I missed this one, a bit late now,
but the change looks good to me.

Acked-by: Charles Keepax <ckeepax@...nsource.cirrus.com>

Thanks,
Charles