Re: [PATCH 5.3 112/112] ASoC: sgtl5000: add ADC mute control

[Richard Leitner]

On 17/10/2019 01:23, Greg Kroah-Hartman wrote:
> On Wed, Oct 16, 2019 at 11:35:18PM +0100, Mark Brown wrote:
> > On Wed, Oct 16, 2019 at 03:10:25PM -0700, Greg Kroah-Hartman wrote:
> > > On Wed, Oct 16, 2019 at 11:00:44PM +0100, Mark Brown wrote:
> > > > On Wed, Oct 16, 2019 at 02:51:44PM -0700, Greg Kroah-Hartman wrote:
> > > > > From: Oleksandr Suvorov <oleksandr.suvorov@xxxxxxxxxxx>
> >
> > > > > commit 694b14554d75f2a1ae111202e71860d58b434a21 upstream.
> >
> > > > > This control mute/unmute the ADC input of SGTL5000
> > > > > using its CHIP_ANA_CTRL register.
> >
> > > > This seems like a new feature and not an obvious candidate for stable?
> >
> > > there was a long email from Richard that said:
> > > 	Upstream commit 631bc8f0134a ("ASoC: sgtl5000: Fix of unmute
> > > 	outputs on probe"), which is e9f621efaebd in v5.3 replaced
> > > 	snd_soc_component_write with snd_soc_component_update_bits and
> > > 	therefore no longer cleared the MUTE_ADC flag. This caused the
> > > 	ADC to stay muted and recording doesn't work any longer. This
> > > 	patch fixes this problem by adding a Switch control for
> > > 	MUTE_ADC.
> >
> > > That's why I took this.  If this isn't true, I'll be glad to drop this.
> >
> > That's probably not an appropriate fix for stable - it's going to add a
> > new control which users will need to manually set (or hope their
> > userspace automatically figures out that it should set for them, more
> > advanced userspaces like PulseAudio should) which isn't a drop in fix.
> > You could either drop the backport that was done for zero cross or take
> > a new patch that clears the MUTE_ADC flag (rather than punting to
> > userspace to do so), or just be OK with what you've got at the minute
> > which might be fine given the lack of user reports.
>
> Ok, I'll gladly go drop it, thanks!

Mark, thanks for the clarification! I haven't thought of breaking 
anything with the backport as it worked fine for our application.

Greg, just to be sure:

Are you going to drop this patch and revert e9f621efaebd for v5.3?

Or should I send a patch which clears the MUTE_ADC flag like Mark
suggested?

thanks & regards;Richard.L