linux-kernel - Re: [PATCH 3/6] ASoC: ux500: Drop pinctrl sleep support

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Date:	Wed, 8 May 2013 14:54:13 +0100
From:	Mark Brown <broonie@...nel.org>
To:	Fabio Baltieri <fabio.baltieri@...aro.org>
Cc:	Liam Girdwood <lgirdwood@...il.com>, alsa-devel@...a-project.org,
	linux-kernel@...r.kernel.org,
	Linus Walleij <linus.walleij@...aro.org>,
	Lee Jones <lee.jones@...aro.org>,
	Ola Lilja <ola.o.lilja@...ricsson.com>
Subject: Re: [PATCH 3/6] ASoC: ux500: Drop pinctrl sleep support

On Wed, May 08, 2013 at 03:10:20PM +0200, Fabio Baltieri wrote:
> On Wed, May 08, 2013 at 01:32:25PM +0100, Mark Brown wrote:

> > I'm saying that if functions like enable_msp() don't work reliably then
> > removing some but not all of their functionality isn't an obviously good
> > approach to fixing that.  Why does the other functionality work well but
> > not this bit?  It sounds like there's some reference counting bug here
> > is all...

> Yes, it started as a reference counting bug, due to the actual counter
> not being shared between ux500-msp-i2s instances.

> That said, the actual fork of this driver deployed by STE internally
> does not handle I2S pin sleep state, and I was not able to find any
> other ASoC driver that does that, which seems reasonable to me as I
> can't come up with a reason to put those pins in hi-z anyway.

But why does the rest of the code work well if the reference counting is
wrong, it's in the middle of a big block of code?  This all smells like
this change is papering over a specific symptom of some underlying issue
- if that's not the case then it needs to be clearer why.

> If I understood the problem correctly you do that when you want to cut
> power completely to some peripherals to avoid spurious current paths,
> and that should not be the case for the audio codec, especially in this
> case where it's part of a big multifuntion IC.

Being a MFD should have nothing to do with this?

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