linux-kernel - Re: [alsa-devel] [PATCH 04/15] ASoC: wm5100: Update locking around use of DAPM pin API

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Message-ID: <20140218092429.GB18502@opensource.wolfsonmicro.com>
Date:	Tue, 18 Feb 2014 09:24:29 +0000
From:	Charles Keepax <ckeepax@...nsource.wolfsonmicro.com>
To:	Mark Brown <broonie@...nel.org>
Cc:	alsa-devel@...a-project.org, lars@...afoo.de,
	eric.y.miao@...il.com, dmitry.torokhov@...il.com,
	lgirdwood@...il.com, haojian.zhuang@...il.com,
	linux-kernel@...r.kernel.org, peter.ujfalusi@...com,
	cw00.choi@...sung.com, myungjoo.ham@...sung.com,
	patches@...nsource.wolfsonmicro.com, linux@....linux.org.uk,
	jarkko.nikula@...mer.com
Subject: Re: [alsa-devel] [PATCH 04/15] ASoC: wm5100: Update locking around
	use of DAPM pin API

On Tue, Feb 18, 2014 at 09:47:29AM +0900, Mark Brown wrote:
> On Mon, Feb 17, 2014 at 04:51:32PM +0000, Charles Keepax wrote:
> 
> > +		snd_soc_dapm_force_enable_pin_locked(&codec->dapm, "CP2");
> > +		snd_soc_dapm_force_enable_pin_locked(&codec->dapm, "SYSCLK");
> > +
> > +		mutex_unlock(&codec->dapm.card->dapm_mutex);
> > +
> >  		snd_soc_dapm_sync(&codec->dapm);
> 
> With all these patches it seems weird that we have to drop the lock to
> do the sync which will immediately retake it.  It's not broken but it
> looks off - it would be better to have a version of _sync() that we can
> call within the lock.

No problem to add a version of sync that can be called from
within the lock, should help out with Dimtry's comments as well.

> 
> Regarding the naming issue that Lars mentioned I think the current
> operations are probably fine but calling them _unlocked() meaning they
> don't do any locking (as distinct from the existing _locked() which take
> locks) might be OK.

Yeah that would be good, since my original aim here was to avoid
updating every single usage of these functions.

Thanks,
Charles
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