linux-kernel - Re: [PATCH v1 3/4] ASoC: Intel: bytcr_rt5651: use devm_clk_get

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Date:   Wed, 6 Oct 2021 19:23:02 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
Cc:     Mark Brown <broonie@...nel.org>, alsa-devel@...a-project.org,
        linux-kernel@...r.kernel.org,
        Cezary Rojewski <cezary.rojewski@...el.com>,
        Liam Girdwood <liam.r.girdwood@...ux.intel.com>,
        Jie Yang <yang.jie@...ux.intel.com>,
        Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>
Subject: Re: [PATCH v1 3/4] ASoC: Intel: bytcr_rt5651: use
 devm_clk_get_optional() for mclk

On Wed, Oct 06, 2021 at 10:51:52AM -0500, Pierre-Louis Bossart wrote:
> On 10/6/21 10:04 AM, Andy Shevchenko wrote:
> > The devm_clk_get_optional() helper returns NULL when devm_clk_get()
> > returns -ENOENT. This makes things slightly cleaner. The added benefit
> > is mostly cosmetic.

...

> >  	if (SND_SOC_DAPM_EVENT_ON(event)) {
> > -		if (byt_rt5651_quirk & BYT_RT5651_MCLK_EN) {
> > -			ret = clk_prepare_enable(priv->mclk);
> > -			if (ret < 0) {
> > -				dev_err(card->dev,
> > -					"could not configure MCLK state");
> > -				return ret;
> > -			}
> > +		ret = clk_prepare_enable(priv->mclk);
> > +		if (ret < 0) {
> > +			dev_err(card->dev, "could not configure MCLK state");
> > +			return ret;
> >  		}
> 
> I don't get why you removed the test on the BYT_RT5651_MCLK_EN quirk,
> see below it was designed as a fall-back mode. We don't want to return
> an error when we know the clock is not present/desired.

Why should we do a unneeded test? When we switch to the optional, there
will be no error from these CCF APIs. Besides that it drops indentation
level and makes code neat.

...

> same here, why was the quirk removed?

Same answer.

...

> that part in the probe looks fine, but the changes above are controversial.

I didn't get. How controversial? Why? The whole point of _optional is to get
rid of unneeded checks (since they are _anyway_ be called).

-- 
With Best Regards,
Andy Shevchenko