Re: [PATCH] ASoC: rt5659: Add mclk controls

From: Nicolin Chen <nicoleotsuka@gmail.com>
To: Mark Brown <broonie@kernel.org>
Cc: lgirdwood@gmail.com, robh+dt@kernel.org, mark.rutland@arm.com,
	bardliao@realtek.com, oder_chiou@realtek.com,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	alsa-devel@alsa-project.org, vinod.koul@intel.com
Subject: Re: [PATCH] ASoC: rt5659: Add mclk controls
Date: Thu, 28 Jul 2016 11:14:20 -0700	[thread overview]
Message-ID: <20160728181419.GA4742@Asurada-Nvidia> (raw)
In-Reply-To: <20160728155732.GG11806@sirena.org.uk>

On Thu, Jul 28, 2016 at 04:57:32PM +0100, Mark Brown wrote:
> > The codec driver should control the mclk. So this patch adds this support.
> 
> > +	/* Check if MCLK provided */
> > +	rt5659->mclk = devm_clk_get(&i2c->dev, "mclk");
> > +	if (IS_ERR(rt5659->mclk)) {
> > +		if (PTR_ERR(rt5659->mclk) == -EPROBE_DEFER)
> > +			return -EPROBE_DEFER;
> > +		/* Otherwise mark the mclk pointer to NULL */
> > +		rt5659->mclk = NULL;
> > +	}
> 
> This device seems to be used on x86 systems so we'll need to ensure that
> they register clocks for this.  They really should set this up using
> quirks keyed off DMI information or similar so it's hidden from other
> systems.

Hmm..the change defines this mclk as a optional property so I'm
not sure how it would affect x86 systems. (Would love to refine
it to make it impactless.) Since it's literally hidden, any way
that I can manually ensure it? Or just wait for an ack from x86
developers?

Thanks
Nicolin