Re: [PATCH v3 1/2] ASoC: codecs: add TA5720 digital amplifier DT bindings
From: Andreas Dannenberg
Date: Tue Apr 26 2016 - 13:01:22 EST
On Tue, Apr 26, 2016 at 05:50:06PM +0100, Mark Brown wrote:
> On Tue, Apr 26, 2016 at 11:14:25AM -0500, Andreas Dannenberg wrote:
> > On Tue, Apr 26, 2016 at 04:37:07PM +0100, Mark Brown wrote:
> > > On Mon, Apr 25, 2016 at 03:17:35PM -0500, Andreas Dannenberg wrote:
>
> > > > +Optional properties:
>
> > > > +- dvdd-supply : phandle to a 3.3-V supply for the digital circuitry
> > > > +- pvdd-supply : phandle to a supply used for the Class-D amp and the analog
>
> > > This suggests that the device doesn't need power...
>
> > no power, now that would be nice! :) What this was supposed to mean is
> > that the properties are optional, the power of course is not. The DT has
>
> They should only be optional if they may really be missing. We may
> attempt to be liberal in the DTs we accept but we should not encourage
> sloppily written DTs.
Thanks for the guidance and the background. Will move them to "required"
but I'll wait a few more days before re-submitting in case there is
additional feedback on the patch series.
Regards,
Andreas
>
> > really no control over how I wire up my HW and I'd argue most folks just
> > permanently power the TAS5720 since the shutdown current is just a few
> > uAs IIRC in order to save some BOM cost. But I suppose the DT description
> > is such that the Kernel can more intelligently handle things based on
> > what the driver is doing if somebody choses and implements additional
> > regulator/power switch HW. Or did I misunderstand your point?
>
> It doesn't really matter if a given system ends up controlling things
> actively, we still want to be consistent in describing them since it is
> less error prone when it does become relevant.