Re: [PATCH 1/4] ASoC: dt-bindings: Add Cadence I2S-SC controller

[Rob Herring]

On Thu, Sep 24, 2026 at 07:33:12AM +0000, Joakim  Zhang (张强庆) wrote:
> 
> Hello,
> 
> > -----Original Message-----
> > From: Mark Brown <broonie@xxxxxxxxxx>
> > Sent: Tuesday, September 22, 2026 10:24 PM
> > To: Joakim Zhang (张强庆) <joakim.zhang@xxxxxxxxxxx>
> > Cc: lgirdwood@xxxxxxxxx; robh@xxxxxxxxxx; krzk+dt@xxxxxxxxxx;
> > conor+dt@xxxxxxxxxx; perex@xxxxxxxx; tiwai@xxxxxxxx; p.zabel@xxxxxxxxxxxxxx;
> > cix-kernel-upstream <cix-kernel-upstream@xxxxxxxxxxx>; linux-
> > sound@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > Subject: Re: [PATCH 1/4] ASoC: dt-bindings: Add Cadence I2S-SC controller
> > 
> > On Tue, Sep 22, 2026 at 07:21:31PM +0800, joakim.zhang@xxxxxxxxxxx wrote:
> > 
> > > Add the DT binding for the Cadence I2S-SC controller integrated in the
> > > CIX SKY1 audio subsystem. I2S-SC is a full-duplex stereo controller
> > > supporting standard I2S, left/right-justified and DSP formats, plus
> > > TDM operation with up to 16 slots.
> > 
> > > +properties:
> > > +  compatible:
> > > +    const: cix,sky1-i2s-sc
> > 
> > Should there be some general Cadence fallback for this if it's a Cadence IP?
> 
> Yes, cdns,sky1-i2s-sc should be better.

No. Cadence has nothing to do with sky1. It would be the above *plus* a 
Cadence fallback compatible.

I'm on the fence whether a Cadence compatible is useful. For complex IP 
(e.g. PCIe, USB, etc.), IP vendor fallbacks have proven to be not 
useful. For simple IP blocks, they can be useful. It also depends if 
there is a h/w manual which can be used so we can really define the 
correct numbers of clocks, interrupts, etc. Perhaps I2S is simple 
enough.

Rob