[alsa-devel] [PATCH v2 4/6] dt-bindings: misc: atmel-ssc: LRCLK from TF/RF pin option

[Rob Herring]

On Wed, Aug 28, 2019 at 8:03 AM Michał Mirosław <mirq-linux at rere.qmqm.pl> wrote:
>
> On Tue, Aug 27, 2019 at 05:37:16PM -0500, Rob Herring wrote:
> > On Sat, Aug 24, 2019 at 10:26:55PM +0200, Michał Mirosław wrote:
> > > Add single-pin LRCLK source options for Atmel SSC module.
> > >
> > > Signed-off-by: Michał Mirosław <mirq-linux at rere.qmqm.pl>
> > >
> > > ---
> > >   v2: split from implementation patch
> > >
> > > ---
> > >  Documentation/devicetree/bindings/misc/atmel-ssc.txt | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/misc/atmel-ssc.txt b/Documentation/devicetree/bindings/misc/atmel-ssc.txt
> > > index f9fb412642fe..c98e96dbec3a 100644
> > > --- a/Documentation/devicetree/bindings/misc/atmel-ssc.txt
> > > +++ b/Documentation/devicetree/bindings/misc/atmel-ssc.txt
> > > @@ -24,6 +24,11 @@ Optional properties:
> > >         this parameter to choose where the clock from.
> > >       - By default the clock is from TK pin, if the clock from RK pin, this
> > >         property is needed.
> > > +  - atmel,lrclk-from-tf-pin: bool property.
> > > +  - atmel,lrclk-from-rf-pin: bool property.
> > > +     - SSC in slave mode gets LRCLK from RF for receive and TF for transmit
> > > +       data direction. This property makes both use single TF (or RF) pin
> > > +       as LRCLK. At most one can be present.
> >
> > A single property taking 1 of possible 2 values would prevent the error
> > of more than 1 property present.
>
> It still would need a validation check in the code, though: you
> could put wrong value then.  It seems more consistent with the
> existing parameters to have two bool properties.

It was validation using schema that I was thinking about. Expressing a
possible set of values for a property is easier than inter-property
constraints.

But if you really prefer as-is:

Reviewed-by: Rob Herring <robh at kernel.org>