Re: [PATCH v2 2/8] dt-bindings: counter: Add new ti,am62-eqep compatible

[Judith Mendez]

On 5/24/24 3:57 PM, David Lechner wrote:
> On 5/24/24 3:50 PM, David Lechner wrote:
> > On 5/23/24 6:15 PM, Judith Mendez wrote:
> > > Add new compatible ti,am62-eqep for TI K3 devices. If a device
> > > uses this compatible, require power-domains property.
> > >
> > > Since there is only one functional and interface clock for eqep,
> > > clock-names is not really required. The clock-name also changed
> > > for TI K3 SoCs so make clock-names optional for the new compatible
> > > since there is only one clock that is routed to the IP.
> > >
> > > While we are here, add an example using ti,am62-eqep compatible.
> > >
> > > Signed-off-by: Judith Mendez <jm@xxxxxx>
> > > ---
> > > Changes since v1:
> > > - Fix eqep binding for new compatible, require
> > >   power-domains for new compatible
> > > ---
> > >   .../devicetree/bindings/counter/ti-eqep.yaml  | 53 +++++++++++++++++--
> > >   1 file changed, 48 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/counter/ti-eqep.yaml b/Documentation/devicetree/bindings/counter/ti-eqep.yaml
> > > index 85f1ff83afe72..c4bb0231f166a 100644
> > > --- a/Documentation/devicetree/bindings/counter/ti-eqep.yaml
> > > +++ b/Documentation/devicetree/bindings/counter/ti-eqep.yaml
> > > @@ -11,7 +11,9 @@ maintainers:
> > >   
> > >   properties:
> > >     compatible:
> > > -    const: ti,am3352-eqep
> > > +    enum:
> > > +      - ti,am3352-eqep
> > > +      - ti,am62-eqep
> > >   
> > >     reg:
> > >       maxItems: 1
> > > @@ -21,19 +23,43 @@ properties:
> > >       maxItems: 1
> > >   
> > >     clocks:
> > > -    description: The clock that determines the SYSCLKOUT rate for the eQEP
> > > -      peripheral.
> > > +    description: The functional and interface clock that determines the clock
> > > +      rate for the eQEP peripheral.
> > >       maxItems: 1
> > >   
> > >     clock-names:
> > > -    const: sysclkout
> > > +    enum:
> > > +      - sysclkout
> > > +      - fck
> > > +
> >
> > If we are making this optional for ti,am62-eqep, why add a new name?
> >
> > Also, we could change the description to say that sysclockout is not a
> > great name but is required for backwards compatibility.
> >
> > > +  power-domains:
> > > +    maxItems: 1
> > > +
> > > +allOf:
> > > +  - if:
> > > +      properties:
> > > +        compatible:
> > > +          contains:
> > > +            enum:
> > > +              - ti,am3352-eqep
> > > +    then:
> > > +      required:
> > > +        - clock-names
>
> I just looked at the Linux driver for this and the clock name is
> not used in the driver. So we could probably just deprecate the
> clock-names property here and not make it required for
> ti,am3352-eqep (and not allowed for any new compatibles as
> suggested below).

We could do this, although I was under the impression that we should
not drop DT properties just because the linux driver isn't using it,
that is why I went with keeping clock-names around for am335x compatible
and making it optional for am62x compatible.

But if it is all the same, we could drop the the DT property.

~ Judith

> > What if we just add
> >
> >    else:
> >      clock-names: false
> >
> > since there is only one clock and not worry about the name?
> >
> > > +  - if:
> > > +      properties:
> > > +        compatible:
> > > +          contains:
> > > +            enum:
> > > +              - ti,am62-eqep
> > > +    then:
> > > +      required:
> > > +        - power-domains
> > >   
> > >   required:
> > >     - compatible
> > >     - reg
> > >     - interrupts
> > >     - clocks
> > > -  - clock-names
> > >