Hi Clement, Uwe,

On Mon, Nov 04, 2019 at 09:03:59AM +0100, Uwe Kleine-König wrote:
> On Sun, Nov 03, 2019 at 09:33:28PM +0100, Clément Péron wrote:
> > From: Jernej Skrabec <jernej.skrabec@siol.net>
> >
> > H6 PWM block is basically the same as A20 PWM, except that it also has
> > bus clock and reset line which needs to be handled accordingly.
> >
> > Expand Allwinner PWM binding with H6 PWM specifics.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
> > Signed-off-by: Clément Péron <peron.clem@gmail.com>
> > ---
> >  .../bindings/pwm/allwinner,sun4i-a10-pwm.yaml | 45 ++++++++++++++++++-
> >  1 file changed, 44 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/devicetree/bindings/pwm/allwinner,sun4i-a10-pwm.yaml b/Documentation/devicetree/bindings/pwm/allwinner,sun4i-a10-pwm.yaml
> > index 0ac52f83a58c..bf36ea509f31 100644
> > --- a/Documentation/devicetree/bindings/pwm/allwinner,sun4i-a10-pwm.yaml
> > +++ b/Documentation/devicetree/bindings/pwm/allwinner,sun4i-a10-pwm.yaml
> > @@ -30,13 +30,46 @@ properties:
> >        - items:
> >            - const: allwinner,sun50i-h5-pwm
> >            - const: allwinner,sun5i-a13-pwm
> > +      - const: allwinner,sun50i-h6-pwm
> >
> >    reg:
> >      maxItems: 1
> >
> > -  clocks:
> > +  # Even though it only applies to subschemas under the conditionals,
> > +  # not listing them here will trigger a warning because of the
> > +  # additionalsProperties set to false.
> > +  clocks: true
> > +  clock-names: true
> > +  resets:
> >      maxItems: 1
> >
> > +  if:
> > +    properties:
> > +      compatible:
> > +        contains:
> > +          const: allwinner,sun50i-h6-pwm
> > +
> > +  then:
> > +    properties:
> > +      clocks:
> > +        items:
> > +          - description: Module Clock
> > +          - description: Bus Clock
> > +
> > +      clock-names:
> > +        items:
> > +          - const: mod
> > +          - const: bus
> > +
> > +    required:
> > +      - clock-names
> > +      - resets
> > +
> > +  else:
> > +    properties:
> > +      clocks:
> > +        maxItems: 1
> > +
>
> I guess this hunk says "If this is a allwinner,sun50i-h6-pwm, a mod and
> bus clock is required.", right?
>
> I wonder if it is sensible to require a clock-names property in the else
> branch, too. This would make it obvious if the clock there corresponds
> to the "mod" or the "bus" clock on H6. (I guess it's "mod".)

This can be done a bit differently and could address your concerns

Something like

properties:
  ...

  clocks:
    minItems: 1
    maxItems: 2
    items:
      - description: Bus Clock
      - description: Module Clock

required:
  - clocks

if:
  ...

then:
  properties:
    clocks:
      maxItems: 2

    clocks-names:
      items:
        - const: mod
        - const: bus

    required:
      - clock-names

else:
  properties:
    clocks:
      maxItems: 1

That way, the definition of the order and which clock is which is
pretty obvious in both cases, and we don't get any weird warnings.

Maxime