Re: [PATCH RFC 3/7] dt-bindings: mfd: rz-mtu3: Document RZ/G2L MTU3 PWM

[Lee Jones <lee@kernel.org>]

On Thu, 29 Sep 2022, Biju Das wrote:

> Hi Lee Jones,
> 
> Thanks for the feedback.
> 
> > Subject: Re: [PATCH RFC 3/7] dt-bindings: mfd: rz-mtu3: Document
> > RZ/G2L MTU3 PWM
> > 
> > On Thu, 29 Sep 2022, Biju Das wrote:
> > 
> > > Document RZ/G2L MTU3 PWM support. It supports following pwm modes.
> > > 	1) PWM mode 1
> > > 	2) PWM mode 2
> > > 	3) Reset-synchronized PWM mode
> > > 	4) Complementary PWM mode 1 (transfer at crest)
> > > 	5) Complementary PWM mode 2 (transfer at trough)
> > > 	6) Complementary PWM mode 3 (transfer at crest and trough)
> > 
> > Shouldn't all this go in the PWM driver binding?
> 
> Looks like at top level MTU3 IP provides similar HW functionality like below
> binding [1], where there is a core MFD driver and pwm, counter and timer
> as child devices.

Previous mistakes are not good references for what should happen in
the present and the future. =;)

> [1] https://elixir.bootlin.com/linux/v6.0-rc7/source/Documentation/devicetree/bindings/mfd/st,stm32-timers.yaml
> 
> Cheers,
> Biju
> > 
> > > Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> > > ---
> > >  .../bindings/mfd/renesas,rzg2l-mtu3.yaml      | 50
> > +++++++++++++++++++
> > >  1 file changed, 50 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/mfd/renesas,rzg2l-
> > mtu3.yaml b/Documentation/devicetree/bindings/mfd/renesas,rzg2l-
> > mtu3.yaml
> > > index c4bcf28623d6..362fedf5bedb 100644
> > > --- a/Documentation/devicetree/bindings/mfd/renesas,rzg2l-mtu3.yaml
> > > +++ b/Documentation/devicetree/bindings/mfd/renesas,rzg2l-mtu3.yaml
> > > @@ -223,6 +223,50 @@ patternProperties:
> > >        - compatible
> > >        - reg
> > >
> > > +  "^pwm@([0-4]|[6-7])+$":
> > > +    type: object
> > > +
> > > +    properties:
> > > +      compatible:
> > > +        const: renesas,rz-mtu3-pwm
> > > +
> > > +      reg:
> > > +        description: Identify pwm channels.
> > > +        items:
> > > +          enum: [ 0, 1, 2, 3, 4, 6, 7 ]
> > > +
> > > +      "#pwm-cells":
> > > +        const: 2
> > > +
> > > +      renesas,pwm-mode1:
> > > +        type: boolean
> > > +        description: Enable PWM mode 1.
> > > +
> > > +      renesas,pwm-mode2:
> > > +        type: boolean
> > > +        description: Enable PWM mode 2.
> > > +
> > > +      renesas,reset-synchronized-pwm-mode:
> > > +        type: boolean
> > > +        description: Enable Reset-synchronized PWM mode.
> > > +
> > > +      renesas,complementary-pwm-mode1:
> > > +        type: boolean
> > > +        description: Complementary PWM mode 1 (transfer at crest).
> > > +
> > > +      renesas,complementary-pwm-mode2:
> > > +        type: boolean
> > > +        description: Complementary PWM mode 2 (transfer at trough).
> > > +
> > > +      renesas,complementary-pwm-mode3:
> > > +        type: boolean
> > > +        description: Complementary PWM mode 3 (transfer at crest
> > and trough).
> > > +
> > > +    required:
> > > +      - compatible
> > > +      - reg
> > > +      - "#pwm-cells"
> > > +
> > >  required:
> > >    - compatible
> > >    - reg
> > > @@ -305,6 +349,12 @@ examples:
> > >          compatible = "renesas,rzg2l-mtu3-counter";
> > >          reg = <1>;
> > >        };
> > > +      pwm@3 {
> > > +        compatible = "renesas,rz-mtu3-pwm";
> > > +        reg = <3>;
> > > +        #pwm-cells = <2>;
> > > +        renesas,pwm-mode1;
> > > +      };
> > >      };
> > >
> > >  ...
> > 

-- 
Lee Jones [李琼斯]