Re: [PATCH] dt-bindings: pinctrl: mt8192: Add mediatek,pull-down-adv property

From: "Nícolas F. R. A. Prado" <nfraprado@collabora.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>,
	kernel@collabora.com,
	AngeloGioacchino Del Regno 
	<angelogioacchino.delregno@collabora.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Rob Herring <robh+dt@kernel.org>,
	Sean Wang <sean.wang@mediatek.com>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-mediatek@lists.infradead.org
Subject: Re: [PATCH] dt-bindings: pinctrl: mt8192: Add mediatek,pull-down-adv property
Date: Tue, 17 May 2022 17:31:11 -0400	[thread overview]
Message-ID: <20220517213111.22slqxqhbaxc22f6@notapiano> (raw)
In-Reply-To: <4adf790c-5773-a78e-3c8e-2a510e3dbd1e@linaro.org>

On Fri, Apr 29, 2022 at 10:31:52PM +0200, Krzysztof Kozlowski wrote:
> On 29/04/2022 22:06, Nícolas F. R. A. Prado wrote:
> > Add the mediatek,pull-down-adv property to the pinctrl-mt8192 dt-binding
> > to allow configuring pull-down resistors on the pins of MT8192. It is
> > the same as in mt8183-pinctrl.
> > 
> > Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> > 
> > ---
> > 
> >  .../devicetree/bindings/pinctrl/pinctrl-mt8192.yaml   | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
> > index c90a132fbc79..e462f49eae6f 100644
> > --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
> > +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
> > @@ -117,6 +117,17 @@ patternProperties:
> >              $ref: /schemas/types.yaml#/definitions/uint32
> >              enum: [0, 1, 2, 3]
> >  
> > +          mediatek,pull-down-adv:
> > +            description: |
> > +              Pull down settings for 2 pull resistors, R0 and R1. User can
> > +              configure those special pins. Valid arguments are described as below:
> 
> Trailing ':' should be escaped, so '::'

OK.

> 
> 
> > +              0: (R1, R0) = (0, 0) which means R1 disabled and R0 disabled.
> > +              1: (R1, R0) = (0, 1) which means R1 disabled and R0 enabled.
> > +              2: (R1, R0) = (1, 0) which means R1 enabled and R0 disabled.
> > +              3: (R1, R0) = (1, 1) which means R1 enabled and R0 enabled.
> > +            $ref: /schemas/types.yaml#/definitions/uint32
> > +            enum: [0, 1, 2, 3]
> 
> It's okay, but for all these and other values (you have few such in the
> binding), you should maybe add header and defines. It's much more
> readable for humans...

OK. I'll look into adding defines for these.

> 
> Is the property valid without bias-pull-down?

Actually it doesn't really make sense to set this property together with
bias-pull-down, as they set conflicting register settings for the pin bias...
I'll add a condition to avoid both being present.

Thanks,
Nícolas

> 
> Best regards,
> Krzysztof