Re: [PATCH 1/1] arm64: dts: imx8mp-skov: add pinctrl-name 'reset' to fix CHECK_DTB warning

[Marco Felsch <m.felsch@pengutronix.de>]

Hi Peng,

On 26-01-06, Peng Fan wrote:
> Hi Marco,
> 
> On Mon, Jan 05, 2026 at 12:14:48PM +0100, Marco Felsch wrote:
> >Hi Frank,
> >
> >On 25-12-29, Frank Li wrote:
> >> Add pinctrl-name 'reset' to fix below CHECK_DTB warnings:
> >>   arch/arm64/boot/dts/freescale/imx8mp-skov-basic.dtb: switch@5f (microchip,ksz9893): pinctrl-names: ['default'] is too short
> >> 	from schema $id: http://devicetree.org/schemas/net/dsa/microchip,ksz.yaml#
> >> 
> >> The commit (e469b87e0fb0d dt-bindings: net: dsa: microchip: Add strap
> >> description to set SPI mode" force use two pinctrl-name 'default' and
> >> 'reset'. switch@5f doesn't use SPI, so it is safe to use the same pinctrl
> >> setting for both.
> >
> >please see:
> >- https://lore.kernel.org/all/20251112084717.ea7fchu7jcz6dzsi@pengutronix.de/
> >
> >I stumbled over the same warning, but came to the conclusion, that the
> >dt-bindings should be fixed instead of workaround broken bindings within
> >the dtb.
> 
> If reset is optional, the dt-bindings should include "minItems:1" per my
> understanding.

Not sure, since the pinctrl-names is just an enum list. That beeing
said, I don't see it as required since the strapping may not be required
for systems which do already has correct ext. strapping options.
Therefore the binding should be always optional and the driver should be
adapted.

> But..
> 
> >
> >> -		pinctrl-names = "default";
> >> -		pinctrl-0 = <&pinctrl_switch>;
> >> +		pinctrl-names = "default", "reset";
> >> +		pinctrl-0 = <&pinctrl_switch>, <&pinctrl_switch>;
> 
> Per checking
> https://elixir.bootlin.com/linux/v6.18.3/source/drivers/net/dsa/microchip/ksz_common.c#L5372
> 
> seems "reset" is required in driver.

For the ksz8463 but not for the ksz9893 which is used by the
imx8mp-skov-reva.dtsi (here).

Regards,
  Marco




> 
> Regards
> Peng
> 
> >>  		reset-gpios = <&gpio5 1 GPIO_ACTIVE_LOW>;
> >>  		reg = <0x5f>;
> >>  
> >> -- 
> >> 2.34.1
> >> 
> >> 
> >> 
> >
> >-- 
> >#gernperDu 
> >#CallMeByMyFirstName
> >
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> 

-- 
#gernperDu 
#CallMeByMyFirstName

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