Re: [PATCH 1/2] dt-bindings: input: gpio-keys: add pinctrl states

[Kendall Willis <k-willis@ti.com>]

On 19:07-20260915, Krzysztof Kozlowski wrote:
> On 15/09/2026 19:05, Krzysztof Kozlowski wrote:
> > On 15/09/2026 18:48, Kendall Willis wrote:
> >> On 12:13-20260914, Krzysztof Kozlowski wrote:
> >>> On Sat, Sep 12, 2026 at 04:33:53PM -0500, Kendall Willis wrote:
> >>>> Document pinctrl properties on the gpio-keys device node. By using the
> >>>> wakeup pinctrl state, the pins are able to wakeup the system from a
> >>>> low-power state. The default pinctrl state describes the default pin
> >>>> configuration.
> >>>>
> >>>> Signed-off-by: Kendall Willis <k-willis@ti.com>
> >>>> ---
> >>>>  Documentation/devicetree/bindings/input/gpio-keys.yaml | 16 ++++++++++++++++
> >>>>  1 file changed, 16 insertions(+)
> >>>>
> >>>> diff --git a/Documentation/devicetree/bindings/input/gpio-keys.yaml b/Documentation/devicetree/bindings/input/gpio-keys.yaml
> >>>> index cc78c2152921308fe0cad3e29ca78a5fad08f066..b554933e93412d8b6c2ec401dc1e1eeff57d4190 100644
> >>>> --- a/Documentation/devicetree/bindings/input/gpio-keys.yaml
> >>>> +++ b/Documentation/devicetree/bindings/input/gpio-keys.yaml
> >>>> @@ -22,6 +22,22 @@ properties:
> >>>>  
> >>>>    poll-interval: true
> >>>>  
> >>>> +  pinctrl-0:
> >>>> +    description: Default pinctrl state
> >>>> +
> >>>> +  pinctrl-1:
> >>>> +    description: Wakeup pinctrl state
> >>>> +
> >>>> +  pinctrl-names:
> >>>> +    description:
> >>>> +      When present should contain at least "default" describing the default pin
> >>>> +      states. The second state called "wakeup" describes the pins in their
> >>>> +      wakeup configuration required to exit sleep states.
> >>>> +    minItems: 1
> >>>> +    items:
> >>>> +      - const: default
> >>>> +      - const: wakeup
> >>>
> >>> This will introduce new warnings, which should be being fixed in this
> >>> patchset (e.g. at91-kizbox3-hs.dts).
> >>>
> >>
> >> Will fix the binding to work with current device trees.
> >>
> >>> But nevertheless, isn't second state the sleep state? How can you
> >>> configure pins for the wakeup state - like being in the wakeup? You
> >>> configure the pins for given state, which will be a system suspend, so
> >>> sleep?
> >>>
> >>
> >> The sleep state usually refers to putting the pins in a state to save
> >> power. The wakeup pinctrl state is for putting the pins in a state to
> >> allow wakeup from suspend for that device. Both 'sleep' and 'wakeup'
> >> are for system suspend, but they fill different functions. The CAN
> >> subsystem also uses the 'wakeup' state in addition to the 'sleep' state
> >> [1].
> > 
> > So you mean sleep would be a separate state? But then aren't both
> > exactly the same states? IOW, if device is wakeup-source, it will have
> > for "sleep" state pin configuration allowing to wakeup.

The 'sleep' and 'wakeup' pin states are both used for suspend. They
would just be used separately since only one could be used at a time.
The reason 'wakeup' is separated out is because it is more specific for
allowing wakeup from the device.

> 
> And about CAN, I see no use of both sleep and wakeup:
> git grep pinctrl-names | grep wakeup
> 
> So if you use existing code as reason for this change, then existing
> code tells they are the same.
> 

Yes, as of now both are not being used at the same time. I was more
pointing to existing code to show that the 'wakeup' pinctrl state was
being used for wakeup pin configurations.

Best,
Kendall