RE: [PATCH v3 1/7] dt-bindings: pincfg-node: Add input-voltage-microvolt property

["Yu-Chun Lin [林祐君]" <eleanor.lin@realtek.com>]

> On Thu, Mar 12, 2026 at 05:42:31PM +0000, Conor Dooley wrote:
>> On Thu, Mar 12, 2026 at 07:30:34PM +0800, Yu-Chun Lin wrote:
>>> From: Tzuyi Chang <tychang@realtek.com>
>>> 
>>> Add a generic pin configuration property "input-voltage-microvolt" 
>>> to support hardware designs where the input logic threshold is 
>>> decoupled from the power supply voltage.
>>> 
>>> This property allows the pinctrl driver to configure the correct 
>>> internal reference voltage for pins that need to accept input 
>>> signals at a different voltage level than their power supply. For 
>>> example, a pin powered by 3.3V may need to accept 1.8V logic signals.
>>> 
>>> This defines the reference for VIH (Input High Voltage) and VIL 
>>> (Input Low
>>> Voltage) thresholds, enabling proper signal detection across 
>>> different voltage domains.
>>> 
>>> Signed-off-by: Tzuyi Chang <tychang@realtek.com>
>>> Co-developed-by: Yu-Chun Lin <eleanor.lin@realtek.com>
>>> Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
>>> ---
>>> Changes in v3:
>>> - Rebased onto the devel branch of the pinctrl tree.
>>> - Improved commit message and description.
>>> ---
>>>  Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml | 5 
>>> +++++
>>>  1 file changed, 5 insertions(+)
>>> 
>>> diff --git 
>>> a/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml 
>>> b/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
>>> index fe936ab09104..fd49a0d53bf0 100644
>>> --- a/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
>>> +++ b/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
>>> @@ -162,6 +162,11 @@ properties:
>>>        this affects the expected delay in ps before latching a value to
>>>        an output pin.
>>>  
>>> +  input-voltage-microvolt:
>>> +    description: Specifies the input voltage level of the pin in microvolts.
>>> +      This defines the reference for  VIH (Input High Voltage) and VIL
>>> +      (Input Low Voltage) thresholds for proper signal detection.
>> 
>> Should this be added here:
>>   - if:
>>       required:
>>         - input-disable
>>     then:
>>       properties:
>>         input-enable: false
>> 
>> and made mutually exclusive with input-disable?
>

Yes, I will add the restrict as follows:
allOf:
  - if:
      required:
        - input-disable
    then:
      properties:
        input-enable: false
        input-voltage-microvolt: false

> Also looking at v1, should this be something like "input-threshold-voltage-microvolt"?
> "input-voltage-microvolt"? doesn't seem specific enough to the described use case.
>

Agreed. I will rename it to "input-threshold-voltage-microvolt" in v4.

Best Regards,
Yu-Chun

> 
>>> +
>>>  allOf:
>>>    - if:
>>>        required:
>>> --
>>> 2.34.1
>>>