dt-bindings: pincfg-node: Add property 'input-debounce-ns'

The StarFive JHB100 SoC hardware supports debounce time configuration
with nanosecond granularity. The existing 'input-debounce' property
uses microseconds, which is insufficient to accurately represent the
hardware's finer timing steps.

Add the property 'input-debounce-ns' to specify debounce time in
nanoseconds as an alternative to the existing 'input-debounce' which
uses microseconds. Make the new property unavailable when the existing
property 'input-debounce' is selected to prevent conflicting definitions.

Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Linus Walleij <linusw@kernel.org>

Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml

@@ -104,6 +104,10 @@ properties:
     description: Takes the debounce time in usec as argument or 0 to disable
       debouncing
 
+  input-debounce-ns:
+    description: Takes the debounce time in nsec as argument or 0 to disable
+      debouncing
+
   power-source:
     $ref: /schemas/types.yaml#/definitions/uint32
     description: select between different power supplies
@@ -214,6 +218,13 @@ allOf:
         input-schmitt-enable: false
         input-schmitt-microvolt: false
 
+  - if:
+      required:
+        - input-debounce
+    then:
+      properties:
+        input-debounce-ns: false
+
   - if:
       required:
         - drive-strength