dt-bindings: leds: Add 'active-high' property

Other than described in commit c94d178313 ("dt-bindings: net: phy:
Make LED active-low property common") the absence of the 'active-low'
property means not to touch the polarity settings which are inherited
from reset defaults, the bootloader or bootstrap configuration. Hence,
in order to override a LED pin being active-high in case of the default,
bootloader or bootstrap setting being active-low an additional property
'active-high' is required. Document that property and make it mutually
exclusive to the existing 'active-low' property.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/e9b15613a81129ceecb07ec51f71bbe75425ad2e.1728558223.git.daniel@makrotopia.org
Signed-off-by: Lee Jones <lee@kernel.org>

Documentation/devicetree/bindings/leds/common.yaml

@@ -204,6 +204,12 @@ properties:
       #trigger-source-cells property in the source node.
     $ref: /schemas/types.yaml#/definitions/phandle-array
 
+  active-high:
+    type: boolean
+    description:
+      Makes LED active high. To turn the LED ON, line needs to be
+      set to high voltage instead of low.
+
   active-low:
     type: boolean
     description:
@@ -227,6 +233,14 @@ properties:
       Maximum timeout in microseconds after which the flash LED is turned off.
       Required for flash LED nodes with configurable timeout.
 
+allOf:
+  - if:
+      required:
+        - active-low
+    then:
+      properties:
+        active-high: false
+
 additionalProperties: true
 
 examples: