Some PWM LED driver chips like TPS92380 and LT3743 require a separate
enable signal in addition to PWM control. Add this property to allow
device trees to specify such GPIO, which will be controlled automatically
by the driver based on the LED brightness state.

Link: https://www.ti.com/lit/gpn/tps92380
Link: https://www.analog.com/media/en/technical-documentation/data-sheets/3743fe.pdf

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: LI Qingwu <Qing-wu.Li@leica-geosystems.com.cn>
---
 Documentation/devicetree/bindings/leds/leds-pwm.yaml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/leds/leds-pwm.yaml b/Documentation/devicetree/bindings/leds/leds-pwm.yaml
index 61b97e8bc36d0..6c4fcefbe25f9 100644
--- a/Documentation/devicetree/bindings/leds/leds-pwm.yaml
+++ b/Documentation/devicetree/bindings/leds/leds-pwm.yaml
@@ -40,6 +40,13 @@ patternProperties:
           initialization. If the option is not set then max brightness is used.
         $ref: /schemas/types.yaml#/definitions/uint32
 
+      enable-gpios:
+        description:
+          GPIO for LED hardware enable control. Set active when brightness is
+          non-zero and inactive when brightness is zero.
+          The GPIO default state follows the "default-state" property.
+        maxItems: 1
+
     required:
       - pwms
       - max-brightness
-- 
2.43.0