driver: pwm/pca9685: handle POLARITY flag

Handle polarity flag in pca9685 driver

Signed-off-by: Franck Duriez <[email protected]>

Author: franckduriez

boards/shields/adafruit_pca9685/adafruit_pca9685.overlay

@@ -13,7 +13,7 @@
 		status = "okay";
 		compatible = "nxp,pca9685-pwm";
 		reg = <0x40>;
-		#pwm-cells = <2>;
+		#pwm-cells = <3>;
 	};
 };
 

drivers/pwm/pwm_pca9685.c

@@ -173,7 +173,9 @@ static int pca9685_set_cycles(const struct device *dev,
 	int32_t pre_scale;
 	int ret;
 
-	ARG_UNUSED(flags);
+	if (flags & PWM_POLARITY_INVERTED) {
+		pulse_count = period_count - pulse_count;
+	}
 
 	if (channel >= CHANNEL_CNT) {
 		LOG_WRN("channel out of range: %u", channel);

dts/bindings/pwm/nxp,pca9685.yaml

@@ -30,8 +30,9 @@ properties:
       used.
 
   "#pwm-cells":
-    const: 2
+    const: 3
 
 pwm-cells:
   - channel
   - period
+  - flags

tests/drivers/build_all/pwm/boards/native_sim.overlay

@@ -33,7 +33,7 @@
 				status = "okay";
 				compatible = "nxp,pca9685-pwm";
 				reg = <0x1>;
-				#pwm-cells = <2>;
+				#pwm-cells = <3>;
 			};
 		};
 	};