boards: arm: twr_ke18f: add PWM LEDs

Add support for driving the on-board LEDs present on the NXP TWR-KE18F
development board using FlexTimer (FTM) PWM modulation.

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>

boards/arm/twr_ke18f/Kconfig.defconfig

@@ -89,4 +89,14 @@ config ADC_0
 
 endif # ADC
 
+if PWM
+
+config PWM_0
+	default y
+
+config PWM_3
+	default y
+
+endif # PWM
+
 endif # BOARD_TWR_KE18F

boards/arm/twr_ke18f/doc/index.rst

@@ -82,6 +82,8 @@ features:
 +-----------+------------+-------------------------------------+
 | WDT       | on-chip    | watchdog                            |
 +-----------+------------+-------------------------------------+
+| PWM       | on-chip    | pwm                                 |
++-----------+------------+-------------------------------------+
 
 The default configuration can be found in the defconfig file:
 ``boards/arm/twr_ke18f/twr_ke18f_defconfig``.

boards/arm/twr_ke18f/pinmux.c

@@ -34,14 +34,31 @@ static int twr_ke18f_pinmux_init(struct device *dev)
 		device_get_binding(CONFIG_PINMUX_MCUX_PORTE_NAME);
 #endif
 
-	/* LEDs */
+#ifdef CONFIG_PWM_0
+	/* Tri-color LED as PWM */
+	pinmux_pin_set(portb, 5, PORT_PCR_MUX(kPORT_MuxAlt2));
+	pinmux_pin_set(portd, 15, PORT_PCR_MUX(kPORT_MuxAlt2));
+	pinmux_pin_set(portd, 16, PORT_PCR_MUX(kPORT_MuxAlt2));
+#else /* !CONFIG_PWM_0 */
+	/* Tri-color LED as GPIO */
 	pinmux_pin_set(portb, 5, PORT_PCR_MUX(kPORT_MuxAsGpio));
+	pinmux_pin_set(portd, 15, PORT_PCR_MUX(kPORT_MuxAsGpio));
+	pinmux_pin_set(portd, 16, PORT_PCR_MUX(kPORT_MuxAsGpio));
+#endif /* !CONFIG_PWM_0 */
+
+#ifdef CONFIG_PWM_3
+	/* User LEDs as PWM */
+	pinmux_pin_set(portc, 10, PORT_PCR_MUX(kPORT_MuxAlt2));
+	pinmux_pin_set(portc, 11, PORT_PCR_MUX(kPORT_MuxAlt2));
+	pinmux_pin_set(portc, 12, PORT_PCR_MUX(kPORT_MuxAlt2));
+	pinmux_pin_set(portc, 13, PORT_PCR_MUX(kPORT_MuxAlt2));
+#else /* !CONFIG_PWM_3 */
+	/* User LEDs as GPIO */
 	pinmux_pin_set(portc, 10, PORT_PCR_MUX(kPORT_MuxAsGpio));
 	pinmux_pin_set(portc, 11, PORT_PCR_MUX(kPORT_MuxAsGpio));
 	pinmux_pin_set(portc, 12, PORT_PCR_MUX(kPORT_MuxAsGpio));
 	pinmux_pin_set(portc, 13, PORT_PCR_MUX(kPORT_MuxAsGpio));
-	pinmux_pin_set(portd, 15, PORT_PCR_MUX(kPORT_MuxAsGpio));
+#endif /* !CONFIG_PWM_3 */
-	pinmux_pin_set(portd, 16, PORT_PCR_MUX(kPORT_MuxAsGpio));
 
 	/* Buttons */
 	pinmux_pin_set(portd, 3, PORT_PCR_MUX(kPORT_MuxAsGpio));

boards/arm/twr_ke18f/twr_ke18f.dts

@@ -21,6 +21,13 @@
 		led4 = &tri_red_led;
 		led5 = &tri_green_led;
 		led6 = &tri_blue_led;
+		pwm-led0 = &orange_pwm_led;
+		pwm-led1 = &yellow_pwm_led;
+		pwm-led2 = &green_pwm_led;
+		pwm-led3 = &red_pwm_led;
+		red-pwm-led = &tri_red_pwm_led;
+		green-pwm-led = &tri_green_pwm_led;
+		blue-pwm-led = &tri_blue_pwm_led;
 		sw0 = &user_button_3;
 		sw1 = &user_button_2;
 	};
@@ -67,6 +74,39 @@
 		};
 	};
 
+	pwmleds {
+		compatible = "pwm-leds";
+		orange_pwm_led: led_pwm_0 {
+			pwms = <&ftm3 7 60000>;
+			label = "User PWM LED D9";
+		};
+		yellow_pwm_led: led_pwm_1 {
+			pwms = <&ftm3 6 60000>;
+			label = "User PWM LED D8";
+		};
+		green_pwm_led: led_pwm_2 {
+			pwms = <&ftm3 5 60000>;
+			label = "User PWM LED D7";
+		};
+		red_pwm_led: led_pwm_3 {
+			pwms = <&ftm3 4 60000>;
+			label = "User PWM LED D6";
+		};
+
+		tri_red_pwm_led: led_pwm_4 {
+			pwms = <&ftm0 1 60000>;
+			label = "User Tricolor PWM LED D5 (Red)";
+		};
+		tri_green_pwm_led: led_pwm_5 {
+			pwms = <&ftm0 0 60000>;
+			label = "User Tricolor PWM LED D5 (Green)";
+		};
+		tri_blue_pwm_led: led_pwm_6 {
+			pwms = <&ftm0 5 60000>;
+			label = "User Tricolor PWM LED D5 (Blue)";
+		};
+	};
+
 	gpio_keys {
 		compatible = "gpio-keys";
 		user_button_2: button_0 {
@@ -118,6 +158,14 @@
 	current-speed = <115200>;
 };
 
+&ftm0 {
+	status = "okay";
+};
+
+&ftm3 {
+	status = "okay";
+};
+
 &i2c0 {
 	status = "okay";
 

boards/arm/twr_ke18f/twr_ke18f.yaml

@@ -17,3 +17,4 @@ supported:
   - adc
   - can
   - watchdog
+  - pwm