[PATCH 2/2] arm64: dts: ti: k3-am625-sk: Use pwm-led instead of gpio-led

Tony Lindgren tony at atomide.com
Wed Sep 14 00:42:24 PDT 2022


On am625, pad c17 can be used either in gpio mode or pwm mode to control
the connected led. Let's change to use pwm-led for additional brighness
control.

The pwm controller is dmtimer7 for pad C17. We configure it for 128 Hz
rate (1000000000 / 7812500) similar to what has been done elsewhere for
pwm-leds.

Cc: Keerthy <j-keerthy at ti.com>
Cc: Nishanth Menon <nm at ti.com>
Cc: Vignesh Raghavendra <vigneshr at ti.com>
Signed-off-by: Tony Lindgren <tony at atomide.com>
---
 arch/arm64/boot/dts/ti/k3-am625-sk.dts | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/boot/dts/ti/k3-am625-sk.dts b/arch/arm64/boot/dts/ti/k3-am625-sk.dts
--- a/arch/arm64/boot/dts/ti/k3-am625-sk.dts
+++ b/arch/arm64/boot/dts/ti/k3-am625-sk.dts
@@ -131,18 +131,25 @@ vdd_sd_dv: regulator-4 {
 	};
 
 	leds {
-		compatible = "gpio-leds";
-		pinctrl-names = "default";
-		pinctrl-0 = <&usr_led_pins_default>;
+		compatible = "pwm-leds";
 
 		led-0 {
 			label = "am62-sk:green:heartbeat";
-			gpios = <&main_gpio1 49 GPIO_ACTIVE_HIGH>;
+			pwms = <&main_pwm7 0 7812500 0>;
+			max-brightness = <255>;
 			linux,default-trigger = "heartbeat";
 			function = LED_FUNCTION_HEARTBEAT;
 			default-state = "off";
 		};
 	};
+
+	main_pwm7: dmtimer-main-pwm-7 {
+		pinctrl-0 = <&usr_led_pins_default>;
+		pinctrl-names = "default";
+		compatible = "ti,omap-dmtimer-pwm";
+		#pwm-cells = <3>;
+		ti,timers = <&main_timer7>;
+	};
 };
 
 &main_pmx0 {
@@ -203,7 +210,7 @@ AM62X_IOPAD(0x240, PIN_INPUT, 0) /* (D17) MMC1_SDCD */
 
 	usr_led_pins_default: usr-led-pins-default {
 		pinctrl-single,pins = <
-			AM62X_IOPAD(0x244, PIN_OUTPUT, 7) /* (C17) MMC1_SDWP.GPIO1_49 */
+			AM62X_IOPAD(0x244, PIN_OUTPUT, 2) /* (C17) MMC1_SDWP.TIMER_IO7 */
 		>;
 	};
 
-- 
2.37.1



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