linux-kernel - [PATCH V4 0/2] leds: pwm: Add optional GPIO enable pin support

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Message-ID: <20250703093430.229959-1-Qing-wu.Li@leica-geosystems.com.cn>
Date: Thu,  3 Jul 2025 17:34:28 +0800
From: LI Qingwu <Qing-wu.Li@...ca-geosystems.com.cn>
To: lee@...nel.org,
	pavel@...nel.org,
	robh@...nel.org,
	krzk+dt@...nel.org,
	conor+dt@...nel.org,
	linux-leds@...r.kernel.org,
	devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Qing-wu.Li@...ca-geosystems.com.cn
Cc: bsp-development.geo@...ca-geosystems.com
Subject: [PATCH V4 0/2] leds: pwm: Add optional GPIO enable pin support

Add support for an optional GPIO enable pin to the PWM LED driver.
Some LED controllers require an additional enable GPIO to be enabled
on the device before PWM control can take effect.

Testing:
- Tested on i.MX8MP EVK board with TPS92380 LED backlight driver
- Verified GPIO enable/disable functionality works correctly
- Confirmed both GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW polarities
  work properly


Device tree configuration used for testing:

	backlight_keypad: backlight-keypad {
		compatible = "pwm-leds";

		led {
			color = <LED_COLOR_ID_WHITE>;
			enable-gpios = <&pca6416 11 GPIO_ACTIVE_HIGH>;
			function = LED_FUNCTION_KBD_BACKLIGHT;
			max-brightness = <100>;
			pwms = <&pwm3 0 2500 0>;
		};
	};

Changes in V4:
- Reword commit message to specify the LED driver chip TPS92380
- Add tested device tree configuration to cover letter

Changes in V3:
- fix make dt_binding_check failed on check leds-pwm.yaml




LI Qingwu (2):
  dt-bindings: leds: pwm: add enable-gpios property
  leds: pwm: Add optional GPIO enable pin support

 .../devicetree/bindings/leds/leds-pwm.yaml    |  7 ++++++
 drivers/leds/leds-pwm.c                       | 22 +++++++++++++++++++
 2 files changed, 29 insertions(+)

-- 
2.43.0