linux-kernel - [PATCH v2] leds: group-multicolor: Add support for initial value.

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Message-ID: <20251124210521.2064660-1-martijn.de.gouw@prodrive-technologies.com>
Date: Mon, 24 Nov 2025 22:05:20 +0100
From: Martijn de Gouw <martijn.de.gouw@...drive-technologies.com>
To: Lee Jones <lee@...nel.org>, Pavel Machek <pavel@...nel.org>
CC: Martijn de Gouw <martijn.de.gouw@...drive-technologies.com>,
	<linux-leds@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: [PATCH v2] leds: group-multicolor: Add support for initial value.

When the driver is loaded, it turned off all LEDs in the group. This
patch changes the driver to take over existing LED states and set
the brighness and intensity in the group accordingly.

Signed-off-by: Martijn de Gouw <martijn.de.gouw@...drive-technologies.com>
---
 drivers/leds/rgb/leds-group-multicolor.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/leds/rgb/leds-group-multicolor.c b/drivers/leds/rgb/leds-group-multicolor.c
index 548c7dd63ba1e..a12720d73f188 100644
--- a/drivers/leds/rgb/leds-group-multicolor.c
+++ b/drivers/leds/rgb/leds-group-multicolor.c
@@ -69,6 +69,7 @@ static int leds_gmc_probe(struct platform_device *pdev)
 	struct mc_subled *subled;
 	struct leds_multicolor *priv;
 	unsigned int max_brightness = 0;
+	unsigned int default_brightness = 0;
 	int i, ret, count = 0, common_flags = 0;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -96,6 +97,13 @@ static int leds_gmc_probe(struct platform_device *pdev)
 
 		max_brightness = max(max_brightness, led_cdev->max_brightness);
 
+		/*
+		 * If any LED is on, set brightness to the max brightness.
+		 * The actual brightness of the LED is set as intensity value.
+		 */
+		if (led_cdev->brightness)
+			default_brightness = max_brightness;
+
 		count++;
 	}
 
@@ -109,14 +117,16 @@ static int leds_gmc_probe(struct platform_device *pdev)
 
 		subled[i].color_index = led_cdev->color;
 
-		/* Configure the LED intensity to its maximum */
-		subled[i].intensity = max_brightness;
+		/* Configure the LED intensity to its current brightness */
+		subled[i].intensity = DIV_ROUND_CLOSEST(led_cdev->brightness * max_brightness,
+							led_cdev->max_brightness);
 	}
 
 	/* Initialise the multicolor's LED class device */
 	cdev = &priv->mc_cdev.led_cdev;
 	cdev->brightness_set_blocking = leds_gmc_set;
 	cdev->max_brightness = max_brightness;
+	cdev->brightness = default_brightness;
 	cdev->color = LED_COLOR_ID_MULTI;
 	priv->mc_cdev.num_colors = count;
 
-- 
2.39.2