linux-kernel - [PATCH v2 2/2] leds: pwm: Add optional DT property default-brightness

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Message-ID: <20241101154844.1175860-3-gnstark@salutedevices.com>
Date: Fri, 1 Nov 2024 18:48:44 +0300
From: George Stark <gnstark@...utedevices.com>
To: <pavel@....cz>, <lee@...nel.org>, <robh@...nel.org>, <krzk+dt@...nel.org>,
	<conor+dt@...nel.org>
CC: <linux-leds@...r.kernel.org>, <devicetree@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>, <kernel@...utedevices.com>, George Stark
	<gnstark@...utedevices.com>
Subject: [PATCH v2 2/2] leds: pwm: Add optional DT property default-brightness

When probing if default LED state is on then default brightness will be
applied instead of max brightness.

Signed-off-by: George Stark <gnstark@...utedevices.com>
---
 drivers/leds/leds-pwm.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c
index 7961dca0db2f..7636ee178c39 100644
--- a/drivers/leds/leds-pwm.c
+++ b/drivers/leds/leds-pwm.c
@@ -63,6 +63,20 @@ static int led_pwm_set(struct led_classdev *led_cdev,
 	return pwm_apply_might_sleep(led_dat->pwm, &led_dat->pwmstate);
 }
 
+static int led_pwm_default_brightness_get(struct fwnode_handle *fwnode,
+					  int max_brightness)
+{
+	unsigned int default_brightness;
+	int ret;
+
+	ret = fwnode_property_read_u32(fwnode, "default-brightness",
+				       &default_brightness);
+	if (ret < 0 || default_brightness > max_brightness)
+		default_brightness = max_brightness;
+
+	return default_brightness;
+}
+
 __attribute__((nonnull))
 static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
 		       struct led_pwm *led, struct fwnode_handle *fwnode)
@@ -104,7 +118,8 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
 	/* set brightness */
 	switch (led->default_state) {
 	case LEDS_DEFSTATE_ON:
-		led_data->cdev.brightness = led->max_brightness;
+		led_data->cdev.brightness =
+			led_pwm_default_brightness_get(fwnode, led->max_brightness);
 		break;
 	case LEDS_DEFSTATE_KEEP:
 		{
-- 
2.25.1