How to change LED trigger?

Question

I have register in BSP's the LED:

static struct gpio_led ic_leds[] = {
        {
                .name                   = "led1:green",
                .gpio                   = USER_LED,
                .default_trigger        = "heartbeat",
                .active_low             = 1,
        },
};

static struct gpio_led_platform_data ic_led_info = {
        .num_leds       = ARRAY_SIZE(ic_leds),
        .leds           = ic_leds,
};

static struct platform_device ic_leds_device = {
        .name   = "leds-gpio",
        .id     = -1,
        .dev    = {
                .platform_data = &ic_led_info,
        },
};

static void __init ic_add_device_leds(void)
{
        platform_device_register(&ic_leds_device);
}

How can I change the trigger in run time? I know that it's possible with sysfs, but maybe exist another way?

score 5 · Answer 1 · edited Mar 16 '21 at 06:14

echo "thetriggeryouwant" > /sys/class/leds/someled/trigger

where thetriggeryouwant is for example phy0rx and someled is the name of the led you want to change the trigger for.

To get all available triggers for that led, you can cat the file:

cat /sys/class/leds/someled/trigger

gives for example:

[none] timer oneshot mtd nand-disk heartbeat backlight gpio cpu cpu0 cpu1 activity default-on 2188000.ethernet-2:00:link 2188000.ethernet-2:00:100Mbps 2188000.ethernet-2:00:10Mbps

where the item in brackets ([none]) denotes the current trigger.

How to change LED trigger?

1 Answers1