User LEDs control

Joshua Park

unread,

Oct 11, 2020, 3:01:06 PM10/11/20

to BeagleBoard

Hi all,

I am trying to change the user LEDs but I am unable to make permanent changes to the files in /sys/devices/platform/leds/leds. Can someone help me out?

Thanks in advance.

Joshua Park

unread,

Oct 11, 2020, 3:34:45 PM10/11/20

to BeagleBoard

Also, I figure that I process is controlling the blinking of user LED 1 since that is the only one I cannot change. Can anyone tell me what this process is and if I can stop it from controlling LED 1?

jonnymo

unread,

Oct 11, 2020, 5:54:41 PM10/11/20

to Beagle Board

I'm not sure what board you have or what kernel you are running, however on a Beaglebone Black running a 4.19 kernel, the LED settings are located in the bone-common.dtsi file:

Note: From the BBB schematic, led1 is connected to the Ethernet port, so perhaps you are trying to control usr0 LED.

Ex:

/opt/source/dtb-4.19-ti/src/arm/am335x-bone-common.dtsi

leds {
pinctrl-names = "default";
pinctrl-0 = <&user_leds_s0>;

compatible = "gpio-leds";

led2 {
label = "beaglebone:green:usr0";
gpios = <&gpio1 21 GPIO_ACTIVE_HIGH>;
linux,default-trigger = "heartbeat";
default-state = "off";
};

led3 {
label = "beaglebone:green:usr1";
gpios = <&gpio1 22 GPIO_ACTIVE_HIGH>;
linux,default-trigger = "mmc0";
default-state = "off";
};

led4 {
label = "beaglebone:green:usr2";
gpios = <&gpio1 23 GPIO_ACTIVE_HIGH>;
linux,default-trigger = "cpu0";
default-state = "off";
};

led5 {
label = "beaglebone:green:usr3";
gpios = <&gpio1 24 GPIO_ACTIVE_HIGH>;
linux,default-trigger = "mmc1";
default-state = "off";
};
};

Cheers,

Jon

--
For more options, visit http://beagleboard.org/discuss
---
You received this message because you are subscribed to the Google Groups "BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/acfff9b2-a632-47a7-a4f0-29991e4475c5n%40googlegroups.com.

Mark A. Yoder

unread,

Oct 12, 2020, 10:44:51 AM10/12/20

to BeagleBoard

This may be off topic, but I have some notes on how to switch a GPIO pin to be an LED.