Blue LED off

[were55]

Hi,

I would like to turn off the blue LED that is blinking all the time, any idea how to deal it?

thanks

[odroid]

LED trigger node doesn't exist. We will look into the kernel option.

[were55]

Thanks Odroid, let me know to test it.

[odroid]

The blue LED trigger node exists.

Turn off

Code: Select all

su -
echo none > /sys/class/leds/blue\:heartbeat/trigger

Turn on

Code: Select all

su -
echo deafult-on > /sys/class/leds/blue\:heartbeat/trigger

Hearbeat (original state)

Code: Select all

su -
echo heartbeat > /sys/class/leds/blue\:heartbeat/trigger

There are much more triggers. But some of them may not work.

Code: Select all

cat /sys/class/leds/blue\:heartbeat/trigger                                                                                                                                                                                                                                                                                                                     
none rc-feedback nand-disk timer oneshot [heartbeat] backlight gpio cpu0 cpu1 cpu2 cpu3 default-on transient flash torch sd emmc battery-charging-or-full battery-charging battery-full battery-charging-blink-full-solid ac-online   

[nstevens]

I have a C2 and notice that one of the triggers for the blue LED is GPIO.
Anyone know which GPIO #
I know on a Raspberry Pi 2 it is GPIO 47 but that didn't work.

[were55]

@odroid: Thanks qorks fine off and hearbeat, not always on, but now my wife is happy

[odroid]

@were55
Good to know your wife is happy now.
I agree the blue LED is too much bright in night time.

@nstevens
As far as I know the GPIO(PIOAO-BIT13) pin for the blue LED was not exported to the sysfs.
Check LED driver source code in the Kernel if possible.

[toyanucci]

The blue LED trigger node exists.

Turn off

Code: Select all

su -
echo none > /sys/class/leds/blue\:heartbeat/trigger

Turn on

Code: Select all

su -
echo deafult-on > /sys/class/leds/blue\:heartbeat/trigger

Hearbeat (original state)

Code: Select all

su -
echo heartbeat > /sys/class/leds/blue\:heartbeat/trigger

There are much more triggers. But some of them may not work.

Code: Select all

cat /sys/class/leds/blue\:heartbeat/trigger                                                                                                                                                                                                                                                                                                                     
none rc-feedback nand-disk timer oneshot [heartbeat] backlight gpio cpu0 cpu1 cpu2 cpu3 default-on transient flash torch sd emmc battery-charging-or-full battery-charging battery-full battery-charging-blink-full-solid ac-online   

I'm running libreelec and these commands work but are reset upon reboot. How do I make them stick?

[were55]

@toyanucci ,you can add the lines in crontab ,it works fine in libreelec.

[redbird]

In Android Lollipop on the C2 I was able to add the following as the last lines of the "on boot" section int /system/init.odroidc2.rc:

Code: Select all

    #Turn off blue led heart beat
    write /sys/class/leds/blue\:heartbeat/trigger none

...but when I try in Ubuntu I get the following:

Code: Select all

odroid@odroid64:~$ sudo echo none >/sys/class/leds/blue\:heartbeat/trigger
-bash: /sys/class/leds/blue:heartbeat/trigger: Permission denied
odroid@odroid64:~$

What am I missing?

[odroid]

Run "sudo su" first and type "echo ~~~" command.

[redbird]

Thanks very much -- that pointed me in the right direction. The following in /etc/rc.local did the trick:

Code: Select all

echo none >/sys/class/leds/blue\:heartbeat/trigger

Now, I'll go for the gold.

1) Any way to turn off the red power led?
2) Any way to turn off the green/yellow ethernet light?

No other entries in the /sys/class/leds directory. Would it be possible with a custom kernel config/build? Any ideas or pointers would be appreciated.

Stealth mode could likely save my marriage!

[endecotp]

I thought that ethtool could perhaps change the ethernet led behaviour, but perhaps not.
Some googling finds a very recent proposed kernel patch related to this; its existence suggests that it was not previously possible in software: http://www.spinics.net/lists/netdev/msg380767.html

Black PVC tape or similar might work!

[endecotp]

OK, the phy chip definitely has a register that can turn off the LEDs. It's the "led control register" or LEDCR at mii address 0x18. I'm not sure how to write to it. There is an ioctl, SIOCMIIREG, that would probably work.

[jeff]

Not sure where my C2 is right now, but at least on the XU4 you can turn the LED trigger to "none" (as described above) and set the blue LED brightness 0-255 with /sys/class/leds/blue\:heartbeat/brightness

[Skinah]

I know this thread is old but after a lot of searching I got it to finally work across reboots in the following way. The reason it was not working is that newer Ubuntu versions need rc.local to be executable to auto run on startup. I found the default file needed this from odroids ubuntu minimal image version 1804 LTS.

This makes it flash on sd access.

```
sudo sed -i '1 i #!/bin/sh' /etc/rc.local
sudo sed -i -e 's/exit 0/#exit 0/g' /etc/rc.local
sudo sh -ce "echo 'echo sd >/sys/class/leds/blue\:heartbeat/trigger' >> /etc/rc.local"
sudo sh -ce "echo 'exit 0' >> /etc/rc.local"
sudo chmod +x /etc/rc.local
```