Rpi4 eth_led0 set to 4, amber light stays on

[LotusOttawa]

Latest Rasbian on Pi4, eth_led0 setting to 4 does not function as documented. Amber LED stays on.

[JamesH65]

Can you point to the docs that are wrong?

[LotusOttawa]

https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README line 126

[JamesH65]

Just to confirm your changes are actually taking affect, do the other values do what you expect?

Using this is config.txt:

dtparam=act_led_trigger=heartbeat
dtparam=pwr_led_trigger=mmc0
dtparam=eth_led0=4
dtparam=eth_led1=4

The eth leds are both active (green blinking, amber constant), the others 2 are behaving as expected from the config.

[LotusOttawa]

Is there a logfile to know if the changes take effect?

act_led_trigger=cpu works as it should but pwr_led_trigger=cpu keeps the LED on constantly

[pelwell]

This issue is about the eth_led parameters - please create a new issue for any other LED parameter problems (they are likely to have a different cause).

sudo vcdbg log msg displays the logging output from the firmware, which might give provide a clue in the event of an error.

002795.506: dtparam: act_led_trigger=heartbeat
002844.037: dtparam: pwr_led_trigger=mmc0
002892.686: dtparam: eth_led0=4
002905.456: Unknown dtparam 'eth_led0' - ignored
002905.548: dtparam: eth_led1=4
002918.307: Unknown dtparam 'eth_led1' - ignored

[pelwell]

These parameters were only added in kernel 4.19.83 - if your kernel is older then you will have to update (or wait for the update to become available - I'm not sure which is the latest Raspbian kernel).

Confirmed for me. Current kernel is version 4.19.75, upgrade to a version after .83 switched the lights off.

[LotusOttawa]

I've now been able to upgrade to 4.19.93-v7l+

The eth_led0, eth_led1 Pi4 settings don't work as documented.

[pelwell]

Show us your config.txt file.

[LotusOttawa]

dtparam=eth_led0=4
dtparam=eth_led1=9

The comments are also hard to decipher (e.g. what's the difference between 0, 2, and 7?):

Pi4

                            0=Speed/Activity (default)       1=Speed
                            2=Speed/Flash activity   3=FDX
                            4=Off                    5=On
                            6=Alt                    7=Speed/Flash
                            8=Link                   9=Activity

[pelwell]

With your settings the test Pi4 on my desk has the green LED off and the orange LED flashing with activity. What do you see?

The comments are also hard to decipher (e.g. what's the difference between 0, 2, and 7?):

My understanding is:

• Speed means on for a fast link (probably 1Gb/s), otherwise off.
• Activity inverts the current state for a short period for every packet, so more traffic means more flicker.
• Flash activity is like Activity but without the proportionality - the pulses (which could be on or off depending on the other part of the mode) are a fixed width and the gaps are of (the same) minimum width, such that you see a clear flash pattern if there is activity and a steady state if not.

It looks like 2 is mislabelled and should just say Flash activity.

[JamesH65]

The data we had on this was extremely sketchy - seems very likely I have got some terminology wrong in the docs.