Camera RTC debug tracing on R32.3.1

The instructions for debugging in camera development from (https://elinux.org/Jetson_TX2_Camera_BringUp) have a section on enabling the tracing.
This is on L4T R32.3.1:
The command
echo 2 > /sys/kernel/debug/camrtc/log-level
fails.
I believe this is why I get much lower resolution of the tracing. It seems that the tegra186-camera-ivc-protocol-debug driver is not loaded. What could be the cause of this, and how can I make it load?

hello jschwendner,

may I know which Jetson platform you’re working with?
thanks

Just realized this feature might only be available on TX2. We have both platforms in production, but I’ve made the test on a TX1.