CM3588 NAS Kit - I2C via GPIO

[ppsx]

Hi.

I'm using official OpenMediaVault software with NAS kit which has been installed on eMMC.

According to the doc (wiki page) there is one I2C located on GPIO header. In the CM3588 NAS SDK Schematic pdf I've found that SDA=Pin3 and SCL=Pin5. I'd like to use it for OLED screen. I do have some experience with the very same OLED screen connected to ESP32C3 and RP2040 so I'm sure it's working fine.

However I believe that I2C on the CM3588 is not enabled by default as I don't see any changes when using sudo i2cdetect -l with OLED screen connected to and disconnected from the GPIO header.

I can't find anything similar to raspi-config (RaspberryPi) nor to orangepi-config utilities. Does one exist for CM3588 NAS Kit?

How can I enable I2C then? /boot/ folder does not contain any kind of config.txt file but two subdirectories only: firmware, which contains only binary blobs, and grub.

I will be grateful for any help.

[yaazzz]

I did not find a solution either. Anyhelp will be wonderfull!

[NadiaEira]

Still need help!

[leoenda2006]

Step 1 — Check if I2C buses already exist but aren't detected:
bashls /dev/i2c-*
Sometimes the bus exists but i2cdetect -l doesn't show it cleanly.
Step 2 — Check your kernel for I2C support:
bashdmesg | grep i2c
This tells you whether I2C drivers loaded at all.
Step 3 — Find your device tree source:

Since there's no config.txt, you'll need to modify or overlay the .dtb file. Look in /boot/firmware/ for a .dtb file matching your board — something like rk3588-cm3588-nas.dtb.
Step 4 — Enable I2C via overlay:

Some OMV/Rockchip builds support drop-in .dtbo overlay files. Check if /boot/firmware/overlays/ exists — if it does, there may already be an i2c overlay ready to enable.