Issue with ROCK PI 4 C PLUS I2C bus

#1

Hi,

I am having some issues getting the i2c to work on a RockPi 4 C+, since I am not able to scan correctly on the i2c busses using mraa-i2c nor i2c-tools.
Currently I am running the latest release of rock-pi-4 debian bullseye kde (55b), I set up the apt packges for the distro bullseye-stable and successfully installed rockchip-overlay, rockpi4-dtbo and libmraa.
I edited the /boot/hw_intfc.conf file to enbale i2cs, setting intfc:i2c2,6,7=on and rebooted the system.
Nevertheless, with a i2c slave powered and connected on pins I2C7_SDA and I2C7_SCL on the pins 3 and 5 of the connector, I am not able to see the address of the slave when I use mraa-i2c detect 0, which returns an empty string.

I have noticed that I am also not able to locate the package rockpi4c-rk-u-boot-latest when trying to install it. but u-boot-latest seems to be at the latest version.

Do you have any additional idea about what the problem might be?

Thanks, let me know if you need additional dettails

#3

Yep, I tried also with both i2c0 and i2c9, but their pins are not exposed.

I found a solution configuring the i2c7 and i2c2 using the rsetup script (https://wiki.radxa.com/Rockpi4/hardware/devtree_overlays_linux5.10#i2c7) to enable the overlay for i2c. After enabling them with the script they should be visible when listing the enabled i2c devices, as happens by default with i2c0 and i2c9.

Please note that this solution using rsetup seems to be stable only if I download a new image of radxa ubuntu11 and use directly the rsetup script without installing their packages.
If I setup the overlays with rsetup after installing their packages (as suggested in the installation doc) just touching the board is enought to make the i2c transition to fail or not detecting any device on the bus.

Let me know if it works for you.

#4

Had you solved this issue? We have the same concern in here. Please let me know on how you solved it. Thank you.