@nkos Our driver code is developed based on Radxa's BSP, and the BSP development documentation can be found at the following URL:
https://docs.radxa.com/en/zero/zero3/low-level-dev/kernel
To address the issue you raised, we attempted to set up a Yocto development environment for the Radxa ZERO 3. Unfortunately, we were unsuccessful in this endeavor.
Later, we noticed Radxa's documentation regarding building Linux images with Yocto:
https://github.com/radxa/yocto-manifests
In the "List of Radxa Boards supported" section, the Radxa ZERO 3 is not listed among the supported development boards.
Therefore, we do not recommend using Yocto to build a Linux image for the Radxa ZERO 3.