I am using ubuntu:
Operating System: Ubuntu 18.04.5 LTS
Kernel: Linux 4.19.193
I am trying to use usb-lan adapter lan7800.
firefly@firefly:~/Downloads$ zcat /proc/config.gz | grep LAN78
# CONFIG_USB_LAN78XX is not set
You need to configure the kernel similar to the following, and then repackage the boot.img.
cd SDK/kernel
make ARCH=arm64 firefly_linux_defconfig
make ARCH=arm64 menuconfig
make ARCH=arm64 savedefconfig
mv defconfig arch/arm64/configs/firefly_linux_defconfig