How to cross compile module for Yocto distro

Hi, I need help for building a kernel module (for the PL2303 USB-serial converter device) for a custom Yocto distribution.
What I've tried to do has been to compile the pl2303.ko binary file using bitbake and it seems to work, but when I try to load it inside the running OS (issuing the insmod pl2303.ko command) it gives the following error: insmod: ERROR: could not insert module ko/pl2303.ko: Invalid parameters; then I issue the dmesg command and this is the output:
[17585.849506] pl2303: disagrees about version of symbol dev_err
[17585.853980] pl2303: Unknown symbol dev_err (err -22)

The kernel is (uname -a output):
Linux seco-sbc-a62 4.14.78+g15a48d6 #1 SMP PREEMPT Thu Nov 21 08:44:23 UTC 2019 armv7l armv7l armv7l GNU/Linux

I've also tried to compile the sources (pl2303.c/h) directly on the board but it gives this error:
make -C /lib/modules/4.14.78+g15a48d6/build M=/home/root/pl2303 module modules
make[1]: Entering directory '/usr/src/linux-4.14.78'
make[1]: *** No rule to make target 'module'. Stop.
make[1]: Leaving directory '/usr/src/linux-4.14.78'
make: *** [Makefile:10: all] Error 2

I've downloaded and unzipped this file: linux-4.14.78.tar.gz in /usr/src/linux-4.14.78