How to use hal external module with Zephyr?

[mourad96]

I'm trying to create a HAL library to use it with zephyr application

From what I have read I need to create another module .

I can't figure out how to set up the module and how to compile it.

for the moment I have only 1 module to add with the following files hal_flash.c and hal_flash.h

How can I add cmake files kconfig files to make it work with zephyr application

note: app on nRF9160

What I have tried so far:

added module to the west.yml file

and this is the structure of the module:

module_repo/CMakeLists contains:

module_repo/prj.conf contains
CONFIG_FOO=y

in module_repo/drivers/foo/CMakeLists.txt :

in module_repo/drivers/foo/Kconfig :

and module_repo/zephyr/module.yml :

and when I test my application (with CONF_FOO=y in prj.conf of the app) I got this error
src/main.c:9: undefined reference to hal_flash_flush

[mourad96]

I found the problem:

I should change module_repo/CMakeLists to:
add_subdirectory(drivers/foo)