Including complete library (set of files) at once in cmakelists.txt (vscode)

[ETX]

I'm trying to get the u8g2 library for OLED-displays to work, but I can't get it included properly.
When I'm adding source and lib files (e.g. test_io.c and test_io.h) to the appropriate core folders,
I usually do include the paths for every *.c file separately in the makelists.txt like shown here, which works fine:

# Add sources to executable
target_sources(${CMAKE_PROJECT_NAME} PRIVATE
    # Add user sources here
    ../../Core/Src/test_io.c    

)

But what is the right way to go with vscode, when adding a complete library, like u8g2 with a dozen files?
I found an example, where the complete u8g2 library folder (../csrc) is copied into the driver path and, for MXcube,
included via compiler setting.

Like this, in vscode I also copied the complete library to the drivers folder and added the include path to makelists.txt like this:

# Add include paths
target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
    # Add user defined include paths
    ../../Drivers/csrc/  # No error while compiling, but doesn't seem to work
    
)

# Add linked libraries
target_link_libraries(${CMAKE_PROJECT_NAME}
    stm32cubemx
    # ../../Drivers/csrc/   # Failed with error while compiling

    # Add user defined libraries
)

But that doesn't work at all.
I got errors on #include "u8g2.h" in my main.c file and vscode doesn't seem to recognize any of the files included in the ../../Drivers/csrc/ path.

Any ideas how to do this the right way?

EDIT:

I figured out something more:
Using STM32 extension in vscode, there are TWO CMakeLists.txt files.
First one created by CubeMX, created new every time you update your project (path: ${PROJ_PATH}/cmake/stm32cubemx/) and
the second created only once by CubeMX when starting a new project, to be edited by the user (path: ${PROJ_PATH}).

Adding the include path to the first CMakeLists.txt file like this works fine:

target_include_directories(stm32cubemx INTERFACE
../../Core/Inc
../../Drivers/STM32G0xx_HAL_Driver/Inc
../../Drivers/STM32G0xx_HAL_Driver/Inc/Legacy
../../Drivers/CMSIS/Device/ST/STM32G0xx/Include
../../Drivers/CMSIS/Include
../../Drivers/csrc # works fine

)

But the problem is, it gets deleted every time you update with CubeMX.

Adding the include path to the second CMakeLists.txt file like this doesn't work at all:

target_include_directories(stm32cubemx INTERFACE
../../Drivers/csrc # doesn't work
)

OR

target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
# Add user defined include paths
../../Drivers/csrc # doesn't work either
)

Now, to update my question:
How to get included directories in the second, user editable, CMakeLists.txt file work correctly?

[ETX · Accepted solution]

OK, I figured it out myself.

The correct syntax for including a directory is:

# Add include paths
target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
    # Add user defined include paths
   ${CMAKE_SOURCE_DIR}/Drivers/csrc
)