I2C cmake errors (v1.13 and v1.12) ? #nrf52832


Hi All,

I'm trying to build the I2C sample programs or those that use I2C for the nrf52, but keep seeing the following error.
Is there something I need to do to enable using I2C from the chip? I presume I'm missing something straightforward here. 
I tried both the current_sensing and the i2c_fujitsu_fram sample programs. 

~/src/zephyr/samples/drivers/current_sensing/build 15:36:16>cmake -DBOARD=nrf52_pca10040 ..
-- Found PythonInterp: /usr/bin/python3 (found suitable version "3.6.5", minimum required is "3.4") 
-- Selected BOARD nrf52_pca10040
Zephyr version: 1.13.0
Parsing Kconfig tree in /home/gps/src/zephyr/Kconfig
Loading /home/gps/src/zephyr/boards/arm/nrf52_pca10040/nrf52_pca10040_defconfig as base
Merging /home/gps/src/zephyr/samples/drivers/current_sensing/prj.conf
warning: tag 'zephyr-v1.13.0' is really 'v1.13.0' here
-- Generating zephyr/include/generated/generated_dts_board.h
-- Cache files will be written to: /home/gps/.cache/zephyr
-- The C compiler identification is GNU 6.2.0
-- The CXX compiler identification is GNU 6.2.0
-- The ASM compiler identification is GNU
-- Found assembler: /home/gps/src/zephyr-sdk/sysroots/x86_64-pokysdk-linux/usr/bin/arm-zephyr-eabi/arm-zephyr-eabi-gcc
-- Performing Test toolchain_is_ok
-- Performing Test toolchain_is_ok - Success
CMake Error at ../../../CMakeLists.txt:527 (message):
  The Zephyr library 'drivers__i2c' was created without source files.  Empty
  (non-imported) libraries are not supported.  Either make sure that the
  library has the sources it should have, or make sure it is not created when
  it has no source files.

Any help would be appreciated. 



Never mind.. found this fantastic youtube video in the `Enable SPI driver` thread that helped solve the issue: https://youtu.be/vioi4OsmB_U