reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git/commit/?id=678bae2eaa812662929a83b3de399645e9de93ad
        git remote add brgl https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
        git fetch --no-tags brgl gpio/for-next
        git checkout 678bae2eaa812662929a83b3de399645e9de93ad
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um olddefconfig
        make W=1 O=build_dir ARCH=um SHELL=/bin/bash drivers/nfc/s3fwrn5/