Introduce a new configuration parameter in Linux Kernel make menuconfig

Question

I added a feature in Linux kernel which I switch on/off using pre-processor macros. I now want these macros to be available in make menuconfig as configuration parameters. I tried to add them in the default configuration file but the make process does not recognize its format (it gives error). Is there a special way to add preprocessor macros to the configuration file (for e.g. preceding the paramater name with a CONFIG_*)?

I am not too experienced with the configuration process. Any help will be appreciated.

Thanks.

Answer 1

menuconfig configuration is done by 2 files that exists in almost any directory in the kernel code. Kconfig and Makefile
To add a new configuration you need to choose the directory based on the settings you want to add and edit the 2 files: on Kconfig you need to add:

config MY_SETTING
    bool “This is the menuconfig label”
    default y
    help
       help for your new option 

Edit the Makefile in the same directory and add:

obj-$(CONFIG_MY_SETTING)       += yournewcode.o

The constant CONFIG_MY_SETTING is defined by the kernel and contains 'y' if the user select it from the menuconfig you can also change 'bool' to 'tristate' if you want to add a file as a loadable module and the above constant contains 'm' if user choose to compile it as a module

if you don't need any file associated with the constant just declare it in Kconfig file