[Buildroot] In Buildroot, how to compile kernel modules

[Arnout Vandecappelle]

On 26/02/14 08:31, Frank Ihle wrote:
> Right setting kernel dependencies makes sense, but I'm not so sure about
> the process: when I have the following makefile
> 
> obj-m += /<path-to-module>/measurement_gpio.o

 The obj-m should not contain a path.

> KDIR := /<BR-path>/output/build/linux-2.6.39/
> PWD := $(shell pwd)
> default:
>     $(MAKE) ARCH=arm
> CROSS_COMPILE=/<BR-path>/output/host/opt/ext-toolchain/bin/arm-none-linux-gnueabi-
> -C modules
> 
> where is then the generated .ko file and how can I make sure that in this
> build process the .ko file will be moved to a certain place ?

 The modules_install target of the kernel will do that:

define ON2_8170_MODULES_INSTALL_TARGET_CMDS
$(MAKE) -C $(LINUX_DIR) $(LINUX_MAKE_FLAGS) M=$(@D) \
        modules_install
endef


 If you want to support the same from your own makefile, you should add
something like:

make -C $(KDIR) M=`pwd` INSTALL_MOD_PATH=<...>/output/target \
	modules_install


 By the way, please don't top-post, and strip the irrelevant parts from
the quoted text.

 Regards,
 Arnout

> 
> Kind Regards
> 
> Frank
> 

[snip]

-- 
Arnout Vandecappelle                          arnout at mind be
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