compile device driver

How can I compile a device driver for the mini2440 without having to 
modified or recompile the kernel? whats the command?

i need that to :(

Read kernel's "Documentation/kbuild/modules.txt"

that didnt work according to that module.txt and to compile a hello.c
module this is how is set

(hello.c)
#include <linux/kernel.h>
#include <linux/module.h>


static int __init mini2440_hello_module_init(void)
{
    printk("Hello, Mini2440 module is installed !\n");
    return 0;
}

static void __exit mini2440_hello_module_cleanup(void)
{
    printk("Good-bye, Mini2440 module was removed!\n");
}

module_init(mini2440_hello_module_init);
module_exit(mini2440_hello_module_cleanup);
MODULE_LICENSE("GPL");
=======================================================================
(Makefile)
obj­m  := hello.o
========================================================================

and command line:

andre@mini2440:~/driverdev$ make -C /home/andre/mini2440/linux-2.6.32.2/
M=`pwd`

I'm using this Makefile content instead:

---------------------------
ifeq ($(KERNEL_DIR),)

all:
        @echo "please export KERNEL_DIR"

clean:
        rm -rf *.o *.ko *.kmod *.mod.c .*.cmd .*.o.d Module.symvers
.tmp_versions modules.order

else

obj-m   := hello.o

modules modules_install clean:
        $(MAKE) -C $(KERNEL_DIR) M=$(CURDIR) V=$(V) $@

endif
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