Building libraries and binaries using Kbuild in a different folder

Hi,

I have a kernel module which is built using Kbuild. However, when I
try to compile it via:

make -C /lib/modules/`uname -r`/build M=$PWD

The modules are built in the pwd. Is there a way to get all the
generated files moved to a different location, so that my checkout
area is clean ?

Also, using my Kbuild file, I build more than one .ko files. Is there
a way to build only one target ? i.e., If my .ko generates a.ko ,b.ko
and c.ko, Is there a way to build b.ko alone if I want ?

Thanks.

-- 
Sankar P
http://psankar.blogspot.com