title: makefile - what to do with the kconfig file
body: <p>I stumbled over this <a href="http://www.linuxtv.org/wiki/index.php/Easycap#USBTV007_EasyCAP" rel="nofollow">site</a> about USB video grabber under Linux, I'm trying to compile the code found <a href="https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/media/usb/usbtv" rel="nofollow">here</a>. I have read about makefiles but this one confuses me, cause it's so short:</p>
  
  <pre><code>usbtv-y := usbtv-core.o \
      usbtv-video.o
  
  obj-$(CONFIG_VIDEO_USBTV) += usbtv.o
  </code></pre>
  
  <p>I wanted to write now my own makefile. What I want to know now is, what the <code>Kconfig</code> file is for and how to use it. I have a hard time finding more information about how to use it, just some stuff regarding KDE which is not what I want. Can someone enlighten me please? I think it's important, cause in the description (on the first site I linked) it says under how to make it work</p>
  
  <blockquote>
    <p>Linux kernel driver, enable CONFIG_VIDEO_USBTV</p>
  </blockquote>
  
  <p>Here's the Kconfig file:</p>
  
  <pre><code>config VIDEO_USBTV
          tristate "USBTV007 video capture support"
          depends on VIDEO_V4L2
          select VIDEOBUF2_VMALLOC
  
          ---help---
            This is a video4linux2 driver for USBTV007 based video capture devices.
  
            To compile this driver as a module, choose M here: the
            module will be called usbtv
  </code></pre>
  
  <p>Also, what is meant in the Kconfig file with "choose M here"? Where? How? When?</p>