title: What is the difference between DMA-Engine and DMA-Controller?
body: <ol>
  <li><p>As mentioned above, what is the difference between a dma engine and a dma-controller (on focus on linux)? </p></li>
  <li><p>When does the linux dma engine come into place? Is this a special device or always part of all periphery devices, which support dma?</p></li>
  <li><p>When browsing the linux source, I found the driver ste_dma40.c. How does any driver uses this engine? </p></li>
  </ol>