I just committed some minor changes to the nextdma driver interface.  I
eliminated the "nd_chaining_flag" and unified the interface for
chaining and non-chaining dma sequences.  The driver now relies on the
"nd_continue_cb" callback function returning NULL to decide when to shut
down DMA, even if that happens after only one dma segment is loaded.

In addition, I made the driver restart dma automatically if it shuts
down unexpectedly.

Darrin