[ECOS] inital patch for PID driver

[Dave Airlie]

Hi,
	Please find attached a cleanup patch for the pid driver in CVS, 

it does two things, cleans up #defines as was done for AEB driver before,
fixes a bug I think exists,

if the UART receives a byte and raises the interrupt line but the CPU
has interrupts disabled (for some reason), and the UART receives a second
byte (which it sticks in the FIFO), now the CPU comes along and see the
interrupt and only takes one byte from the FIFO, does the UART keep the
line raised until the FIFO has emptied?? if not then we are always a byte
behind, so I've stuck in a while loop to read all the bytes from the
receiver FIFO, 

I'm not sure if the second piece is needed but it helps some code I'm
working on here run better...

Dave.


-- 
      David Airlie, Software Engineer, Parthus Technologies plc.,
       Mary Rosse Centre, National Tech Park, Limerick, Ireland.
   t: +353-61-508116 / f: +353-61-508101 / David.Airlie@parthus.com