There is no such a thing like a ide-clean-15. Never was.  But here comes
what has been done in ide-clean-16:

- Apply a patch for the initialization of the second PIIX channel.
   Found by Daniel Quinlan <quinlan@transmeta.com>

- Apply a patch for the DMA initialization of the serverworks chip.
   Ken Brownfield <brownfld@irridia.com>

- Make the ata_operations methods immune against device type drivers,
   which donot provide them by separating the access to them out. Audit
   them all.

- Resynchronize with 2.5.6-pre1.

- Remove unused IDE_DRIVE_CMD, IDE_DRIVE_TASK, IDE_DRIVE_TASK_MASK,
   IDE_DRIVE_TASKFILE macros.

- Disable configuration of the task file stuff. It is going to go away
   and will be replaced by a truly abstract interface based on
   functionality and *not* direct mess-up of hardware.

- Resync with 2.5.6-pre2.

- Add HPT entries to the fall-back list, since otherwise the driver
   won'trecognize the drives. We will have to make this the default
   behavior for allnot recognized host chip types.

- Fix compilation with no PCI host chip support enabled.

- Apply the overflow fixes for HPT366 by Vojtech Pavlik.

- Kill the one-shoot functions ide_wait_cmd_taks() ide_wait_cmd() by
   moving them to the places where they are actually used. Fix a
   potential buffer overflow on the way.

- Fix usage of ide.c as module. Thanks to Adam J. Richter for figuring
   out what was wrong.

- Various cleanups all along as well as removal of TONS of
   unfinished/dead code.

I think it's sometimes better to remove stuff, which isn't there,
instead of hoping for a "magical day" where it will be finished.