This patch fixes a microcode lockup in my CD-ROM adapters when a blank CD
is inserted.  However, do not try to burn CDs yet!  I'm pretty sure that
trying it will end in coasters.

 - Fix a few cases where we were unable to resynchronize with replies
   for previous commands. The main thing is to keep reading replies
   in case of a stall. This is done with the new state CLRRS.
 - Since I am forgetting the basic state machine already, document it.
 - Move counter increments in the looping path in its own function.
 - Fix a harmless buglet in case CSW read fails to submit: do not
   override state.
 - Implement the Alan Stern's idea for adaptive signature checking.

Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>