Re: PCCARD eject freeze (was Re: your mail)

[Mike Smith]

> In message <[EMAIL PROTECTED]> "Matthew N. 
>Dodd" writes:
> : On Thu, 2 Dec 1999, Nick Hibma wrote:
> : > PCMCIA has the problem that the hardware register you are talking to can
> : > disappear on the spot, between 2 outb()s.
> : 
> : Can't we do something about this using bus_space?  This would give us a
> : fair bit of overhead for PCMCIA devices as well as require us to more
> : tightly couple newbus and bus_space (we'd probably want to 'cache' a
> : function pointer to the method to avoid method lookup overhead.)
> 
> I had the same thought, but w/o a signal or other out of band error
> communication, I'm not sure how to implement this.

You can't without a race.  You'd have to poll the hardware before and 
after every I/O operation to ensure that it was still there.  Yick.

-- 
\\ Give a man a fish, and you feed him for a day. \\  Mike Smith
\\ Tell him he should learn how to fish himself,  \\  [EMAIL PROTECTED]
\\ and he'll hate you for a lifetime.             \\  [EMAIL PROTECTED]




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