Re: Should io(read|write)(8|16|32)_rep take (const|) volatile u(8|16|32) __iomem *addr?

[Jeff Garzik <jeff@garzik.org>]

Michael K. Edwards wrote:
> Doubtless this is on purpose, but it's not clear to me why that should
> be true for these particular functions/macros.  I shouldn't have to
> cast away the volatile on a pointer to hardware registers in order to
> pass it into writel(), should I?  And it shouldn't be forbidden for
> the caller to declare the pointer volatile so that the compiler
> catches attempts to pass it into non-volatile interfaces, should it?


Therein lies your bug:  you should not be annotating your __iomem 
pointers with volatile.

That's why volatile is found in the implementation and not the 
prototypes of the accessor functions.

	Jeff


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