[PATCH v5 2/6] arch: unify ioremap prototypes and macro aliases

Geert Uytterhoeven geert at linux-m68k.org
Wed Jul 1 00:19:29 PDT 2015

On Wed, Jul 1, 2015 at 8:59 AM, Christoph Hellwig <hch at lst.de> wrote:
> On Wed, Jul 01, 2015 at 08:55:57AM +0200, Geert Uytterhoeven wrote:
>> >
>> > I think doing this at runtime might be a better idea.  E.g. a
>> > ioremap_flags with the CACHED argument will return -EOPNOTSUP unless
>> > actually implemented.  On various architectures different CPUs or
>> > boards will have different capabilities in this area.
>> So it would be the responsibility of the caller to fall back from
>> ioremap(..., CACHED) to ioremap(..., UNCACHED)?
>> I.e. all drivers using it should be changed...
> All of the zero users we currently have will need to be changed, yes.

Good. Less work to convert all of these ;-)

> Note that I propose to leave ioremap(), aka ioremap_flags(..., 0) as
> a default that always has to work, -EOPNOTSUP is only a valid return
> value for non-default flaga.




Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

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