Messages in this thread | | | Date | Tue, 18 Sep 2007 15:07:23 -0400 | From | "Luis R. Rodriguez" <> | Subject | Re: [PATCH] Clarify pci_iomap() usage for MMIO-only devices |
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On 9/18/07, Linus Torvalds <torvalds@linux-foundation.org> wrote: > > > On Tue, 18 Sep 2007, Luis R. Rodriguez wrote: > > > > Alright, here is the same patch inline with s/recommended/required/ language: > > Well, the thing is, I'm not at all sure that I agree with this. > > If you use ioport_map/unmap, then you really *should* access them with the > proper iomem accessors (ioread/iowrite). The fact that it may happen to > work (when using the default lib/iomap.c implementation, at least) on > some architectures and with the current implementation still doesn't mean > that you should necessarily use readb/writeb. > > After all, you cannot use "inb/outb" on it, even if would happen to be an > IO address. > > So what is this usage that wants to use the bogus accessor? Why not fix > that instead of adding documentation for something that is very arguably > something we want to *avoid* having people do!
ACK -- driver developers use this just to save themselves a few lines from calling pci_resource_start() and friends. How about having an inline which does what pci_iomap() does except it doesn't call ioport_map() ? I am just not sure where this would go..
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