[PATCH 22/24] scsi: eesox: use __iomem pointers for MMIO

Russell King - ARM Linux linux at arm.linux.org.uk
Fri Sep 14 19:27:03 EDT 2012

On Fri, Sep 14, 2012 at 11:34:50PM +0200, Arnd Bergmann wrote:
> ARM is moving to stricter checks on readl/write functions,
> so we need to use the correct types everywhere.

There's nothing wrong with const iomem pointers.  If you think
otherwise, patch x86 not to use const in its accessor implementation
and watch the reaction:

#define build_mmio_read(name, size, type, reg, barrier) \
static inline type name(const volatile void __iomem *addr) \
{ type ret; asm volatile("mov" size " %1,%0":reg (ret) \
:"m" (*(volatile type __force *)addr) barrier); return ret; }

build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
build_mmio_read(readl, "l", unsigned int, "=r", :"memory")

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