alistair23-linux/include/linux/io-mapping.h
Paul Bolle 395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00

164 lines
3.6 KiB
C

/*
* Copyright © 2008 Keith Packard <keithp@keithp.com>
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef _LINUX_IO_MAPPING_H
#define _LINUX_IO_MAPPING_H
#include <linux/types.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <asm/page.h>
/*
* The io_mapping mechanism provides an abstraction for mapping
* individual pages from an io device to the CPU in an efficient fashion.
*
* See Documentation/io-mapping.txt
*/
#ifdef CONFIG_HAVE_ATOMIC_IOMAP
#include <asm/iomap.h>
struct io_mapping {
resource_size_t base;
unsigned long size;
pgprot_t prot;
};
/*
* For small address space machines, mapping large objects
* into the kernel virtual space isn't practical. Where
* available, use fixmap support to dynamically map pages
* of the object at run time.
*/
static inline struct io_mapping *
io_mapping_create_wc(resource_size_t base, unsigned long size)
{
struct io_mapping *iomap;
pgprot_t prot;
iomap = kmalloc(sizeof(*iomap), GFP_KERNEL);
if (!iomap)
goto out_err;
if (iomap_create_wc(base, size, &prot))
goto out_free;
iomap->base = base;
iomap->size = size;
iomap->prot = prot;
return iomap;
out_free:
kfree(iomap);
out_err:
return NULL;
}
static inline void
io_mapping_free(struct io_mapping *mapping)
{
iomap_free(mapping->base, mapping->size);
kfree(mapping);
}
/* Atomic map/unmap */
static inline void __iomem *
io_mapping_map_atomic_wc(struct io_mapping *mapping,
unsigned long offset)
{
resource_size_t phys_addr;
unsigned long pfn;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
pfn = (unsigned long) (phys_addr >> PAGE_SHIFT);
return iomap_atomic_prot_pfn(pfn, mapping->prot);
}
static inline void
io_mapping_unmap_atomic(void __iomem *vaddr)
{
iounmap_atomic(vaddr);
}
static inline void __iomem *
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
{
resource_size_t phys_addr;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
return ioremap_wc(phys_addr, PAGE_SIZE);
}
static inline void
io_mapping_unmap(void __iomem *vaddr)
{
iounmap(vaddr);
}
#else
/* this struct isn't actually defined anywhere */
struct io_mapping;
/* Create the io_mapping object*/
static inline struct io_mapping *
io_mapping_create_wc(resource_size_t base, unsigned long size)
{
return (struct io_mapping __force *) ioremap_wc(base, size);
}
static inline void
io_mapping_free(struct io_mapping *mapping)
{
iounmap((void __force __iomem *) mapping);
}
/* Atomic map/unmap */
static inline void __iomem *
io_mapping_map_atomic_wc(struct io_mapping *mapping,
unsigned long offset)
{
return ((char __force __iomem *) mapping) + offset;
}
static inline void
io_mapping_unmap_atomic(void __iomem *vaddr)
{
}
/* Non-atomic map/unmap */
static inline void __iomem *
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
{
return ((char __force __iomem *) mapping) + offset;
}
static inline void
io_mapping_unmap(void __iomem *vaddr)
{
}
#endif /* HAVE_ATOMIC_IOMAP */
#endif /* _LINUX_IO_MAPPING_H */