LXR linux/include/linux/dma-mapping.h

   1#ifndef _ASM_LINUX_DMA_MAPPING_H
   2#define _ASM_LINUX_DMA_MAPPING_H
   3
   4#include <linux/device.h>
   5#include <linux/err.h>
   6
   7/* These definitions mirror those in pci.h, so they can be used
   8 * interchangeably with their PCI_ counterparts */
   9enum dma_data_direction {
  10        DMA_BIDIRECTIONAL = 0,
  11        DMA_TO_DEVICE = 1,
  12        DMA_FROM_DEVICE = 2,
  13        DMA_NONE = 3,
  14};
  15
  16#define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
  17
  18/*
  19 * NOTE: do not use the below macros in new code and do not add new definitions
  20 * here.
  21 *
  22 * Instead, just open-code DMA_BIT_MASK(n) within your driver
  23 */
  24#define DMA_64BIT_MASK  DMA_BIT_MASK(64)
  25#define DMA_48BIT_MASK  DMA_BIT_MASK(48)
  26#define DMA_47BIT_MASK  DMA_BIT_MASK(47)
  27#define DMA_40BIT_MASK  DMA_BIT_MASK(40)
  28#define DMA_39BIT_MASK  DMA_BIT_MASK(39)
  29#define DMA_35BIT_MASK  DMA_BIT_MASK(35)
  30#define DMA_32BIT_MASK  DMA_BIT_MASK(32)
  31#define DMA_31BIT_MASK  DMA_BIT_MASK(31)
  32#define DMA_30BIT_MASK  DMA_BIT_MASK(30)
  33#define DMA_29BIT_MASK  DMA_BIT_MASK(29)
  34#define DMA_28BIT_MASK  DMA_BIT_MASK(28)
  35#define DMA_24BIT_MASK  DMA_BIT_MASK(24)
  36
  37#define DMA_MASK_NONE   0x0ULL
  38
  39static inline int valid_dma_direction(int dma_direction)
  40{
  41        return ((dma_direction == DMA_BIDIRECTIONAL) ||
  42                (dma_direction == DMA_TO_DEVICE) ||
  43                (dma_direction == DMA_FROM_DEVICE));
  44}
  45
  46static inline int is_device_dma_capable(struct device *dev)
  47{
  48        return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
  49}
  50
  51#ifdef CONFIG_HAS_DMA
  52#include <asm/dma-mapping.h>
  53#else
  54#include <asm-generic/dma-mapping-broken.h>
  55#endif
  56
  57/* Backwards compat, remove in 2.7.x */
  58#define dma_sync_single         dma_sync_single_for_cpu
  59#define dma_sync_sg             dma_sync_sg_for_cpu
  60
  61extern u64 dma_get_required_mask(struct device *dev);
  62
  63/* flags for the coherent memory api */
  64#define DMA_MEMORY_MAP                  0x01
  65#define DMA_MEMORY_IO                   0x02
  66#define DMA_MEMORY_INCLUDES_CHILDREN    0x04
  67#define DMA_MEMORY_EXCLUSIVE            0x08
  68
  69#ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
  70static inline int
  71dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
  72                            dma_addr_t device_addr, size_t size, int flags)
  73{
  74        return 0;
  75}
  76
  77static inline void
  78dma_release_declared_memory(struct device *dev)
  79{
  80}
  81
  82static inline void *
  83dma_mark_declared_memory_occupied(struct device *dev,
  84                                  dma_addr_t device_addr, size_t size)
  85{
  86        return ERR_PTR(-EBUSY);
  87}
  88#endif
  89
  90/*
  91 * Managed DMA API
  92 */
  93extern void *dmam_alloc_coherent(struct device *dev, size_t size,
  94                                 dma_addr_t *dma_handle, gfp_t gfp);
  95extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
  96                               dma_addr_t dma_handle);
  97extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
  98                                    dma_addr_t *dma_handle, gfp_t gfp);
  99extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 100                                  dma_addr_t dma_handle);
 101#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 102extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
 103                                        dma_addr_t device_addr, size_t size,
 104                                        int flags);
 105extern void dmam_release_declared_memory(struct device *dev);
 106#else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 107static inline int dmam_declare_coherent_memory(struct device *dev,
 108                                dma_addr_t bus_addr, dma_addr_t device_addr,
 109                                size_t size, gfp_t gfp)
 110{
 111        return 0;
 112}
 113
 114static inline void dmam_release_declared_memory(struct device *dev)
 115{
 116}
 117#endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 118
 119#endif
 120