introduce DMA_MASK_NONE as a signal for unable to do DMA
[linux-2.6.git] / 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 */
9 enum 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_64BIT_MASK  0xffffffffffffffffULL
17 #define DMA_48BIT_MASK  0x0000ffffffffffffULL
18 #define DMA_40BIT_MASK  0x000000ffffffffffULL
19 #define DMA_39BIT_MASK  0x0000007fffffffffULL
20 #define DMA_32BIT_MASK  0x00000000ffffffffULL
21 #define DMA_31BIT_MASK  0x000000007fffffffULL
22 #define DMA_30BIT_MASK  0x000000003fffffffULL
23 #define DMA_29BIT_MASK  0x000000001fffffffULL
24 #define DMA_28BIT_MASK  0x000000000fffffffULL
25 #define DMA_24BIT_MASK  0x0000000000ffffffULL
26
27 #define DMA_MASK_NONE   0x0ULL
28
29 static inline int valid_dma_direction(int dma_direction)
30 {
31         return ((dma_direction == DMA_BIDIRECTIONAL) ||
32                 (dma_direction == DMA_TO_DEVICE) ||
33                 (dma_direction == DMA_FROM_DEVICE));
34 }
35
36 static inline int is_device_dma_capable(struct device *dev)
37 {
38         return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
39 }
40
41 #ifdef CONFIG_HAS_DMA
42 #include <asm/dma-mapping.h>
43 #else
44 #include <asm-generic/dma-mapping-broken.h>
45 #endif
46
47 /* Backwards compat, remove in 2.7.x */
48 #define dma_sync_single         dma_sync_single_for_cpu
49 #define dma_sync_sg             dma_sync_sg_for_cpu
50
51 extern u64 dma_get_required_mask(struct device *dev);
52
53 /* flags for the coherent memory api */
54 #define DMA_MEMORY_MAP                  0x01
55 #define DMA_MEMORY_IO                   0x02
56 #define DMA_MEMORY_INCLUDES_CHILDREN    0x04
57 #define DMA_MEMORY_EXCLUSIVE            0x08
58
59 #ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
60 static inline int
61 dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
62                             dma_addr_t device_addr, size_t size, int flags)
63 {
64         return 0;
65 }
66
67 static inline void
68 dma_release_declared_memory(struct device *dev)
69 {
70 }
71
72 static inline void *
73 dma_mark_declared_memory_occupied(struct device *dev,
74                                   dma_addr_t device_addr, size_t size)
75 {
76         return ERR_PTR(-EBUSY);
77 }
78 #endif
79
80 /*
81  * Managed DMA API
82  */
83 extern void *dmam_alloc_coherent(struct device *dev, size_t size,
84                                  dma_addr_t *dma_handle, gfp_t gfp);
85 extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
86                                dma_addr_t dma_handle);
87 extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
88                                     dma_addr_t *dma_handle, gfp_t gfp);
89 extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
90                                   dma_addr_t dma_handle);
91 #ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
92 extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
93                                         dma_addr_t device_addr, size_t size,
94                                         int flags);
95 extern void dmam_release_declared_memory(struct device *dev);
96 #else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
97 static inline int dmam_declare_coherent_memory(struct device *dev,
98                                 dma_addr_t bus_addr, dma_addr_t device_addr,
99                                 size_t size, gfp_t gfp)
100 {
101         return 0;
102 }
103
104 static inline void dmam_release_declared_memory(struct device *dev)
105 {
106 }
107 #endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
108
109 #endif