Commit | Line | Data |
---|---|---|
74bc7cee AK |
1 | #ifndef _DMA_ATTR_H |
2 | #define _DMA_ATTR_H | |
3 | ||
4 | #include <linux/bitmap.h> | |
5 | #include <linux/bitops.h> | |
6 | #include <linux/bug.h> | |
7 | ||
8 | /** | |
9 | * an enum dma_attr represents an attribute associated with a DMA | |
10 | * mapping. The semantics of each attribute should be defined in | |
11 | * Documentation/DMA-attributes.txt. | |
12 | */ | |
13 | enum dma_attr { | |
14 | DMA_ATTR_WRITE_BARRIER, | |
1ed6af73 | 15 | DMA_ATTR_WEAK_ORDERING, |
8a413432 | 16 | DMA_ATTR_WRITE_COMBINE, |
64d70fe5 | 17 | DMA_ATTR_NON_CONSISTENT, |
d5724f17 | 18 | DMA_ATTR_NO_KERNEL_MAPPING, |
bdf5e487 | 19 | DMA_ATTR_SKIP_CPU_SYNC, |
74bc7cee AK |
20 | DMA_ATTR_MAX, |
21 | }; | |
22 | ||
23 | #define __DMA_ATTRS_LONGS BITS_TO_LONGS(DMA_ATTR_MAX) | |
24 | ||
25 | /** | |
26 | * struct dma_attrs - an opaque container for DMA attributes | |
27 | * @flags - bitmask representing a collection of enum dma_attr | |
28 | */ | |
29 | struct dma_attrs { | |
30 | unsigned long flags[__DMA_ATTRS_LONGS]; | |
31 | }; | |
32 | ||
33 | #define DEFINE_DMA_ATTRS(x) \ | |
34 | struct dma_attrs x = { \ | |
35 | .flags = { [0 ... __DMA_ATTRS_LONGS-1] = 0 }, \ | |
36 | } | |
37 | ||
38 | static inline void init_dma_attrs(struct dma_attrs *attrs) | |
39 | { | |
40 | bitmap_zero(attrs->flags, __DMA_ATTRS_LONGS); | |
41 | } | |
42 | ||
43 | #ifdef CONFIG_HAVE_DMA_ATTRS | |
44 | /** | |
45 | * dma_set_attr - set a specific attribute | |
46 | * @attr: attribute to set | |
47 | * @attrs: struct dma_attrs (may be NULL) | |
48 | */ | |
49 | static inline void dma_set_attr(enum dma_attr attr, struct dma_attrs *attrs) | |
50 | { | |
51 | if (attrs == NULL) | |
52 | return; | |
53 | BUG_ON(attr >= DMA_ATTR_MAX); | |
54 | __set_bit(attr, attrs->flags); | |
55 | } | |
56 | ||
57 | /** | |
58 | * dma_get_attr - check for a specific attribute | |
59 | * @attr: attribute to set | |
60 | * @attrs: struct dma_attrs (may be NULL) | |
61 | */ | |
62 | static inline int dma_get_attr(enum dma_attr attr, struct dma_attrs *attrs) | |
63 | { | |
64 | if (attrs == NULL) | |
65 | return 0; | |
66 | BUG_ON(attr >= DMA_ATTR_MAX); | |
67 | return test_bit(attr, attrs->flags); | |
68 | } | |
69 | #else /* !CONFIG_HAVE_DMA_ATTRS */ | |
70 | static inline void dma_set_attr(enum dma_attr attr, struct dma_attrs *attrs) | |
71 | { | |
72 | } | |
73 | ||
74 | static inline int dma_get_attr(enum dma_attr attr, struct dma_attrs *attrs) | |
75 | { | |
76 | return 0; | |
77 | } | |
78 | #endif /* CONFIG_HAVE_DMA_ATTRS */ | |
79 | #endif /* _DMA_ATTR_H */ |