1 /*
2 * Copyright (c) 2015-2018 François Tigeot <ftigeot@wolfpond.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice unmodified, this list of conditions, and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #ifndef _LINUX_DMA_MAPPING_H_
28 #define _LINUX_DMA_MAPPING_H_
29
30 #include <linux/string.h>
31 #include <linux/device.h>
32 #include <linux/err.h>
33 #include <linux/dma-direction.h>
34 #include <linux/scatterlist.h>
35 #include <linux/bug.h>
36
37 #include <asm/dma-mapping.h>
38
39 #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : (1ULL<<(n)) - 1)
40
41 static inline dma_addr_t
dma_map_page(struct device * dev,struct page * page,unsigned long offset,size_t size,enum dma_data_direction direction)42 dma_map_page(struct device *dev, struct page *page,
43 unsigned long offset, size_t size, enum dma_data_direction direction)
44 {
45 return VM_PAGE_TO_PHYS((struct vm_page *)page) + offset;
46 }
47
dma_unmap_page(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir)48 static inline void dma_unmap_page(struct device *dev, dma_addr_t addr,
49 size_t size, enum dma_data_direction dir)
50 {
51 }
52
53 static inline int
dma_mapping_error(struct device * dev,dma_addr_t dma_addr)54 dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
55 {
56 return 0;
57 }
58
59 static inline int
dma_map_sg(struct device * dev,struct scatterlist * sg,int nents,enum dma_data_direction dir)60 dma_map_sg(struct device *dev, struct scatterlist *sg,
61 int nents, enum dma_data_direction dir)
62 {
63 struct scatterlist *s;
64 int i;
65
66 for_each_sg(sg, s, nents, i)
67 s->dma_address = sg_phys(s);
68
69 return nents;
70 }
71
72 static inline void
dma_unmap_sg(struct device * dev,struct scatterlist * sg,int nents,enum dma_data_direction dir)73 dma_unmap_sg(struct device *dev, struct scatterlist *sg,
74 int nents, enum dma_data_direction dir)
75 {
76 }
77
78 void *
79 dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
80 gfp_t flag);
81
82 void
83 dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
84 dma_addr_t dma_handle);
85
86 #endif /* _LINUX_DMA-MAPPING_H_ */
87