xref: /linux/include/sound/memalloc.h (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
3  *                   Takashi Iwai <tiwai@suse.de>
4  *
5  *  Generic memory allocators
6  *
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  *
22  */
23 
24 #ifndef __SOUND_MEMALLOC_H
25 #define __SOUND_MEMALLOC_H
26 
27 struct device;
28 
29 /*
30  * buffer device info
31  */
32 struct snd_dma_device {
33 	int type;			/* SNDRV_DMA_TYPE_XXX */
34 	struct device *dev;		/* generic device */
35 };
36 
37 #ifndef snd_dma_pci_data
38 #define snd_dma_pci_data(pci)	(&(pci)->dev)
39 #define snd_dma_isa_data()	NULL
40 #define snd_dma_sbus_data(sbus)	((struct device *)(sbus))
41 #define snd_dma_continuous_data(x)	((struct device *)(unsigned long)(x))
42 #endif
43 
44 
45 /*
46  * buffer types
47  */
48 #define SNDRV_DMA_TYPE_UNKNOWN		0	/* not defined */
49 #define SNDRV_DMA_TYPE_CONTINUOUS	1	/* continuous no-DMA memory */
50 #define SNDRV_DMA_TYPE_DEV		2	/* generic device continuous */
51 #define SNDRV_DMA_TYPE_DEV_SG		3	/* generic device SG-buffer */
52 #define SNDRV_DMA_TYPE_SBUS		4	/* SBUS continuous */
53 
54 /*
55  * info for buffer allocation
56  */
57 struct snd_dma_buffer {
58 	struct snd_dma_device dev;	/* device type */
59 	unsigned char *area;	/* virtual pointer */
60 	dma_addr_t addr;	/* physical address */
61 	size_t bytes;		/* buffer size in bytes */
62 	void *private_data;	/* private for allocator; don't touch */
63 };
64 
65 /*
66  * Scatter-Gather generic device pages
67  */
68 struct snd_sg_page {
69 	void *buf;
70 	dma_addr_t addr;
71 };
72 
73 struct snd_sg_buf {
74 	int size;	/* allocated byte size */
75 	int pages;	/* allocated pages */
76 	int tblsize;	/* allocated table size */
77 	struct snd_sg_page *table;	/* address table */
78 	struct page **page_table;	/* page table (for vmap/vunmap) */
79 	struct device *dev;
80 };
81 
82 /*
83  * return the pages matching with the given byte size
84  */
85 static inline unsigned int snd_sgbuf_aligned_pages(size_t size)
86 {
87 	return (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
88 }
89 
90 /*
91  * return the physical address at the corresponding offset
92  */
93 static inline dma_addr_t snd_sgbuf_get_addr(struct snd_sg_buf *sgbuf, size_t offset)
94 {
95 	return sgbuf->table[offset >> PAGE_SHIFT].addr + offset % PAGE_SIZE;
96 }
97 
98 
99 /* allocate/release a buffer */
100 int snd_dma_alloc_pages(int type, struct device *dev, size_t size,
101 			struct snd_dma_buffer *dmab);
102 int snd_dma_alloc_pages_fallback(int type, struct device *dev, size_t size,
103                                  struct snd_dma_buffer *dmab);
104 void snd_dma_free_pages(struct snd_dma_buffer *dmab);
105 
106 /* buffer-preservation managements */
107 
108 #define snd_dma_pci_buf_id(pci)	(((unsigned int)(pci)->vendor << 16) | (pci)->device)
109 
110 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id);
111 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id);
112 
113 /* basic memory allocation functions */
114 void *snd_malloc_pages(size_t size, gfp_t gfp_flags);
115 void snd_free_pages(void *ptr, size_t size);
116 
117 #endif /* __SOUND_MEMALLOC_H */
118 
119