Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * |
3 | * generic helper functions for video4linux capture buffers, to handle | |
c7b0ac05 MCC |
4 | * memory management and PCI DMA. |
5 | * Right now, bttv, saa7134, saa7146 and cx88 use it. | |
1da177e4 LT |
6 | * |
7 | * The functions expect the hardware being able to scatter gatter | |
8 | * (i.e. the buffers are not linear in physical memory, but fragmented | |
9 | * into PAGE_SIZE chunks). They also assume the driver does not need | |
c7b0ac05 MCC |
10 | * to touch the video data. |
11 | * | |
12 | * device specific map/unmap/sync stuff now are mapped as file operations | |
13 | * to allow its usage by USB and virtual devices. | |
1da177e4 LT |
14 | * |
15 | * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> | |
c7b0ac05 MCC |
16 | * (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org> |
17 | * (c) 2006 Ted Walther and John Sokol | |
1da177e4 LT |
18 | * |
19 | * This program is free software; you can redistribute it and/or modify | |
20 | * it under the terms of the GNU General Public License as published by | |
21 | * the Free Software Foundation; either version 2 of the License, or | |
22 | * (at your option) any later version. | |
23 | */ | |
24 | ||
79436633 | 25 | #include <linux/videodev2.h> |
401998fa | 26 | #include <linux/poll.h> |
1da177e4 LT |
27 | |
28 | #define UNSET (-1U) | |
29 | ||
30 | /* --------------------------------------------------------------------- */ | |
31 | ||
32 | /* | |
33 | * Return a scatterlist for some page-aligned vmalloc()'ed memory | |
34 | * block (NULL on errors). Memory for the scatterlist is allocated | |
35 | * using kmalloc. The caller must free the memory. | |
36 | */ | |
37 | struct scatterlist* videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages); | |
38 | ||
39 | /* | |
40 | * Return a scatterlist for a an array of userpages (NULL on errors). | |
41 | * Memory for the scatterlist is allocated using kmalloc. The caller | |
42 | * must free the memory. | |
43 | */ | |
44 | struct scatterlist* videobuf_pages_to_sg(struct page **pages, int nr_pages, | |
45 | int offset); | |
46 | ||
c7b0ac05 MCC |
47 | struct videobuf_buffer; |
48 | struct videobuf_queue; | |
49 | ||
1da177e4 LT |
50 | /* --------------------------------------------------------------------- */ |
51 | ||
52 | /* | |
53 | * A small set of helper functions to manage buffers (both userland | |
54 | * and kernel) for DMA. | |
55 | * | |
56 | * videobuf_dma_init_*() | |
57 | * creates a buffer. The userland version takes a userspace | |
58 | * pointer + length. The kernel version just wants the size and | |
59 | * does memory allocation too using vmalloc_32(). | |
60 | * | |
c7b0ac05 | 61 | * videobuf_dma_*() |
1da177e4 LT |
62 | * see Documentation/DMA-mapping.txt, these functions to |
63 | * basically the same. The map function does also build a | |
64 | * scatterlist for the buffer (and unmap frees it ...) | |
65 | * | |
66 | * videobuf_dma_free() | |
67 | * no comment ... | |
68 | * | |
69 | */ | |
70 | ||
71 | struct videobuf_dmabuf { | |
72 | u32 magic; | |
73 | ||
74 | /* for userland buffer */ | |
75 | int offset; | |
76 | struct page **pages; | |
77 | ||
78 | /* for kernel buffers */ | |
79 | void *vmalloc; | |
80 | ||
b50e7fe9 MCC |
81 | /* Stores the userspace pointer to vmalloc area */ |
82 | void *varea; | |
83 | ||
1da177e4 LT |
84 | /* for overlay buffers (pci-pci dma) */ |
85 | dma_addr_t bus_addr; | |
86 | ||
87 | /* common */ | |
88 | struct scatterlist *sglist; | |
89 | int sglen; | |
90 | int nr_pages; | |
91 | int direction; | |
92 | }; | |
93 | ||
94 | void videobuf_dma_init(struct videobuf_dmabuf *dma); | |
95 | int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction, | |
96 | unsigned long data, unsigned long size); | |
97 | int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction, | |
98 | int nr_pages); | |
99 | int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction, | |
100 | dma_addr_t addr, int nr_pages); | |
1da177e4 LT |
101 | int videobuf_dma_free(struct videobuf_dmabuf *dma); |
102 | ||
c7b0ac05 MCC |
103 | int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma); |
104 | int videobuf_dma_sync(struct videobuf_queue* q,struct videobuf_dmabuf *dma); | |
105 | int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma); | |
106 | ||
107 | /*FIXME: these variants are used only on *-alsa code, where videobuf is | |
108 | * used without queue | |
109 | */ | |
110 | int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma); | |
111 | int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma); | |
112 | ||
1da177e4 LT |
113 | /* --------------------------------------------------------------------- */ |
114 | ||
115 | /* | |
116 | * A small set of helper functions to manage video4linux buffers. | |
117 | * | |
118 | * struct videobuf_buffer holds the data structures used by the helper | |
119 | * functions, additionally some commonly used fields for v4l buffers | |
120 | * (width, height, lists, waitqueue) are in there. That struct should | |
121 | * be used as first element in the drivers buffer struct. | |
122 | * | |
123 | * about the mmap helpers (videobuf_mmap_*): | |
124 | * | |
125 | * The mmaper function allows to map any subset of contingous buffers. | |
126 | * This includes one mmap() call for all buffers (which the original | |
127 | * video4linux API uses) as well as one mmap() for every single buffer | |
128 | * (which v4l2 uses). | |
129 | * | |
130 | * If there is a valid mapping for a buffer, buffer->baddr/bsize holds | |
131 | * userspace address + size which can be feeded into the | |
132 | * videobuf_dma_init_user function listed above. | |
133 | * | |
134 | */ | |
135 | ||
1da177e4 LT |
136 | struct videobuf_mapping { |
137 | unsigned int count; | |
138 | unsigned long start; | |
139 | unsigned long end; | |
140 | struct videobuf_queue *q; | |
141 | }; | |
142 | ||
143 | enum videobuf_state { | |
144 | STATE_NEEDS_INIT = 0, | |
145 | STATE_PREPARED = 1, | |
146 | STATE_QUEUED = 2, | |
147 | STATE_ACTIVE = 3, | |
148 | STATE_DONE = 4, | |
149 | STATE_ERROR = 5, | |
150 | STATE_IDLE = 6, | |
151 | }; | |
152 | ||
153 | struct videobuf_buffer { | |
154 | unsigned int i; | |
155 | u32 magic; | |
156 | ||
157 | /* info about the buffer */ | |
158 | unsigned int width; | |
159 | unsigned int height; | |
160 | unsigned int bytesperline; /* use only if != 0 */ | |
161 | unsigned long size; | |
162 | unsigned int input; | |
163 | enum v4l2_field field; | |
164 | enum videobuf_state state; | |
165 | struct videobuf_dmabuf dma; | |
166 | struct list_head stream; /* QBUF/DQBUF list */ | |
167 | ||
168 | /* for mmap'ed buffers */ | |
169 | enum v4l2_memory memory; | |
170 | size_t boff; /* buffer offset (mmap + overlay) */ | |
171 | size_t bsize; /* buffer size */ | |
172 | unsigned long baddr; /* buffer addr (userland ptr!) */ | |
173 | struct videobuf_mapping *map; | |
174 | ||
175 | /* touched by irq handler */ | |
176 | struct list_head queue; | |
177 | wait_queue_head_t done; | |
178 | unsigned int field_count; | |
179 | struct timeval ts; | |
180 | }; | |
181 | ||
c7b0ac05 MCC |
182 | typedef int (vb_map_sg_t)(void *dev,struct scatterlist *sglist,int nr_pages, |
183 | int direction); | |
184 | ||
185 | ||
1da177e4 LT |
186 | struct videobuf_queue_ops { |
187 | int (*buf_setup)(struct videobuf_queue *q, | |
188 | unsigned int *count, unsigned int *size); | |
189 | int (*buf_prepare)(struct videobuf_queue *q, | |
190 | struct videobuf_buffer *vb, | |
191 | enum v4l2_field field); | |
192 | void (*buf_queue)(struct videobuf_queue *q, | |
193 | struct videobuf_buffer *vb); | |
194 | void (*buf_release)(struct videobuf_queue *q, | |
195 | struct videobuf_buffer *vb); | |
c7b0ac05 MCC |
196 | |
197 | /* Helper operations - device dependent. | |
198 | * If null, videobuf_init defaults all to PCI handling | |
199 | */ | |
200 | ||
201 | vb_map_sg_t *vb_map_sg; | |
202 | vb_map_sg_t *vb_dma_sync_sg; | |
203 | vb_map_sg_t *vb_unmap_sg; | |
1da177e4 LT |
204 | }; |
205 | ||
206 | struct videobuf_queue { | |
3593cab5 | 207 | struct mutex lock; |
1da177e4 | 208 | spinlock_t *irqlock; |
c7b0ac05 | 209 | void *dev; /* on pci, points to struct pci_dev */ |
1da177e4 LT |
210 | |
211 | enum v4l2_buf_type type; | |
212 | unsigned int inputs; /* for V4L2_BUF_FLAG_INPUT */ | |
213 | unsigned int msize; | |
214 | enum v4l2_field field; | |
215 | enum v4l2_field last; /* for field=V4L2_FIELD_ALTERNATE */ | |
216 | struct videobuf_buffer *bufs[VIDEO_MAX_FRAME]; | |
217 | struct videobuf_queue_ops *ops; | |
218 | ||
219 | /* capture via mmap() + ioctl(QBUF/DQBUF) */ | |
220 | unsigned int streaming; | |
221 | struct list_head stream; | |
222 | ||
223 | /* capture via read() */ | |
224 | unsigned int reading; | |
225 | unsigned int read_off; | |
226 | struct videobuf_buffer *read_buf; | |
227 | ||
228 | /* driver private data */ | |
229 | void *priv_data; | |
230 | }; | |
231 | ||
232 | void* videobuf_alloc(unsigned int size); | |
233 | int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr); | |
c7b0ac05 MCC |
234 | int videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb, |
235 | struct v4l2_framebuffer *fbuf); | |
236 | ||
237 | /* Maps fops to PCI stuff */ | |
238 | void videobuf_queue_pci(struct videobuf_queue* q); | |
1da177e4 LT |
239 | |
240 | void videobuf_queue_init(struct videobuf_queue *q, | |
241 | struct videobuf_queue_ops *ops, | |
c7b0ac05 | 242 | void *dev, |
1da177e4 LT |
243 | spinlock_t *irqlock, |
244 | enum v4l2_buf_type type, | |
245 | enum v4l2_field field, | |
246 | unsigned int msize, | |
247 | void *priv); | |
248 | int videobuf_queue_is_busy(struct videobuf_queue *q); | |
249 | void videobuf_queue_cancel(struct videobuf_queue *q); | |
250 | ||
251 | enum v4l2_field videobuf_next_field(struct videobuf_queue *q); | |
252 | void videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb, | |
253 | enum v4l2_buf_type type); | |
254 | int videobuf_reqbufs(struct videobuf_queue *q, | |
255 | struct v4l2_requestbuffers *req); | |
256 | int videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b); | |
257 | int videobuf_qbuf(struct videobuf_queue *q, | |
258 | struct v4l2_buffer *b); | |
259 | int videobuf_dqbuf(struct videobuf_queue *q, | |
260 | struct v4l2_buffer *b, int nonblocking); | |
261 | int videobuf_streamon(struct videobuf_queue *q); | |
262 | int videobuf_streamoff(struct videobuf_queue *q); | |
263 | ||
264 | int videobuf_read_start(struct videobuf_queue *q); | |
265 | void videobuf_read_stop(struct videobuf_queue *q); | |
266 | ssize_t videobuf_read_stream(struct videobuf_queue *q, | |
267 | char __user *data, size_t count, loff_t *ppos, | |
268 | int vbihack, int nonblocking); | |
269 | ssize_t videobuf_read_one(struct videobuf_queue *q, | |
270 | char __user *data, size_t count, loff_t *ppos, | |
271 | int nonblocking); | |
272 | unsigned int videobuf_poll_stream(struct file *file, | |
273 | struct videobuf_queue *q, | |
274 | poll_table *wait); | |
275 | ||
276 | int videobuf_mmap_setup(struct videobuf_queue *q, | |
277 | unsigned int bcount, unsigned int bsize, | |
278 | enum v4l2_memory memory); | |
279 | int videobuf_mmap_free(struct videobuf_queue *q); | |
280 | int videobuf_mmap_mapper(struct videobuf_queue *q, | |
281 | struct vm_area_struct *vma); | |
282 | ||
283 | /* --------------------------------------------------------------------- */ | |
284 | ||
285 | /* | |
286 | * Local variables: | |
287 | * c-basic-offset: 8 | |
288 | * End: | |
289 | */ |