1 /* 2 * videobuf2-core.h - Video Buffer 2 Core Framework 3 * 4 * Copyright (C) 2010 Samsung Electronics 5 * 6 * Author: Pawel Osciak <pawel@osciak.com> 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. 11 */ 12 #ifndef _MEDIA_VIDEOBUF2_CORE_H 13 #define _MEDIA_VIDEOBUF2_CORE_H 14 15 #include <linux/mm_types.h> 16 #include <linux/mutex.h> 17 #include <linux/poll.h> 18 #include <linux/dma-buf.h> 19 20 #define VB2_MAX_FRAME (32) 21 #define VB2_MAX_PLANES (8) 22 23 enum vb2_memory { 24 VB2_MEMORY_UNKNOWN = 0, 25 VB2_MEMORY_MMAP = 1, 26 VB2_MEMORY_USERPTR = 2, 27 VB2_MEMORY_DMABUF = 4, 28 }; 29 30 struct vb2_fileio_data; 31 struct vb2_threadio_data; 32 33 /** 34 * struct vb2_mem_ops - memory handling/memory allocator operations 35 * @alloc: allocate video memory and, optionally, allocator private data, 36 * return NULL on failure or a pointer to allocator private, 37 * per-buffer data on success; the returned private structure 38 * will then be passed as buf_priv argument to other ops in this 39 * structure. Additional gfp_flags to use when allocating the 40 * are also passed to this operation. These flags are from the 41 * gfp_flags field of vb2_queue. 42 * @put: inform the allocator that the buffer will no longer be used; 43 * usually will result in the allocator freeing the buffer (if 44 * no other users of this buffer are present); the buf_priv 45 * argument is the allocator private per-buffer structure 46 * previously returned from the alloc callback. 47 * @get_dmabuf: acquire userspace memory for a hardware operation; used for 48 * DMABUF memory types. 49 * @get_userptr: acquire userspace memory for a hardware operation; used for 50 * USERPTR memory types; vaddr is the address passed to the 51 * videobuf layer when queuing a video buffer of USERPTR type; 52 * should return an allocator private per-buffer structure 53 * associated with the buffer on success, NULL on failure; 54 * the returned private structure will then be passed as buf_priv 55 * argument to other ops in this structure. 56 * @put_userptr: inform the allocator that a USERPTR buffer will no longer 57 * be used. 58 * @attach_dmabuf: attach a shared struct dma_buf for a hardware operation; 59 * used for DMABUF memory types; dev is the alloc device 60 * dbuf is the shared dma_buf; returns NULL on failure; 61 * allocator private per-buffer structure on success; 62 * this needs to be used for further accesses to the buffer. 63 * @detach_dmabuf: inform the exporter of the buffer that the current DMABUF 64 * buffer is no longer used; the buf_priv argument is the 65 * allocator private per-buffer structure previously returned 66 * from the attach_dmabuf callback. 67 * @map_dmabuf: request for access to the dmabuf from allocator; the allocator 68 * of dmabuf is informed that this driver is going to use the 69 * dmabuf. 70 * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified 71 * that this driver is done using the dmabuf for now. 72 * @prepare: called every time the buffer is passed from userspace to the 73 * driver, useful for cache synchronisation, optional. 74 * @finish: called every time the buffer is passed back from the driver 75 * to the userspace, also optional. 76 * @vaddr: return a kernel virtual address to a given memory buffer 77 * associated with the passed private structure or NULL if no 78 * such mapping exists. 79 * @cookie: return allocator specific cookie for a given memory buffer 80 * associated with the passed private structure or NULL if not 81 * available. 82 * @num_users: return the current number of users of a memory buffer; 83 * return 1 if the videobuf layer (or actually the driver using 84 * it) is the only user. 85 * @mmap: setup a userspace mapping for a given memory buffer under 86 * the provided virtual memory region. 87 * 88 * Those operations are used by the videobuf2 core to implement the memory 89 * handling/memory allocators for each type of supported streaming I/O method. 90 * 91 * .. note:: 92 * #) Required ops for USERPTR types: get_userptr, put_userptr. 93 * 94 * #) Required ops for MMAP types: alloc, put, num_users, mmap. 95 * 96 * #) Required ops for read/write access types: alloc, put, num_users, vaddr. 97 * 98 * #) Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, map_dmabuf, unmap_dmabuf. 99 */ 100 struct vb2_mem_ops { 101 void *(*alloc)(struct device *dev, unsigned long attrs, 102 unsigned long size, enum dma_data_direction dma_dir, 103 gfp_t gfp_flags); 104 void (*put)(void *buf_priv); 105 struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags); 106 107 void *(*get_userptr)(struct device *dev, unsigned long vaddr, 108 unsigned long size, 109 enum dma_data_direction dma_dir); 110 void (*put_userptr)(void *buf_priv); 111 112 void (*prepare)(void *buf_priv); 113 void (*finish)(void *buf_priv); 114 115 void *(*attach_dmabuf)(struct device *dev, struct dma_buf *dbuf, 116 unsigned long size, 117 enum dma_data_direction dma_dir); 118 void (*detach_dmabuf)(void *buf_priv); 119 int (*map_dmabuf)(void *buf_priv); 120 void (*unmap_dmabuf)(void *buf_priv); 121 122 void *(*vaddr)(void *buf_priv); 123 void *(*cookie)(void *buf_priv); 124 125 unsigned int (*num_users)(void *buf_priv); 126 127 int (*mmap)(void *buf_priv, struct vm_area_struct *vma); 128 }; 129 130 /** 131 * struct vb2_plane - plane information 132 * @mem_priv: private data with this plane 133 * @dbuf: dma_buf - shared buffer object 134 * @dbuf_mapped: flag to show whether dbuf is mapped or not 135 * @bytesused: number of bytes occupied by data in the plane (payload) 136 * @length: size of this plane (NOT the payload) in bytes 137 * @min_length: minimum required size of this plane (NOT the payload) in bytes. 138 * @length is always greater or equal to @min_length. 139 * @offset: when memory in the associated struct vb2_buffer is 140 * VB2_MEMORY_MMAP, equals the offset from the start of 141 * the device memory for this plane (or is a "cookie" that 142 * should be passed to mmap() called on the video node) 143 * @userptr: when memory is VB2_MEMORY_USERPTR, a userspace pointer 144 * pointing to this plane 145 * @fd: when memory is VB2_MEMORY_DMABUF, a userspace file 146 * descriptor associated with this plane 147 * @m: Union with memtype-specific data (@offset, @userptr or 148 * @fd). 149 * @data_offset: offset in the plane to the start of data; usually 0, 150 * unless there is a header in front of the data 151 * Should contain enough information to be able to cover all the fields 152 * of struct v4l2_plane at videodev2.h 153 */ 154 struct vb2_plane { 155 void *mem_priv; 156 struct dma_buf *dbuf; 157 unsigned int dbuf_mapped; 158 unsigned int bytesused; 159 unsigned int length; 160 unsigned int min_length; 161 union { 162 unsigned int offset; 163 unsigned long userptr; 164 int fd; 165 } m; 166 unsigned int data_offset; 167 }; 168 169 /** 170 * enum vb2_io_modes - queue access methods 171 * @VB2_MMAP: driver supports MMAP with streaming API 172 * @VB2_USERPTR: driver supports USERPTR with streaming API 173 * @VB2_READ: driver supports read() style access 174 * @VB2_WRITE: driver supports write() style access 175 * @VB2_DMABUF: driver supports DMABUF with streaming API 176 */ 177 enum vb2_io_modes { 178 VB2_MMAP = (1 << 0), 179 VB2_USERPTR = (1 << 1), 180 VB2_READ = (1 << 2), 181 VB2_WRITE = (1 << 3), 182 VB2_DMABUF = (1 << 4), 183 }; 184 185 /** 186 * enum vb2_buffer_state - current video buffer state 187 * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control 188 * @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf 189 * @VB2_BUF_STATE_PREPARED: buffer prepared in videobuf and by the driver 190 * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver 191 * @VB2_BUF_STATE_REQUEUEING: re-queue a buffer to the driver 192 * @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used 193 * in a hardware operation 194 * @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf, but 195 * not yet dequeued to userspace 196 * @VB2_BUF_STATE_ERROR: same as above, but the operation on the buffer 197 * has ended with an error, which will be reported 198 * to the userspace when it is dequeued 199 */ 200 enum vb2_buffer_state { 201 VB2_BUF_STATE_DEQUEUED, 202 VB2_BUF_STATE_PREPARING, 203 VB2_BUF_STATE_PREPARED, 204 VB2_BUF_STATE_QUEUED, 205 VB2_BUF_STATE_REQUEUEING, 206 VB2_BUF_STATE_ACTIVE, 207 VB2_BUF_STATE_DONE, 208 VB2_BUF_STATE_ERROR, 209 }; 210 211 struct vb2_queue; 212 213 /** 214 * struct vb2_buffer - represents a video buffer 215 * @vb2_queue: the queue to which this driver belongs 216 * @index: id number of the buffer 217 * @type: buffer type 218 * @memory: the method, in which the actual data is passed 219 * @num_planes: number of planes in the buffer 220 * on an internal driver queue 221 * @planes: private per-plane information; do not change 222 * @timestamp: frame timestamp in ns 223 */ 224 struct vb2_buffer { 225 struct vb2_queue *vb2_queue; 226 unsigned int index; 227 unsigned int type; 228 unsigned int memory; 229 unsigned int num_planes; 230 struct vb2_plane planes[VB2_MAX_PLANES]; 231 u64 timestamp; 232 233 /* private: internal use only 234 * 235 * state: current buffer state; do not change 236 * queued_entry: entry on the queued buffers list, which holds 237 * all buffers queued from userspace 238 * done_entry: entry on the list that stores all buffers ready 239 * to be dequeued to userspace 240 */ 241 enum vb2_buffer_state state; 242 243 struct list_head queued_entry; 244 struct list_head done_entry; 245 #ifdef CONFIG_VIDEO_ADV_DEBUG 246 /* 247 * Counters for how often these buffer-related ops are 248 * called. Used to check for unbalanced ops. 249 */ 250 u32 cnt_mem_alloc; 251 u32 cnt_mem_put; 252 u32 cnt_mem_get_dmabuf; 253 u32 cnt_mem_get_userptr; 254 u32 cnt_mem_put_userptr; 255 u32 cnt_mem_prepare; 256 u32 cnt_mem_finish; 257 u32 cnt_mem_attach_dmabuf; 258 u32 cnt_mem_detach_dmabuf; 259 u32 cnt_mem_map_dmabuf; 260 u32 cnt_mem_unmap_dmabuf; 261 u32 cnt_mem_vaddr; 262 u32 cnt_mem_cookie; 263 u32 cnt_mem_num_users; 264 u32 cnt_mem_mmap; 265 266 u32 cnt_buf_init; 267 u32 cnt_buf_prepare; 268 u32 cnt_buf_finish; 269 u32 cnt_buf_cleanup; 270 u32 cnt_buf_queue; 271 272 /* This counts the number of calls to vb2_buffer_done() */ 273 u32 cnt_buf_done; 274 #endif 275 }; 276 277 /** 278 * struct vb2_ops - driver-specific callbacks 279 * 280 * @queue_setup: called from %VIDIOC_REQBUFS and %VIDIOC_CREATE_BUFS 281 * handlers before memory allocation. It can be called 282 * twice: if the original number of requested buffers 283 * could not be allocated, then it will be called a 284 * second time with the actually allocated number of 285 * buffers to verify if that is OK. 286 * The driver should return the required number of buffers 287 * in \*num_buffers, the required number of planes per 288 * buffer in \*num_planes, the size of each plane should be 289 * set in the sizes\[\] array and optional per-plane 290 * allocator specific device in the alloc_devs\[\] array. 291 * When called from %VIDIOC_REQBUFS, \*num_planes == 0, the 292 * driver has to use the currently configured format to 293 * determine the plane sizes and \*num_buffers is the total 294 * number of buffers that are being allocated. When called 295 * from %VIDIOC_CREATE_BUFS, \*num_planes != 0 and it 296 * describes the requested number of planes and sizes\[\] 297 * contains the requested plane sizes. If either 298 * \*num_planes or the requested sizes are invalid callback 299 * must return %-EINVAL. In this case \*num_buffers are 300 * being allocated additionally to q->num_buffers. 301 * @wait_prepare: release any locks taken while calling vb2 functions; 302 * it is called before an ioctl needs to wait for a new 303 * buffer to arrive; required to avoid a deadlock in 304 * blocking access type. 305 * @wait_finish: reacquire all locks released in the previous callback; 306 * required to continue operation after sleeping while 307 * waiting for a new buffer to arrive. 308 * @buf_init: called once after allocating a buffer (in MMAP case) 309 * or after acquiring a new USERPTR buffer; drivers may 310 * perform additional buffer-related initialization; 311 * initialization failure (return != 0) will prevent 312 * queue setup from completing successfully; optional. 313 * @buf_prepare: called every time the buffer is queued from userspace 314 * and from the %VIDIOC_PREPARE_BUF ioctl; drivers may 315 * perform any initialization required before each 316 * hardware operation in this callback; drivers can 317 * access/modify the buffer here as it is still synced for 318 * the CPU; drivers that support %VIDIOC_CREATE_BUFS must 319 * also validate the buffer size; if an error is returned, 320 * the buffer will not be queued in driver; optional. 321 * @buf_finish: called before every dequeue of the buffer back to 322 * userspace; the buffer is synced for the CPU, so drivers 323 * can access/modify the buffer contents; drivers may 324 * perform any operations required before userspace 325 * accesses the buffer; optional. The buffer state can be 326 * one of the following: %DONE and %ERROR occur while 327 * streaming is in progress, and the %PREPARED state occurs 328 * when the queue has been canceled and all pending 329 * buffers are being returned to their default %DEQUEUED 330 * state. Typically you only have to do something if the 331 * state is %VB2_BUF_STATE_DONE, since in all other cases 332 * the buffer contents will be ignored anyway. 333 * @buf_cleanup: called once before the buffer is freed; drivers may 334 * perform any additional cleanup; optional. 335 * @start_streaming: called once to enter 'streaming' state; the driver may 336 * receive buffers with @buf_queue callback 337 * before @start_streaming is called; the driver gets the 338 * number of already queued buffers in count parameter; 339 * driver can return an error if hardware fails, in that 340 * case all buffers that have been already given by 341 * the @buf_queue callback are to be returned by the driver 342 * by calling @vb2_buffer_done\(%VB2_BUF_STATE_QUEUED\). 343 * If you need a minimum number of buffers before you can 344 * start streaming, then set @min_buffers_needed in the 345 * vb2_queue structure. If that is non-zero then 346 * start_streaming won't be called until at least that 347 * many buffers have been queued up by userspace. 348 * @stop_streaming: called when 'streaming' state must be disabled; driver 349 * should stop any DMA transactions or wait until they 350 * finish and give back all buffers it got from &buf_queue 351 * callback by calling @vb2_buffer_done\(\) with either 352 * %VB2_BUF_STATE_DONE or %VB2_BUF_STATE_ERROR; may use 353 * vb2_wait_for_all_buffers() function 354 * @buf_queue: passes buffer vb to the driver; driver may start 355 * hardware operation on this buffer; driver should give 356 * the buffer back by calling vb2_buffer_done() function; 357 * it is allways called after calling %VIDIOC_STREAMON ioctl; 358 * might be called before start_streaming callback if user 359 * pre-queued buffers before calling %VIDIOC_STREAMON. 360 */ 361 struct vb2_ops { 362 int (*queue_setup)(struct vb2_queue *q, 363 unsigned int *num_buffers, unsigned int *num_planes, 364 unsigned int sizes[], struct device *alloc_devs[]); 365 366 void (*wait_prepare)(struct vb2_queue *q); 367 void (*wait_finish)(struct vb2_queue *q); 368 369 int (*buf_init)(struct vb2_buffer *vb); 370 int (*buf_prepare)(struct vb2_buffer *vb); 371 void (*buf_finish)(struct vb2_buffer *vb); 372 void (*buf_cleanup)(struct vb2_buffer *vb); 373 374 int (*start_streaming)(struct vb2_queue *q, unsigned int count); 375 void (*stop_streaming)(struct vb2_queue *q); 376 377 void (*buf_queue)(struct vb2_buffer *vb); 378 }; 379 380 /** 381 * struct vb2_ops - driver-specific callbacks 382 * 383 * @verify_planes_array: Verify that a given user space structure contains 384 * enough planes for the buffer. This is called 385 * for each dequeued buffer. 386 * @fill_user_buffer: given a vb2_buffer fill in the userspace structure. 387 * For V4L2 this is a struct v4l2_buffer. 388 * @fill_vb2_buffer: given a userspace structure, fill in the vb2_buffer. 389 * If the userspace structure is invalid, then this op 390 * will return an error. 391 * @copy_timestamp: copy the timestamp from a userspace structure to 392 * the vb2_buffer struct. 393 */ 394 struct vb2_buf_ops { 395 int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb); 396 void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb); 397 int (*fill_vb2_buffer)(struct vb2_buffer *vb, const void *pb, 398 struct vb2_plane *planes); 399 void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb); 400 }; 401 402 /** 403 * struct vb2_queue - a videobuf queue 404 * 405 * @type: private buffer type whose content is defined by the vb2-core 406 * caller. For example, for V4L2, it should match 407 * the V4L2_BUF_TYPE_* in include/uapi/linux/videodev2.h 408 * @io_modes: supported io methods (see vb2_io_modes enum) 409 * @dev: device to use for the default allocation context if the driver 410 * doesn't fill in the @alloc_devs array. 411 * @dma_attrs: DMA attributes to use for the DMA. 412 * @fileio_read_once: report EOF after reading the first buffer 413 * @fileio_write_immediately: queue buffer after each write() call 414 * @allow_zero_bytesused: allow bytesused == 0 to be passed to the driver 415 * @quirk_poll_must_check_waiting_for_buffers: Return POLLERR at poll when QBUF 416 * has not been called. This is a vb1 idiom that has been adopted 417 * also by vb2. 418 * @lock: pointer to a mutex that protects the vb2_queue struct. The 419 * driver can set this to a mutex to let the v4l2 core serialize 420 * the queuing ioctls. If the driver wants to handle locking 421 * itself, then this should be set to NULL. This lock is not used 422 * by the videobuf2 core API. 423 * @owner: The filehandle that 'owns' the buffers, i.e. the filehandle 424 * that called reqbufs, create_buffers or started fileio. 425 * This field is not used by the videobuf2 core API, but it allows 426 * drivers to easily associate an owner filehandle with the queue. 427 * @ops: driver-specific callbacks 428 * @mem_ops: memory allocator specific callbacks 429 * @buf_ops: callbacks to deliver buffer information 430 * between user-space and kernel-space 431 * @drv_priv: driver private data 432 * @buf_struct_size: size of the driver-specific buffer structure; 433 * "0" indicates the driver doesn't want to use a custom buffer 434 * structure type. for example, sizeof(struct vb2_v4l2_buffer) 435 * will be used for v4l2. 436 * @timestamp_flags: Timestamp flags; V4L2_BUF_FLAG_TIMESTAMP_* and 437 * V4L2_BUF_FLAG_TSTAMP_SRC_* 438 * @gfp_flags: additional gfp flags used when allocating the buffers. 439 * Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32 440 * to force the buffer allocation to a specific memory zone. 441 * @min_buffers_needed: the minimum number of buffers needed before 442 * start_streaming() can be called. Used when a DMA engine 443 * cannot be started unless at least this number of buffers 444 * have been queued into the driver. 445 */ 446 /* 447 * Private elements (won't appear at the DocBook): 448 * @mmap_lock: private mutex used when buffers are allocated/freed/mmapped 449 * @memory: current memory type used 450 * @bufs: videobuf buffer structures 451 * @num_buffers: number of allocated/used buffers 452 * @queued_list: list of buffers currently queued from userspace 453 * @queued_count: number of buffers queued and ready for streaming. 454 * @owned_by_drv_count: number of buffers owned by the driver 455 * @done_list: list of buffers ready to be dequeued to userspace 456 * @done_lock: lock to protect done_list list 457 * @done_wq: waitqueue for processes waiting for buffers ready to be dequeued 458 * @alloc_devs: memory type/allocator-specific per-plane device 459 * @streaming: current streaming state 460 * @start_streaming_called: start_streaming() was called successfully and we 461 * started streaming. 462 * @error: a fatal error occurred on the queue 463 * @waiting_for_buffers: used in poll() to check if vb2 is still waiting for 464 * buffers. Only set for capture queues if qbuf has not yet been 465 * called since poll() needs to return POLLERR in that situation. 466 * @is_multiplanar: set if buffer type is multiplanar 467 * @is_output: set if buffer type is output 468 * @copy_timestamp: set if vb2-core should set timestamps 469 * @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the 470 * last decoded buffer was already dequeued. Set for capture queues 471 * when a buffer with the V4L2_BUF_FLAG_LAST is dequeued. 472 * @fileio: file io emulator internal data, used only if emulator is active 473 * @threadio: thread io internal data, used only if thread is active 474 */ 475 struct vb2_queue { 476 unsigned int type; 477 unsigned int io_modes; 478 struct device *dev; 479 unsigned long dma_attrs; 480 unsigned fileio_read_once:1; 481 unsigned fileio_write_immediately:1; 482 unsigned allow_zero_bytesused:1; 483 unsigned quirk_poll_must_check_waiting_for_buffers:1; 484 485 struct mutex *lock; 486 void *owner; 487 488 const struct vb2_ops *ops; 489 const struct vb2_mem_ops *mem_ops; 490 const struct vb2_buf_ops *buf_ops; 491 492 void *drv_priv; 493 unsigned int buf_struct_size; 494 u32 timestamp_flags; 495 gfp_t gfp_flags; 496 u32 min_buffers_needed; 497 498 /* private: internal use only */ 499 struct mutex mmap_lock; 500 unsigned int memory; 501 struct vb2_buffer *bufs[VB2_MAX_FRAME]; 502 unsigned int num_buffers; 503 504 struct list_head queued_list; 505 unsigned int queued_count; 506 507 atomic_t owned_by_drv_count; 508 struct list_head done_list; 509 spinlock_t done_lock; 510 wait_queue_head_t done_wq; 511 512 struct device *alloc_devs[VB2_MAX_PLANES]; 513 514 unsigned int streaming:1; 515 unsigned int start_streaming_called:1; 516 unsigned int error:1; 517 unsigned int waiting_for_buffers:1; 518 unsigned int is_multiplanar:1; 519 unsigned int is_output:1; 520 unsigned int copy_timestamp:1; 521 unsigned int last_buffer_dequeued:1; 522 523 struct vb2_fileio_data *fileio; 524 struct vb2_threadio_data *threadio; 525 526 #ifdef CONFIG_VIDEO_ADV_DEBUG 527 /* 528 * Counters for how often these queue-related ops are 529 * called. Used to check for unbalanced ops. 530 */ 531 u32 cnt_queue_setup; 532 u32 cnt_wait_prepare; 533 u32 cnt_wait_finish; 534 u32 cnt_start_streaming; 535 u32 cnt_stop_streaming; 536 #endif 537 }; 538 539 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); 540 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); 541 542 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state); 543 void vb2_discard_done(struct vb2_queue *q); 544 int vb2_wait_for_all_buffers(struct vb2_queue *q); 545 546 void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb); 547 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 548 unsigned int *count); 549 int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, 550 unsigned int *count, unsigned requested_planes, 551 const unsigned int requested_sizes[]); 552 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb); 553 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb); 554 int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, 555 bool nonblocking); 556 557 int vb2_core_streamon(struct vb2_queue *q, unsigned int type); 558 int vb2_core_streamoff(struct vb2_queue *q, unsigned int type); 559 560 int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, 561 unsigned int index, unsigned int plane, unsigned int flags); 562 563 int vb2_core_queue_init(struct vb2_queue *q); 564 void vb2_core_queue_release(struct vb2_queue *q); 565 566 void vb2_queue_error(struct vb2_queue *q); 567 568 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma); 569 #ifndef CONFIG_MMU 570 unsigned long vb2_get_unmapped_area(struct vb2_queue *q, 571 unsigned long addr, 572 unsigned long len, 573 unsigned long pgoff, 574 unsigned long flags); 575 #endif 576 unsigned int vb2_core_poll(struct vb2_queue *q, struct file *file, 577 poll_table *wait); 578 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, 579 loff_t *ppos, int nonblock); 580 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, 581 loff_t *ppos, int nonblock); 582 583 /* 584 * vb2_thread_fnc - callback function for use with vb2_thread 585 * 586 * This is called whenever a buffer is dequeued in the thread. 587 */ 588 typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv); 589 590 /** 591 * vb2_thread_start() - start a thread for the given queue. 592 * @q: videobuf queue 593 * @fnc: callback function 594 * @priv: priv pointer passed to the callback function 595 * @thread_name:the name of the thread. This will be prefixed with "vb2-". 596 * 597 * This starts a thread that will queue and dequeue until an error occurs 598 * or @vb2_thread_stop is called. 599 * 600 * This function should not be used for anything else but the videobuf2-dvb 601 * support. If you think you have another good use-case for this, then please 602 * contact the linux-media mailinglist first. 603 */ 604 int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, 605 const char *thread_name); 606 607 /** 608 * vb2_thread_stop() - stop the thread for the given queue. 609 * @q: videobuf queue 610 */ 611 int vb2_thread_stop(struct vb2_queue *q); 612 613 /** 614 * vb2_is_streaming() - return streaming status of the queue 615 * @q: videobuf queue 616 */ 617 static inline bool vb2_is_streaming(struct vb2_queue *q) 618 { 619 return q->streaming; 620 } 621 622 /** 623 * vb2_fileio_is_active() - return true if fileio is active. 624 * @q: videobuf queue 625 * 626 * This returns true if read() or write() is used to stream the data 627 * as opposed to stream I/O. This is almost never an important distinction, 628 * except in rare cases. One such case is that using read() or write() to 629 * stream a format using V4L2_FIELD_ALTERNATE is not allowed since there 630 * is no way you can pass the field information of each buffer to/from 631 * userspace. A driver that supports this field format should check for 632 * this in the queue_setup op and reject it if this function returns true. 633 */ 634 static inline bool vb2_fileio_is_active(struct vb2_queue *q) 635 { 636 return q->fileio; 637 } 638 639 /** 640 * vb2_is_busy() - return busy status of the queue 641 * @q: videobuf queue 642 * 643 * This function checks if queue has any buffers allocated. 644 */ 645 static inline bool vb2_is_busy(struct vb2_queue *q) 646 { 647 return (q->num_buffers > 0); 648 } 649 650 /** 651 * vb2_get_drv_priv() - return driver private data associated with the queue 652 * @q: videobuf queue 653 */ 654 static inline void *vb2_get_drv_priv(struct vb2_queue *q) 655 { 656 return q->drv_priv; 657 } 658 659 /** 660 * vb2_set_plane_payload() - set bytesused for the plane plane_no 661 * @vb: buffer for which plane payload should be set 662 * @plane_no: plane number for which payload should be set 663 * @size: payload in bytes 664 */ 665 static inline void vb2_set_plane_payload(struct vb2_buffer *vb, 666 unsigned int plane_no, unsigned long size) 667 { 668 if (plane_no < vb->num_planes) 669 vb->planes[plane_no].bytesused = size; 670 } 671 672 /** 673 * vb2_get_plane_payload() - get bytesused for the plane plane_no 674 * @vb: buffer for which plane payload should be set 675 * @plane_no: plane number for which payload should be set 676 */ 677 static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, 678 unsigned int plane_no) 679 { 680 if (plane_no < vb->num_planes) 681 return vb->planes[plane_no].bytesused; 682 return 0; 683 } 684 685 /** 686 * vb2_plane_size() - return plane size in bytes 687 * @vb: buffer for which plane size should be returned 688 * @plane_no: plane number for which size should be returned 689 */ 690 static inline unsigned long 691 vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no) 692 { 693 if (plane_no < vb->num_planes) 694 return vb->planes[plane_no].length; 695 return 0; 696 } 697 698 /** 699 * vb2_start_streaming_called() - return streaming status of driver 700 * @q: videobuf queue 701 */ 702 static inline bool vb2_start_streaming_called(struct vb2_queue *q) 703 { 704 return q->start_streaming_called; 705 } 706 707 /** 708 * vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue 709 * @q: videobuf queue 710 */ 711 static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) 712 { 713 q->last_buffer_dequeued = false; 714 } 715 716 /* 717 * The following functions are not part of the vb2 core API, but are useful 718 * functions for videobuf2-*. 719 */ 720 bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); 721 int vb2_verify_memory_type(struct vb2_queue *q, 722 enum vb2_memory memory, unsigned int type); 723 #endif /* _MEDIA_VIDEOBUF2_CORE_H */ 724