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