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 #include <linux/bitops.h> 20 #include <media/media-request.h> 21 22 #define VB2_MAX_FRAME (32) 23 #define VB2_MAX_PLANES (8) 24 25 /** 26 * enum vb2_memory - type of memory model used to make the buffers visible 27 * on userspace. 28 * 29 * @VB2_MEMORY_UNKNOWN: Buffer status is unknown or it is not used yet on 30 * userspace. 31 * @VB2_MEMORY_MMAP: The buffers are allocated by the Kernel and it is 32 * memory mapped via mmap() ioctl. This model is 33 * also used when the user is using the buffers via 34 * read() or write() system calls. 35 * @VB2_MEMORY_USERPTR: The buffers was allocated in userspace and it is 36 * memory mapped via mmap() ioctl. 37 * @VB2_MEMORY_DMABUF: The buffers are passed to userspace via DMA buffer. 38 */ 39 enum vb2_memory { 40 VB2_MEMORY_UNKNOWN = 0, 41 VB2_MEMORY_MMAP = 1, 42 VB2_MEMORY_USERPTR = 2, 43 VB2_MEMORY_DMABUF = 4, 44 }; 45 46 struct vb2_fileio_data; 47 struct vb2_threadio_data; 48 49 /** 50 * struct vb2_mem_ops - memory handling/memory allocator operations. 51 * @alloc: allocate video memory and, optionally, allocator private data, 52 * return ERR_PTR() on failure or a pointer to allocator private, 53 * per-buffer data on success; the returned private structure 54 * will then be passed as @buf_priv argument to other ops in this 55 * structure. Additional gfp_flags to use when allocating the 56 * are also passed to this operation. These flags are from the 57 * gfp_flags field of vb2_queue. 58 * @put: inform the allocator that the buffer will no longer be used; 59 * usually will result in the allocator freeing the buffer (if 60 * no other users of this buffer are present); the @buf_priv 61 * argument is the allocator private per-buffer structure 62 * previously returned from the alloc callback. 63 * @get_dmabuf: acquire userspace memory for a hardware operation; used for 64 * DMABUF memory types. 65 * @get_userptr: acquire userspace memory for a hardware operation; used for 66 * USERPTR memory types; vaddr is the address passed to the 67 * videobuf layer when queuing a video buffer of USERPTR type; 68 * should return an allocator private per-buffer structure 69 * associated with the buffer on success, ERR_PTR() on failure; 70 * the returned private structure will then be passed as @buf_priv 71 * argument to other ops in this structure. 72 * @put_userptr: inform the allocator that a USERPTR buffer will no longer 73 * be used. 74 * @attach_dmabuf: attach a shared &struct dma_buf for a hardware operation; 75 * used for DMABUF memory types; dev is the alloc device 76 * dbuf is the shared dma_buf; returns ERR_PTR() on failure; 77 * allocator private per-buffer structure on success; 78 * this needs to be used for further accesses to the buffer. 79 * @detach_dmabuf: inform the exporter of the buffer that the current DMABUF 80 * buffer is no longer used; the @buf_priv argument is the 81 * allocator private per-buffer structure previously returned 82 * from the attach_dmabuf callback. 83 * @map_dmabuf: request for access to the dmabuf from allocator; the allocator 84 * of dmabuf is informed that this driver is going to use the 85 * dmabuf. 86 * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified 87 * that this driver is done using the dmabuf for now. 88 * @prepare: called every time the buffer is passed from userspace to the 89 * driver, useful for cache synchronisation, optional. 90 * @finish: called every time the buffer is passed back from the driver 91 * to the userspace, also optional. 92 * @vaddr: return a kernel virtual address to a given memory buffer 93 * associated with the passed private structure or NULL if no 94 * such mapping exists. 95 * @cookie: return allocator specific cookie for a given memory buffer 96 * associated with the passed private structure or NULL if not 97 * available. 98 * @num_users: return the current number of users of a memory buffer; 99 * return 1 if the videobuf layer (or actually the driver using 100 * it) is the only user. 101 * @mmap: setup a userspace mapping for a given memory buffer under 102 * the provided virtual memory region. 103 * 104 * Those operations are used by the videobuf2 core to implement the memory 105 * handling/memory allocators for each type of supported streaming I/O method. 106 * 107 * .. note:: 108 * #) Required ops for USERPTR types: get_userptr, put_userptr. 109 * 110 * #) Required ops for MMAP types: alloc, put, num_users, mmap. 111 * 112 * #) Required ops for read/write access types: alloc, put, num_users, vaddr. 113 * 114 * #) Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, 115 * map_dmabuf, unmap_dmabuf. 116 */ 117 struct vb2_mem_ops { 118 void *(*alloc)(struct device *dev, unsigned long attrs, 119 unsigned long size, 120 enum dma_data_direction dma_dir, 121 gfp_t gfp_flags); 122 void (*put)(void *buf_priv); 123 struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags); 124 125 void *(*get_userptr)(struct device *dev, unsigned long vaddr, 126 unsigned long size, 127 enum dma_data_direction dma_dir); 128 void (*put_userptr)(void *buf_priv); 129 130 void (*prepare)(void *buf_priv); 131 void (*finish)(void *buf_priv); 132 133 void *(*attach_dmabuf)(struct device *dev, 134 struct dma_buf *dbuf, 135 unsigned long size, 136 enum dma_data_direction dma_dir); 137 void (*detach_dmabuf)(void *buf_priv); 138 int (*map_dmabuf)(void *buf_priv); 139 void (*unmap_dmabuf)(void *buf_priv); 140 141 void *(*vaddr)(void *buf_priv); 142 void *(*cookie)(void *buf_priv); 143 144 unsigned int (*num_users)(void *buf_priv); 145 146 int (*mmap)(void *buf_priv, struct vm_area_struct *vma); 147 }; 148 149 /** 150 * struct vb2_plane - plane information. 151 * @mem_priv: private data with this plane. 152 * @dbuf: dma_buf - shared buffer object. 153 * @dbuf_mapped: flag to show whether dbuf is mapped or not 154 * @bytesused: number of bytes occupied by data in the plane (payload). 155 * @length: size of this plane (NOT the payload) in bytes. 156 * @min_length: minimum required size of this plane (NOT the payload) in bytes. 157 * @length is always greater or equal to @min_length. 158 * @m: Union with memtype-specific data. 159 * @m.offset: when memory in the associated struct vb2_buffer is 160 * %VB2_MEMORY_MMAP, equals the offset from the start of 161 * the device memory for this plane (or is a "cookie" that 162 * should be passed to mmap() called on the video node). 163 * @m.userptr: when memory is %VB2_MEMORY_USERPTR, a userspace pointer 164 * pointing to this plane. 165 * @m.fd: when memory is %VB2_MEMORY_DMABUF, a userspace file 166 * descriptor associated with this plane. 167 * @data_offset: offset in the plane to the start of data; usually 0, 168 * unless there is a header in front of the data. 169 * 170 * Should contain enough information to be able to cover all the fields 171 * of &struct v4l2_plane at videodev2.h. 172 */ 173 struct vb2_plane { 174 void *mem_priv; 175 struct dma_buf *dbuf; 176 unsigned int dbuf_mapped; 177 unsigned int bytesused; 178 unsigned int length; 179 unsigned int min_length; 180 union { 181 unsigned int offset; 182 unsigned long userptr; 183 int fd; 184 } m; 185 unsigned int data_offset; 186 }; 187 188 /** 189 * enum vb2_io_modes - queue access methods. 190 * @VB2_MMAP: driver supports MMAP with streaming API. 191 * @VB2_USERPTR: driver supports USERPTR with streaming API. 192 * @VB2_READ: driver supports read() style access. 193 * @VB2_WRITE: driver supports write() style access. 194 * @VB2_DMABUF: driver supports DMABUF with streaming API. 195 */ 196 enum vb2_io_modes { 197 VB2_MMAP = BIT(0), 198 VB2_USERPTR = BIT(1), 199 VB2_READ = BIT(2), 200 VB2_WRITE = BIT(3), 201 VB2_DMABUF = BIT(4), 202 }; 203 204 /** 205 * enum vb2_buffer_state - current video buffer state. 206 * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control. 207 * @VB2_BUF_STATE_IN_REQUEST: buffer is queued in media request. 208 * @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf. 209 * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver. 210 * @VB2_BUF_STATE_REQUEUEING: re-queue a buffer to the driver. 211 * @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used 212 * in a hardware operation. 213 * @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf, but 214 * not yet dequeued to userspace. 215 * @VB2_BUF_STATE_ERROR: same as above, but the operation on the buffer 216 * has ended with an error, which will be reported 217 * to the userspace when it is dequeued. 218 */ 219 enum vb2_buffer_state { 220 VB2_BUF_STATE_DEQUEUED, 221 VB2_BUF_STATE_IN_REQUEST, 222 VB2_BUF_STATE_PREPARING, 223 VB2_BUF_STATE_QUEUED, 224 VB2_BUF_STATE_REQUEUEING, 225 VB2_BUF_STATE_ACTIVE, 226 VB2_BUF_STATE_DONE, 227 VB2_BUF_STATE_ERROR, 228 }; 229 230 struct vb2_queue; 231 232 /** 233 * struct vb2_buffer - represents a video buffer. 234 * @vb2_queue: pointer to &struct vb2_queue with the queue to 235 * which this driver belongs. 236 * @index: id number of the buffer. 237 * @type: buffer type. 238 * @memory: the method, in which the actual data is passed. 239 * @num_planes: number of planes in the buffer 240 * on an internal driver queue. 241 * @timestamp: frame timestamp in ns. 242 * @request: the request this buffer is associated with. 243 * @req_obj: used to bind this buffer to a request. This 244 * request object has a refcount. 245 */ 246 struct vb2_buffer { 247 struct vb2_queue *vb2_queue; 248 unsigned int index; 249 unsigned int type; 250 unsigned int memory; 251 unsigned int num_planes; 252 u64 timestamp; 253 struct media_request *request; 254 struct media_request_object req_obj; 255 256 /* private: internal use only 257 * 258 * state: current buffer state; do not change 259 * synced: this buffer has been synced for DMA, i.e. the 260 * 'prepare' memop was called. It is cleared again 261 * after the 'finish' memop is called. 262 * prepared: this buffer has been prepared, i.e. the 263 * buf_prepare op was called. It is cleared again 264 * after the 'buf_finish' op is called. 265 * queued_entry: entry on the queued buffers list, which holds 266 * all buffers queued from userspace 267 * done_entry: entry on the list that stores all buffers ready 268 * to be dequeued to userspace 269 * vb2_plane: per-plane information; do not change 270 */ 271 enum vb2_buffer_state state; 272 bool synced; 273 bool prepared; 274 275 struct vb2_plane planes[VB2_MAX_PLANES]; 276 struct list_head queued_entry; 277 struct list_head done_entry; 278 #ifdef CONFIG_VIDEO_ADV_DEBUG 279 /* 280 * Counters for how often these buffer-related ops are 281 * called. Used to check for unbalanced ops. 282 */ 283 u32 cnt_mem_alloc; 284 u32 cnt_mem_put; 285 u32 cnt_mem_get_dmabuf; 286 u32 cnt_mem_get_userptr; 287 u32 cnt_mem_put_userptr; 288 u32 cnt_mem_prepare; 289 u32 cnt_mem_finish; 290 u32 cnt_mem_attach_dmabuf; 291 u32 cnt_mem_detach_dmabuf; 292 u32 cnt_mem_map_dmabuf; 293 u32 cnt_mem_unmap_dmabuf; 294 u32 cnt_mem_vaddr; 295 u32 cnt_mem_cookie; 296 u32 cnt_mem_num_users; 297 u32 cnt_mem_mmap; 298 299 u32 cnt_buf_init; 300 u32 cnt_buf_prepare; 301 u32 cnt_buf_finish; 302 u32 cnt_buf_cleanup; 303 u32 cnt_buf_queue; 304 u32 cnt_buf_request_complete; 305 306 /* This counts the number of calls to vb2_buffer_done() */ 307 u32 cnt_buf_done; 308 #endif 309 }; 310 311 /** 312 * struct vb2_ops - driver-specific callbacks. 313 * 314 * These operations are not called from interrupt context except where 315 * mentioned specifically. 316 * 317 * @queue_setup: called from VIDIOC_REQBUFS() and VIDIOC_CREATE_BUFS() 318 * handlers before memory allocation. It can be called 319 * twice: if the original number of requested buffers 320 * could not be allocated, then it will be called a 321 * second time with the actually allocated number of 322 * buffers to verify if that is OK. 323 * The driver should return the required number of buffers 324 * in \*num_buffers, the required number of planes per 325 * buffer in \*num_planes, the size of each plane should be 326 * set in the sizes\[\] array and optional per-plane 327 * allocator specific device in the alloc_devs\[\] array. 328 * When called from VIDIOC_REQBUFS(), \*num_planes == 0, 329 * the driver has to use the currently configured format to 330 * determine the plane sizes and \*num_buffers is the total 331 * number of buffers that are being allocated. When called 332 * from VIDIOC_CREATE_BUFS(), \*num_planes != 0 and it 333 * describes the requested number of planes and sizes\[\] 334 * contains the requested plane sizes. In this case 335 * \*num_buffers are being allocated additionally to 336 * q->num_buffers. If either \*num_planes or the requested 337 * sizes are invalid callback must return %-EINVAL. 338 * @wait_prepare: release any locks taken while calling vb2 functions; 339 * it is called before an ioctl needs to wait for a new 340 * buffer to arrive; required to avoid a deadlock in 341 * blocking access type. 342 * @wait_finish: reacquire all locks released in the previous callback; 343 * required to continue operation after sleeping while 344 * waiting for a new buffer to arrive. 345 * @buf_init: called once after allocating a buffer (in MMAP case) 346 * or after acquiring a new USERPTR buffer; drivers may 347 * perform additional buffer-related initialization; 348 * initialization failure (return != 0) will prevent 349 * queue setup from completing successfully; optional. 350 * @buf_prepare: called every time the buffer is queued from userspace 351 * and from the VIDIOC_PREPARE_BUF() ioctl; drivers may 352 * perform any initialization required before each 353 * hardware operation in this callback; drivers can 354 * access/modify the buffer here as it is still synced for 355 * the CPU; drivers that support VIDIOC_CREATE_BUFS() must 356 * also validate the buffer size; if an error is returned, 357 * the buffer will not be queued in driver; optional. 358 * @buf_finish: called before every dequeue of the buffer back to 359 * userspace; the buffer is synced for the CPU, so drivers 360 * can access/modify the buffer contents; drivers may 361 * perform any operations required before userspace 362 * accesses the buffer; optional. The buffer state can be 363 * one of the following: %DONE and %ERROR occur while 364 * streaming is in progress, and the %PREPARED state occurs 365 * when the queue has been canceled and all pending 366 * buffers are being returned to their default %DEQUEUED 367 * state. Typically you only have to do something if the 368 * state is %VB2_BUF_STATE_DONE, since in all other cases 369 * the buffer contents will be ignored anyway. 370 * @buf_cleanup: called once before the buffer is freed; drivers may 371 * perform any additional cleanup; optional. 372 * @start_streaming: called once to enter 'streaming' state; the driver may 373 * receive buffers with @buf_queue callback 374 * before @start_streaming is called; the driver gets the 375 * number of already queued buffers in count parameter; 376 * driver can return an error if hardware fails, in that 377 * case all buffers that have been already given by 378 * the @buf_queue callback are to be returned by the driver 379 * by calling vb2_buffer_done() with %VB2_BUF_STATE_QUEUED 380 * or %VB2_BUF_STATE_REQUEUEING. If you need a minimum 381 * number of buffers before you can start streaming, then 382 * set &vb2_queue->min_buffers_needed. If that is non-zero 383 * then @start_streaming won't be called until at least 384 * that many buffers have been queued up by userspace. 385 * @stop_streaming: called when 'streaming' state must be disabled; driver 386 * should stop any DMA transactions or wait until they 387 * finish and give back all buffers it got from &buf_queue 388 * callback by calling vb2_buffer_done() with either 389 * %VB2_BUF_STATE_DONE or %VB2_BUF_STATE_ERROR; may use 390 * vb2_wait_for_all_buffers() function 391 * @buf_queue: passes buffer vb to the driver; driver may start 392 * hardware operation on this buffer; driver should give 393 * the buffer back by calling vb2_buffer_done() function; 394 * it is allways called after calling VIDIOC_STREAMON() 395 * ioctl; might be called before @start_streaming callback 396 * if user pre-queued buffers before calling 397 * VIDIOC_STREAMON(). 398 * @buf_request_complete: a buffer that was never queued to the driver but is 399 * associated with a queued request was canceled. 400 * The driver will have to mark associated objects in the 401 * request as completed; required if requests are 402 * supported. 403 */ 404 struct vb2_ops { 405 int (*queue_setup)(struct vb2_queue *q, 406 unsigned int *num_buffers, unsigned int *num_planes, 407 unsigned int sizes[], struct device *alloc_devs[]); 408 409 void (*wait_prepare)(struct vb2_queue *q); 410 void (*wait_finish)(struct vb2_queue *q); 411 412 int (*buf_init)(struct vb2_buffer *vb); 413 int (*buf_prepare)(struct vb2_buffer *vb); 414 void (*buf_finish)(struct vb2_buffer *vb); 415 void (*buf_cleanup)(struct vb2_buffer *vb); 416 417 int (*start_streaming)(struct vb2_queue *q, unsigned int count); 418 void (*stop_streaming)(struct vb2_queue *q); 419 420 void (*buf_queue)(struct vb2_buffer *vb); 421 422 void (*buf_request_complete)(struct vb2_buffer *vb); 423 }; 424 425 /** 426 * struct vb2_buf_ops - driver-specific callbacks. 427 * 428 * @verify_planes_array: Verify that a given user space structure contains 429 * enough planes for the buffer. This is called 430 * for each dequeued buffer. 431 * @init_buffer: given a &vb2_buffer initialize the extra data after 432 * struct vb2_buffer. 433 * For V4L2 this is a &struct vb2_v4l2_buffer. 434 * @fill_user_buffer: given a &vb2_buffer fill in the userspace structure. 435 * For V4L2 this is a &struct v4l2_buffer. 436 * @fill_vb2_buffer: given a userspace structure, fill in the &vb2_buffer. 437 * If the userspace structure is invalid, then this op 438 * will return an error. 439 * @copy_timestamp: copy the timestamp from a userspace structure to 440 * the &struct vb2_buffer. 441 */ 442 struct vb2_buf_ops { 443 int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb); 444 void (*init_buffer)(struct vb2_buffer *vb); 445 void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb); 446 int (*fill_vb2_buffer)(struct vb2_buffer *vb, struct vb2_plane *planes); 447 void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb); 448 }; 449 450 /** 451 * struct vb2_queue - a videobuf queue. 452 * 453 * @type: private buffer type whose content is defined by the vb2-core 454 * caller. For example, for V4L2, it should match 455 * the types defined on &enum v4l2_buf_type. 456 * @io_modes: supported io methods (see &enum vb2_io_modes). 457 * @alloc_devs: &struct device memory type/allocator-specific per-plane device 458 * @dev: device to use for the default allocation context if the driver 459 * doesn't fill in the @alloc_devs array. 460 * @dma_attrs: DMA attributes to use for the DMA. 461 * @bidirectional: when this flag is set the DMA direction for the buffers of 462 * this queue will be overridden with %DMA_BIDIRECTIONAL direction. 463 * This is useful in cases where the hardware (firmware) writes to 464 * a buffer which is mapped as read (%DMA_TO_DEVICE), or reads from 465 * buffer which is mapped for write (%DMA_FROM_DEVICE) in order 466 * to satisfy some internal hardware restrictions or adds a padding 467 * needed by the processing algorithm. In case the DMA mapping is 468 * not bidirectional but the hardware (firmware) trying to access 469 * the buffer (in the opposite direction) this could lead to an 470 * IOMMU protection faults. 471 * @fileio_read_once: report EOF after reading the first buffer 472 * @fileio_write_immediately: queue buffer after each write() call 473 * @allow_zero_bytesused: allow bytesused == 0 to be passed to the driver 474 * @quirk_poll_must_check_waiting_for_buffers: Return %EPOLLERR at poll when QBUF 475 * has not been called. This is a vb1 idiom that has been adopted 476 * also by vb2. 477 * @supports_requests: this queue supports the Request API. 478 * @uses_qbuf: qbuf was used directly for this queue. Set to 1 the first 479 * time this is called. Set to 0 when the queue is canceled. 480 * If this is 1, then you cannot queue buffers from a request. 481 * @uses_requests: requests are used for this queue. Set to 1 the first time 482 * a request is queued. Set to 0 when the queue is canceled. 483 * If this is 1, then you cannot queue buffers directly. 484 * @lock: pointer to a mutex that protects the &struct vb2_queue. The 485 * driver can set this to a mutex to let the v4l2 core serialize 486 * the queuing ioctls. If the driver wants to handle locking 487 * itself, then this should be set to NULL. This lock is not used 488 * by the videobuf2 core API. 489 * @owner: The filehandle that 'owns' the buffers, i.e. the filehandle 490 * that called reqbufs, create_buffers or started fileio. 491 * This field is not used by the videobuf2 core API, but it allows 492 * drivers to easily associate an owner filehandle with the queue. 493 * @ops: driver-specific callbacks 494 * @mem_ops: memory allocator specific callbacks 495 * @buf_ops: callbacks to deliver buffer information. 496 * between user-space and kernel-space. 497 * @drv_priv: driver private data. 498 * @buf_struct_size: size of the driver-specific buffer structure; 499 * "0" indicates the driver doesn't want to use a custom buffer 500 * structure type. for example, ``sizeof(struct vb2_v4l2_buffer)`` 501 * will be used for v4l2. 502 * @timestamp_flags: Timestamp flags; ``V4L2_BUF_FLAG_TIMESTAMP_*`` and 503 * ``V4L2_BUF_FLAG_TSTAMP_SRC_*`` 504 * @gfp_flags: additional gfp flags used when allocating the buffers. 505 * Typically this is 0, but it may be e.g. %GFP_DMA or %__GFP_DMA32 506 * to force the buffer allocation to a specific memory zone. 507 * @min_buffers_needed: the minimum number of buffers needed before 508 * @start_streaming can be called. Used when a DMA engine 509 * cannot be started unless at least this number of buffers 510 * have been queued into the driver. 511 */ 512 /* 513 * Private elements (won't appear at the uAPI book): 514 * @mmap_lock: private mutex used when buffers are allocated/freed/mmapped 515 * @memory: current memory type used 516 * @dma_dir: DMA mapping direction. 517 * @bufs: videobuf buffer structures 518 * @num_buffers: number of allocated/used buffers 519 * @queued_list: list of buffers currently queued from userspace 520 * @queued_count: number of buffers queued and ready for streaming. 521 * @owned_by_drv_count: number of buffers owned by the driver 522 * @done_list: list of buffers ready to be dequeued to userspace 523 * @done_lock: lock to protect done_list list 524 * @done_wq: waitqueue for processes waiting for buffers ready to be dequeued 525 * @streaming: current streaming state 526 * @start_streaming_called: @start_streaming was called successfully and we 527 * started streaming. 528 * @error: a fatal error occurred on the queue 529 * @waiting_for_buffers: used in poll() to check if vb2 is still waiting for 530 * buffers. Only set for capture queues if qbuf has not yet been 531 * called since poll() needs to return %EPOLLERR in that situation. 532 * @is_multiplanar: set if buffer type is multiplanar 533 * @is_output: set if buffer type is output 534 * @copy_timestamp: set if vb2-core should set timestamps 535 * @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the 536 * last decoded buffer was already dequeued. Set for capture queues 537 * when a buffer with the %V4L2_BUF_FLAG_LAST is dequeued. 538 * @fileio: file io emulator internal data, used only if emulator is active 539 * @threadio: thread io internal data, used only if thread is active 540 */ 541 struct vb2_queue { 542 unsigned int type; 543 unsigned int io_modes; 544 struct device *dev; 545 unsigned long dma_attrs; 546 unsigned bidirectional:1; 547 unsigned fileio_read_once:1; 548 unsigned fileio_write_immediately:1; 549 unsigned allow_zero_bytesused:1; 550 unsigned quirk_poll_must_check_waiting_for_buffers:1; 551 unsigned supports_requests:1; 552 unsigned uses_qbuf:1; 553 unsigned uses_requests:1; 554 555 struct mutex *lock; 556 void *owner; 557 558 const struct vb2_ops *ops; 559 const struct vb2_mem_ops *mem_ops; 560 const struct vb2_buf_ops *buf_ops; 561 562 void *drv_priv; 563 unsigned int buf_struct_size; 564 u32 timestamp_flags; 565 gfp_t gfp_flags; 566 u32 min_buffers_needed; 567 568 struct device *alloc_devs[VB2_MAX_PLANES]; 569 570 /* private: internal use only */ 571 struct mutex mmap_lock; 572 unsigned int memory; 573 enum dma_data_direction dma_dir; 574 struct vb2_buffer *bufs[VB2_MAX_FRAME]; 575 unsigned int num_buffers; 576 577 struct list_head queued_list; 578 unsigned int queued_count; 579 580 atomic_t owned_by_drv_count; 581 struct list_head done_list; 582 spinlock_t done_lock; 583 wait_queue_head_t done_wq; 584 585 unsigned int streaming:1; 586 unsigned int start_streaming_called:1; 587 unsigned int error:1; 588 unsigned int waiting_for_buffers:1; 589 unsigned int is_multiplanar:1; 590 unsigned int is_output:1; 591 unsigned int copy_timestamp:1; 592 unsigned int last_buffer_dequeued:1; 593 594 struct vb2_fileio_data *fileio; 595 struct vb2_threadio_data *threadio; 596 597 #ifdef CONFIG_VIDEO_ADV_DEBUG 598 /* 599 * Counters for how often these queue-related ops are 600 * called. Used to check for unbalanced ops. 601 */ 602 u32 cnt_queue_setup; 603 u32 cnt_wait_prepare; 604 u32 cnt_wait_finish; 605 u32 cnt_start_streaming; 606 u32 cnt_stop_streaming; 607 #endif 608 }; 609 610 /** 611 * vb2_plane_vaddr() - Return a kernel virtual address of a given plane. 612 * @vb: pointer to &struct vb2_buffer to which the plane in 613 * question belongs to. 614 * @plane_no: plane number for which the address is to be returned. 615 * 616 * This function returns a kernel virtual address of a given plane if 617 * such a mapping exist, NULL otherwise. 618 */ 619 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); 620 621 /** 622 * vb2_plane_cookie() - Return allocator specific cookie for the given plane. 623 * @vb: pointer to &struct vb2_buffer to which the plane in 624 * question belongs to. 625 * @plane_no: plane number for which the cookie is to be returned. 626 * 627 * This function returns an allocator specific cookie for a given plane if 628 * available, NULL otherwise. The allocator should provide some simple static 629 * inline function, which would convert this cookie to the allocator specific 630 * type that can be used directly by the driver to access the buffer. This can 631 * be for example physical address, pointer to scatter list or IOMMU mapping. 632 */ 633 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); 634 635 /** 636 * vb2_buffer_done() - inform videobuf that an operation on a buffer 637 * is finished. 638 * @vb: pointer to &struct vb2_buffer to be used. 639 * @state: state of the buffer, as defined by &enum vb2_buffer_state. 640 * Either %VB2_BUF_STATE_DONE if the operation finished 641 * successfully, %VB2_BUF_STATE_ERROR if the operation finished 642 * with an error or any of %VB2_BUF_STATE_QUEUED or 643 * %VB2_BUF_STATE_REQUEUEING if the driver wants to 644 * requeue buffers (see below). 645 * 646 * This function should be called by the driver after a hardware operation on 647 * a buffer is finished and the buffer may be returned to userspace. The driver 648 * cannot use this buffer anymore until it is queued back to it by videobuf 649 * by the means of &vb2_ops->buf_queue callback. Only buffers previously queued 650 * to the driver by &vb2_ops->buf_queue can be passed to this function. 651 * 652 * While streaming a buffer can only be returned in state DONE or ERROR. 653 * The &vb2_ops->start_streaming op can also return them in case the DMA engine 654 * cannot be started for some reason. In that case the buffers should be 655 * returned with state QUEUED or REQUEUEING to put them back into the queue. 656 * 657 * %VB2_BUF_STATE_REQUEUEING is like %VB2_BUF_STATE_QUEUED, but it also calls 658 * &vb2_ops->buf_queue to queue buffers back to the driver. Note that calling 659 * vb2_buffer_done(..., VB2_BUF_STATE_REQUEUEING) from interrupt context will 660 * result in &vb2_ops->buf_queue being called in interrupt context as well. 661 */ 662 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state); 663 664 /** 665 * vb2_discard_done() - discard all buffers marked as DONE. 666 * @q: pointer to &struct vb2_queue with videobuf2 queue. 667 * 668 * This function is intended to be used with suspend/resume operations. It 669 * discards all 'done' buffers as they would be too old to be requested after 670 * resume. 671 * 672 * Drivers must stop the hardware and synchronize with interrupt handlers and/or 673 * delayed works before calling this function to make sure no buffer will be 674 * touched by the driver and/or hardware. 675 */ 676 void vb2_discard_done(struct vb2_queue *q); 677 678 /** 679 * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2. 680 * @q: pointer to &struct vb2_queue with videobuf2 queue. 681 * 682 * This function will wait until all buffers that have been given to the driver 683 * by &vb2_ops->buf_queue are given back to vb2 with vb2_buffer_done(). It 684 * doesn't call &vb2_ops->wait_prepare/&vb2_ops->wait_finish pair. 685 * It is intended to be called with all locks taken, for example from 686 * &vb2_ops->stop_streaming callback. 687 */ 688 int vb2_wait_for_all_buffers(struct vb2_queue *q); 689 690 /** 691 * vb2_core_querybuf() - query video buffer information. 692 * @q: pointer to &struct vb2_queue with videobuf2 queue. 693 * @index: id number of the buffer. 694 * @pb: buffer struct passed from userspace. 695 * 696 * Videobuf2 core helper to implement VIDIOC_QUERYBUF() operation. It is called 697 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 698 * 699 * The passed buffer should have been verified. 700 * 701 * This function fills the relevant information for the userspace. 702 * 703 * Return: returns zero on success; an error code otherwise. 704 */ 705 void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb); 706 707 /** 708 * vb2_core_reqbufs() - Initiate streaming. 709 * @q: pointer to &struct vb2_queue with videobuf2 queue. 710 * @memory: memory type, as defined by &enum vb2_memory. 711 * @count: requested buffer count. 712 * 713 * Videobuf2 core helper to implement VIDIOC_REQBUF() operation. It is called 714 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 715 * 716 * This function: 717 * 718 * #) verifies streaming parameters passed from the userspace; 719 * #) sets up the queue; 720 * #) negotiates number of buffers and planes per buffer with the driver 721 * to be used during streaming; 722 * #) allocates internal buffer structures (&struct vb2_buffer), according to 723 * the agreed parameters; 724 * #) for MMAP memory type, allocates actual video memory, using the 725 * memory handling/allocation routines provided during queue initialization. 726 * 727 * If req->count is 0, all the memory will be freed instead. 728 * 729 * If the queue has been allocated previously by a previous vb2_core_reqbufs() 730 * call and the queue is not busy, memory will be reallocated. 731 * 732 * Return: returns zero on success; an error code otherwise. 733 */ 734 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 735 unsigned int *count); 736 737 /** 738 * vb2_core_create_bufs() - Allocate buffers and any required auxiliary structs 739 * @q: pointer to &struct vb2_queue with videobuf2 queue. 740 * @memory: memory type, as defined by &enum vb2_memory. 741 * @count: requested buffer count. 742 * @requested_planes: number of planes requested. 743 * @requested_sizes: array with the size of the planes. 744 * 745 * Videobuf2 core helper to implement VIDIOC_CREATE_BUFS() operation. It is 746 * called internally by VB2 by an API-specific handler, like 747 * ``videobuf2-v4l2.h``. 748 * 749 * This function: 750 * 751 * #) verifies parameter sanity; 752 * #) calls the &vb2_ops->queue_setup queue operation; 753 * #) performs any necessary memory allocations. 754 * 755 * Return: returns zero on success; an error code otherwise. 756 */ 757 int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, 758 unsigned int *count, unsigned int requested_planes, 759 const unsigned int requested_sizes[]); 760 761 /** 762 * vb2_core_prepare_buf() - Pass ownership of a buffer from userspace 763 * to the kernel. 764 * @q: pointer to &struct vb2_queue with videobuf2 queue. 765 * @index: id number of the buffer. 766 * @pb: buffer structure passed from userspace to 767 * &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver. 768 * 769 * Videobuf2 core helper to implement VIDIOC_PREPARE_BUF() operation. It is 770 * called internally by VB2 by an API-specific handler, like 771 * ``videobuf2-v4l2.h``. 772 * 773 * The passed buffer should have been verified. 774 * 775 * This function calls vb2_ops->buf_prepare callback in the driver 776 * (if provided), in which driver-specific buffer initialization can 777 * be performed. 778 * 779 * Return: returns zero on success; an error code otherwise. 780 */ 781 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb); 782 783 /** 784 * vb2_core_qbuf() - Queue a buffer from userspace 785 * 786 * @q: pointer to &struct vb2_queue with videobuf2 queue. 787 * @index: id number of the buffer 788 * @pb: buffer structure passed from userspace to 789 * v4l2_ioctl_ops->vidioc_qbuf handler in driver 790 * @req: pointer to &struct media_request, may be NULL. 791 * 792 * Videobuf2 core helper to implement VIDIOC_QBUF() operation. It is called 793 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 794 * 795 * This function: 796 * 797 * #) If @req is non-NULL, then the buffer will be bound to this 798 * media request and it returns. The buffer will be prepared and 799 * queued to the driver (i.e. the next two steps) when the request 800 * itself is queued. 801 * #) if necessary, calls &vb2_ops->buf_prepare callback in the driver 802 * (if provided), in which driver-specific buffer initialization can 803 * be performed; 804 * #) if streaming is on, queues the buffer in driver by the means of 805 * &vb2_ops->buf_queue callback for processing. 806 * 807 * Return: returns zero on success; an error code otherwise. 808 */ 809 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, 810 struct media_request *req); 811 812 /** 813 * vb2_core_dqbuf() - Dequeue a buffer to the userspace 814 * @q: pointer to &struct vb2_queue with videobuf2 queue 815 * @pindex: pointer to the buffer index. May be NULL 816 * @pb: buffer structure passed from userspace to 817 * v4l2_ioctl_ops->vidioc_dqbuf handler in driver. 818 * @nonblocking: if true, this call will not sleep waiting for a buffer if no 819 * buffers ready for dequeuing are present. Normally the driver 820 * would be passing (file->f_flags & O_NONBLOCK) here. 821 * 822 * Videobuf2 core helper to implement VIDIOC_DQBUF() operation. It is called 823 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 824 * 825 * This function: 826 * 827 * #) calls buf_finish callback in the driver (if provided), in which 828 * driver can perform any additional operations that may be required before 829 * returning the buffer to userspace, such as cache sync, 830 * #) the buffer struct members are filled with relevant information for 831 * the userspace. 832 * 833 * Return: returns zero on success; an error code otherwise. 834 */ 835 int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, 836 bool nonblocking); 837 838 /** 839 * vb2_core_streamon() - Implements VB2 stream ON logic 840 * 841 * @q: pointer to &struct vb2_queue with videobuf2 queue 842 * @type: type of the queue to be started. 843 * For V4L2, this is defined by &enum v4l2_buf_type type. 844 * 845 * Videobuf2 core helper to implement VIDIOC_STREAMON() operation. It is called 846 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 847 * 848 * Return: returns zero on success; an error code otherwise. 849 */ 850 int vb2_core_streamon(struct vb2_queue *q, unsigned int type); 851 852 /** 853 * vb2_core_streamoff() - Implements VB2 stream OFF logic 854 * 855 * @q: pointer to &struct vb2_queue with videobuf2 queue 856 * @type: type of the queue to be started. 857 * For V4L2, this is defined by &enum v4l2_buf_type type. 858 * 859 * Videobuf2 core helper to implement VIDIOC_STREAMOFF() operation. It is 860 * called internally by VB2 by an API-specific handler, like 861 * ``videobuf2-v4l2.h``. 862 * 863 * Return: returns zero on success; an error code otherwise. 864 */ 865 int vb2_core_streamoff(struct vb2_queue *q, unsigned int type); 866 867 /** 868 * vb2_core_expbuf() - Export a buffer as a file descriptor. 869 * @q: pointer to &struct vb2_queue with videobuf2 queue. 870 * @fd: pointer to the file descriptor associated with DMABUF 871 * (set by driver). 872 * @type: buffer type. 873 * @index: id number of the buffer. 874 * @plane: index of the plane to be exported, 0 for single plane queues 875 * @flags: file flags for newly created file, as defined at 876 * include/uapi/asm-generic/fcntl.h. 877 * Currently, the only used flag is %O_CLOEXEC. 878 * is supported, refer to manual of open syscall for more details. 879 * 880 * 881 * Videobuf2 core helper to implement VIDIOC_EXPBUF() operation. It is called 882 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 883 * 884 * Return: returns zero on success; an error code otherwise. 885 */ 886 int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, 887 unsigned int index, unsigned int plane, unsigned int flags); 888 889 /** 890 * vb2_core_queue_init() - initialize a videobuf2 queue 891 * @q: pointer to &struct vb2_queue with videobuf2 queue. 892 * This structure should be allocated in driver 893 * 894 * The &vb2_queue structure should be allocated by the driver. The driver is 895 * responsible of clearing it's content and setting initial values for some 896 * required entries before calling this function. 897 * 898 * .. note:: 899 * 900 * The following fields at @q should be set before calling this function: 901 * &vb2_queue->ops, &vb2_queue->mem_ops, &vb2_queue->type. 902 */ 903 int vb2_core_queue_init(struct vb2_queue *q); 904 905 /** 906 * vb2_core_queue_release() - stop streaming, release the queue and free memory 907 * @q: pointer to &struct vb2_queue with videobuf2 queue. 908 * 909 * This function stops streaming and performs necessary clean ups, including 910 * freeing video buffer memory. The driver is responsible for freeing 911 * the &struct vb2_queue itself. 912 */ 913 void vb2_core_queue_release(struct vb2_queue *q); 914 915 /** 916 * vb2_queue_error() - signal a fatal error on the queue 917 * @q: pointer to &struct vb2_queue with videobuf2 queue. 918 * 919 * Flag that a fatal unrecoverable error has occurred and wake up all processes 920 * waiting on the queue. Polling will now set %EPOLLERR and queuing and dequeuing 921 * buffers will return %-EIO. 922 * 923 * The error flag will be cleared when canceling the queue, either from 924 * vb2_streamoff() or vb2_queue_release(). Drivers should thus not call this 925 * function before starting the stream, otherwise the error flag will remain set 926 * until the queue is released when closing the device node. 927 */ 928 void vb2_queue_error(struct vb2_queue *q); 929 930 /** 931 * vb2_mmap() - map video buffers into application address space. 932 * @q: pointer to &struct vb2_queue with videobuf2 queue. 933 * @vma: pointer to &struct vm_area_struct with the vma passed 934 * to the mmap file operation handler in the driver. 935 * 936 * Should be called from mmap file operation handler of a driver. 937 * This function maps one plane of one of the available video buffers to 938 * userspace. To map whole video memory allocated on reqbufs, this function 939 * has to be called once per each plane per each buffer previously allocated. 940 * 941 * When the userspace application calls mmap, it passes to it an offset returned 942 * to it earlier by the means of &v4l2_ioctl_ops->vidioc_querybuf handler. 943 * That offset acts as a "cookie", which is then used to identify the plane 944 * to be mapped. 945 * 946 * This function finds a plane with a matching offset and a mapping is performed 947 * by the means of a provided memory operation. 948 * 949 * The return values from this function are intended to be directly returned 950 * from the mmap handler in driver. 951 */ 952 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma); 953 954 #ifndef CONFIG_MMU 955 /** 956 * vb2_get_unmapped_area - map video buffers into application address space. 957 * @q: pointer to &struct vb2_queue with videobuf2 queue. 958 * @addr: memory address. 959 * @len: buffer size. 960 * @pgoff: page offset. 961 * @flags: memory flags. 962 * 963 * This function is used in noMMU platforms to propose address mapping 964 * for a given buffer. It's intended to be used as a handler for the 965 * &file_operations->get_unmapped_area operation. 966 * 967 * This is called by the mmap() syscall routines will call this 968 * to get a proposed address for the mapping, when ``!CONFIG_MMU``. 969 */ 970 unsigned long vb2_get_unmapped_area(struct vb2_queue *q, 971 unsigned long addr, 972 unsigned long len, 973 unsigned long pgoff, 974 unsigned long flags); 975 #endif 976 977 /** 978 * vb2_core_poll() - implements poll syscall() logic. 979 * @q: pointer to &struct vb2_queue with videobuf2 queue. 980 * @file: &struct file argument passed to the poll 981 * file operation handler. 982 * @wait: &poll_table wait argument passed to the poll 983 * file operation handler. 984 * 985 * This function implements poll file operation handler for a driver. 986 * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will 987 * be informed that the file descriptor of a video device is available for 988 * reading. 989 * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor 990 * will be reported as available for writing. 991 * 992 * The return values from this function are intended to be directly returned 993 * from poll handler in driver. 994 */ 995 __poll_t vb2_core_poll(struct vb2_queue *q, struct file *file, 996 poll_table *wait); 997 998 /** 999 * vb2_read() - implements read() syscall logic. 1000 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1001 * @data: pointed to target userspace buffer 1002 * @count: number of bytes to read 1003 * @ppos: file handle position tracking pointer 1004 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) 1005 */ 1006 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, 1007 loff_t *ppos, int nonblock); 1008 /** 1009 * vb2_read() - implements write() syscall logic. 1010 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1011 * @data: pointed to target userspace buffer 1012 * @count: number of bytes to write 1013 * @ppos: file handle position tracking pointer 1014 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) 1015 */ 1016 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, 1017 loff_t *ppos, int nonblock); 1018 1019 /** 1020 * typedef vb2_thread_fnc - callback function for use with vb2_thread. 1021 * 1022 * @vb: pointer to struct &vb2_buffer. 1023 * @priv: pointer to a private data. 1024 * 1025 * This is called whenever a buffer is dequeued in the thread. 1026 */ 1027 typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv); 1028 1029 /** 1030 * vb2_thread_start() - start a thread for the given queue. 1031 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1032 * @fnc: &vb2_thread_fnc callback function. 1033 * @priv: priv pointer passed to the callback function. 1034 * @thread_name:the name of the thread. This will be prefixed with "vb2-". 1035 * 1036 * This starts a thread that will queue and dequeue until an error occurs 1037 * or vb2_thread_stop() is called. 1038 * 1039 * .. attention:: 1040 * 1041 * This function should not be used for anything else but the videobuf2-dvb 1042 * support. If you think you have another good use-case for this, then please 1043 * contact the linux-media mailing list first. 1044 */ 1045 int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, 1046 const char *thread_name); 1047 1048 /** 1049 * vb2_thread_stop() - stop the thread for the given queue. 1050 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1051 */ 1052 int vb2_thread_stop(struct vb2_queue *q); 1053 1054 /** 1055 * vb2_is_streaming() - return streaming status of the queue. 1056 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1057 */ 1058 static inline bool vb2_is_streaming(struct vb2_queue *q) 1059 { 1060 return q->streaming; 1061 } 1062 1063 /** 1064 * vb2_fileio_is_active() - return true if fileio is active. 1065 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1066 * 1067 * This returns true if read() or write() is used to stream the data 1068 * as opposed to stream I/O. This is almost never an important distinction, 1069 * except in rare cases. One such case is that using read() or write() to 1070 * stream a format using %V4L2_FIELD_ALTERNATE is not allowed since there 1071 * is no way you can pass the field information of each buffer to/from 1072 * userspace. A driver that supports this field format should check for 1073 * this in the &vb2_ops->queue_setup op and reject it if this function returns 1074 * true. 1075 */ 1076 static inline bool vb2_fileio_is_active(struct vb2_queue *q) 1077 { 1078 return q->fileio; 1079 } 1080 1081 /** 1082 * vb2_is_busy() - return busy status of the queue. 1083 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1084 * 1085 * This function checks if queue has any buffers allocated. 1086 */ 1087 static inline bool vb2_is_busy(struct vb2_queue *q) 1088 { 1089 return (q->num_buffers > 0); 1090 } 1091 1092 /** 1093 * vb2_get_drv_priv() - return driver private data associated with the queue. 1094 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1095 */ 1096 static inline void *vb2_get_drv_priv(struct vb2_queue *q) 1097 { 1098 return q->drv_priv; 1099 } 1100 1101 /** 1102 * vb2_set_plane_payload() - set bytesused for the plane @plane_no. 1103 * @vb: pointer to &struct vb2_buffer to which the plane in 1104 * question belongs to. 1105 * @plane_no: plane number for which payload should be set. 1106 * @size: payload in bytes. 1107 */ 1108 static inline void vb2_set_plane_payload(struct vb2_buffer *vb, 1109 unsigned int plane_no, unsigned long size) 1110 { 1111 if (plane_no < vb->num_planes) 1112 vb->planes[plane_no].bytesused = size; 1113 } 1114 1115 /** 1116 * vb2_get_plane_payload() - get bytesused for the plane plane_no 1117 * @vb: pointer to &struct vb2_buffer to which the plane in 1118 * question belongs to. 1119 * @plane_no: plane number for which payload should be set. 1120 */ 1121 static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, 1122 unsigned int plane_no) 1123 { 1124 if (plane_no < vb->num_planes) 1125 return vb->planes[plane_no].bytesused; 1126 return 0; 1127 } 1128 1129 /** 1130 * vb2_plane_size() - return plane size in bytes. 1131 * @vb: pointer to &struct vb2_buffer to which the plane in 1132 * question belongs to. 1133 * @plane_no: plane number for which size should be returned. 1134 */ 1135 static inline unsigned long 1136 vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no) 1137 { 1138 if (plane_no < vb->num_planes) 1139 return vb->planes[plane_no].length; 1140 return 0; 1141 } 1142 1143 /** 1144 * vb2_start_streaming_called() - return streaming status of driver. 1145 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1146 */ 1147 static inline bool vb2_start_streaming_called(struct vb2_queue *q) 1148 { 1149 return q->start_streaming_called; 1150 } 1151 1152 /** 1153 * vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue. 1154 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1155 */ 1156 static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) 1157 { 1158 q->last_buffer_dequeued = false; 1159 } 1160 1161 /* 1162 * The following functions are not part of the vb2 core API, but are useful 1163 * functions for videobuf2-*. 1164 */ 1165 1166 /** 1167 * vb2_buffer_in_use() - return true if the buffer is in use and 1168 * the queue cannot be freed (by the means of VIDIOC_REQBUFS(0)) call. 1169 * 1170 * @vb: buffer for which plane size should be returned. 1171 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1172 */ 1173 bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); 1174 1175 /** 1176 * vb2_verify_memory_type() - Check whether the memory type and buffer type 1177 * passed to a buffer operation are compatible with the queue. 1178 * 1179 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1180 * @memory: memory model, as defined by enum &vb2_memory. 1181 * @type: private buffer type whose content is defined by the vb2-core 1182 * caller. For example, for V4L2, it should match 1183 * the types defined on enum &v4l2_buf_type. 1184 */ 1185 int vb2_verify_memory_type(struct vb2_queue *q, 1186 enum vb2_memory memory, unsigned int type); 1187 1188 /** 1189 * vb2_request_object_is_buffer() - return true if the object is a buffer 1190 * 1191 * @obj: the request object. 1192 */ 1193 bool vb2_request_object_is_buffer(struct media_request_object *obj); 1194 1195 /** 1196 * vb2_request_buffer_cnt() - return the number of buffers in the request 1197 * 1198 * @req: the request. 1199 */ 1200 unsigned int vb2_request_buffer_cnt(struct media_request *req); 1201 1202 #endif /* _MEDIA_VIDEOBUF2_CORE_H */ 1203