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 * copied_timestamp: the timestamp of this capture buffer was copied 266 * from an output buffer. 267 * queued_entry: entry on the queued buffers list, which holds 268 * all buffers queued from userspace 269 * done_entry: entry on the list that stores all buffers ready 270 * to be dequeued to userspace 271 * vb2_plane: per-plane information; do not change 272 */ 273 enum vb2_buffer_state state; 274 unsigned int synced:1; 275 unsigned int prepared:1; 276 unsigned int copied_timestamp:1; 277 278 struct vb2_plane planes[VB2_MAX_PLANES]; 279 struct list_head queued_entry; 280 struct list_head done_entry; 281 #ifdef CONFIG_VIDEO_ADV_DEBUG 282 /* 283 * Counters for how often these buffer-related ops are 284 * called. Used to check for unbalanced ops. 285 */ 286 u32 cnt_mem_alloc; 287 u32 cnt_mem_put; 288 u32 cnt_mem_get_dmabuf; 289 u32 cnt_mem_get_userptr; 290 u32 cnt_mem_put_userptr; 291 u32 cnt_mem_prepare; 292 u32 cnt_mem_finish; 293 u32 cnt_mem_attach_dmabuf; 294 u32 cnt_mem_detach_dmabuf; 295 u32 cnt_mem_map_dmabuf; 296 u32 cnt_mem_unmap_dmabuf; 297 u32 cnt_mem_vaddr; 298 u32 cnt_mem_cookie; 299 u32 cnt_mem_num_users; 300 u32 cnt_mem_mmap; 301 302 u32 cnt_buf_out_validate; 303 u32 cnt_buf_init; 304 u32 cnt_buf_prepare; 305 u32 cnt_buf_finish; 306 u32 cnt_buf_cleanup; 307 u32 cnt_buf_queue; 308 u32 cnt_buf_request_complete; 309 310 /* This counts the number of calls to vb2_buffer_done() */ 311 u32 cnt_buf_done; 312 #endif 313 }; 314 315 /** 316 * struct vb2_ops - driver-specific callbacks. 317 * 318 * These operations are not called from interrupt context except where 319 * mentioned specifically. 320 * 321 * @queue_setup: called from VIDIOC_REQBUFS() and VIDIOC_CREATE_BUFS() 322 * handlers before memory allocation. It can be called 323 * twice: if the original number of requested buffers 324 * could not be allocated, then it will be called a 325 * second time with the actually allocated number of 326 * buffers to verify if that is OK. 327 * The driver should return the required number of buffers 328 * in \*num_buffers, the required number of planes per 329 * buffer in \*num_planes, the size of each plane should be 330 * set in the sizes\[\] array and optional per-plane 331 * allocator specific device in the alloc_devs\[\] array. 332 * When called from VIDIOC_REQBUFS(), \*num_planes == 0, 333 * the driver has to use the currently configured format to 334 * determine the plane sizes and \*num_buffers is the total 335 * number of buffers that are being allocated. When called 336 * from VIDIOC_CREATE_BUFS(), \*num_planes != 0 and it 337 * describes the requested number of planes and sizes\[\] 338 * contains the requested plane sizes. In this case 339 * \*num_buffers are being allocated additionally to 340 * q->num_buffers. If either \*num_planes or the requested 341 * sizes are invalid callback must return %-EINVAL. 342 * @wait_prepare: release any locks taken while calling vb2 functions; 343 * it is called before an ioctl needs to wait for a new 344 * buffer to arrive; required to avoid a deadlock in 345 * blocking access type. 346 * @wait_finish: reacquire all locks released in the previous callback; 347 * required to continue operation after sleeping while 348 * waiting for a new buffer to arrive. 349 * @buf_out_validate: called when the output buffer is prepared or queued 350 * to a request; drivers can use this to validate 351 * userspace-provided information; this is required only 352 * for OUTPUT queues. 353 * @buf_init: called once after allocating a buffer (in MMAP case) 354 * or after acquiring a new USERPTR buffer; drivers may 355 * perform additional buffer-related initialization; 356 * initialization failure (return != 0) will prevent 357 * queue setup from completing successfully; optional. 358 * @buf_prepare: called every time the buffer is queued from userspace 359 * and from the VIDIOC_PREPARE_BUF() ioctl; drivers may 360 * perform any initialization required before each 361 * hardware operation in this callback; drivers can 362 * access/modify the buffer here as it is still synced for 363 * the CPU; drivers that support VIDIOC_CREATE_BUFS() must 364 * also validate the buffer size; if an error is returned, 365 * the buffer will not be queued in driver; optional. 366 * @buf_finish: called before every dequeue of the buffer back to 367 * userspace; the buffer is synced for the CPU, so drivers 368 * can access/modify the buffer contents; drivers may 369 * perform any operations required before userspace 370 * accesses the buffer; optional. The buffer state can be 371 * one of the following: %DONE and %ERROR occur while 372 * streaming is in progress, and the %PREPARED state occurs 373 * when the queue has been canceled and all pending 374 * buffers are being returned to their default %DEQUEUED 375 * state. Typically you only have to do something if the 376 * state is %VB2_BUF_STATE_DONE, since in all other cases 377 * the buffer contents will be ignored anyway. 378 * @buf_cleanup: called once before the buffer is freed; drivers may 379 * perform any additional cleanup; optional. 380 * @start_streaming: called once to enter 'streaming' state; the driver may 381 * receive buffers with @buf_queue callback 382 * before @start_streaming is called; the driver gets the 383 * number of already queued buffers in count parameter; 384 * driver can return an error if hardware fails, in that 385 * case all buffers that have been already given by 386 * the @buf_queue callback are to be returned by the driver 387 * by calling vb2_buffer_done() with %VB2_BUF_STATE_QUEUED 388 * or %VB2_BUF_STATE_REQUEUEING. If you need a minimum 389 * number of buffers before you can start streaming, then 390 * set &vb2_queue->min_buffers_needed. If that is non-zero 391 * then @start_streaming won't be called until at least 392 * that many buffers have been queued up by userspace. 393 * @stop_streaming: called when 'streaming' state must be disabled; driver 394 * should stop any DMA transactions or wait until they 395 * finish and give back all buffers it got from &buf_queue 396 * callback by calling vb2_buffer_done() with either 397 * %VB2_BUF_STATE_DONE or %VB2_BUF_STATE_ERROR; may use 398 * vb2_wait_for_all_buffers() function 399 * @buf_queue: passes buffer vb to the driver; driver may start 400 * hardware operation on this buffer; driver should give 401 * the buffer back by calling vb2_buffer_done() function; 402 * it is always called after calling VIDIOC_STREAMON() 403 * ioctl; might be called before @start_streaming callback 404 * if user pre-queued buffers before calling 405 * VIDIOC_STREAMON(). 406 * @buf_request_complete: a buffer that was never queued to the driver but is 407 * associated with a queued request was canceled. 408 * The driver will have to mark associated objects in the 409 * request as completed; required if requests are 410 * supported. 411 */ 412 struct vb2_ops { 413 int (*queue_setup)(struct vb2_queue *q, 414 unsigned int *num_buffers, unsigned int *num_planes, 415 unsigned int sizes[], struct device *alloc_devs[]); 416 417 void (*wait_prepare)(struct vb2_queue *q); 418 void (*wait_finish)(struct vb2_queue *q); 419 420 int (*buf_out_validate)(struct vb2_buffer *vb); 421 int (*buf_init)(struct vb2_buffer *vb); 422 int (*buf_prepare)(struct vb2_buffer *vb); 423 void (*buf_finish)(struct vb2_buffer *vb); 424 void (*buf_cleanup)(struct vb2_buffer *vb); 425 426 int (*start_streaming)(struct vb2_queue *q, unsigned int count); 427 void (*stop_streaming)(struct vb2_queue *q); 428 429 void (*buf_queue)(struct vb2_buffer *vb); 430 431 void (*buf_request_complete)(struct vb2_buffer *vb); 432 }; 433 434 /** 435 * struct vb2_buf_ops - driver-specific callbacks. 436 * 437 * @verify_planes_array: Verify that a given user space structure contains 438 * enough planes for the buffer. This is called 439 * for each dequeued buffer. 440 * @init_buffer: given a &vb2_buffer initialize the extra data after 441 * struct vb2_buffer. 442 * For V4L2 this is a &struct vb2_v4l2_buffer. 443 * @fill_user_buffer: given a &vb2_buffer fill in the userspace structure. 444 * For V4L2 this is a &struct v4l2_buffer. 445 * @fill_vb2_buffer: given a userspace structure, fill in the &vb2_buffer. 446 * If the userspace structure is invalid, then this op 447 * will return an error. 448 * @copy_timestamp: copy the timestamp from a userspace structure to 449 * the &struct vb2_buffer. 450 */ 451 struct vb2_buf_ops { 452 int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb); 453 void (*init_buffer)(struct vb2_buffer *vb); 454 void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb); 455 int (*fill_vb2_buffer)(struct vb2_buffer *vb, struct vb2_plane *planes); 456 void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb); 457 }; 458 459 /** 460 * struct vb2_queue - a videobuf queue. 461 * 462 * @type: private buffer type whose content is defined by the vb2-core 463 * caller. For example, for V4L2, it should match 464 * the types defined on &enum v4l2_buf_type. 465 * @io_modes: supported io methods (see &enum vb2_io_modes). 466 * @alloc_devs: &struct device memory type/allocator-specific per-plane device 467 * @dev: device to use for the default allocation context if the driver 468 * doesn't fill in the @alloc_devs array. 469 * @dma_attrs: DMA attributes to use for the DMA. 470 * @bidirectional: when this flag is set the DMA direction for the buffers of 471 * this queue will be overridden with %DMA_BIDIRECTIONAL direction. 472 * This is useful in cases where the hardware (firmware) writes to 473 * a buffer which is mapped as read (%DMA_TO_DEVICE), or reads from 474 * buffer which is mapped for write (%DMA_FROM_DEVICE) in order 475 * to satisfy some internal hardware restrictions or adds a padding 476 * needed by the processing algorithm. In case the DMA mapping is 477 * not bidirectional but the hardware (firmware) trying to access 478 * the buffer (in the opposite direction) this could lead to an 479 * IOMMU protection faults. 480 * @fileio_read_once: report EOF after reading the first buffer 481 * @fileio_write_immediately: queue buffer after each write() call 482 * @allow_zero_bytesused: allow bytesused == 0 to be passed to the driver 483 * @quirk_poll_must_check_waiting_for_buffers: Return %EPOLLERR at poll when QBUF 484 * has not been called. This is a vb1 idiom that has been adopted 485 * also by vb2. 486 * @supports_requests: this queue supports the Request API. 487 * @uses_qbuf: qbuf was used directly for this queue. Set to 1 the first 488 * time this is called. Set to 0 when the queue is canceled. 489 * If this is 1, then you cannot queue buffers from a request. 490 * @uses_requests: requests are used for this queue. Set to 1 the first time 491 * a request is queued. Set to 0 when the queue is canceled. 492 * If this is 1, then you cannot queue buffers directly. 493 * @lock: pointer to a mutex that protects the &struct vb2_queue. The 494 * driver can set this to a mutex to let the v4l2 core serialize 495 * the queuing ioctls. If the driver wants to handle locking 496 * itself, then this should be set to NULL. This lock is not used 497 * by the videobuf2 core API. 498 * @owner: The filehandle that 'owns' the buffers, i.e. the filehandle 499 * that called reqbufs, create_buffers or started fileio. 500 * This field is not used by the videobuf2 core API, but it allows 501 * drivers to easily associate an owner filehandle with the queue. 502 * @ops: driver-specific callbacks 503 * @mem_ops: memory allocator specific callbacks 504 * @buf_ops: callbacks to deliver buffer information. 505 * between user-space and kernel-space. 506 * @drv_priv: driver private data. 507 * @buf_struct_size: size of the driver-specific buffer structure; 508 * "0" indicates the driver doesn't want to use a custom buffer 509 * structure type. for example, ``sizeof(struct vb2_v4l2_buffer)`` 510 * will be used for v4l2. 511 * @timestamp_flags: Timestamp flags; ``V4L2_BUF_FLAG_TIMESTAMP_*`` and 512 * ``V4L2_BUF_FLAG_TSTAMP_SRC_*`` 513 * @gfp_flags: additional gfp flags used when allocating the buffers. 514 * Typically this is 0, but it may be e.g. %GFP_DMA or %__GFP_DMA32 515 * to force the buffer allocation to a specific memory zone. 516 * @min_buffers_needed: the minimum number of buffers needed before 517 * @start_streaming can be called. Used when a DMA engine 518 * cannot be started unless at least this number of buffers 519 * have been queued into the driver. 520 */ 521 /* 522 * Private elements (won't appear at the uAPI book): 523 * @mmap_lock: private mutex used when buffers are allocated/freed/mmapped 524 * @memory: current memory type used 525 * @dma_dir: DMA mapping direction. 526 * @bufs: videobuf buffer structures 527 * @num_buffers: number of allocated/used buffers 528 * @queued_list: list of buffers currently queued from userspace 529 * @queued_count: number of buffers queued and ready for streaming. 530 * @owned_by_drv_count: number of buffers owned by the driver 531 * @done_list: list of buffers ready to be dequeued to userspace 532 * @done_lock: lock to protect done_list list 533 * @done_wq: waitqueue for processes waiting for buffers ready to be dequeued 534 * @streaming: current streaming state 535 * @start_streaming_called: @start_streaming was called successfully and we 536 * started streaming. 537 * @error: a fatal error occurred on the queue 538 * @waiting_for_buffers: used in poll() to check if vb2 is still waiting for 539 * buffers. Only set for capture queues if qbuf has not yet been 540 * called since poll() needs to return %EPOLLERR in that situation. 541 * @is_multiplanar: set if buffer type is multiplanar 542 * @is_output: set if buffer type is output 543 * @copy_timestamp: set if vb2-core should set timestamps 544 * @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the 545 * last decoded buffer was already dequeued. Set for capture queues 546 * when a buffer with the %V4L2_BUF_FLAG_LAST is dequeued. 547 * @fileio: file io emulator internal data, used only if emulator is active 548 * @threadio: thread io internal data, used only if thread is active 549 */ 550 struct vb2_queue { 551 unsigned int type; 552 unsigned int io_modes; 553 struct device *dev; 554 unsigned long dma_attrs; 555 unsigned bidirectional:1; 556 unsigned fileio_read_once:1; 557 unsigned fileio_write_immediately:1; 558 unsigned allow_zero_bytesused:1; 559 unsigned quirk_poll_must_check_waiting_for_buffers:1; 560 unsigned supports_requests:1; 561 unsigned uses_qbuf:1; 562 unsigned uses_requests:1; 563 564 struct mutex *lock; 565 void *owner; 566 567 const struct vb2_ops *ops; 568 const struct vb2_mem_ops *mem_ops; 569 const struct vb2_buf_ops *buf_ops; 570 571 void *drv_priv; 572 unsigned int buf_struct_size; 573 u32 timestamp_flags; 574 gfp_t gfp_flags; 575 u32 min_buffers_needed; 576 577 struct device *alloc_devs[VB2_MAX_PLANES]; 578 579 /* private: internal use only */ 580 struct mutex mmap_lock; 581 unsigned int memory; 582 enum dma_data_direction dma_dir; 583 struct vb2_buffer *bufs[VB2_MAX_FRAME]; 584 unsigned int num_buffers; 585 586 struct list_head queued_list; 587 unsigned int queued_count; 588 589 atomic_t owned_by_drv_count; 590 struct list_head done_list; 591 spinlock_t done_lock; 592 wait_queue_head_t done_wq; 593 594 unsigned int streaming:1; 595 unsigned int start_streaming_called:1; 596 unsigned int error:1; 597 unsigned int waiting_for_buffers:1; 598 unsigned int is_multiplanar:1; 599 unsigned int is_output:1; 600 unsigned int copy_timestamp:1; 601 unsigned int last_buffer_dequeued:1; 602 603 struct vb2_fileio_data *fileio; 604 struct vb2_threadio_data *threadio; 605 606 #ifdef CONFIG_VIDEO_ADV_DEBUG 607 /* 608 * Counters for how often these queue-related ops are 609 * called. Used to check for unbalanced ops. 610 */ 611 u32 cnt_queue_setup; 612 u32 cnt_wait_prepare; 613 u32 cnt_wait_finish; 614 u32 cnt_start_streaming; 615 u32 cnt_stop_streaming; 616 #endif 617 }; 618 619 /** 620 * vb2_plane_vaddr() - Return a kernel virtual address of a given plane. 621 * @vb: pointer to &struct vb2_buffer to which the plane in 622 * question belongs to. 623 * @plane_no: plane number for which the address is to be returned. 624 * 625 * This function returns a kernel virtual address of a given plane if 626 * such a mapping exist, NULL otherwise. 627 */ 628 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); 629 630 /** 631 * vb2_plane_cookie() - Return allocator specific cookie for the given plane. 632 * @vb: pointer to &struct vb2_buffer to which the plane in 633 * question belongs to. 634 * @plane_no: plane number for which the cookie is to be returned. 635 * 636 * This function returns an allocator specific cookie for a given plane if 637 * available, NULL otherwise. The allocator should provide some simple static 638 * inline function, which would convert this cookie to the allocator specific 639 * type that can be used directly by the driver to access the buffer. This can 640 * be for example physical address, pointer to scatter list or IOMMU mapping. 641 */ 642 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); 643 644 /** 645 * vb2_buffer_done() - inform videobuf that an operation on a buffer 646 * is finished. 647 * @vb: pointer to &struct vb2_buffer to be used. 648 * @state: state of the buffer, as defined by &enum vb2_buffer_state. 649 * Either %VB2_BUF_STATE_DONE if the operation finished 650 * successfully, %VB2_BUF_STATE_ERROR if the operation finished 651 * with an error or any of %VB2_BUF_STATE_QUEUED or 652 * %VB2_BUF_STATE_REQUEUEING if the driver wants to 653 * requeue buffers (see below). 654 * 655 * This function should be called by the driver after a hardware operation on 656 * a buffer is finished and the buffer may be returned to userspace. The driver 657 * cannot use this buffer anymore until it is queued back to it by videobuf 658 * by the means of &vb2_ops->buf_queue callback. Only buffers previously queued 659 * to the driver by &vb2_ops->buf_queue can be passed to this function. 660 * 661 * While streaming a buffer can only be returned in state DONE or ERROR. 662 * The &vb2_ops->start_streaming op can also return them in case the DMA engine 663 * cannot be started for some reason. In that case the buffers should be 664 * returned with state QUEUED or REQUEUEING to put them back into the queue. 665 * 666 * %VB2_BUF_STATE_REQUEUEING is like %VB2_BUF_STATE_QUEUED, but it also calls 667 * &vb2_ops->buf_queue to queue buffers back to the driver. Note that calling 668 * vb2_buffer_done(..., VB2_BUF_STATE_REQUEUEING) from interrupt context will 669 * result in &vb2_ops->buf_queue being called in interrupt context as well. 670 */ 671 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state); 672 673 /** 674 * vb2_discard_done() - discard all buffers marked as DONE. 675 * @q: pointer to &struct vb2_queue with videobuf2 queue. 676 * 677 * This function is intended to be used with suspend/resume operations. It 678 * discards all 'done' buffers as they would be too old to be requested after 679 * resume. 680 * 681 * Drivers must stop the hardware and synchronize with interrupt handlers and/or 682 * delayed works before calling this function to make sure no buffer will be 683 * touched by the driver and/or hardware. 684 */ 685 void vb2_discard_done(struct vb2_queue *q); 686 687 /** 688 * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2. 689 * @q: pointer to &struct vb2_queue with videobuf2 queue. 690 * 691 * This function will wait until all buffers that have been given to the driver 692 * by &vb2_ops->buf_queue are given back to vb2 with vb2_buffer_done(). It 693 * doesn't call &vb2_ops->wait_prepare/&vb2_ops->wait_finish pair. 694 * It is intended to be called with all locks taken, for example from 695 * &vb2_ops->stop_streaming callback. 696 */ 697 int vb2_wait_for_all_buffers(struct vb2_queue *q); 698 699 /** 700 * vb2_core_querybuf() - query video buffer information. 701 * @q: pointer to &struct vb2_queue with videobuf2 queue. 702 * @index: id number of the buffer. 703 * @pb: buffer struct passed from userspace. 704 * 705 * Videobuf2 core helper to implement VIDIOC_QUERYBUF() operation. It is called 706 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 707 * 708 * The passed buffer should have been verified. 709 * 710 * This function fills the relevant information for the userspace. 711 * 712 * Return: returns zero on success; an error code otherwise. 713 */ 714 void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb); 715 716 /** 717 * vb2_core_reqbufs() - Initiate streaming. 718 * @q: pointer to &struct vb2_queue with videobuf2 queue. 719 * @memory: memory type, as defined by &enum vb2_memory. 720 * @count: requested buffer count. 721 * 722 * Videobuf2 core helper to implement VIDIOC_REQBUF() operation. It is called 723 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 724 * 725 * This function: 726 * 727 * #) verifies streaming parameters passed from the userspace; 728 * #) sets up the queue; 729 * #) negotiates number of buffers and planes per buffer with the driver 730 * to be used during streaming; 731 * #) allocates internal buffer structures (&struct vb2_buffer), according to 732 * the agreed parameters; 733 * #) for MMAP memory type, allocates actual video memory, using the 734 * memory handling/allocation routines provided during queue initialization. 735 * 736 * If req->count is 0, all the memory will be freed instead. 737 * 738 * If the queue has been allocated previously by a previous vb2_core_reqbufs() 739 * call and the queue is not busy, memory will be reallocated. 740 * 741 * Return: returns zero on success; an error code otherwise. 742 */ 743 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 744 unsigned int *count); 745 746 /** 747 * vb2_core_create_bufs() - Allocate buffers and any required auxiliary structs 748 * @q: pointer to &struct vb2_queue with videobuf2 queue. 749 * @memory: memory type, as defined by &enum vb2_memory. 750 * @count: requested buffer count. 751 * @requested_planes: number of planes requested. 752 * @requested_sizes: array with the size of the planes. 753 * 754 * Videobuf2 core helper to implement VIDIOC_CREATE_BUFS() operation. It is 755 * called internally by VB2 by an API-specific handler, like 756 * ``videobuf2-v4l2.h``. 757 * 758 * This function: 759 * 760 * #) verifies parameter sanity; 761 * #) calls the &vb2_ops->queue_setup queue operation; 762 * #) performs any necessary memory allocations. 763 * 764 * Return: returns zero on success; an error code otherwise. 765 */ 766 int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, 767 unsigned int *count, unsigned int requested_planes, 768 const unsigned int requested_sizes[]); 769 770 /** 771 * vb2_core_prepare_buf() - Pass ownership of a buffer from userspace 772 * to the kernel. 773 * @q: pointer to &struct vb2_queue with videobuf2 queue. 774 * @index: id number of the buffer. 775 * @pb: buffer structure passed from userspace to 776 * &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver. 777 * 778 * Videobuf2 core helper to implement VIDIOC_PREPARE_BUF() operation. It is 779 * called internally by VB2 by an API-specific handler, like 780 * ``videobuf2-v4l2.h``. 781 * 782 * The passed buffer should have been verified. 783 * 784 * This function calls vb2_ops->buf_prepare callback in the driver 785 * (if provided), in which driver-specific buffer initialization can 786 * be performed. 787 * 788 * Return: returns zero on success; an error code otherwise. 789 */ 790 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb); 791 792 /** 793 * vb2_core_qbuf() - Queue a buffer from userspace 794 * 795 * @q: pointer to &struct vb2_queue with videobuf2 queue. 796 * @index: id number of the buffer 797 * @pb: buffer structure passed from userspace to 798 * v4l2_ioctl_ops->vidioc_qbuf handler in driver 799 * @req: pointer to &struct media_request, may be NULL. 800 * 801 * Videobuf2 core helper to implement VIDIOC_QBUF() operation. It is called 802 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 803 * 804 * This function: 805 * 806 * #) If @req is non-NULL, then the buffer will be bound to this 807 * media request and it returns. The buffer will be prepared and 808 * queued to the driver (i.e. the next two steps) when the request 809 * itself is queued. 810 * #) if necessary, calls &vb2_ops->buf_prepare callback in the driver 811 * (if provided), in which driver-specific buffer initialization can 812 * be performed; 813 * #) if streaming is on, queues the buffer in driver by the means of 814 * &vb2_ops->buf_queue callback for processing. 815 * 816 * Return: returns zero on success; an error code otherwise. 817 */ 818 int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, 819 struct media_request *req); 820 821 /** 822 * vb2_core_dqbuf() - Dequeue a buffer to the userspace 823 * @q: pointer to &struct vb2_queue with videobuf2 queue 824 * @pindex: pointer to the buffer index. May be NULL 825 * @pb: buffer structure passed from userspace to 826 * v4l2_ioctl_ops->vidioc_dqbuf handler in driver. 827 * @nonblocking: if true, this call will not sleep waiting for a buffer if no 828 * buffers ready for dequeuing are present. Normally the driver 829 * would be passing (file->f_flags & O_NONBLOCK) here. 830 * 831 * Videobuf2 core helper to implement VIDIOC_DQBUF() operation. It is called 832 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 833 * 834 * This function: 835 * 836 * #) calls buf_finish callback in the driver (if provided), in which 837 * driver can perform any additional operations that may be required before 838 * returning the buffer to userspace, such as cache sync, 839 * #) the buffer struct members are filled with relevant information for 840 * the userspace. 841 * 842 * Return: returns zero on success; an error code otherwise. 843 */ 844 int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb, 845 bool nonblocking); 846 847 /** 848 * vb2_core_streamon() - Implements VB2 stream ON logic 849 * 850 * @q: pointer to &struct vb2_queue with videobuf2 queue 851 * @type: type of the queue to be started. 852 * For V4L2, this is defined by &enum v4l2_buf_type type. 853 * 854 * Videobuf2 core helper to implement VIDIOC_STREAMON() operation. It is called 855 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 856 * 857 * Return: returns zero on success; an error code otherwise. 858 */ 859 int vb2_core_streamon(struct vb2_queue *q, unsigned int type); 860 861 /** 862 * vb2_core_streamoff() - Implements VB2 stream OFF logic 863 * 864 * @q: pointer to &struct vb2_queue with videobuf2 queue 865 * @type: type of the queue to be started. 866 * For V4L2, this is defined by &enum v4l2_buf_type type. 867 * 868 * Videobuf2 core helper to implement VIDIOC_STREAMOFF() operation. It is 869 * called internally by VB2 by an API-specific handler, like 870 * ``videobuf2-v4l2.h``. 871 * 872 * Return: returns zero on success; an error code otherwise. 873 */ 874 int vb2_core_streamoff(struct vb2_queue *q, unsigned int type); 875 876 /** 877 * vb2_core_expbuf() - Export a buffer as a file descriptor. 878 * @q: pointer to &struct vb2_queue with videobuf2 queue. 879 * @fd: pointer to the file descriptor associated with DMABUF 880 * (set by driver). 881 * @type: buffer type. 882 * @index: id number of the buffer. 883 * @plane: index of the plane to be exported, 0 for single plane queues 884 * @flags: file flags for newly created file, as defined at 885 * include/uapi/asm-generic/fcntl.h. 886 * Currently, the only used flag is %O_CLOEXEC. 887 * is supported, refer to manual of open syscall for more details. 888 * 889 * 890 * Videobuf2 core helper to implement VIDIOC_EXPBUF() operation. It is called 891 * internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. 892 * 893 * Return: returns zero on success; an error code otherwise. 894 */ 895 int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, 896 unsigned int index, unsigned int plane, unsigned int flags); 897 898 /** 899 * vb2_core_queue_init() - initialize a videobuf2 queue 900 * @q: pointer to &struct vb2_queue with videobuf2 queue. 901 * This structure should be allocated in driver 902 * 903 * The &vb2_queue structure should be allocated by the driver. The driver is 904 * responsible of clearing it's content and setting initial values for some 905 * required entries before calling this function. 906 * 907 * .. note:: 908 * 909 * The following fields at @q should be set before calling this function: 910 * &vb2_queue->ops, &vb2_queue->mem_ops, &vb2_queue->type. 911 */ 912 int vb2_core_queue_init(struct vb2_queue *q); 913 914 /** 915 * vb2_core_queue_release() - stop streaming, release the queue and free memory 916 * @q: pointer to &struct vb2_queue with videobuf2 queue. 917 * 918 * This function stops streaming and performs necessary clean ups, including 919 * freeing video buffer memory. The driver is responsible for freeing 920 * the &struct vb2_queue itself. 921 */ 922 void vb2_core_queue_release(struct vb2_queue *q); 923 924 /** 925 * vb2_queue_error() - signal a fatal error on the queue 926 * @q: pointer to &struct vb2_queue with videobuf2 queue. 927 * 928 * Flag that a fatal unrecoverable error has occurred and wake up all processes 929 * waiting on the queue. Polling will now set %EPOLLERR and queuing and dequeuing 930 * buffers will return %-EIO. 931 * 932 * The error flag will be cleared when canceling the queue, either from 933 * vb2_streamoff() or vb2_queue_release(). Drivers should thus not call this 934 * function before starting the stream, otherwise the error flag will remain set 935 * until the queue is released when closing the device node. 936 */ 937 void vb2_queue_error(struct vb2_queue *q); 938 939 /** 940 * vb2_mmap() - map video buffers into application address space. 941 * @q: pointer to &struct vb2_queue with videobuf2 queue. 942 * @vma: pointer to &struct vm_area_struct with the vma passed 943 * to the mmap file operation handler in the driver. 944 * 945 * Should be called from mmap file operation handler of a driver. 946 * This function maps one plane of one of the available video buffers to 947 * userspace. To map whole video memory allocated on reqbufs, this function 948 * has to be called once per each plane per each buffer previously allocated. 949 * 950 * When the userspace application calls mmap, it passes to it an offset returned 951 * to it earlier by the means of &v4l2_ioctl_ops->vidioc_querybuf handler. 952 * That offset acts as a "cookie", which is then used to identify the plane 953 * to be mapped. 954 * 955 * This function finds a plane with a matching offset and a mapping is performed 956 * by the means of a provided memory operation. 957 * 958 * The return values from this function are intended to be directly returned 959 * from the mmap handler in driver. 960 */ 961 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma); 962 963 #ifndef CONFIG_MMU 964 /** 965 * vb2_get_unmapped_area - map video buffers into application address space. 966 * @q: pointer to &struct vb2_queue with videobuf2 queue. 967 * @addr: memory address. 968 * @len: buffer size. 969 * @pgoff: page offset. 970 * @flags: memory flags. 971 * 972 * This function is used in noMMU platforms to propose address mapping 973 * for a given buffer. It's intended to be used as a handler for the 974 * &file_operations->get_unmapped_area operation. 975 * 976 * This is called by the mmap() syscall routines will call this 977 * to get a proposed address for the mapping, when ``!CONFIG_MMU``. 978 */ 979 unsigned long vb2_get_unmapped_area(struct vb2_queue *q, 980 unsigned long addr, 981 unsigned long len, 982 unsigned long pgoff, 983 unsigned long flags); 984 #endif 985 986 /** 987 * vb2_core_poll() - implements poll syscall() logic. 988 * @q: pointer to &struct vb2_queue with videobuf2 queue. 989 * @file: &struct file argument passed to the poll 990 * file operation handler. 991 * @wait: &poll_table wait argument passed to the poll 992 * file operation handler. 993 * 994 * This function implements poll file operation handler for a driver. 995 * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will 996 * be informed that the file descriptor of a video device is available for 997 * reading. 998 * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor 999 * will be reported as available for writing. 1000 * 1001 * The return values from this function are intended to be directly returned 1002 * from poll handler in driver. 1003 */ 1004 __poll_t vb2_core_poll(struct vb2_queue *q, struct file *file, 1005 poll_table *wait); 1006 1007 /** 1008 * vb2_read() - implements read() syscall logic. 1009 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1010 * @data: pointed to target userspace buffer 1011 * @count: number of bytes to read 1012 * @ppos: file handle position tracking pointer 1013 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) 1014 */ 1015 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, 1016 loff_t *ppos, int nonblock); 1017 /** 1018 * vb2_read() - implements write() syscall logic. 1019 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1020 * @data: pointed to target userspace buffer 1021 * @count: number of bytes to write 1022 * @ppos: file handle position tracking pointer 1023 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) 1024 */ 1025 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, 1026 loff_t *ppos, int nonblock); 1027 1028 /** 1029 * typedef vb2_thread_fnc - callback function for use with vb2_thread. 1030 * 1031 * @vb: pointer to struct &vb2_buffer. 1032 * @priv: pointer to a private data. 1033 * 1034 * This is called whenever a buffer is dequeued in the thread. 1035 */ 1036 typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv); 1037 1038 /** 1039 * vb2_thread_start() - start a thread for the given queue. 1040 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1041 * @fnc: &vb2_thread_fnc callback function. 1042 * @priv: priv pointer passed to the callback function. 1043 * @thread_name:the name of the thread. This will be prefixed with "vb2-". 1044 * 1045 * This starts a thread that will queue and dequeue until an error occurs 1046 * or vb2_thread_stop() is called. 1047 * 1048 * .. attention:: 1049 * 1050 * This function should not be used for anything else but the videobuf2-dvb 1051 * support. If you think you have another good use-case for this, then please 1052 * contact the linux-media mailing list first. 1053 */ 1054 int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, 1055 const char *thread_name); 1056 1057 /** 1058 * vb2_thread_stop() - stop the thread for the given queue. 1059 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1060 */ 1061 int vb2_thread_stop(struct vb2_queue *q); 1062 1063 /** 1064 * vb2_is_streaming() - return streaming status of the queue. 1065 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1066 */ 1067 static inline bool vb2_is_streaming(struct vb2_queue *q) 1068 { 1069 return q->streaming; 1070 } 1071 1072 /** 1073 * vb2_fileio_is_active() - return true if fileio is active. 1074 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1075 * 1076 * This returns true if read() or write() is used to stream the data 1077 * as opposed to stream I/O. This is almost never an important distinction, 1078 * except in rare cases. One such case is that using read() or write() to 1079 * stream a format using %V4L2_FIELD_ALTERNATE is not allowed since there 1080 * is no way you can pass the field information of each buffer to/from 1081 * userspace. A driver that supports this field format should check for 1082 * this in the &vb2_ops->queue_setup op and reject it if this function returns 1083 * true. 1084 */ 1085 static inline bool vb2_fileio_is_active(struct vb2_queue *q) 1086 { 1087 return q->fileio; 1088 } 1089 1090 /** 1091 * vb2_is_busy() - return busy status of the queue. 1092 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1093 * 1094 * This function checks if queue has any buffers allocated. 1095 */ 1096 static inline bool vb2_is_busy(struct vb2_queue *q) 1097 { 1098 return (q->num_buffers > 0); 1099 } 1100 1101 /** 1102 * vb2_get_drv_priv() - return driver private data associated with the queue. 1103 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1104 */ 1105 static inline void *vb2_get_drv_priv(struct vb2_queue *q) 1106 { 1107 return q->drv_priv; 1108 } 1109 1110 /** 1111 * vb2_set_plane_payload() - set bytesused for the plane @plane_no. 1112 * @vb: pointer to &struct vb2_buffer to which the plane in 1113 * question belongs to. 1114 * @plane_no: plane number for which payload should be set. 1115 * @size: payload in bytes. 1116 */ 1117 static inline void vb2_set_plane_payload(struct vb2_buffer *vb, 1118 unsigned int plane_no, unsigned long size) 1119 { 1120 if (plane_no < vb->num_planes) 1121 vb->planes[plane_no].bytesused = size; 1122 } 1123 1124 /** 1125 * vb2_get_plane_payload() - get bytesused for the plane plane_no 1126 * @vb: pointer to &struct vb2_buffer to which the plane in 1127 * question belongs to. 1128 * @plane_no: plane number for which payload should be set. 1129 */ 1130 static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, 1131 unsigned int plane_no) 1132 { 1133 if (plane_no < vb->num_planes) 1134 return vb->planes[plane_no].bytesused; 1135 return 0; 1136 } 1137 1138 /** 1139 * vb2_plane_size() - return plane size in bytes. 1140 * @vb: pointer to &struct vb2_buffer to which the plane in 1141 * question belongs to. 1142 * @plane_no: plane number for which size should be returned. 1143 */ 1144 static inline unsigned long 1145 vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no) 1146 { 1147 if (plane_no < vb->num_planes) 1148 return vb->planes[plane_no].length; 1149 return 0; 1150 } 1151 1152 /** 1153 * vb2_start_streaming_called() - return streaming status of driver. 1154 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1155 */ 1156 static inline bool vb2_start_streaming_called(struct vb2_queue *q) 1157 { 1158 return q->start_streaming_called; 1159 } 1160 1161 /** 1162 * vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue. 1163 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1164 */ 1165 static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) 1166 { 1167 q->last_buffer_dequeued = false; 1168 } 1169 1170 /* 1171 * The following functions are not part of the vb2 core API, but are useful 1172 * functions for videobuf2-*. 1173 */ 1174 1175 /** 1176 * vb2_buffer_in_use() - return true if the buffer is in use and 1177 * the queue cannot be freed (by the means of VIDIOC_REQBUFS(0)) call. 1178 * 1179 * @vb: buffer for which plane size should be returned. 1180 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1181 */ 1182 bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); 1183 1184 /** 1185 * vb2_verify_memory_type() - Check whether the memory type and buffer type 1186 * passed to a buffer operation are compatible with the queue. 1187 * 1188 * @q: pointer to &struct vb2_queue with videobuf2 queue. 1189 * @memory: memory model, as defined by enum &vb2_memory. 1190 * @type: private buffer type whose content is defined by the vb2-core 1191 * caller. For example, for V4L2, it should match 1192 * the types defined on enum &v4l2_buf_type. 1193 */ 1194 int vb2_verify_memory_type(struct vb2_queue *q, 1195 enum vb2_memory memory, unsigned int type); 1196 1197 /** 1198 * vb2_request_object_is_buffer() - return true if the object is a buffer 1199 * 1200 * @obj: the request object. 1201 */ 1202 bool vb2_request_object_is_buffer(struct media_request_object *obj); 1203 1204 /** 1205 * vb2_request_buffer_cnt() - return the number of buffers in the request 1206 * 1207 * @req: the request. 1208 */ 1209 unsigned int vb2_request_buffer_cnt(struct media_request *req); 1210 1211 #endif /* _MEDIA_VIDEOBUF2_CORE_H */ 1212