1/* 2 * videobuf2-v4l2.c - V4L2 driver helper framework 3 * 4 * Copyright (C) 2010 Samsung Electronics 5 * 6 * Author: Pawel Osciak <pawel@osciak.com> 7 * Marek Szyprowski <m.szyprowski@samsung.com> 8 * 9 * The vb2_thread implementation was based on code from videobuf-dvb.c: 10 * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs] 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation. 15 */ 16 17#include <linux/device.h> 18#include <linux/err.h> 19#include <linux/freezer.h> 20#include <linux/kernel.h> 21#include <linux/kthread.h> 22#include <linux/mm.h> 23#include <linux/module.h> 24#include <linux/poll.h> 25#include <linux/sched.h> 26#include <linux/slab.h> 27 28#include <media/v4l2-common.h> 29#include <media/v4l2-dev.h> 30#include <media/v4l2-device.h> 31#include <media/v4l2-event.h> 32#include <media/v4l2-fh.h> 33 34#include <media/videobuf2-v4l2.h> 35 36static int debug; 37module_param(debug, int, 0644); 38 39#define dprintk(q, level, fmt, arg...) \ 40 do { \ 41 if (debug >= level) \ 42 pr_info("vb2-v4l2: [%p] %s: " fmt, \ 43 (q)->name, __func__, ## arg); \ 44 } while (0) 45 46/* Flags that are set by us */ 47#define V4L2_BUFFER_MASK_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \ 48 V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \ 49 V4L2_BUF_FLAG_PREPARED | \ 50 V4L2_BUF_FLAG_IN_REQUEST | \ 51 V4L2_BUF_FLAG_REQUEST_FD | \ 52 V4L2_BUF_FLAG_TIMESTAMP_MASK) 53/* Output buffer flags that should be passed on to the driver */ 54#define V4L2_BUFFER_OUT_FLAGS (V4L2_BUF_FLAG_PFRAME | \ 55 V4L2_BUF_FLAG_BFRAME | \ 56 V4L2_BUF_FLAG_KEYFRAME | \ 57 V4L2_BUF_FLAG_TIMECODE | \ 58 V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF) 59 60/* 61 * __verify_planes_array() - verify that the planes array passed in struct 62 * v4l2_buffer from userspace can be safely used 63 */ 64static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b) 65{ 66 if (!V4L2_TYPE_IS_MULTIPLANAR(b->type)) 67 return 0; 68 69 /* Is memory for copying plane information present? */ 70 if (b->m.planes == NULL) { 71 dprintk(vb->vb2_queue, 1, 72 "multi-planar buffer passed but planes array not provided\n"); 73 return -EINVAL; 74 } 75 76 if (b->length < vb->num_planes || b->length > VB2_MAX_PLANES) { 77 dprintk(vb->vb2_queue, 1, 78 "incorrect planes array length, expected %d, got %d\n", 79 vb->num_planes, b->length); 80 return -EINVAL; 81 } 82 83 return 0; 84} 85 86static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb) 87{ 88 return __verify_planes_array(vb, pb); 89} 90 91/* 92 * __verify_length() - Verify that the bytesused value for each plane fits in 93 * the plane length and that the data offset doesn't exceed the bytesused value. 94 */ 95static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b) 96{ 97 unsigned int length; 98 unsigned int bytesused; 99 unsigned int plane; 100 101 if (V4L2_TYPE_IS_CAPTURE(b->type)) 102 return 0; 103 104 if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { 105 for (plane = 0; plane < vb->num_planes; ++plane) { 106 length = (b->memory == VB2_MEMORY_USERPTR || 107 b->memory == VB2_MEMORY_DMABUF) 108 ? b->m.planes[plane].length 109 : vb->planes[plane].length; 110 bytesused = b->m.planes[plane].bytesused 111 ? b->m.planes[plane].bytesused : length; 112 113 if (b->m.planes[plane].bytesused > length) 114 return -EINVAL; 115 116 if (b->m.planes[plane].data_offset > 0 && 117 b->m.planes[plane].data_offset >= bytesused) 118 return -EINVAL; 119 } 120 } else { 121 length = (b->memory == VB2_MEMORY_USERPTR) 122 ? b->length : vb->planes[0].length; 123 124 if (b->bytesused > length) 125 return -EINVAL; 126 } 127 128 return 0; 129} 130 131/* 132 * __init_vb2_v4l2_buffer() - initialize the vb2_v4l2_buffer struct 133 */ 134static void __init_vb2_v4l2_buffer(struct vb2_buffer *vb) 135{ 136 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 137 138 vbuf->request_fd = -1; 139} 140 141static void __copy_timestamp(struct vb2_buffer *vb, const void *pb) 142{ 143 const struct v4l2_buffer *b = pb; 144 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 145 struct vb2_queue *q = vb->vb2_queue; 146 147 if (q->is_output) { 148 /* 149 * For output buffers copy the timestamp if needed, 150 * and the timecode field and flag if needed. 151 */ 152 if (q->copy_timestamp) 153 vb->timestamp = v4l2_buffer_get_timestamp(b); 154 vbuf->flags |= b->flags & V4L2_BUF_FLAG_TIMECODE; 155 if (b->flags & V4L2_BUF_FLAG_TIMECODE) 156 vbuf->timecode = b->timecode; 157 } 158}; 159 160static void vb2_warn_zero_bytesused(struct vb2_buffer *vb) 161{ 162 static bool check_once; 163 164 if (check_once) 165 return; 166 167 check_once = true; 168 169 pr_warn("use of bytesused == 0 is deprecated and will be removed in the future,\n"); 170 if (vb->vb2_queue->allow_zero_bytesused) 171 pr_warn("use VIDIOC_DECODER_CMD(V4L2_DEC_CMD_STOP) instead.\n"); 172 else 173 pr_warn("use the actual size instead.\n"); 174} 175 176static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b) 177{ 178 struct vb2_queue *q = vb->vb2_queue; 179 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 180 struct vb2_plane *planes = vbuf->planes; 181 unsigned int plane; 182 int ret; 183 184 ret = __verify_length(vb, b); 185 if (ret < 0) { 186 dprintk(q, 1, "plane parameters verification failed: %d\n", ret); 187 return ret; 188 } 189 if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) { 190 /* 191 * If the format's field is ALTERNATE, then the buffer's field 192 * should be either TOP or BOTTOM, not ALTERNATE since that 193 * makes no sense. The driver has to know whether the 194 * buffer represents a top or a bottom field in order to 195 * program any DMA correctly. Using ALTERNATE is wrong, since 196 * that just says that it is either a top or a bottom field, 197 * but not which of the two it is. 198 */ 199 dprintk(q, 1, "the field is incorrectly set to ALTERNATE for an output buffer\n"); 200 return -EINVAL; 201 } 202 vbuf->sequence = 0; 203 vbuf->request_fd = -1; 204 vbuf->is_held = false; 205 206 if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { 207 switch (b->memory) { 208 case VB2_MEMORY_USERPTR: 209 for (plane = 0; plane < vb->num_planes; ++plane) { 210 planes[plane].m.userptr = 211 b->m.planes[plane].m.userptr; 212 planes[plane].length = 213 b->m.planes[plane].length; 214 } 215 break; 216 case VB2_MEMORY_DMABUF: 217 for (plane = 0; plane < vb->num_planes; ++plane) { 218 planes[plane].m.fd = 219 b->m.planes[plane].m.fd; 220 planes[plane].length = 221 b->m.planes[plane].length; 222 } 223 break; 224 default: 225 for (plane = 0; plane < vb->num_planes; ++plane) { 226 planes[plane].m.offset = 227 vb->planes[plane].m.offset; 228 planes[plane].length = 229 vb->planes[plane].length; 230 } 231 break; 232 } 233 234 /* Fill in driver-provided information for OUTPUT types */ 235 if (V4L2_TYPE_IS_OUTPUT(b->type)) { 236 /* 237 * Will have to go up to b->length when API starts 238 * accepting variable number of planes. 239 * 240 * If bytesused == 0 for the output buffer, then fall 241 * back to the full buffer size. In that case 242 * userspace clearly never bothered to set it and 243 * it's a safe assumption that they really meant to 244 * use the full plane sizes. 245 * 246 * Some drivers, e.g. old codec drivers, use bytesused == 0 247 * as a way to indicate that streaming is finished. 248 * In that case, the driver should use the 249 * allow_zero_bytesused flag to keep old userspace 250 * applications working. 251 */ 252 for (plane = 0; plane < vb->num_planes; ++plane) { 253 struct vb2_plane *pdst = &planes[plane]; 254 struct v4l2_plane *psrc = &b->m.planes[plane]; 255 256 if (psrc->bytesused == 0) 257 vb2_warn_zero_bytesused(vb); 258 259 if (vb->vb2_queue->allow_zero_bytesused) 260 pdst->bytesused = psrc->bytesused; 261 else 262 pdst->bytesused = psrc->bytesused ? 263 psrc->bytesused : pdst->length; 264 pdst->data_offset = psrc->data_offset; 265 } 266 } 267 } else { 268 /* 269 * Single-planar buffers do not use planes array, 270 * so fill in relevant v4l2_buffer struct fields instead. 271 * In vb2 we use our internal V4l2_planes struct for 272 * single-planar buffers as well, for simplicity. 273 * 274 * If bytesused == 0 for the output buffer, then fall back 275 * to the full buffer size as that's a sensible default. 276 * 277 * Some drivers, e.g. old codec drivers, use bytesused == 0 as 278 * a way to indicate that streaming is finished. In that case, 279 * the driver should use the allow_zero_bytesused flag to keep 280 * old userspace applications working. 281 */ 282 switch (b->memory) { 283 case VB2_MEMORY_USERPTR: 284 planes[0].m.userptr = b->m.userptr; 285 planes[0].length = b->length; 286 break; 287 case VB2_MEMORY_DMABUF: 288 planes[0].m.fd = b->m.fd; 289 planes[0].length = b->length; 290 break; 291 default: 292 planes[0].m.offset = vb->planes[0].m.offset; 293 planes[0].length = vb->planes[0].length; 294 break; 295 } 296 297 planes[0].data_offset = 0; 298 if (V4L2_TYPE_IS_OUTPUT(b->type)) { 299 if (b->bytesused == 0) 300 vb2_warn_zero_bytesused(vb); 301 302 if (vb->vb2_queue->allow_zero_bytesused) 303 planes[0].bytesused = b->bytesused; 304 else 305 planes[0].bytesused = b->bytesused ? 306 b->bytesused : planes[0].length; 307 } else 308 planes[0].bytesused = 0; 309 310 } 311 312 /* Zero flags that we handle */ 313 vbuf->flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS; 314 if (!vb->vb2_queue->copy_timestamp || V4L2_TYPE_IS_CAPTURE(b->type)) { 315 /* 316 * Non-COPY timestamps and non-OUTPUT queues will get 317 * their timestamp and timestamp source flags from the 318 * queue. 319 */ 320 vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; 321 } 322 323 if (V4L2_TYPE_IS_OUTPUT(b->type)) { 324 /* 325 * For output buffers mask out the timecode flag: 326 * this will be handled later in vb2_qbuf(). 327 * The 'field' is valid metadata for this output buffer 328 * and so that needs to be copied here. 329 */ 330 vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE; 331 vbuf->field = b->field; 332 if (!(q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF)) 333 vbuf->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF; 334 } else { 335 /* Zero any output buffer flags as this is a capture buffer */ 336 vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS; 337 /* Zero last flag, this is a signal from driver to userspace */ 338 vbuf->flags &= ~V4L2_BUF_FLAG_LAST; 339 } 340 341 return 0; 342} 343 344static void set_buffer_cache_hints(struct vb2_queue *q, 345 struct vb2_buffer *vb, 346 struct v4l2_buffer *b) 347{ 348 if (!vb2_queue_allows_cache_hints(q)) { 349 /* 350 * Clear buffer cache flags if queue does not support user 351 * space hints. That's to indicate to userspace that these 352 * flags won't work. 353 */ 354 b->flags &= ~V4L2_BUF_FLAG_NO_CACHE_INVALIDATE; 355 b->flags &= ~V4L2_BUF_FLAG_NO_CACHE_CLEAN; 356 return; 357 } 358 359 if (b->flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE) 360 vb->skip_cache_sync_on_finish = 1; 361 362 if (b->flags & V4L2_BUF_FLAG_NO_CACHE_CLEAN) 363 vb->skip_cache_sync_on_prepare = 1; 364} 365 366static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *mdev, 367 struct v4l2_buffer *b, bool is_prepare, 368 struct media_request **p_req) 369{ 370 const char *opname = is_prepare ? "prepare_buf" : "qbuf"; 371 struct media_request *req; 372 struct vb2_v4l2_buffer *vbuf; 373 struct vb2_buffer *vb; 374 int ret; 375 376 if (b->type != q->type) { 377 dprintk(q, 1, "%s: invalid buffer type\n", opname); 378 return -EINVAL; 379 } 380 381 if (b->index >= q->num_buffers) { 382 dprintk(q, 1, "%s: buffer index out of range\n", opname); 383 return -EINVAL; 384 } 385 386 if (q->bufs[b->index] == NULL) { 387 /* Should never happen */ 388 dprintk(q, 1, "%s: buffer is NULL\n", opname); 389 return -EINVAL; 390 } 391 392 if (b->memory != q->memory) { 393 dprintk(q, 1, "%s: invalid memory type\n", opname); 394 return -EINVAL; 395 } 396 397 vb = q->bufs[b->index]; 398 vbuf = to_vb2_v4l2_buffer(vb); 399 ret = __verify_planes_array(vb, b); 400 if (ret) 401 return ret; 402 403 if (!is_prepare && (b->flags & V4L2_BUF_FLAG_REQUEST_FD) && 404 vb->state != VB2_BUF_STATE_DEQUEUED) { 405 dprintk(q, 1, "%s: buffer is not in dequeued state\n", opname); 406 return -EINVAL; 407 } 408 409 if (!vb->prepared) { 410 set_buffer_cache_hints(q, vb, b); 411 /* Copy relevant information provided by the userspace */ 412 memset(vbuf->planes, 0, 413 sizeof(vbuf->planes[0]) * vb->num_planes); 414 ret = vb2_fill_vb2_v4l2_buffer(vb, b); 415 if (ret) 416 return ret; 417 } 418 419 if (is_prepare) 420 return 0; 421 422 if (!(b->flags & V4L2_BUF_FLAG_REQUEST_FD)) { 423 if (q->requires_requests) { 424 dprintk(q, 1, "%s: queue requires requests\n", opname); 425 return -EBADR; 426 } 427 if (q->uses_requests) { 428 dprintk(q, 1, "%s: queue uses requests\n", opname); 429 return -EBUSY; 430 } 431 return 0; 432 } else if (!q->supports_requests) { 433 dprintk(q, 1, "%s: queue does not support requests\n", opname); 434 return -EBADR; 435 } else if (q->uses_qbuf) { 436 dprintk(q, 1, "%s: queue does not use requests\n", opname); 437 return -EBUSY; 438 } 439 440 /* 441 * For proper locking when queueing a request you need to be able 442 * to lock access to the vb2 queue, so check that there is a lock 443 * that we can use. In addition p_req must be non-NULL. 444 */ 445 if (WARN_ON(!q->lock || !p_req)) 446 return -EINVAL; 447 448 /* 449 * Make sure this op is implemented by the driver. It's easy to forget 450 * this callback, but is it important when canceling a buffer in a 451 * queued request. 452 */ 453 if (WARN_ON(!q->ops->buf_request_complete)) 454 return -EINVAL; 455 /* 456 * Make sure this op is implemented by the driver for the output queue. 457 * It's easy to forget this callback, but is it important to correctly 458 * validate the 'field' value at QBUF time. 459 */ 460 if (WARN_ON((q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT || 461 q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) && 462 !q->ops->buf_out_validate)) 463 return -EINVAL; 464 465 req = media_request_get_by_fd(mdev, b->request_fd); 466 if (IS_ERR(req)) { 467 dprintk(q, 1, "%s: invalid request_fd\n", opname); 468 return PTR_ERR(req); 469 } 470 471 /* 472 * Early sanity check. This is checked again when the buffer 473 * is bound to the request in vb2_core_qbuf(). 474 */ 475 if (req->state != MEDIA_REQUEST_STATE_IDLE && 476 req->state != MEDIA_REQUEST_STATE_UPDATING) { 477 dprintk(q, 1, "%s: request is not idle\n", opname); 478 media_request_put(req); 479 return -EBUSY; 480 } 481 482 *p_req = req; 483 vbuf->request_fd = b->request_fd; 484 485 return 0; 486} 487 488/* 489 * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be 490 * returned to userspace 491 */ 492static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb) 493{ 494 struct v4l2_buffer *b = pb; 495 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 496 struct vb2_queue *q = vb->vb2_queue; 497 unsigned int plane; 498 499 /* Copy back data such as timestamp, flags, etc. */ 500 b->index = vb->index; 501 b->type = vb->type; 502 b->memory = vb->memory; 503 b->bytesused = 0; 504 505 b->flags = vbuf->flags; 506 b->field = vbuf->field; 507 v4l2_buffer_set_timestamp(b, vb->timestamp); 508 b->timecode = vbuf->timecode; 509 b->sequence = vbuf->sequence; 510 b->reserved2 = 0; 511 b->request_fd = 0; 512 513 if (q->is_multiplanar) { 514 /* 515 * Fill in plane-related data if userspace provided an array 516 * for it. The caller has already verified memory and size. 517 */ 518 b->length = vb->num_planes; 519 for (plane = 0; plane < vb->num_planes; ++plane) { 520 struct v4l2_plane *pdst = &b->m.planes[plane]; 521 struct vb2_plane *psrc = &vb->planes[plane]; 522 523 pdst->bytesused = psrc->bytesused; 524 pdst->length = psrc->length; 525 if (q->memory == VB2_MEMORY_MMAP) 526 pdst->m.mem_offset = psrc->m.offset; 527 else if (q->memory == VB2_MEMORY_USERPTR) 528 pdst->m.userptr = psrc->m.userptr; 529 else if (q->memory == VB2_MEMORY_DMABUF) 530 pdst->m.fd = psrc->m.fd; 531 pdst->data_offset = psrc->data_offset; 532 memset(pdst->reserved, 0, sizeof(pdst->reserved)); 533 } 534 } else { 535 /* 536 * We use length and offset in v4l2_planes array even for 537 * single-planar buffers, but userspace does not. 538 */ 539 b->length = vb->planes[0].length; 540 b->bytesused = vb->planes[0].bytesused; 541 if (q->memory == VB2_MEMORY_MMAP) 542 b->m.offset = vb->planes[0].m.offset; 543 else if (q->memory == VB2_MEMORY_USERPTR) 544 b->m.userptr = vb->planes[0].m.userptr; 545 else if (q->memory == VB2_MEMORY_DMABUF) 546 b->m.fd = vb->planes[0].m.fd; 547 } 548 549 /* 550 * Clear any buffer state related flags. 551 */ 552 b->flags &= ~V4L2_BUFFER_MASK_FLAGS; 553 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK; 554 if (!q->copy_timestamp) { 555 /* 556 * For non-COPY timestamps, drop timestamp source bits 557 * and obtain the timestamp source from the queue. 558 */ 559 b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; 560 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK; 561 } 562 563 switch (vb->state) { 564 case VB2_BUF_STATE_QUEUED: 565 case VB2_BUF_STATE_ACTIVE: 566 b->flags |= V4L2_BUF_FLAG_QUEUED; 567 break; 568 case VB2_BUF_STATE_IN_REQUEST: 569 b->flags |= V4L2_BUF_FLAG_IN_REQUEST; 570 break; 571 case VB2_BUF_STATE_ERROR: 572 b->flags |= V4L2_BUF_FLAG_ERROR; 573 fallthrough; 574 case VB2_BUF_STATE_DONE: 575 b->flags |= V4L2_BUF_FLAG_DONE; 576 break; 577 case VB2_BUF_STATE_PREPARING: 578 case VB2_BUF_STATE_DEQUEUED: 579 /* nothing */ 580 break; 581 } 582 583 if ((vb->state == VB2_BUF_STATE_DEQUEUED || 584 vb->state == VB2_BUF_STATE_IN_REQUEST) && 585 vb->synced && vb->prepared) 586 b->flags |= V4L2_BUF_FLAG_PREPARED; 587 588 if (vb2_buffer_in_use(q, vb)) 589 b->flags |= V4L2_BUF_FLAG_MAPPED; 590 if (vbuf->request_fd >= 0) { 591 b->flags |= V4L2_BUF_FLAG_REQUEST_FD; 592 b->request_fd = vbuf->request_fd; 593 } 594} 595 596/* 597 * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a 598 * v4l2_buffer by the userspace. It also verifies that struct 599 * v4l2_buffer has a valid number of planes. 600 */ 601static int __fill_vb2_buffer(struct vb2_buffer *vb, struct vb2_plane *planes) 602{ 603 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 604 unsigned int plane; 605 606 if (!vb->vb2_queue->copy_timestamp) 607 vb->timestamp = 0; 608 609 for (plane = 0; plane < vb->num_planes; ++plane) { 610 if (vb->vb2_queue->memory != VB2_MEMORY_MMAP) { 611 planes[plane].m = vbuf->planes[plane].m; 612 planes[plane].length = vbuf->planes[plane].length; 613 } 614 planes[plane].bytesused = vbuf->planes[plane].bytesused; 615 planes[plane].data_offset = vbuf->planes[plane].data_offset; 616 } 617 return 0; 618} 619 620static const struct vb2_buf_ops v4l2_buf_ops = { 621 .verify_planes_array = __verify_planes_array_core, 622 .init_buffer = __init_vb2_v4l2_buffer, 623 .fill_user_buffer = __fill_v4l2_buffer, 624 .fill_vb2_buffer = __fill_vb2_buffer, 625 .copy_timestamp = __copy_timestamp, 626}; 627 628struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp) 629{ 630 unsigned int i; 631 632 for (i = 0; i < q->num_buffers; i++) 633 if (q->bufs[i]->copied_timestamp && 634 q->bufs[i]->timestamp == timestamp) 635 return vb2_get_buffer(q, i); 636 return NULL; 637} 638EXPORT_SYMBOL_GPL(vb2_find_buffer); 639 640/* 641 * vb2_querybuf() - query video buffer information 642 * @q: vb2 queue 643 * @b: buffer struct passed from userspace to vidioc_querybuf handler 644 * in driver 645 * 646 * Should be called from vidioc_querybuf ioctl handler in driver. 647 * This function will verify the passed v4l2_buffer structure and fill the 648 * relevant information for the userspace. 649 * 650 * The return values from this function are intended to be directly returned 651 * from vidioc_querybuf handler in driver. 652 */ 653int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) 654{ 655 struct vb2_buffer *vb; 656 int ret; 657 658 if (b->type != q->type) { 659 dprintk(q, 1, "wrong buffer type\n"); 660 return -EINVAL; 661 } 662 663 if (b->index >= q->num_buffers) { 664 dprintk(q, 1, "buffer index out of range\n"); 665 return -EINVAL; 666 } 667 vb = q->bufs[b->index]; 668 ret = __verify_planes_array(vb, b); 669 if (!ret) 670 vb2_core_querybuf(q, b->index, b); 671 return ret; 672} 673EXPORT_SYMBOL(vb2_querybuf); 674 675static void fill_buf_caps(struct vb2_queue *q, u32 *caps) 676{ 677 *caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS; 678 if (q->io_modes & VB2_MMAP) 679 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP; 680 if (q->io_modes & VB2_USERPTR) 681 *caps |= V4L2_BUF_CAP_SUPPORTS_USERPTR; 682 if (q->io_modes & VB2_DMABUF) 683 *caps |= V4L2_BUF_CAP_SUPPORTS_DMABUF; 684 if (q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF) 685 *caps |= V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF; 686 if (q->allow_cache_hints && q->io_modes & VB2_MMAP) 687 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS; 688#ifdef CONFIG_MEDIA_CONTROLLER_REQUEST_API 689 if (q->supports_requests) 690 *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS; 691#endif 692} 693 694static void validate_memory_flags(struct vb2_queue *q, 695 int memory, 696 u32 *flags) 697{ 698 if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) { 699 /* 700 * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only, 701 * but in order to avoid bugs we zero out all bits. 702 */ 703 *flags = 0; 704 } else { 705 /* Clear all unknown flags. */ 706 *flags &= V4L2_MEMORY_FLAG_NON_COHERENT; 707 } 708} 709 710int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) 711{ 712 int ret = vb2_verify_memory_type(q, req->memory, req->type); 713 u32 flags = req->flags; 714 715 fill_buf_caps(q, &req->capabilities); 716 validate_memory_flags(q, req->memory, &flags); 717 req->flags = flags; 718 return ret ? ret : vb2_core_reqbufs(q, req->memory, 719 req->flags, &req->count); 720} 721EXPORT_SYMBOL_GPL(vb2_reqbufs); 722 723int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev, 724 struct v4l2_buffer *b) 725{ 726 int ret; 727 728 if (vb2_fileio_is_active(q)) { 729 dprintk(q, 1, "file io in progress\n"); 730 return -EBUSY; 731 } 732 733 if (b->flags & V4L2_BUF_FLAG_REQUEST_FD) 734 return -EINVAL; 735 736 ret = vb2_queue_or_prepare_buf(q, mdev, b, true, NULL); 737 738 return ret ? ret : vb2_core_prepare_buf(q, b->index, b); 739} 740EXPORT_SYMBOL_GPL(vb2_prepare_buf); 741 742int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) 743{ 744 unsigned requested_planes = 1; 745 unsigned requested_sizes[VIDEO_MAX_PLANES]; 746 struct v4l2_format *f = &create->format; 747 int ret = vb2_verify_memory_type(q, create->memory, f->type); 748 unsigned i; 749 750 fill_buf_caps(q, &create->capabilities); 751 validate_memory_flags(q, create->memory, &create->flags); 752 create->index = q->num_buffers; 753 if (create->count == 0) 754 return ret != -EBUSY ? ret : 0; 755 756 switch (f->type) { 757 case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: 758 case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: 759 requested_planes = f->fmt.pix_mp.num_planes; 760 if (requested_planes == 0 || 761 requested_planes > VIDEO_MAX_PLANES) 762 return -EINVAL; 763 for (i = 0; i < requested_planes; i++) 764 requested_sizes[i] = 765 f->fmt.pix_mp.plane_fmt[i].sizeimage; 766 break; 767 case V4L2_BUF_TYPE_VIDEO_CAPTURE: 768 case V4L2_BUF_TYPE_VIDEO_OUTPUT: 769 requested_sizes[0] = f->fmt.pix.sizeimage; 770 break; 771 case V4L2_BUF_TYPE_VBI_CAPTURE: 772 case V4L2_BUF_TYPE_VBI_OUTPUT: 773 requested_sizes[0] = f->fmt.vbi.samples_per_line * 774 (f->fmt.vbi.count[0] + f->fmt.vbi.count[1]); 775 break; 776 case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE: 777 case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT: 778 requested_sizes[0] = f->fmt.sliced.io_size; 779 break; 780 case V4L2_BUF_TYPE_SDR_CAPTURE: 781 case V4L2_BUF_TYPE_SDR_OUTPUT: 782 requested_sizes[0] = f->fmt.sdr.buffersize; 783 break; 784 case V4L2_BUF_TYPE_META_CAPTURE: 785 case V4L2_BUF_TYPE_META_OUTPUT: 786 requested_sizes[0] = f->fmt.meta.buffersize; 787 break; 788 default: 789 return -EINVAL; 790 } 791 for (i = 0; i < requested_planes; i++) 792 if (requested_sizes[i] == 0) 793 return -EINVAL; 794 return ret ? ret : vb2_core_create_bufs(q, create->memory, 795 create->flags, 796 &create->count, 797 requested_planes, 798 requested_sizes); 799} 800EXPORT_SYMBOL_GPL(vb2_create_bufs); 801 802int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev, 803 struct v4l2_buffer *b) 804{ 805 struct media_request *req = NULL; 806 int ret; 807 808 if (vb2_fileio_is_active(q)) { 809 dprintk(q, 1, "file io in progress\n"); 810 return -EBUSY; 811 } 812 813 ret = vb2_queue_or_prepare_buf(q, mdev, b, false, &req); 814 if (ret) 815 return ret; 816 ret = vb2_core_qbuf(q, b->index, b, req); 817 if (req) 818 media_request_put(req); 819 return ret; 820} 821EXPORT_SYMBOL_GPL(vb2_qbuf); 822 823int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) 824{ 825 int ret; 826 827 if (vb2_fileio_is_active(q)) { 828 dprintk(q, 1, "file io in progress\n"); 829 return -EBUSY; 830 } 831 832 if (b->type != q->type) { 833 dprintk(q, 1, "invalid buffer type\n"); 834 return -EINVAL; 835 } 836 837 ret = vb2_core_dqbuf(q, NULL, b, nonblocking); 838 839 if (!q->is_output && 840 b->flags & V4L2_BUF_FLAG_DONE && 841 b->flags & V4L2_BUF_FLAG_LAST) 842 q->last_buffer_dequeued = true; 843 844 /* 845 * After calling the VIDIOC_DQBUF V4L2_BUF_FLAG_DONE must be 846 * cleared. 847 */ 848 b->flags &= ~V4L2_BUF_FLAG_DONE; 849 850 return ret; 851} 852EXPORT_SYMBOL_GPL(vb2_dqbuf); 853 854int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) 855{ 856 if (vb2_fileio_is_active(q)) { 857 dprintk(q, 1, "file io in progress\n"); 858 return -EBUSY; 859 } 860 return vb2_core_streamon(q, type); 861} 862EXPORT_SYMBOL_GPL(vb2_streamon); 863 864int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) 865{ 866 if (vb2_fileio_is_active(q)) { 867 dprintk(q, 1, "file io in progress\n"); 868 return -EBUSY; 869 } 870 return vb2_core_streamoff(q, type); 871} 872EXPORT_SYMBOL_GPL(vb2_streamoff); 873 874int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) 875{ 876 return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index, 877 eb->plane, eb->flags); 878} 879EXPORT_SYMBOL_GPL(vb2_expbuf); 880 881int vb2_queue_init_name(struct vb2_queue *q, const char *name) 882{ 883 /* 884 * Sanity check 885 */ 886 if (WARN_ON(!q) || 887 WARN_ON(q->timestamp_flags & 888 ~(V4L2_BUF_FLAG_TIMESTAMP_MASK | 889 V4L2_BUF_FLAG_TSTAMP_SRC_MASK))) 890 return -EINVAL; 891 892 /* Warn that the driver should choose an appropriate timestamp type */ 893 WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == 894 V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN); 895 896 /* Warn that vb2_memory should match with v4l2_memory */ 897 if (WARN_ON(VB2_MEMORY_MMAP != (int)V4L2_MEMORY_MMAP) 898 || WARN_ON(VB2_MEMORY_USERPTR != (int)V4L2_MEMORY_USERPTR) 899 || WARN_ON(VB2_MEMORY_DMABUF != (int)V4L2_MEMORY_DMABUF)) 900 return -EINVAL; 901 902 if (q->buf_struct_size == 0) 903 q->buf_struct_size = sizeof(struct vb2_v4l2_buffer); 904 905 q->buf_ops = &v4l2_buf_ops; 906 q->is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type); 907 q->is_output = V4L2_TYPE_IS_OUTPUT(q->type); 908 q->copy_timestamp = (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) 909 == V4L2_BUF_FLAG_TIMESTAMP_COPY; 910 /* 911 * For compatibility with vb1: if QBUF hasn't been called yet, then 912 * return EPOLLERR as well. This only affects capture queues, output 913 * queues will always initialize waiting_for_buffers to false. 914 */ 915 q->quirk_poll_must_check_waiting_for_buffers = true; 916 917 if (name) 918 strscpy(q->name, name, sizeof(q->name)); 919 else 920 q->name[0] = '\0'; 921 922 return vb2_core_queue_init(q); 923} 924EXPORT_SYMBOL_GPL(vb2_queue_init_name); 925 926int vb2_queue_init(struct vb2_queue *q) 927{ 928 return vb2_queue_init_name(q, NULL); 929} 930EXPORT_SYMBOL_GPL(vb2_queue_init); 931 932void vb2_queue_release(struct vb2_queue *q) 933{ 934 vb2_core_queue_release(q); 935} 936EXPORT_SYMBOL_GPL(vb2_queue_release); 937 938int vb2_queue_change_type(struct vb2_queue *q, unsigned int type) 939{ 940 if (type == q->type) 941 return 0; 942 943 if (vb2_is_busy(q)) 944 return -EBUSY; 945 946 q->type = type; 947 948 return 0; 949} 950EXPORT_SYMBOL_GPL(vb2_queue_change_type); 951 952__poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) 953{ 954 struct video_device *vfd = video_devdata(file); 955 __poll_t res; 956 957 res = vb2_core_poll(q, file, wait); 958 959 if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { 960 struct v4l2_fh *fh = file->private_data; 961 962 poll_wait(file, &fh->wait, wait); 963 if (v4l2_event_pending(fh)) 964 res |= EPOLLPRI; 965 } 966 967 return res; 968} 969EXPORT_SYMBOL_GPL(vb2_poll); 970 971/* 972 * The following functions are not part of the vb2 core API, but are helper 973 * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations 974 * and struct vb2_ops. 975 * They contain boilerplate code that most if not all drivers have to do 976 * and so they simplify the driver code. 977 */ 978 979/* vb2 ioctl helpers */ 980 981int vb2_ioctl_reqbufs(struct file *file, void *priv, 982 struct v4l2_requestbuffers *p) 983{ 984 struct video_device *vdev = video_devdata(file); 985 int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); 986 u32 flags = p->flags; 987 988 fill_buf_caps(vdev->queue, &p->capabilities); 989 validate_memory_flags(vdev->queue, p->memory, &flags); 990 p->flags = flags; 991 if (res) 992 return res; 993 if (vb2_queue_is_busy(vdev->queue, file)) 994 return -EBUSY; 995 res = vb2_core_reqbufs(vdev->queue, p->memory, p->flags, &p->count); 996 /* If count == 0, then the owner has released all buffers and he 997 is no longer owner of the queue. Otherwise we have a new owner. */ 998 if (res == 0) 999 vdev->queue->owner = p->count ? file->private_data : NULL; 1000 return res; 1001} 1002EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs); 1003 1004int vb2_ioctl_create_bufs(struct file *file, void *priv, 1005 struct v4l2_create_buffers *p) 1006{ 1007 struct video_device *vdev = video_devdata(file); 1008 int res = vb2_verify_memory_type(vdev->queue, p->memory, 1009 p->format.type); 1010 1011 p->index = vdev->queue->num_buffers; 1012 fill_buf_caps(vdev->queue, &p->capabilities); 1013 validate_memory_flags(vdev->queue, p->memory, &p->flags); 1014 /* 1015 * If count == 0, then just check if memory and type are valid. 1016 * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0. 1017 */ 1018 if (p->count == 0) 1019 return res != -EBUSY ? res : 0; 1020 if (res) 1021 return res; 1022 if (vb2_queue_is_busy(vdev->queue, file)) 1023 return -EBUSY; 1024 1025 res = vb2_create_bufs(vdev->queue, p); 1026 if (res == 0) 1027 vdev->queue->owner = file->private_data; 1028 return res; 1029} 1030EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs); 1031 1032int vb2_ioctl_prepare_buf(struct file *file, void *priv, 1033 struct v4l2_buffer *p) 1034{ 1035 struct video_device *vdev = video_devdata(file); 1036 1037 if (vb2_queue_is_busy(vdev->queue, file)) 1038 return -EBUSY; 1039 return vb2_prepare_buf(vdev->queue, vdev->v4l2_dev->mdev, p); 1040} 1041EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf); 1042 1043int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p) 1044{ 1045 struct video_device *vdev = video_devdata(file); 1046 1047 /* No need to call vb2_queue_is_busy(), anyone can query buffers. */ 1048 return vb2_querybuf(vdev->queue, p); 1049} 1050EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf); 1051 1052int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p) 1053{ 1054 struct video_device *vdev = video_devdata(file); 1055 1056 if (vb2_queue_is_busy(vdev->queue, file)) 1057 return -EBUSY; 1058 return vb2_qbuf(vdev->queue, vdev->v4l2_dev->mdev, p); 1059} 1060EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf); 1061 1062int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p) 1063{ 1064 struct video_device *vdev = video_devdata(file); 1065 1066 if (vb2_queue_is_busy(vdev->queue, file)) 1067 return -EBUSY; 1068 return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK); 1069} 1070EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf); 1071 1072int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i) 1073{ 1074 struct video_device *vdev = video_devdata(file); 1075 1076 if (vb2_queue_is_busy(vdev->queue, file)) 1077 return -EBUSY; 1078 return vb2_streamon(vdev->queue, i); 1079} 1080EXPORT_SYMBOL_GPL(vb2_ioctl_streamon); 1081 1082int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) 1083{ 1084 struct video_device *vdev = video_devdata(file); 1085 1086 if (vb2_queue_is_busy(vdev->queue, file)) 1087 return -EBUSY; 1088 return vb2_streamoff(vdev->queue, i); 1089} 1090EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff); 1091 1092int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p) 1093{ 1094 struct video_device *vdev = video_devdata(file); 1095 1096 if (vb2_queue_is_busy(vdev->queue, file)) 1097 return -EBUSY; 1098 return vb2_expbuf(vdev->queue, p); 1099} 1100EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf); 1101 1102/* v4l2_file_operations helpers */ 1103 1104int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma) 1105{ 1106 struct video_device *vdev = video_devdata(file); 1107 1108 return vb2_mmap(vdev->queue, vma); 1109} 1110EXPORT_SYMBOL_GPL(vb2_fop_mmap); 1111 1112int _vb2_fop_release(struct file *file, struct mutex *lock) 1113{ 1114 struct video_device *vdev = video_devdata(file); 1115 1116 if (lock) 1117 mutex_lock(lock); 1118 if (file->private_data == vdev->queue->owner) { 1119 vb2_queue_release(vdev->queue); 1120 vdev->queue->owner = NULL; 1121 } 1122 if (lock) 1123 mutex_unlock(lock); 1124 return v4l2_fh_release(file); 1125} 1126EXPORT_SYMBOL_GPL(_vb2_fop_release); 1127 1128int vb2_fop_release(struct file *file) 1129{ 1130 struct video_device *vdev = video_devdata(file); 1131 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; 1132 1133 return _vb2_fop_release(file, lock); 1134} 1135EXPORT_SYMBOL_GPL(vb2_fop_release); 1136 1137ssize_t vb2_fop_write(struct file *file, const char __user *buf, 1138 size_t count, loff_t *ppos) 1139{ 1140 struct video_device *vdev = video_devdata(file); 1141 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; 1142 int err = -EBUSY; 1143 1144 if (!(vdev->queue->io_modes & VB2_WRITE)) 1145 return -EINVAL; 1146 if (lock && mutex_lock_interruptible(lock)) 1147 return -ERESTARTSYS; 1148 if (vb2_queue_is_busy(vdev->queue, file)) 1149 goto exit; 1150 err = vb2_write(vdev->queue, buf, count, ppos, 1151 file->f_flags & O_NONBLOCK); 1152 if (vdev->queue->fileio) 1153 vdev->queue->owner = file->private_data; 1154exit: 1155 if (lock) 1156 mutex_unlock(lock); 1157 return err; 1158} 1159EXPORT_SYMBOL_GPL(vb2_fop_write); 1160 1161ssize_t vb2_fop_read(struct file *file, char __user *buf, 1162 size_t count, loff_t *ppos) 1163{ 1164 struct video_device *vdev = video_devdata(file); 1165 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; 1166 int err = -EBUSY; 1167 1168 if (!(vdev->queue->io_modes & VB2_READ)) 1169 return -EINVAL; 1170 if (lock && mutex_lock_interruptible(lock)) 1171 return -ERESTARTSYS; 1172 if (vb2_queue_is_busy(vdev->queue, file)) 1173 goto exit; 1174 vdev->queue->owner = file->private_data; 1175 err = vb2_read(vdev->queue, buf, count, ppos, 1176 file->f_flags & O_NONBLOCK); 1177 if (!vdev->queue->fileio) 1178 vdev->queue->owner = NULL; 1179exit: 1180 if (lock) 1181 mutex_unlock(lock); 1182 return err; 1183} 1184EXPORT_SYMBOL_GPL(vb2_fop_read); 1185 1186__poll_t vb2_fop_poll(struct file *file, poll_table *wait) 1187{ 1188 struct video_device *vdev = video_devdata(file); 1189 struct vb2_queue *q = vdev->queue; 1190 struct mutex *lock = q->lock ? q->lock : vdev->lock; 1191 __poll_t res; 1192 void *fileio; 1193 1194 /* 1195 * If this helper doesn't know how to lock, then you shouldn't be using 1196 * it but you should write your own. 1197 */ 1198 WARN_ON(!lock); 1199 1200 if (lock && mutex_lock_interruptible(lock)) 1201 return EPOLLERR; 1202 1203 fileio = q->fileio; 1204 1205 res = vb2_poll(vdev->queue, file, wait); 1206 1207 /* If fileio was started, then we have a new queue owner. */ 1208 if (!fileio && q->fileio) 1209 q->owner = file->private_data; 1210 if (lock) 1211 mutex_unlock(lock); 1212 return res; 1213} 1214EXPORT_SYMBOL_GPL(vb2_fop_poll); 1215 1216#ifndef CONFIG_MMU 1217unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr, 1218 unsigned long len, unsigned long pgoff, unsigned long flags) 1219{ 1220 struct video_device *vdev = video_devdata(file); 1221 1222 return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags); 1223} 1224EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area); 1225#endif 1226 1227void vb2_video_unregister_device(struct video_device *vdev) 1228{ 1229 /* Check if vdev was ever registered at all */ 1230 if (!vdev || !video_is_registered(vdev)) 1231 return; 1232 1233 /* 1234 * Calling this function only makes sense if vdev->queue is set. 1235 * If it is NULL, then just call video_unregister_device() instead. 1236 */ 1237 WARN_ON(!vdev->queue); 1238 1239 /* 1240 * Take a reference to the device since video_unregister_device() 1241 * calls device_unregister(), but we don't want that to release 1242 * the device since we want to clean up the queue first. 1243 */ 1244 get_device(&vdev->dev); 1245 video_unregister_device(vdev); 1246 if (vdev->queue && vdev->queue->owner) { 1247 struct mutex *lock = vdev->queue->lock ? 1248 vdev->queue->lock : vdev->lock; 1249 1250 if (lock) 1251 mutex_lock(lock); 1252 vb2_queue_release(vdev->queue); 1253 vdev->queue->owner = NULL; 1254 if (lock) 1255 mutex_unlock(lock); 1256 } 1257 /* 1258 * Now we put the device, and in most cases this will release 1259 * everything. 1260 */ 1261 put_device(&vdev->dev); 1262} 1263EXPORT_SYMBOL_GPL(vb2_video_unregister_device); 1264 1265/* vb2_ops helpers. Only use if vq->lock is non-NULL. */ 1266 1267void vb2_ops_wait_prepare(struct vb2_queue *vq) 1268{ 1269 mutex_unlock(vq->lock); 1270} 1271EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare); 1272 1273void vb2_ops_wait_finish(struct vb2_queue *vq) 1274{ 1275 mutex_lock(vq->lock); 1276} 1277EXPORT_SYMBOL_GPL(vb2_ops_wait_finish); 1278 1279/* 1280 * Note that this function is called during validation time and 1281 * thus the req_queue_mutex is held to ensure no request objects 1282 * can be added or deleted while validating. So there is no need 1283 * to protect the objects list. 1284 */ 1285int vb2_request_validate(struct media_request *req) 1286{ 1287 struct media_request_object *obj; 1288 int ret = 0; 1289 1290 if (!vb2_request_buffer_cnt(req)) 1291 return -ENOENT; 1292 1293 list_for_each_entry(obj, &req->objects, list) { 1294 if (!obj->ops->prepare) 1295 continue; 1296 1297 ret = obj->ops->prepare(obj); 1298 if (ret) 1299 break; 1300 } 1301 1302 if (ret) { 1303 list_for_each_entry_continue_reverse(obj, &req->objects, list) 1304 if (obj->ops->unprepare) 1305 obj->ops->unprepare(obj); 1306 return ret; 1307 } 1308 return 0; 1309} 1310EXPORT_SYMBOL_GPL(vb2_request_validate); 1311 1312void vb2_request_queue(struct media_request *req) 1313{ 1314 struct media_request_object *obj, *obj_safe; 1315 1316 /* 1317 * Queue all objects. Note that buffer objects are at the end of the 1318 * objects list, after all other object types. Once buffer objects 1319 * are queued, the driver might delete them immediately (if the driver 1320 * processes the buffer at once), so we have to use 1321 * list_for_each_entry_safe() to handle the case where the object we 1322 * queue is deleted. 1323 */ 1324 list_for_each_entry_safe(obj, obj_safe, &req->objects, list) 1325 if (obj->ops->queue) 1326 obj->ops->queue(obj); 1327} 1328EXPORT_SYMBOL_GPL(vb2_request_queue); 1329 1330MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); 1331MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); 1332MODULE_LICENSE("GPL"); 1333