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 36 static int debug; 37 module_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 */ 64 static 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 86 static 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 */ 95 static 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 */ 134 static 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 } 140 141 static 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 }; 159 160 static 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 } 175 176 static 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 } 343 344 static 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 } 365 366 static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *mdev, 367 struct vb2_buffer *vb, struct v4l2_buffer *b, 368 bool is_prepare, 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 int ret; 374 375 if (b->type != q->type) { 376 dprintk(q, 1, "%s: invalid buffer type\n", opname); 377 return -EINVAL; 378 } 379 380 if (b->memory != q->memory) { 381 dprintk(q, 1, "%s: invalid memory type\n", opname); 382 return -EINVAL; 383 } 384 385 vbuf = to_vb2_v4l2_buffer(vb); 386 ret = __verify_planes_array(vb, b); 387 if (ret) 388 return ret; 389 390 if (!is_prepare && (b->flags & V4L2_BUF_FLAG_REQUEST_FD) && 391 vb->state != VB2_BUF_STATE_DEQUEUED) { 392 dprintk(q, 1, "%s: buffer is not in dequeued state\n", opname); 393 return -EINVAL; 394 } 395 396 if (!vb->prepared) { 397 set_buffer_cache_hints(q, vb, b); 398 /* Copy relevant information provided by the userspace */ 399 memset(vbuf->planes, 0, 400 sizeof(vbuf->planes[0]) * vb->num_planes); 401 ret = vb2_fill_vb2_v4l2_buffer(vb, b); 402 if (ret) 403 return ret; 404 } 405 406 if (is_prepare) 407 return 0; 408 409 if (!(b->flags & V4L2_BUF_FLAG_REQUEST_FD)) { 410 if (q->requires_requests) { 411 dprintk(q, 1, "%s: queue requires requests\n", opname); 412 return -EBADR; 413 } 414 if (q->uses_requests) { 415 dprintk(q, 1, "%s: queue uses requests\n", opname); 416 return -EBUSY; 417 } 418 return 0; 419 } else if (!q->supports_requests) { 420 dprintk(q, 1, "%s: queue does not support requests\n", opname); 421 return -EBADR; 422 } else if (q->uses_qbuf) { 423 dprintk(q, 1, "%s: queue does not use requests\n", opname); 424 return -EBUSY; 425 } 426 427 /* 428 * For proper locking when queueing a request you need to be able 429 * to lock access to the vb2 queue, so check that there is a lock 430 * that we can use. In addition p_req must be non-NULL. 431 */ 432 if (WARN_ON(!q->lock || !p_req)) 433 return -EINVAL; 434 435 /* 436 * Make sure this op is implemented by the driver. It's easy to forget 437 * this callback, but is it important when canceling a buffer in a 438 * queued request. 439 */ 440 if (WARN_ON(!q->ops->buf_request_complete)) 441 return -EINVAL; 442 /* 443 * Make sure this op is implemented by the driver for the output queue. 444 * It's easy to forget this callback, but is it important to correctly 445 * validate the 'field' value at QBUF time. 446 */ 447 if (WARN_ON((q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT || 448 q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) && 449 !q->ops->buf_out_validate)) 450 return -EINVAL; 451 452 req = media_request_get_by_fd(mdev, b->request_fd); 453 if (IS_ERR(req)) { 454 dprintk(q, 1, "%s: invalid request_fd\n", opname); 455 return PTR_ERR(req); 456 } 457 458 /* 459 * Early sanity check. This is checked again when the buffer 460 * is bound to the request in vb2_core_qbuf(). 461 */ 462 if (req->state != MEDIA_REQUEST_STATE_IDLE && 463 req->state != MEDIA_REQUEST_STATE_UPDATING) { 464 dprintk(q, 1, "%s: request is not idle\n", opname); 465 media_request_put(req); 466 return -EBUSY; 467 } 468 469 *p_req = req; 470 vbuf->request_fd = b->request_fd; 471 472 return 0; 473 } 474 475 /* 476 * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be 477 * returned to userspace 478 */ 479 static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb) 480 { 481 struct v4l2_buffer *b = pb; 482 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 483 struct vb2_queue *q = vb->vb2_queue; 484 unsigned int plane; 485 486 /* Copy back data such as timestamp, flags, etc. */ 487 b->index = vb->index; 488 b->type = vb->type; 489 b->memory = vb->memory; 490 b->bytesused = 0; 491 492 b->flags = vbuf->flags; 493 b->field = vbuf->field; 494 v4l2_buffer_set_timestamp(b, vb->timestamp); 495 b->timecode = vbuf->timecode; 496 b->sequence = vbuf->sequence; 497 b->reserved2 = 0; 498 b->request_fd = 0; 499 500 if (q->is_multiplanar) { 501 /* 502 * Fill in plane-related data if userspace provided an array 503 * for it. The caller has already verified memory and size. 504 */ 505 b->length = vb->num_planes; 506 for (plane = 0; plane < vb->num_planes; ++plane) { 507 struct v4l2_plane *pdst = &b->m.planes[plane]; 508 struct vb2_plane *psrc = &vb->planes[plane]; 509 510 pdst->bytesused = psrc->bytesused; 511 pdst->length = psrc->length; 512 if (q->memory == VB2_MEMORY_MMAP) 513 pdst->m.mem_offset = psrc->m.offset; 514 else if (q->memory == VB2_MEMORY_USERPTR) 515 pdst->m.userptr = psrc->m.userptr; 516 else if (q->memory == VB2_MEMORY_DMABUF) 517 pdst->m.fd = psrc->m.fd; 518 pdst->data_offset = psrc->data_offset; 519 memset(pdst->reserved, 0, sizeof(pdst->reserved)); 520 } 521 } else { 522 /* 523 * We use length and offset in v4l2_planes array even for 524 * single-planar buffers, but userspace does not. 525 */ 526 b->length = vb->planes[0].length; 527 b->bytesused = vb->planes[0].bytesused; 528 if (q->memory == VB2_MEMORY_MMAP) 529 b->m.offset = vb->planes[0].m.offset; 530 else if (q->memory == VB2_MEMORY_USERPTR) 531 b->m.userptr = vb->planes[0].m.userptr; 532 else if (q->memory == VB2_MEMORY_DMABUF) 533 b->m.fd = vb->planes[0].m.fd; 534 } 535 536 /* 537 * Clear any buffer state related flags. 538 */ 539 b->flags &= ~V4L2_BUFFER_MASK_FLAGS; 540 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK; 541 if (!q->copy_timestamp) { 542 /* 543 * For non-COPY timestamps, drop timestamp source bits 544 * and obtain the timestamp source from the queue. 545 */ 546 b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; 547 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK; 548 } 549 550 switch (vb->state) { 551 case VB2_BUF_STATE_QUEUED: 552 case VB2_BUF_STATE_ACTIVE: 553 b->flags |= V4L2_BUF_FLAG_QUEUED; 554 break; 555 case VB2_BUF_STATE_IN_REQUEST: 556 b->flags |= V4L2_BUF_FLAG_IN_REQUEST; 557 break; 558 case VB2_BUF_STATE_ERROR: 559 b->flags |= V4L2_BUF_FLAG_ERROR; 560 fallthrough; 561 case VB2_BUF_STATE_DONE: 562 b->flags |= V4L2_BUF_FLAG_DONE; 563 break; 564 case VB2_BUF_STATE_PREPARING: 565 case VB2_BUF_STATE_DEQUEUED: 566 /* nothing */ 567 break; 568 } 569 570 if ((vb->state == VB2_BUF_STATE_DEQUEUED || 571 vb->state == VB2_BUF_STATE_IN_REQUEST) && 572 vb->synced && vb->prepared) 573 b->flags |= V4L2_BUF_FLAG_PREPARED; 574 575 if (vb2_buffer_in_use(q, vb)) 576 b->flags |= V4L2_BUF_FLAG_MAPPED; 577 if (vbuf->request_fd >= 0) { 578 b->flags |= V4L2_BUF_FLAG_REQUEST_FD; 579 b->request_fd = vbuf->request_fd; 580 } 581 } 582 583 /* 584 * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a 585 * v4l2_buffer by the userspace. It also verifies that struct 586 * v4l2_buffer has a valid number of planes. 587 */ 588 static int __fill_vb2_buffer(struct vb2_buffer *vb, struct vb2_plane *planes) 589 { 590 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 591 unsigned int plane; 592 593 if (!vb->vb2_queue->copy_timestamp) 594 vb->timestamp = 0; 595 596 for (plane = 0; plane < vb->num_planes; ++plane) { 597 if (vb->vb2_queue->memory != VB2_MEMORY_MMAP) { 598 planes[plane].m = vbuf->planes[plane].m; 599 planes[plane].length = vbuf->planes[plane].length; 600 } 601 planes[plane].bytesused = vbuf->planes[plane].bytesused; 602 planes[plane].data_offset = vbuf->planes[plane].data_offset; 603 } 604 return 0; 605 } 606 607 static const struct vb2_buf_ops v4l2_buf_ops = { 608 .verify_planes_array = __verify_planes_array_core, 609 .init_buffer = __init_vb2_v4l2_buffer, 610 .fill_user_buffer = __fill_v4l2_buffer, 611 .fill_vb2_buffer = __fill_vb2_buffer, 612 .copy_timestamp = __copy_timestamp, 613 }; 614 615 struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp) 616 { 617 unsigned int i; 618 619 for (i = 0; i < q->num_buffers; i++) 620 if (q->bufs[i]->copied_timestamp && 621 q->bufs[i]->timestamp == timestamp) 622 return vb2_get_buffer(q, i); 623 return NULL; 624 } 625 EXPORT_SYMBOL_GPL(vb2_find_buffer); 626 627 /* 628 * vb2_querybuf() - query video buffer information 629 * @q: vb2 queue 630 * @b: buffer struct passed from userspace to vidioc_querybuf handler 631 * in driver 632 * 633 * Should be called from vidioc_querybuf ioctl handler in driver. 634 * This function will verify the passed v4l2_buffer structure and fill the 635 * relevant information for the userspace. 636 * 637 * The return values from this function are intended to be directly returned 638 * from vidioc_querybuf handler in driver. 639 */ 640 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) 641 { 642 struct vb2_buffer *vb; 643 int ret; 644 645 if (b->type != q->type) { 646 dprintk(q, 1, "wrong buffer type\n"); 647 return -EINVAL; 648 } 649 650 if (b->index >= q->num_buffers) { 651 dprintk(q, 1, "buffer index out of range\n"); 652 return -EINVAL; 653 } 654 vb = q->bufs[b->index]; 655 ret = __verify_planes_array(vb, b); 656 if (!ret) 657 vb2_core_querybuf(q, vb, b); 658 return ret; 659 } 660 EXPORT_SYMBOL(vb2_querybuf); 661 662 static void fill_buf_caps(struct vb2_queue *q, u32 *caps) 663 { 664 *caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS; 665 if (q->io_modes & VB2_MMAP) 666 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP; 667 if (q->io_modes & VB2_USERPTR) 668 *caps |= V4L2_BUF_CAP_SUPPORTS_USERPTR; 669 if (q->io_modes & VB2_DMABUF) 670 *caps |= V4L2_BUF_CAP_SUPPORTS_DMABUF; 671 if (q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF) 672 *caps |= V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF; 673 if (q->allow_cache_hints && q->io_modes & VB2_MMAP) 674 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS; 675 #ifdef CONFIG_MEDIA_CONTROLLER_REQUEST_API 676 if (q->supports_requests) 677 *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS; 678 #endif 679 } 680 681 static void validate_memory_flags(struct vb2_queue *q, 682 int memory, 683 u32 *flags) 684 { 685 if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) { 686 /* 687 * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only, 688 * but in order to avoid bugs we zero out all bits. 689 */ 690 *flags = 0; 691 } else { 692 /* Clear all unknown flags. */ 693 *flags &= V4L2_MEMORY_FLAG_NON_COHERENT; 694 } 695 } 696 697 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) 698 { 699 int ret = vb2_verify_memory_type(q, req->memory, req->type); 700 u32 flags = req->flags; 701 702 fill_buf_caps(q, &req->capabilities); 703 validate_memory_flags(q, req->memory, &flags); 704 req->flags = flags; 705 return ret ? ret : vb2_core_reqbufs(q, req->memory, 706 req->flags, &req->count); 707 } 708 EXPORT_SYMBOL_GPL(vb2_reqbufs); 709 710 int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev, 711 struct v4l2_buffer *b) 712 { 713 struct vb2_buffer *vb; 714 int ret; 715 716 if (vb2_fileio_is_active(q)) { 717 dprintk(q, 1, "file io in progress\n"); 718 return -EBUSY; 719 } 720 721 if (b->flags & V4L2_BUF_FLAG_REQUEST_FD) 722 return -EINVAL; 723 724 if (b->index >= q->num_buffers) { 725 dprintk(q, 1, "buffer index out of range\n"); 726 return -EINVAL; 727 } 728 vb = q->bufs[b->index]; 729 730 ret = vb2_queue_or_prepare_buf(q, mdev, vb, b, true, NULL); 731 732 return ret ? ret : vb2_core_prepare_buf(q, vb, b); 733 } 734 EXPORT_SYMBOL_GPL(vb2_prepare_buf); 735 736 int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) 737 { 738 unsigned requested_planes = 1; 739 unsigned requested_sizes[VIDEO_MAX_PLANES]; 740 struct v4l2_format *f = &create->format; 741 int ret = vb2_verify_memory_type(q, create->memory, f->type); 742 unsigned i; 743 744 fill_buf_caps(q, &create->capabilities); 745 validate_memory_flags(q, create->memory, &create->flags); 746 create->index = q->num_buffers; 747 if (create->count == 0) 748 return ret != -EBUSY ? ret : 0; 749 750 switch (f->type) { 751 case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: 752 case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: 753 requested_planes = f->fmt.pix_mp.num_planes; 754 if (requested_planes == 0 || 755 requested_planes > VIDEO_MAX_PLANES) 756 return -EINVAL; 757 for (i = 0; i < requested_planes; i++) 758 requested_sizes[i] = 759 f->fmt.pix_mp.plane_fmt[i].sizeimage; 760 break; 761 case V4L2_BUF_TYPE_VIDEO_CAPTURE: 762 case V4L2_BUF_TYPE_VIDEO_OUTPUT: 763 requested_sizes[0] = f->fmt.pix.sizeimage; 764 break; 765 case V4L2_BUF_TYPE_VBI_CAPTURE: 766 case V4L2_BUF_TYPE_VBI_OUTPUT: 767 requested_sizes[0] = f->fmt.vbi.samples_per_line * 768 (f->fmt.vbi.count[0] + f->fmt.vbi.count[1]); 769 break; 770 case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE: 771 case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT: 772 requested_sizes[0] = f->fmt.sliced.io_size; 773 break; 774 case V4L2_BUF_TYPE_SDR_CAPTURE: 775 case V4L2_BUF_TYPE_SDR_OUTPUT: 776 requested_sizes[0] = f->fmt.sdr.buffersize; 777 break; 778 case V4L2_BUF_TYPE_META_CAPTURE: 779 case V4L2_BUF_TYPE_META_OUTPUT: 780 requested_sizes[0] = f->fmt.meta.buffersize; 781 break; 782 default: 783 return -EINVAL; 784 } 785 for (i = 0; i < requested_planes; i++) 786 if (requested_sizes[i] == 0) 787 return -EINVAL; 788 return ret ? ret : vb2_core_create_bufs(q, create->memory, 789 create->flags, 790 &create->count, 791 requested_planes, 792 requested_sizes); 793 } 794 EXPORT_SYMBOL_GPL(vb2_create_bufs); 795 796 int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev, 797 struct v4l2_buffer *b) 798 { 799 struct media_request *req = NULL; 800 struct vb2_buffer *vb; 801 int ret; 802 803 if (vb2_fileio_is_active(q)) { 804 dprintk(q, 1, "file io in progress\n"); 805 return -EBUSY; 806 } 807 808 if (b->index >= q->num_buffers) { 809 dprintk(q, 1, "buffer index out of range\n"); 810 return -EINVAL; 811 } 812 vb = q->bufs[b->index]; 813 814 ret = vb2_queue_or_prepare_buf(q, mdev, vb, b, false, &req); 815 if (ret) 816 return ret; 817 ret = vb2_core_qbuf(q, vb, b, req); 818 if (req) 819 media_request_put(req); 820 return ret; 821 } 822 EXPORT_SYMBOL_GPL(vb2_qbuf); 823 824 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) 825 { 826 int ret; 827 828 if (vb2_fileio_is_active(q)) { 829 dprintk(q, 1, "file io in progress\n"); 830 return -EBUSY; 831 } 832 833 if (b->type != q->type) { 834 dprintk(q, 1, "invalid buffer type\n"); 835 return -EINVAL; 836 } 837 838 ret = vb2_core_dqbuf(q, NULL, b, nonblocking); 839 840 if (!q->is_output && 841 b->flags & V4L2_BUF_FLAG_DONE && 842 b->flags & V4L2_BUF_FLAG_LAST) 843 q->last_buffer_dequeued = true; 844 845 /* 846 * After calling the VIDIOC_DQBUF V4L2_BUF_FLAG_DONE must be 847 * cleared. 848 */ 849 b->flags &= ~V4L2_BUF_FLAG_DONE; 850 851 return ret; 852 } 853 EXPORT_SYMBOL_GPL(vb2_dqbuf); 854 855 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) 856 { 857 if (vb2_fileio_is_active(q)) { 858 dprintk(q, 1, "file io in progress\n"); 859 return -EBUSY; 860 } 861 return vb2_core_streamon(q, type); 862 } 863 EXPORT_SYMBOL_GPL(vb2_streamon); 864 865 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) 866 { 867 if (vb2_fileio_is_active(q)) { 868 dprintk(q, 1, "file io in progress\n"); 869 return -EBUSY; 870 } 871 return vb2_core_streamoff(q, type); 872 } 873 EXPORT_SYMBOL_GPL(vb2_streamoff); 874 875 int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) 876 { 877 struct vb2_buffer *vb; 878 879 if (eb->index >= q->num_buffers) { 880 dprintk(q, 1, "buffer index out of range\n"); 881 return -EINVAL; 882 } 883 vb = q->bufs[eb->index]; 884 885 return vb2_core_expbuf(q, &eb->fd, eb->type, vb, 886 eb->plane, eb->flags); 887 } 888 EXPORT_SYMBOL_GPL(vb2_expbuf); 889 890 int vb2_queue_init_name(struct vb2_queue *q, const char *name) 891 { 892 /* 893 * Sanity check 894 */ 895 if (WARN_ON(!q) || 896 WARN_ON(q->timestamp_flags & 897 ~(V4L2_BUF_FLAG_TIMESTAMP_MASK | 898 V4L2_BUF_FLAG_TSTAMP_SRC_MASK))) 899 return -EINVAL; 900 901 /* Warn that the driver should choose an appropriate timestamp type */ 902 WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == 903 V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN); 904 905 /* Warn that vb2_memory should match with v4l2_memory */ 906 if (WARN_ON(VB2_MEMORY_MMAP != (int)V4L2_MEMORY_MMAP) 907 || WARN_ON(VB2_MEMORY_USERPTR != (int)V4L2_MEMORY_USERPTR) 908 || WARN_ON(VB2_MEMORY_DMABUF != (int)V4L2_MEMORY_DMABUF)) 909 return -EINVAL; 910 911 if (q->buf_struct_size == 0) 912 q->buf_struct_size = sizeof(struct vb2_v4l2_buffer); 913 914 q->buf_ops = &v4l2_buf_ops; 915 q->is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type); 916 q->is_output = V4L2_TYPE_IS_OUTPUT(q->type); 917 q->copy_timestamp = (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) 918 == V4L2_BUF_FLAG_TIMESTAMP_COPY; 919 /* 920 * For compatibility with vb1: if QBUF hasn't been called yet, then 921 * return EPOLLERR as well. This only affects capture queues, output 922 * queues will always initialize waiting_for_buffers to false. 923 */ 924 q->quirk_poll_must_check_waiting_for_buffers = true; 925 926 if (name) 927 strscpy(q->name, name, sizeof(q->name)); 928 else 929 q->name[0] = '\0'; 930 931 return vb2_core_queue_init(q); 932 } 933 EXPORT_SYMBOL_GPL(vb2_queue_init_name); 934 935 int vb2_queue_init(struct vb2_queue *q) 936 { 937 return vb2_queue_init_name(q, NULL); 938 } 939 EXPORT_SYMBOL_GPL(vb2_queue_init); 940 941 void vb2_queue_release(struct vb2_queue *q) 942 { 943 vb2_core_queue_release(q); 944 } 945 EXPORT_SYMBOL_GPL(vb2_queue_release); 946 947 int vb2_queue_change_type(struct vb2_queue *q, unsigned int type) 948 { 949 if (type == q->type) 950 return 0; 951 952 if (vb2_is_busy(q)) 953 return -EBUSY; 954 955 q->type = type; 956 957 return 0; 958 } 959 EXPORT_SYMBOL_GPL(vb2_queue_change_type); 960 961 __poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) 962 { 963 struct video_device *vfd = video_devdata(file); 964 __poll_t res; 965 966 res = vb2_core_poll(q, file, wait); 967 968 if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { 969 struct v4l2_fh *fh = file->private_data; 970 971 poll_wait(file, &fh->wait, wait); 972 if (v4l2_event_pending(fh)) 973 res |= EPOLLPRI; 974 } 975 976 return res; 977 } 978 EXPORT_SYMBOL_GPL(vb2_poll); 979 980 /* 981 * The following functions are not part of the vb2 core API, but are helper 982 * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations 983 * and struct vb2_ops. 984 * They contain boilerplate code that most if not all drivers have to do 985 * and so they simplify the driver code. 986 */ 987 988 /* vb2 ioctl helpers */ 989 990 int vb2_ioctl_reqbufs(struct file *file, void *priv, 991 struct v4l2_requestbuffers *p) 992 { 993 struct video_device *vdev = video_devdata(file); 994 int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); 995 u32 flags = p->flags; 996 997 fill_buf_caps(vdev->queue, &p->capabilities); 998 validate_memory_flags(vdev->queue, p->memory, &flags); 999 p->flags = flags; 1000 if (res) 1001 return res; 1002 if (vb2_queue_is_busy(vdev->queue, file)) 1003 return -EBUSY; 1004 res = vb2_core_reqbufs(vdev->queue, p->memory, p->flags, &p->count); 1005 /* If count == 0, then the owner has released all buffers and he 1006 is no longer owner of the queue. Otherwise we have a new owner. */ 1007 if (res == 0) 1008 vdev->queue->owner = p->count ? file->private_data : NULL; 1009 return res; 1010 } 1011 EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs); 1012 1013 int vb2_ioctl_create_bufs(struct file *file, void *priv, 1014 struct v4l2_create_buffers *p) 1015 { 1016 struct video_device *vdev = video_devdata(file); 1017 int res = vb2_verify_memory_type(vdev->queue, p->memory, 1018 p->format.type); 1019 1020 p->index = vdev->queue->num_buffers; 1021 fill_buf_caps(vdev->queue, &p->capabilities); 1022 validate_memory_flags(vdev->queue, p->memory, &p->flags); 1023 /* 1024 * If count == 0, then just check if memory and type are valid. 1025 * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0. 1026 */ 1027 if (p->count == 0) 1028 return res != -EBUSY ? res : 0; 1029 if (res) 1030 return res; 1031 if (vb2_queue_is_busy(vdev->queue, file)) 1032 return -EBUSY; 1033 1034 res = vb2_create_bufs(vdev->queue, p); 1035 if (res == 0) 1036 vdev->queue->owner = file->private_data; 1037 return res; 1038 } 1039 EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs); 1040 1041 int vb2_ioctl_prepare_buf(struct file *file, void *priv, 1042 struct v4l2_buffer *p) 1043 { 1044 struct video_device *vdev = video_devdata(file); 1045 1046 if (vb2_queue_is_busy(vdev->queue, file)) 1047 return -EBUSY; 1048 return vb2_prepare_buf(vdev->queue, vdev->v4l2_dev->mdev, p); 1049 } 1050 EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf); 1051 1052 int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p) 1053 { 1054 struct video_device *vdev = video_devdata(file); 1055 1056 /* No need to call vb2_queue_is_busy(), anyone can query buffers. */ 1057 return vb2_querybuf(vdev->queue, p); 1058 } 1059 EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf); 1060 1061 int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p) 1062 { 1063 struct video_device *vdev = video_devdata(file); 1064 1065 if (vb2_queue_is_busy(vdev->queue, file)) 1066 return -EBUSY; 1067 return vb2_qbuf(vdev->queue, vdev->v4l2_dev->mdev, p); 1068 } 1069 EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf); 1070 1071 int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p) 1072 { 1073 struct video_device *vdev = video_devdata(file); 1074 1075 if (vb2_queue_is_busy(vdev->queue, file)) 1076 return -EBUSY; 1077 return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK); 1078 } 1079 EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf); 1080 1081 int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i) 1082 { 1083 struct video_device *vdev = video_devdata(file); 1084 1085 if (vb2_queue_is_busy(vdev->queue, file)) 1086 return -EBUSY; 1087 return vb2_streamon(vdev->queue, i); 1088 } 1089 EXPORT_SYMBOL_GPL(vb2_ioctl_streamon); 1090 1091 int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) 1092 { 1093 struct video_device *vdev = video_devdata(file); 1094 1095 if (vb2_queue_is_busy(vdev->queue, file)) 1096 return -EBUSY; 1097 return vb2_streamoff(vdev->queue, i); 1098 } 1099 EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff); 1100 1101 int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p) 1102 { 1103 struct video_device *vdev = video_devdata(file); 1104 1105 if (vb2_queue_is_busy(vdev->queue, file)) 1106 return -EBUSY; 1107 return vb2_expbuf(vdev->queue, p); 1108 } 1109 EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf); 1110 1111 /* v4l2_file_operations helpers */ 1112 1113 int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma) 1114 { 1115 struct video_device *vdev = video_devdata(file); 1116 1117 return vb2_mmap(vdev->queue, vma); 1118 } 1119 EXPORT_SYMBOL_GPL(vb2_fop_mmap); 1120 1121 int _vb2_fop_release(struct file *file, struct mutex *lock) 1122 { 1123 struct video_device *vdev = video_devdata(file); 1124 1125 if (lock) 1126 mutex_lock(lock); 1127 if (file->private_data == vdev->queue->owner) { 1128 vb2_queue_release(vdev->queue); 1129 vdev->queue->owner = NULL; 1130 } 1131 if (lock) 1132 mutex_unlock(lock); 1133 return v4l2_fh_release(file); 1134 } 1135 EXPORT_SYMBOL_GPL(_vb2_fop_release); 1136 1137 int vb2_fop_release(struct file *file) 1138 { 1139 struct video_device *vdev = video_devdata(file); 1140 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; 1141 1142 return _vb2_fop_release(file, lock); 1143 } 1144 EXPORT_SYMBOL_GPL(vb2_fop_release); 1145 1146 ssize_t vb2_fop_write(struct file *file, const char __user *buf, 1147 size_t count, loff_t *ppos) 1148 { 1149 struct video_device *vdev = video_devdata(file); 1150 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; 1151 int err = -EBUSY; 1152 1153 if (!(vdev->queue->io_modes & VB2_WRITE)) 1154 return -EINVAL; 1155 if (lock && mutex_lock_interruptible(lock)) 1156 return -ERESTARTSYS; 1157 if (vb2_queue_is_busy(vdev->queue, file)) 1158 goto exit; 1159 err = vb2_write(vdev->queue, buf, count, ppos, 1160 file->f_flags & O_NONBLOCK); 1161 if (vdev->queue->fileio) 1162 vdev->queue->owner = file->private_data; 1163 exit: 1164 if (lock) 1165 mutex_unlock(lock); 1166 return err; 1167 } 1168 EXPORT_SYMBOL_GPL(vb2_fop_write); 1169 1170 ssize_t vb2_fop_read(struct file *file, char __user *buf, 1171 size_t count, loff_t *ppos) 1172 { 1173 struct video_device *vdev = video_devdata(file); 1174 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; 1175 int err = -EBUSY; 1176 1177 if (!(vdev->queue->io_modes & VB2_READ)) 1178 return -EINVAL; 1179 if (lock && mutex_lock_interruptible(lock)) 1180 return -ERESTARTSYS; 1181 if (vb2_queue_is_busy(vdev->queue, file)) 1182 goto exit; 1183 vdev->queue->owner = file->private_data; 1184 err = vb2_read(vdev->queue, buf, count, ppos, 1185 file->f_flags & O_NONBLOCK); 1186 if (!vdev->queue->fileio) 1187 vdev->queue->owner = NULL; 1188 exit: 1189 if (lock) 1190 mutex_unlock(lock); 1191 return err; 1192 } 1193 EXPORT_SYMBOL_GPL(vb2_fop_read); 1194 1195 __poll_t vb2_fop_poll(struct file *file, poll_table *wait) 1196 { 1197 struct video_device *vdev = video_devdata(file); 1198 struct vb2_queue *q = vdev->queue; 1199 struct mutex *lock = q->lock ? q->lock : vdev->lock; 1200 __poll_t res; 1201 void *fileio; 1202 1203 /* 1204 * If this helper doesn't know how to lock, then you shouldn't be using 1205 * it but you should write your own. 1206 */ 1207 WARN_ON(!lock); 1208 1209 if (lock && mutex_lock_interruptible(lock)) 1210 return EPOLLERR; 1211 1212 fileio = q->fileio; 1213 1214 res = vb2_poll(vdev->queue, file, wait); 1215 1216 /* If fileio was started, then we have a new queue owner. */ 1217 if (!fileio && q->fileio) 1218 q->owner = file->private_data; 1219 if (lock) 1220 mutex_unlock(lock); 1221 return res; 1222 } 1223 EXPORT_SYMBOL_GPL(vb2_fop_poll); 1224 1225 #ifndef CONFIG_MMU 1226 unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr, 1227 unsigned long len, unsigned long pgoff, unsigned long flags) 1228 { 1229 struct video_device *vdev = video_devdata(file); 1230 1231 return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags); 1232 } 1233 EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area); 1234 #endif 1235 1236 void vb2_video_unregister_device(struct video_device *vdev) 1237 { 1238 /* Check if vdev was ever registered at all */ 1239 if (!vdev || !video_is_registered(vdev)) 1240 return; 1241 1242 /* 1243 * Calling this function only makes sense if vdev->queue is set. 1244 * If it is NULL, then just call video_unregister_device() instead. 1245 */ 1246 WARN_ON(!vdev->queue); 1247 1248 /* 1249 * Take a reference to the device since video_unregister_device() 1250 * calls device_unregister(), but we don't want that to release 1251 * the device since we want to clean up the queue first. 1252 */ 1253 get_device(&vdev->dev); 1254 video_unregister_device(vdev); 1255 if (vdev->queue && vdev->queue->owner) { 1256 struct mutex *lock = vdev->queue->lock ? 1257 vdev->queue->lock : vdev->lock; 1258 1259 if (lock) 1260 mutex_lock(lock); 1261 vb2_queue_release(vdev->queue); 1262 vdev->queue->owner = NULL; 1263 if (lock) 1264 mutex_unlock(lock); 1265 } 1266 /* 1267 * Now we put the device, and in most cases this will release 1268 * everything. 1269 */ 1270 put_device(&vdev->dev); 1271 } 1272 EXPORT_SYMBOL_GPL(vb2_video_unregister_device); 1273 1274 /* vb2_ops helpers. Only use if vq->lock is non-NULL. */ 1275 1276 void vb2_ops_wait_prepare(struct vb2_queue *vq) 1277 { 1278 mutex_unlock(vq->lock); 1279 } 1280 EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare); 1281 1282 void vb2_ops_wait_finish(struct vb2_queue *vq) 1283 { 1284 mutex_lock(vq->lock); 1285 } 1286 EXPORT_SYMBOL_GPL(vb2_ops_wait_finish); 1287 1288 /* 1289 * Note that this function is called during validation time and 1290 * thus the req_queue_mutex is held to ensure no request objects 1291 * can be added or deleted while validating. So there is no need 1292 * to protect the objects list. 1293 */ 1294 int vb2_request_validate(struct media_request *req) 1295 { 1296 struct media_request_object *obj; 1297 int ret = 0; 1298 1299 if (!vb2_request_buffer_cnt(req)) 1300 return -ENOENT; 1301 1302 list_for_each_entry(obj, &req->objects, list) { 1303 if (!obj->ops->prepare) 1304 continue; 1305 1306 ret = obj->ops->prepare(obj); 1307 if (ret) 1308 break; 1309 } 1310 1311 if (ret) { 1312 list_for_each_entry_continue_reverse(obj, &req->objects, list) 1313 if (obj->ops->unprepare) 1314 obj->ops->unprepare(obj); 1315 return ret; 1316 } 1317 return 0; 1318 } 1319 EXPORT_SYMBOL_GPL(vb2_request_validate); 1320 1321 void vb2_request_queue(struct media_request *req) 1322 { 1323 struct media_request_object *obj, *obj_safe; 1324 1325 /* 1326 * Queue all objects. Note that buffer objects are at the end of the 1327 * objects list, after all other object types. Once buffer objects 1328 * are queued, the driver might delete them immediately (if the driver 1329 * processes the buffer at once), so we have to use 1330 * list_for_each_entry_safe() to handle the case where the object we 1331 * queue is deleted. 1332 */ 1333 list_for_each_entry_safe(obj, obj_safe, &req->objects, list) 1334 if (obj->ops->queue) 1335 obj->ops->queue(obj); 1336 } 1337 EXPORT_SYMBOL_GPL(vb2_request_queue); 1338 1339 MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); 1340 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); 1341 MODULE_LICENSE("GPL"); 1342