2 * videobuf2-v4l2.c - V4L2 driver helper framework
4 * Copyright (C) 2010 Samsung Electronics
6 * Author: Pawel Osciak <pawel@osciak.com>
7 * Marek Szyprowski <m.szyprowski@samsung.com>
9 * The vb2_thread implementation was based on code from videobuf-dvb.c:
10 * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
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.
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>
23 #include <linux/module.h>
24 #include <linux/poll.h>
25 #include <linux/sched.h>
26 #include <linux/slab.h>
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>
34 #include <media/videobuf2-v4l2.h>
37 module_param(debug, int, 0644);
39 #define dprintk(q, level, fmt, arg...) \
42 pr_info("vb2-v4l2: [%p] %s: " fmt, \
43 (q)->name, __func__, ## arg); \
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)
61 * __verify_planes_array() - verify that the planes array passed in struct
62 * v4l2_buffer from userspace can be safely used
64 static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b)
66 if (!V4L2_TYPE_IS_MULTIPLANAR(b->type))
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");
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);
86 static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb)
88 return __verify_planes_array(vb, pb);
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.
95 static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b)
98 unsigned int bytesused;
101 if (V4L2_TYPE_IS_CAPTURE(b->type))
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;
113 if (b->m.planes[plane].bytesused > length)
116 if (b->m.planes[plane].data_offset > 0 &&
117 b->m.planes[plane].data_offset >= bytesused)
121 length = (b->memory == VB2_MEMORY_USERPTR)
122 ? b->length : vb->planes[0].length;
124 if (b->bytesused > length)
132 * __init_vb2_v4l2_buffer() - initialize the vb2_v4l2_buffer struct
134 static void __init_vb2_v4l2_buffer(struct vb2_buffer *vb)
136 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
138 vbuf->request_fd = -1;
141 static void __copy_timestamp(struct vb2_buffer *vb, const void *pb)
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;
149 * For output buffers copy the timestamp if needed,
150 * and the timecode field and flag if needed.
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;
160 static void vb2_warn_zero_bytesused(struct vb2_buffer *vb)
162 static bool check_once;
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");
173 pr_warn("use the actual size instead.\n");
176 static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
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;
184 ret = __verify_length(vb, b);
186 dprintk(q, 1, "plane parameters verification failed: %d\n", ret);
189 if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) {
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.
199 dprintk(q, 1, "the field is incorrectly set to ALTERNATE for an output buffer\n");
203 vbuf->request_fd = -1;
204 vbuf->is_held = false;
206 if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
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;
216 case VB2_MEMORY_DMABUF:
217 for (plane = 0; plane < vb->num_planes; ++plane) {
219 b->m.planes[plane].m.fd;
220 planes[plane].length =
221 b->m.planes[plane].length;
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;
234 /* Fill in driver-provided information for OUTPUT types */
235 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
237 * Will have to go up to b->length when API starts
238 * accepting variable number of planes.
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.
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.
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];
256 if (psrc->bytesused == 0)
257 vb2_warn_zero_bytesused(vb);
259 if (vb->vb2_queue->allow_zero_bytesused)
260 pdst->bytesused = psrc->bytesused;
262 pdst->bytesused = psrc->bytesused ?
263 psrc->bytesused : pdst->length;
264 pdst->data_offset = psrc->data_offset;
269 * Single-planar buffers do not use planes array,
270 * so fill in relevant v4l2_buffer struct fields instead.
271 * In videobuf we use our internal V4l2_planes struct for
272 * single-planar buffers as well, for simplicity.
274 * If bytesused == 0 for the output buffer, then fall back
275 * to the full buffer size as that's a sensible default.
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.
283 case VB2_MEMORY_USERPTR:
284 planes[0].m.userptr = b->m.userptr;
285 planes[0].length = b->length;
287 case VB2_MEMORY_DMABUF:
288 planes[0].m.fd = b->m.fd;
289 planes[0].length = b->length;
292 planes[0].m.offset = vb->planes[0].m.offset;
293 planes[0].length = vb->planes[0].length;
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);
302 if (vb->vb2_queue->allow_zero_bytesused)
303 planes[0].bytesused = b->bytesused;
305 planes[0].bytesused = b->bytesused ?
306 b->bytesused : planes[0].length;
308 planes[0].bytesused = 0;
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)) {
316 * Non-COPY timestamps and non-OUTPUT queues will get
317 * their timestamp and timestamp source flags from the
320 vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
323 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
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.
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;
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;
344 static void set_buffer_cache_hints(struct vb2_queue *q,
345 struct vb2_buffer *vb,
346 struct v4l2_buffer *b)
349 * DMA exporter should take care of cache syncs, so we can avoid
350 * explicit ->prepare()/->finish() syncs. For other ->memory types
351 * we always need ->prepare() or/and ->finish() cache sync.
353 if (q->memory == VB2_MEMORY_DMABUF) {
354 vb->need_cache_sync_on_finish = 0;
355 vb->need_cache_sync_on_prepare = 0;
360 * Cache sync/invalidation flags are set by default in order to
361 * preserve existing behaviour for old apps/drivers.
363 vb->need_cache_sync_on_prepare = 1;
364 vb->need_cache_sync_on_finish = 1;
366 if (!vb2_queue_allows_cache_hints(q)) {
368 * Clear buffer cache flags if queue does not support user
369 * space hints. That's to indicate to userspace that these
372 b->flags &= ~V4L2_BUF_FLAG_NO_CACHE_INVALIDATE;
373 b->flags &= ~V4L2_BUF_FLAG_NO_CACHE_CLEAN;
378 * ->finish() cache sync can be avoided when queue direction is
381 if (q->dma_dir == DMA_TO_DEVICE)
382 vb->need_cache_sync_on_finish = 0;
384 if (b->flags & V4L2_BUF_FLAG_NO_CACHE_INVALIDATE)
385 vb->need_cache_sync_on_finish = 0;
387 if (b->flags & V4L2_BUF_FLAG_NO_CACHE_CLEAN)
388 vb->need_cache_sync_on_prepare = 0;
391 static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
392 struct v4l2_buffer *b, bool is_prepare,
393 struct media_request **p_req)
395 const char *opname = is_prepare ? "prepare_buf" : "qbuf";
396 struct media_request *req;
397 struct vb2_v4l2_buffer *vbuf;
398 struct vb2_buffer *vb;
401 if (b->type != q->type) {
402 dprintk(q, 1, "%s: invalid buffer type\n", opname);
406 if (b->index >= q->num_buffers) {
407 dprintk(q, 1, "%s: buffer index out of range\n", opname);
411 if (q->bufs[b->index] == NULL) {
412 /* Should never happen */
413 dprintk(q, 1, "%s: buffer is NULL\n", opname);
417 if (b->memory != q->memory) {
418 dprintk(q, 1, "%s: invalid memory type\n", opname);
422 vb = q->bufs[b->index];
423 vbuf = to_vb2_v4l2_buffer(vb);
424 ret = __verify_planes_array(vb, b);
428 if (!is_prepare && (b->flags & V4L2_BUF_FLAG_REQUEST_FD) &&
429 vb->state != VB2_BUF_STATE_DEQUEUED) {
430 dprintk(q, 1, "%s: buffer is not in dequeued state\n", opname);
435 set_buffer_cache_hints(q, vb, b);
436 /* Copy relevant information provided by the userspace */
437 memset(vbuf->planes, 0,
438 sizeof(vbuf->planes[0]) * vb->num_planes);
439 ret = vb2_fill_vb2_v4l2_buffer(vb, b);
447 if (!(b->flags & V4L2_BUF_FLAG_REQUEST_FD)) {
448 if (q->requires_requests) {
449 dprintk(q, 1, "%s: queue requires requests\n", opname);
452 if (q->uses_requests) {
453 dprintk(q, 1, "%s: queue uses requests\n", opname);
457 } else if (!q->supports_requests) {
458 dprintk(q, 1, "%s: queue does not support requests\n", opname);
460 } else if (q->uses_qbuf) {
461 dprintk(q, 1, "%s: queue does not use requests\n", opname);
466 * For proper locking when queueing a request you need to be able
467 * to lock access to the vb2 queue, so check that there is a lock
468 * that we can use. In addition p_req must be non-NULL.
470 if (WARN_ON(!q->lock || !p_req))
474 * Make sure this op is implemented by the driver. It's easy to forget
475 * this callback, but is it important when canceling a buffer in a
478 if (WARN_ON(!q->ops->buf_request_complete))
481 * Make sure this op is implemented by the driver for the output queue.
482 * It's easy to forget this callback, but is it important to correctly
483 * validate the 'field' value at QBUF time.
485 if (WARN_ON((q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT ||
486 q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) &&
487 !q->ops->buf_out_validate))
490 if (b->request_fd < 0) {
491 dprintk(q, 1, "%s: request_fd < 0\n", opname);
495 req = media_request_get_by_fd(mdev, b->request_fd);
497 dprintk(q, 1, "%s: invalid request_fd\n", opname);
502 * Early sanity check. This is checked again when the buffer
503 * is bound to the request in vb2_core_qbuf().
505 if (req->state != MEDIA_REQUEST_STATE_IDLE &&
506 req->state != MEDIA_REQUEST_STATE_UPDATING) {
507 dprintk(q, 1, "%s: request is not idle\n", opname);
508 media_request_put(req);
513 vbuf->request_fd = b->request_fd;
519 * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be
520 * returned to userspace
522 static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb)
524 struct v4l2_buffer *b = pb;
525 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
526 struct vb2_queue *q = vb->vb2_queue;
529 /* Copy back data such as timestamp, flags, etc. */
530 b->index = vb->index;
532 b->memory = vb->memory;
535 b->flags = vbuf->flags;
536 b->field = vbuf->field;
537 v4l2_buffer_set_timestamp(b, vb->timestamp);
538 b->timecode = vbuf->timecode;
539 b->sequence = vbuf->sequence;
543 if (q->is_multiplanar) {
545 * Fill in plane-related data if userspace provided an array
546 * for it. The caller has already verified memory and size.
548 b->length = vb->num_planes;
549 for (plane = 0; plane < vb->num_planes; ++plane) {
550 struct v4l2_plane *pdst = &b->m.planes[plane];
551 struct vb2_plane *psrc = &vb->planes[plane];
553 pdst->bytesused = psrc->bytesused;
554 pdst->length = psrc->length;
555 if (q->memory == VB2_MEMORY_MMAP)
556 pdst->m.mem_offset = psrc->m.offset;
557 else if (q->memory == VB2_MEMORY_USERPTR)
558 pdst->m.userptr = psrc->m.userptr;
559 else if (q->memory == VB2_MEMORY_DMABUF)
560 pdst->m.fd = psrc->m.fd;
561 pdst->data_offset = psrc->data_offset;
562 memset(pdst->reserved, 0, sizeof(pdst->reserved));
566 * We use length and offset in v4l2_planes array even for
567 * single-planar buffers, but userspace does not.
569 b->length = vb->planes[0].length;
570 b->bytesused = vb->planes[0].bytesused;
571 if (q->memory == VB2_MEMORY_MMAP)
572 b->m.offset = vb->planes[0].m.offset;
573 else if (q->memory == VB2_MEMORY_USERPTR)
574 b->m.userptr = vb->planes[0].m.userptr;
575 else if (q->memory == VB2_MEMORY_DMABUF)
576 b->m.fd = vb->planes[0].m.fd;
580 * Clear any buffer state related flags.
582 b->flags &= ~V4L2_BUFFER_MASK_FLAGS;
583 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK;
584 if (!q->copy_timestamp) {
586 * For non-COPY timestamps, drop timestamp source bits
587 * and obtain the timestamp source from the queue.
589 b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
590 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
594 case VB2_BUF_STATE_QUEUED:
595 case VB2_BUF_STATE_ACTIVE:
596 b->flags |= V4L2_BUF_FLAG_QUEUED;
598 case VB2_BUF_STATE_IN_REQUEST:
599 b->flags |= V4L2_BUF_FLAG_IN_REQUEST;
601 case VB2_BUF_STATE_ERROR:
602 b->flags |= V4L2_BUF_FLAG_ERROR;
604 case VB2_BUF_STATE_DONE:
605 b->flags |= V4L2_BUF_FLAG_DONE;
607 case VB2_BUF_STATE_PREPARING:
608 case VB2_BUF_STATE_DEQUEUED:
613 if ((vb->state == VB2_BUF_STATE_DEQUEUED ||
614 vb->state == VB2_BUF_STATE_IN_REQUEST) &&
615 vb->synced && vb->prepared)
616 b->flags |= V4L2_BUF_FLAG_PREPARED;
618 if (vb2_buffer_in_use(q, vb))
619 b->flags |= V4L2_BUF_FLAG_MAPPED;
620 if (vbuf->request_fd >= 0) {
621 b->flags |= V4L2_BUF_FLAG_REQUEST_FD;
622 b->request_fd = vbuf->request_fd;
627 * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a
628 * v4l2_buffer by the userspace. It also verifies that struct
629 * v4l2_buffer has a valid number of planes.
631 static int __fill_vb2_buffer(struct vb2_buffer *vb, struct vb2_plane *planes)
633 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
636 if (!vb->vb2_queue->copy_timestamp)
639 for (plane = 0; plane < vb->num_planes; ++plane) {
640 if (vb->vb2_queue->memory != VB2_MEMORY_MMAP) {
641 planes[plane].m = vbuf->planes[plane].m;
642 planes[plane].length = vbuf->planes[plane].length;
644 planes[plane].bytesused = vbuf->planes[plane].bytesused;
645 planes[plane].data_offset = vbuf->planes[plane].data_offset;
650 static const struct vb2_buf_ops v4l2_buf_ops = {
651 .verify_planes_array = __verify_planes_array_core,
652 .init_buffer = __init_vb2_v4l2_buffer,
653 .fill_user_buffer = __fill_v4l2_buffer,
654 .fill_vb2_buffer = __fill_vb2_buffer,
655 .copy_timestamp = __copy_timestamp,
658 int vb2_find_timestamp(const struct vb2_queue *q, u64 timestamp,
659 unsigned int start_idx)
663 for (i = start_idx; i < q->num_buffers; i++)
664 if (q->bufs[i]->copied_timestamp &&
665 q->bufs[i]->timestamp == timestamp)
669 EXPORT_SYMBOL_GPL(vb2_find_timestamp);
672 * vb2_querybuf() - query video buffer information
674 * @b: buffer struct passed from userspace to vidioc_querybuf handler
677 * Should be called from vidioc_querybuf ioctl handler in driver.
678 * This function will verify the passed v4l2_buffer structure and fill the
679 * relevant information for the userspace.
681 * The return values from this function are intended to be directly returned
682 * from vidioc_querybuf handler in driver.
684 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
686 struct vb2_buffer *vb;
689 if (b->type != q->type) {
690 dprintk(q, 1, "wrong buffer type\n");
694 if (b->index >= q->num_buffers) {
695 dprintk(q, 1, "buffer index out of range\n");
698 vb = q->bufs[b->index];
699 ret = __verify_planes_array(vb, b);
701 vb2_core_querybuf(q, b->index, b);
704 EXPORT_SYMBOL(vb2_querybuf);
706 static void fill_buf_caps(struct vb2_queue *q, u32 *caps)
708 *caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS;
709 if (q->io_modes & VB2_MMAP)
710 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP;
711 if (q->io_modes & VB2_USERPTR)
712 *caps |= V4L2_BUF_CAP_SUPPORTS_USERPTR;
713 if (q->io_modes & VB2_DMABUF)
714 *caps |= V4L2_BUF_CAP_SUPPORTS_DMABUF;
715 if (q->subsystem_flags & VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF)
716 *caps |= V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF;
717 if (q->allow_cache_hints && q->io_modes & VB2_MMAP)
718 *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS;
719 #ifdef CONFIG_MEDIA_CONTROLLER_REQUEST_API
720 if (q->supports_requests)
721 *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS;
725 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
727 int ret = vb2_verify_memory_type(q, req->memory, req->type);
729 fill_buf_caps(q, &req->capabilities);
730 return ret ? ret : vb2_core_reqbufs(q, req->memory, &req->count);
732 EXPORT_SYMBOL_GPL(vb2_reqbufs);
734 int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
735 struct v4l2_buffer *b)
739 if (vb2_fileio_is_active(q)) {
740 dprintk(q, 1, "file io in progress\n");
744 if (b->flags & V4L2_BUF_FLAG_REQUEST_FD)
747 ret = vb2_queue_or_prepare_buf(q, mdev, b, true, NULL);
749 return ret ? ret : vb2_core_prepare_buf(q, b->index, b);
751 EXPORT_SYMBOL_GPL(vb2_prepare_buf);
753 int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
755 unsigned requested_planes = 1;
756 unsigned requested_sizes[VIDEO_MAX_PLANES];
757 struct v4l2_format *f = &create->format;
758 int ret = vb2_verify_memory_type(q, create->memory, f->type);
761 fill_buf_caps(q, &create->capabilities);
762 create->index = q->num_buffers;
763 if (create->count == 0)
764 return ret != -EBUSY ? ret : 0;
767 case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
768 case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
769 requested_planes = f->fmt.pix_mp.num_planes;
770 if (requested_planes == 0 ||
771 requested_planes > VIDEO_MAX_PLANES)
773 for (i = 0; i < requested_planes; i++)
775 f->fmt.pix_mp.plane_fmt[i].sizeimage;
777 case V4L2_BUF_TYPE_VIDEO_CAPTURE:
778 case V4L2_BUF_TYPE_VIDEO_OUTPUT:
779 requested_sizes[0] = f->fmt.pix.sizeimage;
781 case V4L2_BUF_TYPE_VBI_CAPTURE:
782 case V4L2_BUF_TYPE_VBI_OUTPUT:
783 requested_sizes[0] = f->fmt.vbi.samples_per_line *
784 (f->fmt.vbi.count[0] + f->fmt.vbi.count[1]);
786 case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE:
787 case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT:
788 requested_sizes[0] = f->fmt.sliced.io_size;
790 case V4L2_BUF_TYPE_SDR_CAPTURE:
791 case V4L2_BUF_TYPE_SDR_OUTPUT:
792 requested_sizes[0] = f->fmt.sdr.buffersize;
794 case V4L2_BUF_TYPE_META_CAPTURE:
795 case V4L2_BUF_TYPE_META_OUTPUT:
796 requested_sizes[0] = f->fmt.meta.buffersize;
801 for (i = 0; i < requested_planes; i++)
802 if (requested_sizes[i] == 0)
804 return ret ? ret : vb2_core_create_bufs(q, create->memory,
809 EXPORT_SYMBOL_GPL(vb2_create_bufs);
811 int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev,
812 struct v4l2_buffer *b)
814 struct media_request *req = NULL;
817 if (vb2_fileio_is_active(q)) {
818 dprintk(q, 1, "file io in progress\n");
822 ret = vb2_queue_or_prepare_buf(q, mdev, b, false, &req);
825 ret = vb2_core_qbuf(q, b->index, b, req);
827 media_request_put(req);
830 EXPORT_SYMBOL_GPL(vb2_qbuf);
832 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
836 if (vb2_fileio_is_active(q)) {
837 dprintk(q, 1, "file io in progress\n");
841 if (b->type != q->type) {
842 dprintk(q, 1, "invalid buffer type\n");
846 ret = vb2_core_dqbuf(q, NULL, b, nonblocking);
849 b->flags & V4L2_BUF_FLAG_DONE &&
850 b->flags & V4L2_BUF_FLAG_LAST)
851 q->last_buffer_dequeued = true;
854 * After calling the VIDIOC_DQBUF V4L2_BUF_FLAG_DONE must be
857 b->flags &= ~V4L2_BUF_FLAG_DONE;
861 EXPORT_SYMBOL_GPL(vb2_dqbuf);
863 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
865 if (vb2_fileio_is_active(q)) {
866 dprintk(q, 1, "file io in progress\n");
869 return vb2_core_streamon(q, type);
871 EXPORT_SYMBOL_GPL(vb2_streamon);
873 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type)
875 if (vb2_fileio_is_active(q)) {
876 dprintk(q, 1, "file io in progress\n");
879 return vb2_core_streamoff(q, type);
881 EXPORT_SYMBOL_GPL(vb2_streamoff);
883 int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
885 return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index,
886 eb->plane, eb->flags);
888 EXPORT_SYMBOL_GPL(vb2_expbuf);
890 int vb2_queue_init_name(struct vb2_queue *q, const char *name)
896 WARN_ON(q->timestamp_flags &
897 ~(V4L2_BUF_FLAG_TIMESTAMP_MASK |
898 V4L2_BUF_FLAG_TSTAMP_SRC_MASK)))
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);
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))
911 if (q->buf_struct_size == 0)
912 q->buf_struct_size = sizeof(struct vb2_v4l2_buffer);
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;
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.
924 q->quirk_poll_must_check_waiting_for_buffers = true;
927 strscpy(q->name, name, sizeof(q->name));
931 return vb2_core_queue_init(q);
933 EXPORT_SYMBOL_GPL(vb2_queue_init_name);
935 int vb2_queue_init(struct vb2_queue *q)
937 return vb2_queue_init_name(q, NULL);
939 EXPORT_SYMBOL_GPL(vb2_queue_init);
941 void vb2_queue_release(struct vb2_queue *q)
943 vb2_core_queue_release(q);
945 EXPORT_SYMBOL_GPL(vb2_queue_release);
947 __poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
949 struct video_device *vfd = video_devdata(file);
952 res = vb2_core_poll(q, file, wait);
954 if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
955 struct v4l2_fh *fh = file->private_data;
957 poll_wait(file, &fh->wait, wait);
958 if (v4l2_event_pending(fh))
964 EXPORT_SYMBOL_GPL(vb2_poll);
967 * The following functions are not part of the vb2 core API, but are helper
968 * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations
969 * and struct vb2_ops.
970 * They contain boilerplate code that most if not all drivers have to do
971 * and so they simplify the driver code.
974 /* The queue is busy if there is a owner and you are not that owner. */
975 static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file)
977 return vdev->queue->owner && vdev->queue->owner != file->private_data;
980 /* vb2 ioctl helpers */
982 int vb2_ioctl_reqbufs(struct file *file, void *priv,
983 struct v4l2_requestbuffers *p)
985 struct video_device *vdev = video_devdata(file);
986 int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type);
988 fill_buf_caps(vdev->queue, &p->capabilities);
991 if (vb2_queue_is_busy(vdev, file))
993 res = vb2_core_reqbufs(vdev->queue, p->memory, &p->count);
994 /* If count == 0, then the owner has released all buffers and he
995 is no longer owner of the queue. Otherwise we have a new owner. */
997 vdev->queue->owner = p->count ? file->private_data : NULL;
1000 EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs);
1002 int vb2_ioctl_create_bufs(struct file *file, void *priv,
1003 struct v4l2_create_buffers *p)
1005 struct video_device *vdev = video_devdata(file);
1006 int res = vb2_verify_memory_type(vdev->queue, p->memory,
1009 p->index = vdev->queue->num_buffers;
1010 fill_buf_caps(vdev->queue, &p->capabilities);
1012 * If count == 0, then just check if memory and type are valid.
1013 * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0.
1016 return res != -EBUSY ? res : 0;
1019 if (vb2_queue_is_busy(vdev, file))
1022 res = vb2_create_bufs(vdev->queue, p);
1024 vdev->queue->owner = file->private_data;
1027 EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs);
1029 int vb2_ioctl_prepare_buf(struct file *file, void *priv,
1030 struct v4l2_buffer *p)
1032 struct video_device *vdev = video_devdata(file);
1034 if (vb2_queue_is_busy(vdev, file))
1036 return vb2_prepare_buf(vdev->queue, vdev->v4l2_dev->mdev, p);
1038 EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf);
1040 int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p)
1042 struct video_device *vdev = video_devdata(file);
1044 /* No need to call vb2_queue_is_busy(), anyone can query buffers. */
1045 return vb2_querybuf(vdev->queue, p);
1047 EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf);
1049 int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p)
1051 struct video_device *vdev = video_devdata(file);
1053 if (vb2_queue_is_busy(vdev, file))
1055 return vb2_qbuf(vdev->queue, vdev->v4l2_dev->mdev, p);
1057 EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf);
1059 int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p)
1061 struct video_device *vdev = video_devdata(file);
1063 if (vb2_queue_is_busy(vdev, file))
1065 return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK);
1067 EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf);
1069 int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
1071 struct video_device *vdev = video_devdata(file);
1073 if (vb2_queue_is_busy(vdev, file))
1075 return vb2_streamon(vdev->queue, i);
1077 EXPORT_SYMBOL_GPL(vb2_ioctl_streamon);
1079 int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
1081 struct video_device *vdev = video_devdata(file);
1083 if (vb2_queue_is_busy(vdev, file))
1085 return vb2_streamoff(vdev->queue, i);
1087 EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff);
1089 int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p)
1091 struct video_device *vdev = video_devdata(file);
1093 if (vb2_queue_is_busy(vdev, file))
1095 return vb2_expbuf(vdev->queue, p);
1097 EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf);
1099 /* v4l2_file_operations helpers */
1101 int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma)
1103 struct video_device *vdev = video_devdata(file);
1105 return vb2_mmap(vdev->queue, vma);
1107 EXPORT_SYMBOL_GPL(vb2_fop_mmap);
1109 int _vb2_fop_release(struct file *file, struct mutex *lock)
1111 struct video_device *vdev = video_devdata(file);
1115 if (file->private_data == vdev->queue->owner) {
1116 vb2_queue_release(vdev->queue);
1117 vdev->queue->owner = NULL;
1121 return v4l2_fh_release(file);
1123 EXPORT_SYMBOL_GPL(_vb2_fop_release);
1125 int vb2_fop_release(struct file *file)
1127 struct video_device *vdev = video_devdata(file);
1128 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
1130 return _vb2_fop_release(file, lock);
1132 EXPORT_SYMBOL_GPL(vb2_fop_release);
1134 ssize_t vb2_fop_write(struct file *file, const char __user *buf,
1135 size_t count, loff_t *ppos)
1137 struct video_device *vdev = video_devdata(file);
1138 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
1141 if (!(vdev->queue->io_modes & VB2_WRITE))
1143 if (lock && mutex_lock_interruptible(lock))
1144 return -ERESTARTSYS;
1145 if (vb2_queue_is_busy(vdev, file))
1147 err = vb2_write(vdev->queue, buf, count, ppos,
1148 file->f_flags & O_NONBLOCK);
1149 if (vdev->queue->fileio)
1150 vdev->queue->owner = file->private_data;
1156 EXPORT_SYMBOL_GPL(vb2_fop_write);
1158 ssize_t vb2_fop_read(struct file *file, char __user *buf,
1159 size_t count, loff_t *ppos)
1161 struct video_device *vdev = video_devdata(file);
1162 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
1165 if (!(vdev->queue->io_modes & VB2_READ))
1167 if (lock && mutex_lock_interruptible(lock))
1168 return -ERESTARTSYS;
1169 if (vb2_queue_is_busy(vdev, file))
1171 err = vb2_read(vdev->queue, buf, count, ppos,
1172 file->f_flags & O_NONBLOCK);
1173 if (vdev->queue->fileio)
1174 vdev->queue->owner = file->private_data;
1180 EXPORT_SYMBOL_GPL(vb2_fop_read);
1182 __poll_t vb2_fop_poll(struct file *file, poll_table *wait)
1184 struct video_device *vdev = video_devdata(file);
1185 struct vb2_queue *q = vdev->queue;
1186 struct mutex *lock = q->lock ? q->lock : vdev->lock;
1191 * If this helper doesn't know how to lock, then you shouldn't be using
1192 * it but you should write your own.
1196 if (lock && mutex_lock_interruptible(lock))
1201 res = vb2_poll(vdev->queue, file, wait);
1203 /* If fileio was started, then we have a new queue owner. */
1204 if (!fileio && q->fileio)
1205 q->owner = file->private_data;
1210 EXPORT_SYMBOL_GPL(vb2_fop_poll);
1213 unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
1214 unsigned long len, unsigned long pgoff, unsigned long flags)
1216 struct video_device *vdev = video_devdata(file);
1218 return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags);
1220 EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area);
1223 void vb2_video_unregister_device(struct video_device *vdev)
1225 /* Check if vdev was ever registered at all */
1226 if (!vdev || !video_is_registered(vdev))
1230 * Calling this function only makes sense if vdev->queue is set.
1231 * If it is NULL, then just call video_unregister_device() instead.
1233 WARN_ON(!vdev->queue);
1236 * Take a reference to the device since video_unregister_device()
1237 * calls device_unregister(), but we don't want that to release
1238 * the device since we want to clean up the queue first.
1240 get_device(&vdev->dev);
1241 video_unregister_device(vdev);
1242 if (vdev->queue && vdev->queue->owner) {
1243 struct mutex *lock = vdev->queue->lock ?
1244 vdev->queue->lock : vdev->lock;
1248 vb2_queue_release(vdev->queue);
1249 vdev->queue->owner = NULL;
1254 * Now we put the device, and in most cases this will release
1257 put_device(&vdev->dev);
1259 EXPORT_SYMBOL_GPL(vb2_video_unregister_device);
1261 /* vb2_ops helpers. Only use if vq->lock is non-NULL. */
1263 void vb2_ops_wait_prepare(struct vb2_queue *vq)
1265 mutex_unlock(vq->lock);
1267 EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare);
1269 void vb2_ops_wait_finish(struct vb2_queue *vq)
1271 mutex_lock(vq->lock);
1273 EXPORT_SYMBOL_GPL(vb2_ops_wait_finish);
1276 * Note that this function is called during validation time and
1277 * thus the req_queue_mutex is held to ensure no request objects
1278 * can be added or deleted while validating. So there is no need
1279 * to protect the objects list.
1281 int vb2_request_validate(struct media_request *req)
1283 struct media_request_object *obj;
1286 if (!vb2_request_buffer_cnt(req))
1289 list_for_each_entry(obj, &req->objects, list) {
1290 if (!obj->ops->prepare)
1293 ret = obj->ops->prepare(obj);
1299 list_for_each_entry_continue_reverse(obj, &req->objects, list)
1300 if (obj->ops->unprepare)
1301 obj->ops->unprepare(obj);
1306 EXPORT_SYMBOL_GPL(vb2_request_validate);
1308 void vb2_request_queue(struct media_request *req)
1310 struct media_request_object *obj, *obj_safe;
1313 * Queue all objects. Note that buffer objects are at the end of the
1314 * objects list, after all other object types. Once buffer objects
1315 * are queued, the driver might delete them immediately (if the driver
1316 * processes the buffer at once), so we have to use
1317 * list_for_each_entry_safe() to handle the case where the object we
1320 list_for_each_entry_safe(obj, obj_safe, &req->objects, list)
1321 if (obj->ops->queue)
1322 obj->ops->queue(obj);
1324 EXPORT_SYMBOL_GPL(vb2_request_queue);
1326 MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2");
1327 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski");
1328 MODULE_LICENSE("GPL");