diff options
Diffstat (limited to 'drivers/media/common/videobuf2/videobuf2-v4l2.c')
| -rw-r--r-- | drivers/media/common/videobuf2/videobuf2-v4l2.c | 966 |
1 files changed, 966 insertions, 0 deletions
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c new file mode 100644 index 000000000000..d9a487aab99c --- /dev/null +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -0,0 +1,966 @@ +/* + * videobuf2-v4l2.c - V4L2 driver helper framework + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Pawel Osciak <pawel@osciak.com> + * Marek Szyprowski <m.szyprowski@samsung.com> + * + * The vb2_thread implementation was based on code from videobuf-dvb.c: + * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs] + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/freezer.h> +#include <linux/kthread.h> + +#include <media/v4l2-dev.h> +#include <media/v4l2-fh.h> +#include <media/v4l2-event.h> +#include <media/v4l2-common.h> + +#include <media/videobuf2-v4l2.h> + +static int debug; +module_param(debug, int, 0644); + +#define dprintk(level, fmt, arg...) \ + do { \ + if (debug >= level) \ + pr_info("vb2-v4l2: %s: " fmt, __func__, ## arg); \ + } while (0) + +/* Flags that are set by the vb2 core */ +#define V4L2_BUFFER_MASK_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \ + V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \ + V4L2_BUF_FLAG_PREPARED | \ + V4L2_BUF_FLAG_TIMESTAMP_MASK) +/* Output buffer flags that should be passed on to the driver */ +#define V4L2_BUFFER_OUT_FLAGS (V4L2_BUF_FLAG_PFRAME | V4L2_BUF_FLAG_BFRAME | \ + V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_TIMECODE) + +/* + * __verify_planes_array() - verify that the planes array passed in struct + * v4l2_buffer from userspace can be safely used + */ +static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + if (!V4L2_TYPE_IS_MULTIPLANAR(b->type)) + return 0; + + /* Is memory for copying plane information present? */ + if (b->m.planes == NULL) { + dprintk(1, "multi-planar buffer passed but planes array not provided\n"); + return -EINVAL; + } + + if (b->length < vb->num_planes || b->length > VB2_MAX_PLANES) { + dprintk(1, "incorrect planes array length, expected %d, got %d\n", + vb->num_planes, b->length); + return -EINVAL; + } + + return 0; +} + +static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb) +{ + return __verify_planes_array(vb, pb); +} + +/* + * __verify_length() - Verify that the bytesused value for each plane fits in + * the plane length and that the data offset doesn't exceed the bytesused value. + */ +static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + unsigned int length; + unsigned int bytesused; + unsigned int plane; + + if (!V4L2_TYPE_IS_OUTPUT(b->type)) + return 0; + + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { + for (plane = 0; plane < vb->num_planes; ++plane) { + length = (b->memory == VB2_MEMORY_USERPTR || + b->memory == VB2_MEMORY_DMABUF) + ? b->m.planes[plane].length + : vb->planes[plane].length; + bytesused = b->m.planes[plane].bytesused + ? b->m.planes[plane].bytesused : length; + + if (b->m.planes[plane].bytesused > length) + return -EINVAL; + + if (b->m.planes[plane].data_offset > 0 && + b->m.planes[plane].data_offset >= bytesused) + return -EINVAL; + } + } else { + length = (b->memory == VB2_MEMORY_USERPTR) + ? b->length : vb->planes[0].length; + + if (b->bytesused > length) + return -EINVAL; + } + + return 0; +} + +static void __copy_timestamp(struct vb2_buffer *vb, const void *pb) +{ + const struct v4l2_buffer *b = pb; + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); + struct vb2_queue *q = vb->vb2_queue; + + if (q->is_output) { + /* + * For output buffers copy the timestamp if needed, + * and the timecode field and flag if needed. + */ + if (q->copy_timestamp) + vb->timestamp = timeval_to_ns(&b->timestamp); + vbuf->flags |= b->flags & V4L2_BUF_FLAG_TIMECODE; + if (b->flags & V4L2_BUF_FLAG_TIMECODE) + vbuf->timecode = b->timecode; + } +}; + +static void vb2_warn_zero_bytesused(struct vb2_buffer *vb) +{ + static bool check_once; + + if (check_once) + return; + + check_once = true; + WARN_ON(1); + + pr_warn("use of bytesused == 0 is deprecated and will be removed in the future,\n"); + if (vb->vb2_queue->allow_zero_bytesused) + pr_warn("use VIDIOC_DECODER_CMD(V4L2_DEC_CMD_STOP) instead.\n"); + else + pr_warn("use the actual size instead.\n"); +} + +static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b, + const char *opname) +{ + if (b->type != q->type) { + dprintk(1, "%s: invalid buffer type\n", opname); + return -EINVAL; + } + + if (b->index >= q->num_buffers) { + dprintk(1, "%s: buffer index out of range\n", opname); + return -EINVAL; + } + + if (q->bufs[b->index] == NULL) { + /* Should never happen */ + dprintk(1, "%s: buffer is NULL\n", opname); + return -EINVAL; + } + + if (b->memory != q->memory) { + dprintk(1, "%s: invalid memory type\n", opname); + return -EINVAL; + } + + return __verify_planes_array(q->bufs[b->index], b); +} + +/* + * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be + * returned to userspace + */ +static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb) +{ + struct v4l2_buffer *b = pb; + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); + struct vb2_queue *q = vb->vb2_queue; + unsigned int plane; + + /* Copy back data such as timestamp, flags, etc. */ + b->index = vb->index; + b->type = vb->type; + b->memory = vb->memory; + b->bytesused = 0; + + b->flags = vbuf->flags; + b->field = vbuf->field; + b->timestamp = ns_to_timeval(vb->timestamp); + b->timecode = vbuf->timecode; + b->sequence = vbuf->sequence; + b->reserved2 = 0; + b->reserved = 0; + + if (q->is_multiplanar) { + /* + * Fill in plane-related data if userspace provided an array + * for it. The caller has already verified memory and size. + */ + b->length = vb->num_planes; + for (plane = 0; plane < vb->num_planes; ++plane) { + struct v4l2_plane *pdst = &b->m.planes[plane]; + struct vb2_plane *psrc = &vb->planes[plane]; + + pdst->bytesused = psrc->bytesused; + pdst->length = psrc->length; + if (q->memory == VB2_MEMORY_MMAP) + pdst->m.mem_offset = psrc->m.offset; + else if (q->memory == VB2_MEMORY_USERPTR) + pdst->m.userptr = psrc->m.userptr; + else if (q->memory == VB2_MEMORY_DMABUF) + pdst->m.fd = psrc->m.fd; + pdst->data_offset = psrc->data_offset; + memset(pdst->reserved, 0, sizeof(pdst->reserved)); + } + } else { + /* + * We use length and offset in v4l2_planes array even for + * single-planar buffers, but userspace does not. + */ + b->length = vb->planes[0].length; + b->bytesused = vb->planes[0].bytesused; + if (q->memory == VB2_MEMORY_MMAP) + b->m.offset = vb->planes[0].m.offset; + else if (q->memory == VB2_MEMORY_USERPTR) + b->m.userptr = vb->planes[0].m.userptr; + else if (q->memory == VB2_MEMORY_DMABUF) + b->m.fd = vb->planes[0].m.fd; + } + + /* + * Clear any buffer state related flags. + */ + b->flags &= ~V4L2_BUFFER_MASK_FLAGS; + b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK; + if (!q->copy_timestamp) { + /* + * For non-COPY timestamps, drop timestamp source bits + * and obtain the timestamp source from the queue. + */ + b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + } + + switch (vb->state) { + case VB2_BUF_STATE_QUEUED: + case VB2_BUF_STATE_ACTIVE: + b->flags |= V4L2_BUF_FLAG_QUEUED; + break; + case VB2_BUF_STATE_ERROR: + b->flags |= V4L2_BUF_FLAG_ERROR; + /* fall through */ + case VB2_BUF_STATE_DONE: + b->flags |= V4L2_BUF_FLAG_DONE; + break; + case VB2_BUF_STATE_PREPARED: + b->flags |= V4L2_BUF_FLAG_PREPARED; + break; + case VB2_BUF_STATE_PREPARING: + case VB2_BUF_STATE_DEQUEUED: + case VB2_BUF_STATE_REQUEUEING: + /* nothing */ + break; + } + + if (vb2_buffer_in_use(q, vb)) + b->flags |= V4L2_BUF_FLAG_MAPPED; + + if (!q->is_output && + b->flags & V4L2_BUF_FLAG_DONE && + b->flags & V4L2_BUF_FLAG_LAST) + q->last_buffer_dequeued = true; +} + +/* + * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a + * v4l2_buffer by the userspace. It also verifies that struct + * v4l2_buffer has a valid number of planes. + */ +static int __fill_vb2_buffer(struct vb2_buffer *vb, + const void *pb, struct vb2_plane *planes) +{ + struct vb2_queue *q = vb->vb2_queue; + const struct v4l2_buffer *b = pb; + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); + unsigned int plane; + int ret; + + ret = __verify_length(vb, b); + if (ret < 0) { + dprintk(1, "plane parameters verification failed: %d\n", ret); + return ret; + } + if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) { + /* + * If the format's field is ALTERNATE, then the buffer's field + * should be either TOP or BOTTOM, not ALTERNATE since that + * makes no sense. The driver has to know whether the + * buffer represents a top or a bottom field in order to + * program any DMA correctly. Using ALTERNATE is wrong, since + * that just says that it is either a top or a bottom field, + * but not which of the two it is. + */ + dprintk(1, "the field is incorrectly set to ALTERNATE for an output buffer\n"); + return -EINVAL; + } + vb->timestamp = 0; + vbuf->sequence = 0; + + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { + if (b->memory == VB2_MEMORY_USERPTR) { + for (plane = 0; plane < vb->num_planes; ++plane) { + planes[plane].m.userptr = + b->m.planes[plane].m.userptr; + planes[plane].length = + b->m.planes[plane].length; + } + } + if (b->memory == VB2_MEMORY_DMABUF) { + for (plane = 0; plane < vb->num_planes; ++plane) { + planes[plane].m.fd = + b->m.planes[plane].m.fd; + planes[plane].length = + b->m.planes[plane].length; + } + } + + /* Fill in driver-provided information for OUTPUT types */ + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * Will have to go up to b->length when API starts + * accepting variable number of planes. + * + * If bytesused == 0 for the output buffer, then fall + * back to the full buffer size. In that case + * userspace clearly never bothered to set it and + * it's a safe assumption that they really meant to + * use the full plane sizes. + * + * Some drivers, e.g. old codec drivers, use bytesused == 0 + * as a way to indicate that streaming is finished. + * In that case, the driver should use the + * allow_zero_bytesused flag to keep old userspace + * applications working. + */ + for (plane = 0; plane < vb->num_planes; ++plane) { + struct vb2_plane *pdst = &planes[plane]; + struct v4l2_plane *psrc = &b->m.planes[plane]; + + if (psrc->bytesused == 0) + vb2_warn_zero_bytesused(vb); + + if (vb->vb2_queue->allow_zero_bytesused) + pdst->bytesused = psrc->bytesused; + else + pdst->bytesused = psrc->bytesused ? + psrc->bytesused : pdst->length; + pdst->data_offset = psrc->data_offset; + } + } + } else { + /* + * Single-planar buffers do not use planes array, + * so fill in relevant v4l2_buffer struct fields instead. + * In videobuf we use our internal V4l2_planes struct for + * single-planar buffers as well, for simplicity. + * + * If bytesused == 0 for the output buffer, then fall back + * to the full buffer size as that's a sensible default. + * + * Some drivers, e.g. old codec drivers, use bytesused == 0 as + * a way to indicate that streaming is finished. In that case, + * the driver should use the allow_zero_bytesused flag to keep + * old userspace applications working. + */ + if (b->memory == VB2_MEMORY_USERPTR) { + planes[0].m.userptr = b->m.userptr; + planes[0].length = b->length; + } + + if (b->memory == VB2_MEMORY_DMABUF) { + planes[0].m.fd = b->m.fd; + planes[0].length = b->length; + } + + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + if (b->bytesused == 0) + vb2_warn_zero_bytesused(vb); + + if (vb->vb2_queue->allow_zero_bytesused) + planes[0].bytesused = b->bytesused; + else + planes[0].bytesused = b->bytesused ? + b->bytesused : planes[0].length; + } else + planes[0].bytesused = 0; + + } + + /* Zero flags that the vb2 core handles */ + vbuf->flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS; + if (!vb->vb2_queue->copy_timestamp || !V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * Non-COPY timestamps and non-OUTPUT queues will get + * their timestamp and timestamp source flags from the + * queue. + */ + vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + } + + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * For output buffers mask out the timecode flag: + * this will be handled later in vb2_qbuf(). + * The 'field' is valid metadata for this output buffer + * and so that needs to be copied here. + */ + vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE; + vbuf->field = b->field; + } else { + /* Zero any output buffer flags as this is a capture buffer */ + vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS; + /* Zero last flag, this is a signal from driver to userspace */ + vbuf->flags &= ~V4L2_BUF_FLAG_LAST; + } + + return 0; +} + +static const struct vb2_buf_ops v4l2_buf_ops = { + .verify_planes_array = __verify_planes_array_core, + .fill_user_buffer = __fill_v4l2_buffer, + .fill_vb2_buffer = __fill_vb2_buffer, + .copy_timestamp = __copy_timestamp, +}; + +/* + * vb2_querybuf() - query video buffer information + * @q: videobuf queue + * @b: buffer struct passed from userspace to vidioc_querybuf handler + * in driver + * + * Should be called from vidioc_querybuf ioctl handler in driver. + * This function will verify the passed v4l2_buffer structure and fill the + * relevant information for the userspace. + * + * The return values from this function are intended to be directly returned + * from vidioc_querybuf handler in driver. + */ +int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + struct vb2_buffer *vb; + int ret; + + if (b->type != q->type) { + dprintk(1, "wrong buffer type\n"); + return -EINVAL; + } + + if (b->index >= q->num_buffers) { + dprintk(1, "buffer index out of range\n"); + return -EINVAL; + } + vb = q->bufs[b->index]; + ret = __verify_planes_array(vb, b); + if (!ret) + vb2_core_querybuf(q, b->index, b); + return ret; +} +EXPORT_SYMBOL(vb2_querybuf); + +int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) +{ + int ret = vb2_verify_memory_type(q, req->memory, req->type); + + return ret ? ret : vb2_core_reqbufs(q, req->memory, &req->count); +} +EXPORT_SYMBOL_GPL(vb2_reqbufs); + +int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + int ret; + + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + ret = vb2_queue_or_prepare_buf(q, b, "prepare_buf"); + + return ret ? ret : vb2_core_prepare_buf(q, b->index, b); +} +EXPORT_SYMBOL_GPL(vb2_prepare_buf); + +int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) +{ + unsigned requested_planes = 1; + unsigned requested_sizes[VIDEO_MAX_PLANES]; + struct v4l2_format *f = &create->format; + int ret = vb2_verify_memory_type(q, create->memory, f->type); + unsigned i; + + create->index = q->num_buffers; + if (create->count == 0) + return ret != -EBUSY ? ret : 0; + + switch (f->type) { + case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE: + case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE: + requested_planes = f->fmt.pix_mp.num_planes; + if (requested_planes == 0 || + requested_planes > VIDEO_MAX_PLANES) + return -EINVAL; + for (i = 0; i < requested_planes; i++) + requested_sizes[i] = + f->fmt.pix_mp.plane_fmt[i].sizeimage; + break; + case V4L2_BUF_TYPE_VIDEO_CAPTURE: + case V4L2_BUF_TYPE_VIDEO_OUTPUT: + requested_sizes[0] = f->fmt.pix.sizeimage; + break; + case V4L2_BUF_TYPE_VBI_CAPTURE: + case V4L2_BUF_TYPE_VBI_OUTPUT: + requested_sizes[0] = f->fmt.vbi.samples_per_line * + (f->fmt.vbi.count[0] + f->fmt.vbi.count[1]); + break; + case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE: + case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT: + requested_sizes[0] = f->fmt.sliced.io_size; + break; + case V4L2_BUF_TYPE_SDR_CAPTURE: + case V4L2_BUF_TYPE_SDR_OUTPUT: + requested_sizes[0] = f->fmt.sdr.buffersize; + break; + case V4L2_BUF_TYPE_META_CAPTURE: + requested_sizes[0] = f->fmt.meta.buffersize; + break; + default: + return -EINVAL; + } + for (i = 0; i < requested_planes; i++) + if (requested_sizes[i] == 0) + return -EINVAL; + return ret ? ret : vb2_core_create_bufs(q, create->memory, + &create->count, requested_planes, requested_sizes); +} +EXPORT_SYMBOL_GPL(vb2_create_bufs); + +int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + int ret; + + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + ret = vb2_queue_or_prepare_buf(q, b, "qbuf"); + return ret ? ret : vb2_core_qbuf(q, b->index, b); +} +EXPORT_SYMBOL_GPL(vb2_qbuf); + +int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) +{ + int ret; + + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + if (b->type != q->type) { + dprintk(1, "invalid buffer type\n"); + return -EINVAL; + } + + ret = vb2_core_dqbuf(q, NULL, b, nonblocking); + + /* + * After calling the VIDIOC_DQBUF V4L2_BUF_FLAG_DONE must be + * cleared. + */ + b->flags &= ~V4L2_BUF_FLAG_DONE; + + return ret; +} +EXPORT_SYMBOL_GPL(vb2_dqbuf); + +int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_core_streamon(q, type); +} +EXPORT_SYMBOL_GPL(vb2_streamon); + +int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_core_streamoff(q, type); +} +EXPORT_SYMBOL_GPL(vb2_streamoff); + +int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) +{ + return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index, + eb->plane, eb->flags); +} +EXPORT_SYMBOL_GPL(vb2_expbuf); + +int vb2_queue_init(struct vb2_queue *q) +{ + /* + * Sanity check + */ + if (WARN_ON(!q) || + WARN_ON(q->timestamp_flags & + ~(V4L2_BUF_FLAG_TIMESTAMP_MASK | + V4L2_BUF_FLAG_TSTAMP_SRC_MASK))) + return -EINVAL; + + /* Warn that the driver should choose an appropriate timestamp type */ + WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN); + + /* Warn that vb2_memory should match with v4l2_memory */ + if (WARN_ON(VB2_MEMORY_MMAP != (int)V4L2_MEMORY_MMAP) + || WARN_ON(VB2_MEMORY_USERPTR != (int)V4L2_MEMORY_USERPTR) + || WARN_ON(VB2_MEMORY_DMABUF != (int)V4L2_MEMORY_DMABUF)) + return -EINVAL; + + if (q->buf_struct_size == 0) + q->buf_struct_size = sizeof(struct vb2_v4l2_buffer); + + q->buf_ops = &v4l2_buf_ops; + q->is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type); + q->is_output = V4L2_TYPE_IS_OUTPUT(q->type); + q->copy_timestamp = (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) + == V4L2_BUF_FLAG_TIMESTAMP_COPY; + /* + * For compatibility with vb1: if QBUF hasn't been called yet, then + * return POLLERR as well. This only affects capture queues, output + * queues will always initialize waiting_for_buffers to false. + */ + q->quirk_poll_must_check_waiting_for_buffers = true; + + return vb2_core_queue_init(q); +} +EXPORT_SYMBOL_GPL(vb2_queue_init); + +void vb2_queue_release(struct vb2_queue *q) +{ + vb2_core_queue_release(q); +} +EXPORT_SYMBOL_GPL(vb2_queue_release); + +__poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) +{ + struct video_device *vfd = video_devdata(file); + __poll_t req_events = poll_requested_events(wait); + __poll_t res = 0; + + if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { + struct v4l2_fh *fh = file->private_data; + + if (v4l2_event_pending(fh)) + res = POLLPRI; + else if (req_events & POLLPRI) + poll_wait(file, &fh->wait, wait); + } + + return res | vb2_core_poll(q, file, wait); +} +EXPORT_SYMBOL_GPL(vb2_poll); + +/* + * The following functions are not part of the vb2 core API, but are helper + * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations + * and struct vb2_ops. + * They contain boilerplate code that most if not all drivers have to do + * and so they simplify the driver code. + */ + +/* The queue is busy if there is a owner and you are not that owner. */ +static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file) +{ + return vdev->queue->owner && vdev->queue->owner != file->private_data; +} + +/* vb2 ioctl helpers */ + +int vb2_ioctl_reqbufs(struct file *file, void *priv, + struct v4l2_requestbuffers *p) +{ + struct video_device *vdev = video_devdata(file); + int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); + + if (res) + return res; + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + res = vb2_core_reqbufs(vdev->queue, p->memory, &p->count); + /* If count == 0, then the owner has released all buffers and he + is no longer owner of the queue. Otherwise we have a new owner. */ + if (res == 0) + vdev->queue->owner = p->count ? file->private_data : NULL; + return res; +} +EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs); + +int vb2_ioctl_create_bufs(struct file *file, void *priv, + struct v4l2_create_buffers *p) +{ + struct video_device *vdev = video_devdata(file); + int res = vb2_verify_memory_type(vdev->queue, p->memory, + p->format.type); + + p->index = vdev->queue->num_buffers; + /* + * If count == 0, then just check if memory and type are valid. + * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0. + */ + if (p->count == 0) + return res != -EBUSY ? res : 0; + if (res) + return res; + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + + res = vb2_create_bufs(vdev->queue, p); + if (res == 0) + vdev->queue->owner = file->private_data; + return res; +} +EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs); + +int vb2_ioctl_prepare_buf(struct file *file, void *priv, + struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_prepare_buf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf); + +int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + /* No need to call vb2_queue_is_busy(), anyone can query buffers. */ + return vb2_querybuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf); + +int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_qbuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf); + +int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf); + +int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_streamon(vdev->queue, i); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_streamon); + +int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_streamoff(vdev->queue, i); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff); + +int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_expbuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf); + +/* v4l2_file_operations helpers */ + +int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct video_device *vdev = video_devdata(file); + + return vb2_mmap(vdev->queue, vma); +} +EXPORT_SYMBOL_GPL(vb2_fop_mmap); + +int _vb2_fop_release(struct file *file, struct mutex *lock) +{ + struct video_device *vdev = video_devdata(file); + + if (lock) + mutex_lock(lock); + if (file->private_data == vdev->queue->owner) { + vb2_queue_release(vdev->queue); + vdev->queue->owner = NULL; + } + if (lock) + mutex_unlock(lock); + return v4l2_fh_release(file); +} +EXPORT_SYMBOL_GPL(_vb2_fop_release); + +int vb2_fop_release(struct file *file) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + + return _vb2_fop_release(file, lock); +} +EXPORT_SYMBOL_GPL(vb2_fop_release); + +ssize_t vb2_fop_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err = -EBUSY; + + if (!(vdev->queue->io_modes & VB2_WRITE)) + return -EINVAL; + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + if (vb2_queue_is_busy(vdev, file)) + goto exit; + err = vb2_write(vdev->queue, buf, count, ppos, + file->f_flags & O_NONBLOCK); + if (vdev->queue->fileio) + vdev->queue->owner = file->private_data; +exit: + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_write); + +ssize_t vb2_fop_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err = -EBUSY; + + if (!(vdev->queue->io_modes & VB2_READ)) + return -EINVAL; + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + if (vb2_queue_is_busy(vdev, file)) + goto exit; + err = vb2_read(vdev->queue, buf, count, ppos, + file->f_flags & O_NONBLOCK); + if (vdev->queue->fileio) + vdev->queue->owner = file->private_data; +exit: + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_read); + +__poll_t vb2_fop_poll(struct file *file, poll_table *wait) +{ + struct video_device *vdev = video_devdata(file); + struct vb2_queue *q = vdev->queue; + struct mutex *lock = q->lock ? q->lock : vdev->lock; + __poll_t res; + void *fileio; + + /* + * If this helper doesn't know how to lock, then you shouldn't be using + * it but you should write your own. + */ + WARN_ON(!lock); + + if (lock && mutex_lock_interruptible(lock)) + return POLLERR; + + fileio = q->fileio; + + res = vb2_poll(vdev->queue, file, wait); + + /* If fileio was started, then we have a new queue owner. */ + if (!fileio && q->fileio) + q->owner = file->private_data; + if (lock) + mutex_unlock(lock); + return res; +} +EXPORT_SYMBOL_GPL(vb2_fop_poll); + +#ifndef CONFIG_MMU +unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct video_device *vdev = video_devdata(file); + + return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags); +} +EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area); +#endif + +/* vb2_ops helpers. Only use if vq->lock is non-NULL. */ + +void vb2_ops_wait_prepare(struct vb2_queue *vq) +{ + mutex_unlock(vq->lock); +} +EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare); + +void vb2_ops_wait_finish(struct vb2_queue *vq) +{ + mutex_lock(vq->lock); +} +EXPORT_SYMBOL_GPL(vb2_ops_wait_finish); + +MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); +MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); +MODULE_LICENSE("GPL"); |