blob: 5abab1e7c7e869225bd546b363e54400444fc1fe [file] [log] [blame]
* videobuf2-v4l2.h - V4L2 driver helper framework
* Copyright (C) 2010 Samsung Electronics
* Author: Pawel Osciak <>
* 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/videodev2.h>
#include <media/videobuf2-core.h>
* struct vb2_v4l2_buffer - video buffer information for v4l2
* @vb2_buf: video buffer 2
* @flags: buffer informational flags
* @field: enum v4l2_field; field order of the image in the buffer
* @timestamp: frame timestamp
* @timecode: frame timecode
* @sequence: sequence count of this frame
* Should contain enough information to be able to cover all the fields
* of struct v4l2_buffer at videodev2.h
struct vb2_v4l2_buffer {
struct vb2_buffer vb2_buf;
__u32 flags;
__u32 field;
struct timeval timestamp;
struct v4l2_timecode timecode;
__u32 sequence;
* to_vb2_v4l2_buffer() - cast struct vb2_buffer * to struct vb2_v4l2_buffer *
#define to_vb2_v4l2_buffer(vb) \
container_of(vb, struct vb2_v4l2_buffer, vb2_buf)
int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);
int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create);
int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b);
int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b);
int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb);
int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);
int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);
int __must_check vb2_queue_init(struct vb2_queue *q);
void vb2_queue_release(struct vb2_queue *q);
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait);
size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
loff_t *ppos, int nonblock);
size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
loff_t *ppos, int nonblock);
* vb2_thread_fnc - callback function for use with vb2_thread
* This is called whenever a buffer is dequeued in the thread.
typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv);
* vb2_thread_start() - start a thread for the given queue.
* @q: videobuf queue
* @fnc: callback function
* @priv: priv pointer passed to the callback function
* @thread_name:the name of the thread. This will be prefixed with "vb2-".
* This starts a thread that will queue and dequeue until an error occurs
* or @vb2_thread_stop is called.
* This function should not be used for anything else but the videobuf2-dvb
* support. If you think you have another good use-case for this, then please
* contact the linux-media mailinglist first.
int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv,
const char *thread_name);
* vb2_thread_stop() - stop the thread for the given queue.
* @q: videobuf queue
int vb2_thread_stop(struct vb2_queue *q);
* The following functions are not part of the vb2 core API, but are simple
* helper functions that you can use in your struct v4l2_file_operations,
* struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock
* or video_device->lock is set, and they will set and test vb2_queue->owner
* to check if the calling filehandle is permitted to do the queuing operation.
/* struct v4l2_ioctl_ops helpers */
int vb2_ioctl_reqbufs(struct file *file, void *priv,
struct v4l2_requestbuffers *p);
int vb2_ioctl_create_bufs(struct file *file, void *priv,
struct v4l2_create_buffers *p);
int vb2_ioctl_prepare_buf(struct file *file, void *priv,
struct v4l2_buffer *p);
int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p);
int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p);
int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p);
int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i);
int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i);
int vb2_ioctl_expbuf(struct file *file, void *priv,
struct v4l2_exportbuffer *p);
/* struct v4l2_file_operations helpers */
int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma);
int vb2_fop_release(struct file *file);
int _vb2_fop_release(struct file *file, struct mutex *lock);
ssize_t vb2_fop_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos);
ssize_t vb2_fop_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos);
unsigned int vb2_fop_poll(struct file *file, poll_table *wait);
#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 vb2_ops helpers, only use if vq->lock is non-NULL. */
void vb2_ops_wait_prepare(struct vb2_queue *vq);
void vb2_ops_wait_finish(struct vb2_queue *vq);
#endif /* _MEDIA_VIDEOBUF2_V4L2_H */