include/media/videobuf2-v4l2.h

   1 /*
   2  * videobuf2-v4l2.h - V4L2 driver helper framework
   3  *
   4  * Copyright (C) 2010 Samsung Electronics
   5  *
   6  * Author: Pawel Osciak <pawel@osciak.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation.
  11  */
  12 #ifndef _MEDIA_VIDEOBUF2_V4L2_H
  13 #define _MEDIA_VIDEOBUF2_V4L2_H
  14
  15 #include <linux/videodev2.h>
  16 #include <media/videobuf2-core.h>
  17
  18 #if VB2_MAX_FRAME != VIDEO_MAX_FRAME
  19 #error VB2_MAX_FRAME != VIDEO_MAX_FRAME
  20 #endif
  21
  22 #if VB2_MAX_PLANES != VIDEO_MAX_PLANES
  23 #error VB2_MAX_PLANES != VIDEO_MAX_PLANES
  24 #endif
  25
  26 /**
  27  * struct vb2_v4l2_buffer - video buffer information for v4l2
  28  * @vb2_buf:    video buffer 2
  29  * @flags:      buffer informational flags
  30  * @field:      enum v4l2_field; field order of the image in the buffer
  31  * @timestamp:  frame timestamp
  32  * @timecode:   frame timecode
  33  * @sequence:   sequence count of this frame
  34  * Should contain enough information to be able to cover all the fields
  35  * of struct v4l2_buffer at videodev2.h
  36  */
  37 struct vb2_v4l2_buffer {
  38         struct vb2_buffer       vb2_buf;
  39
  40         __u32                   flags;
  41         __u32                   field;
  42         struct timeval          timestamp;
  43         struct v4l2_timecode    timecode;
  44         __u32                   sequence;
  45 };
  46
  47 /*
  48  * to_vb2_v4l2_buffer() - cast struct vb2_buffer * to struct vb2_v4l2_buffer *
  49  */
  50 #define to_vb2_v4l2_buffer(vb) \
  51         container_of(vb, struct vb2_v4l2_buffer, vb2_buf)
  52
  53 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
  54 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);
  55
  56 int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create);
  57 int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b);
  58
  59 int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b);
  60 int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb);
  61 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);
  62
  63 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
  64 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);
  65
  66 int __must_check vb2_queue_init(struct vb2_queue *q);
  67 void vb2_queue_release(struct vb2_queue *q);
  68
  69 unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait);
  70 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
  71                 loff_t *ppos, int nonblock);
  72 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
  73                 loff_t *ppos, int nonblock);
  74
  75 /*
  76  * vb2_thread_fnc - callback function for use with vb2_thread
  77  *
  78  * This is called whenever a buffer is dequeued in the thread.
  79  */
  80 typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv);
  81
  82 /**
  83  * vb2_thread_start() - start a thread for the given queue.
  84  * @q:          videobuf queue
  85  * @fnc:        callback function
  86  * @priv:       priv pointer passed to the callback function
  87  * @thread_name:the name of the thread. This will be prefixed with "vb2-".
  88  *
  89  * This starts a thread that will queue and dequeue until an error occurs
  90  * or @vb2_thread_stop is called.
  91  *
  92  * This function should not be used for anything else but the videobuf2-dvb
  93  * support. If you think you have another good use-case for this, then please
  94  * contact the linux-media mailinglist first.
  95  */
  96 int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv,
  97                      const char *thread_name);
  98
  99 /**
 100  * vb2_thread_stop() - stop the thread for the given queue.
 101  * @q:          videobuf queue
 102  */
 103 int vb2_thread_stop(struct vb2_queue *q);
 104
 105 /*
 106  * The following functions are not part of the vb2 core API, but are simple
 107  * helper functions that you can use in your struct v4l2_file_operations,
 108  * struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock
 109  * or video_device->lock is set, and they will set and test vb2_queue->owner
 110  * to check if the calling filehandle is permitted to do the queuing operation.
 111  */
 112
 113 /* struct v4l2_ioctl_ops helpers */
 114
 115 int vb2_ioctl_reqbufs(struct file *file, void *priv,
 116                           struct v4l2_requestbuffers *p);
 117 int vb2_ioctl_create_bufs(struct file *file, void *priv,
 118                           struct v4l2_create_buffers *p);
 119 int vb2_ioctl_prepare_buf(struct file *file, void *priv,
 120                           struct v4l2_buffer *p);
 121 int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p);
 122 int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p);
 123 int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p);
 124 int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i);
 125 int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i);
 126 int vb2_ioctl_expbuf(struct file *file, void *priv,
 127         struct v4l2_exportbuffer *p);
 128
 129 /* struct v4l2_file_operations helpers */
 130
 131 int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma);
 132 int vb2_fop_release(struct file *file);
 133 int _vb2_fop_release(struct file *file, struct mutex *lock);
 134 ssize_t vb2_fop_write(struct file *file, const char __user *buf,
 135                 size_t count, loff_t *ppos);
 136 ssize_t vb2_fop_read(struct file *file, char __user *buf,
 137                 size_t count, loff_t *ppos);
 138 unsigned int vb2_fop_poll(struct file *file, poll_table *wait);
 139 #ifndef CONFIG_MMU
 140 unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
 141                 unsigned long len, unsigned long pgoff, unsigned long flags);
 142 #endif
 143
 144 /* struct vb2_ops helpers, only use if vq->lock is non-NULL. */
 145
 146 void vb2_ops_wait_prepare(struct vb2_queue *vq);
 147 void vb2_ops_wait_finish(struct vb2_queue *vq);
 148
 149 #endif /* _MEDIA_VIDEOBUF2_V4L2_H */