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