1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
/*
*
* V 4 L 2 D R I V E R H E L P E R A P I
*
* Moved from videodev2.h
*
* Some commonly needed functions for drivers (v4l2-common.o module)
*/
#ifndef _V4L2_DEV_H
#define _V4L2_DEV_H
#include <linux/poll.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/cdev.h>
#include <linux/mutex.h>
#include <linux/videodev2.h>
#define VIDEO_MAJOR 81
#define VFL_TYPE_GRABBER 0
#define VFL_TYPE_VBI 1
#define VFL_TYPE_RADIO 2
#define VFL_TYPE_VTX 3
#define VFL_TYPE_MAX 4
struct v4l2_ioctl_callbacks;
struct video_device;
struct v4l2_device;
/* Flag to mark the video_device struct as unregistered.
Drivers can set this flag if they want to block all future
device access. It is set by video_unregister_device. */
#define V4L2_FL_UNREGISTERED (0)
struct v4l2_file_operations {
struct module *owner;
ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
unsigned int (*poll) (struct file *, struct poll_table_struct *);
int (*ioctl) (struct file *, unsigned int, unsigned long);
long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
int (*mmap) (struct file *, struct vm_area_struct *);
int (*open) (struct file *);
int (*release) (struct file *);
};
/*
* Newer version of video_device, handled by videodev2.c
* This version moves redundant code from video device code to
* the common handler
*/
struct video_device
{
/* device ops */
const struct v4l2_file_operations *fops;
/* sysfs */
struct device dev; /* v4l device */
struct cdev *cdev; /* character device */
/* Set either parent or v4l2_dev if your driver uses v4l2_device */
struct device *parent; /* device parent */
struct v4l2_device *v4l2_dev; /* v4l2_device parent */
/* device info */
char name[32];
int vfl_type;
/* 'minor' is set to -1 if the registration failed */
int minor;
u16 num;
/* use bitops to set/clear/test flags */
unsigned long flags;
/* attribute to differentiate multiple indices on one physical device */
int index;
int debug; /* Activates debug level*/
/* Video standard vars */
v4l2_std_id tvnorms; /* Supported tv norms */
v4l2_std_id current_norm; /* Current tvnorm */
/* callbacks */
void (*release)(struct video_device *vdev);
/* ioctl callbacks */
const struct v4l2_ioctl_ops *ioctl_ops;
};
/* dev to video-device */
#define to_video_device(cd) container_of(cd, struct video_device, dev)
/* Register video devices. Note that if video_register_device fails,
the release() callback of the video_device structure is *not* called, so
the caller is responsible for freeing any data. Usually that means that
you call video_device_release() on failure.
Also note that vdev->minor is set to -1 if the registration failed. */
int __must_check video_register_device(struct video_device *vdev, int type, int nr);
int __must_check video_register_device_index(struct video_device *vdev,
int type, int nr, int index);
/* Unregister video devices. Will do nothing if vdev == NULL or
vdev->minor < 0. */
void video_unregister_device(struct video_device *vdev);
/* helper functions to alloc/release struct video_device, the
latter can also be used for video_device->release(). */
struct video_device * __must_check video_device_alloc(void);
/* this release function frees the vdev pointer */
void video_device_release(struct video_device *vdev);
/* this release function does nothing, use when the video_device is a
static global struct. Note that having a static video_device is
a dubious construction at best. */
void video_device_release_empty(struct video_device *vdev);
/* helper functions to access driver private data. */
static inline void *video_get_drvdata(struct video_device *vdev)
{
return dev_get_drvdata(&vdev->dev);
}
static inline void video_set_drvdata(struct video_device *vdev, void *data)
{
dev_set_drvdata(&vdev->dev, data);
}
struct video_device *video_devdata(struct file *file);
/* Combine video_get_drvdata and video_devdata as this is
used very often. */
static inline void *video_drvdata(struct file *file)
{
return video_get_drvdata(video_devdata(file));
}
static inline int video_is_unregistered(struct video_device *vdev)
{
return test_bit(V4L2_FL_UNREGISTERED, &vdev->flags);
}
#endif /* _V4L2_DEV_H */
|
