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1/*
2 *
3 * V 4 L 2 D R I V E R H E L P E R A P I
4 *
5 * Moved from videodev2.h
6 *
7 * Some commonly needed functions for drivers (v4l2-common.o module)
8 */
9#ifndef _V4L2_DEV_H
10#define _V4L2_DEV_H
11
12#include <linux/poll.h>
13#include <linux/fs.h>
14#include <linux/device.h>
15#include <linux/cdev.h>
16#include <linux/mutex.h>
17#include <linux/videodev2.h>
18
19#define VIDEO_MAJOR 81
20
21#define VFL_TYPE_GRABBER 0
22#define VFL_TYPE_VBI 1
23#define VFL_TYPE_RADIO 2
24#define VFL_TYPE_VTX 3
25#define VFL_TYPE_MAX 4
26
27struct v4l2_ioctl_callbacks;
28struct video_device;
29struct v4l2_device;
30
31/* Flag to mark the video_device struct as unregistered.
32 Drivers can set this flag if they want to block all future
33 device access. It is set by video_unregister_device. */
34#define V4L2_FL_UNREGISTERED (0)
35
36struct v4l2_file_operations {
37 struct module *owner;
38 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
39 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
40 unsigned int (*poll) (struct file *, struct poll_table_struct *);
41 long (*ioctl) (struct file *, unsigned int, unsigned long);
42 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
43 unsigned long (*get_unmapped_area) (struct file *, unsigned long,
44 unsigned long, unsigned long, unsigned long);
45 int (*mmap) (struct file *, struct vm_area_struct *);
46 int (*open) (struct file *);
47 int (*release) (struct file *);
48};
49
50/*
51 * Newer version of video_device, handled by videodev2.c
52 * This version moves redundant code from video device code to
53 * the common handler
54 */
55
56struct video_device
57{
58 /* device ops */
59 const struct v4l2_file_operations *fops;
60
61 /* sysfs */
62 struct device dev; /* v4l device */
63 struct cdev *cdev; /* character device */
64
65 /* Set either parent or v4l2_dev if your driver uses v4l2_device */
66 struct device *parent; /* device parent */
67 struct v4l2_device *v4l2_dev; /* v4l2_device parent */
68
69 /* device info */
70 char name[32];
71 int vfl_type;
72 /* 'minor' is set to -1 if the registration failed */
73 int minor;
74 u16 num;
75 /* use bitops to set/clear/test flags */
76 unsigned long flags;
77 /* attribute to differentiate multiple indices on one physical device */
78 int index;
79
80 int debug; /* Activates debug level*/
81
82 /* Video standard vars */
83 v4l2_std_id tvnorms; /* Supported tv norms */
84 v4l2_std_id current_norm; /* Current tvnorm */
85
86 /* callbacks */
87 void (*release)(struct video_device *vdev);
88
89 /* ioctl callbacks */
90 const struct v4l2_ioctl_ops *ioctl_ops;
91};
92
93/* dev to video-device */
94#define to_video_device(cd) container_of(cd, struct video_device, dev)
95
96/* Register video devices. Note that if video_register_device fails,
97 the release() callback of the video_device structure is *not* called, so
98 the caller is responsible for freeing any data. Usually that means that
99 you call video_device_release() on failure.
100
101 Also note that vdev->minor is set to -1 if the registration failed. */
102int __must_check video_register_device(struct video_device *vdev, int type, int nr);
103
104/* Same as video_register_device, but no warning is issued if the desired
105 device node number was already in use. */
106int __must_check video_register_device_no_warn(struct video_device *vdev, int type, int nr);
107
108/* Unregister video devices. Will do nothing if vdev == NULL or
109 vdev->minor < 0. */
110void video_unregister_device(struct video_device *vdev);
111
112/* helper functions to alloc/release struct video_device, the
113 latter can also be used for video_device->release(). */
114struct video_device * __must_check video_device_alloc(void);
115
116/* this release function frees the vdev pointer */
117void video_device_release(struct video_device *vdev);
118
119/* this release function does nothing, use when the video_device is a
120 static global struct. Note that having a static video_device is
121 a dubious construction at best. */
122void video_device_release_empty(struct video_device *vdev);
123
124/* helper functions to access driver private data. */
125static inline void *video_get_drvdata(struct video_device *vdev)
126{
127 return dev_get_drvdata(&vdev->dev);
128}
129
130static inline void video_set_drvdata(struct video_device *vdev, void *data)
131{
132 dev_set_drvdata(&vdev->dev, data);
133}
134
135struct video_device *video_devdata(struct file *file);
136
137/* Combine video_get_drvdata and video_devdata as this is
138 used very often. */
139static inline void *video_drvdata(struct file *file)
140{
141 return video_get_drvdata(video_devdata(file));
142}
143
144static inline int video_is_unregistered(struct video_device *vdev)
145{
146 return test_bit(V4L2_FL_UNREGISTERED, &vdev->flags);
147}
148
149#endif /* _V4L2_DEV_H */