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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 registered.
32 Drivers can clear this flag if they want to block all future
33 device access. It is cleared by video_unregister_device. */
34#define V4L2_FL_REGISTERED (0)
35#define V4L2_FL_USES_V4L2_FH (1)
36
37struct v4l2_file_operations {
38 struct module *owner;
39 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
40 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
41 unsigned int (*poll) (struct file *, struct poll_table_struct *);
42 long (*ioctl) (struct file *, unsigned int, unsigned long);
43 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
44 unsigned long (*get_unmapped_area) (struct file *, unsigned long,
45 unsigned long, unsigned long, unsigned long);
46 int (*mmap) (struct file *, struct vm_area_struct *);
47 int (*open) (struct file *);
48 int (*release) (struct file *);
49};
50
51/*
52 * Newer version of video_device, handled by videodev2.c
53 * This version moves redundant code from video device code to
54 * the common handler
55 */
56
57struct video_device
58{
59 /* device ops */
60 const struct v4l2_file_operations *fops;
61
62 /* sysfs */
63 struct device dev; /* v4l device */
64 struct cdev *cdev; /* character device */
65
66 /* Set either parent or v4l2_dev if your driver uses v4l2_device */
67 struct device *parent; /* device parent */
68 struct v4l2_device *v4l2_dev; /* v4l2_device parent */
69
70 /* device info */
71 char name[32];
72 int vfl_type;
73 /* 'minor' is set to -1 if the registration failed */
74 int minor;
75 u16 num;
76 /* use bitops to set/clear/test flags */
77 unsigned long flags;
78 /* attribute to differentiate multiple indices on one physical device */
79 int index;
80
81 /* V4L2 file handles */
82 spinlock_t fh_lock; /* Lock for all v4l2_fhs */
83 struct list_head fh_list; /* List of struct v4l2_fh */
84
85 int debug; /* Activates debug level*/
86
87 /* Video standard vars */
88 v4l2_std_id tvnorms; /* Supported tv norms */
89 v4l2_std_id current_norm; /* Current tvnorm */
90
91 /* callbacks */
92 void (*release)(struct video_device *vdev);
93
94 /* ioctl callbacks */
95 const struct v4l2_ioctl_ops *ioctl_ops;
96};
97
98/* dev to video-device */
99#define to_video_device(cd) container_of(cd, struct video_device, dev)
100
101/* Register video devices. Note that if video_register_device fails,
102 the release() callback of the video_device structure is *not* called, so
103 the caller is responsible for freeing any data. Usually that means that
104 you call video_device_release() on failure. */
105int __must_check video_register_device(struct video_device *vdev, int type, int nr);
106
107/* Same as video_register_device, but no warning is issued if the desired
108 device node number was already in use. */
109int __must_check video_register_device_no_warn(struct video_device *vdev, int type, int nr);
110
111/* Unregister video devices. Will do nothing if vdev == NULL or
112 video_is_registered() returns false. */
113void video_unregister_device(struct video_device *vdev);
114
115/* helper functions to alloc/release struct video_device, the
116 latter can also be used for video_device->release(). */
117struct video_device * __must_check video_device_alloc(void);
118
119/* this release function frees the vdev pointer */
120void video_device_release(struct video_device *vdev);
121
122/* this release function does nothing, use when the video_device is a
123 static global struct. Note that having a static video_device is
124 a dubious construction at best. */
125void video_device_release_empty(struct video_device *vdev);
126
127/* helper functions to access driver private data. */
128static inline void *video_get_drvdata(struct video_device *vdev)
129{
130 return dev_get_drvdata(&vdev->dev);
131}
132
133static inline void video_set_drvdata(struct video_device *vdev, void *data)
134{
135 dev_set_drvdata(&vdev->dev, data);
136}
137
138struct video_device *video_devdata(struct file *file);
139
140/* Combine video_get_drvdata and video_devdata as this is
141 used very often. */
142static inline void *video_drvdata(struct file *file)
143{
144 return video_get_drvdata(video_devdata(file));
145}
146
147static inline const char *video_device_node_name(struct video_device *vdev)
148{
149 return dev_name(&vdev->dev);
150}
151
152static inline int video_is_registered(struct video_device *vdev)
153{
154 return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
155}
156
157#endif /* _V4L2_DEV_H */