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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;
30struct v4l2_ctrl_handler;
31
32/* Flag to mark the video_device struct as registered.
33 Drivers can clear this flag if they want to block all future
34 device access. It is cleared by video_unregister_device. */
35#define V4L2_FL_REGISTERED (0)
36#define V4L2_FL_USES_V4L2_FH (1)
37
38struct v4l2_file_operations {
39 struct module *owner;
40 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
41 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
42 unsigned int (*poll) (struct file *, struct poll_table_struct *);
43 long (*ioctl) (struct file *, unsigned int, unsigned long);
44 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
45 unsigned long (*get_unmapped_area) (struct file *, unsigned long,
46 unsigned long, unsigned long, unsigned long);
47 int (*mmap) (struct file *, struct vm_area_struct *);
48 int (*open) (struct file *);
49 int (*release) (struct file *);
50};
51
52/*
53 * Newer version of video_device, handled by videodev2.c
54 * This version moves redundant code from video device code to
55 * the common handler
56 */
57
58struct video_device
59{
60 /* device ops */
61 const struct v4l2_file_operations *fops;
62
63 /* sysfs */
64 struct device dev; /* v4l device */
65 struct cdev *cdev; /* character device */
66
67 /* Set either parent or v4l2_dev if your driver uses v4l2_device */
68 struct device *parent; /* device parent */
69 struct v4l2_device *v4l2_dev; /* v4l2_device parent */
70
71 /* Control handler associated with this device node. May be NULL. */
72 struct v4l2_ctrl_handler *ctrl_handler;
73
74 /* device info */
75 char name[32];
76 int vfl_type;
77 /* 'minor' is set to -1 if the registration failed */
78 int minor;
79 u16 num;
80 /* use bitops to set/clear/test flags */
81 unsigned long flags;
82 /* attribute to differentiate multiple indices on one physical device */
83 int index;
84
85 /* V4L2 file handles */
86 spinlock_t fh_lock; /* Lock for all v4l2_fhs */
87 struct list_head fh_list; /* List of struct v4l2_fh */
88
89 int debug; /* Activates debug level*/
90
91 /* Video standard vars */
92 v4l2_std_id tvnorms; /* Supported tv norms */
93 v4l2_std_id current_norm; /* Current tvnorm */
94
95 /* callbacks */
96 void (*release)(struct video_device *vdev);
97
98 /* ioctl callbacks */
99 const struct v4l2_ioctl_ops *ioctl_ops;
100};
101
102/* dev to video-device */
103#define to_video_device(cd) container_of(cd, struct video_device, dev)
104
105/* Register video devices. Note that if video_register_device fails,
106 the release() callback of the video_device structure is *not* called, so
107 the caller is responsible for freeing any data. Usually that means that
108 you call video_device_release() on failure. */
109int __must_check video_register_device(struct video_device *vdev, int type, int nr);
110
111/* Same as video_register_device, but no warning is issued if the desired
112 device node number was already in use. */
113int __must_check video_register_device_no_warn(struct video_device *vdev, int type, int nr);
114
115/* Unregister video devices. Will do nothing if vdev == NULL or
116 video_is_registered() returns false. */
117void video_unregister_device(struct video_device *vdev);
118
119/* helper functions to alloc/release struct video_device, the
120 latter can also be used for video_device->release(). */
121struct video_device * __must_check video_device_alloc(void);
122
123/* this release function frees the vdev pointer */
124void video_device_release(struct video_device *vdev);
125
126/* this release function does nothing, use when the video_device is a
127 static global struct. Note that having a static video_device is
128 a dubious construction at best. */
129void video_device_release_empty(struct video_device *vdev);
130
131/* helper functions to access driver private data. */
132static inline void *video_get_drvdata(struct video_device *vdev)
133{
134 return dev_get_drvdata(&vdev->dev);
135}
136
137static inline void video_set_drvdata(struct video_device *vdev, void *data)
138{
139 dev_set_drvdata(&vdev->dev, data);
140}
141
142struct video_device *video_devdata(struct file *file);
143
144/* Combine video_get_drvdata and video_devdata as this is
145 used very often. */
146static inline void *video_drvdata(struct file *file)
147{
148 return video_get_drvdata(video_devdata(file));
149}
150
151static inline const char *video_device_node_name(struct video_device *vdev)
152{
153 return dev_name(&vdev->dev);
154}
155
156static inline int video_is_registered(struct video_device *vdev)
157{
158 return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
159}
160
161#endif /* _V4L2_DEV_H */