3 * V 4 L 2 D R I V E R H E L P E R A P I
5 * Moved from videodev2.h
7 * Some commonly needed functions for drivers (v4l2-common.o module)
12 #include <linux/poll.h>
14 #include <linux/device.h>
15 #include <linux/cdev.h>
16 #include <linux/mutex.h>
17 #include <linux/videodev2.h>
19 #define VIDEO_MAJOR 81
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
27 struct v4l2_ioctl_callbacks
;
30 struct v4l2_ctrl_handler
;
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)
38 struct v4l2_file_operations
{
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
*);
53 * Newer version of video_device, handled by videodev2.c
54 * This version moves redundant code from video device code to
61 const struct v4l2_file_operations
*fops
;
64 struct device dev
; /* v4l device */
65 struct cdev
*cdev
; /* character device */
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 */
71 /* Control handler associated with this device node. May be NULL. */
72 struct v4l2_ctrl_handler
*ctrl_handler
;
77 /* 'minor' is set to -1 if the registration failed */
80 /* use bitops to set/clear/test flags */
82 /* attribute to differentiate multiple indices on one physical device */
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 */
89 int debug
; /* Activates debug level*/
91 /* Video standard vars */
92 v4l2_std_id tvnorms
; /* Supported tv norms */
93 v4l2_std_id current_norm
; /* Current tvnorm */
96 void (*release
)(struct video_device
*vdev
);
99 const struct v4l2_ioctl_ops
*ioctl_ops
;
102 /* dev to video-device */
103 #define to_video_device(cd) container_of(cd, struct video_device, dev)
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. */
109 int __must_check
video_register_device(struct video_device
*vdev
, int type
, int nr
);
111 /* Same as video_register_device, but no warning is issued if the desired
112 device node number was already in use. */
113 int __must_check
video_register_device_no_warn(struct video_device
*vdev
, int type
, int nr
);
115 /* Unregister video devices. Will do nothing if vdev == NULL or
116 video_is_registered() returns false. */
117 void video_unregister_device(struct video_device
*vdev
);
119 /* helper functions to alloc/release struct video_device, the
120 latter can also be used for video_device->release(). */
121 struct video_device
* __must_check
video_device_alloc(void);
123 /* this release function frees the vdev pointer */
124 void video_device_release(struct video_device
*vdev
);
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. */
129 void video_device_release_empty(struct video_device
*vdev
);
131 /* helper functions to access driver private data. */
132 static inline void *video_get_drvdata(struct video_device
*vdev
)
134 return dev_get_drvdata(&vdev
->dev
);
137 static inline void video_set_drvdata(struct video_device
*vdev
, void *data
)
139 dev_set_drvdata(&vdev
->dev
, data
);
142 struct video_device
*video_devdata(struct file
*file
);
144 /* Combine video_get_drvdata and video_devdata as this is
146 static inline void *video_drvdata(struct file
*file
)
148 return video_get_drvdata(video_devdata(file
));
151 static inline const char *video_device_node_name(struct video_device
*vdev
)
153 return dev_name(&vdev
->dev
);
156 static inline int video_is_registered(struct video_device
*vdev
)
158 return test_bit(V4L2_FL_REGISTERED
, &vdev
->flags
);
161 #endif /* _V4L2_DEV_H */