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 #include <media/media-entity.h>
21 #define VIDEO_MAJOR 81
23 #define VFL_TYPE_GRABBER 0
24 #define VFL_TYPE_VBI 1
25 #define VFL_TYPE_RADIO 2
26 #define VFL_TYPE_SUBDEV 3
27 #define VFL_TYPE_MAX 4
29 struct v4l2_ioctl_callbacks
;
32 struct v4l2_ctrl_handler
;
34 /* Flag to mark the video_device struct as registered.
35 Drivers can clear this flag if they want to block all future
36 device access. It is cleared by video_unregister_device. */
37 #define V4L2_FL_REGISTERED (0)
38 /* file->private_data points to struct v4l2_fh */
39 #define V4L2_FL_USES_V4L2_FH (1)
40 /* Use the prio field of v4l2_fh for core priority checking */
41 #define V4L2_FL_USE_FH_PRIO (2)
42 /* If ioctl core locking is in use, then apply that also to all
43 file operations. Don't use this flag in new drivers! */
44 #define V4L2_FL_LOCK_ALL_FOPS (3)
46 /* Priority helper functions */
48 struct v4l2_prio_state
{
52 void v4l2_prio_init(struct v4l2_prio_state
*global
);
53 int v4l2_prio_change(struct v4l2_prio_state
*global
, enum v4l2_priority
*local
,
54 enum v4l2_priority
new);
55 void v4l2_prio_open(struct v4l2_prio_state
*global
, enum v4l2_priority
*local
);
56 void v4l2_prio_close(struct v4l2_prio_state
*global
, enum v4l2_priority local
);
57 enum v4l2_priority
v4l2_prio_max(struct v4l2_prio_state
*global
);
58 int v4l2_prio_check(struct v4l2_prio_state
*global
, enum v4l2_priority local
);
61 struct v4l2_file_operations
{
63 ssize_t (*read
) (struct file
*, char __user
*, size_t, loff_t
*);
64 ssize_t (*write
) (struct file
*, const char __user
*, size_t, loff_t
*);
65 unsigned int (*poll
) (struct file
*, struct poll_table_struct
*);
66 long (*ioctl
) (struct file
*, unsigned int, unsigned long);
67 long (*unlocked_ioctl
) (struct file
*, unsigned int, unsigned long);
69 long (*compat_ioctl32
) (struct file
*, unsigned int, unsigned long);
71 unsigned long (*get_unmapped_area
) (struct file
*, unsigned long,
72 unsigned long, unsigned long, unsigned long);
73 int (*mmap
) (struct file
*, struct vm_area_struct
*);
74 int (*open
) (struct file
*);
75 int (*release
) (struct file
*);
79 * Newer version of video_device, handled by videodev2.c
80 * This version moves redundant code from video device code to
86 #if defined(CONFIG_MEDIA_CONTROLLER)
87 struct media_entity entity
;
90 const struct v4l2_file_operations
*fops
;
93 struct device dev
; /* v4l device */
94 struct cdev
*cdev
; /* character device */
96 /* Set either parent or v4l2_dev if your driver uses v4l2_device */
97 struct device
*parent
; /* device parent */
98 struct v4l2_device
*v4l2_dev
; /* v4l2_device parent */
100 /* Control handler associated with this device node. May be NULL. */
101 struct v4l2_ctrl_handler
*ctrl_handler
;
103 /* Priority state. If NULL, then v4l2_dev->prio will be used. */
104 struct v4l2_prio_state
*prio
;
109 /* 'minor' is set to -1 if the registration failed */
112 /* use bitops to set/clear/test flags */
114 /* attribute to differentiate multiple indices on one physical device */
117 /* V4L2 file handles */
118 spinlock_t fh_lock
; /* Lock for all v4l2_fhs */
119 struct list_head fh_list
; /* List of struct v4l2_fh */
121 int debug
; /* Activates debug level*/
123 /* Video standard vars */
124 v4l2_std_id tvnorms
; /* Supported tv norms */
125 v4l2_std_id current_norm
; /* Current tvnorm */
128 void (*release
)(struct video_device
*vdev
);
130 /* ioctl callbacks */
131 const struct v4l2_ioctl_ops
*ioctl_ops
;
132 DECLARE_BITMAP(valid_ioctls
, BASE_VIDIOC_PRIVATE
);
134 /* serialization lock */
135 DECLARE_BITMAP(disable_locking
, BASE_VIDIOC_PRIVATE
);
139 #define media_entity_to_video_device(__e) \
140 container_of(__e, struct video_device, entity)
141 /* dev to video-device */
142 #define to_video_device(cd) container_of(cd, struct video_device, dev)
144 int __must_check
__video_register_device(struct video_device
*vdev
, int type
,
145 int nr
, int warn_if_nr_in_use
, struct module
*owner
);
147 /* Register video devices. Note that if video_register_device fails,
148 the release() callback of the video_device structure is *not* called, so
149 the caller is responsible for freeing any data. Usually that means that
150 you call video_device_release() on failure. */
151 static inline int __must_check
video_register_device(struct video_device
*vdev
,
154 return __video_register_device(vdev
, type
, nr
, 1, vdev
->fops
->owner
);
157 /* Same as video_register_device, but no warning is issued if the desired
158 device node number was already in use. */
159 static inline int __must_check
video_register_device_no_warn(
160 struct video_device
*vdev
, int type
, int nr
)
162 return __video_register_device(vdev
, type
, nr
, 0, vdev
->fops
->owner
);
165 /* Unregister video devices. Will do nothing if vdev == NULL or
166 video_is_registered() returns false. */
167 void video_unregister_device(struct video_device
*vdev
);
169 /* helper functions to alloc/release struct video_device, the
170 latter can also be used for video_device->release(). */
171 struct video_device
* __must_check
video_device_alloc(void);
173 /* this release function frees the vdev pointer */
174 void video_device_release(struct video_device
*vdev
);
176 /* this release function does nothing, use when the video_device is a
177 static global struct. Note that having a static video_device is
178 a dubious construction at best. */
179 void video_device_release_empty(struct video_device
*vdev
);
181 /* returns true if cmd is a known V4L2 ioctl */
182 bool v4l2_is_known_ioctl(unsigned int cmd
);
184 /* mark that this command shouldn't use core locking */
185 static inline void v4l2_disable_ioctl_locking(struct video_device
*vdev
, unsigned int cmd
)
187 if (_IOC_NR(cmd
) < BASE_VIDIOC_PRIVATE
)
188 set_bit(_IOC_NR(cmd
), vdev
->disable_locking
);
191 /* Mark that this command isn't implemented. This must be called before
192 video_device_register. See also the comments in determine_valid_ioctls().
193 This function allows drivers to provide just one v4l2_ioctl_ops struct, but
194 disable ioctls based on the specific card that is actually found. */
195 static inline void v4l2_disable_ioctl(struct video_device
*vdev
, unsigned int cmd
)
197 if (_IOC_NR(cmd
) < BASE_VIDIOC_PRIVATE
)
198 set_bit(_IOC_NR(cmd
), vdev
->valid_ioctls
);
201 /* helper functions to access driver private data. */
202 static inline void *video_get_drvdata(struct video_device
*vdev
)
204 return dev_get_drvdata(&vdev
->dev
);
207 static inline void video_set_drvdata(struct video_device
*vdev
, void *data
)
209 dev_set_drvdata(&vdev
->dev
, data
);
212 struct video_device
*video_devdata(struct file
*file
);
214 /* Combine video_get_drvdata and video_devdata as this is
216 static inline void *video_drvdata(struct file
*file
)
218 return video_get_drvdata(video_devdata(file
));
221 static inline const char *video_device_node_name(struct video_device
*vdev
)
223 return dev_name(&vdev
->dev
);
226 static inline int video_is_registered(struct video_device
*vdev
)
228 return test_bit(V4L2_FL_REGISTERED
, &vdev
->flags
);
231 #endif /* _V4L2_DEV_H */