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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#include <media/media-entity.h>
20
21#define VIDEO_MAJOR 81
22
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
28
29/* Is this a receiver, transmitter or mem-to-mem? */
30/* Ignored for VFL_TYPE_SUBDEV. */
31#define VFL_DIR_RX 0
32#define VFL_DIR_TX 1
33#define VFL_DIR_M2M 2
34
35struct v4l2_ioctl_callbacks;
36struct video_device;
37struct v4l2_device;
38struct v4l2_ctrl_handler;
39
40/* Flag to mark the video_device struct as registered.
41 Drivers can clear this flag if they want to block all future
42 device access. It is cleared by video_unregister_device. */
43#define V4L2_FL_REGISTERED (0)
44/* file->private_data points to struct v4l2_fh */
45#define V4L2_FL_USES_V4L2_FH (1)
46/* Use the prio field of v4l2_fh for core priority checking */
47#define V4L2_FL_USE_FH_PRIO (2)
48
49/* Priority helper functions */
50
51struct v4l2_prio_state {
52 atomic_t prios[4];
53};
54
55void v4l2_prio_init(struct v4l2_prio_state *global);
56int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
57 enum v4l2_priority new);
58void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
59void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
60enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
61int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
62
63
64struct v4l2_file_operations {
65 struct module *owner;
66 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
67 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
68 unsigned int (*poll) (struct file *, struct poll_table_struct *);
69 long (*ioctl) (struct file *, unsigned int, unsigned long);
70 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
71#ifdef CONFIG_COMPAT
72 long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);
73#endif
74 unsigned long (*get_unmapped_area) (struct file *, unsigned long,
75 unsigned long, unsigned long, unsigned long);
76 int (*mmap) (struct file *, struct vm_area_struct *);
77 int (*open) (struct file *);
78 int (*release) (struct file *);
79};
80
81/*
82 * Newer version of video_device, handled by videodev2.c
83 * This version moves redundant code from video device code to
84 * the common handler
85 */
86
87struct video_device
88{
89#if defined(CONFIG_MEDIA_CONTROLLER)
90 struct media_entity entity;
91#endif
92 /* device ops */
93 const struct v4l2_file_operations *fops;
94
95 /* sysfs */
96 struct device dev; /* v4l device */
97 struct cdev *cdev; /* character device */
98
99 /* Set either parent or v4l2_dev if your driver uses v4l2_device */
100 struct device *parent; /* device parent */
101 struct v4l2_device *v4l2_dev; /* v4l2_device parent */
102
103 /* Control handler associated with this device node. May be NULL. */
104 struct v4l2_ctrl_handler *ctrl_handler;
105
106 /* vb2_queue associated with this device node. May be NULL. */
107 struct vb2_queue *queue;
108
109 /* Priority state. If NULL, then v4l2_dev->prio will be used. */
110 struct v4l2_prio_state *prio;
111
112 /* device info */
113 char name[32];
114 int vfl_type; /* device type */
115 int vfl_dir; /* receiver, transmitter or m2m */
116 /* 'minor' is set to -1 if the registration failed */
117 int minor;
118 u16 num;
119 /* use bitops to set/clear/test flags */
120 unsigned long flags;
121 /* attribute to differentiate multiple indices on one physical device */
122 int index;
123
124 /* V4L2 file handles */
125 spinlock_t fh_lock; /* Lock for all v4l2_fhs */
126 struct list_head fh_list; /* List of struct v4l2_fh */
127
128 int debug; /* Activates debug level*/
129
130 /* Video standard vars */
131 v4l2_std_id tvnorms; /* Supported tv norms */
132 v4l2_std_id current_norm; /* Current tvnorm */
133
134 /* callbacks */
135 void (*release)(struct video_device *vdev);
136
137 /* ioctl callbacks */
138 const struct v4l2_ioctl_ops *ioctl_ops;
139 DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
140
141 /* serialization lock */
142 DECLARE_BITMAP(disable_locking, BASE_VIDIOC_PRIVATE);
143 struct mutex *lock;
144};
145
146#define media_entity_to_video_device(__e) \
147 container_of(__e, struct video_device, entity)
148/* dev to video-device */
149#define to_video_device(cd) container_of(cd, struct video_device, dev)
150
151int __must_check __video_register_device(struct video_device *vdev, int type,
152 int nr, int warn_if_nr_in_use, struct module *owner);
153
154/* Register video devices. Note that if video_register_device fails,
155 the release() callback of the video_device structure is *not* called, so
156 the caller is responsible for freeing any data. Usually that means that
157 you call video_device_release() on failure. */
158static inline int __must_check video_register_device(struct video_device *vdev,
159 int type, int nr)
160{
161 return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
162}
163
164/* Same as video_register_device, but no warning is issued if the desired
165 device node number was already in use. */
166static inline int __must_check video_register_device_no_warn(
167 struct video_device *vdev, int type, int nr)
168{
169 return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
170}
171
172/* Unregister video devices. Will do nothing if vdev == NULL or
173 video_is_registered() returns false. */
174void video_unregister_device(struct video_device *vdev);
175
176/* helper functions to alloc/release struct video_device, the
177 latter can also be used for video_device->release(). */
178struct video_device * __must_check video_device_alloc(void);
179
180/* this release function frees the vdev pointer */
181void video_device_release(struct video_device *vdev);
182
183/* this release function does nothing, use when the video_device is a
184 static global struct. Note that having a static video_device is
185 a dubious construction at best. */
186void video_device_release_empty(struct video_device *vdev);
187
188/* returns true if cmd is a known V4L2 ioctl */
189bool v4l2_is_known_ioctl(unsigned int cmd);
190
191/* mark that this command shouldn't use core locking */
192static inline void v4l2_disable_ioctl_locking(struct video_device *vdev, unsigned int cmd)
193{
194 if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
195 set_bit(_IOC_NR(cmd), vdev->disable_locking);
196}
197
198/* Mark that this command isn't implemented. This must be called before
199 video_device_register. See also the comments in determine_valid_ioctls().
200 This function allows drivers to provide just one v4l2_ioctl_ops struct, but
201 disable ioctls based on the specific card that is actually found. */
202static inline void v4l2_disable_ioctl(struct video_device *vdev, unsigned int cmd)
203{
204 if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
205 set_bit(_IOC_NR(cmd), vdev->valid_ioctls);
206}
207
208/* helper functions to access driver private data. */
209static inline void *video_get_drvdata(struct video_device *vdev)
210{
211 return dev_get_drvdata(&vdev->dev);
212}
213
214static inline void video_set_drvdata(struct video_device *vdev, void *data)
215{
216 dev_set_drvdata(&vdev->dev, data);
217}
218
219struct video_device *video_devdata(struct file *file);
220
221/* Combine video_get_drvdata and video_devdata as this is
222 used very often. */
223static inline void *video_drvdata(struct file *file)
224{
225 return video_get_drvdata(video_devdata(file));
226}
227
228static inline const char *video_device_node_name(struct video_device *vdev)
229{
230 return dev_name(&vdev->dev);
231}
232
233static inline int video_is_registered(struct video_device *vdev)
234{
235 return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
236}
237
238#endif /* _V4L2_DEV_H */