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/*
*
* V 4 L 2 D R I V E R H E L P E R A P I
*
* Moved from videodev2.h
*
* Some commonly needed functions for drivers (v4l2-common.o module)
*/
#ifndef _V4L2_DEV_H
#define _V4L2_DEV_H
#include <linux/poll.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/cdev.h>
#include <linux/mutex.h>
#include <linux/videodev2.h>
#define VIDEO_MAJOR 81
#define VFL_TYPE_GRABBER 0
#define VFL_TYPE_VBI 1
#define VFL_TYPE_RADIO 2
#define VFL_TYPE_VTX 3
#define VFL_TYPE_MAX 4
struct v4l2_ioctl_callbacks;
struct video_device;
struct v4l2_device;
/* Flag to mark the video_device struct as unregistered.
Drivers can set this flag if they want to block all future
device access. It is set by video_unregister_device. */
#define V4L2_FL_UNREGISTERED (0)
struct v4l2_file_operations {
struct module *owner;
ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
unsigned int (*poll) (struct file *, struct poll_table_struct *);
long (*ioctl) (struct file *, unsigned int, unsigned long);
long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
int (*mmap) (struct file *, struct vm_area_struct *);
int (*open) (struct file *);
int (*release) (struct file *);
};
/*
* Newer version of video_device, handled by videodev2.c
* This version moves redundant code from video device code to
* the common handler
*/
struct video_device
{
/* device ops */
const struct v4l2_file_operations *fops;
/* sysfs */
struct device dev; /* v4l device */
struct cdev *cdev; /* character device */
/* Set either parent or v4l2_dev if your driver uses v4l2_device */
struct device *parent; /* device parent */
struct v4l2_device *v4l2_dev; /* v4l2_device parent */
/* device info */
char name[32];
int vfl_type;
/* 'minor' is set to -1 if the registration failed */
int minor;
u16 num;
/* use bitops to set/clear/test flags */
unsigned long flags;
/* attribute to differentiate multiple indices on one physical device */
int index;
int debug; /* Activates debug level*/
/* Video standard vars */
v4l2_std_id tvnorms; /* Supported tv norms */
v4l2_std_id current_norm; /* Current tvnorm */
/* callbacks */
void (*release)(struct video_device *vdev);
/* ioctl callbacks */
const struct v4l2_ioctl_ops *ioctl_ops;
};
/* dev to video-device */
#define to_video_device(cd) container_of(cd, struct video_device, dev)
/* Register video devices. Note that if video_register_device fails,
the release() callback of the video_device structure is *not* called, so
the caller is responsible for freeing any data. Usually that means that
you call video_device_release() on failure.
Also note that vdev->minor is set to -1 if the registration failed. */
int __must_check video_register_device(struct video_device *vdev, int type, int nr);
int __must_check video_register_device_index(struct video_device *vdev,
int type, int nr, int index);
/* Unregister video devices. Will do nothing if vdev == NULL or
vdev->minor < 0. */
void video_unregister_device(struct video_device *vdev);
/* helper functions to alloc/release struct video_device, the
latter can also be used for video_device->release(). */
struct video_device * __must_check video_device_alloc(void);
/* this release function frees the vdev pointer */
void video_device_release(struct video_device *vdev);
/* this release function does nothing, use when the video_device is a
static global struct. Note that having a static video_device is
a dubious construction at best. */
void video_device_release_empty(struct video_device *vdev);
/* helper functions to access driver private data. */
static inline void *video_get_drvdata(struct video_device *vdev)
{
return dev_get_drvdata(&vdev->dev);
}
static inline void video_set_drvdata(struct video_device *vdev, void *data)
{
dev_set_drvdata(&vdev->dev, data);
}
struct video_device *video_devdata(struct file *file);
/* Combine video_get_drvdata and video_devdata as this is
used very often. */
static inline void *video_drvdata(struct file *file)
{
return video_get_drvdata(video_devdata(file));
}
static inline int video_is_unregistered(struct video_device *vdev)
{
return test_bit(V4L2_FL_UNREGISTERED, &vdev->flags);
}
#endif /* _V4L2_DEV_H */
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