![Daniel Glöckner](/assets/img/avatar_default.png)
Shared memory mappings on nommu machines require a get_unmapped_area file operation that suggests an address for the mapping. This patch adds a way for v4l2 drivers to provide this callback. Signed-off-by: Daniel Glöckner <dg@emlix.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
148 lines
4.4 KiB
C
148 lines
4.4 KiB
C
/*
|
|
*
|
|
* 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);
|
|
unsigned long (*get_unmapped_area) (struct file *, unsigned long,
|
|
unsigned long, unsigned long, 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 */
|