/* * *	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> #include <media/media-entity.h> #define VIDEO_MAJOR	81 #define VFL_TYPE_GRABBER	0#define VFL_TYPE_VBI		1#define VFL_TYPE_RADIO		2#define VFL_TYPE_SUBDEV		3#define VFL_TYPE_MAX		4 struct v4l2_ioctl_callbacks;struct video_device;struct v4l2_device;struct v4l2_ctrl_handler; /* Flag to mark the video_device struct as registered.   Drivers can clear this flag if they want to block all future   device access. It is cleared by video_unregister_device. */#define V4L2_FL_REGISTERED	(0)/* file->private_data points to struct v4l2_fh */#define V4L2_FL_USES_V4L2_FH	(1)/* Use the prio field of v4l2_fh for core priority checking */#define V4L2_FL_USE_FH_PRIO	(2)/* If ioctl core locking is in use, then apply that also to all   file operations. Don't use this flag in new drivers! */#define V4L2_FL_LOCK_ALL_FOPS	(3) /* Priority helper functions */ struct v4l2_prio_state {	atomic_t prios[4];}; void v4l2_prio_init(struct v4l2_prio_state *global);int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,		     enum v4l2_priority new);void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);  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);#ifdef CONFIG_COMPAT	long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);#endif	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{#if defined(CONFIG_MEDIA_CONTROLLER)	struct media_entity entity;#endif	/* 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 */ 	/* Control handler associated with this device node. May be NULL. */	struct v4l2_ctrl_handler *ctrl_handler; 	/* Priority state. If NULL, then v4l2_dev->prio will be used. */	struct v4l2_prio_state *prio; 	/* 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; 	/* V4L2 file handles */	spinlock_t		fh_lock; /* Lock for all v4l2_fhs */	struct list_head	fh_list; /* List of struct v4l2_fh */ 	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;	DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE); 	/* serialization lock */	DECLARE_BITMAP(disable_locking, BASE_VIDIOC_PRIVATE);	struct mutex *lock;}; #define media_entity_to_video_device(__e) \	container_of(__e, struct video_device, entity)/* dev to video-device */#define to_video_device(cd) container_of(cd, struct video_device, dev) int __must_check __video_register_device(struct video_device *vdev, int type,		int nr, int warn_if_nr_in_use, struct module *owner); /* 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. */static inline int __must_check video_register_device(struct video_device *vdev,		int type, int nr){	return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);} /* Same as video_register_device, but no warning is issued if the desired   device node number was already in use. */static inline int __must_check video_register_device_no_warn(		struct video_device *vdev, int type, int nr){	return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);} /* Unregister video devices. Will do nothing if vdev == NULL or   video_is_registered() returns false. */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); /* returns true if cmd is a known V4L2 ioctl */bool v4l2_is_known_ioctl(unsigned int cmd); /* mark that this command shouldn't use core locking */static inline void v4l2_disable_ioctl_locking(struct video_device *vdev, unsigned int cmd){	if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)		set_bit(_IOC_NR(cmd), vdev->disable_locking);} /* Mark that this command isn't implemented. This must be called before   video_device_register. See also the comments in determine_valid_ioctls().   This function allows drivers to provide just one v4l2_ioctl_ops struct, but   disable ioctls based on the specific card that is actually found. */static inline void v4l2_disable_ioctl(struct video_device *vdev, unsigned int cmd){	if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)		set_bit(_IOC_NR(cmd), vdev->valid_ioctls);} /* 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 const char *video_device_node_name(struct video_device *vdev){	return dev_name(&vdev->dev);} static inline int video_is_registered(struct video_device *vdev){	return test_bit(V4L2_FL_REGISTERED, &vdev->flags);} #endif /* _V4L2_DEV_H */