/* * * 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 /* Is this a receiver, transmitter or mem-to-mem? */ /* Ignored for VFL_TYPE_SUBDEV. */ #define VFL_DIR_RX 0 #define VFL_DIR_TX 1 #define VFL_DIR_M2M 2 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) /* 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 */ struct v4l2_device *v4l2_dev; /* v4l2_device parent */ /* Only set parent if that can't be deduced from v4l2_dev */ struct device *dev_parent; /* device parent */ /* Control handler associated with this device node. May be NULL. */ struct v4l2_ctrl_handler *ctrl_handler; /* vb2_queue associated with this device node. May be NULL. */ struct vb2_queue *queue; /* Priority state. If NULL, then v4l2_dev->prio will be used. */ struct v4l2_prio_state *prio; /* device info */ char name[32]; int vfl_type; /* device type */ int vfl_dir; /* receiver, transmitter or m2m */ /* '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 */ /* 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 */