/* * * 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); /* Same as video_register_device, but no warning is issued if the desired device node number was already in use. */ int __must_check video_register_device_no_warn(struct video_device *vdev, int type, int nr); /* 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 */