1 /* 2 * 3 * V 4 L 2 D R I V E R H E L P E R A P I 4 * 5 * Moved from videodev2.h 6 * 7 * Some commonly needed functions for drivers (v4l2-common.o module) 8 */ 9 #ifndef _V4L2_DEV_H 10 #define _V4L2_DEV_H 11 12 #include <linux/poll.h> 13 #include <linux/fs.h> 14 #include <linux/device.h> 15 #include <linux/cdev.h> 16 #include <linux/mutex.h> 17 #include <linux/videodev2.h> 18 19 #define VIDEO_MAJOR 81 20 21 #define VFL_TYPE_GRABBER 0 22 #define VFL_TYPE_VBI 1 23 #define VFL_TYPE_RADIO 2 24 #define VFL_TYPE_VTX 3 25 #define VFL_TYPE_MAX 4 26 27 struct v4l2_ioctl_callbacks; 28 29 /* 30 * Newer version of video_device, handled by videodev2.c 31 * This version moves redundant code from video device code to 32 * the common handler 33 */ 34 35 struct video_device 36 { 37 /* device ops */ 38 const struct file_operations *fops; 39 40 /* sysfs */ 41 struct device dev; /* v4l device */ 42 struct cdev cdev; /* character device */ 43 void (*cdev_release)(struct kobject *kobj); 44 struct device *parent; /* device parent */ 45 46 /* device info */ 47 char name[32]; 48 int vfl_type; 49 int minor; 50 u16 num; 51 /* attribute to differentiate multiple indices on one physical device */ 52 int index; 53 54 int debug; /* Activates debug level*/ 55 56 /* Video standard vars */ 57 v4l2_std_id tvnorms; /* Supported tv norms */ 58 v4l2_std_id current_norm; /* Current tvnorm */ 59 60 /* callbacks */ 61 void (*release)(struct video_device *vfd); 62 63 /* ioctl callbacks */ 64 const struct v4l2_ioctl_ops *ioctl_ops; 65 }; 66 67 /* dev to video-device */ 68 #define to_video_device(cd) container_of(cd, struct video_device, dev) 69 70 /* Register and unregister devices. Note that if video_register_device fails, 71 the release() callback of the video_device structure is *not* called, so 72 the caller is responsible for freeing any data. Usually that means that 73 you call video_device_release() on failure. */ 74 int __must_check video_register_device(struct video_device *vfd, int type, int nr); 75 int __must_check video_register_device_index(struct video_device *vfd, 76 int type, int nr, int index); 77 void video_unregister_device(struct video_device *vfd); 78 79 /* helper functions to alloc/release struct video_device, the 80 latter can also be used for video_device->release(). */ 81 struct video_device * __must_check video_device_alloc(void); 82 83 /* this release function frees the vfd pointer */ 84 void video_device_release(struct video_device *vfd); 85 86 /* this release function does nothing, use when the video_device is a 87 static global struct. Note that having a static video_device is 88 a dubious construction at best. */ 89 void video_device_release_empty(struct video_device *vfd); 90 91 /* helper functions to access driver private data. */ 92 static inline void *video_get_drvdata(struct video_device *dev) 93 { 94 return dev_get_drvdata(&dev->dev); 95 } 96 97 static inline void video_set_drvdata(struct video_device *dev, void *data) 98 { 99 dev_set_drvdata(&dev->dev, data); 100 } 101 102 struct video_device *video_devdata(struct file *file); 103 104 /* Combine video_get_drvdata and video_devdata as this is 105 used very often. */ 106 static inline void *video_drvdata(struct file *file) 107 { 108 return video_get_drvdata(video_devdata(file)); 109 } 110 111 #endif /* _V4L2_DEV_H */ 112