v4l2-dev.h 7.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237
  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. #include <linux/poll.h>
  12. #include <linux/fs.h>
  13. #include <linux/device.h>
  14. #include <linux/cdev.h>
  15. #include <linux/mutex.h>
  16. #include <linux/videodev2.h>
  17. #include <media/media-entity.h>
  18. #define VIDEO_MAJOR 81
  19. #define VFL_TYPE_GRABBER 0
  20. #define VFL_TYPE_VBI 1
  21. #define VFL_TYPE_RADIO 2
  22. #define VFL_TYPE_SUBDEV 3
  23. #define VFL_TYPE_SDR 4
  24. #define VFL_TYPE_MAX 5
  25. /* Is this a receiver, transmitter or mem-to-mem? */
  26. /* Ignored for VFL_TYPE_SUBDEV. */
  27. #define VFL_DIR_RX 0
  28. #define VFL_DIR_TX 1
  29. #define VFL_DIR_M2M 2
  30. struct v4l2_ioctl_callbacks;
  31. struct video_device;
  32. struct v4l2_device;
  33. struct v4l2_ctrl_handler;
  34. /* Flag to mark the video_device struct as registered.
  35. Drivers can clear this flag if they want to block all future
  36. device access. It is cleared by video_unregister_device. */
  37. #define V4L2_FL_REGISTERED (0)
  38. /* file->private_data points to struct v4l2_fh */
  39. #define V4L2_FL_USES_V4L2_FH (1)
  40. /* Priority helper functions */
  41. struct v4l2_prio_state {
  42. atomic_t prios[4];
  43. };
  44. void v4l2_prio_init(struct v4l2_prio_state *global);
  45. int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
  46. enum v4l2_priority new);
  47. void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
  48. void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
  49. enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
  50. int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
  51. struct v4l2_file_operations {
  52. struct module *owner;
  53. ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
  54. ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
  55. unsigned int (*poll) (struct file *, struct poll_table_struct *);
  56. long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
  57. #ifdef CONFIG_COMPAT
  58. long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);
  59. #endif
  60. unsigned long (*get_unmapped_area) (struct file *, unsigned long,
  61. unsigned long, unsigned long, unsigned long);
  62. int (*mmap) (struct file *, struct vm_area_struct *);
  63. int (*open) (struct file *);
  64. int (*release) (struct file *);
  65. };
  66. /*
  67. * Newer version of video_device, handled by videodev2.c
  68. * This version moves redundant code from video device code to
  69. * the common handler
  70. */
  71. struct video_device
  72. {
  73. #if defined(CONFIG_MEDIA_CONTROLLER)
  74. struct media_entity entity;
  75. #endif
  76. /* device ops */
  77. const struct v4l2_file_operations *fops;
  78. /* sysfs */
  79. struct device dev; /* v4l device */
  80. struct cdev *cdev; /* character device */
  81. struct v4l2_device *v4l2_dev; /* v4l2_device parent */
  82. /* Only set parent if that can't be deduced from v4l2_dev */
  83. struct device *dev_parent; /* device parent */
  84. /* Control handler associated with this device node. May be NULL. */
  85. struct v4l2_ctrl_handler *ctrl_handler;
  86. /* vb2_queue associated with this device node. May be NULL. */
  87. struct vb2_queue *queue;
  88. /* Priority state. If NULL, then v4l2_dev->prio will be used. */
  89. struct v4l2_prio_state *prio;
  90. /* device info */
  91. char name[32];
  92. int vfl_type; /* device type */
  93. int vfl_dir; /* receiver, transmitter or m2m */
  94. /* 'minor' is set to -1 if the registration failed */
  95. int minor;
  96. u16 num;
  97. /* use bitops to set/clear/test flags */
  98. unsigned long flags;
  99. /* attribute to differentiate multiple indices on one physical device */
  100. int index;
  101. /* V4L2 file handles */
  102. spinlock_t fh_lock; /* Lock for all v4l2_fhs */
  103. struct list_head fh_list; /* List of struct v4l2_fh */
  104. /* Internal device debug flags, not for use by drivers */
  105. int dev_debug;
  106. /* Video standard vars */
  107. v4l2_std_id tvnorms; /* Supported tv norms */
  108. /* callbacks */
  109. void (*release)(struct video_device *vdev);
  110. /* ioctl callbacks */
  111. const struct v4l2_ioctl_ops *ioctl_ops;
  112. DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
  113. /* serialization lock */
  114. DECLARE_BITMAP(disable_locking, BASE_VIDIOC_PRIVATE);
  115. struct mutex *lock;
  116. };
  117. #define media_entity_to_video_device(__e) \
  118. container_of(__e, struct video_device, entity)
  119. /* dev to video-device */
  120. #define to_video_device(cd) container_of(cd, struct video_device, dev)
  121. int __must_check __video_register_device(struct video_device *vdev, int type,
  122. int nr, int warn_if_nr_in_use, struct module *owner);
  123. /* Register video devices. Note that if video_register_device fails,
  124. the release() callback of the video_device structure is *not* called, so
  125. the caller is responsible for freeing any data. Usually that means that
  126. you call video_device_release() on failure. */
  127. static inline int __must_check video_register_device(struct video_device *vdev,
  128. int type, int nr)
  129. {
  130. return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
  131. }
  132. /* Same as video_register_device, but no warning is issued if the desired
  133. device node number was already in use. */
  134. static inline int __must_check video_register_device_no_warn(
  135. struct video_device *vdev, int type, int nr)
  136. {
  137. return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
  138. }
  139. /* Unregister video devices. Will do nothing if vdev == NULL or
  140. video_is_registered() returns false. */
  141. void video_unregister_device(struct video_device *vdev);
  142. /* helper functions to alloc/release struct video_device, the
  143. latter can also be used for video_device->release(). */
  144. struct video_device * __must_check video_device_alloc(void);
  145. /* this release function frees the vdev pointer */
  146. void video_device_release(struct video_device *vdev);
  147. /* this release function does nothing, use when the video_device is a
  148. static global struct. Note that having a static video_device is
  149. a dubious construction at best. */
  150. void video_device_release_empty(struct video_device *vdev);
  151. /* returns true if cmd is a known V4L2 ioctl */
  152. bool v4l2_is_known_ioctl(unsigned int cmd);
  153. /* mark that this command shouldn't use core locking */
  154. static inline void v4l2_disable_ioctl_locking(struct video_device *vdev, unsigned int cmd)
  155. {
  156. if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
  157. set_bit(_IOC_NR(cmd), vdev->disable_locking);
  158. }
  159. /* Mark that this command isn't implemented. This must be called before
  160. video_device_register. See also the comments in determine_valid_ioctls().
  161. This function allows drivers to provide just one v4l2_ioctl_ops struct, but
  162. disable ioctls based on the specific card that is actually found. */
  163. static inline void v4l2_disable_ioctl(struct video_device *vdev, unsigned int cmd)
  164. {
  165. if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
  166. set_bit(_IOC_NR(cmd), vdev->valid_ioctls);
  167. }
  168. /* helper functions to access driver private data. */
  169. static inline void *video_get_drvdata(struct video_device *vdev)
  170. {
  171. return dev_get_drvdata(&vdev->dev);
  172. }
  173. static inline void video_set_drvdata(struct video_device *vdev, void *data)
  174. {
  175. dev_set_drvdata(&vdev->dev, data);
  176. }
  177. struct video_device *video_devdata(struct file *file);
  178. /* Combine video_get_drvdata and video_devdata as this is
  179. used very often. */
  180. static inline void *video_drvdata(struct file *file)
  181. {
  182. return video_get_drvdata(video_devdata(file));
  183. }
  184. static inline const char *video_device_node_name(struct video_device *vdev)
  185. {
  186. return dev_name(&vdev->dev);
  187. }
  188. static inline int video_is_registered(struct video_device *vdev)
  189. {
  190. return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
  191. }
  192. #endif /* _V4L2_DEV_H */