v4l2-dev.h 6.2 KB

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  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_MAX 4
  24. struct v4l2_ioctl_callbacks;
  25. struct video_device;
  26. struct v4l2_device;
  27. struct v4l2_ctrl_handler;
  28. /* Flag to mark the video_device struct as registered.
  29. Drivers can clear this flag if they want to block all future
  30. device access. It is cleared by video_unregister_device. */
  31. #define V4L2_FL_REGISTERED (0)
  32. /* file->private_data points to struct v4l2_fh */
  33. #define V4L2_FL_USES_V4L2_FH (1)
  34. /* Use the prio field of v4l2_fh for core priority checking */
  35. #define V4L2_FL_USE_FH_PRIO (2)
  36. /* Priority helper functions */
  37. struct v4l2_prio_state {
  38. atomic_t prios[4];
  39. };
  40. void v4l2_prio_init(struct v4l2_prio_state *global);
  41. int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
  42. enum v4l2_priority new);
  43. void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
  44. void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
  45. enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
  46. int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
  47. struct v4l2_file_operations {
  48. struct module *owner;
  49. ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
  50. ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
  51. unsigned int (*poll) (struct file *, struct poll_table_struct *);
  52. long (*ioctl) (struct file *, unsigned int, unsigned long);
  53. long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
  54. #ifdef CONFIG_COMPAT
  55. long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);
  56. #endif
  57. unsigned long (*get_unmapped_area) (struct file *, unsigned long,
  58. unsigned long, unsigned long, unsigned long);
  59. int (*mmap) (struct file *, struct vm_area_struct *);
  60. int (*open) (struct file *);
  61. int (*release) (struct file *);
  62. };
  63. /*
  64. * Newer version of video_device, handled by videodev2.c
  65. * This version moves redundant code from video device code to
  66. * the common handler
  67. */
  68. struct video_device
  69. {
  70. #if defined(CONFIG_MEDIA_CONTROLLER)
  71. struct media_entity entity;
  72. #endif
  73. /* device ops */
  74. const struct v4l2_file_operations *fops;
  75. /* sysfs */
  76. struct device dev; /* v4l device */
  77. struct cdev *cdev; /* character device */
  78. /* Set either parent or v4l2_dev if your driver uses v4l2_device */
  79. struct device *parent; /* device parent */
  80. struct v4l2_device *v4l2_dev; /* v4l2_device parent */
  81. /* Control handler associated with this device node. May be NULL. */
  82. struct v4l2_ctrl_handler *ctrl_handler;
  83. /* Priority state. If NULL, then v4l2_dev->prio will be used. */
  84. struct v4l2_prio_state *prio;
  85. /* device info */
  86. char name[32];
  87. int vfl_type;
  88. /* 'minor' is set to -1 if the registration failed */
  89. int minor;
  90. u16 num;
  91. /* use bitops to set/clear/test flags */
  92. unsigned long flags;
  93. /* attribute to differentiate multiple indices on one physical device */
  94. int index;
  95. /* V4L2 file handles */
  96. spinlock_t fh_lock; /* Lock for all v4l2_fhs */
  97. struct list_head fh_list; /* List of struct v4l2_fh */
  98. int debug; /* Activates debug level*/
  99. /* Video standard vars */
  100. v4l2_std_id tvnorms; /* Supported tv norms */
  101. v4l2_std_id current_norm; /* Current tvnorm */
  102. /* callbacks */
  103. void (*release)(struct video_device *vdev);
  104. /* ioctl callbacks */
  105. const struct v4l2_ioctl_ops *ioctl_ops;
  106. /* serialization lock */
  107. struct mutex *lock;
  108. };
  109. #define media_entity_to_video_device(__e) \
  110. container_of(__e, struct video_device, entity)
  111. /* dev to video-device */
  112. #define to_video_device(cd) container_of(cd, struct video_device, dev)
  113. int __must_check __video_register_device(struct video_device *vdev, int type,
  114. int nr, int warn_if_nr_in_use, struct module *owner);
  115. /* Register video devices. Note that if video_register_device fails,
  116. the release() callback of the video_device structure is *not* called, so
  117. the caller is responsible for freeing any data. Usually that means that
  118. you call video_device_release() on failure. */
  119. static inline int __must_check video_register_device(struct video_device *vdev,
  120. int type, int nr)
  121. {
  122. return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
  123. }
  124. /* Same as video_register_device, but no warning is issued if the desired
  125. device node number was already in use. */
  126. static inline int __must_check video_register_device_no_warn(
  127. struct video_device *vdev, int type, int nr)
  128. {
  129. return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
  130. }
  131. /* Unregister video devices. Will do nothing if vdev == NULL or
  132. video_is_registered() returns false. */
  133. void video_unregister_device(struct video_device *vdev);
  134. /* helper functions to alloc/release struct video_device, the
  135. latter can also be used for video_device->release(). */
  136. struct video_device * __must_check video_device_alloc(void);
  137. /* this release function frees the vdev pointer */
  138. void video_device_release(struct video_device *vdev);
  139. /* this release function does nothing, use when the video_device is a
  140. static global struct. Note that having a static video_device is
  141. a dubious construction at best. */
  142. void video_device_release_empty(struct video_device *vdev);
  143. /* helper functions to access driver private data. */
  144. static inline void *video_get_drvdata(struct video_device *vdev)
  145. {
  146. return dev_get_drvdata(&vdev->dev);
  147. }
  148. static inline void video_set_drvdata(struct video_device *vdev, void *data)
  149. {
  150. dev_set_drvdata(&vdev->dev, data);
  151. }
  152. struct video_device *video_devdata(struct file *file);
  153. /* Combine video_get_drvdata and video_devdata as this is
  154. used very often. */
  155. static inline void *video_drvdata(struct file *file)
  156. {
  157. return video_get_drvdata(video_devdata(file));
  158. }
  159. static inline const char *video_device_node_name(struct video_device *vdev)
  160. {
  161. return dev_name(&vdev->dev);
  162. }
  163. static inline int video_is_registered(struct video_device *vdev)
  164. {
  165. return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
  166. }
  167. #endif /* _V4L2_DEV_H */