v4l2-fh.h 2.1 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465
  1. /*
  2. * v4l2-fh.h
  3. *
  4. * V4L2 file handle. Store per file handle data for the V4L2
  5. * framework. Using file handles is optional for the drivers.
  6. *
  7. * Copyright (C) 2009--2010 Nokia Corporation.
  8. *
  9. * Contact: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
  10. *
  11. * This program is free software; you can redistribute it and/or
  12. * modify it under the terms of the GNU General Public License
  13. * version 2 as published by the Free Software Foundation.
  14. *
  15. * This program is distributed in the hope that it will be useful, but
  16. * WITHOUT ANY WARRANTY; without even the implied warranty of
  17. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18. * General Public License for more details.
  19. *
  20. * You should have received a copy of the GNU General Public License
  21. * along with this program; if not, write to the Free Software
  22. * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  23. * 02110-1301 USA
  24. */
  25. #ifndef V4L2_FH_H
  26. #define V4L2_FH_H
  27. #include <linux/list.h>
  28. struct video_device;
  29. struct v4l2_events;
  30. struct v4l2_fh {
  31. struct list_head list;
  32. struct video_device *vdev;
  33. struct v4l2_events *events; /* events, pending and subscribed */
  34. };
  35. /*
  36. * Initialise the file handle. Parts of the V4L2 framework using the
  37. * file handles should be initialised in this function. Must be called
  38. * from driver's v4l2_file_operations->open() handler if the driver
  39. * uses v4l2_fh.
  40. */
  41. int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev);
  42. /*
  43. * Add the fh to the list of file handles on a video_device. The file
  44. * handle must be initialised first.
  45. */
  46. void v4l2_fh_add(struct v4l2_fh *fh);
  47. /*
  48. * Remove file handle from the list of file handles. Must be called in
  49. * v4l2_file_operations->release() handler if the driver uses v4l2_fh.
  50. */
  51. void v4l2_fh_del(struct v4l2_fh *fh);
  52. /*
  53. * Release resources related to a file handle. Parts of the V4L2
  54. * framework using the v4l2_fh must release their resources here, too.
  55. * Must be called in v4l2_file_operations->release() handler if the
  56. * driver uses v4l2_fh.
  57. */
  58. void v4l2_fh_exit(struct v4l2_fh *fh);
  59. #endif /* V4L2_EVENT_H */