driver-api/media/v4l2-dev.rst

7 :c:type:`video_device` struct (``v4l2-dev.h``). This struct can either be
14 	struct video_device *vdev = video_device_alloc();
26 	struct video_device *vdev = &my_vdev->vdev;
40 You should also set these fields of :c:type:`video_device`:
42 - :c:type:`video_device`->v4l2_dev: must be set to the :c:type:`v4l2_device`
45 - :c:type:`video_device`->name: set to something descriptive and unique.
47 - :c:type:`video_device`->vfl_dir: set this to ``VFL_DIR_RX`` for capture
51 - :c:type:`video_device`->fops: set to the :c:type:`v4l2_file_operations`
54 - :c:type:`video_device`->ioctl_ops: if you use the :c:type:`v4l2_ioctl_ops`
57   :c:type:`v4l2_ioctl_ops` struct. The :c:type:`video_device`->vfl_type and
58   :c:type:`video_device`->vfl_dir fields are used to disable ops that do not
64 - :c:type:`video_device`->lock: leave to ``NULL`` if you want to do all the
66   ``mutex_lock`` and before the :c:type:`video_device`->unlocked_ioctl
70 - :c:type:`video_device`->queue: a pointer to the struct vb2_queue
82 - :c:type:`video_device`->prio: keeps track of the priorities. Used to
89 - :c:type:`video_device`->dev_parent: you only set this if v4l2_device was
98   struct video_device is initialized you **do** know which parent
102 :c:type:`video_device`->unlocked_ioctl to :c:func:`video_ioctl2` in your
110 	(:c:type:`vdev <video_device>`, cmd).
121 :c:type:`media_entity` struct embedded in the :c:type:`video_device` struct
141 lock field in struct video_device, which is a pointer to a mutex.
146 is a second lock that you can set: :c:type:`video_device`->queue->lock. If
147 set, then this lock will be used instead of :c:type:`video_device`->lock
166 :c:type:`video_device` before calling v4l2_device_disconnect. If you are also
167 using :c:type:`video_device`->queue->lock, then you have to first lock
168 :c:type:`video_device`->queue->lock followed by :c:type:`video_device`->lock.
231 'name' attribute is the 'name' field of the video_device struct. The
244 - :c:type:`video_device`->vfl_type: the device type passed to
246 - :c:type:`video_device`->minor: the assigned device minor number.
247 - :c:type:`video_device`->num: the device node number (i.e. the X in
249 - :c:type:`video_device`->index: the device index number.
252 :c:func:`video_device_release` to free the allocated :c:type:`video_device`
253 struct, or free your own struct if the :c:type:`video_device` was embedded in
294 	(:c:type:`vdev <video_device>`);
321 - file and :c:type:`video_device` private data
323 You can set/get driver private data in the video_device struct using:
326 	(:c:type:`vdev <video_device>`);
329 	(:c:type:`vdev <video_device>`);
339 returns the video_device belonging to the file struct.
347 You can go from a :c:type:`video_device` struct to the v4l2_device struct using:
355 The :c:type:`video_device` node kernel name can be retrieved using:
358 	(:c:type:`vdev <video_device>`);
361 should be used where possible instead of accessing the video_device::num and
362 video_device::minor fields.
364 video_device functions and data structures