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Diffstat (limited to 'Documentation/video4linux/v4l2-framework.txt')
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 1feecfc59c3d..eb8479565dc4 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -350,6 +350,24 @@ VIDIOC_TRY_EXT_CTRLS controls can be also be accessed through one (or several) V4L2 device nodes. +VIDIOC_DQEVENT +VIDIOC_SUBSCRIBE_EVENT +VIDIOC_UNSUBSCRIBE_EVENT + + The events ioctls are identical to the ones defined in V4L2. They + behave identically, with the only exception that they deal only with + events generated by the sub-device. Depending on the driver, those + events can also be reported by one (or several) V4L2 device nodes. + + Sub-device drivers that want to use events need to set the + V4L2_SUBDEV_USES_EVENTS v4l2_subdev::flags and initialize + v4l2_subdev::nevents to events queue depth before registering the + sub-device. After registration events can be queued as usual on the + v4l2_subdev::devnode device node. + + To properly support events, the poll() file operation is also + implemented. + I2C sub-device drivers ---------------------- |