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Diffstat (limited to 'Documentation/driver-api/media/v4l2-subdev.rst')
| -rw-r--r-- | Documentation/driver-api/media/v4l2-subdev.rst | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/driver-api/media/v4l2-subdev.rst b/Documentation/driver-api/media/v4l2-subdev.rst index a62e4aff31be..1db2ba27c54c 100644 --- a/Documentation/driver-api/media/v4l2-subdev.rst +++ b/Documentation/driver-api/media/v4l2-subdev.rst @@ -181,6 +181,8 @@ You can unregister a sub-device using: Afterwards the subdev module can be unloaded and :c:type:`sd <v4l2_subdev>`->dev == ``NULL``. +.. _media-registering-async-subdevs: + Registering asynchronous sub-devices ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -195,6 +197,11 @@ performed using the :c:func:`v4l2_async_unregister_subdev` call. Subdevices registered this way are stored in a global list of subdevices, ready to be picked up by bridge drivers. +Drivers must complete all initialization of the sub-device before +registering it using :c:func:`v4l2_async_register_subdev`, including +enabling runtime PM. This is because the sub-device becomes accessible +as soon as it gets registered. + Asynchronous sub-device notifiers ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |