[RFC 2/5] media: v4l2-ctrl: Document V4L2_CID_LOCATION

[Jacopo Mondi]

Add documentation for the V4L2_CID_LOCATION camera control. The newly
added read-only control reports the camera device mounting position.

Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
---
 .../media/uapi/v4l/ext-ctrls-camera.rst       | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst
index 51c1d5c9eb00..fc0a02eee6d4 100644
--- a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst
+++ b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst
@@ -510,6 +510,29 @@ enum v4l2_scene_mode -
     value down. A value of zero stops the motion if one is in progress
     and has no effect otherwise.

+``V4L2_CID_LOCATION (integer)``
+    This read-only control describes the camera location by reporting its
+    mounting position on the device where the camera is installed. This
+    control is particularly meaningful for devices which have a well defined
+    orientation, such as phones, laptops and portable devices as the camera
+    location is expressed as a position relative to the device intended
+    usage position. In example, a camera installed on the user-facing side
+    of a phone device is said to be installed in the ``V4L2_LOCATION_FRONT``
+    position.
+
+
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+
+    * - ``V4L2_LOCATION_FRONT``
+      - The camera device is located on the front side of the device.
+    * - ``V4L2_LOCATION_BACK``
+      - The camera device is located on the back side of the device.
+
+
+
 .. [#f1]
    This control may be changed to a menu control in the future, if more
    options are required.
--
2.22.0