[PATCH v4 02/11] media: v4l2-ctrl: Document V4L2_CID_CAMERA_SENSOR_LOCATION

[Jacopo Mondi <jacopo@jmondi.org>]

Add documentation for the V4L2_CID_CAMERA_SENSOR_LOCATION camera
control. The newly added read-only control reports the camera device
mounting position.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
---
 .../media/uapi/v4l/ext-ctrls-camera.rst       | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst
index 51c1d5c9eb00..b151c016256c 100644
--- a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst
+++ b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst
@@ -510,6 +510,38 @@ 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_CAMERA_SENSOR_LOCATION (integer)``
+    This read-only control describes the camera sensor location by reporting
+    its mounting position on the device where the camera is installed. The
+    control value is constant and not modifiable by software. This control is
+    particularly meaningful for devices which have a well defined orientation,
+    such as phones, laptops and portable devices since the camera location is
+    expressed as a position relative to the device's intended usage orientation.
+    For example, a camera sensor installed on the user-facing side of a phone,
+    a tablet or a laptop device is said to be installed in the
+    ``V4L2_LOCATION_FRONT`` location while camera sensors installed on the side
+    opposite the front one are said to be installed in the
+    ``V4L2_LOCATION_BACK`` location. Camera sensors not directly attached to
+    the device or attached in a way that allows them to move freely, such as
+    webcams and digital cameras, are said to have the ``V4L2_LOCATION_EXTERNAL``
+    location.
+
+
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+
+    * - ``V4L2_LOCATION_FRONT``
+      - The camera sensor is located on the front side of the device.
+    * - ``V4L2_LOCATION_BACK``
+      - The camera sensor is located on the back side of the device.
+    * - ``V4L2_LOCATION_EXTERNAL``
+      - The camera sensor is not directly attached to the device and is
+        freely movable.
+
+
+
 .. [#f1]
    This control may be changed to a menu control in the future, if more
    options are required.
-- 
2.23.0