[media] V4L: Add camera exposure metering control

The V4L2_CID_EXPOSURE_METERING control allows to determine
a method used by the camera for measuring the amount of light
available for automatic exposure.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml
index 8fccfe1b2058..e8c63e04741f 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -2864,6 +2864,35 @@ exposure time and/or aperture.</para></entry>
           </row>
           <row><entry></entry></row>
 
+          <row id="v4l2-exposure-metering">
+            <entry spanname="id"><constant>V4L2_CID_EXPOSURE_METERING</constant>&nbsp;</entry>
+            <entry>enum&nbsp;v4l2_exposure_metering</entry>
+          </row><row><entry spanname="descr">Determines how the camera measures
+the amount of light available for the frame exposure. Possible values are:</entry>
+          </row>
+          <row>
+            <entrytbl spanname="descr" cols="2">
+              <tbody valign="top">
+                <row>
+                  <entry><constant>V4L2_EXPOSURE_METERING_AVERAGE</constant>&nbsp;</entry>
+                  <entry>Use the light information coming from the entire frame
+and average giving no weighting to any particular portion of the metered area.
+                  </entry>
+                </row>
+                <row>
+                  <entry><constant>V4L2_EXPOSURE_METERING_CENTER_WEIGHTED</constant>&nbsp;</entry>
+                  <entry>Average the light information coming from the entire frame
+giving priority to the center of the metered area.</entry>
+                </row>
+                <row>
+                  <entry><constant>V4L2_EXPOSURE_METERING_SPOT</constant>&nbsp;</entry>
+                  <entry>Measure only very small area at the center of the frame.</entry>
+                </row>
+              </tbody>
+            </entrytbl>
+          </row>
+          <row><entry></entry></row>
+
           <row>
             <entry spanname="id"><constant>V4L2_CID_PAN_RELATIVE</constant>&nbsp;</entry>
             <entry>integer</entry>