media: Documentation: Add ST VGXY61 driver documentation
Document V4L2_CID_HDR_MODE possible values for this sensor.
Signed-off-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
diff --git a/Documentation/userspace-api/media/drivers/st-vgxy61.rst b/Documentation/userspace-api/media/drivers/st-vgxy61.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+ST VGXY61 camera sensor driver
+==============================
+
+The ST VGXY61 driver implements the following controls:
+
+``V4L2_CID_HDR_SENSOR_MODE``
+-------------------------------
+ Change the sensor HDR mode. A HDR picture is obtained by merging two captures of the same scene
+ using two different exposure periods.
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 4
+
+ * - HDR linearize
+ - The merger outputs a long exposure capture as long as it is not saturated.
+ * - HDR substraction
+ - This involves subtracting the short exposure frame from the long exposure frame.
+ * - "No HDR"
+ - This mode is used for standard dynamic range (SDR) exposures.
