[libcamera-devel] [PATCH v4 4/5] libcamera: controls: Improve documentation for ExposureTime and AnalogueGain

[David Plowman]

Setting these controls "fixes" them and the AE may not change them;
setting them back to zero returns them to the control of the AE
algorithm.

Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
---
 src/libcamera/control_ids.yaml | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
index a883e27e..fba1f545 100644
--- a/src/libcamera/control_ids.yaml
+++ b/src/libcamera/control_ids.yaml
@@ -125,8 +125,15 @@ controls:
         Exposure time (shutter speed) for the frame applied in the sensor
         device. This value is specified in micro-seconds.
 
+        Setting this value means that it is now fixed and the AE algorithm may
+        not change it. Setting it back to zero returns it to the control of the
+        AE algorithm.
+
         \sa AnalogueGain AeEnable
 
+        \todo Consider how setting the exposure time interacts with other AE
+              features, such as aperture, aperture/shutter priority modes etc.
+
   - AnalogueGain:
       type: float
       description: |
@@ -134,8 +141,15 @@ controls:
         The value of the control specifies the gain multiplier applied to all
         colour channels. This value cannot be lower than 1.0.
 
+        Setting this value means that it is now fixed and the AE algorithm may
+        not change it. Setting it back to zero returns it to the control of the
+        AE algorithm.
+
         \sa ExposureTime AeEnable
 
+        \todo Consider how setting the analogue gain interacts with other AE
+              features, such as aperture, aperture/shutter priority modes etc.
+
   - Brightness:
       type: float
       description: |
-- 
2.20.1