ipa: raspberrypi: Add sensitivity field to camera mode

We use the CamHelper class to initialise it to the usual value of 1.

The CamHelper's GetModeSensitivity method can be redefined to
implement a different behaviour for sensors that require it.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>
Acked-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

4 files changed, 22 insertions, 0 deletions

diff --git a/src/ipa/raspberrypi/cam_helper.cpp b/src/ipa/raspberrypi/cam_helper.cpp
index 3c6afce7..8f64e014 100644
--- a/src/ipa/raspberrypi/cam_helper.cpp
+++ b/src/ipa/raspberrypi/cam_helper.cpp
@@ -129,6 +129,17 @@ bool CamHelper::SensorEmbeddedDataPresent() const
 	return false;
 }
 
+double CamHelper::GetModeSensitivity([[maybe_unused]] const CameraMode &mode) const
+{
+	/*
+	 * Most sensors have the same sensitivity in every mode, but this
+	 * method can be overridden for those that do not. Note that it is
+	 * called before mode_ is set, so it must return the sensitivity
+	 * of the mode that is passed in.
+	 */
+	return 1.0;
+}
+
 unsigned int CamHelper::HideFramesStartup() const
 {
 	/*
diff --git a/src/ipa/raspberrypi/cam_helper.hpp b/src/ipa/raspberrypi/cam_helper.hpp
index 200cc83f..0643b77a 100644
--- a/src/ipa/raspberrypi/cam_helper.hpp
+++ b/src/ipa/raspberrypi/cam_helper.hpp
@@ -41,6 +41,8 @@ namespace RPiController {
 //
 // A method to query if the sensor outputs embedded data that can be parsed.
 //
+// A method to return the sensitivity of a given camera mode.
+//
 // A parser to parse the embedded data buffers provided by some sensors (for
 // example, the imx219 does; the ov5647 doesn't). This allows us to know for
 // sure the exposure and gain of the frame we're looking at. CamHelper
@@ -84,6 +86,7 @@ public:
 	virtual void GetDelays(int &exposure_delay, int &gain_delay,
 			       int &vblank_delay) const;
 	virtual bool SensorEmbeddedDataPresent() const;
+	virtual double GetModeSensitivity(const CameraMode &mode) const;
 	virtual unsigned int HideFramesStartup() const;
 	virtual unsigned int HideFramesModeSwitch() const;
 	virtual unsigned int MistrustFramesStartup() const;
diff --git a/src/ipa/raspberrypi/controller/camera_mode.h b/src/ipa/raspberrypi/controller/camera_mode.h
index 65888230..e2b82828 100644
--- a/src/ipa/raspberrypi/controller/camera_mode.h
+++ b/src/ipa/raspberrypi/controller/camera_mode.h
@@ -41,6 +41,8 @@ struct CameraMode {
 	libcamera::Transform transform;
 	// minimum and maximum fame lengths in units of lines
 	uint32_t min_frame_length, max_frame_length;
+	// sensitivity of this mode
+	double sensitivity;
 };
 
 #ifdef __cplusplus
diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
index b08602f4..48e11c69 100644
--- a/src/ipa/raspberrypi/raspberrypi.cpp
+++ b/src/ipa/raspberrypi/raspberrypi.cpp
@@ -325,6 +325,12 @@ void IPARPi::setMode(const IPACameraSensorInfo &sensorInfo)
 	 */
 	mode_.min_frame_length = sensorInfo.minFrameLength;
 	mode_.max_frame_length = sensorInfo.maxFrameLength;
+
+	/*
+	 * Some sensors may have different sensitivities in different modes;
+	 * the CamHelper will know the correct value.
+	 */
+	mode_.sensitivity = helper_->GetModeSensitivity(mode_);
 }
 
 int IPARPi::configure(const IPACameraSensorInfo &sensorInfo,