[libcamera-devel] [PATCH 2/3] pipeline: ipa: raspberrypi: Correctly report available control limits

[Naushir Patuck]

The ipa currently advertises a static ControlInfoMap to specify the available
controls and their limits. Fix this limitation by having the IPA populate a new
ControlInfoMap with updated limits for ExposureTime, AnalogueGain, and
FrameDurationLimits controls based on the current sensor mode. This new
ControlInfoMap is then returned back to the pipeline handler and available to
the application after a successful Camera::Configure() call.

Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
---
 include/libcamera/ipa/raspberrypi.mojom       |  1 +
 src/ipa/raspberrypi/raspberrypi.cpp           | 24 ++++++++++++++++---
 .../pipeline/raspberrypi/raspberrypi.cpp      |  3 +++
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/include/libcamera/ipa/raspberrypi.mojom b/include/libcamera/ipa/raspberrypi.mojom
index 77f52c282b0f..c0de435b7b33 100644
--- a/include/libcamera/ipa/raspberrypi.mojom
+++ b/include/libcamera/ipa/raspberrypi.mojom
@@ -45,6 +45,7 @@ struct IPAConfig {
 
 struct IPAConfigResult {
        float modeSensitivity;
+       libcamera.ControlInfoMap controlInfo;
 };
 
 struct StartConfig {
diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
index 089528f5e126..295f6b735dc0 100644
--- a/src/ipa/raspberrypi/raspberrypi.cpp
+++ b/src/ipa/raspberrypi/raspberrypi.cpp
@@ -74,8 +74,6 @@ constexpr Duration controllerMinFrameDuration = 1.0s / 30.0;
 /* List of controls handled by the Raspberry Pi IPA */
 static const ControlInfoMap::Map ipaControls{
 	{ &controls::AeEnable, ControlInfo(false, true) },
-	{ &controls::ExposureTime, ControlInfo(0, 999999) },
-	{ &controls::AnalogueGain, ControlInfo(1.0f, 32.0f) },
 	{ &controls::AeMeteringMode, ControlInfo(controls::AeMeteringModeValues) },
 	{ &controls::AeConstraintMode, ControlInfo(controls::AeConstraintModeValues) },
 	{ &controls::AeExposureMode, ControlInfo(controls::AeExposureModeValues) },
@@ -89,7 +87,6 @@ static const ControlInfoMap::Map ipaControls{
 	{ &controls::Sharpness, ControlInfo(0.0f, 16.0f, 1.0f) },
 	{ &controls::ColourCorrectionMatrix, ControlInfo(-16.0f, 16.0f) },
 	{ &controls::ScalerCrop, ControlInfo(Rectangle{}, Rectangle(65535, 65535, 65535, 65535), Rectangle{}) },
-	{ &controls::FrameDurationLimits, ControlInfo(INT64_C(1000), INT64_C(1000000000)) },
 	{ &controls::draft::NoiseReductionMode, ControlInfo(controls::draft::NoiseReductionModeValues) }
 };
 
@@ -446,6 +443,27 @@ int IPARPi::configure(const IPACameraSensorInfo &sensorInfo,
 	ASSERT(controls);
 	*controls = std::move(ctrls);
 
+	/*
+	 * Apply the correct limits to the exposure, gain and frame duration controls
+	 * based on the current sensor mode.
+	 */
+	ControlInfoMap::Map ctrlMap = ipaControls;
+	const Duration minSensorFrameDuration = mode_.min_frame_length * mode_.line_length;
+	const Duration maxSensorFrameDuration = mode_.max_frame_length * mode_.line_length;
+	ctrlMap.emplace(&controls::FrameDurationLimits,
+			ControlInfo(static_cast<int64_t>(minSensorFrameDuration.get<std::micro>()),
+				    static_cast<int64_t>(maxSensorFrameDuration.get<std::micro>())));
+
+	ctrlMap.emplace(&controls::AnalogueGain,
+			ControlInfo(1.0f, static_cast<float>(helper_->Gain(maxSensorGainCode_))));
+
+	const uint32_t exposureMin = sensorCtrls_.at(V4L2_CID_EXPOSURE).min().get<int32_t>();
+	const uint32_t exposureMax = sensorCtrls_.at(V4L2_CID_EXPOSURE).max().get<int32_t>();
+	ctrlMap.emplace(&controls::ExposureTime,
+			ControlInfo(static_cast<int32_t>(helper_->Exposure(exposureMin).get<std::micro>()),
+				    static_cast<int32_t>(helper_->Exposure(exposureMax).get<std::micro>())));
+
+	result->controlInfo = ControlInfoMap(std::move(ctrlMap), controls::controls);
 	return 0;
 }
 
diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
index d980c1a71dd8..4596f2babcea 100644
--- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
+++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
@@ -940,6 +940,9 @@ int PipelineHandlerRPi::configure(Camera *camera, CameraConfiguration *config)
 	/* Store the mode sensitivity for the application. */
 	data->properties_.set(properties::SensorSensitivity, result.modeSensitivity);
 
+	/* Update the controls that the Raspberry Pi IPA can handle. */
+	data->controlInfo_ = result.controlInfo;
+
 	/* Setup the Video Mux/Bridge entities. */
 	for (auto &[device, link] : data->bridgeDevices_) {
 		/*
-- 
2.25.1