ipa: rkisp1: Add manual color gains

Add support for manually controlling the color gains on the rkisp1 IPA.
To that end, add and plumb the AwbEnable and ColourGains controls. As
per-frame controls aren't supported yet in the rkisp1 IPA, simply apply
and perform checks on the controls immediately.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/ipa/rkisp1/algorithms/awb.cpp

@@ -12,6 +12,7 @@
 
 #include <libcamera/base/log.h>
 
+#include <libcamera/control_ids.h>
 #include <libcamera/ipa/core_ipa_interface.h>
 
 /**
@@ -38,6 +39,7 @@ int Awb::configure(IPAContext &context,
 	context.frameContext.awb.gains.red = 1.0;
 	context.frameContext.awb.gains.blue = 1.0;
 	context.frameContext.awb.gains.green = 1.0;
+	context.frameContext.awb.autoEnabled = true;
 
 	/*
 	 * Define the measurement window for AWB as a centered rectangle
@@ -116,6 +118,34 @@ void Awb::prepare(IPAContext &context, rkisp1_params_cfg *params)
 	params->module_ens |= RKISP1_CIF_ISP_MODULE_AWB;
 }
 
+/**
+ * \copydoc libcamera::ipa::Algorithm::queueRequest
+ */
+void Awb::queueRequest(IPAContext &context,
+		       [[maybe_unused]] const uint32_t frame,
+		       const ControlList &controls)
+{
+	auto &awb = context.frameContext.awb;
+
+	const auto &awbEnable = controls.get(controls::AwbEnable);
+	if (awbEnable && *awbEnable != awb.autoEnabled) {
+		awb.autoEnabled = *awbEnable;
+
+		LOG(RkISP1Awb, Debug)
+			<< (*awbEnable ? "Enabling" : "Disabling") << " AWB";
+	}
+
+	const auto &colourGains = controls.get(controls::ColourGains);
+	if (colourGains && !awb.autoEnabled) {
+		awb.gains.red = (*colourGains)[0];
+		awb.gains.blue = (*colourGains)[1];
+
+		LOG(RkISP1Awb, Debug)
+			<< "Set colour gains to red: " << awb.gains.red
+			<< ", blue: " << awb.gains.blue;
+	}
+}
+
 /**
  * \copydoc libcamera::ipa::Algorithm::process
  */
@@ -164,8 +194,10 @@ void Awb::process([[maybe_unused]] IPAContext &context,
 	 * Gain values are unsigned integer value, range 0 to 4 with 8 bit
 	 * fractional part.
 	 */
-	frameContext.awb.gains.red = std::clamp(redGain, 0.0, 1023.0 / 256);
+	if (frameContext.awb.autoEnabled) {
-	frameContext.awb.gains.blue = std::clamp(blueGain, 0.0, 1023.0 / 256);
+		frameContext.awb.gains.red = std::clamp(redGain, 0.0, 1023.0 / 256);
+		frameContext.awb.gains.blue = std::clamp(blueGain, 0.0, 1023.0 / 256);
+	}
 	/* Hardcode the green gain to 1.0. */
 	frameContext.awb.gains.green = 1.0;
 

src/ipa/rkisp1/algorithms/awb.h

@@ -21,6 +21,8 @@ public:
 
 	int configure(IPAContext &context, const IPACameraSensorInfo &configInfo) override;
 	void prepare(IPAContext &context, rkisp1_params_cfg *params) override;
+	void queueRequest(IPAContext &context, const uint32_t frame,
+			  const ControlList &controls) override;
 	void process(IPAContext &context, IPAFrameContext *frameCtx,
 		     const rkisp1_stat_buffer *stats) override;
 

src/ipa/rkisp1/ipa_context.cpp

@@ -134,6 +134,9 @@ namespace libcamera::ipa::rkisp1 {
  *
  * \var IPAFrameContext::awb.temperatureK
  * \brief Estimated color temperature
+ *
+ * \var IPAFrameContext::awb.autoEnabled
+ * \brief Whether the Auto White Balance algorithm is enabled
  */
 
 /**

src/ipa/rkisp1/ipa_context.h

@@ -55,6 +55,7 @@ struct IPAFrameContext {
 		} gains;
 
 		double temperatureK;
+		bool autoEnabled;
 	} awb;
 
 	struct {

src/ipa/rkisp1/rkisp1.cpp

@@ -92,6 +92,8 @@ namespace {
 /* List of controls handled by the RkISP1 IPA */
 const ControlInfoMap::Map rkisp1Controls{
 	{ &controls::AeEnable, ControlInfo(false, true) },
+	{ &controls::AwbEnable, ControlInfo(false, true) },
+	{ &controls::ColourGains, ControlInfo(0.0f, 3.996f, 1.0f) },
 	{ &controls::Brightness, ControlInfo(-1.0f, 0.993f) },
 	{ &controls::Contrast, ControlInfo(0.0f, 1.993f) },
 	{ &controls::Saturation, ControlInfo(0.0f, 1.993f) },