ipu3: Add a class AiqResultsRingBuffer to reserve AiqResults history

The AIQ algorithm expects the statstistics comes with the effective AiqResults
applied on the sensor, which may not always be the latest AiqResults,
since pipeline handler may delay setting the controls based on SOF.
Add a class to reserve the history of the AiqResults generated for previous
frames, so IPA can have a chance to look for the suitable one backwards.

In details, the patch adds following to AiqResult Class.
 - Make the parameters to setXXX() functions const.
 - Implement copy constructors
 - Implement a RingBuffer to maintain AiqResults History

Signed-off-by: Han-Lin Chen <hanlinchen@chromium.org>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 82 insertions, 8 deletions

diff --git a/aiq/aiq_results.cpp b/aiq/aiq_results.cpp
index f727f36..befcf7a 100644
--- a/aiq/aiq_results.cpp
+++ b/aiq/aiq_results.cpp
@@ -63,7 +63,34 @@ AiqResults::AiqResults()
 	sa_.channel_b = channelB_.data();
 }
 
-void AiqResults::setAe(ia_aiq_ae_results *ae)
+AiqResults::AiqResults(const AiqResults &other)
+	:AiqResults()
+{
+	setAe(&other.ae_);
+	setAf(&other.af_);
+	setAfBracket(&other.afBracket_);
+	setAwb(&other.awb_);
+	setGbce(&other.gbce_);
+	setDetectedSceneMode(other.detectedSceneMode_);
+	setPa(&other.pa_);
+	setSa(&other.sa_);
+}
+
+AiqResults& AiqResults::operator=(const AiqResults &other)
+{
+	setAe(&other.ae_);
+	setAf(&other.af_);
+	setAfBracket(&other.afBracket_);
+	setAwb(&other.awb_);
+	setGbce(&other.gbce_);
+	setDetectedSceneMode(other.detectedSceneMode_);
+	setPa(&other.pa_);
+	setSa(&other.sa_);
+
+	return *this;
+}
+
+void AiqResults::setAe(const ia_aiq_ae_results *ae)
 {
 	/* Todo: Potentially Requires copying
 	 *   ia_aiq_aperture_control *aperture_control;
@@ -121,7 +148,7 @@ void AiqResults::setAe(ia_aiq_ae_results *ae)
 	}
 }
 
-void AiqResults::setAf(ia_aiq_af_results *af)
+void AiqResults::setAf(const ia_aiq_af_results *af)
 {
 	ASSERT(af);
 
@@ -133,7 +160,7 @@ void AiqResults::setAf(ia_aiq_af_results *af)
 	af_.final_lens_position_reached = af->final_lens_position_reached;
 }
 
-void AiqResults::setAfBracket(ia_aiq_af_bracket_results *afBracket)
+void AiqResults::setAfBracket(const ia_aiq_af_bracket_results *afBracket)
 {
 	ASSERT(afBracket);
 
@@ -145,7 +172,7 @@ void AiqResults::setAfBracket(ia_aiq_af_bracket_results *afBracket)
 	afBracket_.lens_positions_bracketing = afBracket->lens_positions_bracketing;
 }
 
-void AiqResults::setAwb(ia_aiq_awb_results *awb)
+void AiqResults::setAwb(const ia_aiq_awb_results *awb)
 {
 	ASSERT(awb);
 
@@ -157,7 +184,7 @@ void AiqResults::setAwb(ia_aiq_awb_results *awb)
 	awb_.distance_from_convergence = awb->distance_from_convergence;
 }
 
-void AiqResults::setGbce(ia_aiq_gbce_results *gbce)
+void AiqResults::setGbce(const ia_aiq_gbce_results *gbce)
 {
 	ASSERT(gbce);
 
@@ -181,12 +208,12 @@ void AiqResults::setGbce(ia_aiq_gbce_results *gbce)
 	}
 }
 
-void AiqResults::setDetectedSceneMode(ia_aiq_scene_mode dsm)
+void AiqResults::setDetectedSceneMode(const ia_aiq_scene_mode dsm)
 {
 	detectedSceneMode_ = dsm;
 }
 
-void AiqResults::setPa(ia_aiq_pa_results *pa)
+void AiqResults::setPa(const ia_aiq_pa_results *pa)
 {
 	ASSERT(pa);
 
@@ -234,7 +261,7 @@ void AiqResults::setPa(ia_aiq_pa_results *pa)
 	pa_.brightness_level = pa->brightness_level;
 }
 
-void AiqResults::setSa(ia_aiq_sa_results *sa)
+void AiqResults::setSa(const ia_aiq_sa_results *sa)
 {
 	ASSERT(sa && sa->channel_r && sa->channel_gr &&
 	       sa->channel_gb && sa->channel_b);
@@ -275,6 +302,53 @@ void AiqResults::setSa(ia_aiq_sa_results *sa)
 	sa_.frame_params = sa->frame_params;
 }
 
+AiqResults& AiqResultsRingBuffer::operator[](unsigned int index)
+{
+	return std::array<AiqResults, bufferSize>::operator[](index % bufferSize);
+}
+
+const AiqResults& AiqResultsRingBuffer::operator[](unsigned int index) const
+{
+	return std::array<AiqResults, bufferSize>::operator[](index % bufferSize);
+}
+
+void AiqResultsRingBuffer::reset()
+{
+	start_ = end_ = size_ = 0;
+}
+
+void AiqResultsRingBuffer::extendOne()
+{
+	end_ = (end_ + 1) % bufferSize;
+	size_ = std::min(size_ + 1, bufferSize);
+	if (size_ == bufferSize) {
+		start_ = end_;
+	}
+}
+
+AiqResults& AiqResultsRingBuffer::latest()
+{
+	unsigned int i = (end_ + bufferSize - 1) % bufferSize;
+	return operator[](i);
+}
+
+AiqResults& AiqResultsRingBuffer::searchBackward(
+		const std::function<bool(AiqResults&)> pred, AiqResults& def)
+{
+	if (size_ == 0)
+		return def;
+
+	unsigned int i = (end_ + bufferSize - 1) % bufferSize;
+	while (i != start_) {
+		if (pred(operator[](i))) {
+			return operator[](i);
+		}
+		i = (i + bufferSize - 1) % bufferSize;
+	}
+
+	return def;
+}
+
 } /* namespace ipa::ipu3::aiq */
 
 } /* namespace libcamera */