[PATCH v1 11/11] ipa: rkisp1: blc: Add support for BLS in compand

[Laurent Pinchart]

From: Paul Elder <paul.elder at ideasonboard.com>

Add support for black level subtraction to use the BLS in the compand
block, for versions of the ISP (such as the one on the i.MX8MP) that
lack the dedicated BLS block but have BLS in the companding block.

Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 src/ipa/rkisp1/algorithms/blc.cpp | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/src/ipa/rkisp1/algorithms/blc.cpp b/src/ipa/rkisp1/algorithms/blc.cpp
index 464a0e066dd4..bc329ea035aa 100644
--- a/src/ipa/rkisp1/algorithms/blc.cpp
+++ b/src/ipa/rkisp1/algorithms/blc.cpp
@@ -110,7 +110,7 @@ int BlackLevelCorrection::init(IPAContext &context, const YamlObject &tuningData
 /**
  * \copydoc libcamera::ipa::Algorithm::prepare
  */
-void BlackLevelCorrection::prepare([[maybe_unused]] IPAContext &context,
+void BlackLevelCorrection::prepare(IPAContext &context,
 				   const uint32_t frame,
 				   [[maybe_unused]] IPAFrameContext &frameContext,
 				   RkISP1Params *params)
@@ -124,14 +124,28 @@ void BlackLevelCorrection::prepare([[maybe_unused]] IPAContext &context,
 	if (!tuningParameters_)
 		return;
 
-	auto config = params->block<Block::Bls>(RkISP1Params::State::Enable);
+	if (context.hw->compand) {
+		auto config = params->block<Block::CompandBls>(RkISP1Params::State::Enable);
 
-	config->enable_auto = 0;
-	/* The rkisp1 uses 12bit based black levels. Scale down accordingly. */
-	config->fixed_val.r = blackLevelRed_ >> 4;
-	config->fixed_val.gr = blackLevelGreenR_ >> 4;
-	config->fixed_val.gb = blackLevelGreenB_ >> 4;
-	config->fixed_val.b = blackLevelBlue_ >> 4;
+		/*
+		 * Scale up to the 20-bit black levels used by the companding
+		 * block.
+		 */
+		config->r = blackLevelRed_ << 4;
+		config->gr = blackLevelGreenR_ << 4;
+		config->gb = blackLevelGreenB_ << 4;
+		config->b = blackLevelBlue_ << 4;
+	} else {
+		auto config = params->block<Block::Bls>(RkISP1Params::State::Enable);
+
+		config->enable_auto = 0;
+
+		/* Scale down to the 12-bit black levels used by the BLS block. */
+		config->fixed_val.r = blackLevelRed_ >> 4;
+		config->fixed_val.gr = blackLevelGreenR_ >> 4;
+		config->fixed_val.gb = blackLevelGreenB_ >> 4;
+		config->fixed_val.b = blackLevelBlue_ >> 4;
+	}
 }
 
 /**
-- 
Regards,

Laurent Pinchart