libcamera: software_isp: Remove DebayerParams::kGain10

The constant is used in a single place internally and doesn't belong to
DebayerParams anymore.  Let's use 256 directly.

Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Andrei Konovalov <andrey.konovalov.ynk@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

include/libcamera/internal/software_isp/debayer_params.h

@@ -16,7 +16,6 @@
 namespace libcamera {
 
 struct DebayerParams {
-	static constexpr unsigned int kGain10 = 256;
 	static constexpr unsigned int kRGBLookupSize = 256;
 
 	using ColorLookupTable = std::array<uint8_t, kRGBLookupSize>;

src/ipa/simple/soft_simple.cpp

@@ -289,8 +289,7 @@ void IPASoftSimple::processStats(const ControlList &sensorControls)
 
 	for (unsigned int i = 0; i < DebayerParams::kRGBLookupSize; i++) {
 		constexpr unsigned int div =
-			DebayerParams::kRGBLookupSize * DebayerParams::kGain10 /
-			kGammaLookupSize;
+			DebayerParams::kRGBLookupSize * 256 / kGammaLookupSize;
 		unsigned int idx;
 
 		/* Apply gamma after gain! */

src/libcamera/software_isp/debayer.cpp

@@ -18,11 +18,6 @@ namespace libcamera {
  * \brief Struct to hold the debayer parameters.
  */
 
-/**
- * \var DebayerParams::kGain10
- * \brief const value for 1.0 gain
- */
-
 /**
  * \var DebayerParams::kRGBLookupSize
  * \brief Size of a color lookup table