ipa: raspberrypi: Generalise the contrast algorithm

Generalise the contrast algorithm code by removing any hard-coded
assumptions about the target hardware platform. Instead, the algorithm
code creates a generic Pwl that gets returned to the IPA, where it gets
converted to the bcm2835 hardware specific lookup table.

As a drive-by, remove an unused mutex.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 3 insertions, 8 deletions

diff --git a/src/ipa/raspberrypi/controller/contrast_status.h b/src/ipa/raspberrypi/controller/contrast_status.h
index ef2a7c68..fb9fe4ba 100644
--- a/src/ipa/raspberrypi/controller/contrast_status.h
+++ b/src/ipa/raspberrypi/controller/contrast_status.h
@@ -6,20 +6,15 @@
  */
 #pragma once
 
+#include "pwl.h"
+
 /*
  * The "contrast" algorithm creates a gamma curve, optionally doing a little bit
  * of contrast stretching based on the AGC histogram.
  */
 
-constexpr unsigned int ContrastNumPoints = 33;
-
-struct ContrastPoint {
-	uint16_t x;
-	uint16_t y;
-};
-
 struct ContrastStatus {
-	struct ContrastPoint points[ContrastNumPoints];
+	RPiController::Pwl gammaCurve;
 	double brightness;
 	double contrast;
 };