libcamera: ipa: simple: Disable Ccm algorithm by default again

The default CCM in uncalibrated.yaml is just an identity transformation
and has been enabled by default only to always provide a correction
matrix to GPU ISP.  It slows down CPU ISP when CCM is not used.

Now, when a default correction matrix is always provided to GPU ISP, we
can disable the Ccm algorithm in uncalibrated.yaml again.  The check for
ccmEnabled in GPU ISP is no longer needed and it must be removed in
order not to fail when Ccm algorithm is not enabled.  ccmEnabled flag is
still needed in CPU ISP where the processing differs based on whether
CCM is present or not.

Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Robert Mader <robert.mader@collabora.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/ipa/simple/data/uncalibrated.yaml

@@ -8,12 +8,12 @@ algorithms:
   # Color correction matrices can be defined here. The CCM algorithm
   # has a significant performance impact, and should only be enabled
   # if tuned.
-  - Ccm:
-      ccms:
-        - ct: 6500
-          ccm: [ 1, 0, 0,
-                 0, 1, 0,
-                 0, 0, 1]
+  # - Ccm:
+  #     ccms:
+  #       - ct: 6500
+  #         ccm: [ 1, 0, 0,
+  #                0, 1, 0,
+  #                0, 0, 1]
   - Adjust:
   - Agc:
 ...

src/libcamera/software_isp/debayer_egl.cpp

@@ -288,7 +288,7 @@ unsigned int DebayerEGL::frameSize()
 
 int DebayerEGL::configure(const StreamConfiguration &inputCfg,
 			  const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfgs,
-			  bool ccmEnabled)
+			  [[maybe_unused]] bool ccmEnabled)
 {
 	if (getInputConfig(inputCfg.pixelFormat, inputConfig_) != 0)
 		return -EINVAL;
@@ -296,9 +296,6 @@ int DebayerEGL::configure(const StreamConfiguration &inputCfg,
 	if (stats_->configure(inputCfg) != 0)
 		return -EINVAL;
 
-	if (!ccmEnabled)
-		return -EINVAL;
-
 	const Size &stats_pattern_size = stats_->patternSize();
 	if (inputConfig_.patternSize.width != stats_pattern_size.width ||
 	    inputConfig_.patternSize.height != stats_pattern_size.height) {