libcamera: Replace utils::clamp() with std::clamp()

Now that libcamera uses C++17, the C++ standard library provides
std::clamp(). Drop our custom utils::clamp() function.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>

include/libcamera/internal/utils.h

@@ -65,13 +65,6 @@ unsigned int set_overlap(InputIt1 first1, InputIt1 last1,
 	return count;
 }
 
-/* C++11 doesn't provide std::clamp */
-template <typename T>
-const T& clamp(const T& v, const T& lo, const T& hi)
-{
-	return std::max(lo, std::min(v, hi));
-}
-
 using clock = std::chrono::steady_clock;
 using duration = std::chrono::steady_clock::duration;
 using time_point = std::chrono::steady_clock::time_point;

src/ipa/rkisp1/rkisp1.cpp

@@ -24,7 +24,6 @@
 #include <libipa/ipa_interface_wrapper.h>
 
 #include "libcamera/internal/log.h"
-#include "libcamera/internal/utils.h"
 
 namespace libcamera {
 
@@ -234,13 +233,13 @@ void IPARkISP1::updateStatistics(unsigned int frame,
 			double exposure;
 
 			exposure = factor * exposure_ * gain_ / minGain_;
-			exposure_ = utils::clamp<uint64_t>((uint64_t)exposure,
-							   minExposure_,
-							   maxExposure_);
+			exposure_ = std::clamp<uint64_t>((uint64_t)exposure,
+							 minExposure_,
+							 maxExposure_);
 
 			exposure = exposure / exposure_ * minGain_;
-			gain_ = utils::clamp<uint64_t>((uint64_t)exposure,
-						       minGain_, maxGain_);
+			gain_ = std::clamp<uint64_t>((uint64_t)exposure,
+						     minGain_, maxGain_);
 
 			setControls(frame + 1);
 		}

src/libcamera/pipeline/ipu3/imgu.cpp

@@ -7,6 +7,7 @@
 
 #include "imgu.h"
 
+#include <algorithm>
 #include <cmath>
 #include <limits>
 
@@ -129,7 +130,7 @@ void calculateBDSHeight(ImgUDevice::Pipe *pipe, const Size &iif, const Size &gdc
 	if (!isSameRatio(pipe->input, gdc)) {
 		float estIFHeight = (iif.width * gdc.height) /
 				    static_cast<float>(gdc.width);
-		estIFHeight = utils::clamp<float>(estIFHeight, minIFHeight, iif.height);
+		estIFHeight = std::clamp<float>(estIFHeight, minIFHeight, iif.height);
 		bool found = false;
 
 		ifHeight = utils::alignUp(estIFHeight, IF_ALIGN_H);

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -240,15 +240,15 @@ CameraConfiguration::Status IPU3CameraConfiguration::validate()
 			unsigned int limit;
 			limit = utils::alignDown(cio2Configuration_.size.width - 1,
 						 IMGU_OUTPUT_WIDTH_MARGIN);
-			cfg->size.width = utils::clamp(cfg->size.width,
-						       IMGU_OUTPUT_MIN_SIZE.width,
-						       limit);
+			cfg->size.width = std::clamp(cfg->size.width,
+						     IMGU_OUTPUT_MIN_SIZE.width,
+						     limit);
 
 			limit = utils::alignDown(cio2Configuration_.size.height - 1,
 						 IMGU_OUTPUT_HEIGHT_MARGIN);
-			cfg->size.height = utils::clamp(cfg->size.height,
-							IMGU_OUTPUT_MIN_SIZE.height,
-							limit);
+			cfg->size.height = std::clamp(cfg->size.height,
+						      IMGU_OUTPUT_MIN_SIZE.height,
+						      limit);
 
 			cfg->size.alignDownTo(IMGU_OUTPUT_WIDTH_ALIGN,
 					      IMGU_OUTPUT_HEIGHT_ALIGN);

src/libcamera/pipeline/vimc/vimc.cpp

@@ -360,7 +360,7 @@ int PipelineHandlerVimc::processControls(VimcCameraData *data, Request *request)
 		}
 
 		int32_t value = lroundf(it.second.get<float>() * 128 + offset);
-		controls.set(cid, utils::clamp(value, 0, 255));
+		controls.set(cid, std::clamp(value, 0, 255));
 	}
 
 	for (const auto &ctrl : controls)

src/libcamera/utils.cpp

@@ -146,14 +146,6 @@ std::string dirname(const std::string &path)
  * \return The number of elements in the intersection of the two ranges
  */
 
-/**
- * \fn libcamera::utils::clamp(const T& v, const T& lo, const T& hi)
- * \param[in] v The value to clamp
- * \param[in] lo The lower boundary to clamp v to
- * \param[in] hi The higher boundary to clamp v to
- * \return lo if v is less than lo, hi if v is greater than hi, otherwise v
- */
-
 /**
  * \typedef clock
  * \brief The libcamera clock (monotonic)