[PATCH v3 2/6] libcamera: software_isp: Handle queued output buffers on stop

[Milan Zamazal]

When SoftwareIsp stops, input and output buffers queued to it may not
yet be fully processed.  They will be eventually returned but stop means
stop, there should be no processing related actions invoked afterwards.

Let's stop forwarding processed output buffers from the SoftwareIsp
slots once SoftwareIsp is stopped.  Let's track the queued output
buffers and mark those still pending as canceled in SoftwareIsp::stop
and return them to the pipeline handler.

Dealing with input buffers is addressed in a separate patch.

Signed-off-by: Milan Zamazal <mzamazal at redhat.com>
---
 .../internal/software_isp/software_isp.h      |  2 ++
 src/libcamera/software_isp/software_isp.cpp   | 23 ++++++++++++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/include/libcamera/internal/software_isp/software_isp.h b/include/libcamera/internal/software_isp/software_isp.h
index af0dcc24..5073ce7a 100644
--- a/include/libcamera/internal/software_isp/software_isp.h
+++ b/include/libcamera/internal/software_isp/software_isp.h
@@ -7,6 +7,7 @@
 
 #pragma once
 
+#include <deque>
 #include <functional>
 #include <initializer_list>
 #include <map>
@@ -101,6 +102,7 @@ private:
 
 	std::unique_ptr<ipa::soft::IPAProxySoft> ipa_;
 	bool running_;
+	std::deque<FrameBuffer *> queuedOutputBuffers_;
 };
 
 } /* namespace libcamera */
diff --git a/src/libcamera/software_isp/software_isp.cpp b/src/libcamera/software_isp/software_isp.cpp
index 1a39f4d8..140cddf3 100644
--- a/src/libcamera/software_isp/software_isp.cpp
+++ b/src/libcamera/software_isp/software_isp.cpp
@@ -13,10 +13,13 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <libcamera/base/log.h>
+
 #include <libcamera/controls.h>
 #include <libcamera/formats.h>
 #include <libcamera/stream.h>
 
+#include "libcamera/internal/framebuffer.h"
 #include "libcamera/internal/ipa_manager.h"
 #include "libcamera/internal/software_isp/debayer_params.h"
 
@@ -300,8 +303,11 @@ int SoftwareIsp::queueBuffers(uint32_t frame, FrameBuffer *input,
 			return -EINVAL;
 	}
 
-	for (auto iter = outputs.begin(); iter != outputs.end(); iter++)
-		process(frame, input, iter->second);
+	for (auto iter = outputs.begin(); iter != outputs.end(); iter++) {
+		FrameBuffer *const buffer = iter->second;
+		queuedOutputBuffers_.push_back(buffer);
+		process(frame, input, buffer);
+	}
 
 	return 0;
 }
@@ -331,6 +337,13 @@ void SoftwareIsp::stop()
 
 	running_ = false;
 	ipa_->stop();
+
+	for (auto buffer : queuedOutputBuffers_) {
+		FrameMetadata &metadata = buffer->_d()->metadata();
+		metadata.status = FrameMetadata::FrameCancelled;
+		outputBufferReady.emit(buffer);
+	}
+	queuedOutputBuffers_.clear();
 }
 
 /**
@@ -369,7 +382,11 @@ void SoftwareIsp::inputReady(FrameBuffer *input)
 
 void SoftwareIsp::outputReady(FrameBuffer *output)
 {
-	outputBufferReady.emit(output);
+	if (running_) {
+		ASSERT(queuedOutputBuffers_.front() == output);
+		queuedOutputBuffers_.pop_front();
+		outputBufferReady.emit(output);
+	}
 }
 
 } /* namespace libcamera */
-- 
2.48.1