[libcamera-devel] [PATCH v7 7/8] libcamera: ipu3: Connect viewfinder's BufferReady signal

[Jacopo Mondi]

The viewfinder and main output require identical logic for buffer and
request completion. Connect the viewfinder bufferReady signal to the slot
and handle requests for both main output and viewfinder there.

Update the slot logic to complete the request only when the last buffer
has completed, and make sure to complete requests in the same order they
have been queued to the pipeline handler.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/libcamera/pipeline/ipu3/ipu3.cpp | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 8fa59157532e..1964603c591f 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -747,6 +747,8 @@ int PipelineHandlerIPU3::registerCameras()
 					&IPU3CameraData::imguInputBufferReady);
 		data->imgu_->output_.dev->bufferReady.connect(data.get(),
 					&IPU3CameraData::imguOutputBufferReady);
+		data->imgu_->viewfinder_.dev->bufferReady.connect(data.get(),
+					&IPU3CameraData::imguOutputBufferReady);
 
 		/* Create and register the Camera instance. */
 		std::string cameraName = cio2->sensor_->entity()->name() + " "
@@ -792,10 +794,27 @@ void PipelineHandlerIPU3::IPU3CameraData::imguInputBufferReady(Buffer *buffer)
  */
 void PipelineHandlerIPU3::IPU3CameraData::imguOutputBufferReady(Buffer *buffer)
 {
-	Request *request = queuedRequests_.front();
+	Request *request = buffer->request();
+
+	if (!pipe_->completeBuffer(camera_, request, buffer))
+		/* Request not completed yet, return here. */
+		return;
 
-	pipe_->completeBuffer(camera_, request, buffer);
-	pipe_->completeRequest(camera_, request);
+	/*
+	 * Complete requests in queuing order: if some other request is
+	 * pending, postpone completion.
+	 */
+	if (request != queuedRequests_.front())
+		return;
+
+	/* Complete the pending requests in queuing order. */
+	while (1) {
+		request = queuedRequests_.front();
+		if (request->hasPendingBuffers())
+			break;
+
+		pipe_->completeRequest(camera_, request);
+	}
 }
 
 /**
-- 
2.21.0