[libcamera-devel] [PATCH v2 09/12] libcamera: pipeline_handler: Prepare Request

[Jacopo Mondi]

Before queueing a request to the device, any synchronization fence from
the Request' framebuffers has to be waited on.

Connect the Request::Private::prepared signal to the function that
queues requests to the hardware and call Request::Private::prepare().

When the waiting request queue is inspected, verify the Request::Private
status to discern if a Request has failed preparing or it can be queued
to the hardware.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/libcamera/pipeline_handler.cpp | 32 +++++++++++++++++++++++++++---
 1 file changed, 29 insertions(+), 3 deletions(-)

diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 3b9145992c8f..82ef214d16f2 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -7,6 +7,7 @@
 
 #include "libcamera/internal/pipeline_handler.h"
 
+#include <chrono>
 #include <sys/sysmacros.h>
 
 #include <libcamera/base/log.h>
@@ -17,6 +18,7 @@
 #include <libcamera/framebuffer.h>
 
 #include "libcamera/internal/camera.h"
+#include "libcamera/internal/framebuffer.h"
 #include "libcamera/internal/device_enumerator.h"
 #include "libcamera/internal/media_device.h"
 #include "libcamera/internal/request.h"
@@ -36,6 +38,8 @@
  * the REGISTER_PIPELINE_HANDLER() macro.
  */
 
+using namespace std::chrono_literals;
+
 namespace libcamera {
 
 LOG_DEFINE_CATEGORY(Pipeline)
@@ -338,7 +342,14 @@ void PipelineHandler::queueRequest(Request *request)
 	LIBCAMERA_TRACEPOINT(request_queue, request);
 
 	waitingRequests_.push_back(request);
-	doQueueRequests();
+
+	request->_d()->prepared.connect(this, [this]() {
+						doQueueRequests();
+					});
+
+	Request::Private::Status status = request->_d()->prepare(300ms);
+	if (status == Request::Private::Status::Ready)
+		doQueueRequests();
 }
 
 /**
@@ -354,6 +365,12 @@ void PipelineHandler::doQueueRequest(Request *request)
 
 	request->_d()->sequence_ = data->requestSequence_++;
 
+	if (request->_d()->privateStatus() == Request::Private::Status::Failed) {
+		request->_d()->cancel();
+		completeRequest(request);
+		return;
+	}
+
 	int ret = queueRequestDevice(camera, request);
 	if (ret) {
 		request->_d()->cancel();
@@ -371,9 +388,18 @@ void PipelineHandler::doQueueRequests()
 			return;
 
 		Request *request = waitingRequests_.front();
-		waitingRequests_.pop_front();
+		Request::Private::Status status = request->_d()->privateStatus();
+
+		switch (status) {
+		case Request::Private::Status::Pending:
+			return;
 
-		doQueueRequest(request);
+		case Request::Private::Status::Failed:
+		case Request::Private::Status::Ready:
+			waitingRequests_.pop_front();
+			doQueueRequest(request);
+			break;
+		}
 	}
 }
 
-- 
2.33.1