[v11,02/19] libcamera: framebuffer_allocator: Make allocate() require count

23274 diff mbox series

diff --git a/Documentation/guides/application-developer.rst b/Documentation/guides/application-developer.rst
index f3798d17..dbd2bfc6 100644
--- a/Documentation/guides/application-developer.rst
+++ b/Documentation/guides/application-developer.rst
@@ -32,6 +32,7 @@  defined names and types without the need of prefixing them.
    #include <thread>
 
    #include <libcamera/libcamera.h>
+   #include <libcamera/property_ids.h>
 
    using namespace libcamera;
    using namespace std::chrono_literals;
@@ -276,7 +277,10 @@  Using the libcamera ``FrameBufferAllocator``
 
 Applications create a ``FrameBufferAllocator`` for a Camera and use it
 to allocate buffers for streams of a ``CameraConfiguration`` with the
-``allocate()`` function.
+``allocate()`` function. The number of buffers to be allocated needs to be
+specified, and should be at least equal to the value of the ``MinimumRequests``
+property in order for the pipeline to have enough requests to be able to
+capture without frame drops.
 
 The list of allocated buffers can be retrieved using the ``Stream`` instance
 as the parameter of the ``FrameBufferAllocator::buffers()`` function.
@@ -284,9 +288,10 @@  as the parameter of the ``FrameBufferAllocator::buffers()`` function.
 .. code:: cpp
 
    FrameBufferAllocator *allocator = new FrameBufferAllocator(camera);
+   unsigned int bufferCount = camera->properties().get(properties::MinimumRequests);
 
    for (StreamConfiguration &cfg : *config) {
-       int ret = allocator->allocate(cfg.stream());
+       int ret = allocator->allocate(cfg.stream(), bufferCount);
        if (ret < 0) {
            std::cerr << "Can't allocate buffers" << std::endl;
            return -ENOMEM;
diff --git a/Documentation/guides/pipeline-handler.rst b/Documentation/guides/pipeline-handler.rst
index 1079d998..2e9825dc 100644
--- a/Documentation/guides/pipeline-handler.rst
+++ b/Documentation/guides/pipeline-handler.rst
@@ -209,7 +209,7 @@  implementations for the overridden class members.
           Span<const StreamRole> roles) override;
           int configure(Camera *camera, CameraConfiguration *config) override;
 
-          int exportFrameBuffers(Camera *camera, Stream *stream,
+          int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
           std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
           int start(Camera *camera, const ControlList *controls) override;
@@ -1242,7 +1242,6 @@  handle this:
 
 .. code-block:: cpp
 
-   unsigned int count = stream->configuration().bufferCount;
    VividCameraData *data = cameraData(camera);
 
    return data->video_->exportBuffers(count, buffers);
diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h
index 94cee7bd..ce9d8812 100644
--- a/include/libcamera/camera.h
+++ b/include/libcamera/camera.h
@@ -163,7 +163,7 @@  private:
 	void requestComplete(Request *request);
 
 	friend class FrameBufferAllocator;
-	int exportFrameBuffers(Stream *stream,
+	int exportFrameBuffers(Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers);
 };
 
diff --git a/include/libcamera/framebuffer_allocator.h b/include/libcamera/framebuffer_allocator.h
index f3896bf2..1568c55d 100644
--- a/include/libcamera/framebuffer_allocator.h
+++ b/include/libcamera/framebuffer_allocator.h
@@ -25,7 +25,7 @@  public:
 	FrameBufferAllocator(std::shared_ptr<Camera> camera);
 	~FrameBufferAllocator();
 
-	int allocate(Stream *stream);
+	int allocate(Stream *stream, unsigned int count);
 	int free(Stream *stream);
 
 	bool allocated() const { return !buffers_.empty(); }
diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h
index 972a2fa6..0e9fe23e 100644
--- a/include/libcamera/internal/pipeline_handler.h
+++ b/include/libcamera/internal/pipeline_handler.h
@@ -48,7 +48,7 @@  public:
 									   Span<const StreamRole> roles) = 0;
 	virtual int configure(Camera *camera, CameraConfiguration *config) = 0;
 
-	virtual int exportFrameBuffers(Camera *camera, Stream *stream,
+	virtual int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 				       std::vector<std::unique_ptr<FrameBuffer>> *buffers) = 0;
 
 	virtual int start(Camera *camera, const ControlList *controls) = 0;
diff --git a/src/apps/cam/camera_session.cpp b/src/apps/cam/camera_session.cpp
index 97c1ae44..f50108f3 100644
--- a/src/apps/cam/camera_session.cpp
+++ b/src/apps/cam/camera_session.cpp
@@ -326,17 +326,22 @@  int CameraSession::startCapture()
 {
 	int ret;
 
-	/* Identify the stream with the least number of buffers. */
-	unsigned int nbuffers = UINT_MAX;
+	unsigned int nbuffers =
+		camera_->properties().get(properties::MinimumRequests).value();
+
 	for (StreamConfiguration &cfg : *config_) {
-		ret = allocator_->allocate(cfg.stream());
+		ret = allocator_->allocate(cfg.stream(), nbuffers);
 		if (ret < 0) {
 			std::cerr << "Can't allocate buffers" << std::endl;
 			return -ENOMEM;
 		}
 
 		unsigned int allocated = allocator_->buffers(cfg.stream()).size();
-		nbuffers = std::min(nbuffers, allocated);
+		if (allocated < nbuffers) {
+			std::cerr << "Unable to allocate enough buffers"
+				  << std::endl;
+			return -ENOMEM;
+		}
 	}
 
 	/*
diff --git a/src/apps/lc-compliance/helpers/capture.cpp b/src/apps/lc-compliance/helpers/capture.cpp
index 2a3fa3b6..690de005 100644
--- a/src/apps/lc-compliance/helpers/capture.cpp
+++ b/src/apps/lc-compliance/helpers/capture.cpp
@@ -120,7 +120,8 @@  void Capture::start()
 	assert(!allocator_.allocated());
 	assert(requests_.empty());
 
-	const auto bufferCount = config_->at(0).bufferCount;
+	unsigned int bufferCount =
+		camera_->properties().get(properties::MinimumRequests).value();
 
 	/* No point in testing less requests then the camera depth. */
 	if (queueLimit_ && *queueLimit_ < bufferCount) {
@@ -137,7 +138,7 @@  void Capture::start()
 	for (const auto &cfg : *config_) {
 		Stream *stream = cfg.stream();
 
-		int count = allocator_.allocate(stream);
+		int count = allocator_.allocate(stream, bufferCount);
 		ASSERT_GE(count, 0) << "Failed to allocate buffers";
 
 		const auto &buffers = allocator_.buffers(stream);
diff --git a/src/apps/qcam/main_window.cpp b/src/apps/qcam/main_window.cpp
index d2ccbd23..9a9b7fa9 100644
--- a/src/apps/qcam/main_window.cpp
+++ b/src/apps/qcam/main_window.cpp
@@ -12,6 +12,7 @@ 
 #include <string>
 
 #include <libcamera/camera_manager.h>
+#include <libcamera/property_ids.h>
 #include <libcamera/version.h>
 
 #include <QCoreApplication>
@@ -447,7 +448,14 @@  int MainWindow::startCapture()
 	for (StreamConfiguration &config : *config_) {
 		Stream *stream = config.stream();
 
-		ret = allocator_->allocate(stream);
+		/*
+		 * We hold on to a buffer for display, so need one extra from
+		 * the minimum required for capture.
+		 */
+		unsigned int bufferCount =
+			camera_->properties().get(properties::MinimumRequests).value() + 1;
+
+		ret = allocator_->allocate(stream, bufferCount);
 		if (ret < 0) {
 			qWarning() << "Failed to allocate capture buffers";
 			goto error;
diff --git a/src/gstreamer/gstlibcameraallocator.cpp b/src/gstreamer/gstlibcameraallocator.cpp
index d4492d99..0d8e4c40 100644
--- a/src/gstreamer/gstlibcameraallocator.cpp
+++ b/src/gstreamer/gstlibcameraallocator.cpp
@@ -12,6 +12,7 @@ 
 
 #include <libcamera/camera.h>
 #include <libcamera/framebuffer_allocator.h>
+#include <libcamera/property_ids.h>
 #include <libcamera/stream.h>
 
 #include "gstlibcamera-utils.h"
@@ -209,11 +210,14 @@  gst_libcamera_allocator_new(std::shared_ptr<Camera> camera,
 	if (ret)
 		return nullptr;
 
+	unsigned int bufferCount =
+		camera->properties().get(properties::MinimumRequests).value();
+
 	self->fb_allocator = new FrameBufferAllocator(camera);
 	for (StreamConfiguration &streamCfg : *config_) {
 		Stream *stream = streamCfg.stream();
 
-		ret = self->fb_allocator->allocate(stream);
+		ret = self->fb_allocator->allocate(stream, bufferCount);
 		if (ret <= 0)
 			return nullptr;
 
diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index c180a5fd..33e928b9 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -950,7 +950,7 @@  void Camera::disconnect()
 	disconnected.emit();
 }
 
-int Camera::exportFrameBuffers(Stream *stream,
+int Camera::exportFrameBuffers(Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	Private *const d = _d();
@@ -967,7 +967,7 @@  int Camera::exportFrameBuffers(Stream *stream,
 
 	return d->pipe_->invokeMethod(&PipelineHandler::exportFrameBuffers,
 				      ConnectionTypeBlocking, this, stream,
-				      buffers);
+				      count, buffers);
 }
 
 /**
diff --git a/src/libcamera/framebuffer_allocator.cpp b/src/libcamera/framebuffer_allocator.cpp
index 3d53bde2..c522f479 100644
--- a/src/libcamera/framebuffer_allocator.cpp
+++ b/src/libcamera/framebuffer_allocator.cpp
@@ -68,6 +68,7 @@  FrameBufferAllocator::~FrameBufferAllocator() = default;
 /**
  * \brief Allocate buffers for a configured stream
  * \param[in] stream The stream to allocate buffers for
+ * \param[in] count The number of buffers to allocate
  *
  * Allocate buffers suitable for capturing frames from the \a stream. The Camera
  * shall have been previously configured with Camera::configure() and shall be
@@ -76,6 +77,10 @@  FrameBufferAllocator::~FrameBufferAllocator() = default;
  * Upon successful allocation, the allocated buffers can be retrieved with the
  * buffers() function.
  *
+ * This function may allocate less buffers than requested, due to memory and
+ * other system constraints. The caller shall always check the return value to
+ * verify if the number of allocate buffers matches its needs.
+ *
  * \return The number of allocated buffers on success or a negative error code
  * otherwise
  * \retval -EACCES The camera is not in a state where buffers can be allocated
@@ -83,7 +88,7 @@  FrameBufferAllocator::~FrameBufferAllocator() = default;
  * not part of the active camera configuration
  * \retval -EBUSY Buffers are already allocated for the \a stream
  */
-int FrameBufferAllocator::allocate(Stream *stream)
+int FrameBufferAllocator::allocate(Stream *stream, unsigned int count)
 {
 	const auto &[it, inserted] = buffers_.try_emplace(stream);
 
@@ -92,7 +97,7 @@  int FrameBufferAllocator::allocate(Stream *stream)
 		return -EBUSY;
 	}
 
-	int ret = camera_->exportFrameBuffers(stream, &it->second);
+	int ret = camera_->exportFrameBuffers(stream, count, &it->second);
 	if (ret == -EINVAL)
 		LOG(Allocator, Error)
 			<< "Stream is not part of " << camera_->id()
diff --git a/src/libcamera/pipeline/imx8-isi/imx8-isi.cpp b/src/libcamera/pipeline/imx8-isi/imx8-isi.cpp
index 2b8a583e..21f44424 100644
--- a/src/libcamera/pipeline/imx8-isi/imx8-isi.cpp
+++ b/src/libcamera/pipeline/imx8-isi/imx8-isi.cpp
@@ -108,7 +108,7 @@  public:
 	generateConfiguration(Camera *camera, Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -908,10 +908,9 @@  int PipelineHandlerISI::configure(Camera *camera, CameraConfiguration *c)
 	return 0;
 }
 
-int PipelineHandlerISI::exportFrameBuffers(Camera *camera, Stream *stream,
+int PipelineHandlerISI::exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 					   std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
-	unsigned int count = stream->configuration().bufferCount;
 	Pipe *pipe = pipeFromStream(camera, stream);
 
 	return pipe->capture->exportBuffers(count, buffers);
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 356ca2e1..30b74d4e 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -139,7 +139,7 @@  public:
 								   Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -637,10 +637,10 @@  int PipelineHandlerIPU3::configure(Camera *camera, CameraConfiguration *c)
 }
 
 int PipelineHandlerIPU3::exportFrameBuffers(Camera *camera, Stream *stream,
+					    unsigned int count,
 					    std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	IPU3CameraData *data = cameraData(camera);
-	unsigned int count = stream->configuration().bufferCount;
 
 	if (stream == &data->outStream_)
 		return data->imgu_->output_->exportBuffers(count, buffers);
diff --git a/src/libcamera/pipeline/mali-c55/mali-c55.cpp b/src/libcamera/pipeline/mali-c55/mali-c55.cpp
index f0ab3d2e..9df1622e 100644
--- a/src/libcamera/pipeline/mali-c55/mali-c55.cpp
+++ b/src/libcamera/pipeline/mali-c55/mali-c55.cpp
@@ -608,6 +608,7 @@  public:
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
 	int exportFrameBuffers(Camera *camera, Stream *stream,
+			       unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 	int allocateBuffers(Camera *camera);
 	void freeBuffers(Camera *camera);
@@ -1087,10 +1088,10 @@  int PipelineHandlerMaliC55::configure(Camera *camera,
 }
 
 int PipelineHandlerMaliC55::exportFrameBuffers(Camera *camera, Stream *stream,
+					       unsigned int count,
 					       std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	MaliC55Pipe *pipe = pipeFromStream(cameraData(camera), stream);
-	unsigned int count = stream->configuration().bufferCount;
 
 	return pipe->cap->exportBuffers(count, buffers);
 }
diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index 5e3a4dba..4e8eff70 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -158,7 +158,7 @@  public:
 								   Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -953,10 +953,10 @@  int PipelineHandlerRkISP1::configure(Camera *camera, CameraConfiguration *c)
 }
 
 int PipelineHandlerRkISP1::exportFrameBuffers([[maybe_unused]] Camera *camera, Stream *stream,
+					      unsigned int count,
 					      std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	RkISP1CameraData *data = cameraData(camera);
-	unsigned int count = stream->configuration().bufferCount;
 
 	if (stream == &data->mainPathStream_) {
 		/*
diff --git a/src/libcamera/pipeline/rpi/common/pipeline_base.cpp b/src/libcamera/pipeline/rpi/common/pipeline_base.cpp
index ef51d530..dc1e0a2e 100644
--- a/src/libcamera/pipeline/rpi/common/pipeline_base.cpp
+++ b/src/libcamera/pipeline/rpi/common/pipeline_base.cpp
@@ -630,10 +630,10 @@  int PipelineHandlerBase::configure(Camera *camera, CameraConfiguration *config)
 }
 
 int PipelineHandlerBase::exportFrameBuffers([[maybe_unused]] Camera *camera, libcamera::Stream *stream,
+					    unsigned int count,
 					    std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	RPi::Stream *s = static_cast<RPi::Stream *>(stream);
-	unsigned int count = stream->configuration().bufferCount;
 	int ret = s->dev()->exportBuffers(count, buffers);
 
 	s->setExportedBuffers(buffers);
diff --git a/src/libcamera/pipeline/rpi/common/pipeline_base.h b/src/libcamera/pipeline/rpi/common/pipeline_base.h
index aae0c2f3..e73d6f18 100644
--- a/src/libcamera/pipeline/rpi/common/pipeline_base.h
+++ b/src/libcamera/pipeline/rpi/common/pipeline_base.h
@@ -218,7 +218,7 @@  public:
 	generateConfiguration(Camera *camera, Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, libcamera::Stream *stream,
+	int exportFrameBuffers(Camera *camera, libcamera::Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp
index 7abf0fc9..1e77ccdc 100644
--- a/src/libcamera/pipeline/simple/simple.cpp
+++ b/src/libcamera/pipeline/simple/simple.cpp
@@ -404,7 +404,7 @@  public:
 								   Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -1434,10 +1434,10 @@  int SimplePipelineHandler::configure(Camera *camera, CameraConfiguration *c)
 }
 
 int SimplePipelineHandler::exportFrameBuffers(Camera *camera, Stream *stream,
+					      unsigned int count,
 					      std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	SimpleCameraData *data = cameraData(camera);
-	unsigned int count = stream->configuration().bufferCount;
 
 	/*
 	 * Export buffers on the converter or capture video node, depending on
diff --git a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
index 31951a12..60c82364 100644
--- a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
@@ -87,7 +87,7 @@  public:
 								   Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -278,11 +278,12 @@  int PipelineHandlerUVC::configure(Camera *camera, CameraConfiguration *config)
 	return 0;
 }
 
-int PipelineHandlerUVC::exportFrameBuffers(Camera *camera, Stream *stream,
+int PipelineHandlerUVC::exportFrameBuffers(Camera *camera,
+					   [[maybe_unused]] Stream *stream,
+					   unsigned int count,
 					   std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	UVCCameraData *data = cameraData(camera);
-	unsigned int count = stream->configuration().bufferCount;
 
 	return data->video_->exportBuffers(count, buffers);
 }
diff --git a/src/libcamera/pipeline/vimc/vimc.cpp b/src/libcamera/pipeline/vimc/vimc.cpp
index 01685a64..8833647a 100644
--- a/src/libcamera/pipeline/vimc/vimc.cpp
+++ b/src/libcamera/pipeline/vimc/vimc.cpp
@@ -92,7 +92,7 @@  public:
 								   Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -343,11 +343,12 @@  int PipelineHandlerVimc::configure(Camera *camera, CameraConfiguration *config)
 	return 0;
 }
 
-int PipelineHandlerVimc::exportFrameBuffers(Camera *camera, Stream *stream,
+int PipelineHandlerVimc::exportFrameBuffers(Camera *camera,
+					    [[maybe_unused]] Stream *stream,
+					    unsigned int count,
 					    std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	VimcCameraData *data = cameraData(camera);
-	unsigned int count = stream->configuration().bufferCount;
 
 	return data->video_->exportBuffers(count, buffers);
 }
diff --git a/src/libcamera/pipeline/virtual/virtual.cpp b/src/libcamera/pipeline/virtual/virtual.cpp
index c33f1a5e..ad2bdb57 100644
--- a/src/libcamera/pipeline/virtual/virtual.cpp
+++ b/src/libcamera/pipeline/virtual/virtual.cpp
@@ -87,7 +87,7 @@  public:
 								   Span<const StreamRole> roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
-	int exportFrameBuffers(Camera *camera, Stream *stream,
+	int exportFrameBuffers(Camera *camera, Stream *stream, unsigned int count,
 			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;
 
 	int start(Camera *camera, const ControlList *controls) override;
@@ -269,6 +269,7 @@  int PipelineHandlerVirtual::configure(Camera *camera,
 
 int PipelineHandlerVirtual::exportFrameBuffers([[maybe_unused]] Camera *camera,
 					       Stream *stream,
+					       unsigned int count,
 					       std::vector<std::unique_ptr<FrameBuffer>> *buffers)
 {
 	if (!dmaBufAllocator_.isValid())
@@ -281,7 +282,7 @@  int PipelineHandlerVirtual::exportFrameBuffers([[maybe_unused]] Camera *camera,
 	for (size_t i = 0; i < info.numPlanes(); ++i)
 		planeSizes.push_back(info.planeSize(config.size, i));
 
-	return dmaBufAllocator_.exportBuffers(config.bufferCount, planeSizes, buffers);
+	return dmaBufAllocator_.exportBuffers(count, planeSizes, buffers);
 }
 
 int PipelineHandlerVirtual::start([[maybe_unused]] Camera *camera,
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index d84dff3c..3211256c 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -314,6 +314,7 @@  void PipelineHandler::unlockMediaDevices()
  * \brief Allocate and export buffers for \a stream
  * \param[in] camera The camera
  * \param[in] stream The stream to allocate buffers for
+ * \param[in] count The number of buffers to allocate
  * \param[out] buffers Array of buffers successfully allocated
  *
  * This function allocates buffers for the \a stream from the devices associated
diff --git a/src/py/libcamera/py_main.cpp b/src/py/libcamera/py_main.cpp
index 441a70ab..f75450ee 100644
--- a/src/py/libcamera/py_main.cpp
+++ b/src/py/libcamera/py_main.cpp
@@ -349,8 +349,8 @@  PYBIND11_MODULE(_libcamera, m)
 
 	pyFrameBufferAllocator
 		.def(py::init<PyCameraSmartPtr<Camera>>(), py::keep_alive<1, 2>())
-		.def("allocate", [](FrameBufferAllocator &self, Stream *stream) {
-			int ret = self.allocate(stream);
+		.def("allocate", [](FrameBufferAllocator &self, Stream *stream, unsigned int count) {
+			int ret = self.allocate(stream, count);
 			if (ret < 0)
 				throw std::system_error(-ret, std::generic_category(),
 							"Failed to allocate buffers");
diff --git a/src/v4l2/v4l2_camera.cpp b/src/v4l2/v4l2_camera.cpp
index 94d138cd..a4b0e562 100644
--- a/src/v4l2/v4l2_camera.cpp
+++ b/src/v4l2/v4l2_camera.cpp
@@ -162,7 +162,7 @@  int V4L2Camera::allocBuffers(unsigned int count)
 {
 	Stream *stream = config_->at(0).stream();
 
-	int ret = bufferAllocator_->allocate(stream);
+	int ret = bufferAllocator_->allocate(stream, count);
 	if (ret < 0)
 		return ret;
 
diff --git a/test/camera/camera_reconfigure.cpp b/test/camera/camera_reconfigure.cpp
index 06c87730..63a97863 100644
--- a/test/camera/camera_reconfigure.cpp
+++ b/test/camera/camera_reconfigure.cpp
@@ -17,6 +17,7 @@ 
 #include <libcamera/base/timer.h>
 
 #include <libcamera/framebuffer_allocator.h>
+#include <libcamera/property_ids.h>
 
 #include "camera_test.h"
 #include "test.h"
@@ -78,7 +79,9 @@  private:
 		 * same buffer allocation for each run.
 		 */
 		if (!allocated_) {
-			int ret = allocator_->allocate(stream);
+			unsigned int bufferCount =
+				camera_->properties().get(properties::MinimumRequests).value();
+			int ret = allocator_->allocate(stream, bufferCount);
 			if (ret < 0) {
 				cerr << "Failed to allocate buffers" << endl;
 				return TestFail;
diff --git a/test/camera/capture.cpp b/test/camera/capture.cpp
index 8766fb19..05f4a1e3 100644
--- a/test/camera/capture.cpp
+++ b/test/camera/capture.cpp
@@ -7,12 +7,13 @@ 
 
 #include <iostream>
 
-#include <libcamera/framebuffer_allocator.h>
-
 #include <libcamera/base/event_dispatcher.h>
 #include <libcamera/base/thread.h>
 #include <libcamera/base/timer.h>
 
+#include <libcamera/framebuffer_allocator.h>
+#include <libcamera/property_ids.h>
+
 #include "camera_test.h"
 #include "test.h"
 
@@ -101,8 +102,10 @@  protected:
 
 		Stream *stream = cfg.stream();
 
-		int ret = allocator_->allocate(stream);
-		if (ret < 0)
+		unsigned int bufferCount =
+			camera_->properties().get(properties::MinimumRequests).value();
+		int ret = allocator_->allocate(stream, bufferCount);
+		if (ret < static_cast<int>(bufferCount))
 			return TestFail;
 
 		for (const std::unique_ptr<FrameBuffer> &buffer : allocator_->buffers(stream)) {
diff --git a/test/camera/statemachine.cpp b/test/camera/statemachine.cpp
index 9c2b0c6a..a9ddb323 100644
--- a/test/camera/statemachine.cpp
+++ b/test/camera/statemachine.cpp
@@ -8,6 +8,7 @@ 
 #include <iostream>
 
 #include <libcamera/framebuffer_allocator.h>
+#include <libcamera/property_ids.h>
 
 #include "camera_test.h"
 #include "test.h"
@@ -120,7 +121,9 @@  protected:
 		/* Use internally allocated buffers. */
 		allocator_ = new FrameBufferAllocator(camera_);
 		Stream *stream = *camera_->streams().begin();
-		if (allocator_->allocate(stream) < 0)
+		unsigned int bufferCount =
+			camera_->properties().get(properties::MinimumRequests).value();
+		if (allocator_->allocate(stream, bufferCount) < 0)
 			return TestFail;
 
 		if (camera_->start())
diff --git a/test/fence.cpp b/test/fence.cpp
index 8095b228..eb6c8b54 100644
--- a/test/fence.cpp
+++ b/test/fence.cpp
@@ -18,6 +18,7 @@ 
 
 #include <libcamera/fence.h>
 #include <libcamera/framebuffer_allocator.h>
+#include <libcamera/property_ids.h>
 
 #include "camera_test.h"
 #include "test.h"
@@ -119,8 +120,11 @@  int FenceTest::init()
 	StreamConfiguration &cfg = config_->at(0);
 	stream_ = cfg.stream();
 
+	unsigned int bufferCount =
+		camera_->properties().get(properties::MinimumRequests).value();
+
 	allocator_ = std::make_unique<FrameBufferAllocator>(camera_);
-	if (allocator_->allocate(stream_) < 0)
+	if (allocator_->allocate(stream_, bufferCount) < 0)
 		return TestFail;
 
 	nbuffers_ = allocator_->buffers(stream_).size();
diff --git a/test/mapped-buffer.cpp b/test/mapped-buffer.cpp
index b4422f7d..1b98feea 100644
--- a/test/mapped-buffer.cpp
+++ b/test/mapped-buffer.cpp
@@ -8,6 +8,7 @@ 
 #include <iostream>
 
 #include <libcamera/framebuffer_allocator.h>
+#include <libcamera/property_ids.h>
 
 #include "libcamera/internal/mapped_framebuffer.h"
 
@@ -55,7 +56,9 @@  protected:
 
 		stream_ = cfg.stream();
 
-		int ret = allocator_->allocate(stream_);
+		unsigned int bufferCount =
+			camera_->properties().get(properties::MinimumRequests).value();
+		int ret = allocator_->allocate(stream_, bufferCount);
 		if (ret < 0)
 			return TestFail;