[libcamera-devel] [PATCH 4/6] test: v4l2_videodevice: Add M2M device test

[Laurent Pinchart]

Hi Kieran,

Thank you for the patch.

On Thu, Aug 08, 2019 at 04:12:19PM +0100, Kieran Bingham wrote:
> The V4L2M2MDevice requires two pipelines to be configured. This makes it unsuitable
> to reuse the existing V4L2DeviceTest test library in it's current form.

s/it's/its/

Commit messages should wrap at 72 columns.

> Implement a full test to run the two M2M pipelines through VIM2M.

Lovely, another driver for our test suite :-)

> 
> Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> ---
>  test/v4l2_videodevice/meson.build        |   1 +
>  test/v4l2_videodevice/v4l2_m2mdevice.cpp | 210 +++++++++++++++++++++++
>  2 files changed, 211 insertions(+)
>  create mode 100644 test/v4l2_videodevice/v4l2_m2mdevice.cpp
> 
> diff --git a/test/v4l2_videodevice/meson.build b/test/v4l2_videodevice/meson.build
> index 76be5e142bb6..ad41898b5f8b 100644
> --- a/test/v4l2_videodevice/meson.build
> +++ b/test/v4l2_videodevice/meson.build
> @@ -7,6 +7,7 @@ v4l2_videodevice_tests = [
>      [ 'stream_on_off',      'stream_on_off.cpp' ],
>      [ 'capture_async',      'capture_async.cpp' ],
>      [ 'buffer_sharing',     'buffer_sharing.cpp' ],
> +    [ 'v4l2_m2mdevice',     'v4l2_m2mdevice.cpp' ],
>  ]
>  
>  foreach t : v4l2_videodevice_tests
> diff --git a/test/v4l2_videodevice/v4l2_m2mdevice.cpp b/test/v4l2_videodevice/v4l2_m2mdevice.cpp
> new file mode 100644
> index 000000000000..7a730f695ab7
> --- /dev/null
> +++ b/test/v4l2_videodevice/v4l2_m2mdevice.cpp
> @@ -0,0 +1,210 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright (C) 2019, Google Inc.
> + *
> + * libcamera V4L2 API tests

Copy & paste ?

> + */
> +
> +#include <libcamera/buffer.h>
> +#include <libcamera/camera_manager.h>
> +#include <libcamera/event_dispatcher.h>
> +#include <libcamera/timer.h>
> +
> +#include <iostream>
> +#include <memory>
> +
> +#include "device_enumerator.h"
> +#include "media_device.h"
> +#include "v4l2_videodevice.h"
> +
> +#include "test.h"
> +
> +using namespace std;
> +using namespace libcamera;
> +
> +class V4L2M2MDeviceTest : public Test
> +{
> +public:
> +	V4L2M2MDeviceTest()
> +		: vim2m_(nullptr), outputFrames_(0), captureFrames_(0)
> +	{
> +	}
> +
> +	void outputBufferComplete(Buffer *buffer)
> +	{
> +		std::cout << "Received output buffer " << buffer->index()
> +			  << std::endl;

My preference goes with using the std:: prefix explicitly like here, in
which case you should use it everywhere and drop the using namespace std
statement. The alternative is to remove it everywhere.

> +
> +		outputFrames_++;
> +
> +		/* Requeue the buffer for further use. */
> +		vim2m_->output()->queueBuffer(buffer);
> +	}
> +
> +	void receiveCaptureBuffer(Buffer *buffer)
> +	{
> +		std::cout << "Received capture buffer " << buffer->index()
> +			  << std::endl;
> +
> +		captureFrames_++;
> +
> +		/* Requeue the buffer for further use. */
> +		vim2m_->capture()->queueBuffer(buffer);
> +	}
> +
> +protected:
> +	int init()
> +	{
> +		enumerator_ = DeviceEnumerator::create();
> +		if (!enumerator_) {
> +			cerr << "Failed to create device enumerator" << endl;
> +			return TestFail;
> +		}
> +
> +		if (enumerator_->enumerate()) {
> +			cerr << "Failed to enumerate media devices" << endl;
> +			return TestFail;
> +		}
> +
> +		DeviceMatch dm("vim2m");
> +		dm.add("vim2m-source");
> +		dm.add("vim2m-sink");
> +
> +		media_ = enumerator_->search(dm);
> +		if (!media_) {
> +			cerr << "Failed to match device" << endl;

Maybe "No vim2m device found" ?

> +			return TestSkip;
> +		}
> +
> +		MediaEntity *entity = media_->getEntityByName("vim2m-source");
> +		if (!entity) {
> +			cerr << "Failed to get device entity" << endl;

This can't happen due to the dm.add().

> +			return TestSkip;
> +		}
> +

I would move the rest of the code to the run() function as it tests the
V4L2M2MDevice API.

> +		vim2m_ = new V4L2M2MDevice(entity->deviceNode());
> +		if (vim2m_->status())

You should add a message here (and below). It's difficult to debug test
failures when no message is printed.

> +			return TestFail;
> +
> +		V4L2DeviceFormat format = {};
> +		if (vim2m_->capture()->getFormat(&format))
> +			return TestFail;
> +
> +		format.size.width = 640;
> +		format.size.height = 480;
> +
> +		if (vim2m_->capture()->setFormat(&format))
> +			return TestFail;
> +
> +		if (vim2m_->output()->setFormat(&format))
> +			return TestFail;
> +
> +		cerr << "Initialised M2M ..." << endl;

I'd drop this line.

> +
> +		return TestPass;
> +	}
> +
> +	int run()
> +	{
> +		const unsigned int bufferCount = 8;

s/const/constexpr/

Would 4 buffers be enough ?

> +
> +		EventDispatcher *dispatcher = CameraManager::instance()->eventDispatcher();
> +		Timer timeout;
> +		int ret;
> +
> +		capturePool_.createBuffers(bufferCount);
> +		outputPool_.createBuffers(bufferCount);
> +
> +		ret = vim2m_->capture()->exportBuffers(&capturePool_);
> +		if (ret) {
> +			cerr << "Failed to export Capture Buffers" << endl;
> +			return TestFail;
> +		}
> +
> +		ret = vim2m_->output()->exportBuffers(&outputPool_);
> +		if (ret) {
> +			cerr << "Failed to export Output Buffers" << endl;
> +			return TestFail;
> +		}

I would store the capture and output devices to local variables to
shorten the lines.

> +
> +		vim2m_->capture()->bufferReady.connect(this, &V4L2M2MDeviceTest::receiveCaptureBuffer);
> +		vim2m_->output()->bufferReady.connect(this, &V4L2M2MDeviceTest::outputBufferComplete);
> +
> +		/* We can't "queueAllBuffers()" on an output device, so we do it manually */
> +		std::vector<std::unique_ptr<Buffer>> outputBuffers;
> +		for (unsigned int i = 0; i < outputPool_.count(); ++i) {
> +			Buffer *buffer = new Buffer(i);
> +			outputBuffers.emplace_back(buffer);
> +			ret = vim2m_->output()->queueBuffer(buffer);
> +			if (ret)
> +				return {};
> +		}
> +
> +		std::vector<std::unique_ptr<Buffer>> captureBuffers;
> +		captureBuffers = vim2m_->capture()->queueAllBuffers();
> +		if (captureBuffers.empty()) {
> +			cerr << "Failed to queue all Capture Buffers" << endl;
> +			return TestFail;
> +		}

Even if it makes little difference in practice, I would queue the
buffers on the capture side first, 

> +
> +		ret = vim2m_->output()->streamOn();
> +		if (ret) {
> +			cerr << "Failed to streamOn output" << endl;
> +			return TestFail;
> +		}
> +
> +		ret = vim2m_->capture()->streamOn();
> +		if (ret) {
> +			cerr << "Failed to streamOn capture" << endl;
> +			return TestFail;
> +		}
> +
> +		timeout.start(10000);
> +		while (timeout.isRunning()) {
> +			dispatcher->processEvents();
> +			if (captureFrames_ > 30)
> +				break;

How long does it take in practice to capture 30 frames ? Can we reduce
the timeout ?

> +		}
> +
> +		if (captureFrames_ < 1) {
> +			std::cout << "Failed to capture any frames within timeout." << std::endl;

s/timeout\./timeout/
Line wrap.

> +			return TestFail;
> +		}
> +
> +		if (captureFrames_ < 30) {
> +			std::cout << "Failed to capture 30 frames within timeout." << std::endl;

Here too.

> +			return TestFail;
> +		}

You could merge the two checks and print the number of captured frames.

> +
> +		std::cout << "Output " << outputFrames_ << " frames" << std::endl;
> +		std::cout << "Captured " << captureFrames_ << " frames" << std::endl;
> +
> +		ret = vim2m_->capture()->streamOff();
> +		if (ret)

Error messages please.

> +			return TestFail;
> +
> +		ret = vim2m_->output()->streamOff();
> +		if (ret)
> +			return TestFail;
> +
> +		return TestPass;
> +	}
> +
> +	void cleanup()
> +	{
> +		delete vim2m_;
> +	};
> +
> +private:
> +	std::unique_ptr<DeviceEnumerator> enumerator_;
> +	std::shared_ptr<MediaDevice> media_;
> +	V4L2M2MDevice *vim2m_;
> +
> +	BufferPool capturePool_;
> +	BufferPool outputPool_;
> +
> +	unsigned int outputFrames_;
> +	unsigned int captureFrames_;
> +};
> +
> +TEST_REGISTER(V4L2M2MDeviceTest);

-- 
Regards,

Laurent Pinchart