cam: Add KMS sink class

Add a KMSSink class to display framebuffers through the DRM/KMS API.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/src/cam/kms_sink.h b/src/cam/kms_sink.h
new file mode 100644
index 00000000..0c01df40
--- /dev/null
+++ b/src/cam/kms_sink.h
@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2021, Ideas on Board Oy
+ *
+ * kms_sink.h - KMS Sink
+ */
+#ifndef __CAM_KMS_SINK_H__
+#define __CAM_KMS_SINK_H__
+
+#include <list>
+#include <memory>
+#include <mutex>
+#include <string>
+#include <utility>
+
+#include <libcamera/base/signal.h>
+
+#include <libcamera/geometry.h>
+#include <libcamera/pixel_format.h>
+
+#include "drm.h"
+#include "frame_sink.h"
+
+class KMSSink : public FrameSink
+{
+public:
+	KMSSink(const std::string &connectorName);
+
+	void mapBuffer(libcamera::FrameBuffer *buffer) override;
+
+	int configure(const libcamera::CameraConfiguration &config) override;
+	int start() override;
+	int stop() override;
+
+	bool processRequest(libcamera::Request *request) override;
+
+private:
+	class Request
+	{
+	public:
+		Request(DRM::AtomicRequest *drmRequest, libcamera::Request *camRequest)
+			: drmRequest_(drmRequest), camRequest_(camRequest)
+		{
+		}
+
+		std::unique_ptr<DRM::AtomicRequest> drmRequest_;
+		libcamera::Request *camRequest_;
+	};
+
+	int configurePipeline(const libcamera::PixelFormat &format);
+	void requestComplete(DRM::AtomicRequest *request);
+
+	DRM::Device dev_;
+
+	const DRM::Connector *connector_;
+	const DRM::Crtc *crtc_;
+	const DRM::Plane *plane_;
+	const DRM::Mode *mode_;
+
+	libcamera::PixelFormat format_;
+	libcamera::Size size_;
+	unsigned int stride_;
+
+	bool planeInitialized_;
+
+	std::map<libcamera::FrameBuffer *, std::unique_ptr<DRM::FrameBuffer>> buffers_;
+
+	std::mutex lock_;
+	std::unique_ptr<Request> pending_;
+	std::unique_ptr<Request> queued_;
+	std::unique_ptr<Request> active_;
+};
+
+#endif /* __CAM_KMS_SINK_H__ */