libcamera: pipeline: Add Intel IPU3 pipeline

Add a pipeline handler for the Intel IPU3 device.

The pipeline handler creates a Camera for each image sensor it finds to be
connected to an IPU3 CSI-2 receiver, and enables the link between the two.

Tested on Soraka, listing detected cameras on the system, verifying the
pipeline handler gets matched and links properly enabled.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -0,0 +1,185 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * ipu3.cpp - Pipeline handler for Intel IPU3
+ */
+
+#include <memory>
+#include <vector>
+
+#include <libcamera/camera.h>
+#include <libcamera/camera_manager.h>
+
+#include "device_enumerator.h"
+#include "log.h"
+#include "media_device.h"
+#include "pipeline_handler.h"
+
+namespace libcamera {
+
+class PipelineHandlerIPU3 : public PipelineHandler
+{
+public:
+	PipelineHandlerIPU3();
+	~PipelineHandlerIPU3();
+
+	bool match(CameraManager *manager, DeviceEnumerator *enumerator);
+
+private:
+	MediaDevice *cio2_;
+	MediaDevice *imgu_;
+
+	void registerCameras(CameraManager *manager);
+};
+
+PipelineHandlerIPU3::PipelineHandlerIPU3()
+	: cio2_(nullptr), imgu_(nullptr)
+{
+}
+
+PipelineHandlerIPU3::~PipelineHandlerIPU3()
+{
+	if (cio2_)
+		cio2_->release();
+
+	if (imgu_)
+		imgu_->release();
+
+	cio2_ = nullptr;
+	imgu_ = nullptr;
+}
+
+bool PipelineHandlerIPU3::match(CameraManager *manager, DeviceEnumerator *enumerator)
+{
+	DeviceMatch cio2_dm("ipu3-cio2");
+	cio2_dm.add("ipu3-csi2 0");
+	cio2_dm.add("ipu3-cio2 0");
+	cio2_dm.add("ipu3-csi2 1");
+	cio2_dm.add("ipu3-cio2 1");
+	cio2_dm.add("ipu3-csi2 2");
+	cio2_dm.add("ipu3-cio2 2");
+	cio2_dm.add("ipu3-csi2 3");
+	cio2_dm.add("ipu3-cio2 3");
+
+	DeviceMatch imgu_dm("ipu3-imgu");
+	imgu_dm.add("ipu3-imgu 0");
+	imgu_dm.add("ipu3-imgu 0 input");
+	imgu_dm.add("ipu3-imgu 0 parameters");
+	imgu_dm.add("ipu3-imgu 0 output");
+	imgu_dm.add("ipu3-imgu 0 viewfinder");
+	imgu_dm.add("ipu3-imgu 0 3a stat");
+	imgu_dm.add("ipu3-imgu 1");
+	imgu_dm.add("ipu3-imgu 1 input");
+	imgu_dm.add("ipu3-imgu 1 parameters");
+	imgu_dm.add("ipu3-imgu 1 output");
+	imgu_dm.add("ipu3-imgu 1 viewfinder");
+	imgu_dm.add("ipu3-imgu 1 3a stat");
+
+	cio2_ = enumerator->search(cio2_dm);
+	if (!cio2_)
+		return false;
+
+	imgu_ = enumerator->search(imgu_dm);
+	if (!imgu_)
+		return false;
+
+	/*
+	 * It is safe to acquire both media devices at this point as
+	 * DeviceEnumerator::search() skips the busy ones for us.
+	 */
+	cio2_->acquire();
+	imgu_->acquire();
+
+	/*
+	 * Disable all links that are enabled by default on CIO2, as camera
+	 * creation enables all valid links it finds.
+	 *
+	 * Close the CIO2 media device after, as links are enabled and should
+	 * not need to be changed after.
+	 */
+	if (cio2_->open())
+		goto error_release_mdev;
+
+	if (cio2_->disableLinks())
+		goto error_close_cio2;
+
+	registerCameras(manager);
+
+	cio2_->close();
+
+	return true;
+
+error_close_cio2:
+	cio2_->close();
+
+error_release_mdev:
+	cio2_->release();
+	imgu_->release();
+
+	return false;
+}
+
+/*
+ * Cameras are created associating an image sensor (represented by a
+ * media entity with function MEDIA_ENT_F_CAM_SENSOR) to one of the four
+ * CIO2 CSI-2 receivers.
+ */
+void PipelineHandlerIPU3::registerCameras(CameraManager *manager)
+{
+	/*
+	 * For each CSI-2 receiver on the IPU3, create a Camera if an
+	 * image sensor is connected to it.
+	 */
+	unsigned int numCameras = 0;
+	for (unsigned int id = 0; id < 4; ++id) {
+		std::string csi2Name = "ipu3-csi2 " + std::to_string(id);
+		MediaEntity *csi2 = cio2_->getEntityByName(csi2Name);
+
+		/*
+		 * This shall not happen, as the device enumerator matched
+		 * all entities described in the cio2_dm DeviceMatch.
+		 *
+		 * As this check is basically free, better stay safe than sorry.
+		 */
+		if (!csi2)
+			continue;
+
+		const std::vector<MediaPad *> &pads = csi2->pads();
+		if (pads.empty())
+			continue;
+
+		/* IPU3 CSI-2 receivers have a single sink pad at index 0. */
+		MediaPad *sink = pads[0];
+		const std::vector<MediaLink *> &links = sink->links();
+		if (links.empty())
+			continue;
+
+		/*
+		 * Verify that the receiver is connected to a sensor, enable
+		 * the media link between the two, and create a Camera with
+		 * a unique name.
+		 */
+		MediaLink *link = links[0];
+		MediaEntity *sensor = link->source()->entity();
+		if (sensor->function() != MEDIA_ENT_F_CAM_SENSOR)
+			continue;
+
+		if (link->setEnabled(true))
+			continue;
+
+		std::string cameraName = sensor->name() + " " + std::to_string(id);
+		std::shared_ptr<Camera> camera = Camera::create(cameraName);
+		manager->addCamera(std::move(camera));
+
+		LOG(Info) << "Registered Camera[" << numCameras << "] \""
+			  << cameraName << "\""
+			  << " connected to CSI-2 receiver " << id;
+
+		numCameras++;
+	}
+}
+
+REGISTER_PIPELINE_HANDLER(PipelineHandlerIPU3);
+
+} /* namespace libcamera */

src/libcamera/pipeline/ipu3/meson.build

@@ -0,0 +1,3 @@
+libcamera_sources += files([
+    'ipu3.cpp',
+])

src/libcamera/pipeline/meson.build

@@ -1,3 +1,5 @@
 libcamera_sources += files([
     'vimc.cpp',
 ])
+
+subdir('ipu3')