3 files changed, 234 insertions, 0 deletions
diff --git a/src/android/mm/cros_camera_buffer.cpp b/src/android/mm/cros_camera_buffer.cpp
new file mode 100644
index 00000000..bb55b95e
--- /dev/null
+++ b/src/android/mm/cros_camera_buffer.cpp
@@ -0,0 +1,134 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * cros_camera_buffer.cpp - Chromium OS buffer backend using CameraBufferManager
+ */
+
+#include "../camera_buffer.h"
+
+#include <libcamera/base/log.h>
+
+#include "cros-camera/camera_buffer_manager.h"
+
+using namespace libcamera;
+
+LOG_DECLARE_CATEGORY(HAL)
+
+class CameraBuffer::Private : public Extensible::Private
+{
+	LIBCAMERA_DECLARE_PUBLIC(CameraBuffer)
+
+public:
+	Private(CameraBuffer *cameraBuffer,
+		buffer_handle_t camera3Buffer, int flags);
+	~Private();
+
+	bool isValid() const { return valid_; }
+
+	unsigned int numPlanes() const;
+
+	Span<uint8_t> plane(unsigned int plane);
+
+	size_t jpegBufferSize(size_t maxJpegBufferSize) const;
+
+private:
+	cros::CameraBufferManager *bufferManager_;
+	buffer_handle_t handle_;
+	unsigned int numPlanes_;
+	bool valid_;
+	bool registered_;
+	union {
+		void *addr;
+		android_ycbcr ycbcr;
+	} mem;
+};
+
+CameraBuffer::Private::Private(CameraBuffer *cameraBuffer,
+			       buffer_handle_t camera3Buffer,
+			       [[maybe_unused]] int flags)
+	: Extensible::Private(cameraBuffer), handle_(camera3Buffer),
+	  numPlanes_(0), valid_(false), registered_(false)
+{
+	bufferManager_ = cros::CameraBufferManager::GetInstance();
+
+	int ret = bufferManager_->Register(camera3Buffer);
+	if (ret) {
+		LOG(HAL, Error) << "Failed registering a buffer: " << ret;
+		return;
+	}
+
+	registered_ = true;
+	numPlanes_ = bufferManager_->GetNumPlanes(camera3Buffer);
+	switch (numPlanes_) {
+	case 1: {
+		ret = bufferManager_->Lock(handle_, 0, 0, 0, 0, 0, &mem.addr);
+		if (ret) {
+			LOG(HAL, Error) << "Single plane buffer mapping failed";
+			return;
+		}
+		break;
+	}
+	case 2:
+	case 3: {
+		ret = bufferManager_->LockYCbCr(handle_, 0, 0, 0, 0, 0,
+						&mem.ycbcr);
+		if (ret) {
+			LOG(HAL, Error) << "YCbCr buffer mapping failed";
+			return;
+		}
+		break;
+	}
+	default:
+		LOG(HAL, Error) << "Invalid number of planes: " << numPlanes_;
+		return;
+	}
+
+	valid_ = true;
+}
+
+CameraBuffer::Private::~Private()
+{
+	if (valid_)
+		bufferManager_->Unlock(handle_);
+	if (registered_)
+		bufferManager_->Deregister(handle_);
+}
+
+unsigned int CameraBuffer::Private::numPlanes() const
+{
+	return bufferManager_->GetNumPlanes(handle_);
+}
+
+Span<uint8_t> CameraBuffer::Private::plane(unsigned int plane)
+{
+	void *addr;
+
+	switch (numPlanes()) {
+	case 1:
+		addr = mem.addr;
+		break;
+	default:
+		switch (plane) {
+		case 0:
+			addr = mem.ycbcr.y;
+			break;
+		case 1:
+			addr = mem.ycbcr.cb;
+			break;
+		case 2:
+			addr = mem.ycbcr.cr;
+			break;
+		}
+	}
+
+	return { static_cast<uint8_t *>(addr),
+		 bufferManager_->GetPlaneSize(handle_, plane) };
+}
+
+size_t CameraBuffer::Private::jpegBufferSize([[maybe_unused]] size_t maxJpegBufferSize) const
+{
+	return bufferManager_->GetPlaneSize(handle_, 0);
+}
+
+PUBLIC_CAMERA_BUFFER_IMPLEMENTATION
diff --git a/src/android/mm/generic_camera_buffer.cpp b/src/android/mm/generic_camera_buffer.cpp
new file mode 100644
index 00000000..166be36e
--- /dev/null
+++ b/src/android/mm/generic_camera_buffer.cpp
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * generic_camera_buffer.cpp - Generic Android frame buffer backend
+ */
+
+#include "../camera_buffer.h"
+
+#include <unistd.h>
+
+#include <libcamera/base/log.h>
+
+#include "libcamera/internal/framebuffer.h"
+
+using namespace libcamera;
+
+LOG_DECLARE_CATEGORY(HAL)
+
+class CameraBuffer::Private : public Extensible::Private,
+			      public libcamera::MappedBuffer
+{
+	LIBCAMERA_DECLARE_PUBLIC(CameraBuffer)
+
+public:
+	Private(CameraBuffer *cameraBuffer,
+		buffer_handle_t camera3Buffer, int flags);
+	~Private();
+
+	unsigned int numPlanes() const;
+
+	Span<uint8_t> plane(unsigned int plane);
+
+	size_t jpegBufferSize(size_t maxJpegBufferSize) const;
+};
+
+CameraBuffer::Private::Private(CameraBuffer *cameraBuffer,
+			       buffer_handle_t camera3Buffer, int flags)
+	: Extensible::Private(cameraBuffer)
+{
+	maps_.reserve(camera3Buffer->numFds);
+	error_ = 0;
+
+	for (int i = 0; i < camera3Buffer->numFds; i++) {
+		if (camera3Buffer->data[i] == -1)
+			continue;
+
+		off_t length = lseek(camera3Buffer->data[i], 0, SEEK_END);
+		if (length < 0) {
+			error_ = -errno;
+			LOG(HAL, Error) << "Failed to query plane length";
+			break;
+		}
+
+		void *address = mmap(nullptr, length, flags, MAP_SHARED,
+				     camera3Buffer->data[i], 0);
+		if (address == MAP_FAILED) {
+			error_ = -errno;
+			LOG(HAL, Error) << "Failed to mmap plane";
+			break;
+		}
+
+		maps_.emplace_back(static_cast<uint8_t *>(address),
+				   static_cast<size_t>(length));
+	}
+}
+
+CameraBuffer::Private::~Private()
+{
+}
+
+unsigned int CameraBuffer::Private::numPlanes() const
+{
+	return maps_.size();
+}
+
+Span<uint8_t> CameraBuffer::Private::plane(unsigned int plane)
+{
+	if (plane >= maps_.size())
+		return {};
+
+	return maps_[plane];
+}
+
+size_t CameraBuffer::Private::jpegBufferSize(size_t maxJpegBufferSize) const
+{
+	return std::min<unsigned int>(maps_[0].size(),
+				      maxJpegBufferSize);
+}
+
+PUBLIC_CAMERA_BUFFER_IMPLEMENTATION
diff --git a/src/android/mm/meson.build b/src/android/mm/meson.build
new file mode 100644
index 00000000..eeb5cc2e
--- /dev/null
+++ b/src/android/mm/meson.build
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: CC0-1.0
+
+platform = get_option('android_platform')
+if platform == 'generic'
+    android_hal_sources += files(['generic_camera_buffer.cpp'])
+elif platform == 'cros'
+    android_hal_sources += files(['cros_camera_buffer.cpp'])
+    android_deps += [dependency('libcros_camera')]
+endif