bluetooth: add aidl hal

* Copy from hardware/interfaces/bluetooth/aidl/default
  at 488942f82bd1bc9ad1cb65a02c71421dc3a6a3d6.

bluetooth/BluetoothHci.h

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <aidl/android/hardware/bluetooth/BnBluetoothHci.h>
+#include <aidl/android/hardware/bluetooth/IBluetoothHciCallbacks.h>
+
+#include <future>
+#include <string>
+
+#include "async_fd_watcher.h"
+#include "h4_protocol.h"
+#include "net_bluetooth_mgmt.h"
+
+namespace aidl::android::hardware::bluetooth::impl {
+
+class BluetoothDeathRecipient;
+
+// This Bluetooth HAL implementation connects with a serial port at dev_path_.
+class BluetoothHci : public BnBluetoothHci {
+ public:
+  BluetoothHci(const std::string& dev_path = "/dev/hvc5");
+
+  ndk::ScopedAStatus initialize(
+      const std::shared_ptr<IBluetoothHciCallbacks>& cb) override;
+
+  ndk::ScopedAStatus sendHciCommand(
+      const std::vector<uint8_t>& packet) override;
+
+  ndk::ScopedAStatus sendAclData(const std::vector<uint8_t>& packet) override;
+
+  ndk::ScopedAStatus sendScoData(const std::vector<uint8_t>& packet) override;
+
+  ndk::ScopedAStatus sendIsoData(const std::vector<uint8_t>& packet) override;
+
+  ndk::ScopedAStatus close() override;
+
+  static void OnPacketReady();
+
+  static BluetoothHci* get();
+
+ private:
+  int mFd{-1};
+  std::shared_ptr<IBluetoothHciCallbacks> mCb = nullptr;
+
+  std::shared_ptr<::android::hardware::bluetooth::hci::H4Protocol> mH4;
+
+  std::shared_ptr<BluetoothDeathRecipient> mDeathRecipient;
+
+  std::string mDevPath;
+
+  ::android::hardware::bluetooth::async::AsyncFdWatcher mFdWatcher;
+
+  int getFdFromDevPath();
+  [[nodiscard]] ndk::ScopedAStatus send(
+      ::android::hardware::bluetooth::hci::PacketType type,
+      const std::vector<uint8_t>& packet);
+  std::unique_ptr<NetBluetoothMgmt> management_{};
+
+  // Send a reset command and discard all packets until a reset is received.
+  void reset();
+
+  // Don't close twice or open before close is complete
+  std::mutex mStateMutex;
+  enum class HalState {
+    READY,
+    INITIALIZING,
+    ONE_CLIENT,
+    CLOSING,
+  } mState{HalState::READY};
+};
+
+}  // namespace aidl::android::hardware::bluetooth::impl