services/core/jni/BroadcastRadio/TunerCallback.cpp - platform/frameworks/base - Git at Google

 /**
  * Copyright (C) 2017 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.
  */

 #define LOG_TAG "BroadcastRadioService.TunerCallback.jni"
 #define LOG_NDEBUG 0

 #include "TunerCallback.h"

 #include "Tuner.h"
 #include "convert.h"

 #include <broadcastradio-utils/Utils.h>
 #include <core_jni_helpers.h>
 #include <nativehelper/JNIHelp.h>
 #include <utils/Log.h>

 namespace android {
 namespace server {
 namespace BroadcastRadio {
 namespace TunerCallback {

 using std::lock_guard;
 using std::mutex;

 using hardware::Return;
 using hardware::hidl_vec;

 namespace V1_0 = hardware::broadcastradio::V1_0;
 namespace V1_1 = hardware::broadcastradio::V1_1;

 using V1_0::Band;
 using V1_0::BandConfig;
 using V1_0::MetaData;
 using V1_0::Result;
 using V1_1::ITunerCallback;
 using V1_1::ProgramInfo;
 using V1_1::ProgramListResult;
 using V1_1::ProgramSelector;

 static JavaVM *gvm = nullptr;

 static struct {
     struct {
         jclass clazz;
         jfieldID nativeContext;
         jmethodID handleHwFailure;
         jmethodID onError;
         jmethodID onConfigurationChanged;
         jmethodID onCurrentProgramInfoChanged;
         jmethodID onTrafficAnnouncement;
         jmethodID onEmergencyAnnouncement;
         jmethodID onAntennaState;
         jmethodID onBackgroundScanAvailabilityChange;
         jmethodID onBackgroundScanComplete;
         jmethodID onProgramListChanged;
     } TunerCallback;
 } gjni;

 // from frameworks/base/core/java/android/hardware/radio/RadioTuner.java
 enum class TunerError : jint {
     HARDWARE_FAILURE = 0,
     SERVER_DIED = 1,
     CANCELLED = 2,
     SCAN_TIMEOUT = 3,
     CONFIG = 4,
     BACKGROUND_SCAN_UNAVAILABLE = 5,
     BACKGROUND_SCAN_FAILED = 6,
 };

 static mutex gContextMutex;

 class NativeCallback : public ITunerCallback {
     mutex mMut;

     jobject mJTuner;
     jobject mJCallback;
     NativeCallbackThread mCallbackThread;
     HalRevision mHalRev;

     Band mBand;

     // Carries current program info data for 1.0 newMetadata callback.
     V1_0::ProgramInfo mCurrentProgramInfo;

     DISALLOW_COPY_AND_ASSIGN(NativeCallback);

 public:
     NativeCallback(JNIEnv *env, jobject jTuner, jobject jCallback, HalRevision halRev);
     virtual ~NativeCallback();

     void detach();

     virtual Return<void> hardwareFailure();
     virtual Return<void> configChange(Result result, const BandConfig& config);
     virtual Return<void> tuneComplete(Result result, const V1_0::ProgramInfo& info);
     virtual Return<void> afSwitch(const V1_0::ProgramInfo& info);
     virtual Return<void> antennaStateChange(bool connected);
     virtual Return<void> trafficAnnouncement(bool active);
     virtual Return<void> emergencyAnnouncement(bool active);
     virtual Return<void> newMetadata(uint32_t channel, uint32_t subChannel,
             const hidl_vec<MetaData>& metadata);
     virtual Return<void> tuneComplete_1_1(Result result, const ProgramSelector& selector);
     virtual Return<void> backgroundScanAvailable(bool isAvailable);
     virtual Return<void> backgroundScanComplete(ProgramListResult result);
     virtual Return<void> programListChanged();
     virtual Return<void> currentProgramInfoChanged(const ProgramInfo& info);
 };

 struct TunerCallbackContext {
     TunerCallbackContext() {}

     sp<NativeCallback> mNativeCallback;

 private:
     DISALLOW_COPY_AND_ASSIGN(TunerCallbackContext);
 };

 NativeCallback::NativeCallback(JNIEnv *env, jobject jTuner, jobject jCallback, HalRevision halRev)
         : mCallbackThread(gvm), mHalRev(halRev) {
     ALOGV("%s", __func__);
     mJTuner = env->NewGlobalRef(jTuner);
     mJCallback = env->NewGlobalRef(jCallback);
 }

 NativeCallback::~NativeCallback() {
     ALOGV("%s", __func__);

     // stop callback thread before dereferencing client callback
     mCallbackThread.stop();

     JNIEnv *env = nullptr;
     gvm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_4);
     if (env != nullptr) {
         env->DeleteGlobalRef(mJTuner);
         env->DeleteGlobalRef(mJCallback);
     }
 }

 void NativeCallback::detach() {
     // stop callback thread to ignore further calls
     mCallbackThread.stop();
 }

 Return<void> NativeCallback::hardwareFailure() {
     mCallbackThread.enqueue([this](JNIEnv *env) {
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.handleHwFailure);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::configChange(Result result, const BandConfig& config) {
     ALOGV("%s(%d)", __func__, result);

     mCallbackThread.enqueue([result, config, this](JNIEnv *env) {
         if (result == Result::OK) {
             auto region = Tuner::getRegion(env, mJTuner);
             auto jConfig = convert::BandConfigFromHal(env, config, region);
             if (jConfig == nullptr) return;
             env->CallVoidMethod(mJCallback, gjni.TunerCallback.onConfigurationChanged,
                     jConfig.get());
         } else {
             env->CallVoidMethod(mJCallback, gjni.TunerCallback.onError, TunerError::CONFIG);
         }
     });

     return Return<void>();
 }

 Return<void> NativeCallback::tuneComplete(Result result, const V1_0::ProgramInfo& info) {
     ALOGV("%s(%d)", __func__, result);

     if (mHalRev > HalRevision::V1_0) {
         ALOGW("1.0 callback was ignored");
         return {};
     }

     if (result == Result::OK) {
         {
             lock_guard<mutex> lk(mMut);
             mCurrentProgramInfo = info;
         }

         // tuneComplete_1_1 implementation does not handle success case, see the implementation
         mCallbackThread.enqueue([this, info](JNIEnv *env) {
             auto jInfo = convert::ProgramInfoFromHal(env, info, mBand);
             env->CallVoidMethod(mJCallback, gjni.TunerCallback.onCurrentProgramInfoChanged,
                     jInfo.get());
         });
         return {};
     }

     auto selector = V1_1::utils::make_selector(mBand, info.channel, info.subChannel);
     return tuneComplete_1_1(result, selector);
 }

 Return<void> NativeCallback::tuneComplete_1_1(Result result, const ProgramSelector& selector) {
     ALOGV("%s(%d)", __func__, result);

     mCallbackThread.enqueue([result, this](JNIEnv *env) {
         /* for HAL 1.1, onCurrentProgramInfoChanged will be called from currentProgramInfoChanged,
          * so we don't need to handle success case here.
          */
         if (result == Result::OK) return;

         TunerError cause = TunerError::CANCELLED;
         if (result == Result::TIMEOUT) cause = TunerError::SCAN_TIMEOUT;
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onError, cause);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::afSwitch(const V1_0::ProgramInfo& info) {
     ALOGV("%s", __func__);
     return tuneComplete(Result::OK, info);
 }

 Return<void> NativeCallback::antennaStateChange(bool connected) {
     ALOGV("%s(%d)", __func__, connected);

     mCallbackThread.enqueue([this, connected](JNIEnv *env) {
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onAntennaState, connected);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::trafficAnnouncement(bool active) {
     ALOGV("%s(%d)", __func__, active);

     mCallbackThread.enqueue([this, active](JNIEnv *env) {
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onTrafficAnnouncement, active);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::emergencyAnnouncement(bool active) {
     ALOGV("%s(%d)", __func__, active);

     mCallbackThread.enqueue([this, active](JNIEnv *env) {
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onEmergencyAnnouncement, active);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::newMetadata(uint32_t channel, uint32_t subChannel,
         const hidl_vec<MetaData>& metadata) {
     ALOGV("%s(%d, %d)", __func__, channel, subChannel);

     if (mHalRev > HalRevision::V1_0) {
         ALOGW("1.0 callback was ignored");
         return {};
     }

     V1_0::ProgramInfo info;
     {
         lock_guard<mutex> lk(mMut);
         info = mCurrentProgramInfo;
     }
     if (channel != info.channel || subChannel != info.subChannel) {
         ALOGE("Channel mismatch on newMetadata callback (%d.%d != %d.%d)",
                 channel, subChannel, info.channel, info.subChannel);
         return {};
     }
     info.metadata = metadata;

     mCallbackThread.enqueue([this, info](JNIEnv *env) {
         auto jInfo = convert::ProgramInfoFromHal(env, info, mBand);
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onCurrentProgramInfoChanged,
                 jInfo.get());
     });

     return {};
 }

 Return<void> NativeCallback::backgroundScanAvailable(bool isAvailable) {
     ALOGV("%s(%d)", __func__, isAvailable);

     mCallbackThread.enqueue([this, isAvailable](JNIEnv *env) {
         env->CallVoidMethod(mJCallback,
                 gjni.TunerCallback.onBackgroundScanAvailabilityChange, isAvailable);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::backgroundScanComplete(ProgramListResult result) {
     ALOGV("%s(%d)", __func__, result);

     mCallbackThread.enqueue([this, result](JNIEnv *env) {
         if (result == ProgramListResult::OK) {
             env->CallVoidMethod(mJCallback, gjni.TunerCallback.onBackgroundScanComplete);
         } else {
             auto cause = (result == ProgramListResult::UNAVAILABLE) ?
                     TunerError::BACKGROUND_SCAN_UNAVAILABLE : TunerError::BACKGROUND_SCAN_FAILED;
             env->CallVoidMethod(mJCallback, gjni.TunerCallback.onError, cause);
         }
     });

     return Return<void>();
 }

 Return<void> NativeCallback::programListChanged() {
     ALOGV("%s", __func__);

     mCallbackThread.enqueue([this](JNIEnv *env) {
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onProgramListChanged);
     });

     return Return<void>();
 }

 Return<void> NativeCallback::currentProgramInfoChanged(const ProgramInfo& info) {
     ALOGV("%s(%s)", __func__, toString(info).substr(0, 100).c_str());

     mCallbackThread.enqueue([this, info](JNIEnv *env) {
         auto jInfo = convert::ProgramInfoFromHal(env, info);
         env->CallVoidMethod(mJCallback, gjni.TunerCallback.onCurrentProgramInfoChanged,
                 jInfo.get());
     });

     return Return<void>();
 }

 static TunerCallbackContext& getNativeContext(jlong nativeContextHandle) {
     auto nativeContext = reinterpret_cast<TunerCallbackContext*>(nativeContextHandle);
     LOG_ALWAYS_FATAL_IF(nativeContext == nullptr, "Native context not initialized");
     return *nativeContext;
 }

 /**
  * Always lock gContextMutex when using native context.
  */
 static TunerCallbackContext& getNativeContext(JNIEnv *env, jobject jTunerCb) {
     return getNativeContext(env->GetLongField(jTunerCb, gjni.TunerCallback.nativeContext));
 }

 static jlong nativeInit(JNIEnv *env, jobject obj, jobject jTuner, jint jHalRev) {
     ALOGV("%s", __func__);
     lock_guard<mutex> lk(gContextMutex);

     auto halRev = static_cast<HalRevision>(jHalRev);

     auto ctx = new TunerCallbackContext();
     ctx->mNativeCallback = new NativeCallback(env, jTuner, obj, halRev);

     static_assert(sizeof(jlong) >= sizeof(ctx), "jlong is smaller than a pointer");
     return reinterpret_cast<jlong>(ctx);
 }

 static void nativeFinalize(JNIEnv *env, jobject obj, jlong nativeContext) {
     ALOGV("%s", __func__);
     lock_guard<mutex> lk(gContextMutex);

     auto ctx = reinterpret_cast<TunerCallbackContext*>(nativeContext);
     delete ctx;
 }

 static void nativeDetach(JNIEnv *env, jobject obj, jlong nativeContext) {
     ALOGV("%s", __func__);
     lock_guard<mutex> lk(gContextMutex);
     auto& ctx = getNativeContext(nativeContext);

     if (ctx.mNativeCallback == nullptr) return;
     ctx.mNativeCallback->detach();
     ctx.mNativeCallback = nullptr;
 }

 sp<ITunerCallback> getNativeCallback(JNIEnv *env, jobject jTunerCallback) {
     lock_guard<mutex> lk(gContextMutex);
     auto& ctx = getNativeContext(env, jTunerCallback);
     return ctx.mNativeCallback;
 }

 static const JNINativeMethod gTunerCallbackMethods[] = {
     { "nativeInit", "(Lcom/android/server/broadcastradio/Tuner;I)J", (void*)nativeInit },
     { "nativeFinalize", "(J)V", (void*)nativeFinalize },
     { "nativeDetach", "(J)V", (void*)nativeDetach },
 };

 } // namespace TunerCallback
 } // namespace BroadcastRadio
 } // namespace server

 void register_android_server_broadcastradio_TunerCallback(JavaVM *vm, JNIEnv *env) {
     using namespace server::BroadcastRadio::TunerCallback;

     gvm = vm;

     auto tunerCbClass = FindClassOrDie(env, "com/android/server/broadcastradio/TunerCallback");
     gjni.TunerCallback.clazz = MakeGlobalRefOrDie(env, tunerCbClass);
     gjni.TunerCallback.nativeContext = GetFieldIDOrDie(env, tunerCbClass, "mNativeContext", "J");
     gjni.TunerCallback.handleHwFailure = GetMethodIDOrDie(env, tunerCbClass, "handleHwFailure", "()V");
     gjni.TunerCallback.onError = GetMethodIDOrDie(env, tunerCbClass, "onError", "(I)V");
     gjni.TunerCallback.onConfigurationChanged = GetMethodIDOrDie(env, tunerCbClass,
             "onConfigurationChanged", "(Landroid/hardware/radio/RadioManager$BandConfig;)V");
     gjni.TunerCallback.onCurrentProgramInfoChanged = GetMethodIDOrDie(env, tunerCbClass,
             "onCurrentProgramInfoChanged", "(Landroid/hardware/radio/RadioManager$ProgramInfo;)V");
     gjni.TunerCallback.onTrafficAnnouncement = GetMethodIDOrDie(env, tunerCbClass,
             "onTrafficAnnouncement", "(Z)V");
     gjni.TunerCallback.onEmergencyAnnouncement = GetMethodIDOrDie(env, tunerCbClass,
             "onEmergencyAnnouncement", "(Z)V");
     gjni.TunerCallback.onAntennaState = GetMethodIDOrDie(env, tunerCbClass,
             "onAntennaState", "(Z)V");
     gjni.TunerCallback.onBackgroundScanAvailabilityChange = GetMethodIDOrDie(env, tunerCbClass,
             "onBackgroundScanAvailabilityChange", "(Z)V");
     gjni.TunerCallback.onBackgroundScanComplete = GetMethodIDOrDie(env, tunerCbClass,
             "onBackgroundScanComplete", "()V");
     gjni.TunerCallback.onProgramListChanged = GetMethodIDOrDie(env, tunerCbClass,
             "onProgramListChanged", "()V");

     auto res = jniRegisterNativeMethods(env, "com/android/server/broadcastradio/TunerCallback",
             gTunerCallbackMethods, NELEM(gTunerCallbackMethods));
     LOG_ALWAYS_FATAL_IF(res < 0, "Unable to register native methods.");
 }

 } // namespace android
	/**
	* Copyright (C) 2017 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.
	*/

	#define LOG_TAG "BroadcastRadioService.TunerCallback.jni"
	#define LOG_NDEBUG 0

	#include "TunerCallback.h"

	#include "Tuner.h"
	#include "convert.h"

	#include <broadcastradio-utils/Utils.h>
	#include <core_jni_helpers.h>
	#include <nativehelper/JNIHelp.h>
	#include <utils/Log.h>

	namespace android {
	namespace server {
	namespace BroadcastRadio {
	namespace TunerCallback {

	using std::lock_guard;
	using std::mutex;

	using hardware::Return;
	using hardware::hidl_vec;

	namespace V1_0 = hardware::broadcastradio::V1_0;
	namespace V1_1 = hardware::broadcastradio::V1_1;

	using V1_0::Band;
	using V1_0::BandConfig;
	using V1_0::MetaData;
	using V1_0::Result;
	using V1_1::ITunerCallback;
	using V1_1::ProgramInfo;
	using V1_1::ProgramListResult;
	using V1_1::ProgramSelector;

	static JavaVM *gvm = nullptr;

	static struct {
	struct {
	jclass clazz;
	jfieldID nativeContext;
	jmethodID handleHwFailure;
	jmethodID onError;
	jmethodID onConfigurationChanged;
	jmethodID onCurrentProgramInfoChanged;
	jmethodID onTrafficAnnouncement;
	jmethodID onEmergencyAnnouncement;
	jmethodID onAntennaState;
	jmethodID onBackgroundScanAvailabilityChange;
	jmethodID onBackgroundScanComplete;
	jmethodID onProgramListChanged;
	} TunerCallback;
	} gjni;

	// from frameworks/base/core/java/android/hardware/radio/RadioTuner.java
	enum class TunerError : jint {
	HARDWARE_FAILURE = 0,
	SERVER_DIED = 1,
	CANCELLED = 2,
	SCAN_TIMEOUT = 3,
	CONFIG = 4,
	BACKGROUND_SCAN_UNAVAILABLE = 5,
	BACKGROUND_SCAN_FAILED = 6,
	};

	static mutex gContextMutex;

	class NativeCallback : public ITunerCallback {
	mutex mMut;

	jobject mJTuner;
	jobject mJCallback;
	NativeCallbackThread mCallbackThread;
	HalRevision mHalRev;

	Band mBand;

	// Carries current program info data for 1.0 newMetadata callback.
	V1_0::ProgramInfo mCurrentProgramInfo;

	DISALLOW_COPY_AND_ASSIGN(NativeCallback);

	public:
	NativeCallback(JNIEnv *env, jobject jTuner, jobject jCallback, HalRevision halRev);
	virtual ~NativeCallback();

	void detach();

	virtual Return<void> hardwareFailure();
	virtual Return<void> configChange(Result result, const BandConfig& config);
	virtual Return<void> tuneComplete(Result result, const V1_0::ProgramInfo& info);
	virtual Return<void> afSwitch(const V1_0::ProgramInfo& info);
	virtual Return<void> antennaStateChange(bool connected);
	virtual Return<void> trafficAnnouncement(bool active);
	virtual Return<void> emergencyAnnouncement(bool active);
	virtual Return<void> newMetadata(uint32_t channel, uint32_t subChannel,
	const hidl_vec<MetaData>& metadata);
	virtual Return<void> tuneComplete_1_1(Result result, const ProgramSelector& selector);
	virtual Return<void> backgroundScanAvailable(bool isAvailable);
	virtual Return<void> backgroundScanComplete(ProgramListResult result);
	virtual Return<void> programListChanged();
	virtual Return<void> currentProgramInfoChanged(const ProgramInfo& info);
	};

	struct TunerCallbackContext {
	TunerCallbackContext() {}

	sp<NativeCallback> mNativeCallback;

	private:
	DISALLOW_COPY_AND_ASSIGN(TunerCallbackContext);
	};

	NativeCallback::NativeCallback(JNIEnv *env, jobject jTuner, jobject jCallback, HalRevision halRev)
	: mCallbackThread(gvm), mHalRev(halRev) {
	ALOGV("%s", __func__);
	mJTuner = env->NewGlobalRef(jTuner);
	mJCallback = env->NewGlobalRef(jCallback);
	}

	NativeCallback::~NativeCallback() {
	ALOGV("%s", __func__);

	// stop callback thread before dereferencing client callback
	mCallbackThread.stop();

	JNIEnv *env = nullptr;
	gvm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_4);
	if (env != nullptr) {
	env->DeleteGlobalRef(mJTuner);
	env->DeleteGlobalRef(mJCallback);
	}
	}

	void NativeCallback::detach() {
	// stop callback thread to ignore further calls
	mCallbackThread.stop();
	}

	Return<void> NativeCallback::hardwareFailure() {
	mCallbackThread.enqueue([this](JNIEnv *env) {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.handleHwFailure);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::configChange(Result result, const BandConfig& config) {
	ALOGV("%s(%d)", __func__, result);

	mCallbackThread.enqueue([result, config, this](JNIEnv *env) {
	if (result == Result::OK) {
	auto region = Tuner::getRegion(env, mJTuner);
	auto jConfig = convert::BandConfigFromHal(env, config, region);
	if (jConfig == nullptr) return;
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onConfigurationChanged,
	jConfig.get());
	} else {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onError, TunerError::CONFIG);
	}
	});

	return Return<void>();
	}

	Return<void> NativeCallback::tuneComplete(Result result, const V1_0::ProgramInfo& info) {
	ALOGV("%s(%d)", __func__, result);

	if (mHalRev > HalRevision::V1_0) {
	ALOGW("1.0 callback was ignored");
	return {};
	}

	if (result == Result::OK) {
	{
	lock_guard<mutex> lk(mMut);
	mCurrentProgramInfo = info;
	}

	// tuneComplete_1_1 implementation does not handle success case, see the implementation
	mCallbackThread.enqueue([this, info](JNIEnv *env) {
	auto jInfo = convert::ProgramInfoFromHal(env, info, mBand);
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onCurrentProgramInfoChanged,
	jInfo.get());
	});
	return {};
	}

	auto selector = V1_1::utils::make_selector(mBand, info.channel, info.subChannel);
	return tuneComplete_1_1(result, selector);
	}

	Return<void> NativeCallback::tuneComplete_1_1(Result result, const ProgramSelector& selector) {
	ALOGV("%s(%d)", __func__, result);

	mCallbackThread.enqueue([result, this](JNIEnv *env) {
	/* for HAL 1.1, onCurrentProgramInfoChanged will be called from currentProgramInfoChanged,
	* so we don't need to handle success case here.
	*/
	if (result == Result::OK) return;

	TunerError cause = TunerError::CANCELLED;
	if (result == Result::TIMEOUT) cause = TunerError::SCAN_TIMEOUT;
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onError, cause);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::afSwitch(const V1_0::ProgramInfo& info) {
	ALOGV("%s", __func__);
	return tuneComplete(Result::OK, info);
	}

	Return<void> NativeCallback::antennaStateChange(bool connected) {
	ALOGV("%s(%d)", __func__, connected);

	mCallbackThread.enqueue([this, connected](JNIEnv *env) {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onAntennaState, connected);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::trafficAnnouncement(bool active) {
	ALOGV("%s(%d)", __func__, active);

	mCallbackThread.enqueue([this, active](JNIEnv *env) {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onTrafficAnnouncement, active);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::emergencyAnnouncement(bool active) {
	ALOGV("%s(%d)", __func__, active);

	mCallbackThread.enqueue([this, active](JNIEnv *env) {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onEmergencyAnnouncement, active);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::newMetadata(uint32_t channel, uint32_t subChannel,
	const hidl_vec<MetaData>& metadata) {
	ALOGV("%s(%d, %d)", __func__, channel, subChannel);

	if (mHalRev > HalRevision::V1_0) {
	ALOGW("1.0 callback was ignored");
	return {};
	}

	V1_0::ProgramInfo info;
	{
	lock_guard<mutex> lk(mMut);
	info = mCurrentProgramInfo;
	}
	if (channel != info.channel \|\| subChannel != info.subChannel) {
	ALOGE("Channel mismatch on newMetadata callback (%d.%d != %d.%d)",
	channel, subChannel, info.channel, info.subChannel);
	return {};
	}
	info.metadata = metadata;

	mCallbackThread.enqueue([this, info](JNIEnv *env) {
	auto jInfo = convert::ProgramInfoFromHal(env, info, mBand);
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onCurrentProgramInfoChanged,
	jInfo.get());
	});

	return {};
	}

	Return<void> NativeCallback::backgroundScanAvailable(bool isAvailable) {
	ALOGV("%s(%d)", __func__, isAvailable);

	mCallbackThread.enqueue([this, isAvailable](JNIEnv *env) {
	env->CallVoidMethod(mJCallback,
	gjni.TunerCallback.onBackgroundScanAvailabilityChange, isAvailable);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::backgroundScanComplete(ProgramListResult result) {
	ALOGV("%s(%d)", __func__, result);

	mCallbackThread.enqueue([this, result](JNIEnv *env) {
	if (result == ProgramListResult::OK) {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onBackgroundScanComplete);
	} else {
	auto cause = (result == ProgramListResult::UNAVAILABLE) ?
	TunerError::BACKGROUND_SCAN_UNAVAILABLE : TunerError::BACKGROUND_SCAN_FAILED;
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onError, cause);
	}
	});

	return Return<void>();
	}

	Return<void> NativeCallback::programListChanged() {
	ALOGV("%s", __func__);

	mCallbackThread.enqueue([this](JNIEnv *env) {
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onProgramListChanged);
	});

	return Return<void>();
	}

	Return<void> NativeCallback::currentProgramInfoChanged(const ProgramInfo& info) {
	ALOGV("%s(%s)", __func__, toString(info).substr(0, 100).c_str());

	mCallbackThread.enqueue([this, info](JNIEnv *env) {
	auto jInfo = convert::ProgramInfoFromHal(env, info);
	env->CallVoidMethod(mJCallback, gjni.TunerCallback.onCurrentProgramInfoChanged,
	jInfo.get());
	});

	return Return<void>();
	}

	static TunerCallbackContext& getNativeContext(jlong nativeContextHandle) {
	auto nativeContext = reinterpret_cast<TunerCallbackContext*>(nativeContextHandle);
	LOG_ALWAYS_FATAL_IF(nativeContext == nullptr, "Native context not initialized");
	return *nativeContext;
	}

	/**
	* Always lock gContextMutex when using native context.
	*/
	static TunerCallbackContext& getNativeContext(JNIEnv *env, jobject jTunerCb) {
	return getNativeContext(env->GetLongField(jTunerCb, gjni.TunerCallback.nativeContext));
	}

	static jlong nativeInit(JNIEnv *env, jobject obj, jobject jTuner, jint jHalRev) {
	ALOGV("%s", __func__);
	lock_guard<mutex> lk(gContextMutex);

	auto halRev = static_cast<HalRevision>(jHalRev);

	auto ctx = new TunerCallbackContext();
	ctx->mNativeCallback = new NativeCallback(env, jTuner, obj, halRev);

	static_assert(sizeof(jlong) >= sizeof(ctx), "jlong is smaller than a pointer");
	return reinterpret_cast<jlong>(ctx);
	}

	static void nativeFinalize(JNIEnv *env, jobject obj, jlong nativeContext) {
	ALOGV("%s", __func__);
	lock_guard<mutex> lk(gContextMutex);

	auto ctx = reinterpret_cast<TunerCallbackContext*>(nativeContext);
	delete ctx;
	}

	static void nativeDetach(JNIEnv *env, jobject obj, jlong nativeContext) {
	ALOGV("%s", __func__);
	lock_guard<mutex> lk(gContextMutex);
	auto& ctx = getNativeContext(nativeContext);

	if (ctx.mNativeCallback == nullptr) return;
	ctx.mNativeCallback->detach();
	ctx.mNativeCallback = nullptr;
	}

	sp<ITunerCallback> getNativeCallback(JNIEnv *env, jobject jTunerCallback) {
	lock_guard<mutex> lk(gContextMutex);
	auto& ctx = getNativeContext(env, jTunerCallback);
	return ctx.mNativeCallback;
	}

	static const JNINativeMethod gTunerCallbackMethods[] = {
	{ "nativeInit", "(Lcom/android/server/broadcastradio/Tuner;I)J", (void*)nativeInit },
	{ "nativeFinalize", "(J)V", (void*)nativeFinalize },
	{ "nativeDetach", "(J)V", (void*)nativeDetach },
	};

	} // namespace TunerCallback
	} // namespace BroadcastRadio
	} // namespace server

	void register_android_server_broadcastradio_TunerCallback(JavaVM vm, JNIEnv env) {
	using namespace server::BroadcastRadio::TunerCallback;

	gvm = vm;

	auto tunerCbClass = FindClassOrDie(env, "com/android/server/broadcastradio/TunerCallback");
	gjni.TunerCallback.clazz = MakeGlobalRefOrDie(env, tunerCbClass);
	gjni.TunerCallback.nativeContext = GetFieldIDOrDie(env, tunerCbClass, "mNativeContext", "J");
	gjni.TunerCallback.handleHwFailure = GetMethodIDOrDie(env, tunerCbClass, "handleHwFailure", "()V");
	gjni.TunerCallback.onError = GetMethodIDOrDie(env, tunerCbClass, "onError", "(I)V");
	gjni.TunerCallback.onConfigurationChanged = GetMethodIDOrDie(env, tunerCbClass,
	"onConfigurationChanged", "(Landroid/hardware/radio/RadioManager$BandConfig;)V");
	gjni.TunerCallback.onCurrentProgramInfoChanged = GetMethodIDOrDie(env, tunerCbClass,
	"onCurrentProgramInfoChanged", "(Landroid/hardware/radio/RadioManager$ProgramInfo;)V");
	gjni.TunerCallback.onTrafficAnnouncement = GetMethodIDOrDie(env, tunerCbClass,
	"onTrafficAnnouncement", "(Z)V");
	gjni.TunerCallback.onEmergencyAnnouncement = GetMethodIDOrDie(env, tunerCbClass,
	"onEmergencyAnnouncement", "(Z)V");
	gjni.TunerCallback.onAntennaState = GetMethodIDOrDie(env, tunerCbClass,
	"onAntennaState", "(Z)V");
	gjni.TunerCallback.onBackgroundScanAvailabilityChange = GetMethodIDOrDie(env, tunerCbClass,
	"onBackgroundScanAvailabilityChange", "(Z)V");
	gjni.TunerCallback.onBackgroundScanComplete = GetMethodIDOrDie(env, tunerCbClass,
	"onBackgroundScanComplete", "()V");
	gjni.TunerCallback.onProgramListChanged = GetMethodIDOrDie(env, tunerCbClass,
	"onProgramListChanged", "()V");

	auto res = jniRegisterNativeMethods(env, "com/android/server/broadcastradio/TunerCallback",
	gTunerCallbackMethods, NELEM(gTunerCallbackMethods));
	LOG_ALWAYS_FATAL_IF(res < 0, "Unable to register native methods.");
	}

	} // namespace android