services/audioflinger/AudioPolicyService.h

/*
 * Copyright (C) 2009 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.
 */

#ifndef ANDROID_AUDIOPOLICYSERVICE_H
#define ANDROID_AUDIOPOLICYSERVICE_H

#include <media/IAudioPolicyService.h>
#include <media/ToneGenerator.h>
#include <utils/Vector.h>
#include <binder/BinderService.h>

#include <system/audio.h>
#include <hardware/audio_policy.h>
#include <hardware/audio_policy_hal.h>

namespace android {

class String8;

// ----------------------------------------------------------------------------

class AudioPolicyService :
    public BinderService<AudioPolicyService>,
    public BnAudioPolicyService,
//    public AudioPolicyClientInterface,
    public IBinder::DeathRecipient
{
    friend class BinderService<AudioPolicyService>;

public:
    // for BinderService
    static const char *getServiceName() { return "media.audio_policy"; }

    virtual status_t    dump(int fd, const Vector<String16>& args);

    //
    // BnAudioPolicyService (see AudioPolicyInterface for method descriptions)
    //

    virtual status_t setDeviceConnectionState(audio_devices_t device,
                                              audio_policy_dev_state_t state,
                                              const char *device_address);
    virtual audio_policy_dev_state_t getDeviceConnectionState(
                                                                audio_devices_t device,
                                                                const char *device_address);
    virtual status_t setPhoneState(int state);
    virtual status_t setRingerMode(uint32_t mode, uint32_t mask);
    virtual status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
    virtual audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
    virtual audio_io_handle_t getOutput(audio_stream_type_t stream,
                                        uint32_t samplingRate = 0,
                                        uint32_t format = AUDIO_FORMAT_DEFAULT,
                                        uint32_t channels = 0,
                                        audio_policy_output_flags_t flags =
                                            AUDIO_POLICY_OUTPUT_FLAG_INDIRECT);
    virtual status_t startOutput(audio_io_handle_t output,
                                 audio_stream_type_t stream,
                                 int session = 0);
    virtual status_t stopOutput(audio_io_handle_t output,
                                audio_stream_type_t stream,
                                int session = 0);
    virtual void releaseOutput(audio_io_handle_t output);
    virtual audio_io_handle_t getInput(int inputSource,
                                    uint32_t samplingRate = 0,
                                    uint32_t format = AUDIO_FORMAT_DEFAULT,
                                    uint32_t channels = 0,
                                    audio_in_acoustics_t acoustics =
                                            (audio_in_acoustics_t)0);
    virtual status_t startInput(audio_io_handle_t input);
    virtual status_t stopInput(audio_io_handle_t input);
    virtual void releaseInput(audio_io_handle_t input);
    virtual status_t initStreamVolume(audio_stream_type_t stream,
                                      int indexMin,
                                      int indexMax);
    virtual status_t setStreamVolumeIndex(audio_stream_type_t stream, int index);
    virtual status_t getStreamVolumeIndex(audio_stream_type_t stream, int *index);

    virtual uint32_t getStrategyForStream(audio_stream_type_t stream);
    virtual uint32_t getDevicesForStream(audio_stream_type_t stream);

    virtual audio_io_handle_t getOutputForEffect(effect_descriptor_t *desc);
    virtual status_t registerEffect(effect_descriptor_t *desc,
                                    audio_io_handle_t output,
                                    uint32_t strategy,
                                    int session,
                                    int id);
    virtual status_t unregisterEffect(int id);
    virtual bool isStreamActive(int stream, uint32_t inPastMs = 0) const;

    virtual     status_t    onTransact(
                                uint32_t code,
                                const Parcel& data,
                                Parcel* reply,
                                uint32_t flags);

    // IBinder::DeathRecipient
    virtual     void        binderDied(const wp<IBinder>& who);

    //
    // Helpers for the struct audio_policy_service_ops implementation.
    // This is used by the audio policy manager for certain operations that
    // are implemented by the policy service.
    //
    virtual void setParameters(audio_io_handle_t ioHandle,
                               const char *keyValuePairs,
                               int delayMs);

    virtual status_t setStreamVolume(audio_stream_type_t stream,
                                     float volume,
                                     audio_io_handle_t output,
                                     int delayMs = 0);
    virtual status_t startTone(audio_policy_tone_t tone, audio_stream_type_t stream);
    virtual status_t stopTone();
    virtual status_t setVoiceVolume(float volume, int delayMs = 0);

private:
                        AudioPolicyService();
    virtual             ~AudioPolicyService();

            status_t dumpInternals(int fd);

    // Thread used for tone playback and to send audio config commands to audio flinger
    // For tone playback, using a separate thread is necessary to avoid deadlock with mLock because startTone()
    // and stopTone() are normally called with mLock locked and requesting a tone start or stop will cause
    // calls to AudioPolicyService and an attempt to lock mLock.
    // For audio config commands, it is necessary because audio flinger requires that the calling process (user)
    // has permission to modify audio settings.
    class AudioCommandThread : public Thread {
        class AudioCommand;
    public:

        // commands for tone AudioCommand
        enum {
            START_TONE,
            STOP_TONE,
            SET_VOLUME,
            SET_PARAMETERS,
            SET_VOICE_VOLUME
        };

        AudioCommandThread (String8 name);
        virtual             ~AudioCommandThread();

                    status_t    dump(int fd);

        // Thread virtuals
        virtual     void        onFirstRef();
        virtual     bool        threadLoop();

                    void        exit();
                    void        startToneCommand(int type = 0, int stream = 0);
                    void        stopToneCommand();
                    status_t    volumeCommand(int stream, float volume, int output, int delayMs = 0);
                    status_t    parametersCommand(int ioHandle, const char *keyValuePairs, int delayMs = 0);
                    status_t    voiceVolumeCommand(float volume, int delayMs = 0);
                    void        insertCommand_l(AudioCommand *command, int delayMs = 0);

    private:
        // descriptor for requested tone playback event
        class AudioCommand {

        public:
            AudioCommand()
            : mCommand(-1) {}

            void dump(char* buffer, size_t size);

            int mCommand;   // START_TONE, STOP_TONE ...
            nsecs_t mTime;  // time stamp
            Condition mCond; // condition for status return
            status_t mStatus; // command status
            bool mWaitStatus; // true if caller is waiting for status
            void *mParam;     // command parameter (ToneData, VolumeData, ParametersData)
        };

        class ToneData {
        public:
            int mType;      // tone type (START_TONE only)
            int mStream;    // stream type (START_TONE only)
        };

        class VolumeData {
        public:
            int mStream;
            float mVolume;
            int mIO;
        };

        class ParametersData {
        public:
            int mIO;
            String8 mKeyValuePairs;
        };

        class VoiceVolumeData {
        public:
            float mVolume;
        };

        Mutex   mLock;
        Condition mWaitWorkCV;
        Vector <AudioCommand *> mAudioCommands; // list of pending commands
        ToneGenerator *mpToneGenerator;     // the tone generator
        AudioCommand mLastCommand;          // last processed command (used by dump)
        String8 mName;                      // string used by wake lock fo delayed commands
    };

    // Internal dump utilities.
    status_t dumpPermissionDenial(int fd);


    mutable Mutex mLock;    // prevents concurrent access to AudioPolicy manager functions changing
                            // device connection state  or routing
    sp <AudioCommandThread> mAudioCommandThread;    // audio commands thread
    sp <AudioCommandThread> mTonePlaybackThread;     // tone playback thread

    struct audio_policy_device *mpAudioPolicyDev;
    struct audio_policy *mpAudioPolicy;
};

}; // namespace android

#endif // ANDROID_AUDIOPOLICYSERVICE_H