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/*
* Copyright (C) ST-Ericsson SA 2012
* Copyright (C) 2012 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.
*
* Author: Stefan Ekenberg (stefan.ekenberg@stericsson.com) for ST-Ericsson
*/
#define LOG_TAG "FMRadioSource"
#include <utils/Log.h>
#include <media/stagefright/FMRadioSource.h>
#include <media/AudioSystem.h>
#include <private/media/AudioTrackShared.h>
#include <cutils/compiler.h>
namespace android {
static const int kSampleRate = 48000;
static const audio_format_t kAudioFormat = AUDIO_FORMAT_PCM_16_BIT;
static const audio_channel_mask_t kChannelMask = AUDIO_CHANNEL_IN_STEREO;
static const int kBufferTimeoutMs = 3000;
FMRadioSource::FMRadioSource()
: mInitCheck(NO_INIT),
mStarted(false),
mSessionId(AudioSystem::newAudioSessionId()) {
// get FM Radio RX input
audio_io_handle_t input = AudioSystem::getInput(AUDIO_SOURCE_FM_RX,
kSampleRate,
kAudioFormat,
kChannelMask,
mSessionId);
if (input == 0) {
ALOGE("Could not get audio input for FM Radio source");
mInitCheck = UNKNOWN_ERROR;
return;
}
// get frame count
int frameCount = 0;
status_t status = AudioRecord::getMinFrameCount(&frameCount, kSampleRate,
kAudioFormat, popcount(kChannelMask));
if (status != NO_ERROR) {
mInitCheck = status;
return;
}
// create the IAudioRecord
status = openRecord(frameCount, input);
if (status != NO_ERROR) {
mInitCheck = status;
return;
}
AudioSystem::acquireAudioSessionId(mSessionId);
mInitCheck = OK;
return;
}
FMRadioSource::~FMRadioSource() {
AudioSystem::releaseAudioSessionId(mSessionId);
}
status_t FMRadioSource::initCheck() const {
return mInitCheck;
}
ssize_t FMRadioSource::readAt(off64_t offset, void *data, size_t size) {
Buffer audioBuffer;
if (!mStarted) {
status_t err = mAudioRecord->start(AudioSystem::SYNC_EVENT_NONE, 0);
if (err == OK) {
mStarted = true;
} else {
ALOGE("Failed to start audio source");
return 0;
}
}
// acquire a strong reference on the IAudioRecord and IMemory so that they cannot be destroyed
// while we are accessing the cblk
sp<IAudioRecord> audioRecord = mAudioRecord;
sp<IMemory> iMem = mCblkMemory;
audio_track_cblk_t* cblk = mCblk;
audioBuffer.frameCount = size / cblk->frameSize;
status_t err = obtainBuffer(&audioBuffer);
if (err != NO_ERROR) {
ALOGE("Error obtaining an audio buffer, giving up (err:%d).", err);
return 0;
}
memcpy(data, audioBuffer.data, audioBuffer.size);
mCblk->stepUser(audioBuffer.frameCount);
return audioBuffer.size;
}
status_t FMRadioSource::getSize(off64_t *size) {
*size = 0;
return OK;
}
// -------------------------------------------------------------------------
status_t FMRadioSource::openRecord(int frameCount, audio_io_handle_t input)
{
status_t status;
const sp<IAudioFlinger>& audioFlinger = AudioSystem::get_audio_flinger();
if (audioFlinger == 0) {
return NO_INIT;
}
sp<IAudioRecord> record = audioFlinger->openRecord(getpid(), input,
kSampleRate,
kAudioFormat,
kChannelMask,
frameCount,
IAudioFlinger::TRACK_DEFAULT,
gettid(),
&mSessionId,
&status);
if (record == 0) {
ALOGE("AudioFlinger could not create record track, status: %d", status);
return status;
}
sp<IMemory> cblk = record->getCblk();
if (cblk == 0) {
ALOGE("Could not get control block");
return NO_INIT;
}
mAudioRecord = record;
mCblkMemory = cblk;
mCblk = static_cast<audio_track_cblk_t*>(cblk->pointer());
mCblk->buffers = (char*)mCblk + sizeof(audio_track_cblk_t);
android_atomic_and(~CBLK_DIRECTION_MSK, &mCblk->flags);
return NO_ERROR;
}
status_t FMRadioSource::obtainBuffer(Buffer* audioBuffer)
{
status_t result = NO_ERROR;
uint32_t framesReq = audioBuffer->frameCount;
audioBuffer->frameCount = 0;
audioBuffer->size = 0;
mCblk->lock.lock();
uint32_t framesReady = mCblk->framesReady();
if (framesReady == 0) {
do {
result = mCblk->cv.waitRelative(mCblk->lock, milliseconds(kBufferTimeoutMs));
if (CC_UNLIKELY(result != NO_ERROR)) {
ALOGE("obtainBuffer timed out (is the CPU pegged?) "
"user=%08x, server=%08x", mCblk->user, mCblk->server);
mCblk->lock.unlock();
return TIMED_OUT;
}
framesReady = mCblk->framesReady();
} while (framesReady == 0);
}
mCblk->lock.unlock();
if (framesReq > framesReady) {
framesReq = framesReady;
}
uint32_t u = mCblk->user;
uint32_t bufferEnd = mCblk->userBase + mCblk->frameCount;
if (framesReq > bufferEnd - u) {
framesReq = bufferEnd - u;
}
audioBuffer->frameCount = framesReq;
audioBuffer->size = framesReq * mCblk->frameSize;
audioBuffer->data = (int8_t*)mCblk->buffer(u);
return NO_ERROR;
}
} // namespace android
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