Merge "aaudio: prevent very short sleeps in callback thread" into tm-dev

                break;

            case AAUDIO_STREAM_STATE_STARTED:

            {

                // Sleep until the readCounter catches up and we only have

                // the getBufferSize() frames of data sitting in the buffer.

                int64_t nextReadPosition = mAudioEndpoint->getDataWriteCounter() - getBufferSize();

                wakeTime = mClockModel.convertPositionToTime(nextReadPosition);

                // Calculate when there will be room available to write to the buffer.

                // If the appBufferSize is smaller than the endpointBufferSize then

                // we will have room to write data beyond the appBufferSize.

                // That is a technique used to reduce glitches without adding latency.

                const int32_t appBufferSize = getBufferSize();

                // The endpoint buffer size is set to the maximum that can be written.

                // If we use it then we must carve out some room to write data when we wake up.

                const int32_t endBufferSize = mAudioEndpoint->getBufferSizeInFrames()

                        - getFramesPerBurst();

                const int32_t bestBufferSize = std::min(appBufferSize, endBufferSize);

                int64_t targetReadPosition = mAudioEndpoint->getDataWriteCounter() - bestBufferSize;

                wakeTime = mClockModel.convertPositionToTime(targetReadPosition);

            }

                break;

            default:

int32_t AAudioProperty_getMinimumSleepMicros() {

    const int32_t minMicros = 1; // arbitrary

    // Higher values can increase latency for moderate workloads.

    const int32_t defaultMicros = 1; // arbitrary

    // Short values can cause the CPU to short cycle if there is a bug in

    // calculating the wakeup times.

    const int32_t defaultMicros = 100; // arbitrary

    const int32_t maxMicros = 200; // arbitrary

    int32_t prop = property_get_int32(AAUDIO_PROP_MINIMUM_SLEEP_USEC, defaultMicros);

    if (prop < minMicros) {