| /* |
| * 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. |
| */ |
| #define ADK_INTERNAL |
| #include "fwk.h" |
| #include "Audio.h" |
| #include "coop.h" |
| |
| #define DEFAULT_AUDIO_SAMPLERATE 44100 |
| |
| static uint32_t sampleRates[AUDIO_MAX_SOURCE]; |
| static uint32_t audioActive; // bitmap of active audio sources |
| |
| static int highestPriAudio(void) |
| { |
| int i; |
| |
| if (audioActive == 0) |
| return -1; |
| |
| return (31 - __builtin_clz(audioActive)); |
| } |
| |
| void audioInit(void) |
| { |
| PMC_EnablePeripheral(ID_PWM); |
| PWMC_ConfigureClocks(0, 0, BOARD_MCK); |
| PWMC_ConfigureChannel(PWM, 0, PWM_CMR_CPRE_MCK, 0, 0); |
| PWMC_ConfigureEventLineMode(PWM, 0, 1); |
| |
| audioSetSample(AUDIO_NULL, DEFAULT_AUDIO_SAMPLERATE); |
| |
| PWMC_EnableChannel(PWM, 0); |
| PMC_EnablePeripheral(ID_DACC); |
| DACC_Initialize(DACC, ID_DACC, 1, 4, 0, 0, BOARD_MCK, 8, DACC_CHANNEL_0, 0, 16 ); |
| DACC_EnableChannel(DACC, DACC_CHANNEL_0); |
| } |
| |
| void audioOn(int source, uint32_t samplerate) |
| { |
| audioActive |= (1 << source); |
| |
| audioSetSample(source, samplerate); |
| } |
| |
| void audioOff(int source) |
| { |
| int resetsample = 0; |
| if (source == highestPriAudio()) |
| resetsample = 1; |
| |
| audioActive &= ~(1 << source); |
| |
| // switch to the new highest priority audio's sample rate |
| int highest = highestPriAudio(); |
| if (resetsample && highest >= 0) { |
| audioSetSample(highest, sampleRates[highest]); |
| } |
| } |
| |
| void audioSetSample(int source, uint32_t samplerate) |
| { |
| sampleRates[source] = samplerate; |
| |
| // if we're not the highest priority audio source, dont set it |
| if (source != highestPriAudio()) |
| return; |
| |
| samplerate = (BOARD_MCK + samplerate - 1) / samplerate; //err on the side of slower audio |
| |
| PWMC_SetPeriod(PWM, 0, samplerate); |
| PWMC_ConfigureComparisonUnit(PWM, 0, (samplerate + 1) >> 1, 1); |
| } |
| |
| void audioAddBuffer(int source, const uint16_t* samples, uint32_t numSamples) |
| { |
| // see if we're the highest priority audio, drop on the floor if we're not |
| if (source != highestPriAudio()) |
| return; |
| |
| while(!DACC_WriteBuffer(DACC, samples, numSamples)) coopYield(); |
| } |
| |
| int audioTryAddBuffer(int source, const uint16_t* samples, uint32_t numSamples) |
| { |
| // see if we're the highest priority audio, drop on the floor if we're not |
| if (source != highestPriAudio()) |
| return 1; // pretend we queued |
| |
| int first_free = (DACC->DACC_TCR == 0) && (DACC->DACC_TNCR == 0); |
| |
| uint32_t res = DACC_WriteBuffer(DACC, samples, numSamples); |
| |
| if (!res) |
| return 0; |
| |
| if (first_free) |
| return 1; |
| else |
| return DACC->DACC_TCR; |
| } |
| |