1/* AudioUtil.h
2 *
3 * Copyright (C) 2012 The Android Open Source Project
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18#ifndef ALSA_SOUND_AUDIO_UTIL_H
19#define ALSA_SOUND_AUDIO_UTIL_H
20
21#define BIT(nr)     (1UL << (nr))
22#define MAX_EDID_BLOCKS 10
23#define MAX_SHORT_AUDIO_DESC_CNT        30
24#define MIN_AUDIO_DESC_LENGTH           3
25#define MIN_SPKR_ALLOCATION_DATA_LENGTH 3
26
27typedef enum EDID_AUDIO_FORMAT_ID {
28    LPCM = 1,
29    AC3,
30    MPEG1,
31    MP3,
32    MPEG2_MULTI_CHANNEL,
33    AAC,
34    DTS,
35    ATRAC,
36    SACD,
37    DOLBY_DIGITAL_PLUS,
38    DTS_HD,
39    MAT,
40    DST,
41    WMA_PRO
42} EDID_AUDIO_FORMAT_ID;
43
44typedef struct EDID_AUDIO_BLOCK_INFO {
45    EDID_AUDIO_FORMAT_ID nFormatId;
46    int nSamplingFreq;
47    int nBitsPerSample;
48    int nChannels;
49} EDID_AUDIO_BLOCK_INFO;
50
51typedef struct EDID_AUDIO_INFO {
52    int nAudioBlocks;
53    unsigned char nSpeakerAllocation[MIN_SPKR_ALLOCATION_DATA_LENGTH];
54    EDID_AUDIO_BLOCK_INFO AudioBlocksArray[MAX_EDID_BLOCKS];
55} EDID_AUDIO_INFO;
56
57class AudioUtil {
58public:
59
60    //Parses EDID audio block when if HDMI is connected to determine audio sink capabilities.
61    static bool getHDMIAudioSinkCaps(EDID_AUDIO_INFO*);
62
63private:
64    static int printFormatFromEDID(unsigned char format);
65    static int getSamplingFrequencyFromEDID(unsigned char byte);
66    static int getBitsPerSampleFromEDID(unsigned char byte,
67        unsigned char format);
68    static bool getSpeakerAllocation(EDID_AUDIO_INFO* pInfo);
69};
70
71#endif /* ALSA_SOUND_AUDIO_UTIL_H */
72