1 /* 2 * Copyright (C) 2017 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 /** 39 * @title Audio Interface 40 * 41 * Abstraction layer for 16-bit audio playback and recording within BTstack. 42 * 43 * Most embedded implementations, e.g. the one for ESP32, use a single I2S interface which 44 * requires that the sample rate is the same for sink and source roles 45 */ 46 47 #ifndef BTSTACK_AUDIO_H 48 #define BTSTACK_AUDIO_H 49 50 #include <stdint.h> 51 52 #if defined __cplusplus 53 extern "C" { 54 #endif 55 56 /* API_START */ 57 58 typedef struct { 59 60 /** 61 * @brief Setup audio codec for specified samplerate and number of channels 62 * @param Channels (1=mono, 2=stereo) 63 * @param Sample rate 64 * @param Playback callback 65 * @return 1 on success 66 */ 67 int (*init)(uint8_t channels, 68 uint32_t samplerate, 69 void (*playback) (int16_t * buffer, uint16_t num_samples)); 70 71 /** 72 * @brief Set volume 73 * @param Volume 0..127 74 */ 75 void (*set_volume)(uint8_t volume); 76 77 /** 78 * @brief Start stream 79 */ 80 void (*start_stream)(void); 81 82 /** 83 * @brief Stop stream 84 */ 85 void (*stop_stream)(void); 86 87 /** 88 * @brief Close audio codec 89 */ 90 void (*close)(void); 91 92 } btstack_audio_sink_t; 93 94 95 typedef struct { 96 97 /** 98 * @brief Setup audio codec for specified samplerate and number of channels 99 * @param Channels (1=mono, 2=stereo) 100 * @param Sample rate 101 * @param Recording callback 102 * @return 1 on success 103 */ 104 int (*init)(uint8_t channels, 105 uint32_t samplerate, 106 void (*recording)(const int16_t * buffer, uint16_t num_samples)); 107 108 /** 109 * @brief Set Gain 110 * @param Gain 0..127 111 */ 112 void (*set_gain)(uint8_t gain); 113 114 /** 115 * @brief Start stream 116 */ 117 void (*start_stream)(void); 118 119 /** 120 * @brief Stop stream 121 */ 122 void (*stop_stream)(void); 123 124 /** 125 * @brief Close audio codec 126 */ 127 void (*close)(void); 128 129 } btstack_audio_source_t; 130 131 132 /** 133 * @brief Get BTstack Audio Sink Instance 134 * @return btstack_audio_sink implementation 135 */ 136 const btstack_audio_sink_t * btstack_audio_sink_get_instance(void); 137 138 /** 139 * @brief Get BTstack Audio Source Instance 140 * @return btstack_audio_source implementation 141 */ 142 const btstack_audio_source_t * btstack_audio_source_get_instance(void); 143 144 145 /** 146 * @brief Get BTstack Audio Sink Instance 147 * @param btstack_audio_sink implementation 148 */ 149 void btstack_audio_sink_set_instance(const btstack_audio_sink_t * audio_sink_impl); 150 151 /** 152 * @brief Get BTstack Audio Source Instance 153 * @param btstack_audio_source implementation 154 */ 155 void btstack_audio_source_set_instance(const btstack_audio_source_t * audio_source_impl); 156 157 158 // common implementations 159 const btstack_audio_sink_t * btstack_audio_portaudio_sink_get_instance(void); 160 const btstack_audio_source_t * btstack_audio_portaudio_source_get_instance(void); 161 162 const btstack_audio_sink_t * btstack_audio_embedded_sink_get_instance(void); 163 const btstack_audio_source_t * btstack_audio_embedded_source_get_instance(void); 164 165 const btstack_audio_sink_t * btstack_audio_esp32_sink_get_instance(void); 166 const btstack_audio_source_t * btstack_audio_esp32_source_get_instance(void); 167 168 /* API_END */ 169 170 #if defined __cplusplus 171 } 172 #endif 173 174 #endif 175