xref: /btstack/platform/embedded/hal_audio.h (revision 630ffdd469bbec3276322f46b93e6cfdfcb21c27)
1 /*
2  * Copyright (C) 2018 BlueKitchen GmbH
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20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
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37 
38 #ifndef __HAL_AUDIO_H
39 #define __HAL_AUDIO_H
40 
41 #include <stdint.h>
42 
43 /*
44  *  hal_audio.h
45  *
46  *  Hardware abstraction layer that provides circular audio playback and recording
47  *
48  *  Assumptions:
49  *  - num buffers n >= 2
50  *  - after start, buffers are played in sequence 0, 1, ... , n-1, 0, 1, .. , n-1, ...
51  *  - after a buffer is played, the callback is called with tbe index of the played buffer
52  */
53 
54 /**
55  * @brief Setup audio codec for specified samplerate and number channels
56  * @param Channels
57  * @param Sample rate
58  * @param Buffer played callback
59  * @param Buffer recorded callback (use NULL if no recording)
60  */
61 void hal_audio_init(uint8_t channels,
62                     uint32_t sample_rate,
63                     void (*buffer_played_callback)  (uint8_t buffer_index),
64                     void (*buffer_recorded_callback)(const int16_t * buffer, uint16_t num_samples));
65 
66 /**
67  * @brief Get number of output buffers in HAL
68  * @returns num buffers
69  */
70 uint16_t hal_audio_get_num_output_buffers(void);
71 
72 /**
73  * @brief Get size of single output buffer in HAL
74  * @returns buffer size
75  */
76 uint16_t hal_audio_get_num_output_buffer_samples(void);
77 
78 /**
79  * @brief Gey output buffer
80  * @param buffer index
81  * @returns buffer
82  */
83 int16_t * hal_audio_get_output_buffer(uint8_t buffer_index);
84 
85 /**
86  * @brief Start stream
87  */
88 void hal_audio_start(void);
89 
90 /**
91  * @brief Close audio codec
92  */
93 void hal_audio_close(void);
94 
95 #endif
96