xref: /btstack/platform/embedded/btstack_audio_embedded.c (revision 3faa160f75c1f2da2f28f5c07981475e5ed0ba4e)
1 /*
2  * Copyright (C) 2018 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 #define BTSTACK_FILE__ "btstack_audio_embedded.c"
39 
40 /*
41  *  btstack_audio_embedded.c
42  *
43  *  Implementation of btstack_audio.h using hal_audio.h for embedded run loop
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 // allow to compile all files in embedded folder even if there's no audio support
50 #ifdef HAVE_HAL_AUDIO
51 
52 #include "btstack_debug.h"
53 #include "btstack_audio.h"
54 #include "btstack_run_loop_embedded.h"
55 #include "hal_audio.h"
56 
57 #include <stddef.h>
58 
59 #define DRIVER_POLL_INTERVAL_MS          5
60 
61 // client
62 static void (*playback_callback)(int16_t * buffer, uint16_t num_samples);
63 static void (*recording_callback)(const int16_t * buffer, uint16_t num_samples);
64 
65 // timer to fill output ring buffer
66 static btstack_timer_source_t  driver_timer_sink;
67 static btstack_timer_source_t  driver_timer_source;
68 
69 static volatile unsigned int output_buffer_to_play;
70 static          unsigned int output_buffer_to_fill;
71 static          unsigned int output_buffer_count;
72 static          unsigned int output_buffer_samples;
73 
74 static volatile int       input_buffer_ready;
75 static volatile const int16_t * input_buffer_samples;
76 static volatile uint16_t  input_buffer_num_samples;
77 
78 static int source_active;
79 static int sink_active;
80 
81 // Support for stereo-only audio hal
82 #ifdef HAVE_HAL_AUDIO_SINK_STEREO_ONLY
83 static bool output_duplicate_samples;
84 #endif
85 
86 static void btstack_audio_audio_played(uint8_t buffer_index){
87     output_buffer_to_play = (buffer_index + 1) % output_buffer_count;
88 }
89 
90 static void btstack_audio_audio_recorded(const int16_t * samples, uint16_t num_samples){
91     input_buffer_samples     = samples;
92     input_buffer_num_samples = num_samples;
93     input_buffer_ready       = 1;
94 }
95 
96 static void driver_timer_handler_sink(btstack_timer_source_t * ts){
97 
98     // playback buffer ready to fill
99     if (output_buffer_to_play != output_buffer_to_fill){
100         int16_t * buffer = hal_audio_sink_get_output_buffer(output_buffer_to_fill);
101         (*playback_callback)(buffer, output_buffer_samples);
102 
103 #ifdef HAVE_HAL_AUDIO_SINK_STEREO_ONLY
104         if (output_duplicate_samples){
105             unsigned int i = output_buffer_samples;
106             do {
107                 i--;
108                 int16_t sample = buffer[i];
109                 buffer[2*i + 0] = sample;
110                 buffer[2*i + 1] = sample;
111             } while ( i > 0 );
112         }
113 #endif
114 
115         // next
116         output_buffer_to_fill = (output_buffer_to_fill + 1 ) % output_buffer_count;
117     }
118 
119     // re-set timer
120     btstack_run_loop_set_timer(ts, DRIVER_POLL_INTERVAL_MS);
121     btstack_run_loop_add_timer(ts);
122 }
123 
124 static void driver_timer_handler_source(btstack_timer_source_t * ts){
125     // deliver samples if ready
126     if (input_buffer_ready){
127         (*recording_callback)((const int16_t *)input_buffer_samples, input_buffer_num_samples);
128         input_buffer_ready = 0;
129     }
130 
131     // re-set timer
132     btstack_run_loop_set_timer(ts, DRIVER_POLL_INTERVAL_MS);
133     btstack_run_loop_add_timer(ts);
134 }
135 
136 static int btstack_audio_embedded_sink_init(
137     uint8_t channels,
138     uint32_t samplerate,
139     void (*playback)(int16_t * buffer, uint16_t num_samples)
140 ){
141     btstack_assert(playback != NULL);
142     btstack_assert(channels != 0);
143 
144 #ifdef HAVE_HAL_AUDIO_SINK_STEREO_ONLY
145     // always use stereo from hal, duplicate samples if needed
146     output_duplicate_samples = channels != 2;
147     channels = 2;
148 #endif
149 
150     playback_callback  = playback;
151 
152     hal_audio_sink_init(channels, samplerate, &btstack_audio_audio_played);
153 
154     return 0;
155 }
156 
157 static int btstack_audio_embedded_source_init(
158     uint8_t channels,
159     uint32_t samplerate,
160     void (*recording)(const int16_t * buffer, uint16_t num_samples)
161 ){
162     if (!recording){
163         log_error("No recording callback");
164         return 1;
165     }
166 
167     recording_callback  = recording;
168 
169     hal_audio_source_init(channels, samplerate, &btstack_audio_audio_recorded);
170 
171     return 0;
172 }
173 
174 static void btstack_audio_embedded_sink_set_volume(uint8_t volume){
175     UNUSED(volume);
176 }
177 
178 static void btstack_audio_embedded_source_set_gain(uint8_t gain){
179     UNUSED(gain);
180 }
181 
182 static void btstack_audio_embedded_sink_start_stream(void){
183     output_buffer_count   = hal_audio_sink_get_num_output_buffers();
184     output_buffer_samples = hal_audio_sink_get_num_output_buffer_samples();
185 
186     btstack_assert(output_buffer_samples > 0);
187 
188     // pre-fill HAL buffers
189     uint16_t i;
190     for (i=0;i<output_buffer_count;i++){
191         int16_t * buffer = hal_audio_sink_get_output_buffer(i);
192         (*playback_callback)(buffer, output_buffer_samples);
193     }
194 
195     output_buffer_to_play = 0;
196     output_buffer_to_fill = 0;
197 
198     // start playback
199     hal_audio_sink_start();
200 
201     // start timer
202     btstack_run_loop_set_timer_handler(&driver_timer_sink, &driver_timer_handler_sink);
203     btstack_run_loop_set_timer(&driver_timer_sink, DRIVER_POLL_INTERVAL_MS);
204     btstack_run_loop_add_timer(&driver_timer_sink);
205 
206     // state
207     sink_active = 1;
208 }
209 
210 static void btstack_audio_embedded_source_start_stream(void){
211     // just started, no data ready
212     input_buffer_ready = 0;
213 
214     // start recording
215     hal_audio_source_start();
216 
217     // start timer
218     btstack_run_loop_set_timer_handler(&driver_timer_source, &driver_timer_handler_source);
219     btstack_run_loop_set_timer(&driver_timer_source, DRIVER_POLL_INTERVAL_MS);
220     btstack_run_loop_add_timer(&driver_timer_source);
221 
222     // state
223     source_active = 1;
224 }
225 
226 static void btstack_audio_embedded_sink_stop_stream(void){
227     // stop stream
228     hal_audio_sink_stop();
229     // stop timer
230     btstack_run_loop_remove_timer(&driver_timer_sink);
231     // state
232     sink_active = 0;
233 }
234 
235 static void btstack_audio_embedded_source_stop_stream(void){
236     // stop stream
237     hal_audio_source_stop();
238     // stop timer
239     btstack_run_loop_remove_timer(&driver_timer_source);
240     // state
241     source_active = 0;
242 }
243 
244 static void btstack_audio_embedded_sink_close(void){
245     // stop stream if needed
246     if (sink_active){
247         btstack_audio_embedded_sink_stop_stream();
248     }
249     // close HAL
250     hal_audio_sink_close();
251 }
252 
253 static void btstack_audio_embedded_source_close(void){
254     // stop stream if needed
255     if (source_active){
256         btstack_audio_embedded_source_stop_stream();
257     }
258     // close HAL
259     hal_audio_source_close();
260 }
261 
262 static const btstack_audio_sink_t btstack_audio_embedded_sink = {
263     /* int (*init)(..);*/                                       &btstack_audio_embedded_sink_init,
264     /* void (*set_volume)(uint8_t volume); */                   &btstack_audio_embedded_sink_set_volume,
265     /* void (*start_stream(void));*/                            &btstack_audio_embedded_sink_start_stream,
266     /* void (*stop_stream)(void)  */                            &btstack_audio_embedded_sink_stop_stream,
267     /* void (*close)(void); */                                  &btstack_audio_embedded_sink_close
268 };
269 
270 static const btstack_audio_source_t btstack_audio_embedded_source = {
271     /* int (*init)(..);*/                                       &btstack_audio_embedded_source_init,
272     /* void (*set_gain)(uint8_t gain); */                       &btstack_audio_embedded_source_set_gain,
273     /* void (*start_stream(void));*/                            &btstack_audio_embedded_source_start_stream,
274     /* void (*stop_stream)(void)  */                            &btstack_audio_embedded_source_stop_stream,
275     /* void (*close)(void); */                                  &btstack_audio_embedded_source_close
276 };
277 
278 const btstack_audio_sink_t * btstack_audio_embedded_sink_get_instance(void){
279     return &btstack_audio_embedded_sink;
280 }
281 
282 const btstack_audio_source_t * btstack_audio_embedded_source_get_instance(void){
283     return &btstack_audio_embedded_source;
284 }
285 
286 #endif
287