xref: /btstack/src/classic/hfp.c (revision 15b7a1173e37f598e7c568d159468e77de545cae)
1 /*
2  * Copyright (C) 2014 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 MATTHIAS
24  * RINGWALD 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__ "hfp.c"
39 
40 
41 #include "btstack_config.h"
42 
43 #include <stdint.h>
44 #include <stdio.h>
45 #include <string.h>
46 #include <inttypes.h>
47 
48 #include "bluetooth_sdp.h"
49 #include "btstack_debug.h"
50 #include "btstack_event.h"
51 #include "btstack_memory.h"
52 #include "btstack_run_loop.h"
53 #include "classic/sdp_client_rfcomm.h"
54 #include "classic/sdp_server.h"
55 #include "classic/sdp_util.h"
56 #include "classic/sdp_client.h"
57 #include "hci.h"
58 #include "hci_cmd.h"
59 #include "hci_dump.h"
60 
61 #if defined(ENABLE_CC256X_ASSISTED_HFP) && !defined(ENABLE_SCO_OVER_PCM)
62 #error "Assisted HFP is only possible over PCM/I2S. Please add define: ENABLE_SCO_OVER_PCM"
63 #endif
64 
65 #if defined(ENABLE_BCM_PCM_WBS) && !defined(ENABLE_SCO_OVER_PCM)
66 #error "WBS for PCM is only possible over PCM/I2S. Please add define: ENABLE_SCO_OVER_PCM"
67 #endif
68 
69 #define HFP_HF_FEATURES_SIZE 10
70 #define HFP_AG_FEATURES_SIZE 12
71 
72 typedef struct {
73     hfp_role_t local_role;
74     bd_addr_t  remote_address;
75 } hfp_sdp_query_context_t;
76 
77 // globals
78 
79 static btstack_linked_list_t hfp_connections ;
80 
81 static btstack_packet_handler_t hfp_hf_callback;
82 static btstack_packet_handler_t hfp_ag_callback;
83 
84 static btstack_packet_handler_t hfp_hf_rfcomm_packet_handler;
85 static btstack_packet_handler_t hfp_ag_rfcomm_packet_handler;
86 
87 static uint16_t hfp_allowed_sco_packet_types;
88 static hfp_connection_t * hfp_sco_establishment_active;
89 
90 static hfp_sdp_query_context_t                 hfp_sdp_query_context;
91 static btstack_context_callback_registration_t hfp_sdp_query_request;
92 
93 
94 
95 
96 
97 
98 // prototypes
99 static hfp_link_settings_t hfp_next_link_setting_for_connection(hfp_link_settings_t current_setting, hfp_connection_t * hfp_connection, uint8_t eSCO_S4_supported);
100 static void parse_sequence(hfp_connection_t * context);
101 
102 static const char * hfp_hf_features[] = {
103         "EC and/or NR function",
104         "Three-way calling",
105         "CLI presentation capability",
106         "Voice recognition activation",
107         "Remote volume control",
108 
109         "Enhanced call status",
110         "Enhanced call control",
111 
112         "Codec negotiation",
113 
114         "HF Indicators",
115         "eSCO S4 (and T2) Settings Supported",
116         "Reserved for future definition"
117 };
118 
119 static const char * hfp_ag_features[] = {
120         "Three-way calling",
121         "EC and/or NR function",
122         "Voice recognition function",
123         "In-band ring tone capability",
124         "Attach a number to a voice tag",
125         "Ability to reject a call",
126         "Enhanced call status",
127         "Enhanced call control",
128         "Extended Error Result Codes",
129         "Codec negotiation",
130         "HF Indicators",
131         "eSCO S4 (and T2) Settings Supported",
132         "Reserved for future definition"
133 };
134 
135 static const char * hfp_enhanced_call_dir[] = {
136         "outgoing",
137         "incoming"
138 };
139 
140 static const char * hfp_enhanced_call_status[] = {
141         "active",
142         "held",
143         "outgoing dialing",
144         "outgoing alerting",
145         "incoming",
146         "incoming waiting",
147         "call held by response and hold"
148 };
149 
150 static const char * hfp_enhanced_call_mode[] = {
151         "voice",
152         "data",
153         "fax"
154 };
155 
156 static const char * hfp_enhanced_call_mpty[] = {
157         "not a conference call",
158         "conference call"
159 };
160 
161 const char * hfp_enhanced_call_dir2str(uint16_t index){
162     if (index <= HFP_ENHANCED_CALL_DIR_INCOMING) return hfp_enhanced_call_dir[index];
163     return "not defined";
164 }
165 
166 const char * hfp_enhanced_call_status2str(uint16_t index){
167     if (index <= HFP_ENHANCED_CALL_STATUS_CALL_HELD_BY_RESPONSE_AND_HOLD) return hfp_enhanced_call_status[index];
168     return "not defined";
169 }
170 
171 const char * hfp_enhanced_call_mode2str(uint16_t index){
172     if (index <= HFP_ENHANCED_CALL_MODE_FAX) return hfp_enhanced_call_mode[index];
173     return "not defined";
174 }
175 
176 const char * hfp_enhanced_call_mpty2str(uint16_t index){
177     if (index <= HFP_ENHANCED_CALL_MPTY_CONFERENCE_CALL) return hfp_enhanced_call_mpty[index];
178     return "not defined";
179 }
180 
181 static uint16_t hfp_parse_indicator_index(hfp_connection_t * hfp_connection){
182     uint16_t index = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
183 
184     if (index > HFP_MAX_NUM_INDICATORS){
185         log_info("ignoring invalid indicator index bigger then HFP_MAX_NUM_INDICATORS");
186         return HFP_MAX_NUM_INDICATORS - 1;
187     }
188 
189     // indicator index enumeration starts with 1, we substract 1 to store in array with starting index 0
190     if (index > 0){
191         index -= 1;
192     } else {
193         log_info("ignoring invalid indicator index 0");
194         return 0;
195     }
196     return index;
197 }
198 
199 static void hfp_next_indicators_index(hfp_connection_t * hfp_connection){
200     if (hfp_connection->parser_item_index < HFP_MAX_NUM_INDICATORS - 1){
201         hfp_connection->parser_item_index++;
202     } else {
203         log_info("Ignoring additional indicator");
204     }
205 }
206 
207 static void hfp_next_codec_index(hfp_connection_t * hfp_connection){
208     if (hfp_connection->parser_item_index < HFP_MAX_NUM_CODECS - 1){
209         hfp_connection->parser_item_index++;
210     } else {
211         log_info("Ignoring additional codec index");
212     }
213 }
214 
215 static void hfp_next_remote_call_services_index(hfp_connection_t * hfp_connection){
216     if (hfp_connection->remote_call_services_index < HFP_MAX_NUM_CALL_SERVICES - 1){
217         hfp_connection->remote_call_services_index++;
218     } else {
219         log_info("Ignoring additional remote_call_services");
220     }
221 }
222 
223 const char * hfp_hf_feature(int index){
224     if (index > HFP_HF_FEATURES_SIZE){
225         return hfp_hf_features[HFP_HF_FEATURES_SIZE];
226     }
227     return hfp_hf_features[index];
228 }
229 
230 const char * hfp_ag_feature(int index){
231     if (index > HFP_AG_FEATURES_SIZE){
232         return hfp_ag_features[HFP_AG_FEATURES_SIZE];
233     }
234     return hfp_ag_features[index];
235 }
236 
237 int send_str_over_rfcomm(uint16_t cid, char * command){
238     if (!rfcomm_can_send_packet_now(cid)) return 1;
239     log_info("HFP_TX %s", command);
240     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
241     if (err){
242         log_error("rfcomm_send -> error 0x%02x \n", err);
243     }
244 #ifdef ENABLE_HFP_AT_MESSAGES
245     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_rfcomm_cid(cid);
246     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_SENT, command);
247 #endif
248     return 1;
249 }
250 
251 int hfp_supports_codec(uint8_t codec, int codecs_nr, uint8_t * codecs){
252 
253     // mSBC requires support for eSCO connections
254     if ((codec == HFP_CODEC_MSBC) && !hci_extended_sco_link_supported()) return 0;
255 
256     int i;
257     for (i = 0; i < codecs_nr; i++){
258         if (codecs[i] != codec) continue;
259         return 1;
260     }
261     return 0;
262 }
263 
264 void hfp_hf_drop_mSBC_if_eSCO_not_supported(uint8_t * codecs, uint8_t * codecs_nr){
265     if (hci_extended_sco_link_supported()) return;
266     uint8_t tmp_codecs[HFP_MAX_NUM_CODECS];
267     int i;
268     int tmp_codec_nr = 0;
269     for (i=0; i < *codecs_nr; i++){
270         if (codecs[i] == HFP_CODEC_MSBC) continue;
271         tmp_codecs[tmp_codec_nr++] = codecs[i];
272     }
273     *codecs_nr = tmp_codec_nr;
274     (void)memcpy(codecs, tmp_codecs, tmp_codec_nr);
275 }
276 
277 // UTILS
278 int get_bit(uint16_t bitmap, int position){
279     return (bitmap >> position) & 1;
280 }
281 
282 int store_bit(uint32_t bitmap, int position, uint8_t value){
283     if (value){
284         bitmap |= 1 << position;
285     } else {
286         bitmap &= ~ (1 << position);
287     }
288     return bitmap;
289 }
290 
291 int join(char * buffer, int buffer_size, uint8_t * values, int values_nr){
292     if (buffer_size < (values_nr * 3)) return 0;
293     int i;
294     int offset = 0;
295     for (i = 0; i < (values_nr-1); i++) {
296       offset += snprintf(buffer+offset, buffer_size-offset, "%d,", values[i]); // puts string into buffer
297     }
298     if (i<values_nr){
299         offset += snprintf(buffer+offset, buffer_size-offset, "%d", values[i]);
300     }
301     return offset;
302 }
303 
304 int join_bitmap(char * buffer, int buffer_size, uint32_t values, int values_nr){
305     if (buffer_size < (values_nr * 3)) return 0;
306 
307     int i;
308     int offset = 0;
309     for (i = 0; i < (values_nr-1); i++) {
310       offset += snprintf(buffer+offset, buffer_size-offset, "%d,", get_bit(values,i)); // puts string into buffer
311     }
312 
313     if (i<values_nr){
314         offset += snprintf(buffer+offset, buffer_size-offset, "%d", get_bit(values,i));
315     }
316     return offset;
317 }
318 
319 static void hfp_emit_event_for_context(hfp_connection_t * hfp_connection, uint8_t * packet, uint16_t size){
320     if (!hfp_connection) return;
321     btstack_packet_handler_t callback = NULL;
322     switch (hfp_connection->local_role){
323         case HFP_ROLE_HF:
324             callback = hfp_hf_callback;
325             break;
326         case HFP_ROLE_AG:
327             callback = hfp_ag_callback;
328             break;
329         default:
330             return;
331     }
332     (*callback)(HCI_EVENT_PACKET, 0, packet, size);
333 }
334 
335 void hfp_emit_simple_event(hfp_connection_t * hfp_connection, uint8_t event_subtype){
336     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
337     uint8_t event[5];
338     event[0] = HCI_EVENT_HFP_META;
339     event[1] = sizeof(event) - 2;
340     event[2] = event_subtype;
341     little_endian_store_16(event, 3, acl_handle);
342     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
343 }
344 
345 void hfp_emit_event(hfp_connection_t * hfp_connection, uint8_t event_subtype, uint8_t value){
346     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
347     uint8_t event[6];
348     event[0] = HCI_EVENT_HFP_META;
349     event[1] = sizeof(event) - 2;
350     event[2] = event_subtype;
351     little_endian_store_16(event, 3, acl_handle);
352     event[5] = value; // status 0 == OK
353     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
354 }
355 
356 void hfp_emit_voice_recognition_enabled(hfp_connection_t * hfp_connection, uint8_t status){
357     btstack_assert(hfp_connection != NULL);
358 
359     uint8_t event[7];
360     event[0] = HCI_EVENT_HFP_META;
361     event[1] = sizeof(event) - 2;
362     event[2] = HFP_SUBEVENT_VOICE_RECOGNITION_ACTIVATED;
363 
364     little_endian_store_16(event, 3, hfp_connection->acl_handle);
365     event[5] = status; // 0:success
366     event[6] = hfp_connection->enhanced_voice_recognition_enabled ? 1 : 0;
367     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
368 }
369 
370 void hfp_emit_voice_recognition_disabled(hfp_connection_t * hfp_connection, uint8_t status){
371     btstack_assert(hfp_connection != NULL);
372 
373     uint8_t event[6];
374     event[0] = HCI_EVENT_HFP_META;
375     event[1] = sizeof(event) - 2;
376     event[2] = HFP_SUBEVENT_VOICE_RECOGNITION_DEACTIVATED;
377 
378     little_endian_store_16(event, 3, hfp_connection->acl_handle);
379     event[5] = status; // 0:success
380     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
381 }
382 
383 void hfp_emit_enhanced_voice_recognition_hf_ready_for_audio_event(hfp_connection_t * hfp_connection, uint8_t status){
384     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
385 
386     uint8_t event[6];
387     event[0] = HCI_EVENT_HFP_META;
388     event[1] = sizeof(event) - 2;
389     event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_HF_READY_FOR_AUDIO;
390     little_endian_store_16(event, 3, acl_handle);
391     event[5] = status;
392     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
393 }
394 
395 void hfp_emit_enhanced_voice_recognition_state_event(hfp_connection_t * hfp_connection, uint8_t status){
396     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
397 
398     uint8_t event[6];
399     event[0] = HCI_EVENT_HFP_META;
400     event[1] = sizeof(event) - 2;
401     switch (hfp_connection->ag_vra_state){
402         case HFP_VOICE_RECOGNITION_STATE_AG_READY_TO_ACCEPT_AUDIO_INPUT:
403             event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_AG_READY_TO_ACCEPT_AUDIO_INPUT;
404             break;
405         case HFP_VOICE_RECOGNITION_STATE_AG_IS_STARTING_SOUND:
406             event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_AG_IS_STARTING_SOUND;
407             break;
408         case HFP_VOICE_RECOGNITION_STATE_AG_IS_PROCESSING_AUDIO_INPUT:
409             event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_AG_IS_PROCESSING_AUDIO_INPUT;
410             break;
411         default:
412             btstack_unreachable();
413             break;
414     }
415 
416     little_endian_store_16(event, 3, acl_handle);
417     event[5] = status;
418     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
419 }
420 
421 void hfp_emit_slc_connection_event(hfp_connection_t * hfp_connection, uint8_t status, hci_con_handle_t con_handle, bd_addr_t addr){
422     btstack_assert(hfp_connection != NULL);
423     uint8_t event[12];
424     int pos = 0;
425     event[pos++] = HCI_EVENT_HFP_META;
426     event[pos++] = sizeof(event) - 2;
427     event[pos++] = HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
428     little_endian_store_16(event, pos, con_handle);
429     pos += 2;
430     event[pos++] = status; // status 0 == OK
431     reverse_bd_addr(addr,&event[pos]);
432     pos += 6;
433     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
434 }
435 
436 static void hfp_emit_audio_connection_released(hfp_connection_t * hfp_connection, hci_con_handle_t sco_handle){
437     btstack_assert(hfp_connection != NULL);
438     uint8_t event[7];
439     int pos = 0;
440     event[pos++] = HCI_EVENT_HFP_META;
441     event[pos++] = sizeof(event) - 2;
442     event[pos++] = HFP_SUBEVENT_AUDIO_CONNECTION_RELEASED;
443     little_endian_store_16(event, pos, hfp_connection->acl_handle);
444     pos += 2;
445     little_endian_store_16(event, pos, sco_handle);
446     pos += 2;
447     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
448 }
449 
450 void hfp_emit_sco_event(hfp_connection_t * hfp_connection, uint8_t status, hci_con_handle_t sco_handle, bd_addr_t addr, uint8_t  negotiated_codec){
451     btstack_assert(hfp_connection != NULL);
452     uint8_t event[15];
453     int pos = 0;
454     event[pos++] = HCI_EVENT_HFP_META;
455     event[pos++] = sizeof(event) - 2;
456     event[pos++] = HFP_SUBEVENT_AUDIO_CONNECTION_ESTABLISHED;
457     little_endian_store_16(event, pos, hfp_connection->acl_handle);
458     pos += 2;
459     event[pos++] = status; // status 0 == OK
460     little_endian_store_16(event, pos, sco_handle);
461     pos += 2;
462     reverse_bd_addr(addr,&event[pos]);
463     pos += 6;
464     event[pos++] = negotiated_codec;
465     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
466 }
467 
468 void hfp_emit_string_event(hfp_connection_t * hfp_connection, uint8_t event_subtype, const char * value){
469     btstack_assert(hfp_connection != NULL);
470 #ifdef ENABLE_HFP_AT_MESSAGES
471     uint8_t event[256];
472 #else
473     uint8_t event[40];
474 #endif
475     event[0] = HCI_EVENT_HFP_META;
476     event[1] = sizeof(event) - 2;
477     event[2] = event_subtype;
478     little_endian_store_16(event, 3, hfp_connection->acl_handle);
479     uint16_t size = btstack_min(strlen(value), sizeof(event) - 6);
480     strncpy((char*)&event[5], value, size);
481     event[5 + size] = 0;
482     hfp_emit_event_for_context(hfp_connection, event, sizeof(event));
483 }
484 
485 btstack_linked_list_t * hfp_get_connections(void){
486     return (btstack_linked_list_t *) &hfp_connections;
487 }
488 
489 hfp_connection_t * get_hfp_connection_context_for_rfcomm_cid(uint16_t cid){
490     btstack_linked_list_iterator_t it;
491     btstack_linked_list_iterator_init(&it, hfp_get_connections());
492     while (btstack_linked_list_iterator_has_next(&it)){
493         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
494         if (hfp_connection->rfcomm_cid == cid){
495             return hfp_connection;
496         }
497     }
498     return NULL;
499 }
500 
501 hfp_connection_t * get_hfp_connection_context_for_bd_addr(bd_addr_t bd_addr, hfp_role_t hfp_role){
502     btstack_linked_list_iterator_t it;
503     btstack_linked_list_iterator_init(&it, hfp_get_connections());
504     while (btstack_linked_list_iterator_has_next(&it)){
505         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
506         if ((memcmp(hfp_connection->remote_addr, bd_addr, 6) == 0) && (hfp_connection->local_role == hfp_role)) {
507             return hfp_connection;
508         }
509     }
510     return NULL;
511 }
512 
513 hfp_connection_t * get_hfp_connection_context_for_sco_handle(uint16_t handle, hfp_role_t hfp_role){
514     btstack_linked_list_iterator_t it;
515     btstack_linked_list_iterator_init(&it, hfp_get_connections());
516     while (btstack_linked_list_iterator_has_next(&it)){
517         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
518         if ((hfp_connection->sco_handle == handle) && (hfp_connection->local_role == hfp_role)){
519             return hfp_connection;
520         }
521     }
522     return NULL;
523 }
524 
525 hfp_connection_t * get_hfp_connection_context_for_acl_handle(uint16_t handle, hfp_role_t hfp_role){
526     btstack_linked_list_iterator_t it;
527     btstack_linked_list_iterator_init(&it, hfp_get_connections());
528     while (btstack_linked_list_iterator_has_next(&it)){
529         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
530         if ((hfp_connection->acl_handle == handle) && (hfp_connection->local_role == hfp_role)){
531             return hfp_connection;
532         }
533     }
534     return NULL;
535 }
536 
537 
538 static void hfp_reset_voice_recognition(hfp_connection_t * hfp_connection){
539     btstack_assert(hfp_connection != NULL);
540     hfp_voice_recognition_activation_status_t current_vra_state = hfp_connection->vra_state;
541     hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_OFF;
542 
543     if (current_vra_state != HFP_VRA_VOICE_RECOGNITION_OFF){
544         hfp_emit_voice_recognition_disabled(hfp_connection, ERROR_CODE_SUCCESS);
545     } else if (hfp_connection->vra_state_requested != HFP_VRA_VOICE_RECOGNITION_OFF){
546         hfp_emit_voice_recognition_disabled(hfp_connection, ERROR_CODE_SUCCESS);
547     }
548 
549     hfp_connection->vra_state_requested = HFP_VRA_VOICE_RECOGNITION_OFF;
550     hfp_connection->activate_voice_recognition = false;
551     hfp_connection->deactivate_voice_recognition = false;
552     hfp_connection->enhanced_voice_recognition_enabled = false;
553     hfp_connection->ag_vra_status = 0;
554     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
555 }
556 
557 void hfp_reset_context_flags(hfp_connection_t * hfp_connection){
558     if (!hfp_connection) return;
559     hfp_connection->ok_pending = 0;
560     hfp_connection->send_error = 0;
561 
562     hfp_connection->found_equal_sign = false;
563 
564     hfp_connection->change_status_update_for_individual_ag_indicators = 0;
565     hfp_connection->operator_name_changed = 0;
566 
567     hfp_connection->enable_extended_audio_gateway_error_report = 0;
568     hfp_connection->extended_audio_gateway_error = 0;
569 
570     // establish codecs hfp_connection
571     hfp_connection->suggested_codec = 0;
572     hfp_connection->negotiated_codec = 0;
573     hfp_connection->codec_confirmed = 0;
574 
575     hfp_connection->establish_audio_connection = 0;
576     hfp_connection->call_waiting_notification_enabled = 0;
577     hfp_connection->command = HFP_CMD_NONE;
578     hfp_connection->enable_status_update_for_ag_indicators = 0xFF;
579     hfp_reset_voice_recognition(hfp_connection);
580 }
581 
582 static hfp_connection_t * create_hfp_connection_context(void){
583     hfp_connection_t * hfp_connection = btstack_memory_hfp_connection_get();
584     if (!hfp_connection) return NULL;
585 
586     hfp_connection->state = HFP_IDLE;
587     hfp_connection->call_state = HFP_CALL_IDLE;
588     hfp_connection->codecs_state = HFP_CODECS_IDLE;
589 
590     hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
591     hfp_connection->command = HFP_CMD_NONE;
592 
593     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
594     hfp_connection->sco_handle = HCI_CON_HANDLE_INVALID;
595 
596     hfp_reset_context_flags(hfp_connection);
597 
598     btstack_linked_list_add(&hfp_connections, (btstack_linked_item_t*)hfp_connection);
599     return hfp_connection;
600 }
601 
602 void hfp_finalize_connection_context(hfp_connection_t * hfp_connection){
603     btstack_linked_list_remove(&hfp_connections, (btstack_linked_item_t*) hfp_connection);
604     btstack_memory_hfp_connection_free(hfp_connection);
605 }
606 
607 static hfp_connection_t * hfp_create_connection(bd_addr_t bd_addr, hfp_role_t local_role){
608     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_bd_addr(bd_addr, local_role);
609     if (hfp_connection) return  hfp_connection;
610     hfp_connection = create_hfp_connection_context();
611     (void)memcpy(hfp_connection->remote_addr, bd_addr, 6);
612     hfp_connection->local_role = local_role;
613     log_info("Create HFP context %p: role %u, addr %s", hfp_connection, local_role, bd_addr_to_str(bd_addr));
614 
615     return hfp_connection;
616 }
617 
618 /* @param network.
619  * 0 == no ability to reject a call.
620  * 1 == ability to reject a call.
621  */
622 
623 /* @param suported_features
624  * HF bit 0: EC and/or NR function (yes/no, 1 = yes, 0 = no)
625  * HF bit 1: Call waiting or three-way calling(yes/no, 1 = yes, 0 = no)
626  * HF bit 2: CLI presentation capability (yes/no, 1 = yes, 0 = no)
627  * HF bit 3: Voice recognition activation (yes/no, 1= yes, 0 = no)
628  * HF bit 4: Remote volume control (yes/no, 1 = yes, 0 = no)
629  * HF bit 5: Wide band speech (yes/no, 1 = yes, 0 = no)
630  */
631  /* Bit position:
632  * AG bit 0: Three-way calling (yes/no, 1 = yes, 0 = no)
633  * AG bit 1: EC and/or NR function (yes/no, 1 = yes, 0 = no)
634  * AG bit 2: Voice recognition function (yes/no, 1 = yes, 0 = no)
635  * AG bit 3: In-band ring tone capability (yes/no, 1 = yes, 0 = no)
636  * AG bit 4: Attach a phone number to a voice tag (yes/no, 1 = yes, 0 = no)
637  * AG bit 5: Wide band speech (yes/no, 1 = yes, 0 = no)
638  */
639 
640 void hfp_create_sdp_record(uint8_t * service, uint32_t service_record_handle, uint16_t service_uuid, int rfcomm_channel_nr, const char * name){
641     uint8_t* attribute;
642     de_create_sequence(service);
643 
644     // 0x0000 "Service Record Handle"
645     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
646     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
647 
648     // 0x0001 "Service Class ID List"
649     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
650     attribute = de_push_sequence(service);
651     {
652         //  "UUID for Service"
653         de_add_number(attribute, DE_UUID, DE_SIZE_16, service_uuid);
654         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_GENERIC_AUDIO);
655     }
656     de_pop_sequence(service, attribute);
657 
658     // 0x0004 "Protocol Descriptor List"
659     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
660     attribute = de_push_sequence(service);
661     {
662         uint8_t* l2cpProtocol = de_push_sequence(attribute);
663         {
664             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
665         }
666         de_pop_sequence(attribute, l2cpProtocol);
667 
668         uint8_t* rfcomm = de_push_sequence(attribute);
669         {
670             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_RFCOMM);  // rfcomm_service
671             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
672         }
673         de_pop_sequence(attribute, rfcomm);
674     }
675     de_pop_sequence(service, attribute);
676 
677 
678     // 0x0005 "Public Browse Group"
679     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
680     attribute = de_push_sequence(service);
681     {
682         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
683     }
684     de_pop_sequence(service, attribute);
685 
686     // 0x0009 "Bluetooth Profile Descriptor List"
687     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
688     attribute = de_push_sequence(service);
689     {
690         uint8_t *sppProfile = de_push_sequence(attribute);
691         {
692             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_HANDSFREE);
693             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0108); // Verision 1.8
694         }
695         de_pop_sequence(attribute, sppProfile);
696     }
697     de_pop_sequence(service, attribute);
698 
699     // 0x0100 "Service Name"
700     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
701     de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
702 }
703 
704 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
705     UNUSED(packet_type);    // ok: handling own sdp events
706     UNUSED(channel);        // ok: no channel
707     UNUSED(size);           // ok: handling own sdp events
708 
709     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_bd_addr(hfp_sdp_query_context.remote_address, hfp_sdp_query_context.local_role);
710     if (hfp_connection == NULL) {
711         log_info("connection with %s and local role %d not found", hfp_sdp_query_context.remote_address, hfp_sdp_query_context.local_role);
712         return;
713     }
714 
715     switch (hci_event_packet_get_type(packet)){
716         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
717             hfp_connection->rfcomm_channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
718             break;
719         case SDP_EVENT_QUERY_COMPLETE:
720             if (hfp_connection->rfcomm_channel_nr > 0){
721                 hfp_connection->state = HFP_W4_RFCOMM_CONNECTED;
722                 btstack_packet_handler_t packet_handler;
723                 switch (hfp_connection->local_role){
724                     case HFP_ROLE_AG:
725                         packet_handler = hfp_ag_rfcomm_packet_handler;
726                         break;
727                     case HFP_ROLE_HF:
728                         packet_handler = hfp_hf_rfcomm_packet_handler;
729                         break;
730                     default:
731                         btstack_assert(false);
732                         return;
733                 }
734 
735                 rfcomm_create_channel(packet_handler, hfp_connection->remote_addr, hfp_connection->rfcomm_channel_nr, NULL);
736 
737             } else {
738                 hfp_connection->state = HFP_IDLE;
739                 uint8_t status = sdp_event_query_complete_get_status(packet);
740                 if (status == ERROR_CODE_SUCCESS){
741                     // report service not found
742                     status = SDP_SERVICE_NOT_FOUND;
743                 }
744                 hfp_emit_slc_connection_event(hfp_connection, status, HCI_CON_HANDLE_INVALID, hfp_connection->remote_addr);
745                 log_info("rfcomm service not found, status 0x%02x", status);
746             }
747 
748             // register the SDP Query request to check if there is another connection waiting for the query
749             // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
750             (void) sdp_client_register_query_callback(&hfp_sdp_query_request);
751             break;
752         default:
753             break;
754     }
755 }
756 
757 // returns 0 if unexpected error or no other link options remained, otherwise 1
758 static int hfp_handle_failed_sco_connection(uint8_t status){
759 
760     if (!hfp_sco_establishment_active){
761         log_info("(e)SCO Connection failed but not started by us");
762         return 0;
763     }
764 
765     log_info("(e)SCO Connection failed 0x%02x", status);
766     switch (status){
767         case ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE:
768         case ERROR_CODE_UNSPECIFIED_ERROR:
769         case ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES:
770             break;
771         default:
772             return 0;
773     }
774 
775     // note: eSCO_S4 supported flag not available, but it's only relevant for highest CVSD link setting (and the current failed)
776     hfp_link_settings_t next_setting = hfp_next_link_setting_for_connection(hfp_sco_establishment_active->link_setting, hfp_sco_establishment_active, false);
777 
778     // handle no valid setting found
779     if (next_setting == HFP_LINK_SETTINGS_NONE) {
780         if (hfp_sco_establishment_active->negotiated_codec == HFP_CODEC_MSBC){
781             log_info("T2/T1 failed, fallback to CVSD - D1");
782             hfp_sco_establishment_active->negotiated_codec = HFP_CODEC_CVSD;
783             hfp_sco_establishment_active->sco_for_msbc_failed = 1;
784             hfp_sco_establishment_active->command = HFP_CMD_AG_SEND_COMMON_CODEC;
785             hfp_sco_establishment_active->link_setting = HFP_LINK_SETTINGS_D1;
786         } else {
787             // no other options
788             return 0;
789         }
790     }
791 
792     log_info("e)SCO Connection: try new link_setting %d", next_setting);
793     hfp_sco_establishment_active->establish_audio_connection = 1;
794     hfp_sco_establishment_active->link_setting = next_setting;
795     hfp_sco_establishment_active = NULL;
796     return 1;
797 }
798 
799 void hfp_handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, hfp_role_t local_role){
800     UNUSED(packet_type);
801     UNUSED(channel);    // ok: no channel
802     UNUSED(size);
803 
804     bd_addr_t event_addr;
805     hci_con_handle_t handle;
806     hfp_connection_t * hfp_connection = NULL;
807     uint8_t status;
808 
809     log_debug("HFP HCI event handler type %u, event type %x, size %u", packet_type, hci_event_packet_get_type(packet), size);
810 
811     switch (hci_event_packet_get_type(packet)) {
812 
813         case HCI_EVENT_CONNECTION_REQUEST:
814             switch(hci_event_connection_request_get_link_type(packet)){
815                 case 0: //  SCO
816                 case 2: // eSCO
817                     hci_event_connection_request_get_bd_addr(packet, event_addr);
818                     hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
819                     if (!hfp_connection) break;
820                     if (hci_event_connection_request_get_link_type(packet) == 2){
821                         hfp_connection->accept_sco = 2;
822                     } else {
823                         hfp_connection->accept_sco = 1;
824                     }
825 #ifdef ENABLE_CC256X_ASSISTED_HFP
826                     hfp_cc256x_prepare_for_sco(hfp_connection);
827 #endif
828 #ifdef ENABLE_BCM_PCM_WBS
829                     hfp_bcm_prepare_for_sco(hfp_connection);
830 #endif
831                     log_info("accept sco %u\n", hfp_connection->accept_sco);
832                     hfp_sco_establishment_active = hfp_connection;
833                     break;
834                 default:
835                     break;
836             }
837             break;
838 
839         case HCI_EVENT_COMMAND_STATUS:
840             if (hci_event_command_status_get_command_opcode(packet) == hci_setup_synchronous_connection.opcode) {
841                 if (hfp_sco_establishment_active == NULL) break;
842                 status = hci_event_command_status_get_status(packet);
843                 if (status == ERROR_CODE_SUCCESS) break;
844 
845                 hfp_connection = hfp_sco_establishment_active;
846                 if (hfp_handle_failed_sco_connection(status)) break;
847                 hfp_connection->establish_audio_connection = 0;
848                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
849                 hfp_emit_sco_event(hfp_connection, status, 0, hfp_connection->remote_addr, hfp_connection->negotiated_codec);
850             }
851             break;
852 
853         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
854             if (hfp_sco_establishment_active == NULL) break;
855             hci_event_synchronous_connection_complete_get_bd_addr(packet, event_addr);
856             hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
857             if (!hfp_connection) {
858                 log_error("HFP: connection does not exist for remote with addr %s.", bd_addr_to_str(event_addr));
859                 return;
860             }
861 
862             status = hci_event_synchronous_connection_complete_get_status(packet);
863             if (status != ERROR_CODE_SUCCESS){
864                 hfp_connection->accept_sco = 0;
865                 if (hfp_handle_failed_sco_connection(status)) break;
866 
867                 hfp_connection->establish_audio_connection = 0;
868                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
869                 hfp_emit_sco_event(hfp_connection, status, 0, event_addr, hfp_connection->negotiated_codec);
870                 break;
871             }
872 
873             uint16_t sco_handle = hci_event_synchronous_connection_complete_get_handle(packet);
874             uint8_t  link_type = hci_event_synchronous_connection_complete_get_link_type(packet);
875             uint8_t  transmission_interval = hci_event_synchronous_connection_complete_get_transmission_interval(packet);  // measured in slots
876             uint8_t  retransmission_interval = hci_event_synchronous_connection_complete_get_retransmission_interval(packet);// measured in slots
877             uint16_t rx_packet_length = hci_event_synchronous_connection_complete_get_rx_packet_length(packet); // measured in bytes
878             uint16_t tx_packet_length = hci_event_synchronous_connection_complete_get_tx_packet_length(packet); // measured in bytes
879 
880             switch (link_type){
881                 case 0x00:
882                     log_info("SCO Connection established.");
883                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
884                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
885                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
886                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
887                     break;
888                 case 0x02:
889                     log_info("eSCO Connection established. \n");
890                     break;
891                 default:
892                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
893                     break;
894             }
895 
896             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
897                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)\n", sco_handle,
898                  bd_addr_to_str(event_addr), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length,
899                  hci_event_synchronous_connection_complete_get_air_mode(packet));
900 
901             if (hfp_connection->state == HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
902                 log_info("SCO about to disconnect: HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN");
903                 hfp_connection->state = HFP_W2_DISCONNECT_SCO;
904                 break;
905             }
906             hfp_connection->sco_handle = sco_handle;
907             hfp_connection->establish_audio_connection = 0;
908 
909             hfp_connection->state = HFP_AUDIO_CONNECTION_ESTABLISHED;
910 
911             switch (hfp_connection->vra_state){
912                 case HFP_VRA_VOICE_RECOGNITION_ACTIVATED:
913                     hfp_connection->ag_audio_connection_opened_before_vra = false;
914                     break;
915                 default:
916                     hfp_connection->ag_audio_connection_opened_before_vra = true;
917                     break;
918             }
919             hfp_emit_sco_event(hfp_connection, status, sco_handle, event_addr, hfp_connection->negotiated_codec);
920             break;
921         }
922 
923         case HCI_EVENT_DISCONNECTION_COMPLETE:
924             handle = little_endian_read_16(packet,3);
925             hfp_connection = get_hfp_connection_context_for_sco_handle(handle, local_role);
926 
927             if (!hfp_connection) break;
928 
929 #ifdef ENABLE_CC256X_ASSISTED_HFP
930             hfp_connection->cc256x_send_wbs_disassociate = true;
931 #endif
932 #ifdef ENABLE_BCM_PCM_WBS
933             hfp_connection->bcm_send_disable_wbs = true;
934 #endif
935             if (hfp_connection->sco_handle == handle){
936                 hfp_connection->sco_handle = HCI_CON_HANDLE_INVALID;
937                 hfp_connection->release_audio_connection = 0;
938                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
939                 hfp_emit_audio_connection_released(hfp_connection, handle);
940 
941                 hfp_connection->ag_audio_connection_opened_before_vra = false;
942 
943                 if (hfp_connection->acl_handle == HCI_CON_HANDLE_INVALID){
944                     hfp_reset_voice_recognition(hfp_connection);
945                     hfp_emit_event(hfp_connection, HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_RELEASED, 0);
946                     hfp_finalize_connection_context(hfp_connection);
947                 } else if (hfp_connection->release_slc_connection == 1){
948                     hfp_connection->release_slc_connection = 0;
949                     hfp_connection->state = HFP_W2_DISCONNECT_RFCOMM;
950                     rfcomm_disconnect(hfp_connection->acl_handle);
951                 }
952             }
953 
954             if (hfp_connection->state == HFP_W4_SCO_DISCONNECTED_TO_SHUTDOWN){
955                 // RFCOMM already closed -> remote power off
956 #if defined(ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
957                 hfp_connection->state = HFP_W4_WBS_SHUTDOWN;
958 #else
959                 hfp_finalize_connection_context(hfp_connection);
960 #endif
961                 break;
962             }
963             break;
964 
965         default:
966             break;
967     }
968 }
969 
970 
971 void hfp_handle_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, hfp_role_t local_role){
972     UNUSED(packet_type);
973     UNUSED(channel);    // ok: no channel
974     UNUSED(size);
975 
976     bd_addr_t event_addr;
977     uint16_t rfcomm_cid;
978     hfp_connection_t * hfp_connection = NULL;
979     uint8_t status;
980 
981     log_debug("HFP packet_handler type %u, event type %x, size %u", packet_type, hci_event_packet_get_type(packet), size);
982 
983     switch (hci_event_packet_get_type(packet)) {
984 
985         case RFCOMM_EVENT_INCOMING_CONNECTION:
986             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
987             rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr);
988             hfp_connection = hfp_create_connection(event_addr, local_role);
989             if (!hfp_connection){
990                 log_info("hfp: no memory to accept incoming connection - decline");
991                 rfcomm_decline_connection(rfcomm_event_incoming_connection_get_rfcomm_cid(packet));
992                 return;
993             }
994             if (hfp_connection->state != HFP_IDLE) {
995                 log_error("hfp: incoming connection but not idle, reject");
996                 rfcomm_decline_connection(rfcomm_event_incoming_connection_get_rfcomm_cid(packet));
997                 return;
998             }
999 
1000             hfp_connection->rfcomm_cid = rfcomm_event_incoming_connection_get_rfcomm_cid(packet);
1001             hfp_connection->state = HFP_W4_RFCOMM_CONNECTED;
1002             rfcomm_accept_connection(hfp_connection->rfcomm_cid);
1003             break;
1004 
1005         case RFCOMM_EVENT_CHANNEL_OPENED:
1006             rfcomm_event_channel_opened_get_bd_addr(packet, event_addr);
1007 
1008             hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
1009             btstack_assert(hfp_connection != NULL);
1010 
1011             if (hfp_connection->state != HFP_W4_RFCOMM_CONNECTED){
1012                 break;
1013             }
1014 
1015             status = rfcomm_event_channel_opened_get_status(packet);
1016             if (status != ERROR_CODE_SUCCESS) {
1017                 hfp_emit_slc_connection_event(hfp_connection, status, rfcomm_event_channel_opened_get_con_handle(packet), event_addr);
1018                 hfp_finalize_connection_context(hfp_connection);
1019                 break;
1020             }
1021 
1022             hfp_connection->acl_handle = rfcomm_event_channel_opened_get_con_handle(packet);
1023             hfp_connection->rfcomm_cid = rfcomm_event_channel_opened_get_rfcomm_cid(packet);
1024             hfp_connection->rfcomm_mtu = rfcomm_event_channel_opened_get_max_frame_size(packet);
1025             bd_addr_copy(hfp_connection->remote_addr, event_addr);
1026             hfp_connection->state = HFP_EXCHANGE_SUPPORTED_FEATURES;
1027 
1028             rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1029             break;
1030 
1031         case RFCOMM_EVENT_CHANNEL_CLOSED:
1032             rfcomm_cid = little_endian_read_16(packet,2);
1033             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
1034             if (!hfp_connection) break;
1035             switch (hfp_connection->state){
1036                 case HFP_W4_RFCOMM_DISCONNECTED_AND_RESTART:
1037                     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
1038                     hfp_connection->state = HFP_IDLE;
1039                     hfp_establish_service_level_connection(hfp_connection->remote_addr, hfp_connection->service_uuid, local_role);
1040                     break;
1041 
1042                 case HFP_AUDIO_CONNECTION_ESTABLISHED:
1043                     // service connection was released, this implicitly releases audio connection as well
1044                     hfp_connection->release_audio_connection = 0;
1045                     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
1046                     hfp_connection->state = HFP_W4_SCO_DISCONNECTED_TO_SHUTDOWN;
1047                     gap_disconnect(hfp_connection->sco_handle);
1048                     break;
1049 
1050                 default:
1051                     // regular case
1052                     hfp_reset_voice_recognition(hfp_connection);
1053                     hfp_emit_event(hfp_connection, HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_RELEASED, 0);
1054                     hfp_finalize_connection_context(hfp_connection);
1055                     break;
1056             }
1057             break;
1058 
1059         default:
1060             break;
1061     }
1062 }
1063 // translates command string into hfp_command_t CMD
1064 
1065 typedef struct {
1066     const char * command;
1067     hfp_command_t command_id;
1068 } hfp_command_entry_t;
1069 
1070 static hfp_command_entry_t hfp_ag_commmand_table[] = {
1071     { "AT+BAC=",   HFP_CMD_AVAILABLE_CODECS },
1072     { "AT+BCC",    HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP },
1073     { "AT+BCS=",   HFP_CMD_HF_CONFIRMED_CODEC },
1074     { "AT+BIA=",   HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE, }, // +BIA:<enabled>,,<enabled>,,,<enabled>
1075     { "AT+BIEV=",  HFP_CMD_HF_INDICATOR_STATUS },
1076     { "AT+BIND=",  HFP_CMD_LIST_GENERIC_STATUS_INDICATORS },
1077     { "AT+BIND=?", HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS },
1078     { "AT+BIND?",  HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE },
1079     { "AT+BINP=",  HFP_CMD_HF_REQUEST_PHONE_NUMBER },
1080     { "AT+BLDN",   HFP_CMD_REDIAL_LAST_NUMBER },
1081     { "AT+BRSF=",  HFP_CMD_SUPPORTED_FEATURES },
1082     { "AT+BTRH=",  HFP_CMD_RESPONSE_AND_HOLD_COMMAND },
1083     { "AT+BTRH?",  HFP_CMD_RESPONSE_AND_HOLD_QUERY },
1084     { "AT+BVRA=",  HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION },
1085     { "AT+CCWA=",  HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION},
1086     { "AT+CHLD=",  HFP_CMD_CALL_HOLD },
1087     { "AT+CHLD=?", HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES },
1088     { "AT+CHUP",   HFP_CMD_HANG_UP_CALL },
1089     { "AT+CIND=?", HFP_CMD_RETRIEVE_AG_INDICATORS },
1090     { "AT+CIND?",  HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS },
1091     { "AT+CLCC",   HFP_CMD_LIST_CURRENT_CALLS },
1092     { "AT+CLIP=",  HFP_CMD_ENABLE_CLIP},
1093     { "AT+CMEE=",  HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR},
1094     { "AT+CMER=",  HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE },
1095     { "AT+CNUM",   HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION },
1096     { "AT+COPS=",  HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT },
1097     { "AT+COPS?",  HFP_CMD_QUERY_OPERATOR_SELECTION_NAME },
1098     { "AT+NREC=",  HFP_CMD_TURN_OFF_EC_AND_NR, },
1099     { "AT+VGM=",   HFP_CMD_SET_MICROPHONE_GAIN },
1100     { "AT+VGS=",   HFP_CMD_SET_SPEAKER_GAIN },
1101     { "AT+VTS=",   HFP_CMD_TRANSMIT_DTMF_CODES },
1102     { "ATA",       HFP_CMD_CALL_ANSWERED },
1103 };
1104 
1105 static hfp_command_entry_t hfp_hf_commmand_table[] = {
1106     { "+BCS:",  HFP_CMD_AG_SUGGESTED_CODEC },
1107     { "+BIND:", HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS },
1108     { "+BINP",  HFP_CMD_AG_SENT_PHONE_NUMBER },
1109     { "+BRSF:", HFP_CMD_SUPPORTED_FEATURES },
1110     { "+BSIR:", HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING },
1111     { "+BTRH:", HFP_CMD_RESPONSE_AND_HOLD_STATUS },
1112     { "+BVRA:", HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION },
1113     { "+CCWA:", HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE, },
1114     { "+CHLD:", HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES },
1115     { "+CIEV:", HFP_CMD_TRANSFER_AG_INDICATOR_STATUS},
1116     { "+CIND:", HFP_CMD_RETRIEVE_AG_INDICATORS_GENERIC },
1117     { "+CLCC:", HFP_CMD_LIST_CURRENT_CALLS },
1118     { "+CLIP:", HFP_CMD_AG_SENT_CLIP_INFORMATION },
1119     { "+CME ERROR:", HFP_CMD_EXTENDED_AUDIO_GATEWAY_ERROR },
1120     { "+CNUM:", HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION},
1121     { "+COPS:", HFP_CMD_QUERY_OPERATOR_SELECTION_NAME },
1122     { "+VGM:",  HFP_CMD_SET_MICROPHONE_GAIN },
1123     { "+VGS:",  HFP_CMD_SET_SPEAKER_GAIN},
1124     { "ERROR",  HFP_CMD_ERROR},
1125     { "NOP",    HFP_CMD_NONE}, // dummy command used by unit tests
1126     { "OK",     HFP_CMD_OK },
1127     { "RING",   HFP_CMD_RING },
1128 };
1129 
1130 static hfp_command_t parse_command(const char * line_buffer, int isHandsFree){
1131 
1132     // table lookup based on role
1133     uint16_t num_entries;
1134     hfp_command_entry_t * table;
1135     if (isHandsFree == 0){
1136         table = hfp_ag_commmand_table;
1137         num_entries = sizeof(hfp_ag_commmand_table) / sizeof(hfp_command_entry_t);
1138     } else {
1139         table = hfp_hf_commmand_table;
1140         num_entries = sizeof(hfp_hf_commmand_table) / sizeof(hfp_command_entry_t);
1141     }
1142     // binary search
1143     uint16_t left = 0;
1144     uint16_t right = num_entries - 1;
1145     while (left <= right){
1146         uint16_t middle = left + (right - left) / 2;
1147         hfp_command_entry_t *entry = &table[middle];
1148         int match = strcmp(line_buffer, entry->command);
1149         if (match < 0){
1150             // search term is lower than middle element
1151             if (right == 0) break;
1152             right = middle - 1;
1153         } else if (match == 0){
1154             return entry->command_id;
1155         } else {
1156             // search term is higher than middle element
1157             left = middle + 1;
1158         }
1159     }
1160 
1161     // note: if parser in CMD_HEADER state would treats digits and maybe '+' as separator, match on "ATD" would work.
1162     // note: phone number is currently expected in line_buffer[3..]
1163     // prefix match on 'ATD', AG only
1164     if ((isHandsFree == 0) && (strncmp(line_buffer, HFP_CALL_PHONE_NUMBER, strlen(HFP_CALL_PHONE_NUMBER)) == 0)){
1165         return HFP_CMD_CALL_PHONE_NUMBER;
1166     }
1167 
1168     // Valid looking, but unknown commands/responses
1169     if ((isHandsFree == 0) && (strncmp(line_buffer, "AT+", 3) == 0)){
1170         return HFP_CMD_UNKNOWN;
1171     }
1172 
1173     if ((isHandsFree != 0) && (strncmp(line_buffer, "+", 1) == 0)){
1174         return HFP_CMD_UNKNOWN;
1175     }
1176 
1177     return HFP_CMD_NONE;
1178 }
1179 
1180 static void hfp_parser_store_byte(hfp_connection_t * hfp_connection, uint8_t byte){
1181     if ((hfp_connection->line_size + 1) >= HFP_MAX_VR_TEXT_SIZE) return;
1182     hfp_connection->line_buffer[hfp_connection->line_size++] = byte;
1183     hfp_connection->line_buffer[hfp_connection->line_size] = 0;
1184 }
1185 static int hfp_parser_is_buffer_empty(hfp_connection_t * hfp_connection){
1186     return hfp_connection->line_size == 0;
1187 }
1188 
1189 static int hfp_parser_is_end_of_line(uint8_t byte){
1190     return (byte == '\n') || (byte == '\r');
1191 }
1192 
1193 static void hfp_parser_reset_line_buffer(hfp_connection_t *hfp_connection) {
1194     hfp_connection->line_size = 0;
1195     // hfp_connection->line_buffer[0] = 0;
1196 }
1197 
1198 static void hfp_parser_store_if_token(hfp_connection_t * hfp_connection, uint8_t byte){
1199     switch (byte){
1200         case ',':
1201 		case '-':
1202         case ';':
1203         case '(':
1204         case ')':
1205         case '\n':
1206         case '\r':
1207             break;
1208         default:
1209             hfp_parser_store_byte(hfp_connection, byte);
1210             break;
1211     }
1212 }
1213 
1214 static bool hfp_parser_is_separator( uint8_t byte){
1215     switch (byte){
1216         case ',':
1217 		case '-':
1218         case ';':
1219         case '\n':
1220         case '\r':
1221             return true;
1222         default:
1223             return false;
1224     }
1225 }
1226 
1227 static bool hfp_parse_byte(hfp_connection_t * hfp_connection, uint8_t byte, int isHandsFree){
1228 
1229     // handle doubles quotes
1230     if (byte == '"'){
1231         hfp_connection->parser_quoted = !hfp_connection->parser_quoted;
1232         return true;
1233     }
1234     if (hfp_connection->parser_quoted) {
1235         hfp_parser_store_byte(hfp_connection, byte);
1236         return true;
1237     }
1238 
1239     // ignore spaces outside command or double quotes (required e.g. for '+CME ERROR:..") command
1240     if ((byte == ' ') && (hfp_connection->parser_state != HFP_PARSER_CMD_HEADER)) return true;
1241 
1242     bool processed = true;
1243 
1244     switch (hfp_connection->parser_state) {
1245         case HFP_PARSER_CMD_HEADER:
1246             switch (byte) {
1247                 case '\n':
1248                 case '\r':
1249                 case ';':
1250                     // ignore separator
1251                     break;
1252                 case ':':
1253                 case '?':
1254                     // store separator
1255                     hfp_parser_store_byte(hfp_connection, byte);
1256                     break;
1257                 case '=':
1258                     // equal sign: remember and wait for next char to decided between '=?' and '=\?'
1259                     hfp_connection->found_equal_sign = true;
1260                     hfp_parser_store_byte(hfp_connection, byte);
1261                     return true;
1262                 default:
1263                     // store if not lookahead
1264                     if (!hfp_connection->found_equal_sign) {
1265                         hfp_parser_store_byte(hfp_connection, byte);
1266                         return true;
1267                     }
1268                     // mark as lookahead
1269                     processed = false;
1270                     break;
1271             }
1272 
1273             // ignore empty tokens
1274             if (hfp_parser_is_buffer_empty(hfp_connection)) return true;
1275 
1276             // parse
1277             hfp_connection->command = parse_command((char *)hfp_connection->line_buffer, isHandsFree);
1278 
1279             // pick +CIND version based on connection state: descriptions during SLC vs. states later
1280             if (hfp_connection->command == HFP_CMD_RETRIEVE_AG_INDICATORS_GENERIC){
1281                 switch(hfp_connection->state){
1282                     case HFP_W4_RETRIEVE_INDICATORS_STATUS:
1283                         hfp_connection->command = HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS;
1284                         break;
1285                     case HFP_W4_RETRIEVE_INDICATORS:
1286                         hfp_connection->command = HFP_CMD_RETRIEVE_AG_INDICATORS;
1287                         break;
1288                     default:
1289                         hfp_connection->command = HFP_CMD_UNKNOWN;
1290                         break;
1291                 }
1292             }
1293 
1294             log_info("command string '%s', handsfree %u -> cmd id %u", (char *)hfp_connection->line_buffer, isHandsFree, hfp_connection->command);
1295 
1296             // next state
1297             hfp_connection->found_equal_sign = false;
1298             hfp_parser_reset_line_buffer(hfp_connection);
1299             hfp_connection->parser_state = HFP_PARSER_CMD_SEQUENCE;
1300 
1301             return processed;
1302 
1303         case HFP_PARSER_CMD_SEQUENCE:
1304             // handle empty fields
1305             if ((byte == ',' ) && (hfp_connection->line_size == 0)){
1306                 hfp_connection->line_buffer[0] = 0;
1307                 hfp_connection->ignore_value = 1;
1308                 parse_sequence(hfp_connection);
1309                 return true;
1310             }
1311 
1312             hfp_parser_store_if_token(hfp_connection, byte);
1313             if (!hfp_parser_is_separator(byte)) return true;
1314 
1315             // ignore empty tokens
1316             switch (hfp_connection->command){
1317                 case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
1318                     // don't ignore empty string
1319                     break;
1320                 default:
1321                     if (hfp_parser_is_buffer_empty(hfp_connection) && (hfp_connection->ignore_value == 0)) {
1322                         return true;
1323                     }
1324                     break;
1325             }
1326 
1327             parse_sequence(hfp_connection);
1328 
1329             hfp_parser_reset_line_buffer(hfp_connection);
1330 
1331             switch (hfp_connection->command){
1332                 case HFP_CMD_AG_SENT_PHONE_NUMBER:
1333                 case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1334                 case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1335                 case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1336                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1337                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1338                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1339                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1340                 case HFP_CMD_HF_INDICATOR_STATUS:
1341                     hfp_connection->parser_state = HFP_PARSER_SECOND_ITEM;
1342                     break;
1343                 default:
1344                     break;
1345             }
1346             return true;
1347 
1348         case HFP_PARSER_SECOND_ITEM:
1349 
1350             hfp_parser_store_if_token(hfp_connection, byte);
1351             if (!hfp_parser_is_separator(byte)) return true;
1352 
1353             switch (hfp_connection->command){
1354                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1355                     log_info("format %s, ", hfp_connection->line_buffer);
1356                     hfp_connection->network_operator.format =  btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1357                     break;
1358                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1359                     log_info("format %s \n", hfp_connection->line_buffer);
1360                     hfp_connection->network_operator.format =  btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1361                     break;
1362                 case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
1363                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
1364                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1365                     hfp_connection->generic_status_indicators[hfp_connection->parser_item_index].state = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1366                     break;
1367                 case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1368                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].status = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1369                     log_info("%d \n", hfp_connection->ag_indicators[hfp_connection->parser_item_index].status);
1370                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].status_changed = 1;
1371                     break;
1372                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1373                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].min_range = btstack_atoi((char *)hfp_connection->line_buffer);
1374                     log_info("%s, ", hfp_connection->line_buffer);
1375                     break;
1376                 case HFP_CMD_AG_SENT_PHONE_NUMBER:
1377                 case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1378                 case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1379                     hfp_connection->bnip_type = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1380                     break;
1381                 case HFP_CMD_HF_INDICATOR_STATUS:
1382                     hfp_connection->parser_indicator_value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1383                     break;
1384                 default:
1385                     break;
1386             }
1387 
1388             hfp_parser_reset_line_buffer(hfp_connection);
1389 
1390             hfp_connection->parser_state = HFP_PARSER_THIRD_ITEM;
1391 
1392             return true;
1393 
1394         case HFP_PARSER_THIRD_ITEM:
1395 
1396             hfp_parser_store_if_token(hfp_connection, byte);
1397             if (!hfp_parser_is_separator(byte)) return true;
1398 
1399             switch (hfp_connection->command){
1400                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1401                     strncpy(hfp_connection->network_operator.name, (char *)hfp_connection->line_buffer, HFP_MAX_NETWORK_OPERATOR_NAME_SIZE);
1402                     hfp_connection->network_operator.name[HFP_MAX_NETWORK_OPERATOR_NAME_SIZE - 1] = 0;
1403                     log_info("name %s\n", hfp_connection->line_buffer);
1404                     break;
1405                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1406                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].max_range = btstack_atoi((char *)hfp_connection->line_buffer);
1407                     hfp_next_indicators_index(hfp_connection);
1408                     hfp_connection->ag_indicators_nr = hfp_connection->parser_item_index;
1409                     log_info("%s)\n", hfp_connection->line_buffer);
1410                     break;
1411                 default:
1412                     break;
1413             }
1414 
1415             hfp_parser_reset_line_buffer(hfp_connection);
1416 
1417             if (hfp_connection->command == HFP_CMD_RETRIEVE_AG_INDICATORS){
1418                 hfp_connection->parser_state = HFP_PARSER_CMD_SEQUENCE;
1419             } else {
1420                 hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
1421             }
1422             return true;
1423 
1424         default:
1425             btstack_assert(false);
1426             return true;
1427     }
1428 }
1429 
1430 void hfp_parse(hfp_connection_t * hfp_connection, uint8_t byte, int isHandsFree){
1431     bool processed = false;
1432     while (!processed){
1433         processed = hfp_parse_byte(hfp_connection, byte, isHandsFree);
1434     }
1435     // reset parser state on end-of-line
1436     if (hfp_parser_is_end_of_line(byte)){
1437         hfp_connection->parser_item_index = 0;
1438         hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
1439     }
1440 }
1441 
1442 static void parse_sequence(hfp_connection_t * hfp_connection){
1443     int value;
1444     switch (hfp_connection->command){
1445         case HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS:
1446             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1447             int i;
1448             switch (hfp_connection->parser_item_index){
1449                 case 0:
1450                     for (i=0;i<hfp_connection->generic_status_indicators_nr;i++){
1451                         if (hfp_connection->generic_status_indicators[i].uuid == value){
1452                             hfp_connection->parser_indicator_index = i;
1453                             break;
1454                         }
1455                     }
1456                     break;
1457                 case 1:
1458                     if (hfp_connection->parser_indicator_index <0) break;
1459                     hfp_connection->generic_status_indicators[hfp_connection->parser_indicator_index].state = value;
1460                     log_info("HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS set indicator at index %u, to %u\n",
1461                      hfp_connection->parser_item_index, value);
1462                     break;
1463                 default:
1464                     break;
1465             }
1466             hfp_next_indicators_index(hfp_connection);
1467             break;
1468 
1469         case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
1470             switch(hfp_connection->parser_item_index){
1471                 case 0:
1472                     // <alpha>: This optional field is not supported, and shall be left blank.
1473                     break;
1474                 case 1:
1475                     // <number>: Quoted string containing the phone number in the format specified by <type>.
1476                     strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1477                     hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1478                     break;
1479                 case 2:
1480                     /*
1481                       <type> field specifies the format of the phone number provided, and can be one of the following values:
1482                       - values 128-143: The phone number format may be a national or international format, and may contain prefix and/or escape digits. No changes on the number presentation are required.
1483                      - values 144-159: The phone number format is an international number, including the country code prefix. If the plus sign ("+") is not included as part of the number and shall be added by the AG as needed.
1484                      - values 160-175: National number. No prefix nor escape digits included.
1485                      */
1486                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1487                     hfp_connection->bnip_type = value;
1488                     break;
1489                 case 3:
1490                     // <speed>: This optional field is not supported, and shall be left blank.
1491                     break;
1492                 case 4:
1493                     // <service>: Indicates which service this phone number relates to. Shall be either 4 (voice) or 5 (fax).
1494                 default:
1495                     break;
1496             }
1497             // index > 2 are ignored in switch above
1498             hfp_connection->parser_item_index++;
1499             break;
1500         case HFP_CMD_LIST_CURRENT_CALLS:
1501             switch(hfp_connection->parser_item_index){
1502                 case 0:
1503                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1504                     hfp_connection->clcc_idx = value;
1505                     break;
1506                 case 1:
1507                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1508                     hfp_connection->clcc_dir = value;
1509                     break;
1510                 case 2:
1511                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1512                     hfp_connection->clcc_status = value;
1513                     break;
1514                 case 3:
1515                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1516                     hfp_connection->clcc_mode = value;
1517                     break;
1518                 case 4:
1519                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1520                     hfp_connection->clcc_mpty = value;
1521                     break;
1522                 case 5:
1523                     strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1524                     hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1525                     break;
1526                 case 6:
1527                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1528                     hfp_connection->bnip_type = value;
1529                     break;
1530                 default:
1531                     break;
1532             }
1533             // index > 6 are ignored in switch above
1534             hfp_connection->parser_item_index++;
1535             break;
1536         case HFP_CMD_SET_MICROPHONE_GAIN:
1537             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1538             hfp_connection->microphone_gain = value;
1539             log_info("hfp parse HFP_CMD_SET_MICROPHONE_GAIN %d\n", value);
1540             break;
1541         case HFP_CMD_SET_SPEAKER_GAIN:
1542             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1543             hfp_connection->speaker_gain = value;
1544             log_info("hfp parse HFP_CMD_SET_SPEAKER_GAIN %d\n", value);
1545             break;
1546         case HFP_CMD_TURN_OFF_EC_AND_NR:
1547             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1548             hfp_connection->ag_echo_and_noise_reduction = value;
1549             log_info("hfp parse HFP_CMD_TURN_OFF_EC_AND_NR %d\n", value);
1550             break;
1551         case HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING:
1552             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1553             hfp_connection->remote_supported_features = store_bit(hfp_connection->remote_supported_features, HFP_AGSF_IN_BAND_RING_TONE, value);
1554             log_info("hfp parse HFP_CHANGE_IN_BAND_RING_TONE_SETTING %d\n", value);
1555             break;
1556         case HFP_CMD_HF_CONFIRMED_CODEC:
1557             hfp_connection->codec_confirmed = btstack_atoi((char*)hfp_connection->line_buffer);
1558             log_info("hfp parse HFP_CMD_HF_CONFIRMED_CODEC %d\n", hfp_connection->codec_confirmed);
1559             break;
1560         case HFP_CMD_AG_SUGGESTED_CODEC:
1561             hfp_connection->suggested_codec = btstack_atoi((char*)hfp_connection->line_buffer);
1562             log_info("hfp parse HFP_CMD_AG_SUGGESTED_CODEC %d\n", hfp_connection->suggested_codec);
1563             break;
1564         case HFP_CMD_SUPPORTED_FEATURES:
1565             hfp_connection->remote_supported_features = btstack_atoi((char*)hfp_connection->line_buffer);
1566             log_info("Parsed supported feature %d\n", (int) hfp_connection->remote_supported_features);
1567             break;
1568         case HFP_CMD_AVAILABLE_CODECS:
1569             log_info("Parsed codec %s\n", hfp_connection->line_buffer);
1570             hfp_connection->remote_codecs[hfp_connection->parser_item_index] = (uint16_t)btstack_atoi((char*)hfp_connection->line_buffer);
1571             hfp_next_codec_index(hfp_connection);
1572             hfp_connection->remote_codecs_nr = hfp_connection->parser_item_index;
1573             break;
1574         case HFP_CMD_RETRIEVE_AG_INDICATORS:
1575             strncpy((char *)hfp_connection->ag_indicators[hfp_connection->parser_item_index].name,  (char *)hfp_connection->line_buffer, HFP_MAX_INDICATOR_DESC_SIZE);
1576             hfp_connection->ag_indicators[hfp_connection->parser_item_index].name[HFP_MAX_INDICATOR_DESC_SIZE-1] = 0;
1577             hfp_connection->ag_indicators[hfp_connection->parser_item_index].index = hfp_connection->parser_item_index+1;
1578             log_info("Indicator %d: %s (", hfp_connection->ag_indicators_nr+1, hfp_connection->line_buffer);
1579             break;
1580         case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
1581             log_info("Parsed Indicator %d with status: %s\n", hfp_connection->parser_item_index+1, hfp_connection->line_buffer);
1582             hfp_connection->ag_indicators[hfp_connection->parser_item_index].status = btstack_atoi((char *) hfp_connection->line_buffer);
1583             hfp_next_indicators_index(hfp_connection);
1584             break;
1585         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
1586             hfp_next_indicators_index(hfp_connection);
1587             if (hfp_connection->parser_item_index != 4) break;
1588             log_info("Parsed Enable indicators: %s\n", hfp_connection->line_buffer);
1589             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1590             hfp_connection->enable_status_update_for_ag_indicators = (uint8_t) value;
1591             break;
1592         case HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES:
1593             log_info("Parsed Support call hold: %s\n", hfp_connection->line_buffer);
1594             if (hfp_connection->line_size > 2 ) break;
1595             memcpy((char *)hfp_connection->remote_call_services[hfp_connection->remote_call_services_index].name, (char *)hfp_connection->line_buffer, HFP_CALL_SERVICE_SIZE-1);
1596             hfp_connection->remote_call_services[hfp_connection->remote_call_services_index].name[HFP_CALL_SERVICE_SIZE - 1] = 0;
1597             hfp_next_remote_call_services_index(hfp_connection);
1598             break;
1599         case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
1600         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
1601             log_info("Parsed Generic status indicator: %s\n", hfp_connection->line_buffer);
1602             hfp_connection->generic_status_indicators[hfp_connection->parser_item_index].uuid = (uint16_t)btstack_atoi((char*)hfp_connection->line_buffer);
1603             hfp_next_indicators_index(hfp_connection);
1604             hfp_connection->generic_status_indicators_nr = hfp_connection->parser_item_index;
1605             break;
1606         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1607             // HF parses inital AG gen. ind. state
1608             log_info("Parsed List generic status indicator %s state: ", hfp_connection->line_buffer);
1609             hfp_connection->parser_item_index = hfp_parse_indicator_index(hfp_connection);
1610             break;
1611         case HFP_CMD_HF_INDICATOR_STATUS:
1612             hfp_connection->parser_indicator_index = hfp_parse_indicator_index(hfp_connection);
1613             log_info("Parsed HF indicator index %u", hfp_connection->parser_indicator_index);
1614             break;
1615         case HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE:
1616             // AG parses new gen. ind. state
1617             if (hfp_connection->ignore_value){
1618                 hfp_connection->ignore_value = 0;
1619                 log_info("Parsed Enable AG indicator pos %u('%s') - unchanged (stays %u)\n", hfp_connection->parser_item_index,
1620                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].name, hfp_connection->ag_indicators[hfp_connection->parser_item_index].enabled);
1621             }
1622             else if (hfp_connection->ag_indicators[hfp_connection->parser_item_index].mandatory){
1623                 log_info("Parsed Enable AG indicator pos %u('%s') - ignore (mandatory)\n",
1624                     hfp_connection->parser_item_index, hfp_connection->ag_indicators[hfp_connection->parser_item_index].name);
1625             } else {
1626                 value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1627                 hfp_connection->ag_indicators[hfp_connection->parser_item_index].enabled = value;
1628                 log_info("Parsed Enable AG indicator pos %u('%s'): %u\n", hfp_connection->parser_item_index,
1629                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].name, value);
1630             }
1631             hfp_next_indicators_index(hfp_connection);
1632             break;
1633         case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1634             // indicators are indexed starting with 1
1635             hfp_connection->parser_item_index = hfp_parse_indicator_index(hfp_connection);
1636             log_info("Parsed status of the AG indicator %d, status ", hfp_connection->parser_item_index);
1637             break;
1638         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1639             hfp_connection->network_operator.mode = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1640             log_info("Parsed network operator mode: %d, ", hfp_connection->network_operator.mode);
1641             break;
1642         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1643             if (hfp_connection->line_buffer[0] == '3'){
1644                 log_info("Parsed Set network operator format : %s, ", hfp_connection->line_buffer);
1645                 break;
1646             }
1647             // TODO emit ERROR, wrong format
1648             log_info("ERROR Set network operator format: index %s not supported\n", hfp_connection->line_buffer);
1649             break;
1650         case HFP_CMD_ERROR:
1651             break;
1652         case HFP_CMD_EXTENDED_AUDIO_GATEWAY_ERROR:
1653             hfp_connection->extended_audio_gateway_error = 1;
1654             hfp_connection->extended_audio_gateway_error_value = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1655             break;
1656         case HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR:
1657             hfp_connection->enable_extended_audio_gateway_error_report = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1658             hfp_connection->ok_pending = 1;
1659             hfp_connection->extended_audio_gateway_error = 0;
1660             break;
1661         case HFP_CMD_AG_SENT_PHONE_NUMBER:
1662         case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1663         case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1664             strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1665             hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1666             break;
1667         case HFP_CMD_CALL_HOLD:
1668             hfp_connection->ag_call_hold_action = hfp_connection->line_buffer[0] - '0';
1669             if (hfp_connection->line_buffer[1] != '\0'){
1670                 hfp_connection->call_index = btstack_atoi((char *)&hfp_connection->line_buffer[1]);
1671             }
1672             break;
1673         case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
1674             hfp_connection->ag_response_and_hold_action = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1675             break;
1676         case HFP_CMD_TRANSMIT_DTMF_CODES:
1677             hfp_connection->ag_dtmf_code = hfp_connection->line_buffer[0];
1678             break;
1679         case HFP_CMD_ENABLE_CLIP:
1680             hfp_connection->clip_enabled = hfp_connection->line_buffer[0] != '0';
1681             break;
1682         case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
1683             hfp_connection->call_waiting_notification_enabled = hfp_connection->line_buffer[0] != '0';
1684             break;
1685         case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
1686             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1687             hfp_connection->ag_activate_voice_recognition_value = value;
1688             break;
1689         case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
1690             switch(hfp_connection->parser_item_index){
1691                 case 0:
1692                     hfp_connection->ag_vra_status = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1693                     break;
1694                 case 1:
1695                     hfp_connection->ag_vra_state = (hfp_voice_recognition_state_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1696                     break;
1697                 case 2:
1698                     hfp_connection->ag_msg.text_id = 0;
1699                     for (i = 0 ; i < 4; i++){
1700                         hfp_connection->ag_msg.text_id = (hfp_connection->ag_msg.text_id << 4) | nibble_for_char(hfp_connection->line_buffer[i]);
1701                     }
1702                     break;
1703                 case 3:
1704                     hfp_connection->ag_msg.text_operation = (hfp_text_operation_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1705                     break;
1706                 case 4:
1707                     hfp_connection->ag_msg.text_type = (hfp_text_type_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1708                     break;
1709                 case 5:
1710                     hfp_connection->line_buffer[hfp_connection->line_size] = 0;
1711                     hfp_connection->ag_vra_msg_length = hfp_connection->line_size + 1;
1712                     break;
1713                 default:
1714                     break;
1715             }
1716             hfp_connection->parser_item_index++;
1717             break;
1718         default:
1719             break;
1720     }
1721 }
1722 
1723 static void hfp_handle_start_sdp_client_query(void * context){
1724     UNUSED(context);
1725 
1726     btstack_linked_list_iterator_t it;
1727     btstack_linked_list_iterator_init(&it, &hfp_connections);
1728     while (btstack_linked_list_iterator_has_next(&it)){
1729         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1730 
1731         if (connection->state != HFP_W2_SEND_SDP_QUERY) continue;
1732 
1733         connection->state = HFP_W4_SDP_QUERY_COMPLETE;
1734         hfp_sdp_query_context.local_role = connection->local_role;
1735         (void)memcpy(hfp_sdp_query_context.remote_address, connection->remote_addr, 6);
1736         sdp_client_query_rfcomm_channel_and_name_for_service_class_uuid(&handle_query_rfcomm_event, connection->remote_addr, connection->service_uuid);
1737         return;
1738     }
1739 }
1740 
1741 uint8_t hfp_establish_service_level_connection(bd_addr_t bd_addr, uint16_t service_uuid, hfp_role_t local_role){
1742     hfp_connection_t * connection = get_hfp_connection_context_for_bd_addr(bd_addr, local_role);
1743     if (connection){
1744         return ERROR_CODE_COMMAND_DISALLOWED;
1745     }
1746 
1747     connection = hfp_create_connection(bd_addr, local_role);
1748     if (!connection){
1749         return BTSTACK_MEMORY_ALLOC_FAILED;
1750     }
1751 
1752     connection->state = HFP_W2_SEND_SDP_QUERY;
1753 
1754     bd_addr_copy(connection->remote_addr, bd_addr);
1755     connection->service_uuid = service_uuid;
1756 
1757     hfp_sdp_query_request.callback = &hfp_handle_start_sdp_client_query;
1758     // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
1759     (void) sdp_client_register_query_callback(&hfp_sdp_query_request);
1760     return ERROR_CODE_SUCCESS;
1761 }
1762 
1763 void hfp_trigger_release_service_level_connection(hfp_connection_t * hfp_connection){
1764     // called internally, NULL check already performed
1765     btstack_assert(hfp_connection != NULL);
1766 
1767     hfp_trigger_release_audio_connection(hfp_connection);
1768     if (hfp_connection->state < HFP_W4_RFCOMM_CONNECTED){
1769         hfp_connection->state = HFP_IDLE;
1770         return;
1771     }
1772 
1773     if (hfp_connection->state == HFP_W4_RFCOMM_CONNECTED){
1774         hfp_connection->state = HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
1775         return;
1776     }
1777     hfp_connection->release_slc_connection = 1;
1778     if (hfp_connection->state < HFP_W4_SCO_CONNECTED){
1779         hfp_connection->state = HFP_W2_DISCONNECT_RFCOMM;
1780         return;
1781     }
1782 
1783     if (hfp_connection->state < HFP_W4_SCO_DISCONNECTED){
1784         hfp_connection->state = HFP_W2_DISCONNECT_SCO;
1785         hfp_connection->release_audio_connection = 1;
1786         return;
1787     }
1788 }
1789 
1790 uint8_t hfp_trigger_release_audio_connection(hfp_connection_t * hfp_connection){
1791     // called internally, NULL check already performed
1792     btstack_assert(hfp_connection != NULL);
1793     if (hfp_connection->state <= HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED){
1794         return ERROR_CODE_COMMAND_DISALLOWED;
1795     }
1796     switch (hfp_connection->state) {
1797         case HFP_W2_CONNECT_SCO:
1798             hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
1799             break;
1800         case HFP_W4_SCO_CONNECTED:
1801         case HFP_AUDIO_CONNECTION_ESTABLISHED:
1802             hfp_connection->release_audio_connection = 1;
1803             break;
1804         default:
1805             return ERROR_CODE_COMMAND_DISALLOWED;
1806     }
1807     return ERROR_CODE_SUCCESS;
1808 }
1809 
1810 static const struct link_settings {
1811     const uint16_t max_latency;
1812     const uint8_t  retransmission_effort;
1813     const uint16_t packet_types;
1814     const bool     eSCO;
1815     const uint8_t  codec;
1816 } hfp_link_settings [] = {
1817     { 0xffff, 0xff, SCO_PACKET_TYPES_HV1,  false, HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_D0
1818     { 0xffff, 0xff, SCO_PACKET_TYPES_HV3,  false, HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_D1
1819     { 0x0007, 0x01, SCO_PACKET_TYPES_EV3,  true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S1
1820     { 0x0007, 0x01, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S2
1821     { 0x000a, 0x01, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S3
1822     { 0x000c, 0x02, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S4
1823     { 0x0008, 0x02, SCO_PACKET_TYPES_EV3,  true,  HFP_CODEC_MSBC }, // HFP_LINK_SETTINGS_T1
1824     { 0x000d, 0x02, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_MSBC }  // HFP_LINK_SETTINGS_T2
1825 };
1826 
1827 void hfp_setup_synchronous_connection(hfp_connection_t * hfp_connection){
1828     // all packet types, fixed bandwidth
1829     int setting = hfp_connection->link_setting;
1830     log_info("hfp_setup_synchronous_connection using setting nr %u", setting);
1831     hfp_sco_establishment_active = hfp_connection;
1832     uint16_t sco_voice_setting = hci_get_sco_voice_setting();
1833     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1834 #ifdef ENABLE_BCM_PCM_WBS
1835         sco_voice_setting = 0x0063; // Transparent data, 16-bit for BCM controllers
1836 #else
1837         sco_voice_setting = 0x0043; // Transparent data, 8-bit otherwise
1838 #endif
1839     }
1840     // get packet types - bits 6-9 are 'don't allow'
1841     uint16_t packet_types = hfp_link_settings[setting].packet_types ^ 0x03c0;
1842     hci_send_cmd(&hci_setup_synchronous_connection, hfp_connection->acl_handle, 8000, 8000, hfp_link_settings[setting].max_latency,
1843         sco_voice_setting, hfp_link_settings[setting].retransmission_effort, packet_types);
1844 }
1845 
1846 void hfp_accept_synchronous_connection(hfp_connection_t * hfp_connection, bool incoming_eSCO){
1847 
1848     // remote supported feature eSCO is set if link type is eSCO
1849     // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
1850     uint16_t max_latency;
1851     uint8_t  retransmission_effort;
1852     uint16_t packet_types;
1853 
1854     if (incoming_eSCO && hci_extended_sco_link_supported() && hci_remote_esco_supported(hfp_connection->acl_handle)){
1855         max_latency = 0x000c;
1856         retransmission_effort = 0x02;
1857         // eSCO: EV3 and 2-EV3
1858         packet_types = 0x0048;
1859     } else {
1860         max_latency = 0xffff;
1861         retransmission_effort = 0xff;
1862         // sco: HV1 and HV3
1863         packet_types = 0x005;
1864     }
1865 
1866     // mSBC only allows for transparent data
1867     uint16_t sco_voice_setting = hci_get_sco_voice_setting();
1868     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1869 #ifdef ENABLE_BCM_PCM_WBS
1870         sco_voice_setting = 0x0063; // Transparent data, 16-bit for BCM controllers
1871 #else
1872         sco_voice_setting = 0x0043; // Transparent data, 8-bit otherwise
1873 #endif
1874     }
1875 
1876     // filter packet types
1877     packet_types &= hfp_get_sco_packet_types();
1878 
1879     // bits 6-9 are 'don't allow'
1880     packet_types ^= 0x3c0;
1881 
1882     log_info("HFP: sending hci_accept_connection_request, packet types 0x%04x, sco_voice_setting 0x%02x", packet_types, sco_voice_setting);
1883     hci_send_cmd(&hci_accept_synchronous_connection, hfp_connection->remote_addr, 8000, 8000, max_latency,
1884                  sco_voice_setting, retransmission_effort, packet_types);
1885 }
1886 
1887 #ifdef ENABLE_CC256X_ASSISTED_HFP
1888 void hfp_cc256x_prepare_for_sco(hfp_connection_t * hfp_connection){
1889     hfp_connection->cc256x_send_write_codec_config = true;
1890     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1891         hfp_connection->cc256x_send_wbs_associate = true;
1892     }
1893 }
1894 
1895 void hfp_cc256x_write_codec_config(hfp_connection_t * hfp_connection){
1896     uint32_t sample_rate_hz;
1897     uint16_t clock_rate_khz;
1898     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1899         clock_rate_khz = 512;
1900         sample_rate_hz = 16000;
1901     } else {
1902         clock_rate_khz = 256;
1903         sample_rate_hz = 8000;
1904     }
1905     uint8_t clock_direction = 0;        // master
1906     uint16_t frame_sync_duty_cycle = 0; // i2s with 50%
1907     uint8_t  frame_sync_edge = 1;       // rising edge
1908     uint8_t  frame_sync_polarity = 0;   // active high
1909     uint8_t  reserved = 0;
1910     uint16_t size = 16;
1911     uint16_t chan_1_offset = 1;
1912     uint16_t chan_2_offset = chan_1_offset + size;
1913     uint8_t  out_edge = 1;              // rising
1914     uint8_t  in_edge = 0;               // falling
1915     hci_send_cmd(&hci_ti_write_codec_config, clock_rate_khz, clock_direction, sample_rate_hz, frame_sync_duty_cycle,
1916                  frame_sync_edge, frame_sync_polarity, reserved,
1917                  size, chan_1_offset, out_edge, size, chan_1_offset, in_edge, reserved,
1918                  size, chan_2_offset, out_edge, size, chan_2_offset, in_edge, reserved);
1919 }
1920 #endif
1921 
1922 #ifdef ENABLE_BCM_PCM_WBS
1923 void hfp_bcm_prepare_for_sco(hfp_connection_t * hfp_connection){
1924     hfp_connection->bcm_send_write_i2spcm_interface_param = true;
1925     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1926         hfp_connection->bcm_send_enable_wbs = true;
1927     }
1928 }
1929 void hfp_bcm_write_i2spcm_interface_param(hfp_connection_t * hfp_connection){
1930     uint8_t sample_rate = (hfp_connection->negotiated_codec == HFP_CODEC_MSBC) ? 1 : 0;
1931     // i2s enable, master, 8/16 kHz, 512 kHz
1932     hci_send_cmd(&hci_bcm_write_i2spcm_interface_paramhci_bcm_write_i2spcm_interface_param, 1, 1, sample_rate, 2);
1933 }
1934 #endif
1935 
1936 void hfp_set_hf_callback(btstack_packet_handler_t callback){
1937     hfp_hf_callback = callback;
1938 }
1939 
1940 void hfp_set_ag_callback(btstack_packet_handler_t callback){
1941     hfp_ag_callback = callback;
1942 }
1943 
1944 void hfp_set_ag_rfcomm_packet_handler(btstack_packet_handler_t handler){
1945     hfp_ag_rfcomm_packet_handler = handler;
1946 }
1947 
1948 void hfp_set_hf_rfcomm_packet_handler(btstack_packet_handler_t handler){
1949     hfp_hf_rfcomm_packet_handler = handler;
1950 }
1951 
1952 void hfp_init(void){
1953     hfp_allowed_sco_packet_types = SCO_PACKET_TYPES_ALL;
1954 }
1955 
1956 void hfp_deinit(void){
1957     hfp_allowed_sco_packet_types = 0;
1958     hfp_connections = NULL;
1959     hfp_hf_callback = NULL;
1960     hfp_ag_callback = NULL;
1961     hfp_hf_rfcomm_packet_handler = NULL;
1962     hfp_ag_rfcomm_packet_handler = NULL;
1963     hfp_sco_establishment_active = NULL;
1964     (void) memset(&hfp_sdp_query_context, 0, sizeof(hfp_sdp_query_context_t));
1965     (void) memset(&hfp_sdp_query_request, 0, sizeof(btstack_context_callback_registration_t));
1966 }
1967 
1968 void hfp_set_sco_packet_types(uint16_t packet_types){
1969     hfp_allowed_sco_packet_types = packet_types;
1970 }
1971 
1972 uint16_t hfp_get_sco_packet_types(void){
1973     return hfp_allowed_sco_packet_types;
1974 }
1975 
1976 hfp_link_settings_t hfp_next_link_setting(hfp_link_settings_t current_setting, bool local_eSCO_supported, bool remote_eSCO_supported, bool eSCO_S4_supported, uint8_t negotiated_codec){
1977     int8_t setting = (int8_t) current_setting;
1978     bool can_use_eSCO = local_eSCO_supported && remote_eSCO_supported;
1979     while (setting > 0){
1980         setting--;
1981         // skip if eSCO required but not available
1982         if (hfp_link_settings[setting].eSCO && !can_use_eSCO) continue;
1983         // skip if S4 but not supported
1984         if ((setting == (int8_t) HFP_LINK_SETTINGS_S4) && !eSCO_S4_supported) continue;
1985         // skip wrong codec
1986         if ( hfp_link_settings[setting].codec != negotiated_codec) continue;
1987         // skip disabled packet types
1988         uint16_t required_packet_types = hfp_link_settings[setting].packet_types;
1989         uint16_t allowed_packet_types  = hfp_allowed_sco_packet_types;
1990         if ((required_packet_types & allowed_packet_types) == 0) continue;
1991 
1992         // found matching setting
1993         return (hfp_link_settings_t) setting;
1994     }
1995     return HFP_LINK_SETTINGS_NONE;
1996 }
1997 
1998 static hfp_link_settings_t hfp_next_link_setting_for_connection(hfp_link_settings_t current_setting, hfp_connection_t * hfp_connection, uint8_t eSCO_S4_supported){
1999     bool local_eSCO_supported  = hci_extended_sco_link_supported();
2000     bool remote_eSCO_supported = hci_remote_esco_supported(hfp_connection->acl_handle);
2001     uint8_t negotiated_codec   = hfp_connection->negotiated_codec;
2002     return  hfp_next_link_setting(current_setting, local_eSCO_supported, remote_eSCO_supported, eSCO_S4_supported, negotiated_codec);
2003 }
2004 
2005 void hfp_init_link_settings(hfp_connection_t * hfp_connection, uint8_t eSCO_S4_supported){
2006     // get highest possible link setting
2007     hfp_connection->link_setting = hfp_next_link_setting_for_connection(HFP_LINK_SETTINGS_NONE, hfp_connection, eSCO_S4_supported);
2008     log_info("hfp_init_link_settings: %u", hfp_connection->link_setting);
2009 }
2010 
2011 #define HFP_HF_RX_DEBUG_PRINT_LINE 80
2012 
2013 void hfp_log_rfcomm_message(const char * tag, uint8_t * packet, uint16_t size){
2014 #ifdef ENABLE_LOG_INFO
2015     // encode \n\r
2016     char printable[HFP_HF_RX_DEBUG_PRINT_LINE+2];
2017     int i = 0;
2018     int pos;
2019     for (pos=0 ; (pos < size) && (i < (HFP_HF_RX_DEBUG_PRINT_LINE - 3)) ; pos++){
2020         switch (packet[pos]){
2021             case '\n':
2022                 printable[i++] = '\\';
2023                 printable[i++] = 'n';
2024                 break;
2025             case '\r':
2026                 printable[i++] = '\\';
2027                 printable[i++] = 'r';
2028                 break;
2029             default:
2030                 printable[i++] = packet[pos];
2031                 break;
2032         }
2033     }
2034     printable[i] = 0;
2035     log_info("%s: '%s'", tag, printable);
2036 #endif
2037 }
2038