xref: /btstack/src/classic/hfp.c (revision 0e83ff1de7450f0484724c20bb379961742912cb)
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 BLUEKITCHEN
24  * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "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 
592     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
593     hfp_connection->sco_handle = HCI_CON_HANDLE_INVALID;
594 
595     hfp_reset_context_flags(hfp_connection);
596 
597     btstack_linked_list_add(&hfp_connections, (btstack_linked_item_t*)hfp_connection);
598     return hfp_connection;
599 }
600 
601 void hfp_finalize_connection_context(hfp_connection_t * hfp_connection){
602     btstack_linked_list_remove(&hfp_connections, (btstack_linked_item_t*) hfp_connection);
603     btstack_memory_hfp_connection_free(hfp_connection);
604 }
605 
606 static hfp_connection_t * hfp_create_connection(bd_addr_t bd_addr, hfp_role_t local_role){
607     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_bd_addr(bd_addr, local_role);
608     if (hfp_connection) return  hfp_connection;
609     hfp_connection = create_hfp_connection_context();
610     (void)memcpy(hfp_connection->remote_addr, bd_addr, 6);
611     hfp_connection->local_role = local_role;
612     log_info("Create HFP context %p: role %u, addr %s", hfp_connection, local_role, bd_addr_to_str(bd_addr));
613 
614     return hfp_connection;
615 }
616 
617 /* @param network.
618  * 0 == no ability to reject a call.
619  * 1 == ability to reject a call.
620  */
621 
622 /* @param suported_features
623  * HF bit 0: EC and/or NR function (yes/no, 1 = yes, 0 = no)
624  * HF bit 1: Call waiting or three-way calling(yes/no, 1 = yes, 0 = no)
625  * HF bit 2: CLI presentation capability (yes/no, 1 = yes, 0 = no)
626  * HF bit 3: Voice recognition activation (yes/no, 1= yes, 0 = no)
627  * HF bit 4: Remote volume control (yes/no, 1 = yes, 0 = no)
628  * HF bit 5: Wide band speech (yes/no, 1 = yes, 0 = no)
629  */
630  /* Bit position:
631  * AG bit 0: Three-way calling (yes/no, 1 = yes, 0 = no)
632  * AG bit 1: EC and/or NR function (yes/no, 1 = yes, 0 = no)
633  * AG bit 2: Voice recognition function (yes/no, 1 = yes, 0 = no)
634  * AG bit 3: In-band ring tone capability (yes/no, 1 = yes, 0 = no)
635  * AG bit 4: Attach a phone number to a voice tag (yes/no, 1 = yes, 0 = no)
636  * AG bit 5: Wide band speech (yes/no, 1 = yes, 0 = no)
637  */
638 
639 void hfp_create_sdp_record(uint8_t * service, uint32_t service_record_handle, uint16_t service_uuid, int rfcomm_channel_nr, const char * name){
640     uint8_t* attribute;
641     de_create_sequence(service);
642 
643     // 0x0000 "Service Record Handle"
644     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
645     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
646 
647     // 0x0001 "Service Class ID List"
648     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
649     attribute = de_push_sequence(service);
650     {
651         //  "UUID for Service"
652         de_add_number(attribute, DE_UUID, DE_SIZE_16, service_uuid);
653         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_GENERIC_AUDIO);
654     }
655     de_pop_sequence(service, attribute);
656 
657     // 0x0004 "Protocol Descriptor List"
658     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
659     attribute = de_push_sequence(service);
660     {
661         uint8_t* l2cpProtocol = de_push_sequence(attribute);
662         {
663             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
664         }
665         de_pop_sequence(attribute, l2cpProtocol);
666 
667         uint8_t* rfcomm = de_push_sequence(attribute);
668         {
669             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_RFCOMM);  // rfcomm_service
670             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
671         }
672         de_pop_sequence(attribute, rfcomm);
673     }
674     de_pop_sequence(service, attribute);
675 
676 
677     // 0x0005 "Public Browse Group"
678     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
679     attribute = de_push_sequence(service);
680     {
681         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
682     }
683     de_pop_sequence(service, attribute);
684 
685     // 0x0009 "Bluetooth Profile Descriptor List"
686     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
687     attribute = de_push_sequence(service);
688     {
689         uint8_t *sppProfile = de_push_sequence(attribute);
690         {
691             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_HANDSFREE);
692             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0108); // Verision 1.8
693         }
694         de_pop_sequence(attribute, sppProfile);
695     }
696     de_pop_sequence(service, attribute);
697 
698     // 0x0100 "Service Name"
699     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
700     de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
701 }
702 
703 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
704     UNUSED(packet_type);    // ok: handling own sdp events
705     UNUSED(channel);        // ok: no channel
706     UNUSED(size);           // ok: handling own sdp events
707 
708     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_bd_addr(hfp_sdp_query_context.remote_address, hfp_sdp_query_context.local_role);
709     if (hfp_connection == NULL) {
710         log_info("connection with %s and local role %d not found", hfp_sdp_query_context.remote_address, hfp_sdp_query_context.local_role);
711         return;
712     }
713 
714     switch (hci_event_packet_get_type(packet)){
715         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
716             hfp_connection->rfcomm_channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
717             break;
718         case SDP_EVENT_QUERY_COMPLETE:
719             if (hfp_connection->rfcomm_channel_nr > 0){
720                 hfp_connection->state = HFP_W4_RFCOMM_CONNECTED;
721                 btstack_packet_handler_t packet_handler;
722                 switch (hfp_connection->local_role){
723                     case HFP_ROLE_AG:
724                         packet_handler = hfp_ag_rfcomm_packet_handler;
725                         break;
726                     case HFP_ROLE_HF:
727                         packet_handler = hfp_hf_rfcomm_packet_handler;
728                         break;
729                     default:
730                         btstack_assert(false);
731                         return;
732                 }
733 
734                 rfcomm_create_channel(packet_handler, hfp_connection->remote_addr, hfp_connection->rfcomm_channel_nr, NULL);
735 
736             } else {
737                 hfp_connection->state = HFP_IDLE;
738                 uint8_t status = sdp_event_query_complete_get_status(packet);
739                 if (status == ERROR_CODE_SUCCESS){
740                     // report service not found
741                     status = SDP_SERVICE_NOT_FOUND;
742                 }
743                 hfp_emit_slc_connection_event(hfp_connection, status, HCI_CON_HANDLE_INVALID, hfp_connection->remote_addr);
744                 log_info("rfcomm service not found, status 0x%02x", status);
745             }
746 
747             // register the SDP Query request to check if there is another connection waiting for the query
748             // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
749             (void) sdp_client_register_query_callback(&hfp_sdp_query_request);
750             break;
751         default:
752             break;
753     }
754 }
755 
756 // returns 0 if unexpected error or no other link options remained, otherwise 1
757 static int hfp_handle_failed_sco_connection(uint8_t status){
758 
759     if (!hfp_sco_establishment_active){
760         log_info("(e)SCO Connection failed but not started by us");
761         return 0;
762     }
763 
764     log_info("(e)SCO Connection failed 0x%02x", status);
765     switch (status){
766         case ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE:
767         case ERROR_CODE_UNSPECIFIED_ERROR:
768         case ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES:
769             break;
770         default:
771             return 0;
772     }
773 
774     // note: eSCO_S4 supported flag not available, but it's only relevant for highest CVSD link setting (and the current failed)
775     hfp_link_settings_t next_setting = hfp_next_link_setting_for_connection(hfp_sco_establishment_active->link_setting, hfp_sco_establishment_active, false);
776 
777     // handle no valid setting found
778     if (next_setting == HFP_LINK_SETTINGS_NONE) {
779         if (hfp_sco_establishment_active->negotiated_codec == HFP_CODEC_MSBC){
780             log_info("T2/T1 failed, fallback to CVSD - D1");
781             hfp_sco_establishment_active->negotiated_codec = HFP_CODEC_CVSD;
782             hfp_sco_establishment_active->sco_for_msbc_failed = 1;
783             hfp_sco_establishment_active->ag_send_common_codec = true;
784             hfp_sco_establishment_active->link_setting = HFP_LINK_SETTINGS_D1;
785         } else {
786             // no other options
787             return 0;
788         }
789     }
790 
791     log_info("e)SCO Connection: try new link_setting %d", next_setting);
792     hfp_sco_establishment_active->establish_audio_connection = 1;
793     hfp_sco_establishment_active->link_setting = next_setting;
794     hfp_sco_establishment_active = NULL;
795     return 1;
796 }
797 
798 void hfp_handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, hfp_role_t local_role){
799     UNUSED(packet_type);
800     UNUSED(channel);    // ok: no channel
801     UNUSED(size);
802 
803     bd_addr_t event_addr;
804     hci_con_handle_t handle;
805     hfp_connection_t * hfp_connection = NULL;
806     uint8_t status;
807 
808     log_debug("HFP HCI event handler type %u, event type %x, size %u", packet_type, hci_event_packet_get_type(packet), size);
809 
810     switch (hci_event_packet_get_type(packet)) {
811 
812         case HCI_EVENT_CONNECTION_REQUEST:
813             switch(hci_event_connection_request_get_link_type(packet)){
814                 case 0: //  SCO
815                 case 2: // eSCO
816                     hci_event_connection_request_get_bd_addr(packet, event_addr);
817                     hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
818                     if (!hfp_connection) break;
819                     if (hci_event_connection_request_get_link_type(packet) == 2){
820                         hfp_connection->accept_sco = 2;
821                     } else {
822                         hfp_connection->accept_sco = 1;
823                     }
824 #ifdef ENABLE_CC256X_ASSISTED_HFP
825                     hfp_cc256x_prepare_for_sco(hfp_connection);
826 #endif
827 #ifdef ENABLE_BCM_PCM_WBS
828                     hfp_bcm_prepare_for_sco(hfp_connection);
829 #endif
830 #ifdef ENABLE_RTK_PCM_WBS
831                     hfp_connection->rtk_send_sco_config = true;
832 #endif
833                     log_info("accept sco %u\n", hfp_connection->accept_sco);
834                     hfp_sco_establishment_active = hfp_connection;
835                     break;
836                 default:
837                     break;
838             }
839             break;
840 
841         case HCI_EVENT_COMMAND_STATUS:
842             if (hci_event_command_status_get_command_opcode(packet) == hci_setup_synchronous_connection.opcode) {
843                 if (hfp_sco_establishment_active == NULL) break;
844                 status = hci_event_command_status_get_status(packet);
845                 if (status == ERROR_CODE_SUCCESS) break;
846 
847                 hfp_connection = hfp_sco_establishment_active;
848                 if (hfp_handle_failed_sco_connection(status)) break;
849                 hfp_connection->establish_audio_connection = 0;
850                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
851                 hfp_emit_sco_event(hfp_connection, status, 0, hfp_connection->remote_addr, hfp_connection->negotiated_codec);
852             }
853             break;
854 
855         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
856             if (hfp_sco_establishment_active == NULL) break;
857             hci_event_synchronous_connection_complete_get_bd_addr(packet, event_addr);
858             hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
859             if (!hfp_connection) {
860                 log_error("HFP: connection does not exist for remote with addr %s.", bd_addr_to_str(event_addr));
861                 return;
862             }
863 
864             status = hci_event_synchronous_connection_complete_get_status(packet);
865             if (status != ERROR_CODE_SUCCESS){
866                 hfp_connection->accept_sco = 0;
867                 if (hfp_handle_failed_sco_connection(status)) break;
868 
869                 hfp_connection->establish_audio_connection = 0;
870                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
871                 hfp_emit_sco_event(hfp_connection, status, 0, event_addr, hfp_connection->negotiated_codec);
872                 break;
873             }
874 
875             uint16_t sco_handle = hci_event_synchronous_connection_complete_get_handle(packet);
876             uint8_t  link_type = hci_event_synchronous_connection_complete_get_link_type(packet);
877             uint8_t  transmission_interval = hci_event_synchronous_connection_complete_get_transmission_interval(packet);  // measured in slots
878             uint8_t  retransmission_interval = hci_event_synchronous_connection_complete_get_retransmission_interval(packet);// measured in slots
879             uint16_t rx_packet_length = hci_event_synchronous_connection_complete_get_rx_packet_length(packet); // measured in bytes
880             uint16_t tx_packet_length = hci_event_synchronous_connection_complete_get_tx_packet_length(packet); // measured in bytes
881 
882             switch (link_type){
883                 case 0x00:
884                     log_info("SCO Connection established.");
885                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
886                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
887                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
888                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
889                     break;
890                 case 0x02:
891                     log_info("eSCO Connection established. \n");
892                     break;
893                 default:
894                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
895                     break;
896             }
897 
898             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
899                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)\n", sco_handle,
900                  bd_addr_to_str(event_addr), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length,
901                  hci_event_synchronous_connection_complete_get_air_mode(packet));
902 
903             if (hfp_connection->state == HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
904                 log_info("SCO about to disconnect: HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN");
905                 hfp_connection->state = HFP_W2_DISCONNECT_SCO;
906                 break;
907             }
908             hfp_connection->sco_handle = sco_handle;
909             hfp_connection->establish_audio_connection = 0;
910 
911             hfp_connection->state = HFP_AUDIO_CONNECTION_ESTABLISHED;
912 
913             switch (hfp_connection->vra_state){
914                 case HFP_VRA_VOICE_RECOGNITION_ACTIVATED:
915                     hfp_connection->ag_audio_connection_opened_before_vra = false;
916                     break;
917                 default:
918                     hfp_connection->ag_audio_connection_opened_before_vra = true;
919                     break;
920             }
921             hfp_emit_sco_event(hfp_connection, status, sco_handle, event_addr, hfp_connection->negotiated_codec);
922             break;
923         }
924 
925         case HCI_EVENT_DISCONNECTION_COMPLETE:
926             handle = little_endian_read_16(packet,3);
927             hfp_connection = get_hfp_connection_context_for_sco_handle(handle, local_role);
928 
929             if (!hfp_connection) break;
930 
931 #ifdef ENABLE_CC256X_ASSISTED_HFP
932             hfp_connection->cc256x_send_wbs_disassociate = true;
933 #endif
934 #ifdef ENABLE_BCM_PCM_WBS
935             hfp_connection->bcm_send_disable_wbs = true;
936 #endif
937             if (hfp_connection->sco_handle == handle){
938                 hfp_connection->sco_handle = HCI_CON_HANDLE_INVALID;
939                 hfp_connection->release_audio_connection = 0;
940                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
941                 hfp_emit_audio_connection_released(hfp_connection, handle);
942 
943                 hfp_connection->ag_audio_connection_opened_before_vra = false;
944 
945                 if (hfp_connection->acl_handle == HCI_CON_HANDLE_INVALID){
946                     hfp_reset_voice_recognition(hfp_connection);
947                     hfp_emit_event(hfp_connection, HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_RELEASED, 0);
948                     hfp_finalize_connection_context(hfp_connection);
949                     break;
950                 } else if (hfp_connection->release_slc_connection == 1){
951                     hfp_connection->release_slc_connection = 0;
952                     hfp_connection->state = HFP_W2_DISCONNECT_RFCOMM;
953                     rfcomm_disconnect(hfp_connection->acl_handle);
954                 }
955             }
956 
957             if (hfp_connection->state == HFP_W4_SCO_DISCONNECTED_TO_SHUTDOWN){
958                 // RFCOMM already closed -> remote power off
959 #if defined(ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
960                 hfp_connection->state = HFP_W4_WBS_SHUTDOWN;
961 #else
962                 hfp_finalize_connection_context(hfp_connection);
963 #endif
964                 break;
965             }
966             break;
967 
968         default:
969             break;
970     }
971 }
972 
973 
974 void hfp_handle_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, hfp_role_t local_role){
975     UNUSED(packet_type);
976     UNUSED(channel);    // ok: no channel
977     UNUSED(size);
978 
979     bd_addr_t event_addr;
980     uint16_t rfcomm_cid;
981     hfp_connection_t * hfp_connection = NULL;
982     uint8_t status;
983 
984     log_debug("HFP packet_handler type %u, event type %x, size %u", packet_type, hci_event_packet_get_type(packet), size);
985 
986     switch (hci_event_packet_get_type(packet)) {
987 
988         case RFCOMM_EVENT_INCOMING_CONNECTION:
989             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
990             rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr);
991             hfp_connection = hfp_create_connection(event_addr, local_role);
992             if (!hfp_connection){
993                 log_info("hfp: no memory to accept incoming connection - decline");
994                 rfcomm_decline_connection(rfcomm_event_incoming_connection_get_rfcomm_cid(packet));
995                 return;
996             }
997             if (hfp_connection->state != HFP_IDLE) {
998                 log_error("hfp: incoming connection but not idle, reject");
999                 rfcomm_decline_connection(rfcomm_event_incoming_connection_get_rfcomm_cid(packet));
1000                 return;
1001             }
1002 
1003             hfp_connection->rfcomm_cid = rfcomm_event_incoming_connection_get_rfcomm_cid(packet);
1004             hfp_connection->state = HFP_W4_RFCOMM_CONNECTED;
1005             rfcomm_accept_connection(hfp_connection->rfcomm_cid);
1006             break;
1007 
1008         case RFCOMM_EVENT_CHANNEL_OPENED:
1009             rfcomm_event_channel_opened_get_bd_addr(packet, event_addr);
1010 
1011             hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
1012             btstack_assert(hfp_connection != NULL);
1013 
1014             if (hfp_connection->state != HFP_W4_RFCOMM_CONNECTED){
1015                 break;
1016             }
1017 
1018             status = rfcomm_event_channel_opened_get_status(packet);
1019             if (status != ERROR_CODE_SUCCESS) {
1020                 hfp_emit_slc_connection_event(hfp_connection, status, rfcomm_event_channel_opened_get_con_handle(packet), event_addr);
1021                 hfp_finalize_connection_context(hfp_connection);
1022                 break;
1023             }
1024 
1025             hfp_connection->acl_handle = rfcomm_event_channel_opened_get_con_handle(packet);
1026             hfp_connection->rfcomm_cid = rfcomm_event_channel_opened_get_rfcomm_cid(packet);
1027             hfp_connection->rfcomm_mtu = rfcomm_event_channel_opened_get_max_frame_size(packet);
1028             bd_addr_copy(hfp_connection->remote_addr, event_addr);
1029             hfp_connection->state = HFP_EXCHANGE_SUPPORTED_FEATURES;
1030 
1031             rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1032             break;
1033 
1034         case RFCOMM_EVENT_CHANNEL_CLOSED:
1035             rfcomm_cid = little_endian_read_16(packet,2);
1036             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
1037             if (!hfp_connection) break;
1038             switch (hfp_connection->state){
1039                 case HFP_W4_RFCOMM_DISCONNECTED_AND_RESTART:
1040                     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
1041                     hfp_connection->state = HFP_IDLE;
1042                     hfp_establish_service_level_connection(hfp_connection->remote_addr, hfp_connection->service_uuid, local_role);
1043                     break;
1044 
1045                 case HFP_AUDIO_CONNECTION_ESTABLISHED:
1046                     // service connection was released, this implicitly releases audio connection as well
1047                     hfp_connection->release_audio_connection = 0;
1048                     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
1049                     hfp_connection->state = HFP_W4_SCO_DISCONNECTED_TO_SHUTDOWN;
1050                     gap_disconnect(hfp_connection->sco_handle);
1051                     break;
1052 
1053                 default:
1054                     // regular case
1055                     hfp_reset_voice_recognition(hfp_connection);
1056                     hfp_emit_event(hfp_connection, HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_RELEASED, 0);
1057                     hfp_finalize_connection_context(hfp_connection);
1058                     break;
1059             }
1060             break;
1061 
1062         default:
1063             break;
1064     }
1065 }
1066 // translates command string into hfp_command_t CMD
1067 
1068 typedef struct {
1069     const char * command;
1070     hfp_command_t command_id;
1071 } hfp_command_entry_t;
1072 
1073 static hfp_command_entry_t hfp_ag_commmand_table[] = {
1074     { "AT+BAC=",   HFP_CMD_AVAILABLE_CODECS },
1075     { "AT+BCC",    HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP },
1076     { "AT+BCS=",   HFP_CMD_HF_CONFIRMED_CODEC },
1077     { "AT+BIA=",   HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE, }, // +BIA:<enabled>,,<enabled>,,,<enabled>
1078     { "AT+BIEV=",  HFP_CMD_HF_INDICATOR_STATUS },
1079     { "AT+BIND=",  HFP_CMD_LIST_GENERIC_STATUS_INDICATORS },
1080     { "AT+BIND=?", HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS },
1081     { "AT+BIND?",  HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE },
1082     { "AT+BINP=",  HFP_CMD_HF_REQUEST_PHONE_NUMBER },
1083     { "AT+BLDN",   HFP_CMD_REDIAL_LAST_NUMBER },
1084     { "AT+BRSF=",  HFP_CMD_SUPPORTED_FEATURES },
1085     { "AT+BTRH=",  HFP_CMD_RESPONSE_AND_HOLD_COMMAND },
1086     { "AT+BTRH?",  HFP_CMD_RESPONSE_AND_HOLD_QUERY },
1087     { "AT+BVRA=",  HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION },
1088     { "AT+CCWA=",  HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION},
1089     { "AT+CHLD=",  HFP_CMD_CALL_HOLD },
1090     { "AT+CHLD=?", HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES },
1091     { "AT+CHUP",   HFP_CMD_HANG_UP_CALL },
1092     { "AT+CIND=?", HFP_CMD_RETRIEVE_AG_INDICATORS },
1093     { "AT+CIND?",  HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS },
1094     { "AT+CLCC",   HFP_CMD_LIST_CURRENT_CALLS },
1095     { "AT+CLIP=",  HFP_CMD_ENABLE_CLIP},
1096     { "AT+CMEE=",  HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR},
1097     { "AT+CMER=",  HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE },
1098     { "AT+CNUM",   HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION },
1099     { "AT+COPS=",  HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT },
1100     { "AT+COPS?",  HFP_CMD_QUERY_OPERATOR_SELECTION_NAME },
1101     { "AT+NREC=",  HFP_CMD_TURN_OFF_EC_AND_NR, },
1102     { "AT+VGM=",   HFP_CMD_SET_MICROPHONE_GAIN },
1103     { "AT+VGS=",   HFP_CMD_SET_SPEAKER_GAIN },
1104     { "AT+VTS=",   HFP_CMD_TRANSMIT_DTMF_CODES },
1105     { "ATA",       HFP_CMD_CALL_ANSWERED },
1106 };
1107 
1108 static hfp_command_entry_t hfp_hf_commmand_table[] = {
1109     { "+BCS:",  HFP_CMD_AG_SUGGESTED_CODEC },
1110     { "+BIND:", HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS },
1111     { "+BINP",  HFP_CMD_AG_SENT_PHONE_NUMBER },
1112     { "+BRSF:", HFP_CMD_SUPPORTED_FEATURES },
1113     { "+BSIR:", HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING },
1114     { "+BTRH:", HFP_CMD_RESPONSE_AND_HOLD_STATUS },
1115     { "+BVRA:", HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION },
1116     { "+CCWA:", HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE, },
1117     { "+CHLD:", HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES },
1118     { "+CIEV:", HFP_CMD_TRANSFER_AG_INDICATOR_STATUS},
1119     { "+CIND:", HFP_CMD_RETRIEVE_AG_INDICATORS_GENERIC },
1120     { "+CLCC:", HFP_CMD_LIST_CURRENT_CALLS },
1121     { "+CLIP:", HFP_CMD_AG_SENT_CLIP_INFORMATION },
1122     { "+CME ERROR:", HFP_CMD_EXTENDED_AUDIO_GATEWAY_ERROR },
1123     { "+CNUM:", HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION},
1124     { "+COPS:", HFP_CMD_QUERY_OPERATOR_SELECTION_NAME },
1125     { "+VGM:",  HFP_CMD_SET_MICROPHONE_GAIN },
1126     { "+VGM=",  HFP_CMD_SET_MICROPHONE_GAIN },
1127     { "+VGS:",  HFP_CMD_SET_SPEAKER_GAIN},
1128     { "+VGS=",  HFP_CMD_SET_SPEAKER_GAIN},
1129     { "ERROR",  HFP_CMD_ERROR},
1130     { "NOP",    HFP_CMD_NONE}, // dummy command used by unit tests
1131     { "OK",     HFP_CMD_OK },
1132     { "RING",   HFP_CMD_RING },
1133 };
1134 
1135 static hfp_command_t parse_command(const char * line_buffer, int isHandsFree){
1136 
1137     // table lookup based on role
1138     uint16_t num_entries;
1139     hfp_command_entry_t * table;
1140     if (isHandsFree == 0){
1141         table = hfp_ag_commmand_table;
1142         num_entries = sizeof(hfp_ag_commmand_table) / sizeof(hfp_command_entry_t);
1143     } else {
1144         table = hfp_hf_commmand_table;
1145         num_entries = sizeof(hfp_hf_commmand_table) / sizeof(hfp_command_entry_t);
1146     }
1147     // binary search
1148     uint16_t left = 0;
1149     uint16_t right = num_entries - 1;
1150     while (left <= right){
1151         uint16_t middle = left + (right - left) / 2;
1152         hfp_command_entry_t *entry = &table[middle];
1153         int match = strcmp(line_buffer, entry->command);
1154         if (match < 0){
1155             // search term is lower than middle element
1156             if (right == 0) break;
1157             right = middle - 1;
1158         } else if (match == 0){
1159             return entry->command_id;
1160         } else {
1161             // search term is higher than middle element
1162             left = middle + 1;
1163         }
1164     }
1165 
1166     // note: if parser in CMD_HEADER state would treats digits and maybe '+' as separator, match on "ATD" would work.
1167     // note: phone number is currently expected in line_buffer[3..]
1168     // prefix match on 'ATD', AG only
1169     if ((isHandsFree == 0) && (strncmp(line_buffer, HFP_CALL_PHONE_NUMBER, strlen(HFP_CALL_PHONE_NUMBER)) == 0)){
1170         return HFP_CMD_CALL_PHONE_NUMBER;
1171     }
1172 
1173     // Valid looking, but unknown commands/responses
1174     if ((isHandsFree == 0) && (strncmp(line_buffer, "AT+", 3) == 0)){
1175         return HFP_CMD_UNKNOWN;
1176     }
1177 
1178     if ((isHandsFree != 0) && (strncmp(line_buffer, "+", 1) == 0)){
1179         return HFP_CMD_UNKNOWN;
1180     }
1181 
1182     return HFP_CMD_NONE;
1183 }
1184 
1185 static void hfp_parser_store_byte(hfp_connection_t * hfp_connection, uint8_t byte){
1186     if ((hfp_connection->line_size + 1) >= HFP_MAX_VR_TEXT_SIZE) return;
1187     hfp_connection->line_buffer[hfp_connection->line_size++] = byte;
1188     hfp_connection->line_buffer[hfp_connection->line_size] = 0;
1189 }
1190 static int hfp_parser_is_buffer_empty(hfp_connection_t * hfp_connection){
1191     return hfp_connection->line_size == 0;
1192 }
1193 
1194 static int hfp_parser_is_end_of_line(uint8_t byte){
1195     return (byte == '\n') || (byte == '\r');
1196 }
1197 
1198 static void hfp_parser_reset_line_buffer(hfp_connection_t *hfp_connection) {
1199     hfp_connection->line_size = 0;
1200     // hfp_connection->line_buffer[0] = 0;
1201 }
1202 
1203 static void hfp_parser_store_if_token(hfp_connection_t * hfp_connection, uint8_t byte){
1204     switch (byte){
1205         case ',':
1206 		case '-':
1207         case ';':
1208         case '(':
1209         case ')':
1210         case '\n':
1211         case '\r':
1212             break;
1213         default:
1214             hfp_parser_store_byte(hfp_connection, byte);
1215             break;
1216     }
1217 }
1218 
1219 static bool hfp_parser_is_separator( uint8_t byte){
1220     switch (byte){
1221         case ',':
1222 		case '-':
1223         case ';':
1224         case '\n':
1225         case '\r':
1226             return true;
1227         default:
1228             return false;
1229     }
1230 }
1231 
1232 static bool hfp_parse_byte(hfp_connection_t * hfp_connection, uint8_t byte, int isHandsFree){
1233 
1234     // handle doubles quotes
1235     if (byte == '"'){
1236         hfp_connection->parser_quoted = !hfp_connection->parser_quoted;
1237         return true;
1238     }
1239     if (hfp_connection->parser_quoted) {
1240         hfp_parser_store_byte(hfp_connection, byte);
1241         return true;
1242     }
1243 
1244     // ignore spaces outside command or double quotes (required e.g. for '+CME ERROR:..") command
1245     if ((byte == ' ') && (hfp_connection->parser_state != HFP_PARSER_CMD_HEADER)) return true;
1246 
1247     bool processed = true;
1248 
1249     switch (hfp_connection->parser_state) {
1250         case HFP_PARSER_CMD_HEADER:
1251             switch (byte) {
1252                 case '\n':
1253                 case '\r':
1254                 case ';':
1255                     // ignore separator
1256                     break;
1257                 case ':':
1258                 case '?':
1259                     // store separator
1260                     hfp_parser_store_byte(hfp_connection, byte);
1261                     break;
1262                 case '=':
1263                     // equal sign: remember and wait for next char to decided between '=?' and '=\?'
1264                     hfp_connection->found_equal_sign = true;
1265                     hfp_parser_store_byte(hfp_connection, byte);
1266                     return true;
1267                 default:
1268                     // store if not lookahead
1269                     if (!hfp_connection->found_equal_sign) {
1270                         hfp_parser_store_byte(hfp_connection, byte);
1271                         return true;
1272                     }
1273                     // mark as lookahead
1274                     processed = false;
1275                     break;
1276             }
1277 
1278             // ignore empty tokens
1279             if (hfp_parser_is_buffer_empty(hfp_connection)) return true;
1280 
1281             // parse
1282             hfp_connection->command = parse_command((char *)hfp_connection->line_buffer, isHandsFree);
1283 
1284             // pick +CIND version based on connection state: descriptions during SLC vs. states later
1285             if (hfp_connection->command == HFP_CMD_RETRIEVE_AG_INDICATORS_GENERIC){
1286                 switch(hfp_connection->state){
1287                     case HFP_W4_RETRIEVE_INDICATORS_STATUS:
1288                         hfp_connection->command = HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS;
1289                         break;
1290                     case HFP_W4_RETRIEVE_INDICATORS:
1291                         hfp_connection->command = HFP_CMD_RETRIEVE_AG_INDICATORS;
1292                         break;
1293                     default:
1294                         hfp_connection->command = HFP_CMD_UNKNOWN;
1295                         break;
1296                 }
1297             }
1298 
1299             log_info("command string '%s', handsfree %u -> cmd id %u", (char *)hfp_connection->line_buffer, isHandsFree, hfp_connection->command);
1300 
1301             // next state
1302             hfp_connection->found_equal_sign = false;
1303             hfp_parser_reset_line_buffer(hfp_connection);
1304             hfp_connection->parser_state = HFP_PARSER_CMD_SEQUENCE;
1305 
1306             return processed;
1307 
1308         case HFP_PARSER_CMD_SEQUENCE:
1309             // handle empty fields
1310             if ((byte == ',' ) && (hfp_connection->line_size == 0)){
1311                 hfp_connection->line_buffer[0] = 0;
1312                 hfp_connection->ignore_value = 1;
1313                 parse_sequence(hfp_connection);
1314                 return true;
1315             }
1316 
1317             hfp_parser_store_if_token(hfp_connection, byte);
1318             if (!hfp_parser_is_separator(byte)) return true;
1319 
1320             // ignore empty tokens
1321             switch (hfp_connection->command){
1322                 case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
1323                     // don't ignore empty string
1324                     break;
1325                 default:
1326                     if (hfp_parser_is_buffer_empty(hfp_connection) && (hfp_connection->ignore_value == 0)) {
1327                         return true;
1328                     }
1329                     break;
1330             }
1331 
1332             parse_sequence(hfp_connection);
1333 
1334             hfp_parser_reset_line_buffer(hfp_connection);
1335 
1336             switch (hfp_connection->command){
1337                 case HFP_CMD_AG_SENT_PHONE_NUMBER:
1338                 case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1339                 case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1340                 case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1341                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1342                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1343                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1344                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1345                 case HFP_CMD_HF_INDICATOR_STATUS:
1346                     hfp_connection->parser_state = HFP_PARSER_SECOND_ITEM;
1347                     break;
1348                 default:
1349                     break;
1350             }
1351             return true;
1352 
1353         case HFP_PARSER_SECOND_ITEM:
1354 
1355             hfp_parser_store_if_token(hfp_connection, byte);
1356             if (!hfp_parser_is_separator(byte)) return true;
1357 
1358             switch (hfp_connection->command){
1359                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1360                     log_info("format %s, ", hfp_connection->line_buffer);
1361                     hfp_connection->network_operator.format =  btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1362                     break;
1363                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1364                     log_info("format %s \n", hfp_connection->line_buffer);
1365                     hfp_connection->network_operator.format =  btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1366                     break;
1367                 case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
1368                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
1369                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1370                     hfp_connection->generic_status_indicators[hfp_connection->parser_item_index].state = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1371                     break;
1372                 case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1373                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].status = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1374                     log_info("%d \n", hfp_connection->ag_indicators[hfp_connection->parser_item_index].status);
1375                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].status_changed = 1;
1376                     break;
1377                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1378                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].min_range = btstack_atoi((char *)hfp_connection->line_buffer);
1379                     log_info("%s, ", hfp_connection->line_buffer);
1380                     break;
1381                 case HFP_CMD_AG_SENT_PHONE_NUMBER:
1382                 case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1383                 case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1384                     hfp_connection->bnip_type = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1385                     break;
1386                 case HFP_CMD_HF_INDICATOR_STATUS:
1387                     hfp_connection->parser_indicator_value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1388                     break;
1389                 default:
1390                     break;
1391             }
1392 
1393             hfp_parser_reset_line_buffer(hfp_connection);
1394 
1395             hfp_connection->parser_state = HFP_PARSER_THIRD_ITEM;
1396 
1397             return true;
1398 
1399         case HFP_PARSER_THIRD_ITEM:
1400 
1401             hfp_parser_store_if_token(hfp_connection, byte);
1402             if (!hfp_parser_is_separator(byte)) return true;
1403 
1404             switch (hfp_connection->command){
1405                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1406                     strncpy(hfp_connection->network_operator.name, (char *)hfp_connection->line_buffer, HFP_MAX_NETWORK_OPERATOR_NAME_SIZE);
1407                     hfp_connection->network_operator.name[HFP_MAX_NETWORK_OPERATOR_NAME_SIZE - 1] = 0;
1408                     log_info("name %s\n", hfp_connection->line_buffer);
1409                     break;
1410                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1411                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].max_range = btstack_atoi((char *)hfp_connection->line_buffer);
1412                     hfp_next_indicators_index(hfp_connection);
1413                     hfp_connection->ag_indicators_nr = hfp_connection->parser_item_index;
1414                     log_info("%s)\n", hfp_connection->line_buffer);
1415                     break;
1416                 default:
1417                     break;
1418             }
1419 
1420             hfp_parser_reset_line_buffer(hfp_connection);
1421 
1422             if (hfp_connection->command == HFP_CMD_RETRIEVE_AG_INDICATORS){
1423                 hfp_connection->parser_state = HFP_PARSER_CMD_SEQUENCE;
1424             } else {
1425                 hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
1426             }
1427             return true;
1428 
1429         default:
1430             btstack_assert(false);
1431             return true;
1432     }
1433 }
1434 
1435 void hfp_parse(hfp_connection_t * hfp_connection, uint8_t byte, int isHandsFree){
1436     bool processed = false;
1437     while (!processed){
1438         processed = hfp_parse_byte(hfp_connection, byte, isHandsFree);
1439     }
1440     // reset parser state on end-of-line
1441     if (hfp_parser_is_end_of_line(byte)){
1442         hfp_connection->parser_item_index = 0;
1443         hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
1444     }
1445 }
1446 
1447 static void parse_sequence(hfp_connection_t * hfp_connection){
1448     int value;
1449     switch (hfp_connection->command){
1450         case HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS:
1451             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1452             int i;
1453             switch (hfp_connection->parser_item_index){
1454                 case 0:
1455                     for (i=0;i<hfp_connection->generic_status_indicators_nr;i++){
1456                         if (hfp_connection->generic_status_indicators[i].uuid == value){
1457                             hfp_connection->parser_indicator_index = i;
1458                             break;
1459                         }
1460                     }
1461                     break;
1462                 case 1:
1463                     if (hfp_connection->parser_indicator_index <0) break;
1464                     hfp_connection->generic_status_indicators[hfp_connection->parser_indicator_index].state = value;
1465                     log_info("HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS set indicator at index %u, to %u\n",
1466                      hfp_connection->parser_item_index, value);
1467                     break;
1468                 default:
1469                     break;
1470             }
1471             hfp_next_indicators_index(hfp_connection);
1472             break;
1473 
1474         case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
1475             switch(hfp_connection->parser_item_index){
1476                 case 0:
1477                     // <alpha>: This optional field is not supported, and shall be left blank.
1478                     break;
1479                 case 1:
1480                     // <number>: Quoted string containing the phone number in the format specified by <type>.
1481                     strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1482                     hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1483                     break;
1484                 case 2:
1485                     /*
1486                       <type> field specifies the format of the phone number provided, and can be one of the following values:
1487                       - 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.
1488                      - 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.
1489                      - values 160-175: National number. No prefix nor escape digits included.
1490                      */
1491                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1492                     hfp_connection->bnip_type = value;
1493                     break;
1494                 case 3:
1495                     // <speed>: This optional field is not supported, and shall be left blank.
1496                     break;
1497                 case 4:
1498                     // <service>: Indicates which service this phone number relates to. Shall be either 4 (voice) or 5 (fax).
1499                 default:
1500                     break;
1501             }
1502             // index > 2 are ignored in switch above
1503             hfp_connection->parser_item_index++;
1504             break;
1505         case HFP_CMD_LIST_CURRENT_CALLS:
1506             switch(hfp_connection->parser_item_index){
1507                 case 0:
1508                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1509                     hfp_connection->clcc_idx = value;
1510                     break;
1511                 case 1:
1512                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1513                     hfp_connection->clcc_dir = value;
1514                     break;
1515                 case 2:
1516                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1517                     hfp_connection->clcc_status = value;
1518                     break;
1519                 case 3:
1520                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1521                     hfp_connection->clcc_mode = value;
1522                     break;
1523                 case 4:
1524                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1525                     hfp_connection->clcc_mpty = value;
1526                     break;
1527                 case 5:
1528                     strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1529                     hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1530                     break;
1531                 case 6:
1532                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1533                     hfp_connection->bnip_type = value;
1534                     break;
1535                 default:
1536                     break;
1537             }
1538             // index > 6 are ignored in switch above
1539             hfp_connection->parser_item_index++;
1540             break;
1541         case HFP_CMD_SET_MICROPHONE_GAIN:
1542             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1543             hfp_connection->microphone_gain = value;
1544             log_info("hfp parse HFP_CMD_SET_MICROPHONE_GAIN %d\n", value);
1545             break;
1546         case HFP_CMD_SET_SPEAKER_GAIN:
1547             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1548             hfp_connection->speaker_gain = value;
1549             log_info("hfp parse HFP_CMD_SET_SPEAKER_GAIN %d\n", value);
1550             break;
1551         case HFP_CMD_TURN_OFF_EC_AND_NR:
1552             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1553             hfp_connection->ag_echo_and_noise_reduction = value;
1554             log_info("hfp parse HFP_CMD_TURN_OFF_EC_AND_NR %d\n", value);
1555             break;
1556         case HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING:
1557             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1558             hfp_connection->remote_supported_features = store_bit(hfp_connection->remote_supported_features, HFP_AGSF_IN_BAND_RING_TONE, value);
1559             log_info("hfp parse HFP_CHANGE_IN_BAND_RING_TONE_SETTING %d\n", value);
1560             break;
1561         case HFP_CMD_HF_CONFIRMED_CODEC:
1562             hfp_connection->codec_confirmed = btstack_atoi((char*)hfp_connection->line_buffer);
1563             log_info("hfp parse HFP_CMD_HF_CONFIRMED_CODEC %d\n", hfp_connection->codec_confirmed);
1564             break;
1565         case HFP_CMD_AG_SUGGESTED_CODEC:
1566             hfp_connection->suggested_codec = btstack_atoi((char*)hfp_connection->line_buffer);
1567             log_info("hfp parse HFP_CMD_AG_SUGGESTED_CODEC %d\n", hfp_connection->suggested_codec);
1568             break;
1569         case HFP_CMD_SUPPORTED_FEATURES:
1570             hfp_connection->remote_supported_features = btstack_atoi((char*)hfp_connection->line_buffer);
1571             log_info("Parsed supported feature %d\n", (int) hfp_connection->remote_supported_features);
1572             break;
1573         case HFP_CMD_AVAILABLE_CODECS:
1574             log_info("Parsed codec %s\n", hfp_connection->line_buffer);
1575             hfp_connection->remote_codecs[hfp_connection->parser_item_index] = (uint16_t)btstack_atoi((char*)hfp_connection->line_buffer);
1576             hfp_next_codec_index(hfp_connection);
1577             hfp_connection->remote_codecs_nr = hfp_connection->parser_item_index;
1578             break;
1579         case HFP_CMD_RETRIEVE_AG_INDICATORS:
1580             strncpy((char *)hfp_connection->ag_indicators[hfp_connection->parser_item_index].name,  (char *)hfp_connection->line_buffer, HFP_MAX_INDICATOR_DESC_SIZE);
1581             hfp_connection->ag_indicators[hfp_connection->parser_item_index].name[HFP_MAX_INDICATOR_DESC_SIZE-1] = 0;
1582             hfp_connection->ag_indicators[hfp_connection->parser_item_index].index = hfp_connection->parser_item_index+1;
1583             log_info("Indicator %d: %s (", hfp_connection->ag_indicators_nr+1, hfp_connection->line_buffer);
1584             break;
1585         case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
1586             log_info("Parsed Indicator %d with status: %s\n", hfp_connection->parser_item_index+1, hfp_connection->line_buffer);
1587             hfp_connection->ag_indicators[hfp_connection->parser_item_index].status = btstack_atoi((char *) hfp_connection->line_buffer);
1588             hfp_next_indicators_index(hfp_connection);
1589             break;
1590         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
1591             hfp_next_indicators_index(hfp_connection);
1592             if (hfp_connection->parser_item_index != 4) break;
1593             log_info("Parsed Enable indicators: %s\n", hfp_connection->line_buffer);
1594             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1595             hfp_connection->enable_status_update_for_ag_indicators = (uint8_t) value;
1596             break;
1597         case HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES:
1598             log_info("Parsed Support call hold: %s\n", hfp_connection->line_buffer);
1599             if (hfp_connection->line_size > 2 ) break;
1600             memcpy((char *)hfp_connection->remote_call_services[hfp_connection->remote_call_services_index].name, (char *)hfp_connection->line_buffer, HFP_CALL_SERVICE_SIZE-1);
1601             hfp_connection->remote_call_services[hfp_connection->remote_call_services_index].name[HFP_CALL_SERVICE_SIZE - 1] = 0;
1602             hfp_next_remote_call_services_index(hfp_connection);
1603             break;
1604         case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
1605         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
1606             log_info("Parsed Generic status indicator: %s\n", hfp_connection->line_buffer);
1607             hfp_connection->generic_status_indicators[hfp_connection->parser_item_index].uuid = (uint16_t)btstack_atoi((char*)hfp_connection->line_buffer);
1608             hfp_next_indicators_index(hfp_connection);
1609             hfp_connection->generic_status_indicators_nr = hfp_connection->parser_item_index;
1610             break;
1611         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1612             // HF parses inital AG gen. ind. state
1613             log_info("Parsed List generic status indicator %s state: ", hfp_connection->line_buffer);
1614             hfp_connection->parser_item_index = hfp_parse_indicator_index(hfp_connection);
1615             break;
1616         case HFP_CMD_HF_INDICATOR_STATUS:
1617             hfp_connection->parser_indicator_index = hfp_parse_indicator_index(hfp_connection);
1618             log_info("Parsed HF indicator index %u", hfp_connection->parser_indicator_index);
1619             break;
1620         case HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE:
1621             // AG parses new gen. ind. state
1622             if (hfp_connection->ignore_value){
1623                 hfp_connection->ignore_value = 0;
1624                 log_info("Parsed Enable AG indicator pos %u('%s') - unchanged (stays %u)\n", hfp_connection->parser_item_index,
1625                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].name, hfp_connection->ag_indicators[hfp_connection->parser_item_index].enabled);
1626             }
1627             else if (hfp_connection->ag_indicators[hfp_connection->parser_item_index].mandatory){
1628                 log_info("Parsed Enable AG indicator pos %u('%s') - ignore (mandatory)\n",
1629                     hfp_connection->parser_item_index, hfp_connection->ag_indicators[hfp_connection->parser_item_index].name);
1630             } else {
1631                 value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1632                 hfp_connection->ag_indicators[hfp_connection->parser_item_index].enabled = value;
1633                 log_info("Parsed Enable AG indicator pos %u('%s'): %u\n", hfp_connection->parser_item_index,
1634                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].name, value);
1635             }
1636             hfp_next_indicators_index(hfp_connection);
1637             break;
1638         case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1639             // indicators are indexed starting with 1
1640             hfp_connection->parser_item_index = hfp_parse_indicator_index(hfp_connection);
1641             log_info("Parsed status of the AG indicator %d, status ", hfp_connection->parser_item_index);
1642             break;
1643         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1644             hfp_connection->network_operator.mode = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1645             log_info("Parsed network operator mode: %d, ", hfp_connection->network_operator.mode);
1646             break;
1647         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1648             if (hfp_connection->line_buffer[0] == '3'){
1649                 log_info("Parsed Set network operator format : %s, ", hfp_connection->line_buffer);
1650                 break;
1651             }
1652             // TODO emit ERROR, wrong format
1653             log_info("ERROR Set network operator format: index %s not supported\n", hfp_connection->line_buffer);
1654             break;
1655         case HFP_CMD_ERROR:
1656             break;
1657         case HFP_CMD_EXTENDED_AUDIO_GATEWAY_ERROR:
1658             hfp_connection->extended_audio_gateway_error = 1;
1659             hfp_connection->extended_audio_gateway_error_value = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1660             break;
1661         case HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR:
1662             hfp_connection->enable_extended_audio_gateway_error_report = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1663             hfp_connection->ok_pending = 1;
1664             hfp_connection->extended_audio_gateway_error = 0;
1665             break;
1666         case HFP_CMD_AG_SENT_PHONE_NUMBER:
1667         case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1668         case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1669             strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1670             hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1671             break;
1672         case HFP_CMD_CALL_HOLD:
1673             hfp_connection->ag_call_hold_action = hfp_connection->line_buffer[0] - '0';
1674             if (hfp_connection->line_buffer[1] != '\0'){
1675                 hfp_connection->call_index = btstack_atoi((char *)&hfp_connection->line_buffer[1]);
1676             }
1677             break;
1678         case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
1679             hfp_connection->ag_response_and_hold_action = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1680             break;
1681         case HFP_CMD_TRANSMIT_DTMF_CODES:
1682             hfp_connection->ag_dtmf_code = hfp_connection->line_buffer[0];
1683             break;
1684         case HFP_CMD_ENABLE_CLIP:
1685             hfp_connection->clip_enabled = hfp_connection->line_buffer[0] != '0';
1686             break;
1687         case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
1688             hfp_connection->call_waiting_notification_enabled = hfp_connection->line_buffer[0] != '0';
1689             break;
1690         case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
1691             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1692             hfp_connection->ag_activate_voice_recognition_value = value;
1693             break;
1694         case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
1695             switch(hfp_connection->parser_item_index){
1696                 case 0:
1697                     hfp_connection->ag_vra_status = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1698                     break;
1699                 case 1:
1700                     hfp_connection->ag_vra_state = (hfp_voice_recognition_state_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1701                     break;
1702                 case 2:
1703                     hfp_connection->ag_msg.text_id = 0;
1704                     for (i = 0 ; i < 4; i++){
1705                         hfp_connection->ag_msg.text_id = (hfp_connection->ag_msg.text_id << 4) | nibble_for_char(hfp_connection->line_buffer[i]);
1706                     }
1707                     break;
1708                 case 3:
1709                     hfp_connection->ag_msg.text_type = (hfp_text_type_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1710                     break;
1711                 case 4:
1712                     hfp_connection->ag_msg.text_operation = (hfp_text_operation_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1713                     break;
1714                 case 5:
1715                     hfp_connection->line_buffer[hfp_connection->line_size] = 0;
1716                     hfp_connection->ag_vra_msg_length = hfp_connection->line_size + 1;
1717                     break;
1718                 default:
1719                     break;
1720             }
1721             hfp_connection->parser_item_index++;
1722             break;
1723         default:
1724             break;
1725     }
1726 }
1727 
1728 static void hfp_handle_start_sdp_client_query(void * context){
1729     UNUSED(context);
1730 
1731     btstack_linked_list_iterator_t it;
1732     btstack_linked_list_iterator_init(&it, &hfp_connections);
1733     while (btstack_linked_list_iterator_has_next(&it)){
1734         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1735 
1736         if (connection->state != HFP_W2_SEND_SDP_QUERY) continue;
1737 
1738         connection->state = HFP_W4_SDP_QUERY_COMPLETE;
1739         hfp_sdp_query_context.local_role = connection->local_role;
1740         (void)memcpy(hfp_sdp_query_context.remote_address, connection->remote_addr, 6);
1741         sdp_client_query_rfcomm_channel_and_name_for_service_class_uuid(&handle_query_rfcomm_event, connection->remote_addr, connection->service_uuid);
1742         return;
1743     }
1744 }
1745 
1746 uint8_t hfp_establish_service_level_connection(bd_addr_t bd_addr, uint16_t service_uuid, hfp_role_t local_role){
1747     hfp_connection_t * connection = get_hfp_connection_context_for_bd_addr(bd_addr, local_role);
1748     if (connection){
1749         return ERROR_CODE_COMMAND_DISALLOWED;
1750     }
1751 
1752     connection = hfp_create_connection(bd_addr, local_role);
1753     if (!connection){
1754         return BTSTACK_MEMORY_ALLOC_FAILED;
1755     }
1756 
1757     connection->state = HFP_W2_SEND_SDP_QUERY;
1758 
1759     bd_addr_copy(connection->remote_addr, bd_addr);
1760     connection->service_uuid = service_uuid;
1761 
1762     hfp_sdp_query_request.callback = &hfp_handle_start_sdp_client_query;
1763     // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
1764     (void) sdp_client_register_query_callback(&hfp_sdp_query_request);
1765     return ERROR_CODE_SUCCESS;
1766 }
1767 
1768 void hfp_trigger_release_service_level_connection(hfp_connection_t * hfp_connection){
1769     // called internally, NULL check already performed
1770     btstack_assert(hfp_connection != NULL);
1771 
1772     hfp_trigger_release_audio_connection(hfp_connection);
1773     if (hfp_connection->state < HFP_W4_RFCOMM_CONNECTED){
1774         hfp_connection->state = HFP_IDLE;
1775         return;
1776     }
1777 
1778     if (hfp_connection->state == HFP_W4_RFCOMM_CONNECTED){
1779         hfp_connection->state = HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
1780         return;
1781     }
1782     hfp_connection->release_slc_connection = 1;
1783     if (hfp_connection->state < HFP_W4_SCO_CONNECTED){
1784         hfp_connection->state = HFP_W2_DISCONNECT_RFCOMM;
1785         return;
1786     }
1787 
1788     if (hfp_connection->state < HFP_W4_SCO_DISCONNECTED){
1789         hfp_connection->state = HFP_W2_DISCONNECT_SCO;
1790         hfp_connection->release_audio_connection = 1;
1791         return;
1792     }
1793 }
1794 
1795 uint8_t hfp_trigger_release_audio_connection(hfp_connection_t * hfp_connection){
1796     // called internally, NULL check already performed
1797     btstack_assert(hfp_connection != NULL);
1798     if (hfp_connection->state <= HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED){
1799         return ERROR_CODE_COMMAND_DISALLOWED;
1800     }
1801     switch (hfp_connection->state) {
1802         case HFP_W2_CONNECT_SCO:
1803             hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
1804             break;
1805         case HFP_W4_SCO_CONNECTED:
1806         case HFP_AUDIO_CONNECTION_ESTABLISHED:
1807             hfp_connection->release_audio_connection = 1;
1808             break;
1809         default:
1810             return ERROR_CODE_COMMAND_DISALLOWED;
1811     }
1812     return ERROR_CODE_SUCCESS;
1813 }
1814 
1815 static const struct link_settings {
1816     const uint16_t max_latency;
1817     const uint8_t  retransmission_effort;
1818     const uint16_t packet_types;
1819     const bool     eSCO;
1820     const uint8_t  codec;
1821 } hfp_link_settings [] = {
1822     { 0xffff, 0xff, SCO_PACKET_TYPES_HV1,  false, HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_D0
1823     { 0xffff, 0xff, SCO_PACKET_TYPES_HV3,  false, HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_D1
1824     { 0x0007, 0x01, SCO_PACKET_TYPES_EV3,  true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S1
1825     { 0x0007, 0x01, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S2
1826     { 0x000a, 0x01, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S3
1827     { 0x000c, 0x02, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S4
1828     { 0x0008, 0x02, SCO_PACKET_TYPES_EV3,  true,  HFP_CODEC_MSBC }, // HFP_LINK_SETTINGS_T1
1829     { 0x000d, 0x02, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_MSBC }  // HFP_LINK_SETTINGS_T2
1830 };
1831 
1832 void hfp_setup_synchronous_connection(hfp_connection_t * hfp_connection){
1833     // all packet types, fixed bandwidth
1834     int setting = hfp_connection->link_setting;
1835     log_info("hfp_setup_synchronous_connection using setting nr %u", setting);
1836     hfp_sco_establishment_active = hfp_connection;
1837     uint16_t sco_voice_setting = hci_get_sco_voice_setting();
1838     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1839 #ifdef ENABLE_BCM_PCM_WBS
1840         sco_voice_setting = 0x0063; // Transparent data, 16-bit for BCM controllers
1841 #else
1842         sco_voice_setting = 0x0043; // Transparent data, 8-bit otherwise
1843 #endif
1844     }
1845     // get packet types - bits 6-9 are 'don't allow'
1846     uint16_t packet_types = hfp_link_settings[setting].packet_types ^ 0x03c0;
1847     hci_send_cmd(&hci_setup_synchronous_connection, hfp_connection->acl_handle, 8000, 8000, hfp_link_settings[setting].max_latency,
1848         sco_voice_setting, hfp_link_settings[setting].retransmission_effort, packet_types);
1849 }
1850 
1851 void hfp_accept_synchronous_connection(hfp_connection_t * hfp_connection, bool incoming_eSCO){
1852 
1853     // remote supported feature eSCO is set if link type is eSCO
1854     // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
1855     uint16_t max_latency;
1856     uint8_t  retransmission_effort;
1857     uint16_t packet_types;
1858 
1859     if (incoming_eSCO && hci_extended_sco_link_supported() && hci_remote_esco_supported(hfp_connection->acl_handle)){
1860         max_latency = 0x000c;
1861         retransmission_effort = 0x02;
1862         // eSCO: EV3 and 2-EV3
1863         packet_types = 0x0048;
1864     } else {
1865         max_latency = 0xffff;
1866         retransmission_effort = 0xff;
1867         // sco: HV1 and HV3
1868         packet_types = 0x005;
1869     }
1870 
1871     // mSBC only allows for transparent data
1872     uint16_t sco_voice_setting = hci_get_sco_voice_setting();
1873     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1874 #ifdef ENABLE_BCM_PCM_WBS
1875         sco_voice_setting = 0x0063; // Transparent data, 16-bit for BCM controllers
1876 #else
1877         sco_voice_setting = 0x0043; // Transparent data, 8-bit otherwise
1878 #endif
1879     }
1880 
1881     // filter packet types
1882     packet_types &= hfp_get_sco_packet_types();
1883 
1884     // bits 6-9 are 'don't allow'
1885     packet_types ^= 0x3c0;
1886 
1887     log_info("HFP: sending hci_accept_connection_request, packet types 0x%04x, sco_voice_setting 0x%02x", packet_types, sco_voice_setting);
1888     hci_send_cmd(&hci_accept_synchronous_connection, hfp_connection->remote_addr, 8000, 8000, max_latency,
1889                  sco_voice_setting, retransmission_effort, packet_types);
1890 }
1891 
1892 #ifdef ENABLE_CC256X_ASSISTED_HFP
1893 void hfp_cc256x_prepare_for_sco(hfp_connection_t * hfp_connection){
1894     hfp_connection->cc256x_send_write_codec_config = true;
1895     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1896         hfp_connection->cc256x_send_wbs_associate = true;
1897     }
1898 }
1899 
1900 void hfp_cc256x_write_codec_config(hfp_connection_t * hfp_connection){
1901     uint32_t sample_rate_hz;
1902     uint16_t clock_rate_khz;
1903     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1904         clock_rate_khz = 512;
1905         sample_rate_hz = 16000;
1906     } else {
1907         clock_rate_khz = 256;
1908         sample_rate_hz = 8000;
1909     }
1910     uint8_t clock_direction = 0;        // master
1911     uint16_t frame_sync_duty_cycle = 0; // i2s with 50%
1912     uint8_t  frame_sync_edge = 1;       // rising edge
1913     uint8_t  frame_sync_polarity = 0;   // active high
1914     uint8_t  reserved = 0;
1915     uint16_t size = 16;
1916     uint16_t chan_1_offset = 1;
1917     uint16_t chan_2_offset = chan_1_offset + size;
1918     uint8_t  out_edge = 1;              // rising
1919     uint8_t  in_edge = 0;               // falling
1920     hci_send_cmd(&hci_ti_write_codec_config, clock_rate_khz, clock_direction, sample_rate_hz, frame_sync_duty_cycle,
1921                  frame_sync_edge, frame_sync_polarity, reserved,
1922                  size, chan_1_offset, out_edge, size, chan_1_offset, in_edge, reserved,
1923                  size, chan_2_offset, out_edge, size, chan_2_offset, in_edge, reserved);
1924 }
1925 #endif
1926 
1927 #ifdef ENABLE_BCM_PCM_WBS
1928 void hfp_bcm_prepare_for_sco(hfp_connection_t * hfp_connection){
1929     hfp_connection->bcm_send_write_i2spcm_interface_param = true;
1930     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1931         hfp_connection->bcm_send_enable_wbs = true;
1932     }
1933 }
1934 void hfp_bcm_write_i2spcm_interface_param(hfp_connection_t * hfp_connection){
1935     uint8_t sample_rate = (hfp_connection->negotiated_codec == HFP_CODEC_MSBC) ? 1 : 0;
1936     // i2s enable, master, 8/16 kHz, 512 kHz
1937     hci_send_cmd(&hci_bcm_write_i2spcm_interface_paramhci_bcm_write_i2spcm_interface_param, 1, 1, sample_rate, 2);
1938 }
1939 #endif
1940 
1941 void hfp_set_hf_callback(btstack_packet_handler_t callback){
1942     hfp_hf_callback = callback;
1943 }
1944 
1945 void hfp_set_ag_callback(btstack_packet_handler_t callback){
1946     hfp_ag_callback = callback;
1947 }
1948 
1949 void hfp_set_ag_rfcomm_packet_handler(btstack_packet_handler_t handler){
1950     hfp_ag_rfcomm_packet_handler = handler;
1951 }
1952 
1953 void hfp_set_hf_rfcomm_packet_handler(btstack_packet_handler_t handler){
1954     hfp_hf_rfcomm_packet_handler = handler;
1955 }
1956 
1957 void hfp_init(void){
1958     hfp_allowed_sco_packet_types = SCO_PACKET_TYPES_ALL;
1959 }
1960 
1961 void hfp_deinit(void){
1962     hfp_allowed_sco_packet_types = 0;
1963     hfp_connections = NULL;
1964     hfp_hf_callback = NULL;
1965     hfp_ag_callback = NULL;
1966     hfp_hf_rfcomm_packet_handler = NULL;
1967     hfp_ag_rfcomm_packet_handler = NULL;
1968     hfp_sco_establishment_active = NULL;
1969     (void) memset(&hfp_sdp_query_context, 0, sizeof(hfp_sdp_query_context_t));
1970     (void) memset(&hfp_sdp_query_request, 0, sizeof(btstack_context_callback_registration_t));
1971 }
1972 
1973 void hfp_set_sco_packet_types(uint16_t packet_types){
1974     hfp_allowed_sco_packet_types = packet_types;
1975 }
1976 
1977 uint16_t hfp_get_sco_packet_types(void){
1978     return hfp_allowed_sco_packet_types;
1979 }
1980 
1981 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){
1982     int8_t setting = (int8_t) current_setting;
1983     bool can_use_eSCO = local_eSCO_supported && remote_eSCO_supported;
1984     while (setting > 0){
1985         setting--;
1986         // skip if eSCO required but not available
1987         if (hfp_link_settings[setting].eSCO && !can_use_eSCO) continue;
1988         // skip if S4 but not supported
1989         if ((setting == (int8_t) HFP_LINK_SETTINGS_S4) && !eSCO_S4_supported) continue;
1990         // skip wrong codec
1991         if ( hfp_link_settings[setting].codec != negotiated_codec) continue;
1992         // skip disabled packet types
1993         uint16_t required_packet_types = hfp_link_settings[setting].packet_types;
1994         uint16_t allowed_packet_types  = hfp_allowed_sco_packet_types;
1995         if ((required_packet_types & allowed_packet_types) == 0) continue;
1996 
1997         // found matching setting
1998         return (hfp_link_settings_t) setting;
1999     }
2000     return HFP_LINK_SETTINGS_NONE;
2001 }
2002 
2003 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){
2004     bool local_eSCO_supported  = hci_extended_sco_link_supported();
2005     bool remote_eSCO_supported = hci_remote_esco_supported(hfp_connection->acl_handle);
2006     uint8_t negotiated_codec   = hfp_connection->negotiated_codec;
2007     return  hfp_next_link_setting(current_setting, local_eSCO_supported, remote_eSCO_supported, eSCO_S4_supported, negotiated_codec);
2008 }
2009 
2010 void hfp_init_link_settings(hfp_connection_t * hfp_connection, uint8_t eSCO_S4_supported){
2011     // get highest possible link setting
2012     hfp_connection->link_setting = hfp_next_link_setting_for_connection(HFP_LINK_SETTINGS_NONE, hfp_connection, eSCO_S4_supported);
2013     log_info("hfp_init_link_settings: %u", hfp_connection->link_setting);
2014 }
2015 
2016 #define HFP_HF_RX_DEBUG_PRINT_LINE 80
2017 
2018 void hfp_log_rfcomm_message(const char * tag, uint8_t * packet, uint16_t size){
2019 #ifdef ENABLE_LOG_INFO
2020     // encode \n\r
2021     char printable[HFP_HF_RX_DEBUG_PRINT_LINE+2];
2022     int i = 0;
2023     int pos;
2024     for (pos=0 ; (pos < size) && (i < (HFP_HF_RX_DEBUG_PRINT_LINE - 3)) ; pos++){
2025         switch (packet[pos]){
2026             case '\n':
2027                 printable[i++] = '\\';
2028                 printable[i++] = 'n';
2029                 break;
2030             case '\r':
2031                 printable[i++] = '\\';
2032                 printable[i++] = 'r';
2033                 break;
2034             default:
2035                 printable[i++] = packet[pos];
2036                 break;
2037         }
2038     }
2039     printable[i] = 0;
2040     log_info("%s: '%s'", tag, printable);
2041 #endif
2042 }
2043