xref: /btstack/src/classic/hfp.c (revision b28dc8004dd8d4fb9020a6dcd2bc81f05d36a008)
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     hfp_connection->command = HFP_CMD_NONE;
592 
593     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
594     hfp_connection->sco_handle = HCI_CON_HANDLE_INVALID;
595 
596     hfp_reset_context_flags(hfp_connection);
597 
598     btstack_linked_list_add(&hfp_connections, (btstack_linked_item_t*)hfp_connection);
599     return hfp_connection;
600 }
601 
602 void hfp_finalize_connection_context(hfp_connection_t * hfp_connection){
603     btstack_linked_list_remove(&hfp_connections, (btstack_linked_item_t*) hfp_connection);
604     btstack_memory_hfp_connection_free(hfp_connection);
605 }
606 
607 static hfp_connection_t * hfp_create_connection(bd_addr_t bd_addr, hfp_role_t local_role){
608     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_bd_addr(bd_addr, local_role);
609     if (hfp_connection) return  hfp_connection;
610     hfp_connection = create_hfp_connection_context();
611     (void)memcpy(hfp_connection->remote_addr, bd_addr, 6);
612     hfp_connection->local_role = local_role;
613     log_info("Create HFP context %p: role %u, addr %s", hfp_connection, local_role, bd_addr_to_str(bd_addr));
614 
615     return hfp_connection;
616 }
617 
618 /* @param network.
619  * 0 == no ability to reject a call.
620  * 1 == ability to reject a call.
621  */
622 
623 /* @param suported_features
624  * HF bit 0: EC and/or NR function (yes/no, 1 = yes, 0 = no)
625  * HF bit 1: Call waiting or three-way calling(yes/no, 1 = yes, 0 = no)
626  * HF bit 2: CLI presentation capability (yes/no, 1 = yes, 0 = no)
627  * HF bit 3: Voice recognition activation (yes/no, 1= yes, 0 = no)
628  * HF bit 4: Remote volume control (yes/no, 1 = yes, 0 = no)
629  * HF bit 5: Wide band speech (yes/no, 1 = yes, 0 = no)
630  */
631  /* Bit position:
632  * AG bit 0: Three-way calling (yes/no, 1 = yes, 0 = no)
633  * AG bit 1: EC and/or NR function (yes/no, 1 = yes, 0 = no)
634  * AG bit 2: Voice recognition function (yes/no, 1 = yes, 0 = no)
635  * AG bit 3: In-band ring tone capability (yes/no, 1 = yes, 0 = no)
636  * AG bit 4: Attach a phone number to a voice tag (yes/no, 1 = yes, 0 = no)
637  * AG bit 5: Wide band speech (yes/no, 1 = yes, 0 = no)
638  */
639 
640 void hfp_create_sdp_record(uint8_t * service, uint32_t service_record_handle, uint16_t service_uuid, int rfcomm_channel_nr, const char * name){
641     uint8_t* attribute;
642     de_create_sequence(service);
643 
644     // 0x0000 "Service Record Handle"
645     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
646     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
647 
648     // 0x0001 "Service Class ID List"
649     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
650     attribute = de_push_sequence(service);
651     {
652         //  "UUID for Service"
653         de_add_number(attribute, DE_UUID, DE_SIZE_16, service_uuid);
654         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_GENERIC_AUDIO);
655     }
656     de_pop_sequence(service, attribute);
657 
658     // 0x0004 "Protocol Descriptor List"
659     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
660     attribute = de_push_sequence(service);
661     {
662         uint8_t* l2cpProtocol = de_push_sequence(attribute);
663         {
664             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
665         }
666         de_pop_sequence(attribute, l2cpProtocol);
667 
668         uint8_t* rfcomm = de_push_sequence(attribute);
669         {
670             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_RFCOMM);  // rfcomm_service
671             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
672         }
673         de_pop_sequence(attribute, rfcomm);
674     }
675     de_pop_sequence(service, attribute);
676 
677 
678     // 0x0005 "Public Browse Group"
679     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
680     attribute = de_push_sequence(service);
681     {
682         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
683     }
684     de_pop_sequence(service, attribute);
685 
686     // 0x0009 "Bluetooth Profile Descriptor List"
687     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
688     attribute = de_push_sequence(service);
689     {
690         uint8_t *sppProfile = de_push_sequence(attribute);
691         {
692             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_HANDSFREE);
693             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0108); // Verision 1.8
694         }
695         de_pop_sequence(attribute, sppProfile);
696     }
697     de_pop_sequence(service, attribute);
698 
699     // 0x0100 "Service Name"
700     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
701     de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
702 }
703 
704 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
705     UNUSED(packet_type);    // ok: handling own sdp events
706     UNUSED(channel);        // ok: no channel
707     UNUSED(size);           // ok: handling own sdp events
708 
709     hfp_connection_t * hfp_connection = get_hfp_connection_context_for_bd_addr(hfp_sdp_query_context.remote_address, hfp_sdp_query_context.local_role);
710     if (hfp_connection == NULL) {
711         log_info("connection with %s and local role %d not found", hfp_sdp_query_context.remote_address, hfp_sdp_query_context.local_role);
712         return;
713     }
714 
715     switch (hci_event_packet_get_type(packet)){
716         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
717             hfp_connection->rfcomm_channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
718             break;
719         case SDP_EVENT_QUERY_COMPLETE:
720             if (hfp_connection->rfcomm_channel_nr > 0){
721                 hfp_connection->state = HFP_W4_RFCOMM_CONNECTED;
722                 btstack_packet_handler_t packet_handler;
723                 switch (hfp_connection->local_role){
724                     case HFP_ROLE_AG:
725                         packet_handler = hfp_ag_rfcomm_packet_handler;
726                         break;
727                     case HFP_ROLE_HF:
728                         packet_handler = hfp_hf_rfcomm_packet_handler;
729                         break;
730                     default:
731                         btstack_assert(false);
732                         return;
733                 }
734 
735                 rfcomm_create_channel(packet_handler, hfp_connection->remote_addr, hfp_connection->rfcomm_channel_nr, NULL);
736 
737             } else {
738                 hfp_connection->state = HFP_IDLE;
739                 uint8_t status = sdp_event_query_complete_get_status(packet);
740                 if (status == ERROR_CODE_SUCCESS){
741                     // report service not found
742                     status = SDP_SERVICE_NOT_FOUND;
743                 }
744                 hfp_emit_slc_connection_event(hfp_connection, status, HCI_CON_HANDLE_INVALID, hfp_connection->remote_addr);
745                 log_info("rfcomm service not found, status 0x%02x", status);
746             }
747 
748             // register the SDP Query request to check if there is another connection waiting for the query
749             // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
750             (void) sdp_client_register_query_callback(&hfp_sdp_query_request);
751             break;
752         default:
753             break;
754     }
755 }
756 
757 // returns 0 if unexpected error or no other link options remained, otherwise 1
758 static int hfp_handle_failed_sco_connection(uint8_t status){
759 
760     if (!hfp_sco_establishment_active){
761         log_info("(e)SCO Connection failed but not started by us");
762         return 0;
763     }
764 
765     log_info("(e)SCO Connection failed 0x%02x", status);
766     switch (status){
767         case ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE:
768         case ERROR_CODE_UNSPECIFIED_ERROR:
769         case ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES:
770             break;
771         default:
772             return 0;
773     }
774 
775     // note: eSCO_S4 supported flag not available, but it's only relevant for highest CVSD link setting (and the current failed)
776     hfp_link_settings_t next_setting = hfp_next_link_setting_for_connection(hfp_sco_establishment_active->link_setting, hfp_sco_establishment_active, false);
777 
778     // handle no valid setting found
779     if (next_setting == HFP_LINK_SETTINGS_NONE) {
780         if (hfp_sco_establishment_active->negotiated_codec == HFP_CODEC_MSBC){
781             log_info("T2/T1 failed, fallback to CVSD - D1");
782             hfp_sco_establishment_active->negotiated_codec = HFP_CODEC_CVSD;
783             hfp_sco_establishment_active->sco_for_msbc_failed = 1;
784             hfp_sco_establishment_active->ag_send_common_codec = true;
785             hfp_sco_establishment_active->link_setting = HFP_LINK_SETTINGS_D1;
786         } else {
787             // no other options
788             return 0;
789         }
790     }
791 
792     log_info("e)SCO Connection: try new link_setting %d", next_setting);
793     hfp_sco_establishment_active->establish_audio_connection = 1;
794     hfp_sco_establishment_active->link_setting = next_setting;
795     hfp_sco_establishment_active = NULL;
796     return 1;
797 }
798 
799 void hfp_handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, hfp_role_t local_role){
800     UNUSED(packet_type);
801     UNUSED(channel);    // ok: no channel
802     UNUSED(size);
803 
804     bd_addr_t event_addr;
805     hci_con_handle_t handle;
806     hfp_connection_t * hfp_connection = NULL;
807     uint8_t status;
808 
809     log_debug("HFP HCI event handler type %u, event type %x, size %u", packet_type, hci_event_packet_get_type(packet), size);
810 
811     switch (hci_event_packet_get_type(packet)) {
812 
813         case HCI_EVENT_CONNECTION_REQUEST:
814             switch(hci_event_connection_request_get_link_type(packet)){
815                 case 0: //  SCO
816                 case 2: // eSCO
817                     hci_event_connection_request_get_bd_addr(packet, event_addr);
818                     hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
819                     if (!hfp_connection) break;
820                     if (hci_event_connection_request_get_link_type(packet) == 2){
821                         hfp_connection->accept_sco = 2;
822                     } else {
823                         hfp_connection->accept_sco = 1;
824                     }
825 #ifdef ENABLE_CC256X_ASSISTED_HFP
826                     hfp_cc256x_prepare_for_sco(hfp_connection);
827 #endif
828 #ifdef ENABLE_BCM_PCM_WBS
829                     hfp_bcm_prepare_for_sco(hfp_connection);
830 #endif
831                     log_info("accept sco %u\n", hfp_connection->accept_sco);
832                     hfp_sco_establishment_active = hfp_connection;
833                     break;
834                 default:
835                     break;
836             }
837             break;
838 
839         case HCI_EVENT_COMMAND_STATUS:
840             if (hci_event_command_status_get_command_opcode(packet) == hci_setup_synchronous_connection.opcode) {
841                 if (hfp_sco_establishment_active == NULL) break;
842                 status = hci_event_command_status_get_status(packet);
843                 if (status == ERROR_CODE_SUCCESS) break;
844 
845                 hfp_connection = hfp_sco_establishment_active;
846                 if (hfp_handle_failed_sco_connection(status)) break;
847                 hfp_connection->establish_audio_connection = 0;
848                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
849                 hfp_emit_sco_event(hfp_connection, status, 0, hfp_connection->remote_addr, hfp_connection->negotiated_codec);
850             }
851             break;
852 
853         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
854             if (hfp_sco_establishment_active == NULL) break;
855             hci_event_synchronous_connection_complete_get_bd_addr(packet, event_addr);
856             hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
857             if (!hfp_connection) {
858                 log_error("HFP: connection does not exist for remote with addr %s.", bd_addr_to_str(event_addr));
859                 return;
860             }
861 
862             status = hci_event_synchronous_connection_complete_get_status(packet);
863             if (status != ERROR_CODE_SUCCESS){
864                 hfp_connection->accept_sco = 0;
865                 if (hfp_handle_failed_sco_connection(status)) break;
866 
867                 hfp_connection->establish_audio_connection = 0;
868                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
869                 hfp_emit_sco_event(hfp_connection, status, 0, event_addr, hfp_connection->negotiated_codec);
870                 break;
871             }
872 
873             uint16_t sco_handle = hci_event_synchronous_connection_complete_get_handle(packet);
874             uint8_t  link_type = hci_event_synchronous_connection_complete_get_link_type(packet);
875             uint8_t  transmission_interval = hci_event_synchronous_connection_complete_get_transmission_interval(packet);  // measured in slots
876             uint8_t  retransmission_interval = hci_event_synchronous_connection_complete_get_retransmission_interval(packet);// measured in slots
877             uint16_t rx_packet_length = hci_event_synchronous_connection_complete_get_rx_packet_length(packet); // measured in bytes
878             uint16_t tx_packet_length = hci_event_synchronous_connection_complete_get_tx_packet_length(packet); // measured in bytes
879 
880             switch (link_type){
881                 case 0x00:
882                     log_info("SCO Connection established.");
883                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
884                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
885                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
886                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
887                     break;
888                 case 0x02:
889                     log_info("eSCO Connection established. \n");
890                     break;
891                 default:
892                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
893                     break;
894             }
895 
896             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
897                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)\n", sco_handle,
898                  bd_addr_to_str(event_addr), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length,
899                  hci_event_synchronous_connection_complete_get_air_mode(packet));
900 
901             if (hfp_connection->state == HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
902                 log_info("SCO about to disconnect: HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN");
903                 hfp_connection->state = HFP_W2_DISCONNECT_SCO;
904                 break;
905             }
906             hfp_connection->sco_handle = sco_handle;
907             hfp_connection->establish_audio_connection = 0;
908 
909             hfp_connection->state = HFP_AUDIO_CONNECTION_ESTABLISHED;
910 
911             switch (hfp_connection->vra_state){
912                 case HFP_VRA_VOICE_RECOGNITION_ACTIVATED:
913                     hfp_connection->ag_audio_connection_opened_before_vra = false;
914                     break;
915                 default:
916                     hfp_connection->ag_audio_connection_opened_before_vra = true;
917                     break;
918             }
919             hfp_emit_sco_event(hfp_connection, status, sco_handle, event_addr, hfp_connection->negotiated_codec);
920             break;
921         }
922 
923         case HCI_EVENT_DISCONNECTION_COMPLETE:
924             handle = little_endian_read_16(packet,3);
925             hfp_connection = get_hfp_connection_context_for_sco_handle(handle, local_role);
926 
927             if (!hfp_connection) break;
928 
929 #ifdef ENABLE_CC256X_ASSISTED_HFP
930             hfp_connection->cc256x_send_wbs_disassociate = true;
931 #endif
932 #ifdef ENABLE_BCM_PCM_WBS
933             hfp_connection->bcm_send_disable_wbs = true;
934 #endif
935             if (hfp_connection->sco_handle == handle){
936                 hfp_connection->sco_handle = HCI_CON_HANDLE_INVALID;
937                 hfp_connection->release_audio_connection = 0;
938                 hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
939                 hfp_emit_audio_connection_released(hfp_connection, handle);
940 
941                 hfp_connection->ag_audio_connection_opened_before_vra = false;
942 
943                 if (hfp_connection->acl_handle == HCI_CON_HANDLE_INVALID){
944                     hfp_reset_voice_recognition(hfp_connection);
945                     hfp_emit_event(hfp_connection, HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_RELEASED, 0);
946                     hfp_finalize_connection_context(hfp_connection);
947                 } else if (hfp_connection->release_slc_connection == 1){
948                     hfp_connection->release_slc_connection = 0;
949                     hfp_connection->state = HFP_W2_DISCONNECT_RFCOMM;
950                     rfcomm_disconnect(hfp_connection->acl_handle);
951                 }
952             }
953 
954             if (hfp_connection->state == HFP_W4_SCO_DISCONNECTED_TO_SHUTDOWN){
955                 // RFCOMM already closed -> remote power off
956 #if defined(ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
957                 hfp_connection->state = HFP_W4_WBS_SHUTDOWN;
958 #else
959                 hfp_finalize_connection_context(hfp_connection);
960 #endif
961                 break;
962             }
963             break;
964 
965         default:
966             break;
967     }
968 }
969 
970 
971 void hfp_handle_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, hfp_role_t local_role){
972     UNUSED(packet_type);
973     UNUSED(channel);    // ok: no channel
974     UNUSED(size);
975 
976     bd_addr_t event_addr;
977     uint16_t rfcomm_cid;
978     hfp_connection_t * hfp_connection = NULL;
979     uint8_t status;
980 
981     log_debug("HFP packet_handler type %u, event type %x, size %u", packet_type, hci_event_packet_get_type(packet), size);
982 
983     switch (hci_event_packet_get_type(packet)) {
984 
985         case RFCOMM_EVENT_INCOMING_CONNECTION:
986             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
987             rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr);
988             hfp_connection = hfp_create_connection(event_addr, local_role);
989             if (!hfp_connection){
990                 log_info("hfp: no memory to accept incoming connection - decline");
991                 rfcomm_decline_connection(rfcomm_event_incoming_connection_get_rfcomm_cid(packet));
992                 return;
993             }
994             if (hfp_connection->state != HFP_IDLE) {
995                 log_error("hfp: incoming connection but not idle, reject");
996                 rfcomm_decline_connection(rfcomm_event_incoming_connection_get_rfcomm_cid(packet));
997                 return;
998             }
999 
1000             hfp_connection->rfcomm_cid = rfcomm_event_incoming_connection_get_rfcomm_cid(packet);
1001             hfp_connection->state = HFP_W4_RFCOMM_CONNECTED;
1002             rfcomm_accept_connection(hfp_connection->rfcomm_cid);
1003             break;
1004 
1005         case RFCOMM_EVENT_CHANNEL_OPENED:
1006             rfcomm_event_channel_opened_get_bd_addr(packet, event_addr);
1007 
1008             hfp_connection = get_hfp_connection_context_for_bd_addr(event_addr, local_role);
1009             btstack_assert(hfp_connection != NULL);
1010 
1011             if (hfp_connection->state != HFP_W4_RFCOMM_CONNECTED){
1012                 break;
1013             }
1014 
1015             status = rfcomm_event_channel_opened_get_status(packet);
1016             if (status != ERROR_CODE_SUCCESS) {
1017                 hfp_emit_slc_connection_event(hfp_connection, status, rfcomm_event_channel_opened_get_con_handle(packet), event_addr);
1018                 hfp_finalize_connection_context(hfp_connection);
1019                 break;
1020             }
1021 
1022             hfp_connection->acl_handle = rfcomm_event_channel_opened_get_con_handle(packet);
1023             hfp_connection->rfcomm_cid = rfcomm_event_channel_opened_get_rfcomm_cid(packet);
1024             hfp_connection->rfcomm_mtu = rfcomm_event_channel_opened_get_max_frame_size(packet);
1025             bd_addr_copy(hfp_connection->remote_addr, event_addr);
1026             hfp_connection->state = HFP_EXCHANGE_SUPPORTED_FEATURES;
1027 
1028             rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1029             break;
1030 
1031         case RFCOMM_EVENT_CHANNEL_CLOSED:
1032             rfcomm_cid = little_endian_read_16(packet,2);
1033             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
1034             if (!hfp_connection) break;
1035             switch (hfp_connection->state){
1036                 case HFP_W4_RFCOMM_DISCONNECTED_AND_RESTART:
1037                     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
1038                     hfp_connection->state = HFP_IDLE;
1039                     hfp_establish_service_level_connection(hfp_connection->remote_addr, hfp_connection->service_uuid, local_role);
1040                     break;
1041 
1042                 case HFP_AUDIO_CONNECTION_ESTABLISHED:
1043                     // service connection was released, this implicitly releases audio connection as well
1044                     hfp_connection->release_audio_connection = 0;
1045                     hfp_connection->acl_handle = HCI_CON_HANDLE_INVALID;
1046                     hfp_connection->state = HFP_W4_SCO_DISCONNECTED_TO_SHUTDOWN;
1047                     gap_disconnect(hfp_connection->sco_handle);
1048                     break;
1049 
1050                 default:
1051                     // regular case
1052                     hfp_reset_voice_recognition(hfp_connection);
1053                     hfp_emit_event(hfp_connection, HFP_SUBEVENT_SERVICE_LEVEL_CONNECTION_RELEASED, 0);
1054                     hfp_finalize_connection_context(hfp_connection);
1055                     break;
1056             }
1057             break;
1058 
1059         default:
1060             break;
1061     }
1062 }
1063 // translates command string into hfp_command_t CMD
1064 
1065 typedef struct {
1066     const char * command;
1067     hfp_command_t command_id;
1068 } hfp_command_entry_t;
1069 
1070 static hfp_command_entry_t hfp_ag_commmand_table[] = {
1071     { "AT+BAC=",   HFP_CMD_AVAILABLE_CODECS },
1072     { "AT+BCC",    HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP },
1073     { "AT+BCS=",   HFP_CMD_HF_CONFIRMED_CODEC },
1074     { "AT+BIA=",   HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE, }, // +BIA:<enabled>,,<enabled>,,,<enabled>
1075     { "AT+BIEV=",  HFP_CMD_HF_INDICATOR_STATUS },
1076     { "AT+BIND=",  HFP_CMD_LIST_GENERIC_STATUS_INDICATORS },
1077     { "AT+BIND=?", HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS },
1078     { "AT+BIND?",  HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE },
1079     { "AT+BINP=",  HFP_CMD_HF_REQUEST_PHONE_NUMBER },
1080     { "AT+BLDN",   HFP_CMD_REDIAL_LAST_NUMBER },
1081     { "AT+BRSF=",  HFP_CMD_SUPPORTED_FEATURES },
1082     { "AT+BTRH=",  HFP_CMD_RESPONSE_AND_HOLD_COMMAND },
1083     { "AT+BTRH?",  HFP_CMD_RESPONSE_AND_HOLD_QUERY },
1084     { "AT+BVRA=",  HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION },
1085     { "AT+CCWA=",  HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION},
1086     { "AT+CHLD=",  HFP_CMD_CALL_HOLD },
1087     { "AT+CHLD=?", HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES },
1088     { "AT+CHUP",   HFP_CMD_HANG_UP_CALL },
1089     { "AT+CIND=?", HFP_CMD_RETRIEVE_AG_INDICATORS },
1090     { "AT+CIND?",  HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS },
1091     { "AT+CLCC",   HFP_CMD_LIST_CURRENT_CALLS },
1092     { "AT+CLIP=",  HFP_CMD_ENABLE_CLIP},
1093     { "AT+CMEE=",  HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR},
1094     { "AT+CMER=",  HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE },
1095     { "AT+CNUM",   HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION },
1096     { "AT+COPS=",  HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT },
1097     { "AT+COPS?",  HFP_CMD_QUERY_OPERATOR_SELECTION_NAME },
1098     { "AT+NREC=",  HFP_CMD_TURN_OFF_EC_AND_NR, },
1099     { "AT+VGM=",   HFP_CMD_SET_MICROPHONE_GAIN },
1100     { "AT+VGS=",   HFP_CMD_SET_SPEAKER_GAIN },
1101     { "AT+VTS=",   HFP_CMD_TRANSMIT_DTMF_CODES },
1102     { "ATA",       HFP_CMD_CALL_ANSWERED },
1103 };
1104 
1105 static hfp_command_entry_t hfp_hf_commmand_table[] = {
1106     { "+BCS:",  HFP_CMD_AG_SUGGESTED_CODEC },
1107     { "+BIND:", HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS },
1108     { "+BINP",  HFP_CMD_AG_SENT_PHONE_NUMBER },
1109     { "+BRSF:", HFP_CMD_SUPPORTED_FEATURES },
1110     { "+BSIR:", HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING },
1111     { "+BTRH:", HFP_CMD_RESPONSE_AND_HOLD_STATUS },
1112     { "+BVRA:", HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION },
1113     { "+CCWA:", HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE, },
1114     { "+CHLD:", HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES },
1115     { "+CIEV:", HFP_CMD_TRANSFER_AG_INDICATOR_STATUS},
1116     { "+CIND:", HFP_CMD_RETRIEVE_AG_INDICATORS_GENERIC },
1117     { "+CLCC:", HFP_CMD_LIST_CURRENT_CALLS },
1118     { "+CLIP:", HFP_CMD_AG_SENT_CLIP_INFORMATION },
1119     { "+CME ERROR:", HFP_CMD_EXTENDED_AUDIO_GATEWAY_ERROR },
1120     { "+CNUM:", HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION},
1121     { "+COPS:", HFP_CMD_QUERY_OPERATOR_SELECTION_NAME },
1122     { "+VGM:",  HFP_CMD_SET_MICROPHONE_GAIN },
1123     { "+VGM=",  HFP_CMD_SET_MICROPHONE_GAIN },
1124     { "+VGS:",  HFP_CMD_SET_SPEAKER_GAIN},
1125     { "+VGS=",  HFP_CMD_SET_SPEAKER_GAIN},
1126     { "ERROR",  HFP_CMD_ERROR},
1127     { "NOP",    HFP_CMD_NONE}, // dummy command used by unit tests
1128     { "OK",     HFP_CMD_OK },
1129     { "RING",   HFP_CMD_RING },
1130 };
1131 
1132 static hfp_command_t parse_command(const char * line_buffer, int isHandsFree){
1133 
1134     // table lookup based on role
1135     uint16_t num_entries;
1136     hfp_command_entry_t * table;
1137     if (isHandsFree == 0){
1138         table = hfp_ag_commmand_table;
1139         num_entries = sizeof(hfp_ag_commmand_table) / sizeof(hfp_command_entry_t);
1140     } else {
1141         table = hfp_hf_commmand_table;
1142         num_entries = sizeof(hfp_hf_commmand_table) / sizeof(hfp_command_entry_t);
1143     }
1144     // binary search
1145     uint16_t left = 0;
1146     uint16_t right = num_entries - 1;
1147     while (left <= right){
1148         uint16_t middle = left + (right - left) / 2;
1149         hfp_command_entry_t *entry = &table[middle];
1150         int match = strcmp(line_buffer, entry->command);
1151         if (match < 0){
1152             // search term is lower than middle element
1153             if (right == 0) break;
1154             right = middle - 1;
1155         } else if (match == 0){
1156             return entry->command_id;
1157         } else {
1158             // search term is higher than middle element
1159             left = middle + 1;
1160         }
1161     }
1162 
1163     // note: if parser in CMD_HEADER state would treats digits and maybe '+' as separator, match on "ATD" would work.
1164     // note: phone number is currently expected in line_buffer[3..]
1165     // prefix match on 'ATD', AG only
1166     if ((isHandsFree == 0) && (strncmp(line_buffer, HFP_CALL_PHONE_NUMBER, strlen(HFP_CALL_PHONE_NUMBER)) == 0)){
1167         return HFP_CMD_CALL_PHONE_NUMBER;
1168     }
1169 
1170     // Valid looking, but unknown commands/responses
1171     if ((isHandsFree == 0) && (strncmp(line_buffer, "AT+", 3) == 0)){
1172         return HFP_CMD_UNKNOWN;
1173     }
1174 
1175     if ((isHandsFree != 0) && (strncmp(line_buffer, "+", 1) == 0)){
1176         return HFP_CMD_UNKNOWN;
1177     }
1178 
1179     return HFP_CMD_NONE;
1180 }
1181 
1182 static void hfp_parser_store_byte(hfp_connection_t * hfp_connection, uint8_t byte){
1183     if ((hfp_connection->line_size + 1) >= HFP_MAX_VR_TEXT_SIZE) return;
1184     hfp_connection->line_buffer[hfp_connection->line_size++] = byte;
1185     hfp_connection->line_buffer[hfp_connection->line_size] = 0;
1186 }
1187 static int hfp_parser_is_buffer_empty(hfp_connection_t * hfp_connection){
1188     return hfp_connection->line_size == 0;
1189 }
1190 
1191 static int hfp_parser_is_end_of_line(uint8_t byte){
1192     return (byte == '\n') || (byte == '\r');
1193 }
1194 
1195 static void hfp_parser_reset_line_buffer(hfp_connection_t *hfp_connection) {
1196     hfp_connection->line_size = 0;
1197     // hfp_connection->line_buffer[0] = 0;
1198 }
1199 
1200 static void hfp_parser_store_if_token(hfp_connection_t * hfp_connection, uint8_t byte){
1201     switch (byte){
1202         case ',':
1203 		case '-':
1204         case ';':
1205         case '(':
1206         case ')':
1207         case '\n':
1208         case '\r':
1209             break;
1210         default:
1211             hfp_parser_store_byte(hfp_connection, byte);
1212             break;
1213     }
1214 }
1215 
1216 static bool hfp_parser_is_separator( uint8_t byte){
1217     switch (byte){
1218         case ',':
1219 		case '-':
1220         case ';':
1221         case '\n':
1222         case '\r':
1223             return true;
1224         default:
1225             return false;
1226     }
1227 }
1228 
1229 static bool hfp_parse_byte(hfp_connection_t * hfp_connection, uint8_t byte, int isHandsFree){
1230 
1231     // handle doubles quotes
1232     if (byte == '"'){
1233         hfp_connection->parser_quoted = !hfp_connection->parser_quoted;
1234         return true;
1235     }
1236     if (hfp_connection->parser_quoted) {
1237         hfp_parser_store_byte(hfp_connection, byte);
1238         return true;
1239     }
1240 
1241     // ignore spaces outside command or double quotes (required e.g. for '+CME ERROR:..") command
1242     if ((byte == ' ') && (hfp_connection->parser_state != HFP_PARSER_CMD_HEADER)) return true;
1243 
1244     bool processed = true;
1245 
1246     switch (hfp_connection->parser_state) {
1247         case HFP_PARSER_CMD_HEADER:
1248             switch (byte) {
1249                 case '\n':
1250                 case '\r':
1251                 case ';':
1252                     // ignore separator
1253                     break;
1254                 case ':':
1255                 case '?':
1256                     // store separator
1257                     hfp_parser_store_byte(hfp_connection, byte);
1258                     break;
1259                 case '=':
1260                     // equal sign: remember and wait for next char to decided between '=?' and '=\?'
1261                     hfp_connection->found_equal_sign = true;
1262                     hfp_parser_store_byte(hfp_connection, byte);
1263                     return true;
1264                 default:
1265                     // store if not lookahead
1266                     if (!hfp_connection->found_equal_sign) {
1267                         hfp_parser_store_byte(hfp_connection, byte);
1268                         return true;
1269                     }
1270                     // mark as lookahead
1271                     processed = false;
1272                     break;
1273             }
1274 
1275             // ignore empty tokens
1276             if (hfp_parser_is_buffer_empty(hfp_connection)) return true;
1277 
1278             // parse
1279             hfp_connection->command = parse_command((char *)hfp_connection->line_buffer, isHandsFree);
1280 
1281             // pick +CIND version based on connection state: descriptions during SLC vs. states later
1282             if (hfp_connection->command == HFP_CMD_RETRIEVE_AG_INDICATORS_GENERIC){
1283                 switch(hfp_connection->state){
1284                     case HFP_W4_RETRIEVE_INDICATORS_STATUS:
1285                         hfp_connection->command = HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS;
1286                         break;
1287                     case HFP_W4_RETRIEVE_INDICATORS:
1288                         hfp_connection->command = HFP_CMD_RETRIEVE_AG_INDICATORS;
1289                         break;
1290                     default:
1291                         hfp_connection->command = HFP_CMD_UNKNOWN;
1292                         break;
1293                 }
1294             }
1295 
1296             log_info("command string '%s', handsfree %u -> cmd id %u", (char *)hfp_connection->line_buffer, isHandsFree, hfp_connection->command);
1297 
1298             // next state
1299             hfp_connection->found_equal_sign = false;
1300             hfp_parser_reset_line_buffer(hfp_connection);
1301             hfp_connection->parser_state = HFP_PARSER_CMD_SEQUENCE;
1302 
1303             return processed;
1304 
1305         case HFP_PARSER_CMD_SEQUENCE:
1306             // handle empty fields
1307             if ((byte == ',' ) && (hfp_connection->line_size == 0)){
1308                 hfp_connection->line_buffer[0] = 0;
1309                 hfp_connection->ignore_value = 1;
1310                 parse_sequence(hfp_connection);
1311                 return true;
1312             }
1313 
1314             hfp_parser_store_if_token(hfp_connection, byte);
1315             if (!hfp_parser_is_separator(byte)) return true;
1316 
1317             // ignore empty tokens
1318             switch (hfp_connection->command){
1319                 case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
1320                     // don't ignore empty string
1321                     break;
1322                 default:
1323                     if (hfp_parser_is_buffer_empty(hfp_connection) && (hfp_connection->ignore_value == 0)) {
1324                         return true;
1325                     }
1326                     break;
1327             }
1328 
1329             parse_sequence(hfp_connection);
1330 
1331             hfp_parser_reset_line_buffer(hfp_connection);
1332 
1333             switch (hfp_connection->command){
1334                 case HFP_CMD_AG_SENT_PHONE_NUMBER:
1335                 case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1336                 case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1337                 case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1338                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1339                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1340                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1341                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1342                 case HFP_CMD_HF_INDICATOR_STATUS:
1343                     hfp_connection->parser_state = HFP_PARSER_SECOND_ITEM;
1344                     break;
1345                 default:
1346                     break;
1347             }
1348             return true;
1349 
1350         case HFP_PARSER_SECOND_ITEM:
1351 
1352             hfp_parser_store_if_token(hfp_connection, byte);
1353             if (!hfp_parser_is_separator(byte)) return true;
1354 
1355             switch (hfp_connection->command){
1356                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1357                     log_info("format %s, ", hfp_connection->line_buffer);
1358                     hfp_connection->network_operator.format =  btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1359                     break;
1360                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1361                     log_info("format %s \n", hfp_connection->line_buffer);
1362                     hfp_connection->network_operator.format =  btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1363                     break;
1364                 case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
1365                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
1366                 case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1367                     hfp_connection->generic_status_indicators[hfp_connection->parser_item_index].state = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1368                     break;
1369                 case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1370                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].status = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1371                     log_info("%d \n", hfp_connection->ag_indicators[hfp_connection->parser_item_index].status);
1372                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].status_changed = 1;
1373                     break;
1374                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1375                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].min_range = btstack_atoi((char *)hfp_connection->line_buffer);
1376                     log_info("%s, ", hfp_connection->line_buffer);
1377                     break;
1378                 case HFP_CMD_AG_SENT_PHONE_NUMBER:
1379                 case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1380                 case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1381                     hfp_connection->bnip_type = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1382                     break;
1383                 case HFP_CMD_HF_INDICATOR_STATUS:
1384                     hfp_connection->parser_indicator_value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1385                     break;
1386                 default:
1387                     break;
1388             }
1389 
1390             hfp_parser_reset_line_buffer(hfp_connection);
1391 
1392             hfp_connection->parser_state = HFP_PARSER_THIRD_ITEM;
1393 
1394             return true;
1395 
1396         case HFP_PARSER_THIRD_ITEM:
1397 
1398             hfp_parser_store_if_token(hfp_connection, byte);
1399             if (!hfp_parser_is_separator(byte)) return true;
1400 
1401             switch (hfp_connection->command){
1402                 case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1403                     strncpy(hfp_connection->network_operator.name, (char *)hfp_connection->line_buffer, HFP_MAX_NETWORK_OPERATOR_NAME_SIZE);
1404                     hfp_connection->network_operator.name[HFP_MAX_NETWORK_OPERATOR_NAME_SIZE - 1] = 0;
1405                     log_info("name %s\n", hfp_connection->line_buffer);
1406                     break;
1407                 case HFP_CMD_RETRIEVE_AG_INDICATORS:
1408                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].max_range = btstack_atoi((char *)hfp_connection->line_buffer);
1409                     hfp_next_indicators_index(hfp_connection);
1410                     hfp_connection->ag_indicators_nr = hfp_connection->parser_item_index;
1411                     log_info("%s)\n", hfp_connection->line_buffer);
1412                     break;
1413                 default:
1414                     break;
1415             }
1416 
1417             hfp_parser_reset_line_buffer(hfp_connection);
1418 
1419             if (hfp_connection->command == HFP_CMD_RETRIEVE_AG_INDICATORS){
1420                 hfp_connection->parser_state = HFP_PARSER_CMD_SEQUENCE;
1421             } else {
1422                 hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
1423             }
1424             return true;
1425 
1426         default:
1427             btstack_assert(false);
1428             return true;
1429     }
1430 }
1431 
1432 void hfp_parse(hfp_connection_t * hfp_connection, uint8_t byte, int isHandsFree){
1433     bool processed = false;
1434     while (!processed){
1435         processed = hfp_parse_byte(hfp_connection, byte, isHandsFree);
1436     }
1437     // reset parser state on end-of-line
1438     if (hfp_parser_is_end_of_line(byte)){
1439         hfp_connection->parser_item_index = 0;
1440         hfp_connection->parser_state = HFP_PARSER_CMD_HEADER;
1441     }
1442 }
1443 
1444 static void parse_sequence(hfp_connection_t * hfp_connection){
1445     int value;
1446     switch (hfp_connection->command){
1447         case HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS:
1448             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1449             int i;
1450             switch (hfp_connection->parser_item_index){
1451                 case 0:
1452                     for (i=0;i<hfp_connection->generic_status_indicators_nr;i++){
1453                         if (hfp_connection->generic_status_indicators[i].uuid == value){
1454                             hfp_connection->parser_indicator_index = i;
1455                             break;
1456                         }
1457                     }
1458                     break;
1459                 case 1:
1460                     if (hfp_connection->parser_indicator_index <0) break;
1461                     hfp_connection->generic_status_indicators[hfp_connection->parser_indicator_index].state = value;
1462                     log_info("HFP_CMD_SET_GENERIC_STATUS_INDICATOR_STATUS set indicator at index %u, to %u\n",
1463                      hfp_connection->parser_item_index, value);
1464                     break;
1465                 default:
1466                     break;
1467             }
1468             hfp_next_indicators_index(hfp_connection);
1469             break;
1470 
1471         case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
1472             switch(hfp_connection->parser_item_index){
1473                 case 0:
1474                     // <alpha>: This optional field is not supported, and shall be left blank.
1475                     break;
1476                 case 1:
1477                     // <number>: Quoted string containing the phone number in the format specified by <type>.
1478                     strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1479                     hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1480                     break;
1481                 case 2:
1482                     /*
1483                       <type> field specifies the format of the phone number provided, and can be one of the following values:
1484                       - 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.
1485                      - 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.
1486                      - values 160-175: National number. No prefix nor escape digits included.
1487                      */
1488                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1489                     hfp_connection->bnip_type = value;
1490                     break;
1491                 case 3:
1492                     // <speed>: This optional field is not supported, and shall be left blank.
1493                     break;
1494                 case 4:
1495                     // <service>: Indicates which service this phone number relates to. Shall be either 4 (voice) or 5 (fax).
1496                 default:
1497                     break;
1498             }
1499             // index > 2 are ignored in switch above
1500             hfp_connection->parser_item_index++;
1501             break;
1502         case HFP_CMD_LIST_CURRENT_CALLS:
1503             switch(hfp_connection->parser_item_index){
1504                 case 0:
1505                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1506                     hfp_connection->clcc_idx = value;
1507                     break;
1508                 case 1:
1509                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1510                     hfp_connection->clcc_dir = value;
1511                     break;
1512                 case 2:
1513                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1514                     hfp_connection->clcc_status = value;
1515                     break;
1516                 case 3:
1517                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1518                     hfp_connection->clcc_mode = value;
1519                     break;
1520                 case 4:
1521                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1522                     hfp_connection->clcc_mpty = value;
1523                     break;
1524                 case 5:
1525                     strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1526                     hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1527                     break;
1528                 case 6:
1529                     value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1530                     hfp_connection->bnip_type = value;
1531                     break;
1532                 default:
1533                     break;
1534             }
1535             // index > 6 are ignored in switch above
1536             hfp_connection->parser_item_index++;
1537             break;
1538         case HFP_CMD_SET_MICROPHONE_GAIN:
1539             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1540             hfp_connection->microphone_gain = value;
1541             log_info("hfp parse HFP_CMD_SET_MICROPHONE_GAIN %d\n", value);
1542             break;
1543         case HFP_CMD_SET_SPEAKER_GAIN:
1544             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1545             hfp_connection->speaker_gain = value;
1546             log_info("hfp parse HFP_CMD_SET_SPEAKER_GAIN %d\n", value);
1547             break;
1548         case HFP_CMD_TURN_OFF_EC_AND_NR:
1549             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1550             hfp_connection->ag_echo_and_noise_reduction = value;
1551             log_info("hfp parse HFP_CMD_TURN_OFF_EC_AND_NR %d\n", value);
1552             break;
1553         case HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING:
1554             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1555             hfp_connection->remote_supported_features = store_bit(hfp_connection->remote_supported_features, HFP_AGSF_IN_BAND_RING_TONE, value);
1556             log_info("hfp parse HFP_CHANGE_IN_BAND_RING_TONE_SETTING %d\n", value);
1557             break;
1558         case HFP_CMD_HF_CONFIRMED_CODEC:
1559             hfp_connection->codec_confirmed = btstack_atoi((char*)hfp_connection->line_buffer);
1560             log_info("hfp parse HFP_CMD_HF_CONFIRMED_CODEC %d\n", hfp_connection->codec_confirmed);
1561             break;
1562         case HFP_CMD_AG_SUGGESTED_CODEC:
1563             hfp_connection->suggested_codec = btstack_atoi((char*)hfp_connection->line_buffer);
1564             log_info("hfp parse HFP_CMD_AG_SUGGESTED_CODEC %d\n", hfp_connection->suggested_codec);
1565             break;
1566         case HFP_CMD_SUPPORTED_FEATURES:
1567             hfp_connection->remote_supported_features = btstack_atoi((char*)hfp_connection->line_buffer);
1568             log_info("Parsed supported feature %d\n", (int) hfp_connection->remote_supported_features);
1569             break;
1570         case HFP_CMD_AVAILABLE_CODECS:
1571             log_info("Parsed codec %s\n", hfp_connection->line_buffer);
1572             hfp_connection->remote_codecs[hfp_connection->parser_item_index] = (uint16_t)btstack_atoi((char*)hfp_connection->line_buffer);
1573             hfp_next_codec_index(hfp_connection);
1574             hfp_connection->remote_codecs_nr = hfp_connection->parser_item_index;
1575             break;
1576         case HFP_CMD_RETRIEVE_AG_INDICATORS:
1577             strncpy((char *)hfp_connection->ag_indicators[hfp_connection->parser_item_index].name,  (char *)hfp_connection->line_buffer, HFP_MAX_INDICATOR_DESC_SIZE);
1578             hfp_connection->ag_indicators[hfp_connection->parser_item_index].name[HFP_MAX_INDICATOR_DESC_SIZE-1] = 0;
1579             hfp_connection->ag_indicators[hfp_connection->parser_item_index].index = hfp_connection->parser_item_index+1;
1580             log_info("Indicator %d: %s (", hfp_connection->ag_indicators_nr+1, hfp_connection->line_buffer);
1581             break;
1582         case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
1583             log_info("Parsed Indicator %d with status: %s\n", hfp_connection->parser_item_index+1, hfp_connection->line_buffer);
1584             hfp_connection->ag_indicators[hfp_connection->parser_item_index].status = btstack_atoi((char *) hfp_connection->line_buffer);
1585             hfp_next_indicators_index(hfp_connection);
1586             break;
1587         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
1588             hfp_next_indicators_index(hfp_connection);
1589             if (hfp_connection->parser_item_index != 4) break;
1590             log_info("Parsed Enable indicators: %s\n", hfp_connection->line_buffer);
1591             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1592             hfp_connection->enable_status_update_for_ag_indicators = (uint8_t) value;
1593             break;
1594         case HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES:
1595             log_info("Parsed Support call hold: %s\n", hfp_connection->line_buffer);
1596             if (hfp_connection->line_size > 2 ) break;
1597             memcpy((char *)hfp_connection->remote_call_services[hfp_connection->remote_call_services_index].name, (char *)hfp_connection->line_buffer, HFP_CALL_SERVICE_SIZE-1);
1598             hfp_connection->remote_call_services[hfp_connection->remote_call_services_index].name[HFP_CALL_SERVICE_SIZE - 1] = 0;
1599             hfp_next_remote_call_services_index(hfp_connection);
1600             break;
1601         case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
1602         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
1603             log_info("Parsed Generic status indicator: %s\n", hfp_connection->line_buffer);
1604             hfp_connection->generic_status_indicators[hfp_connection->parser_item_index].uuid = (uint16_t)btstack_atoi((char*)hfp_connection->line_buffer);
1605             hfp_next_indicators_index(hfp_connection);
1606             hfp_connection->generic_status_indicators_nr = hfp_connection->parser_item_index;
1607             break;
1608         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
1609             // HF parses inital AG gen. ind. state
1610             log_info("Parsed List generic status indicator %s state: ", hfp_connection->line_buffer);
1611             hfp_connection->parser_item_index = hfp_parse_indicator_index(hfp_connection);
1612             break;
1613         case HFP_CMD_HF_INDICATOR_STATUS:
1614             hfp_connection->parser_indicator_index = hfp_parse_indicator_index(hfp_connection);
1615             log_info("Parsed HF indicator index %u", hfp_connection->parser_indicator_index);
1616             break;
1617         case HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE:
1618             // AG parses new gen. ind. state
1619             if (hfp_connection->ignore_value){
1620                 hfp_connection->ignore_value = 0;
1621                 log_info("Parsed Enable AG indicator pos %u('%s') - unchanged (stays %u)\n", hfp_connection->parser_item_index,
1622                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].name, hfp_connection->ag_indicators[hfp_connection->parser_item_index].enabled);
1623             }
1624             else if (hfp_connection->ag_indicators[hfp_connection->parser_item_index].mandatory){
1625                 log_info("Parsed Enable AG indicator pos %u('%s') - ignore (mandatory)\n",
1626                     hfp_connection->parser_item_index, hfp_connection->ag_indicators[hfp_connection->parser_item_index].name);
1627             } else {
1628                 value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1629                 hfp_connection->ag_indicators[hfp_connection->parser_item_index].enabled = value;
1630                 log_info("Parsed Enable AG indicator pos %u('%s'): %u\n", hfp_connection->parser_item_index,
1631                     hfp_connection->ag_indicators[hfp_connection->parser_item_index].name, value);
1632             }
1633             hfp_next_indicators_index(hfp_connection);
1634             break;
1635         case HFP_CMD_TRANSFER_AG_INDICATOR_STATUS:
1636             // indicators are indexed starting with 1
1637             hfp_connection->parser_item_index = hfp_parse_indicator_index(hfp_connection);
1638             log_info("Parsed status of the AG indicator %d, status ", hfp_connection->parser_item_index);
1639             break;
1640         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1641             hfp_connection->network_operator.mode = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1642             log_info("Parsed network operator mode: %d, ", hfp_connection->network_operator.mode);
1643             break;
1644         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1645             if (hfp_connection->line_buffer[0] == '3'){
1646                 log_info("Parsed Set network operator format : %s, ", hfp_connection->line_buffer);
1647                 break;
1648             }
1649             // TODO emit ERROR, wrong format
1650             log_info("ERROR Set network operator format: index %s not supported\n", hfp_connection->line_buffer);
1651             break;
1652         case HFP_CMD_ERROR:
1653             break;
1654         case HFP_CMD_EXTENDED_AUDIO_GATEWAY_ERROR:
1655             hfp_connection->extended_audio_gateway_error = 1;
1656             hfp_connection->extended_audio_gateway_error_value = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1657             break;
1658         case HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR:
1659             hfp_connection->enable_extended_audio_gateway_error_report = (uint8_t)btstack_atoi((char*)hfp_connection->line_buffer);
1660             hfp_connection->ok_pending = 1;
1661             hfp_connection->extended_audio_gateway_error = 0;
1662             break;
1663         case HFP_CMD_AG_SENT_PHONE_NUMBER:
1664         case HFP_CMD_AG_SENT_CALL_WAITING_NOTIFICATION_UPDATE:
1665         case HFP_CMD_AG_SENT_CLIP_INFORMATION:
1666             strncpy(hfp_connection->bnip_number, (char *)hfp_connection->line_buffer, sizeof(hfp_connection->bnip_number));
1667             hfp_connection->bnip_number[sizeof(hfp_connection->bnip_number)-1] = 0;
1668             break;
1669         case HFP_CMD_CALL_HOLD:
1670             hfp_connection->ag_call_hold_action = hfp_connection->line_buffer[0] - '0';
1671             if (hfp_connection->line_buffer[1] != '\0'){
1672                 hfp_connection->call_index = btstack_atoi((char *)&hfp_connection->line_buffer[1]);
1673             }
1674             break;
1675         case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
1676             hfp_connection->ag_response_and_hold_action = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1677             break;
1678         case HFP_CMD_TRANSMIT_DTMF_CODES:
1679             hfp_connection->ag_dtmf_code = hfp_connection->line_buffer[0];
1680             break;
1681         case HFP_CMD_ENABLE_CLIP:
1682             hfp_connection->clip_enabled = hfp_connection->line_buffer[0] != '0';
1683             break;
1684         case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
1685             hfp_connection->call_waiting_notification_enabled = hfp_connection->line_buffer[0] != '0';
1686             break;
1687         case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
1688             value = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1689             hfp_connection->ag_activate_voice_recognition_value = value;
1690             break;
1691         case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
1692             switch(hfp_connection->parser_item_index){
1693                 case 0:
1694                     hfp_connection->ag_vra_status = btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1695                     break;
1696                 case 1:
1697                     hfp_connection->ag_vra_state = (hfp_voice_recognition_state_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1698                     break;
1699                 case 2:
1700                     hfp_connection->ag_msg.text_id = 0;
1701                     for (i = 0 ; i < 4; i++){
1702                         hfp_connection->ag_msg.text_id = (hfp_connection->ag_msg.text_id << 4) | nibble_for_char(hfp_connection->line_buffer[i]);
1703                     }
1704                     break;
1705                 case 3:
1706                     hfp_connection->ag_msg.text_type = (hfp_text_type_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1707                     break;
1708                 case 4:
1709                     hfp_connection->ag_msg.text_operation = (hfp_text_operation_t) btstack_atoi((char *)&hfp_connection->line_buffer[0]);
1710                     break;
1711                 case 5:
1712                     hfp_connection->line_buffer[hfp_connection->line_size] = 0;
1713                     hfp_connection->ag_vra_msg_length = hfp_connection->line_size + 1;
1714                     break;
1715                 default:
1716                     break;
1717             }
1718             hfp_connection->parser_item_index++;
1719             break;
1720         default:
1721             break;
1722     }
1723 }
1724 
1725 static void hfp_handle_start_sdp_client_query(void * context){
1726     UNUSED(context);
1727 
1728     btstack_linked_list_iterator_t it;
1729     btstack_linked_list_iterator_init(&it, &hfp_connections);
1730     while (btstack_linked_list_iterator_has_next(&it)){
1731         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1732 
1733         if (connection->state != HFP_W2_SEND_SDP_QUERY) continue;
1734 
1735         connection->state = HFP_W4_SDP_QUERY_COMPLETE;
1736         hfp_sdp_query_context.local_role = connection->local_role;
1737         (void)memcpy(hfp_sdp_query_context.remote_address, connection->remote_addr, 6);
1738         sdp_client_query_rfcomm_channel_and_name_for_service_class_uuid(&handle_query_rfcomm_event, connection->remote_addr, connection->service_uuid);
1739         return;
1740     }
1741 }
1742 
1743 uint8_t hfp_establish_service_level_connection(bd_addr_t bd_addr, uint16_t service_uuid, hfp_role_t local_role){
1744     hfp_connection_t * connection = get_hfp_connection_context_for_bd_addr(bd_addr, local_role);
1745     if (connection){
1746         return ERROR_CODE_COMMAND_DISALLOWED;
1747     }
1748 
1749     connection = hfp_create_connection(bd_addr, local_role);
1750     if (!connection){
1751         return BTSTACK_MEMORY_ALLOC_FAILED;
1752     }
1753 
1754     connection->state = HFP_W2_SEND_SDP_QUERY;
1755 
1756     bd_addr_copy(connection->remote_addr, bd_addr);
1757     connection->service_uuid = service_uuid;
1758 
1759     hfp_sdp_query_request.callback = &hfp_handle_start_sdp_client_query;
1760     // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
1761     (void) sdp_client_register_query_callback(&hfp_sdp_query_request);
1762     return ERROR_CODE_SUCCESS;
1763 }
1764 
1765 void hfp_trigger_release_service_level_connection(hfp_connection_t * hfp_connection){
1766     // called internally, NULL check already performed
1767     btstack_assert(hfp_connection != NULL);
1768 
1769     hfp_trigger_release_audio_connection(hfp_connection);
1770     if (hfp_connection->state < HFP_W4_RFCOMM_CONNECTED){
1771         hfp_connection->state = HFP_IDLE;
1772         return;
1773     }
1774 
1775     if (hfp_connection->state == HFP_W4_RFCOMM_CONNECTED){
1776         hfp_connection->state = HFP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
1777         return;
1778     }
1779     hfp_connection->release_slc_connection = 1;
1780     if (hfp_connection->state < HFP_W4_SCO_CONNECTED){
1781         hfp_connection->state = HFP_W2_DISCONNECT_RFCOMM;
1782         return;
1783     }
1784 
1785     if (hfp_connection->state < HFP_W4_SCO_DISCONNECTED){
1786         hfp_connection->state = HFP_W2_DISCONNECT_SCO;
1787         hfp_connection->release_audio_connection = 1;
1788         return;
1789     }
1790 }
1791 
1792 uint8_t hfp_trigger_release_audio_connection(hfp_connection_t * hfp_connection){
1793     // called internally, NULL check already performed
1794     btstack_assert(hfp_connection != NULL);
1795     if (hfp_connection->state <= HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED){
1796         return ERROR_CODE_COMMAND_DISALLOWED;
1797     }
1798     switch (hfp_connection->state) {
1799         case HFP_W2_CONNECT_SCO:
1800             hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
1801             break;
1802         case HFP_W4_SCO_CONNECTED:
1803         case HFP_AUDIO_CONNECTION_ESTABLISHED:
1804             hfp_connection->release_audio_connection = 1;
1805             break;
1806         default:
1807             return ERROR_CODE_COMMAND_DISALLOWED;
1808     }
1809     return ERROR_CODE_SUCCESS;
1810 }
1811 
1812 static const struct link_settings {
1813     const uint16_t max_latency;
1814     const uint8_t  retransmission_effort;
1815     const uint16_t packet_types;
1816     const bool     eSCO;
1817     const uint8_t  codec;
1818 } hfp_link_settings [] = {
1819     { 0xffff, 0xff, SCO_PACKET_TYPES_HV1,  false, HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_D0
1820     { 0xffff, 0xff, SCO_PACKET_TYPES_HV3,  false, HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_D1
1821     { 0x0007, 0x01, SCO_PACKET_TYPES_EV3,  true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S1
1822     { 0x0007, 0x01, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S2
1823     { 0x000a, 0x01, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S3
1824     { 0x000c, 0x02, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_CVSD }, // HFP_LINK_SETTINGS_S4
1825     { 0x0008, 0x02, SCO_PACKET_TYPES_EV3,  true,  HFP_CODEC_MSBC }, // HFP_LINK_SETTINGS_T1
1826     { 0x000d, 0x02, SCO_PACKET_TYPES_2EV3, true,  HFP_CODEC_MSBC }  // HFP_LINK_SETTINGS_T2
1827 };
1828 
1829 void hfp_setup_synchronous_connection(hfp_connection_t * hfp_connection){
1830     // all packet types, fixed bandwidth
1831     int setting = hfp_connection->link_setting;
1832     log_info("hfp_setup_synchronous_connection using setting nr %u", setting);
1833     hfp_sco_establishment_active = hfp_connection;
1834     uint16_t sco_voice_setting = hci_get_sco_voice_setting();
1835     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1836 #ifdef ENABLE_BCM_PCM_WBS
1837         sco_voice_setting = 0x0063; // Transparent data, 16-bit for BCM controllers
1838 #else
1839         sco_voice_setting = 0x0043; // Transparent data, 8-bit otherwise
1840 #endif
1841     }
1842     // get packet types - bits 6-9 are 'don't allow'
1843     uint16_t packet_types = hfp_link_settings[setting].packet_types ^ 0x03c0;
1844     hci_send_cmd(&hci_setup_synchronous_connection, hfp_connection->acl_handle, 8000, 8000, hfp_link_settings[setting].max_latency,
1845         sco_voice_setting, hfp_link_settings[setting].retransmission_effort, packet_types);
1846 }
1847 
1848 void hfp_accept_synchronous_connection(hfp_connection_t * hfp_connection, bool incoming_eSCO){
1849 
1850     // remote supported feature eSCO is set if link type is eSCO
1851     // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
1852     uint16_t max_latency;
1853     uint8_t  retransmission_effort;
1854     uint16_t packet_types;
1855 
1856     if (incoming_eSCO && hci_extended_sco_link_supported() && hci_remote_esco_supported(hfp_connection->acl_handle)){
1857         max_latency = 0x000c;
1858         retransmission_effort = 0x02;
1859         // eSCO: EV3 and 2-EV3
1860         packet_types = 0x0048;
1861     } else {
1862         max_latency = 0xffff;
1863         retransmission_effort = 0xff;
1864         // sco: HV1 and HV3
1865         packet_types = 0x005;
1866     }
1867 
1868     // mSBC only allows for transparent data
1869     uint16_t sco_voice_setting = hci_get_sco_voice_setting();
1870     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1871 #ifdef ENABLE_BCM_PCM_WBS
1872         sco_voice_setting = 0x0063; // Transparent data, 16-bit for BCM controllers
1873 #else
1874         sco_voice_setting = 0x0043; // Transparent data, 8-bit otherwise
1875 #endif
1876     }
1877 
1878     // filter packet types
1879     packet_types &= hfp_get_sco_packet_types();
1880 
1881     // bits 6-9 are 'don't allow'
1882     packet_types ^= 0x3c0;
1883 
1884     log_info("HFP: sending hci_accept_connection_request, packet types 0x%04x, sco_voice_setting 0x%02x", packet_types, sco_voice_setting);
1885     hci_send_cmd(&hci_accept_synchronous_connection, hfp_connection->remote_addr, 8000, 8000, max_latency,
1886                  sco_voice_setting, retransmission_effort, packet_types);
1887 }
1888 
1889 #ifdef ENABLE_CC256X_ASSISTED_HFP
1890 void hfp_cc256x_prepare_for_sco(hfp_connection_t * hfp_connection){
1891     hfp_connection->cc256x_send_write_codec_config = true;
1892     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1893         hfp_connection->cc256x_send_wbs_associate = true;
1894     }
1895 }
1896 
1897 void hfp_cc256x_write_codec_config(hfp_connection_t * hfp_connection){
1898     uint32_t sample_rate_hz;
1899     uint16_t clock_rate_khz;
1900     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1901         clock_rate_khz = 512;
1902         sample_rate_hz = 16000;
1903     } else {
1904         clock_rate_khz = 256;
1905         sample_rate_hz = 8000;
1906     }
1907     uint8_t clock_direction = 0;        // master
1908     uint16_t frame_sync_duty_cycle = 0; // i2s with 50%
1909     uint8_t  frame_sync_edge = 1;       // rising edge
1910     uint8_t  frame_sync_polarity = 0;   // active high
1911     uint8_t  reserved = 0;
1912     uint16_t size = 16;
1913     uint16_t chan_1_offset = 1;
1914     uint16_t chan_2_offset = chan_1_offset + size;
1915     uint8_t  out_edge = 1;              // rising
1916     uint8_t  in_edge = 0;               // falling
1917     hci_send_cmd(&hci_ti_write_codec_config, clock_rate_khz, clock_direction, sample_rate_hz, frame_sync_duty_cycle,
1918                  frame_sync_edge, frame_sync_polarity, reserved,
1919                  size, chan_1_offset, out_edge, size, chan_1_offset, in_edge, reserved,
1920                  size, chan_2_offset, out_edge, size, chan_2_offset, in_edge, reserved);
1921 }
1922 #endif
1923 
1924 #ifdef ENABLE_BCM_PCM_WBS
1925 void hfp_bcm_prepare_for_sco(hfp_connection_t * hfp_connection){
1926     hfp_connection->bcm_send_write_i2spcm_interface_param = true;
1927     if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
1928         hfp_connection->bcm_send_enable_wbs = true;
1929     }
1930 }
1931 void hfp_bcm_write_i2spcm_interface_param(hfp_connection_t * hfp_connection){
1932     uint8_t sample_rate = (hfp_connection->negotiated_codec == HFP_CODEC_MSBC) ? 1 : 0;
1933     // i2s enable, master, 8/16 kHz, 512 kHz
1934     hci_send_cmd(&hci_bcm_write_i2spcm_interface_paramhci_bcm_write_i2spcm_interface_param, 1, 1, sample_rate, 2);
1935 }
1936 #endif
1937 
1938 void hfp_set_hf_callback(btstack_packet_handler_t callback){
1939     hfp_hf_callback = callback;
1940 }
1941 
1942 void hfp_set_ag_callback(btstack_packet_handler_t callback){
1943     hfp_ag_callback = callback;
1944 }
1945 
1946 void hfp_set_ag_rfcomm_packet_handler(btstack_packet_handler_t handler){
1947     hfp_ag_rfcomm_packet_handler = handler;
1948 }
1949 
1950 void hfp_set_hf_rfcomm_packet_handler(btstack_packet_handler_t handler){
1951     hfp_hf_rfcomm_packet_handler = handler;
1952 }
1953 
1954 void hfp_init(void){
1955     hfp_allowed_sco_packet_types = SCO_PACKET_TYPES_ALL;
1956 }
1957 
1958 void hfp_deinit(void){
1959     hfp_allowed_sco_packet_types = 0;
1960     hfp_connections = NULL;
1961     hfp_hf_callback = NULL;
1962     hfp_ag_callback = NULL;
1963     hfp_hf_rfcomm_packet_handler = NULL;
1964     hfp_ag_rfcomm_packet_handler = NULL;
1965     hfp_sco_establishment_active = NULL;
1966     (void) memset(&hfp_sdp_query_context, 0, sizeof(hfp_sdp_query_context_t));
1967     (void) memset(&hfp_sdp_query_request, 0, sizeof(btstack_context_callback_registration_t));
1968 }
1969 
1970 void hfp_set_sco_packet_types(uint16_t packet_types){
1971     hfp_allowed_sco_packet_types = packet_types;
1972 }
1973 
1974 uint16_t hfp_get_sco_packet_types(void){
1975     return hfp_allowed_sco_packet_types;
1976 }
1977 
1978 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){
1979     int8_t setting = (int8_t) current_setting;
1980     bool can_use_eSCO = local_eSCO_supported && remote_eSCO_supported;
1981     while (setting > 0){
1982         setting--;
1983         // skip if eSCO required but not available
1984         if (hfp_link_settings[setting].eSCO && !can_use_eSCO) continue;
1985         // skip if S4 but not supported
1986         if ((setting == (int8_t) HFP_LINK_SETTINGS_S4) && !eSCO_S4_supported) continue;
1987         // skip wrong codec
1988         if ( hfp_link_settings[setting].codec != negotiated_codec) continue;
1989         // skip disabled packet types
1990         uint16_t required_packet_types = hfp_link_settings[setting].packet_types;
1991         uint16_t allowed_packet_types  = hfp_allowed_sco_packet_types;
1992         if ((required_packet_types & allowed_packet_types) == 0) continue;
1993 
1994         // found matching setting
1995         return (hfp_link_settings_t) setting;
1996     }
1997     return HFP_LINK_SETTINGS_NONE;
1998 }
1999 
2000 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){
2001     bool local_eSCO_supported  = hci_extended_sco_link_supported();
2002     bool remote_eSCO_supported = hci_remote_esco_supported(hfp_connection->acl_handle);
2003     uint8_t negotiated_codec   = hfp_connection->negotiated_codec;
2004     return  hfp_next_link_setting(current_setting, local_eSCO_supported, remote_eSCO_supported, eSCO_S4_supported, negotiated_codec);
2005 }
2006 
2007 void hfp_init_link_settings(hfp_connection_t * hfp_connection, uint8_t eSCO_S4_supported){
2008     // get highest possible link setting
2009     hfp_connection->link_setting = hfp_next_link_setting_for_connection(HFP_LINK_SETTINGS_NONE, hfp_connection, eSCO_S4_supported);
2010     log_info("hfp_init_link_settings: %u", hfp_connection->link_setting);
2011 }
2012 
2013 #define HFP_HF_RX_DEBUG_PRINT_LINE 80
2014 
2015 void hfp_log_rfcomm_message(const char * tag, uint8_t * packet, uint16_t size){
2016 #ifdef ENABLE_LOG_INFO
2017     // encode \n\r
2018     char printable[HFP_HF_RX_DEBUG_PRINT_LINE+2];
2019     int i = 0;
2020     int pos;
2021     for (pos=0 ; (pos < size) && (i < (HFP_HF_RX_DEBUG_PRINT_LINE - 3)) ; pos++){
2022         switch (packet[pos]){
2023             case '\n':
2024                 printable[i++] = '\\';
2025                 printable[i++] = 'n';
2026                 break;
2027             case '\r':
2028                 printable[i++] = '\\';
2029                 printable[i++] = 'r';
2030                 break;
2031             default:
2032                 printable[i++] = packet[pos];
2033                 break;
2034         }
2035     }
2036     printable[i] = 0;
2037     log_info("%s: '%s'", tag, printable);
2038 #endif
2039 }
2040