xref: /btstack/src/classic/hfp_ag.c (revision db88441f671cf9b797d1a7638cc0e38d13db6ac0)
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_ag.c"
39 
40 // *****************************************************************************
41 //
42 // HFP Audio Gateway (AG) unit
43 //
44 // *****************************************************************************
45 
46 #include "btstack_config.h"
47 
48 #include <stdint.h>
49 #include <stdio.h>
50 #include <string.h>
51 
52 #include "hci_cmd.h"
53 #include "btstack_run_loop.h"
54 
55 #include "bluetooth_sdp.h"
56 #include "hci.h"
57 #include "btstack_memory.h"
58 #include "hci_dump.h"
59 #include "l2cap.h"
60 #include "btstack_debug.h"
61 #include "btstack_event.h"
62 #include "classic/core.h"
63 #include "classic/hfp.h"
64 #include "classic/hfp_ag.h"
65 #include "classic/hfp_gsm_model.h"
66 #include "classic/sdp_client_rfcomm.h"
67 #include "classic/sdp_server.h"
68 #include "classic/sdp_util.h"
69 
70 // private prototypes
71 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection);
72 static void hfp_ag_hf_start_ringing_incoming(hfp_connection_t * hfp_connection);
73 static void hfp_ag_hf_start_ringing_outgoing(hfp_connection_t * hfp_connection);
74 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection);
75 
76 // public prototypes
77 hfp_generic_status_indicator_t * get_hfp_generic_status_indicators(void);
78 int get_hfp_generic_status_indicators_nr(void);
79 void set_hfp_generic_status_indicators(hfp_generic_status_indicator_t * indicators, int indicator_nr);
80 void set_hfp_ag_indicators(hfp_ag_indicator_t * indicators, int indicator_nr);
81 int get_hfp_ag_indicators_nr(hfp_connection_t * context);
82 hfp_ag_indicator_t * get_hfp_ag_indicators(hfp_connection_t * context);
83 
84 #define HFP_SUBEVENT_INVALID 0xFFFF
85 
86 // const
87 static const char hfp_ag_default_service_name[] = "Voice gateway";
88 
89 // globals
90 
91 // higher layer callbacks
92 static btstack_packet_handler_t hfp_ag_callback;
93 
94 static bool (*hfp_ag_custom_call_sm_handler)(hfp_ag_call_event_t event);
95 
96 static btstack_packet_callback_registration_t hfp_ag_hci_event_callback_registration;
97 
98 static uint16_t hfp_ag_supported_features;
99 
100 // in-band ring tone is active on SLC if supported
101 static bool hfp_ag_in_band_ring_tone_active;
102 
103 // codecs
104 static uint8_t hfp_ag_codecs_nr;
105 static uint8_t hfp_ag_codecs[HFP_MAX_NUM_CODECS];
106 
107 // AG indicators
108 static int                hfp_ag_indicators_nr;
109 static hfp_ag_indicator_t hfp_ag_indicators[HFP_MAX_NUM_INDICATORS];
110 
111 // generic status indicators
112 static int                            hfp_ag_generic_status_indicators_nr;
113 static hfp_generic_status_indicator_t hfp_ag_generic_status_indicators[HFP_MAX_NUM_INDICATORS];
114 
115 static int    hfp_ag_call_hold_services_nr;
116 static char * hfp_ag_call_hold_services[6];
117 
118 static hfp_response_and_hold_state_t hfp_ag_response_and_hold_state;
119 static bool hfp_ag_response_and_hold_active = false;
120 
121 // Subscriber information entries
122 static hfp_phone_number_t * hfp_ag_subscriber_numbers;
123 static int                  hfp_ag_subscriber_numbers_count;
124 
125 // call state
126 static btstack_timer_source_t hfp_ag_ring_timeout;
127 
128 // code
129 static int hfp_ag_get_ag_indicators_nr(hfp_connection_t * hfp_connection){
130     if (hfp_connection->ag_indicators_nr != hfp_ag_indicators_nr){
131         hfp_connection->ag_indicators_nr = hfp_ag_indicators_nr;
132         (void)memcpy(hfp_connection->ag_indicators, hfp_ag_indicators,
133                      hfp_ag_indicators_nr * sizeof(hfp_ag_indicator_t));
134     }
135     return hfp_connection->ag_indicators_nr;
136 }
137 
138 hfp_ag_indicator_t * hfp_ag_get_ag_indicators(hfp_connection_t * hfp_connection){
139     // TODO: save only value, and value changed in the hfp_connection?
140     if (hfp_connection->ag_indicators_nr != hfp_ag_indicators_nr){
141         hfp_connection->ag_indicators_nr = hfp_ag_indicators_nr;
142         (void)memcpy(hfp_connection->ag_indicators, hfp_ag_indicators,
143                      hfp_ag_indicators_nr * sizeof(hfp_ag_indicator_t));
144     }
145     return (hfp_ag_indicator_t *)&(hfp_connection->ag_indicators);
146 }
147 
148 static hfp_ag_indicator_t * get_ag_indicator_for_name(const char * name){
149     int i;
150     for (i = 0; i < hfp_ag_indicators_nr; i++){
151         if (strcmp(hfp_ag_indicators[i].name, name) == 0){
152             return &hfp_ag_indicators[i];
153         }
154     }
155     return NULL;
156 }
157 
158 static int get_ag_indicator_index_for_name(const char * name){
159     int i;
160     for (i = 0; i < hfp_ag_indicators_nr; i++){
161         if (strcmp(hfp_ag_indicators[i].name, name) == 0){
162             return i;
163         }
164     }
165     return -1;
166 }
167 
168 static hfp_connection_t * get_hfp_ag_connection_context_for_acl_handle(uint16_t handle){
169     btstack_linked_list_iterator_t it;
170     btstack_linked_list_iterator_init(&it, hfp_get_connections());
171     while (btstack_linked_list_iterator_has_next(&it)){
172         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
173         if (hfp_connection->acl_handle != handle)      continue;
174         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
175         return hfp_connection;
176     }
177     return NULL;
178 }
179 
180 static bool has_in_band_ring_tone(void){
181     return get_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE) != 0;
182 }
183 
184 static int use_in_band_tone(hfp_connection_t *hfp_connection) {
185     return hfp_connection->ag_in_band_ring_tone_active ? 1 : 0;
186 }
187 
188 static int has_codec_negotiation_feature(hfp_connection_t * hfp_connection){
189     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_CODEC_NEGOTIATION);
190     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_CODEC_NEGOTIATION);
191     return hf && ag;
192 }
193 
194 static int has_call_waiting_and_3way_calling_feature(hfp_connection_t * hfp_connection){
195     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_THREE_WAY_CALLING);
196     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_THREE_WAY_CALLING);
197     return hf && ag;
198 }
199 
200 static int has_hf_indicators_feature(hfp_connection_t * hfp_connection){
201     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_HF_INDICATORS);
202     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_HF_INDICATORS);
203     return hf && ag;
204 }
205 
206 /* unsolicited responses */
207 
208 static int hfp_ag_send_change_in_band_ring_tone_setting_cmd(hfp_connection_t * hfp_connection){
209     char buffer[40];
210     snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n",
211              HFP_CHANGE_IN_BAND_RING_TONE_SETTING, use_in_band_tone(hfp_connection));
212     buffer[sizeof(buffer) - 1] = 0;
213     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
214 }
215 
216 static int hfp_ag_exchange_supported_features_cmd(uint16_t cid){
217     char buffer[40];
218     snprintf(buffer, sizeof(buffer), "\r\n%s:%d\r\n\r\nOK\r\n",
219              HFP_SUPPORTED_FEATURES, hfp_ag_supported_features);
220     buffer[sizeof(buffer) - 1] = 0;
221     return send_str_over_rfcomm(cid, buffer);
222 }
223 
224 static int hfp_ag_send_ok(uint16_t cid){
225     char buffer[10];
226     snprintf(buffer, sizeof(buffer), "\r\nOK\r\n");
227     buffer[sizeof(buffer) - 1] = 0;
228     return send_str_over_rfcomm(cid, buffer);
229 }
230 
231 static int hfp_ag_send_ring(uint16_t cid){
232     return send_str_over_rfcomm(cid, (char *) "\r\nRING\r\n");
233 }
234 
235 static int hfp_ag_send_no_carrier(uint16_t cid){
236     char buffer[15];
237     snprintf(buffer, sizeof(buffer), "\r\nNO CARRIER\r\n");
238     buffer[sizeof(buffer) - 1] = 0;
239     return send_str_over_rfcomm(cid, buffer);
240 }
241 
242 static int hfp_ag_send_clip(uint16_t cid){
243     char buffer[50];
244     snprintf(buffer, sizeof(buffer), "\r\n%s: \"%s\",%u\r\n", HFP_ENABLE_CLIP,
245              hfp_gsm_clip_number(), hfp_gsm_clip_type());
246     buffer[sizeof(buffer) - 1] = 0;
247     return send_str_over_rfcomm(cid, buffer);
248 }
249 
250 static int hfp_send_subscriber_number_cmd(uint16_t cid, uint8_t type, const char * number){
251     char buffer[50];
252     snprintf(buffer, sizeof(buffer), "\r\n%s: ,\"%s\",%u, , \r\n",
253              HFP_SUBSCRIBER_NUMBER_INFORMATION, number, type);
254     buffer[sizeof(buffer) - 1] = 0;
255     return send_str_over_rfcomm(cid, buffer);
256 }
257 
258 static int hfp_ag_send_phone_number_for_voice_tag_cmd(uint16_t cid){
259     char buffer[50];
260     snprintf(buffer, sizeof(buffer), "\r\n%s: %s\r\n",
261              HFP_PHONE_NUMBER_FOR_VOICE_TAG, hfp_gsm_clip_number());
262     buffer[sizeof(buffer) - 1] = 0;
263     return send_str_over_rfcomm(cid, buffer);
264 }
265 
266 static int hfp_ag_send_call_waiting_notification(uint16_t cid){
267     char buffer[50];
268     snprintf(buffer, sizeof(buffer), "\r\n%s: \"%s\",%u\r\n",
269              HFP_ENABLE_CALL_WAITING_NOTIFICATION, hfp_gsm_clip_number(),
270              hfp_gsm_clip_type());
271     buffer[sizeof(buffer) - 1] = 0;
272     return send_str_over_rfcomm(cid, buffer);
273 }
274 
275 static int hfp_ag_send_error(uint16_t cid){
276     char buffer[10];
277     snprintf(buffer, sizeof(buffer), "\r\nERROR\r\n");
278     buffer[sizeof(buffer) - 1] = 0;
279     return send_str_over_rfcomm(cid, buffer);
280 }
281 
282 static int hfp_ag_send_report_extended_audio_gateway_error(uint16_t cid, uint8_t error){
283     char buffer[20];
284     snprintf(buffer, sizeof(buffer), "\r\n%s=%d\r\n",
285              HFP_EXTENDED_AUDIO_GATEWAY_ERROR, error);
286     buffer[sizeof(buffer) - 1] = 0;
287     return send_str_over_rfcomm(cid, buffer);
288 }
289 
290 // get size for indicator string
291 static int hfp_ag_indicators_string_size(hfp_connection_t * hfp_connection, int i){
292     // template: ("$NAME",($MIN,$MAX))
293     return 8 + (int) strlen(hfp_ag_get_ag_indicators(hfp_connection)[i].name)
294          + string_len_for_uint32(hfp_ag_get_ag_indicators(hfp_connection)[i].min_range)
295          + string_len_for_uint32(hfp_ag_get_ag_indicators(hfp_connection)[i].min_range);
296 }
297 
298 // store indicator
299 static void hfp_ag_indicators_string_store(hfp_connection_t * hfp_connection, int i, uint8_t * buffer, uint16_t buffer_size){
300     snprintf((char *)buffer, buffer_size, "(\"%s\",(%d,%d)),",
301              hfp_ag_get_ag_indicators(hfp_connection)[i].name,
302              hfp_ag_get_ag_indicators(hfp_connection)[i].min_range,
303              hfp_ag_get_ag_indicators(hfp_connection)[i].max_range);
304     ((char *)buffer)[buffer_size - 1] = 0;
305 }
306 
307 // structure: header [indicator [comma indicator]] footer
308 static int hfp_ag_indicators_cmd_generator_num_segments(hfp_connection_t * hfp_connection){
309     int num_indicators = hfp_ag_get_ag_indicators_nr(hfp_connection);
310     if (!num_indicators) return 2;
311     return 3 + ((num_indicators-1) * 2);
312 }
313 
314 // get size of individual segment for hfp_ag_retrieve_indicators_cmd
315 static int hfp_ag_indicators_cmd_generator_get_segment_len(hfp_connection_t * hfp_connection, int index){
316     if (index == 0) {
317         return (uint16_t) strlen(HFP_INDICATOR) + 3;   // "\n\r%s:""
318     }
319     index--;
320     int num_indicators = hfp_ag_get_ag_indicators_nr(hfp_connection);
321     int indicator_index = index >> 1;
322     if ((index & 1) == 0){
323         return hfp_ag_indicators_string_size(hfp_connection, indicator_index);
324     }
325     if (indicator_index == (num_indicators - 1)){
326         return 8; // "\r\n\r\nOK\r\n"
327     }
328     return 1; // comma
329 }
330 
331 static void hfp_ag_indicators_cmd_generator_store_segment(hfp_connection_t * hfp_connection, int index, uint8_t * buffer, uint16_t buffer_size){
332     if (index == 0){
333         *buffer++ = '\r';
334         *buffer++ = '\n';
335         int len = (uint16_t) strlen(HFP_INDICATOR);
336         (void)memcpy(buffer, HFP_INDICATOR, len);
337         buffer += len;
338         *buffer++ = ':';
339         return;
340     }
341     index--;
342     int num_indicators = hfp_ag_get_ag_indicators_nr(hfp_connection);
343     int indicator_index = index >> 1;
344     if ((index & 1) == 0){
345         hfp_ag_indicators_string_store(hfp_connection, indicator_index, buffer, buffer_size);
346         return;
347     }
348     if (indicator_index == (num_indicators-1)){
349         (void)memcpy(buffer, "\r\n\r\nOK\r\n", 8);
350         return;
351     }
352     *buffer = ',';
353 }
354 
355 static int hfp_ag_generic_indicators_join(char * buffer, int buffer_size){
356     if (buffer_size < (hfp_ag_indicators_nr * 3)) return 0;
357     int i;
358     int offset = 0;
359     for (i = 0; i < (hfp_ag_generic_status_indicators_nr - 1); i++) {
360         offset += snprintf(buffer+offset, buffer_size-offset, "%d,", hfp_ag_generic_status_indicators[i].uuid);
361     }
362     if (i < hfp_ag_generic_status_indicators_nr){
363         offset += snprintf(buffer+offset, buffer_size-offset, "%d", hfp_ag_generic_status_indicators[i].uuid);
364     }
365     return offset;
366 }
367 
368 static int hfp_ag_generic_indicators_initial_status_join(char * buffer, int buffer_size){
369     if (buffer_size < (hfp_ag_generic_status_indicators_nr * 3)) return 0;
370     int i;
371     int offset = 0;
372     for (i = 0; i < hfp_ag_generic_status_indicators_nr; i++) {
373         offset += snprintf(buffer+offset, buffer_size-offset, "\r\n%s:%d,%d\r\n", HFP_GENERIC_STATUS_INDICATOR, hfp_ag_generic_status_indicators[i].uuid, hfp_ag_generic_status_indicators[i].state);
374     }
375     return offset;
376 }
377 
378 static int hfp_ag_indicators_status_join(char * buffer, int buffer_size){
379     if (buffer_size < (hfp_ag_indicators_nr * 3)) return 0;
380     int i;
381     int offset = 0;
382     for (i = 0; i < (hfp_ag_indicators_nr-1); i++) {
383         offset += snprintf(buffer+offset, buffer_size-offset, "%d,", hfp_ag_indicators[i].status);
384     }
385     if (i<hfp_ag_indicators_nr){
386         offset += snprintf(buffer+offset, buffer_size-offset, "%d", hfp_ag_indicators[i].status);
387     }
388     return offset;
389 }
390 
391 static int hfp_ag_call_services_join(char * buffer, int buffer_size){
392     if (buffer_size < (hfp_ag_call_hold_services_nr * 3)) return 0;
393     int i;
394     int offset = snprintf(buffer, buffer_size, "(");
395     for (i = 0; i < (hfp_ag_call_hold_services_nr-1); i++) {
396         offset += snprintf(buffer+offset, buffer_size-offset, "%s,", hfp_ag_call_hold_services[i]);
397     }
398     if (i<hfp_ag_call_hold_services_nr){
399         offset += snprintf(buffer+offset, buffer_size-offset, "%s)", hfp_ag_call_hold_services[i]);
400     }
401     return offset;
402 }
403 
404 static int hfp_ag_send_cmd_via_generator(uint16_t cid, hfp_connection_t * hfp_connection,
405     int start_segment, int num_segments,
406     int (*get_segment_len)(hfp_connection_t * hfp_connection, int segment),
407     void (*store_segment) (hfp_connection_t * hfp_connection, int segment, uint8_t * buffer, uint16_t buffer_size)){
408 
409     // assumes: can send now == true
410     // assumes: num segments > 0
411     // assumes: individual segments are smaller than MTU
412     rfcomm_reserve_packet_buffer();
413     int mtu = rfcomm_get_max_frame_size(cid);
414     uint8_t * data = rfcomm_get_outgoing_buffer();
415     int offset = 0;
416     int segment = start_segment;
417     while (segment < num_segments){
418         int segment_len = get_segment_len(hfp_connection, segment);
419         if ((offset + segment_len + 1) > mtu) break;
420         // append segment. As it appends a '\0', we provide a buffer one byte larger
421         store_segment(hfp_connection, segment, data+offset, segment_len + 1);
422         offset += segment_len;
423         segment++;
424     }
425     rfcomm_send_prepared(cid, offset);
426 #ifdef ENABLE_HFP_AT_MESSAGES
427     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_SENT, (char *) data);
428 #endif
429     return segment;
430 }
431 
432 // returns next segment to store
433 static int hfp_ag_send_retrieve_indicators_cmd_via_generator(uint16_t cid, hfp_connection_t * hfp_connection, int start_segment){
434     int num_segments = hfp_ag_indicators_cmd_generator_num_segments(hfp_connection);
435     return hfp_ag_send_cmd_via_generator(cid, hfp_connection, start_segment, num_segments,
436                                          hfp_ag_indicators_cmd_generator_get_segment_len,
437                                          hfp_ag_indicators_cmd_generator_store_segment);
438 }
439 
440 static int hfp_ag_send_retrieve_indicators_status_cmd(uint16_t cid){
441     char buffer[40];
442     const int size = sizeof(buffer);
443     int offset = snprintf(buffer, size, "\r\n%s:", HFP_INDICATOR);
444     offset += hfp_ag_indicators_status_join(buffer+offset, size-offset-9);
445     offset += snprintf(buffer+offset, size-offset, "\r\n\r\nOK\r\n");
446     return send_str_over_rfcomm(cid, buffer);
447 }
448 
449 static int hfp_ag_send_retrieve_can_hold_call_cmd(uint16_t cid){
450     char buffer[40];
451     const int size = sizeof(buffer);
452     int offset = snprintf(buffer, size, "\r\n%s:", HFP_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES);
453     offset += hfp_ag_call_services_join(buffer+offset, size-offset-9);
454     offset += snprintf(buffer+offset, size-offset, "\r\n\r\nOK\r\n");
455     return send_str_over_rfcomm(cid, buffer);
456 }
457 
458 
459 static int hfp_ag_send_list_supported_generic_status_indicators_cmd(uint16_t cid){
460     return hfp_ag_send_ok(cid);
461 }
462 
463 static int hfp_ag_send_retrieve_supported_generic_status_indicators_cmd(uint16_t cid){
464     char buffer[40];
465     const int size = sizeof(buffer);
466     int offset = snprintf(buffer, size, "\r\n%s:(", HFP_GENERIC_STATUS_INDICATOR);
467     offset += hfp_ag_generic_indicators_join(buffer + offset, size - offset - 10);
468     offset += snprintf(buffer+offset, size-offset, ")\r\n\r\nOK\r\n");
469     return send_str_over_rfcomm(cid, buffer);
470 }
471 
472 static int hfp_ag_send_retrieve_initital_supported_generic_status_indicators_cmd(uint16_t cid){
473     char buffer[40];
474     int offset = hfp_ag_generic_indicators_initial_status_join(buffer, sizeof(buffer) - 7);
475     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\nOK\r\n");
476     return send_str_over_rfcomm(cid, buffer);
477 }
478 
479 static int hfp_ag_send_transfer_ag_indicators_status_cmd(uint16_t cid, hfp_ag_indicator_t * indicator){
480     char buffer[20];
481     snprintf(buffer, sizeof(buffer), "\r\n%s:%d,%d\r\n",
482              HFP_TRANSFER_AG_INDICATOR_STATUS, indicator->index,
483              indicator->status);
484     buffer[sizeof(buffer) - 1] = 0;
485     return send_str_over_rfcomm(cid, buffer);
486 }
487 
488 static int hfp_ag_send_report_network_operator_name_cmd(uint16_t cid, hfp_network_opearator_t op){
489     char buffer[41];
490     if (strlen(op.name) == 0){
491         snprintf(buffer, sizeof(buffer), "\r\n%s:%d,,\r\n\r\nOK\r\n", HFP_QUERY_OPERATOR_SELECTION, op.mode);
492     } else {
493         int offset = snprintf(buffer,  sizeof(buffer), "\r\n%s:%d,%d,", HFP_QUERY_OPERATOR_SELECTION, op.mode, op.format);
494         offset += snprintf(buffer+offset, 16, "%s", op.name);
495         snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n\r\nOK\r\n");
496     }
497     return send_str_over_rfcomm(cid, buffer);
498 }
499 
500 static inline int hfp_ag_send_cmd_with_space_and_int(uint16_t cid, const char * cmd, uint8_t value){
501     char buffer[30];
502     snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n", cmd, value);
503     return send_str_over_rfcomm(cid, buffer);
504 }
505 
506 
507 static inline int hfp_ag_send_cmd_with_int(uint16_t cid, const char * cmd, uint8_t value){
508     char buffer[30];
509     snprintf(buffer, sizeof(buffer), "\r\n%s:%d\r\n", cmd, value);
510     return send_str_over_rfcomm(cid, buffer);
511 }
512 
513 static int hfp_ag_send_suggest_codec_cmd(uint16_t cid, uint8_t codec){
514     return hfp_ag_send_cmd_with_int(cid, HFP_CONFIRM_COMMON_CODEC, codec);
515 }
516 
517 static int hfp_ag_send_set_speaker_gain_cmd(uint16_t cid, uint8_t gain){
518     return hfp_ag_send_cmd_with_int(cid, HFP_SET_SPEAKER_GAIN, gain);
519 }
520 
521 static int hfp_ag_send_set_microphone_gain_cmd(uint16_t cid, uint8_t gain){
522     return hfp_ag_send_cmd_with_int(cid, HFP_SET_MICROPHONE_GAIN, gain);
523 }
524 
525 static int hfp_ag_send_set_response_and_hold(uint16_t cid, int state){
526     return hfp_ag_send_cmd_with_space_and_int(cid, HFP_RESPONSE_AND_HOLD, state);
527 }
528 
529 static int hfp_ag_send_enhanced_voice_recognition_state_cmd(hfp_connection_t * hfp_connection){
530     char buffer[30];
531     uint8_t evra_enabled = hfp_connection->enhanced_voice_recognition_enabled ? 1 : 0;
532     snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, evra_enabled, hfp_connection->ag_vra_state);
533     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
534 }
535 
536 static int hfp_ag_send_voice_recognition_cmd(hfp_connection_t * hfp_connection, uint8_t activate_voice_recognition){
537     char buffer[30];
538     if (hfp_connection->enhanced_voice_recognition_enabled){
539         snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, activate_voice_recognition, hfp_connection->ag_vra_state);
540     } else {
541         snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, activate_voice_recognition);
542     }
543     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
544 }
545 
546 static int hfp_ag_send_enhanced_voice_recognition_msg_cmd(hfp_connection_t * hfp_connection){
547     char buffer[HFP_VR_TEXT_HEADER_SIZE + HFP_MAX_VR_TEXT_SIZE];
548     snprintf(buffer, sizeof(buffer), "\r\n%s: 1,%d,%X,%d,%d,\"%s\"\r\n", HFP_ACTIVATE_VOICE_RECOGNITION,
549         hfp_connection->ag_vra_state,
550         hfp_connection->ag_msg.text_id,
551         hfp_connection->ag_msg.text_type,
552         hfp_connection->ag_msg.text_operation,
553         hfp_connection->ag_msg.text);
554     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
555 }
556 
557 static uint8_t hfp_ag_suggest_codec(hfp_connection_t *hfp_connection){
558     if (hfp_connection->sco_for_msbc_failed) return HFP_CODEC_CVSD;
559 
560 #ifdef ENABLE_HFP_SUPER_WIDE_BAND_SPEECH
561     if (hfp_supports_codec(HFP_CODEC_LC3_SWB, hfp_ag_codecs_nr, hfp_ag_codecs)){
562         if (hfp_supports_codec(HFP_CODEC_LC3_SWB, hfp_connection->remote_codecs_nr, hfp_connection->remote_codecs)){
563             return HFP_CODEC_LC3_SWB;
564         }
565     }
566 #endif
567 
568 #ifdef ENABLE_HFP_WIDE_BAND_SPEECH
569     if (hfp_supports_codec(HFP_CODEC_MSBC, hfp_ag_codecs_nr, hfp_ag_codecs)){
570         if (hfp_supports_codec(HFP_CODEC_MSBC, hfp_connection->remote_codecs_nr, hfp_connection->remote_codecs)){
571             return HFP_CODEC_MSBC;
572         }
573     }
574 #endif
575 
576     return HFP_CODEC_CVSD;
577 }
578 
579 /* state machines */
580 
581 static uint8_t hfp_ag_esco_s4_supported(hfp_connection_t * hfp_connection){
582     return (hfp_connection->remote_supported_features & (1<<HFP_HFSF_ESCO_S4)) &&  (hfp_ag_supported_features & (1 << HFP_AGSF_ESCO_S4));
583 }
584 
585 static int codecs_exchange_state_machine(hfp_connection_t * hfp_connection){
586     /* events ( == commands):
587         HFP_CMD_AVAILABLE_CODECS == received AT+BAC with list of codecs
588         HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP:
589             hf_trigger_codec_connection_setup == received BCC
590             ag_trigger_codec_connection_setup == received from AG to send BCS
591         HFP_CMD_HF_CONFIRMED_CODEC == received AT+BCS
592     */
593     switch (hfp_connection->codecs_state){
594         case HFP_CODECS_EXCHANGED:
595             if (hfp_connection->command == HFP_CMD_AVAILABLE_CODECS){
596                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
597                 return 1;
598             }
599             break;
600 
601         case HFP_CODECS_RECEIVED_TRIGGER_CODEC_EXCHANGE:
602         case HFP_CODECS_AG_RESEND_COMMON_CODEC:
603             hfp_connection->ag_send_common_codec = true;
604             break;
605         default:
606             break;
607     }
608 
609     if (hfp_connection->ag_send_common_codec){
610         hfp_connection->ag_send_common_codec = false;
611         hfp_connection->codecs_state = HFP_CODECS_AG_SENT_COMMON_CODEC;
612         hfp_connection->suggested_codec = hfp_ag_suggest_codec(hfp_connection);
613         hfp_ag_send_suggest_codec_cmd(hfp_connection->rfcomm_cid, hfp_connection->suggested_codec);
614         return 1;
615     }
616 
617     switch (hfp_connection->command){
618         case HFP_CMD_AVAILABLE_CODECS:
619             if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED){
620                 hfp_connection->codecs_state = HFP_CODECS_RECEIVED_LIST;
621                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
622                 return 1;
623             }
624 
625             switch (hfp_connection->codecs_state){
626                 case HFP_CODECS_AG_SENT_COMMON_CODEC:
627                     hfp_connection->codecs_state = HFP_CODECS_AG_RESEND_COMMON_CODEC;
628                     break;
629                 default:
630                     break;
631             }
632             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
633             return 1;
634 
635         case HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP:
636             hfp_connection->codecs_state = HFP_CODECS_RECEIVED_TRIGGER_CODEC_EXCHANGE;
637             hfp_connection->establish_audio_connection = 1;
638             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
639             return 1;
640 
641         case HFP_CMD_HF_CONFIRMED_CODEC:
642             if (hfp_connection->codec_confirmed != hfp_connection->suggested_codec){
643                 hfp_connection->codecs_state = HFP_CODECS_ERROR;
644                 hfp_ag_send_error(hfp_connection->rfcomm_cid);
645                 return 1;
646             }
647             hfp_connection->negotiated_codec = hfp_connection->codec_confirmed;
648             hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
649             log_info("hfp: codec confirmed: %s", (hfp_connection->negotiated_codec == HFP_CODEC_MSBC) ? "mSBC" : "CVSD");
650             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
651             // now, pick link settings
652             hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
653             // configure SBC coded if needed
654             hfp_prepare_for_sco(hfp_connection);
655             return 1;
656         default:
657             break;
658     }
659     return 0;
660 }
661 
662 static void hfp_ag_slc_established(hfp_connection_t * hfp_connection){
663     hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
664     hfp_emit_slc_connection_event(hfp_connection->local_role, 0, hfp_connection->acl_handle, hfp_connection->remote_addr);
665 
666     // in-band ring tone is active if supported
667     hfp_connection->ag_in_band_ring_tone_active = has_in_band_ring_tone();
668 
669     // HFP 4.35: "When [...] a new Service Level Connection is established all indicators are activated by default."
670     uint16_t i;
671     for (i=0;i<hfp_connection->ag_indicators_nr;i++){
672         hfp_connection->ag_indicators[i].enabled = 1;
673     }
674 
675     // if active call exist, set per-hfp_connection state active, too (when audio is on)
676     if (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT){
677         hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
678     }
679     // if AG is ringing, also start ringing on the HF
680     if (hfp_gsm_call_status() == HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS){
681         switch (hfp_gsm_callsetup_status()){
682             case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
683                 hfp_ag_hf_start_ringing_incoming(hfp_connection);
684                 break;
685             case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
686                 hfp_ag_hf_start_ringing_outgoing(hfp_connection);
687                 break;
688             default:
689                 break;
690         }
691     }
692 }
693 
694 static int hfp_ag_run_for_context_service_level_connection(hfp_connection_t * hfp_connection){
695     // log_info("hfp_ag_run_for_context_service_level_connection state %u, command %u", hfp_connection->state, hfp_connection->command);
696     if (hfp_connection->state >= HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) return 0;
697     int sent = 0;
698     switch(hfp_connection->command){
699         case HFP_CMD_SUPPORTED_FEATURES:
700             switch(hfp_connection->state){
701                 case HFP_W4_EXCHANGE_SUPPORTED_FEATURES:
702                 case HFP_EXCHANGE_SUPPORTED_FEATURES:
703                     hfp_hf_drop_mSBC_if_eSCO_not_supported(hfp_ag_codecs, &hfp_ag_codecs_nr);
704                     if (has_codec_negotiation_feature(hfp_connection)){
705                         hfp_connection->state = HFP_W4_NOTIFY_ON_CODECS;
706                     } else {
707                         hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS;
708                     }
709                     hfp_ag_exchange_supported_features_cmd(hfp_connection->rfcomm_cid);
710                     return 1;
711                 default:
712                     break;
713             }
714             break;
715         case HFP_CMD_AVAILABLE_CODECS:
716             sent = codecs_exchange_state_machine(hfp_connection);
717             if (hfp_connection->codecs_state == HFP_CODECS_RECEIVED_LIST){
718                 hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS;
719             }
720             return sent;
721 
722         case HFP_CMD_RETRIEVE_AG_INDICATORS:
723             if (hfp_connection->state == HFP_W4_RETRIEVE_INDICATORS) {
724                 // HF requested AG Indicators and we did expect it
725                 hfp_connection->send_ag_indicators_segment = 0;
726                 hfp_connection->state = HFP_RETRIEVE_INDICATORS;
727                 // continue below in state switch
728             }
729             break;
730 
731         case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
732             if (hfp_connection->state != HFP_W4_RETRIEVE_INDICATORS_STATUS) break;
733             hfp_connection->state = HFP_W4_ENABLE_INDICATORS_STATUS_UPDATE;
734             hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
735             return 1;
736 
737         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
738             if (hfp_connection->state != HFP_W4_ENABLE_INDICATORS_STATUS_UPDATE) break;
739             if (has_call_waiting_and_3way_calling_feature(hfp_connection)){
740                 hfp_connection->state = HFP_W4_RETRIEVE_CAN_HOLD_CALL;
741             } else if (has_hf_indicators_feature(hfp_connection)){
742                 hfp_connection->state = HFP_W4_LIST_GENERIC_STATUS_INDICATORS;
743             } else {
744                 hfp_ag_slc_established(hfp_connection);
745             }
746             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
747             return 1;
748 
749         case HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES:
750             if (hfp_connection->state != HFP_W4_RETRIEVE_CAN_HOLD_CALL) break;
751             if (has_hf_indicators_feature(hfp_connection)){
752                 hfp_connection->state = HFP_W4_LIST_GENERIC_STATUS_INDICATORS;
753             }
754             hfp_ag_send_retrieve_can_hold_call_cmd(hfp_connection->rfcomm_cid);
755             if (!has_hf_indicators_feature(hfp_connection)){
756                 hfp_ag_slc_established(hfp_connection);
757             }
758             return 1;
759 
760         case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
761             if (hfp_connection->state != HFP_W4_LIST_GENERIC_STATUS_INDICATORS) break;
762             hfp_connection->state = HFP_W4_RETRIEVE_GENERIC_STATUS_INDICATORS;
763             hfp_ag_send_list_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
764             return 1;
765 
766         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
767             if (hfp_connection->state != HFP_W4_RETRIEVE_GENERIC_STATUS_INDICATORS) break;
768             hfp_connection->state = HFP_W4_RETRIEVE_INITITAL_STATE_GENERIC_STATUS_INDICATORS;
769             hfp_ag_send_retrieve_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
770             return 1;
771 
772         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
773             if (hfp_connection->state != HFP_W4_RETRIEVE_INITITAL_STATE_GENERIC_STATUS_INDICATORS) break;
774             hfp_ag_send_retrieve_initital_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
775             hfp_ag_slc_established(hfp_connection);
776             return 1;
777         default:
778             break;
779     }
780 
781     switch (hfp_connection->state){
782         case HFP_RETRIEVE_INDICATORS: {
783             int next_segment = hfp_ag_send_retrieve_indicators_cmd_via_generator(hfp_connection->rfcomm_cid, hfp_connection, hfp_connection->send_ag_indicators_segment);
784             int num_segments = hfp_ag_indicators_cmd_generator_num_segments(hfp_connection);
785             log_info("HFP_CMD_RETRIEVE_AG_INDICATORS next segment %u, num_segments %u", next_segment, num_segments);
786             if (next_segment < num_segments){
787                 // prepare sending of next segment
788                 hfp_connection->send_ag_indicators_segment = next_segment;
789                 log_info("HFP_CMD_RETRIEVE_AG_INDICATORS more. command %u, next seg %u", hfp_connection->command, next_segment);
790             } else {
791                 // done, go to next state
792                 hfp_connection->send_ag_indicators_segment = 0;
793                 hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS_STATUS;
794             }
795             return 1;
796         }
797         default:
798             break;
799     }
800     return 0;
801 }
802 
803 static bool hfp_ag_vra_flag_supported(hfp_connection_t * hfp_connection){
804     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_VOICE_RECOGNITION_FUNCTION);
805     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_VOICE_RECOGNITION_FUNCTION);
806     return hf && ag;
807 }
808 
809 static bool hfp_ag_enhanced_vra_flag_supported(hfp_connection_t * hfp_connection){
810     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS);
811     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_ENHANCED_VOICE_RECOGNITION_STATUS);
812     return hf && ag;
813 }
814 
815 static bool hfp_ag_can_send_enhanced_vra_message_flag_supported(hfp_connection_t * hfp_connection){
816     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_VOICE_RECOGNITION_TEXT);
817     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_VOICE_RECOGNITION_TEXT);
818     return hf && ag;
819 }
820 
821 static bool hfp_ag_can_activate_voice_recognition(hfp_connection_t * hfp_connection){
822     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED || hfp_connection->state > HFP_AUDIO_CONNECTION_ESTABLISHED){
823         return false;
824     }
825     if (hfp_connection->vra_state != HFP_VRA_VOICE_RECOGNITION_OFF){
826         return false;
827     }
828     if (hfp_connection->ag_vra_send_command){
829         return false;
830     }
831     return true;
832 }
833 
834 static bool hfp_ag_voice_recognition_session_active(hfp_connection_t * hfp_connection){
835     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED || hfp_connection->state > HFP_AUDIO_CONNECTION_ESTABLISHED){
836         return false;
837     }
838     if (hfp_connection->vra_state != HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
839         if (hfp_connection->vra_state == HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
840             return true;
841         }
842         return false;
843     }
844     return true;
845 }
846 
847 static bool hfp_ag_is_audio_connection_active(hfp_connection_t * hfp_connection){
848     switch (hfp_connection->state){
849         case HFP_W2_CONNECT_SCO:
850         case HFP_W4_SCO_CONNECTED:
851         case HFP_AUDIO_CONNECTION_ESTABLISHED:
852             return true;
853         default:
854             return false;
855     }
856 }
857 
858 static void hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection_t * hfp_connection, uint8_t status){
859     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
860 
861     uint8_t event[6];
862     event[0] = HCI_EVENT_HFP_META;
863     event[1] = sizeof(event) - 2;
864     event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_AG_MESSAGE_SENT;
865     little_endian_store_16(event, 3, acl_handle);
866     event[5] = status;
867     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
868 }
869 
870 
871 static void hfp_ag_emit_hf_indicator_value(hfp_connection_t * hfp_connection, uint16_t uuid, uint8_t value){
872     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
873 
874     uint8_t event[8];
875     event[0] = HCI_EVENT_HFP_META;
876     event[1] = sizeof(event) - 2;
877     event[2] = HFP_SUBEVENT_HF_INDICATOR;
878     little_endian_store_16(event, 3, acl_handle);
879     little_endian_store_16(event, 5, uuid);
880     event[7] = value;
881     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
882 }
883 
884 static void hfp_ag_emit_general_simple_event(uint8_t event_subtype){
885     if (!hfp_ag_callback) return;
886 
887     uint8_t event[5];
888     event[0] = HCI_EVENT_HFP_META;
889     event[1] = sizeof(event) - 2;
890     event[2] = event_subtype;
891     little_endian_store_16(event, 3, HCI_CON_HANDLE_INVALID);
892     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
893 }
894 
895 static void hfp_ag_emit_custom_command_event(hfp_connection_t * hfp_connection){
896     btstack_assert(sizeof(hfp_connection->line_buffer) < (255-5));
897 
898     uint16_t line_len = strlen((const char*)hfp_connection->line_buffer) + 1;
899     uint8_t event[7 + sizeof(hfp_connection->line_buffer)];
900     event[0] = HCI_EVENT_HFP_META;
901     event[1] = 5 + line_len;
902     event[2] = HFP_SUBEVENT_CUSTOM_AT_COMMAND;
903     little_endian_store_16(event, 3, hfp_connection->acl_handle);
904     little_endian_store_16(event, 5, hfp_connection->custom_at_command_id);
905     memcpy(&event[7], hfp_connection->line_buffer, line_len);
906     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, 7 + line_len);
907 }
908 
909 // @return status
910 static uint8_t hfp_ag_vra_state_machine_two(hfp_connection_t * hfp_connection){
911     uint8_t status = ERROR_CODE_SUCCESS;
912     switch (hfp_connection->vra_state_requested){
913         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO:
914             if (!hfp_ag_is_audio_connection_active(hfp_connection)){
915                 status = hfp_ag_setup_audio_connection(hfp_connection);
916                 if (status != ERROR_CODE_SUCCESS){
917                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
918                     hfp_emit_voice_recognition_enabled(hfp_connection, status);
919                     break;
920                 }
921             }
922             hfp_connection->enhanced_voice_recognition_enabled = true;
923             hfp_connection->vra_state = HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO;
924             hfp_connection->vra_state_requested = hfp_connection->vra_state;
925             hfp_emit_enhanced_voice_recognition_hf_ready_for_audio_event(hfp_connection, ERROR_CODE_SUCCESS);
926             break;
927 
928         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF:
929             hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_OFF;
930             hfp_connection->vra_state_requested = hfp_connection->vra_state;
931 
932             // release audio connection only if it was opened after audio VR activated
933             if (hfp_ag_is_audio_connection_active(hfp_connection) && !hfp_connection->ag_audio_connection_opened_before_vra){
934                 hfp_trigger_release_audio_connection(hfp_connection);
935             }
936 
937             hfp_emit_voice_recognition_disabled(hfp_connection, ERROR_CODE_SUCCESS);
938             break;
939 
940         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED:
941             // open only if audio connection does not already exist
942             if (!hfp_ag_is_audio_connection_active(hfp_connection)){
943                 status = hfp_ag_setup_audio_connection(hfp_connection);
944                 if (status != ERROR_CODE_SUCCESS){
945                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
946                     hfp_emit_voice_recognition_enabled(hfp_connection, status);
947                     break;
948                 }
949             }
950 
951             hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_ACTIVATED;
952             hfp_connection->vra_state_requested = hfp_connection->vra_state;
953             hfp_connection->enhanced_voice_recognition_enabled = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
954 
955             if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
956                 hfp_emit_voice_recognition_enabled(hfp_connection, ERROR_CODE_SUCCESS);
957             } else {
958                 hfp_connection->emit_vra_enabled_after_audio_established = true;
959             }
960             break;
961 
962         default:
963             break;
964     }
965     return status;
966 }
967 
968 static uint8_t hfp_ag_vra_send_command(hfp_connection_t * hfp_connection){
969     uint8_t done = 0;
970     uint8_t status;
971 
972     switch (hfp_connection->vra_state_requested){
973         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG:
974             done = hfp_ag_send_enhanced_voice_recognition_msg_cmd(hfp_connection);
975             if (done == 0){
976                 hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection, ERROR_CODE_UNSPECIFIED_ERROR);
977             } else {
978                 hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection, ERROR_CODE_SUCCESS);
979             }
980             hfp_connection->vra_state_requested = hfp_connection->vra_state;
981             return done;
982 
983         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS:
984             done = hfp_ag_send_enhanced_voice_recognition_state_cmd(hfp_connection);
985             if (done == 0){
986                 hfp_emit_enhanced_voice_recognition_state_event(hfp_connection, ERROR_CODE_UNSPECIFIED_ERROR);
987             } else {
988                 hfp_emit_enhanced_voice_recognition_state_event(hfp_connection, ERROR_CODE_SUCCESS);
989             }
990             hfp_connection->vra_state_requested = hfp_connection->vra_state;
991             return done;
992 
993         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED:
994         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF:
995             done = hfp_ag_send_voice_recognition_cmd(hfp_connection, hfp_connection->ag_activate_voice_recognition_value);
996             if (done == 0){
997                 hfp_connection->vra_state_requested = hfp_connection->vra_state;
998 
999                 if (hfp_connection->ag_activate_voice_recognition_value == 1){
1000                     hfp_emit_voice_recognition_enabled(hfp_connection, done);
1001                 } else {
1002                     hfp_emit_voice_recognition_disabled(hfp_connection, done);
1003                 }
1004                 return 0;
1005             }
1006             status = hfp_ag_vra_state_machine_two(hfp_connection);
1007             return (status == ERROR_CODE_SUCCESS) ? 1 : 0;
1008 
1009         default:
1010             log_error("state %u", hfp_connection->vra_state_requested);
1011             btstack_assert(false);
1012             return 0;
1013     }
1014 }
1015 
1016 static int hfp_ag_voice_recognition_state_machine(hfp_connection_t * hfp_connection){
1017     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) {
1018         return 0;
1019     }
1020     int done = 0;
1021     uint8_t status;
1022 
1023     // VRA action initiated by AG
1024     if (hfp_connection->ag_vra_send_command){
1025         hfp_connection->ag_vra_send_command = false;
1026         return hfp_ag_vra_send_command(hfp_connection);
1027     }
1028 
1029     if (hfp_connection->ag_vra_requested_by_hf){
1030         hfp_connection->ag_vra_requested_by_hf = false;
1031 
1032         // HF initiatied voice recognition, parser extracted activation value
1033         switch (hfp_connection->ag_activate_voice_recognition_value){
1034             case 0:
1035                 if (hfp_ag_voice_recognition_session_active(hfp_connection)){
1036                     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
1037                     done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1038                 }
1039                 break;
1040 
1041                 case 1:
1042                     if (hfp_ag_can_activate_voice_recognition(hfp_connection)){
1043                         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
1044                         done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1045                     }
1046                     break;
1047 
1048                     case 2:
1049                         if (hfp_ag_voice_recognition_session_active(hfp_connection)){
1050                             hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO;
1051                             done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1052                         }
1053                         break;
1054                         default:
1055                             break;
1056         }
1057         if (done == 0){
1058             hfp_connection->vra_state_requested = hfp_connection->vra_state;
1059             done = hfp_ag_send_error(hfp_connection->rfcomm_cid);
1060             return 1;
1061         }
1062 
1063         status = hfp_ag_vra_state_machine_two(hfp_connection);
1064         return (status == ERROR_CODE_SUCCESS) ? 1 : 0;
1065     }
1066 
1067     return 0;
1068 }
1069 
1070 static int hfp_ag_run_for_context_service_level_connection_queries(hfp_connection_t * hfp_connection){
1071     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) {
1072         return 0;
1073     }
1074 
1075     int sent = codecs_exchange_state_machine(hfp_connection);
1076     if (sent) return 1;
1077 
1078     if (has_in_band_ring_tone()){
1079         if (hfp_connection->ag_in_band_ring_tone_active != hfp_ag_in_band_ring_tone_active) {
1080             hfp_connection->ag_in_band_ring_tone_active = hfp_ag_in_band_ring_tone_active;
1081             hfp_ag_send_change_in_band_ring_tone_setting_cmd(hfp_connection);
1082             return 1;
1083         }
1084     }
1085 
1086     switch(hfp_connection->command){
1087         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1088             hfp_ag_send_report_network_operator_name_cmd(hfp_connection->rfcomm_cid, hfp_connection->network_operator);
1089             return 1;
1090         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1091             if (hfp_connection->network_operator.format != 0){
1092                 hfp_ag_send_error(hfp_connection->rfcomm_cid);
1093             } else {
1094                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1095             }
1096             return 1;
1097         case HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE:
1098             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1099             return 1;
1100         case HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR:
1101             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1102             return 1;
1103         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
1104             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1105             return 1;
1106         default:
1107             break;
1108     }
1109     return 0;
1110 }
1111 
1112 static int hfp_ag_run_for_audio_connection(hfp_connection_t * hfp_connection){
1113     if ((hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) ||
1114         (hfp_connection->state > HFP_W2_DISCONNECT_SCO)) return 0;
1115 
1116     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1117 
1118     if (hfp_connection->release_audio_connection){
1119         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
1120         hfp_connection->release_audio_connection = 0;
1121         gap_disconnect(hfp_connection->sco_handle);
1122         return 1;
1123     }
1124 
1125     // accept incoming audio connection (codec negotiation is not used)
1126     if (hfp_connection->accept_sco && (hfp_sco_setup_active() == false)){
1127         // notify about codec selection if not done already
1128         if (hfp_connection->negotiated_codec == 0){
1129             hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
1130         }
1131         //
1132         bool incoming_eSCO = hfp_connection->accept_sco == 2;
1133         hfp_connection->state = HFP_W4_SCO_CONNECTED;
1134         hfp_accept_synchronous_connection(hfp_connection, incoming_eSCO);
1135         return 1;
1136     }
1137 
1138     // run codecs exchange
1139     int sent = codecs_exchange_state_machine(hfp_connection);
1140     if (sent) return 1;
1141 
1142     if (hfp_connection->codecs_state != HFP_CODECS_EXCHANGED) return 0;
1143     if (hfp_sco_setup_active()) return 0;
1144     if (hci_can_send_command_packet_now() == false) return 0;
1145     if (hfp_connection->establish_audio_connection){
1146         hfp_connection->state = HFP_W4_SCO_CONNECTED;
1147         hfp_connection->establish_audio_connection = 0;
1148         hfp_setup_synchronous_connection(hfp_connection);
1149         return 1;
1150     }
1151     return 0;
1152 }
1153 
1154 static void hfp_ag_set_callsetup_indicator(void){
1155     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("callsetup");
1156     if (!indicator){
1157         log_error("hfp_ag_set_callsetup_indicator: callsetup indicator is missing");
1158         return;
1159     };
1160     indicator->status = hfp_gsm_callsetup_status();
1161 }
1162 
1163 static void hfp_ag_set_callheld_indicator(void){
1164     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("callheld");
1165     if (!indicator){
1166         log_error("hfp_ag_set_callheld_state: callheld indicator is missing");
1167         return;
1168     };
1169     indicator->status = hfp_gsm_callheld_status();
1170 }
1171 
1172 //
1173 // transition implementations for hfp_ag_call_state_machine
1174 //
1175 
1176 static void hfp_ag_hf_start_ringing_incoming(hfp_connection_t * hfp_connection){
1177     if (use_in_band_tone(hfp_connection)){
1178         hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING;
1179         hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1180     } else {
1181         hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1182     }
1183 }
1184 
1185 static void hfp_ag_hf_start_ringing_outgoing(hfp_connection_t * hfp_connection){
1186     hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1187 }
1188 
1189 static void hfp_ag_hf_stop_ringing(hfp_connection_t * hfp_connection){
1190     hfp_connection->ag_ring = 0;
1191     hfp_connection->ag_send_clip = 0;
1192 }
1193 
1194 
1195 static void hfp_ag_trigger_incoming_call_during_active_one(void){
1196     btstack_linked_list_iterator_t it;
1197     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1198     while (btstack_linked_list_iterator_has_next(&it)){
1199         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1200         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1201         if (hfp_connection->call_state != HFP_CALL_ACTIVE) continue;
1202 
1203         hfp_connection->call_state = HFP_CALL_W2_SEND_CALL_WAITING;
1204         hfp_ag_run_for_context(hfp_connection);
1205     }
1206 }
1207 
1208 static void hfp_ag_trigger_ring_and_clip(void) {
1209     btstack_linked_list_iterator_t it;
1210     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1211     while (btstack_linked_list_iterator_has_next(&it)){
1212         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1213         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1214         switch (hfp_connection->call_state){
1215             case HFP_CALL_INCOMING_RINGING:
1216             case HFP_CALL_OUTGOING_RINGING:
1217             case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1218                 // Queue RING on this connection
1219                 hfp_connection->ag_ring = 1;
1220 
1221                 // HFP v1.8, 4.23 Calling Line Identification (CLI) Notification
1222                 // "If the calling subscriber number information is available from the network, the AG shall issue the
1223                 // +CLIP unsolicited result code just after every RING indication when the HF is alerted in an incoming call."
1224                 hfp_connection->ag_send_clip = hfp_gsm_clip_type() && hfp_connection->clip_enabled;
1225 
1226                 // trigger next message
1227                 rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1228                 break;
1229             default:
1230                 break;
1231         }
1232     }
1233 }
1234 
1235 // trigger RING and CLIP messages on connections that are ringing
1236 static void hfp_ag_ring_timeout_handler(btstack_timer_source_t * timer){
1237     hfp_ag_trigger_ring_and_clip();
1238 
1239     btstack_run_loop_set_timer(timer, HFP_RING_PERIOD_MS); // 2 seconds timeout
1240     btstack_run_loop_add_timer(timer);
1241 }
1242 
1243 static void hfp_ag_ring_timeout_stop(void){
1244     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1245 }
1246 
1247 static void hfp_ag_start_ringing(void){
1248     // setup ring timer
1249     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1250     btstack_run_loop_set_timer_handler(&hfp_ag_ring_timeout, hfp_ag_ring_timeout_handler);
1251     btstack_run_loop_set_timer(&hfp_ag_ring_timeout, HFP_RING_PERIOD_MS); // 2 seconds timeout
1252     btstack_run_loop_add_timer(&hfp_ag_ring_timeout);
1253 
1254     // emit start ringing
1255     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_START_RINGING);
1256 
1257     // send initial RING + CLIP
1258     hfp_ag_trigger_ring_and_clip();
1259 }
1260 
1261 static void hfp_ag_stop_ringing(void){
1262     hfp_ag_ring_timeout_stop();
1263     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_STOP_RINGING);
1264 
1265     btstack_linked_list_iterator_t it;
1266     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1267     while (btstack_linked_list_iterator_has_next(&it)){
1268         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1269         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1270         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1271             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1272         hfp_ag_hf_stop_ringing(hfp_connection);
1273     }
1274 }
1275 
1276 static void hfp_ag_trigger_incoming_call_idle(void){
1277     int indicator_index = get_ag_indicator_index_for_name("callsetup");
1278     if (indicator_index < 0) return;
1279 
1280     // update callsetup state in connections
1281     btstack_linked_list_iterator_t it;
1282     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1283     while (btstack_linked_list_iterator_has_next(&it)){
1284         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1285         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1286         if (hfp_connection->call_state != HFP_CALL_IDLE) continue;
1287 
1288         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1289 
1290         hfp_ag_hf_start_ringing_incoming(hfp_connection);
1291 
1292         hfp_ag_run_for_context(hfp_connection);
1293     }
1294 
1295     // start local ringing - started after connection state has been updated
1296     hfp_ag_start_ringing();
1297 }
1298 
1299 static void hfp_ag_trigger_outgoing_call(void){
1300     btstack_linked_list_iterator_t it;
1301     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1302     while (btstack_linked_list_iterator_has_next(&it)){
1303         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1304         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1305         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1306         if (hfp_connection->call_state == HFP_CALL_IDLE){
1307             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1308         }
1309     }
1310 }
1311 
1312 static void hfp_ag_handle_outgoing_call_accepted(hfp_connection_t * hfp_connection){
1313     hfp_connection->call_state = HFP_CALL_OUTGOING_DIALING;
1314 
1315     // trigger callsetup to be
1316     int put_call_on_hold = hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT;
1317     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ACCEPTED, 0, 0, NULL);
1318 
1319     int indicator_index ;
1320 
1321     hfp_ag_set_callsetup_indicator();
1322     indicator_index = get_ag_indicator_index_for_name("callsetup");
1323     hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1324 
1325     // put current call on hold if active
1326     if (put_call_on_hold){
1327         log_info("AG putting current call on hold for new outgoing call");
1328         hfp_ag_set_callheld_indicator();
1329         indicator_index = get_ag_indicator_index_for_name("callheld");
1330         hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[indicator_index]);
1331     }
1332 
1333     // start audio if needed
1334     hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1335 }
1336 
1337 static void hfp_ag_transfer_indicator(const char * name){
1338     int indicator_index = get_ag_indicator_index_for_name(name);
1339     if (indicator_index < 0) return;
1340 
1341     btstack_linked_list_iterator_t it;
1342     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1343     while (btstack_linked_list_iterator_has_next(&it)){
1344         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1345         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1346         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1347         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1348         hfp_ag_run_for_context(hfp_connection);
1349     }
1350 }
1351 
1352 static void hfp_ag_transfer_callsetup_state(void){
1353     hfp_ag_transfer_indicator("callsetup");
1354 }
1355 
1356 static void hfp_ag_transfer_call_state(void){
1357     hfp_ag_transfer_indicator("call");
1358 }
1359 
1360 static void hfp_ag_transfer_callheld_state(void){
1361     hfp_ag_transfer_indicator("callheld");
1362 }
1363 
1364 static void hfp_ag_hf_accept_call(hfp_connection_t * source){
1365     int call_indicator_index = get_ag_indicator_index_for_name("call");
1366     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1367 
1368     hfp_ag_stop_ringing();
1369 
1370     btstack_linked_list_iterator_t it;
1371     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1372     while (btstack_linked_list_iterator_has_next(&it)){
1373         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1374         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1375         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1376             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1377 
1378         if (hfp_connection == source){
1379 
1380             if (use_in_band_tone(hfp_connection)){
1381                 hfp_connection->call_state = HFP_CALL_ACTIVE;
1382             } else {
1383                 hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
1384                 hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1385             }
1386 
1387             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1388             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1389 
1390         } else {
1391             hfp_connection->call_state = HFP_CALL_IDLE;
1392         }
1393         hfp_ag_run_for_context(hfp_connection);
1394     }
1395 }
1396 
1397 static void hfp_ag_ag_accept_call(void){
1398     int call_indicator_index = get_ag_indicator_index_for_name("call");
1399     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1400 
1401     hfp_ag_stop_ringing();
1402 
1403     btstack_linked_list_iterator_t it;
1404     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1405     while (btstack_linked_list_iterator_has_next(&it)){
1406         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1407         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1408         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1409             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1410 
1411         hfp_connection->call_state = HFP_CALL_TRIGGER_AUDIO_CONNECTION;
1412 
1413         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1414         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1415 
1416         hfp_ag_run_for_context(hfp_connection);
1417         break;  // only single
1418     }
1419 }
1420 
1421 static void hfp_ag_trigger_reject_call(void){
1422     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1423 
1424     hfp_ag_stop_ringing();
1425 
1426     btstack_linked_list_iterator_t it;
1427     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1428     while (btstack_linked_list_iterator_has_next(&it)){
1429         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1430         if (connection->local_role != HFP_ROLE_AG) continue;
1431 
1432         switch (connection->call_state){
1433             case HFP_CALL_INCOMING_RINGING:
1434             case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1435             case HFP_CALL_OUTGOING_RINGING:
1436             case HFP_CALL_OUTGOING_INITIATED:
1437             case HFP_CALL_OUTGOING_DIALING:
1438                 break;
1439             default:
1440                 continue;
1441         }
1442 
1443         connection->call_state = HFP_CALL_IDLE;
1444         connection->ag_indicators_status_update_bitmap = store_bit(connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1445 
1446         if (connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1447             connection->release_audio_connection = 1;
1448         }
1449         hfp_emit_simple_event(connection, HFP_SUBEVENT_CALL_TERMINATED);
1450         hfp_ag_run_for_context(connection);
1451         rfcomm_request_can_send_now_event(connection->rfcomm_cid);
1452     }
1453 }
1454 
1455 static void hfp_ag_trigger_terminate_call(void){
1456     int call_indicator_index = get_ag_indicator_index_for_name("call");
1457 
1458     // no ringing during call
1459 
1460     btstack_linked_list_iterator_t it;
1461     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1462     while (btstack_linked_list_iterator_has_next(&it)){
1463         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1464         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1465         if (hfp_connection->call_state == HFP_CALL_IDLE) continue;
1466 
1467         hfp_connection->call_state = HFP_CALL_IDLE;
1468         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1469 
1470         if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1471             hfp_connection->release_audio_connection = 1;
1472         }
1473 
1474         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_TERMINATED);
1475         hfp_ag_run_for_context(hfp_connection);
1476         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1477     }
1478 }
1479 
1480 static void hfp_ag_set_call_indicator(void){
1481     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("call");
1482     if (!indicator){
1483         log_error("hfp_ag_set_call_state: call indicator is missing");
1484         return;
1485     };
1486     indicator->status = hfp_gsm_call_status();
1487 }
1488 
1489 static hfp_connection_t * hfp_ag_connection_for_call_state(hfp_call_state_t call_state){
1490     btstack_linked_list_iterator_t it;
1491     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1492     while (btstack_linked_list_iterator_has_next(&it)){
1493         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1494         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1495         if (hfp_connection->call_state == call_state) return hfp_connection;
1496     }
1497     return NULL;
1498 }
1499 
1500 static void hfp_ag_send_response_and_hold_state(hfp_response_and_hold_state_t state){
1501     btstack_linked_list_iterator_t it;
1502     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1503     while (btstack_linked_list_iterator_has_next(&it)){
1504         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1505         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1506         hfp_connection->send_response_and_hold_status = state + 1;
1507     }
1508 }
1509 
1510 static int call_setup_state_machine(hfp_connection_t * hfp_connection){
1511     int indicator_index;
1512     switch (hfp_connection->call_state){
1513         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1514             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1515             // we got event: audio hfp_connection established
1516             hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1517             break;
1518         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE:
1519             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1520             // we got event: audio hfp_connection established
1521             hfp_connection->call_state = HFP_CALL_ACTIVE;
1522             break;
1523         case HFP_CALL_W2_SEND_CALL_WAITING:
1524             hfp_connection->call_state = HFP_CALL_W4_CHLD;
1525             hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
1526             indicator_index = get_ag_indicator_index_for_name("callsetup");
1527             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1528             break;
1529         default:
1530             break;
1531     }
1532     return 0;
1533 }
1534 
1535 // queue 'error' to HF
1536 static void hfp_ag_queue_error(hfp_connection_t * hfp_connection){
1537     hfp_connection->send_error++;
1538 }
1539 
1540 // queue 'ok' to HF
1541 static void hfp_ag_queue_ok(hfp_connection_t * hfp_connection){
1542     hfp_connection->ok_pending++;
1543 }
1544 
1545 // functions extracted from hfp_ag_call_sm below
1546 static void hfp_ag_handle_reject_outgoing_call(void){
1547     hfp_connection_t * hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1548     if (!hfp_connection){
1549         log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1550         return;
1551     }
1552 
1553     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_REJECTED, 0, 0, NULL);
1554     hfp_connection->call_state = HFP_CALL_IDLE;
1555     hfp_ag_queue_error(hfp_connection);
1556     hfp_ag_run_for_context(hfp_connection);
1557 }
1558 
1559 // hfp_connection is used to identify originating HF
1560 static void hfp_ag_call_sm(hfp_ag_call_event_t event, hfp_connection_t * hfp_connection){
1561 
1562     // allow to intercept call statemachine events
1563     if (hfp_ag_custom_call_sm_handler != NULL){
1564         bool handle_event = (*hfp_ag_custom_call_sm_handler)(event);
1565         if (!handle_event) return;
1566     }
1567 
1568     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1569     int callheld_indicator_index = get_ag_indicator_index_for_name("callheld");
1570     int call_indicator_index = get_ag_indicator_index_for_name("call");
1571 
1572     switch (event){
1573         case HFP_AG_INCOMING_CALL:
1574             switch (hfp_gsm_call_status()){
1575                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1576                     switch (hfp_gsm_callsetup_status()){
1577                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1578                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1579                             hfp_ag_set_callsetup_indicator();
1580                             hfp_ag_trigger_incoming_call_idle();
1581                             log_info("AG rings");
1582                             break;
1583                         default:
1584                             break;
1585                     }
1586                     break;
1587                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1588                     switch (hfp_gsm_callsetup_status()){
1589                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1590                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1591                             hfp_ag_set_callsetup_indicator();
1592                             hfp_ag_trigger_incoming_call_during_active_one();
1593                             log_info("AG call waiting");
1594                             break;
1595                         default:
1596                             break;
1597                     }
1598                     break;
1599                 default:
1600                     break;
1601             }
1602             break;
1603         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG:
1604             switch (hfp_gsm_call_status()){
1605                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1606                     switch (hfp_gsm_callsetup_status()){
1607                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1608                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1609                             hfp_ag_set_call_indicator();
1610                             hfp_ag_set_callsetup_indicator();
1611                             hfp_ag_ag_accept_call();
1612                             log_info("AG answers call, accept call by GSM");
1613                             break;
1614                         default:
1615                             break;
1616                     }
1617                     break;
1618                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1619                     switch (hfp_gsm_callsetup_status()){
1620                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1621                             log_info("AG: current call is placed on hold, incoming call gets active");
1622                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1623                             hfp_ag_set_callsetup_indicator();
1624                             hfp_ag_set_callheld_indicator();
1625                             hfp_ag_transfer_callsetup_state();
1626                             hfp_ag_transfer_callheld_state();
1627                             break;
1628                         default:
1629                             break;
1630                     }
1631                     break;
1632                 default:
1633                     break;
1634             }
1635             break;
1636 
1637         case HFP_AG_HELD_CALL_JOINED_BY_AG:
1638             switch (hfp_gsm_call_status()){
1639                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1640                     switch (hfp_gsm_callheld_status()){
1641                         case HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED:
1642                             log_info("AG: joining held call with active call");
1643                             hfp_gsm_handler(HFP_AG_HELD_CALL_JOINED_BY_AG, 0, 0, NULL);
1644                             hfp_ag_set_callheld_indicator();
1645                             hfp_ag_transfer_callheld_state();
1646                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1647                             break;
1648                         default:
1649                             break;
1650                     }
1651                     break;
1652                 default:
1653                     break;
1654             }
1655             break;
1656 
1657         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF:
1658             switch (hfp_gsm_call_status()){
1659                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1660                     switch (hfp_gsm_callsetup_status()){
1661                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1662                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, 0, 0, NULL);
1663                             hfp_ag_set_callsetup_indicator();
1664                             hfp_ag_set_call_indicator();
1665                             hfp_ag_hf_accept_call(hfp_connection);
1666                             hfp_ag_queue_ok(hfp_connection);
1667                             log_info("HF answers call, accept call by GSM");
1668                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1669                             break;
1670                         default:
1671                             break;
1672                     }
1673                     break;
1674                 default:
1675                     break;
1676             }
1677             break;
1678 
1679         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG:
1680             switch (hfp_gsm_call_status()){
1681                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1682                     switch (hfp_gsm_callsetup_status()){
1683                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1684                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, 0, 0, NULL);
1685                             hfp_ag_response_and_hold_active = true;
1686                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1687                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1688                             // as with regular call
1689                             hfp_ag_set_call_indicator();
1690                             hfp_ag_set_callsetup_indicator();
1691                             hfp_ag_ag_accept_call();
1692                             log_info("AG response and hold - hold by AG");
1693                             break;
1694                         default:
1695                             break;
1696                     }
1697                     break;
1698                 default:
1699                     break;
1700             }
1701             break;
1702 
1703         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF:
1704             switch (hfp_gsm_call_status()){
1705                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1706                     switch (hfp_gsm_callsetup_status()){
1707                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1708                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, 0, 0, NULL);
1709                             hfp_ag_response_and_hold_active = true;
1710                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1711                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1712                             // as with regular call
1713                             hfp_ag_set_call_indicator();
1714                             hfp_ag_set_callsetup_indicator();
1715                             hfp_ag_hf_accept_call(hfp_connection);
1716                             log_info("AG response and hold - hold by HF");
1717                             break;
1718                         default:
1719                             break;
1720                     }
1721                     break;
1722                 default:
1723                     break;
1724             }
1725             break;
1726 
1727         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG:
1728         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF:
1729             if (!hfp_ag_response_and_hold_active) break;
1730             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1731             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, 0, 0, NULL);
1732             hfp_ag_response_and_hold_active = false;
1733             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED;
1734             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1735             log_info("Held Call accepted and active");
1736             break;
1737 
1738         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG:
1739         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF:
1740             if (!hfp_ag_response_and_hold_active) break;
1741             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1742             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, 0, 0, NULL);
1743             hfp_ag_response_and_hold_active = false;
1744             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1745             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1746             // from terminate by ag
1747             hfp_ag_set_call_indicator();
1748             hfp_ag_trigger_terminate_call();
1749             break;
1750 
1751         case HFP_AG_TERMINATE_CALL_BY_HF:
1752             switch (hfp_gsm_call_status()){
1753                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1754                     switch (hfp_gsm_callsetup_status()){
1755                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1756                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1757                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1758                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1759                             hfp_ag_set_callsetup_indicator();
1760                             hfp_ag_transfer_callsetup_state();
1761                             hfp_ag_trigger_reject_call();
1762                             log_info("HF Rejected Incoming call, AG terminate call");
1763                             break;
1764                         default:
1765                             break;
1766                     }
1767                     break;
1768                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1769                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1770                     hfp_ag_set_callsetup_indicator();
1771                     hfp_ag_set_call_indicator();
1772                     hfp_ag_trigger_terminate_call();
1773                     log_info("AG terminate call");
1774                     break;
1775                 default:
1776                     break;
1777             }
1778             break;
1779 
1780         case HFP_AG_TERMINATE_CALL_BY_AG:
1781             switch (hfp_gsm_call_status()){
1782                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1783                     switch (hfp_gsm_callsetup_status()){
1784                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1785                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1786                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1787                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1788                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1789                             hfp_ag_set_callsetup_indicator();
1790                             hfp_ag_trigger_reject_call();
1791                             log_info("AG Rejected Incoming call, AG terminate call");
1792                             break;
1793                         default:
1794                             break;
1795                     }
1796                     break;
1797                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1798                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1799                     hfp_ag_set_callsetup_indicator();
1800                     hfp_ag_set_call_indicator();
1801                     hfp_ag_trigger_terminate_call();
1802                     log_info("AG terminate call");
1803                     break;
1804                 default:
1805                     break;
1806             }
1807             break;
1808         case HFP_AG_CALL_DROPPED:
1809             switch (hfp_gsm_call_status()){
1810                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1811                     switch (hfp_gsm_callsetup_status()){
1812                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1813                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1814                             hfp_ag_stop_ringing();
1815                             break;
1816                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1817                             log_info("Outgoing call interrupted\n");
1818                             break;
1819                         default:
1820                             break;
1821                     }
1822                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1823                     hfp_ag_set_callsetup_indicator();
1824                     hfp_ag_transfer_callsetup_state();
1825                     hfp_ag_trigger_terminate_call();
1826                     break;
1827                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1828                     if (hfp_ag_response_and_hold_active) {
1829                         hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1830                         hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1831                         hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1832                     }
1833                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1834                     hfp_ag_set_callsetup_indicator();
1835                     hfp_ag_set_call_indicator();
1836                     hfp_ag_trigger_terminate_call();
1837                     log_info("AG notify call dropped");
1838                     break;
1839                 default:
1840                     break;
1841             }
1842             break;
1843 
1844         case HFP_AG_OUTGOING_CALL_INITIATED_BY_HF:
1845             // directly reject call if number of free slots is exceeded
1846             if (!hfp_gsm_call_possible()){
1847                 hfp_ag_queue_error(hfp_connection);
1848                 hfp_ag_run_for_context(hfp_connection);
1849                 break;
1850             }
1851 
1852             // note: number not used currently
1853             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, 0, 0, (const char *) &hfp_connection->line_buffer[3]);
1854 
1855             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1856 
1857             hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, (const char *) &hfp_connection->line_buffer[3]);
1858             break;
1859 
1860         case HFP_AG_OUTGOING_CALL_INITIATED_BY_AG:
1861             // directly reject call if number of free slots is exceeded
1862             if (!hfp_gsm_call_possible()) {
1863                 // TODO: no error for user
1864                 break;
1865             }
1866             switch (hfp_gsm_call_status()) {
1867                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1868                     switch (hfp_gsm_callsetup_status()) {
1869                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1870                             // note: number not used currently
1871                             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, 0, 0, "1234567");
1872                             // init call state for all connections
1873                             hfp_ag_trigger_outgoing_call();
1874                             // get first one and accept call
1875                             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1876                             if (hfp_connection) {
1877                                 hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1878                             }
1879                             break;
1880                         default:
1881                             // TODO: no error for user
1882                             break;
1883                     }
1884                     break;
1885                 default:
1886                     // TODO: no error for user
1887                     break;
1888             }
1889             break;
1890         case HFP_AG_OUTGOING_REDIAL_INITIATED:{
1891             // directly reject call if number of free slots is exceeded
1892             if (!hfp_gsm_call_possible()){
1893                 hfp_ag_queue_error(hfp_connection);
1894                 hfp_ag_run_for_context(hfp_connection);
1895                 break;
1896             }
1897 
1898             hfp_gsm_handler(HFP_AG_OUTGOING_REDIAL_INITIATED, 0, 0, NULL);
1899             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1900 
1901             log_info("Redial last number");
1902             char * last_dialed_number = hfp_gsm_last_dialed_number();
1903 
1904             if (strlen(last_dialed_number) > 0){
1905                 log_info("Last number exists: accept call");
1906                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, last_dialed_number);
1907             } else {
1908                 log_info("log_infoLast number missing: reject call");
1909                 hfp_ag_handle_reject_outgoing_call();
1910             }
1911             break;
1912         }
1913         case HFP_AG_OUTGOING_CALL_REJECTED:
1914             hfp_ag_handle_reject_outgoing_call();
1915             break;
1916 
1917         case HFP_AG_OUTGOING_CALL_ACCEPTED:{
1918             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1919             if (!hfp_connection){
1920                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1921                 break;
1922             }
1923 
1924             hfp_ag_queue_ok(hfp_connection);
1925             hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1926             break;
1927         }
1928         case HFP_AG_OUTGOING_CALL_RINGING:
1929             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1930             if (!hfp_connection){
1931                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in dialing state");
1932                 break;
1933             }
1934 
1935             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_RINGING, 0, 0, NULL);
1936             hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1937             hfp_ag_set_callsetup_indicator();
1938             hfp_ag_transfer_callsetup_state();
1939             hfp_ag_hf_start_ringing_outgoing(hfp_connection);
1940             break;
1941 
1942         case HFP_AG_OUTGOING_CALL_ESTABLISHED:{
1943             // get outgoing call
1944             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_RINGING);
1945             if (!hfp_connection){
1946                 hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1947             }
1948             if (!hfp_connection){
1949                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection");
1950                 break;
1951             }
1952 
1953             bool callheld_status_call_on_hold_and_no_active_calls = hfp_gsm_callheld_status() == HFP_CALLHELD_STATUS_CALL_ON_HOLD_AND_NO_ACTIVE_CALLS;
1954             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ESTABLISHED, 0, 0, NULL);
1955             hfp_connection->call_state = HFP_CALL_ACTIVE;
1956             hfp_ag_set_callsetup_indicator();
1957             hfp_ag_set_call_indicator();
1958             hfp_ag_transfer_call_state();
1959             hfp_ag_transfer_callsetup_state();
1960             if (callheld_status_call_on_hold_and_no_active_calls){
1961                 hfp_ag_set_callheld_indicator();
1962                 hfp_ag_transfer_callheld_state();
1963             }
1964             hfp_ag_hf_stop_ringing(hfp_connection);
1965             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1966             break;
1967         }
1968 
1969         case HFP_AG_CALL_HOLD_USER_BUSY:
1970             hfp_gsm_handler(HFP_AG_CALL_HOLD_USER_BUSY, 0, 0, NULL);
1971             hfp_ag_set_callsetup_indicator();
1972             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1973             hfp_connection->call_state = HFP_CALL_ACTIVE;
1974             log_info("AG: Call Waiting, User Busy");
1975             break;
1976 
1977         case HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1978             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1979             int call_held = hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD;
1980 
1981             // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
1982             if (call_held || call_setup_in_progress){
1983                 hfp_gsm_handler(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index,
1984                                 0, NULL);
1985 
1986             }
1987 
1988             if (call_setup_in_progress){
1989                 log_info("AG: Call Dropped, Accept new call");
1990                 hfp_ag_set_callsetup_indicator();
1991                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1992             } else {
1993                 log_info("AG: Call Dropped, Resume held call");
1994             }
1995             if (call_held){
1996                 hfp_ag_set_callheld_indicator();
1997                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1998             }
1999 
2000             hfp_connection->call_state = HFP_CALL_ACTIVE;
2001             break;
2002         }
2003 
2004         case HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
2005             // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
2006             // only update if callsetup changed
2007             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
2008             hfp_gsm_handler(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index, 0,
2009                             NULL);
2010 
2011             if (call_setup_in_progress){
2012                 log_info("AG: Call on Hold, Accept new call");
2013                 hfp_ag_set_callsetup_indicator();
2014                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
2015             } else {
2016                 log_info("AG: Swap calls");
2017             }
2018 
2019             hfp_ag_set_callheld_indicator();
2020             // hfp_ag_set_callheld_state(HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED);
2021             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
2022             hfp_connection->call_state = HFP_CALL_ACTIVE;
2023             break;
2024         }
2025 
2026         case HFP_AG_CALL_HOLD_ADD_HELD_CALL:
2027             // Adds a held call to the conversation.
2028             if (hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD){
2029                 log_info("AG: Join 3-way-call");
2030                 hfp_gsm_handler(HFP_AG_CALL_HOLD_ADD_HELD_CALL, 0, 0, NULL);
2031                 hfp_ag_set_callheld_indicator();
2032                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
2033                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
2034             }
2035             hfp_connection->call_state = HFP_CALL_ACTIVE;
2036             break;
2037         case HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS:
2038             // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer)
2039             hfp_gsm_handler(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, 0, 0, NULL);
2040             log_info("AG: Transfer call -> Connect two calls and disconnect");
2041             hfp_ag_set_call_indicator();
2042             hfp_ag_set_callheld_indicator();
2043             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
2044             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
2045             hfp_connection->call_state = HFP_CALL_IDLE;
2046             break;
2047 
2048         default:
2049             break;
2050     }
2051 
2052 
2053 }
2054 
2055 
2056 static void hfp_ag_send_call_status(hfp_connection_t * hfp_connection, int call_index){
2057     hfp_gsm_call_t * active_call = hfp_gsm_call(call_index);
2058     if (!active_call) return;
2059 
2060     int idx = active_call->index;
2061     hfp_enhanced_call_dir_t dir = active_call->direction;
2062     hfp_enhanced_call_status_t status = active_call->enhanced_status;
2063     hfp_enhanced_call_mode_t mode = active_call->mode;
2064     hfp_enhanced_call_mpty_t mpty = active_call->mpty;
2065     uint8_t type = active_call->clip_type;
2066     char * number = active_call->clip_number;
2067 
2068     char buffer[100];
2069     // TODO: check length of a buffer, to fit the MTU
2070     int offset = snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d,%d,%d,%d", HFP_LIST_CURRENT_CALLS, idx, dir, status, mode, mpty);
2071     if (number){
2072         offset += snprintf(buffer+offset, sizeof(buffer)-offset-3, ", \"%s\",%u", number, type);
2073     }
2074     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n");
2075     log_info("hfp_ag_send_current_call_status 000 index %d, dir %d, status %d, mode %d, mpty %d, type %d, number %s", idx, dir, status,
2076        mode, mpty, type, number);
2077     send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
2078 }
2079 
2080 // sends pending command, returns if command was sent
2081 static int hfp_ag_send_commands(hfp_connection_t *hfp_connection){
2082     if (hfp_connection->send_status_of_current_calls){
2083         if (hfp_connection->next_call_index < hfp_gsm_get_number_of_calls()){
2084             hfp_connection->next_call_index++;
2085             hfp_ag_send_call_status(hfp_connection, hfp_connection->next_call_index);
2086             return 1;
2087         } else {
2088             // TODO: this code should be removed. check a) before setting send_status_of_current_calls, or b) right before hfp_ag_send_call_status above
2089             hfp_connection->next_call_index = 0;
2090             hfp_ag_queue_ok(hfp_connection);
2091             hfp_connection->send_status_of_current_calls = 0;
2092         }
2093     }
2094 
2095     if (hfp_connection->ag_notify_incoming_call_waiting){
2096         hfp_connection->ag_notify_incoming_call_waiting = 0;
2097         hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
2098         return 1;
2099     }
2100 
2101     if (hfp_connection->send_error > 0){
2102         hfp_connection->send_error--;
2103         hfp_connection->command = HFP_CMD_NONE;
2104         hfp_ag_send_error(hfp_connection->rfcomm_cid);
2105         return 1;
2106     }
2107 
2108     // note: before update AG indicators and ok_pending
2109     if (hfp_connection->send_response_and_hold_status){
2110         int status = hfp_connection->send_response_and_hold_status - 1;
2111         hfp_connection->send_response_and_hold_status = 0;
2112         hfp_ag_send_set_response_and_hold(hfp_connection->rfcomm_cid, status);
2113         return 1;
2114     }
2115 
2116     // note: before ok_pending and send_error to allow for unsolicited result on custom command
2117     if (hfp_connection->send_custom_message != NULL){
2118         const char * message = hfp_connection->send_custom_message;
2119         hfp_connection->send_custom_message = NULL;
2120         send_str_over_rfcomm(hfp_connection->rfcomm_cid, message);
2121         hfp_emit_event(hfp_connection, HFP_SUBEVENT_CUSTOM_AT_MESSAGE_SENT, ERROR_CODE_SUCCESS);
2122         return 1;
2123     }
2124 
2125     if (hfp_connection->ok_pending > 0){
2126         hfp_connection->ok_pending--;
2127         hfp_connection->command = HFP_CMD_NONE;
2128         hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2129         return 1;
2130     }
2131 
2132     // update AG indicators only if enabled by AT+CMER=3,0,0,1
2133     if ((hfp_connection->enable_status_update_for_ag_indicators == 1) && (hfp_connection->ag_indicators_status_update_bitmap != 0)){
2134         uint16_t i;
2135         for (i=0;i<hfp_connection->ag_indicators_nr;i++){
2136             if (get_bit(hfp_connection->ag_indicators_status_update_bitmap, i)){
2137                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, i, 0);
2138                 hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[i]);
2139                 return 1;
2140             }
2141         }
2142     }
2143 
2144     if (hfp_connection->ag_send_no_carrier){
2145         hfp_connection->ag_send_no_carrier = false;
2146         hfp_ag_send_no_carrier(hfp_connection->rfcomm_cid);
2147         return 1;
2148     }
2149 
2150     if (hfp_connection->send_phone_number_for_voice_tag){
2151         hfp_connection->send_phone_number_for_voice_tag = 0;
2152         hfp_connection->command = HFP_CMD_NONE;
2153         hfp_ag_queue_ok(hfp_connection);
2154         hfp_ag_send_phone_number_for_voice_tag_cmd(hfp_connection->rfcomm_cid);
2155         return 1;
2156     }
2157 
2158     if (hfp_connection->send_subscriber_number){
2159         if (hfp_connection->next_subscriber_number_to_send < hfp_ag_subscriber_numbers_count){
2160             hfp_phone_number_t phone = hfp_ag_subscriber_numbers[hfp_connection->next_subscriber_number_to_send++];
2161             hfp_send_subscriber_number_cmd(hfp_connection->rfcomm_cid, phone.type, phone.number);
2162         } else {
2163             hfp_connection->send_subscriber_number = 0;
2164             hfp_connection->next_subscriber_number_to_send = 0;
2165             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2166         }
2167         hfp_connection->command = HFP_CMD_NONE;
2168         return 1;
2169     }
2170 
2171     if (hfp_connection->send_microphone_gain){
2172         hfp_connection->send_microphone_gain = 0;
2173         hfp_connection->command = HFP_CMD_NONE;
2174         hfp_ag_send_set_microphone_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->microphone_gain);
2175         return 1;
2176     }
2177 
2178     if (hfp_connection->send_speaker_gain){
2179         hfp_connection->send_speaker_gain = 0;
2180         hfp_connection->command = HFP_CMD_NONE;
2181         hfp_ag_send_set_speaker_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->speaker_gain);
2182         return 1;
2183     }
2184 
2185     if (hfp_connection->send_ag_status_indicators){
2186         hfp_connection->send_ag_status_indicators = 0;
2187         hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
2188         return 1;
2189     }
2190 
2191     if (hfp_connection->extended_audio_gateway_error){
2192         uint8_t extended_audio_gateway_error = hfp_connection->extended_audio_gateway_error;
2193         hfp_connection->extended_audio_gateway_error = 0;
2194         hfp_ag_send_report_extended_audio_gateway_error(hfp_connection->rfcomm_cid, extended_audio_gateway_error);
2195 
2196     }
2197     return 0;
2198 }
2199 
2200 // sends pending command, returns if command was sent
2201 static int hfp_ag_run_ring_and_clip(hfp_connection_t *hfp_connection){
2202     // delay RING/CLIP until audio connection has been established for incoming calls
2203     // hfp_ag_hf_trigger_ring_and_clip is called in call_setup_state_machine
2204     if (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING){
2205         if (hfp_connection->ag_ring){
2206             hfp_connection->ag_ring = 0;
2207             hfp_connection->command = HFP_CMD_NONE;
2208             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_RING);
2209             hfp_ag_send_ring(hfp_connection->rfcomm_cid);
2210             return 1;
2211         }
2212 
2213         if (hfp_connection->ag_send_clip){
2214             hfp_connection->ag_send_clip = 0;
2215             hfp_connection->command = HFP_CMD_NONE;
2216             hfp_ag_send_clip(hfp_connection->rfcomm_cid);
2217             return 1;
2218         }
2219     }
2220     return 0;
2221 }
2222 
2223 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection){
2224 
2225 	btstack_assert(hfp_connection != NULL);
2226 	btstack_assert(hfp_connection->local_role == HFP_ROLE_AG);
2227 
2228 	// during SDP query, RFCOMM CID is not set
2229 	if (hfp_connection->rfcomm_cid == 0) return;
2230 
2231     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED && hfp_connection->emit_vra_enabled_after_audio_established){
2232         hfp_connection->emit_vra_enabled_after_audio_established = false;
2233         hfp_emit_voice_recognition_enabled(hfp_connection, ERROR_CODE_SUCCESS);
2234     }
2235 
2236     if ((hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) && hfp_connection->release_audio_connection){
2237         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
2238         hfp_connection->release_audio_connection = 0;
2239         gap_disconnect(hfp_connection->sco_handle);
2240         return;
2241     }
2242 
2243     // configure NBS/WBS if needed using vendor-specific HCI commands
2244     if (hci_can_send_command_packet_now()) {
2245 #ifdef ENABLE_CC256X_ASSISTED_HFP
2246         // WBS Disassociate
2247         if (hfp_connection->cc256x_send_wbs_disassociate){
2248             hfp_connection->cc256x_send_wbs_disassociate = false;
2249             hci_send_cmd(&hci_ti_wbs_disassociate);
2250             return;
2251         }
2252         // Write Codec Config
2253         if (hfp_connection->cc256x_send_write_codec_config){
2254             hfp_connection->cc256x_send_write_codec_config = false;
2255             hfp_cc256x_write_codec_config(hfp_connection);
2256             return;
2257         }
2258         // WBS Associate
2259         if (hfp_connection->cc256x_send_wbs_associate){
2260             hfp_connection->cc256x_send_wbs_associate = false;
2261             hci_send_cmd(&hci_ti_wbs_associate, hfp_connection->acl_handle);
2262             return;
2263         }
2264 #endif
2265 #ifdef ENABLE_BCM_PCM_WBS
2266         // Enable WBS
2267         if (hfp_connection->bcm_send_enable_wbs){
2268             hfp_connection->bcm_send_enable_wbs = false;
2269             hci_send_cmd(&hci_bcm_enable_wbs, 1, 2);
2270             return;
2271         }
2272         // Write I2S/PCM params
2273         if (hfp_connection->bcm_send_write_i2spcm_interface_param){
2274             hfp_connection->bcm_send_write_i2spcm_interface_param = false;
2275             hfp_bcm_write_i2spcm_interface_param(hfp_connection);
2276             return;
2277         }
2278         // Disable WBS
2279         if (hfp_connection->bcm_send_disable_wbs){
2280             hfp_connection->bcm_send_disable_wbs = false;
2281             hci_send_cmd(&hci_bcm_enable_wbs, 0, 2);
2282             return;
2283         }
2284 #endif
2285 #ifdef ENABLE_RTK_PCM_WBS
2286         // Configure CVSD vs. mSBC
2287         if (hfp_connection->rtk_send_sco_config){
2288             hfp_connection->rtk_send_sco_config = false;
2289             if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
2290                 log_info("RTK SCO: 16k + mSBC");
2291                 hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x00, 0x00, 0x41);
2292             } else {
2293                 log_info("RTK SCO: 16k + CVSD");
2294                 hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x0c, 0x00, 0x01);
2295             }
2296             return;
2297         }
2298 #endif
2299 #ifdef ENABLE_NXP_PCM_WBS
2300         if (hfp_connection->nxp_start_audio_handle != HCI_CON_HANDLE_INVALID){
2301             hci_con_handle_t sco_handle = hfp_connection->nxp_start_audio_handle;
2302             hfp_connection->nxp_start_audio_handle = HCI_CON_HANDLE_INVALID;
2303             hci_send_cmd(&hci_nxp_host_pcm_i2s_audio_config, 0, 0, sco_handle, 0);
2304             return;
2305         }
2306         if (hfp_connection->nxp_stop_audio_handle != HCI_CON_HANDLE_INVALID){
2307             hci_con_handle_t sco_handle = hfp_connection->nxp_stop_audio_handle;
2308             hfp_connection->nxp_stop_audio_handle = HCI_CON_HANDLE_INVALID;
2309             hci_send_cmd(&hci_nxp_host_pcm_i2s_audio_config, 1, 0, sco_handle, 0);
2310             return;
2311         }
2312 #endif
2313     }
2314 
2315 #if defined (ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
2316     if (hfp_connection->state == HFP_W4_WBS_SHUTDOWN){
2317         hfp_finalize_connection_context(hfp_connection);
2318         return;
2319     }
2320 #endif
2321 
2322     if (!rfcomm_can_send_packet_now(hfp_connection->rfcomm_cid)) {
2323         log_info("hfp_ag_run_for_context: request can send for 0x%02x", hfp_connection->rfcomm_cid);
2324         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2325         return;
2326     }
2327 
2328     int cmd_sent = hfp_ag_send_commands(hfp_connection);
2329 
2330     if (!cmd_sent){
2331         cmd_sent = hfp_ag_run_for_context_service_level_connection(hfp_connection);
2332     }
2333 
2334     if (!cmd_sent){
2335         cmd_sent = hfp_ag_run_for_context_service_level_connection_queries(hfp_connection);
2336     }
2337 
2338     if (!cmd_sent){
2339         cmd_sent = call_setup_state_machine(hfp_connection);
2340     }
2341 
2342     if (!cmd_sent){
2343         cmd_sent = hfp_ag_run_for_audio_connection(hfp_connection);
2344     }
2345 
2346     if (!cmd_sent){
2347         cmd_sent = hfp_ag_run_ring_and_clip(hfp_connection);
2348     }
2349 
2350     if (!cmd_sent){
2351         cmd_sent = hfp_ag_voice_recognition_state_machine(hfp_connection);
2352     }
2353 
2354     // disconnect
2355     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && (hfp_connection->state == HFP_W2_DISCONNECT_RFCOMM)){
2356         hfp_connection->state = HFP_W4_RFCOMM_DISCONNECTED;
2357         rfcomm_disconnect(hfp_connection->rfcomm_cid);
2358     }
2359 
2360     if (cmd_sent){
2361         hfp_connection->command = HFP_CMD_NONE;
2362         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2363     }
2364 }
2365 
2366 static int hfp_parser_is_end_of_line(uint8_t byte){
2367     return (byte == '\n') || (byte == '\r');
2368 }
2369 
2370 static void hfp_ag_handle_rfcomm_data(hfp_connection_t * hfp_connection, uint8_t *packet, uint16_t size){
2371     // assertion: size >= 1 as rfcomm.c does not deliver empty packets
2372     if (size < 1) return;
2373     uint8_t status = ERROR_CODE_SUCCESS;
2374 
2375     hfp_log_rfcomm_message("HFP_AG_RX", packet, size);
2376 #ifdef ENABLE_HFP_AT_MESSAGES
2377     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_RECEIVED, (char *) packet);
2378 #endif
2379 
2380     // process messages byte-wise
2381     int pos;
2382     for (pos = 0; pos < size ; pos++){
2383         hfp_parse(hfp_connection, packet[pos], 0);
2384 
2385         // parse until end of line
2386         if (!hfp_parser_is_end_of_line(packet[pos])) continue;
2387 
2388         hfp_generic_status_indicator_t * indicator;
2389         switch(hfp_connection->command){
2390             case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
2391                 hfp_connection->command = HFP_CMD_NONE;
2392                 hfp_connection->ag_vra_requested_by_hf = true;
2393                 break;
2394             case HFP_CMD_RESPONSE_AND_HOLD_QUERY:
2395                 hfp_connection->command = HFP_CMD_NONE;
2396                 if (hfp_ag_response_and_hold_active){
2397                     hfp_connection->send_response_and_hold_status = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD + 1;
2398                 }
2399                 hfp_ag_queue_ok(hfp_connection);
2400                 break;
2401             case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
2402                 hfp_connection->command = HFP_CMD_NONE;
2403                 switch(hfp_connection->ag_response_and_hold_action){
2404                     case HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD:
2405                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, hfp_connection);
2406                         break;
2407                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED:
2408                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF, hfp_connection);
2409                         break;
2410                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED:
2411                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF, hfp_connection);
2412                         break;
2413                     default:
2414                         break;
2415                 }
2416                 hfp_ag_queue_ok(hfp_connection);
2417                 break;
2418             case HFP_CMD_HF_INDICATOR_STATUS:
2419                 hfp_connection->command = HFP_CMD_NONE;
2420 
2421                 if (hfp_connection->parser_indicator_index < hfp_ag_generic_status_indicators_nr){
2422                     indicator = &hfp_ag_generic_status_indicators[hfp_connection->parser_indicator_index];
2423                     switch (indicator->uuid){
2424                         case HFP_HF_INDICATOR_UUID_ENHANCED_SAFETY:
2425                             if (hfp_connection->parser_indicator_value > 1) {
2426                                 hfp_ag_queue_error(hfp_connection);
2427                                 break;
2428                             }
2429                             hfp_ag_queue_ok(hfp_connection);
2430                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2431                             break;
2432                         case HFP_HF_INDICATOR_UUID_BATTERY_LEVEL:
2433                             if (hfp_connection->parser_indicator_value > 100){
2434                                 hfp_ag_queue_error(hfp_connection);
2435                                 break;
2436                             }
2437                             hfp_ag_queue_ok(hfp_connection);
2438                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2439                             break;
2440                         default:
2441                             hfp_ag_queue_error(hfp_connection);
2442                             break;
2443                     }
2444                 } else {
2445                     hfp_ag_queue_error(hfp_connection);
2446                 }
2447                 break;
2448             case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
2449                 // expected by SLC state machine
2450                 if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) break;
2451                 hfp_connection->send_ag_indicators_segment = 0;
2452                 hfp_connection->send_ag_status_indicators = 1;
2453                 break;
2454             case HFP_CMD_LIST_CURRENT_CALLS:
2455                 hfp_connection->command = HFP_CMD_NONE;
2456                 hfp_connection->next_call_index = 0;
2457                 hfp_connection->send_status_of_current_calls = 1;
2458                 break;
2459             case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
2460                 hfp_connection->command = HFP_CMD_NONE;
2461                 if (hfp_ag_subscriber_numbers_count == 0){
2462                     hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2463                     break;
2464                 }
2465                 hfp_connection->next_subscriber_number_to_send = 0;
2466                 hfp_connection->send_subscriber_number = 1;
2467                 break;
2468             case HFP_CMD_TRANSMIT_DTMF_CODES:
2469             {
2470                 hfp_connection->command = HFP_CMD_NONE;
2471                 char buffer[2];
2472                 buffer[0] = (char) hfp_connection->ag_dtmf_code;
2473                 buffer[1] = 0;
2474                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_TRANSMIT_DTMF_CODES, buffer);
2475                 break;
2476             }
2477             case HFP_CMD_HF_REQUEST_PHONE_NUMBER:
2478                 hfp_connection->command = HFP_CMD_NONE;
2479                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_ATTACH_NUMBER_TO_VOICE_TAG);
2480                 break;
2481             case HFP_CMD_TURN_OFF_EC_AND_NR:
2482                 hfp_connection->command = HFP_CMD_NONE;
2483 
2484                 if (get_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION)){
2485                     hfp_ag_queue_ok(hfp_connection);
2486                     status = ERROR_CODE_SUCCESS;
2487                 } else {
2488                     hfp_ag_queue_error(hfp_connection);
2489                     status = ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2490                 }
2491                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_ECHO_CANCELING_AND_NOISE_REDUCTION_DEACTIVATE, status);
2492                 break;
2493             case HFP_CMD_CALL_ANSWERED:
2494                 hfp_connection->command = HFP_CMD_NONE;
2495                 log_info("HFP: ATA");
2496                 hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, hfp_connection);
2497                 break;
2498             case HFP_CMD_HANG_UP_CALL:
2499                 hfp_connection->command = HFP_CMD_NONE;
2500                 hfp_ag_queue_ok(hfp_connection);
2501                 hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_HF, hfp_connection);
2502                 break;
2503             case HFP_CMD_CALL_HOLD: {
2504                 hfp_connection->command = HFP_CMD_NONE;
2505                 hfp_ag_queue_ok(hfp_connection);
2506 
2507                 switch (hfp_connection->ag_call_hold_action){
2508                     case 0:
2509                         // Releases all held calls or sets User Determined User Busy (UDUB) for a waiting call.
2510                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_USER_BUSY, hfp_connection);
2511                         break;
2512                     case 1:
2513                         // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
2514                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2515                         // waiting call (i.e., not to the held call) in conflicting situation.
2516                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2517                         break;
2518                     case 2:
2519                         // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
2520                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2521                         // waiting call (i.e., not to the held call) in conflicting situation.
2522                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2523                         break;
2524                     case 3:
2525                         // Adds a held call to the conversation.
2526                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_ADD_HELD_CALL, hfp_connection);
2527                         break;
2528                     case 4:
2529                         // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer).
2530                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, hfp_connection);
2531                         break;
2532                     default:
2533                         break;
2534                 }
2535 				hfp_connection->call_index = 0;
2536                 break;
2537             }
2538             case HFP_CMD_CALL_PHONE_NUMBER:
2539                 hfp_connection->command = HFP_CMD_NONE;
2540                 hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, hfp_connection);
2541                 break;
2542             case HFP_CMD_REDIAL_LAST_NUMBER:
2543                 hfp_connection->command = HFP_CMD_NONE;
2544                 hfp_ag_call_sm(HFP_AG_OUTGOING_REDIAL_INITIATED, hfp_connection);
2545                 break;
2546             case HFP_CMD_ENABLE_CLIP:
2547                 hfp_connection->command = HFP_CMD_NONE;
2548                 log_info("hfp: clip set, now: %u", hfp_connection->clip_enabled);
2549                 hfp_ag_queue_ok(hfp_connection);
2550                 break;
2551             case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
2552                 hfp_connection->command = HFP_CMD_NONE;
2553                 log_info("hfp: call waiting notification set, now: %u", hfp_connection->call_waiting_notification_enabled);
2554                 hfp_ag_queue_ok(hfp_connection);
2555                 break;
2556             case HFP_CMD_SET_SPEAKER_GAIN:
2557                 hfp_connection->command = HFP_CMD_NONE;
2558                 hfp_ag_queue_ok(hfp_connection);
2559                 log_info("HF speaker gain = %u", hfp_connection->speaker_gain);
2560                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_SPEAKER_VOLUME, hfp_connection->speaker_gain);
2561                 break;
2562             case HFP_CMD_SET_MICROPHONE_GAIN:
2563                 hfp_connection->command = HFP_CMD_NONE;
2564                 hfp_ag_queue_ok(hfp_connection);
2565                 log_info("HF microphone gain = %u", hfp_connection->microphone_gain);
2566                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_MICROPHONE_VOLUME, hfp_connection->microphone_gain);
2567                 break;
2568             case HFP_CMD_CUSTOM_MESSAGE:
2569                 hfp_connection->command = HFP_CMD_NONE;
2570                 hfp_parser_reset_line_buffer(hfp_connection);
2571                 log_info("Custom AT Command ID 0x%04x", hfp_connection->custom_at_command_id);
2572                 hfp_ag_emit_custom_command_event(hfp_connection);
2573                 break;
2574             case HFP_CMD_UNKNOWN:
2575                 hfp_connection->command = HFP_CMD_NONE;
2576                 hfp_ag_queue_error(hfp_connection);
2577                 break;
2578             default:
2579                 break;
2580         }
2581     }
2582 }
2583 
2584 static void hfp_ag_run(void){
2585     btstack_linked_list_iterator_t it;
2586     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2587     while (btstack_linked_list_iterator_has_next(&it)){
2588         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2589         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2590         hfp_ag_run_for_context(hfp_connection);
2591     }
2592 }
2593 
2594 static void hfp_ag_rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2595     hfp_connection_t * hfp_connection = NULL;
2596     switch (packet_type){
2597         case RFCOMM_DATA_PACKET:
2598             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(channel);
2599             btstack_assert(hfp_connection != NULL);
2600 
2601             hfp_ag_handle_rfcomm_data(hfp_connection, packet, size);
2602             hfp_ag_run_for_context(hfp_connection);
2603             return;
2604         case HCI_EVENT_PACKET:
2605             if (packet[0] == RFCOMM_EVENT_CAN_SEND_NOW){
2606                 uint16_t rfcomm_cid = rfcomm_event_can_send_now_get_rfcomm_cid(packet);
2607                 hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
2608                 btstack_assert(hfp_connection != NULL);
2609 
2610                 hfp_ag_run_for_context(hfp_connection);
2611                 return;
2612             }
2613             hfp_handle_rfcomm_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2614             break;
2615         default:
2616             break;
2617     }
2618 
2619     hfp_ag_run();
2620 }
2621 
2622 static void hfp_ag_hci_event_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2623     hfp_handle_hci_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2624     hfp_ag_run();
2625 }
2626 
2627 void hfp_ag_init_codecs(uint8_t codecs_nr, const uint8_t * codecs){
2628     btstack_assert(codecs_nr <= HFP_MAX_NUM_CODECS);
2629 
2630     hfp_ag_codecs_nr = codecs_nr;
2631     uint8_t i;
2632     for (i=0; i < codecs_nr; i++){
2633         hfp_ag_codecs[i] = codecs[i];
2634     }
2635 }
2636 
2637 void hfp_ag_init_supported_features(uint32_t supported_features){
2638     hfp_ag_supported_features = supported_features;
2639     hfp_ag_in_band_ring_tone_active = has_in_band_ring_tone();
2640 }
2641 
2642 void hfp_ag_init_ag_indicators(int ag_indicators_nr, const hfp_ag_indicator_t * ag_indicators){
2643     hfp_ag_indicators_nr = ag_indicators_nr;
2644     (void)memcpy(hfp_ag_indicators, ag_indicators,
2645                  ag_indicators_nr * sizeof(hfp_ag_indicator_t));
2646 }
2647 
2648 void hfp_ag_init_hf_indicators(int hf_indicators_nr, const hfp_generic_status_indicator_t * hf_indicators){
2649     if (hf_indicators_nr > HFP_MAX_NUM_INDICATORS) return;
2650     hfp_ag_generic_status_indicators_nr = hf_indicators_nr;
2651     (void)memcpy(hfp_ag_generic_status_indicators, hf_indicators,
2652                  hf_indicators_nr * sizeof(hfp_generic_status_indicator_t));
2653 }
2654 
2655 void hfp_ag_init_call_hold_services(int call_hold_services_nr, const char * call_hold_services[]){
2656     hfp_ag_call_hold_services_nr = call_hold_services_nr;
2657     (void)memcpy(hfp_ag_call_hold_services, call_hold_services,
2658                  call_hold_services_nr * sizeof(char *));
2659 }
2660 
2661 
2662 void hfp_ag_init(uint8_t rfcomm_channel_nr){
2663 
2664     hfp_init();
2665     hfp_ag_call_hold_services_nr = 0;
2666     hfp_ag_response_and_hold_active = false;
2667     hfp_ag_indicators_nr = 0;
2668     hfp_ag_codecs_nr = 0;
2669     hfp_ag_supported_features = HFP_DEFAULT_AG_SUPPORTED_FEATURES;
2670     hfp_ag_in_band_ring_tone_active = has_in_band_ring_tone();
2671     hfp_ag_subscriber_numbers = NULL;
2672     hfp_ag_subscriber_numbers_count = 0;
2673 
2674     hfp_ag_hci_event_callback_registration.callback = &hfp_ag_hci_event_packet_handler;
2675     hci_add_event_handler(&hfp_ag_hci_event_callback_registration);
2676 
2677     rfcomm_register_service(&hfp_ag_rfcomm_packet_handler, rfcomm_channel_nr, 0xffff);
2678 
2679     // used to set packet handler for outgoing rfcomm connections - could be handled by emitting an event to us
2680     hfp_set_ag_rfcomm_packet_handler(&hfp_ag_rfcomm_packet_handler);
2681 
2682     hfp_gsm_init();
2683 }
2684 
2685 void hfp_ag_deinit(void){
2686     hfp_deinit();
2687     hfp_gsm_deinit();
2688 
2689     hfp_ag_callback = NULL;
2690     hfp_ag_supported_features = 0;
2691     hfp_ag_codecs_nr = 0;
2692     hfp_ag_indicators_nr = 0;
2693     hfp_ag_call_hold_services_nr = 0;
2694     (void) memset(&hfp_ag_call_hold_services, 0, sizeof(hfp_ag_call_hold_services));
2695     hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
2696     (void) memset(&hfp_ag_response_and_hold_state, 0, sizeof(hfp_response_and_hold_state_t));
2697     hfp_ag_subscriber_numbers = NULL;
2698     (void) memset(&hfp_ag_hci_event_callback_registration, 0, sizeof(btstack_packet_callback_registration_t));
2699     hfp_ag_custom_call_sm_handler = NULL;
2700 }
2701 
2702 uint8_t hfp_ag_establish_service_level_connection(bd_addr_t bd_addr){
2703     return hfp_establish_service_level_connection(bd_addr, BLUETOOTH_SERVICE_CLASS_HANDSFREE, HFP_ROLE_AG);
2704 }
2705 
2706 uint8_t hfp_ag_release_service_level_connection(hci_con_handle_t acl_handle){
2707     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2708     if (!hfp_connection){
2709         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2710     }
2711 
2712     hfp_trigger_release_service_level_connection(hfp_connection);
2713     hfp_ag_run_for_context(hfp_connection);
2714     return ERROR_CODE_SUCCESS;
2715 }
2716 
2717 uint8_t hfp_ag_report_extended_audio_gateway_error_result_code(hci_con_handle_t acl_handle, hfp_cme_error_t error){
2718     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2719     if (!hfp_connection){
2720         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2721     }
2722 
2723     if (!hfp_connection->enable_extended_audio_gateway_error_report){
2724         return ERROR_CODE_COMMAND_DISALLOWED;
2725     }
2726 
2727     hfp_connection->extended_audio_gateway_error = error;
2728     hfp_ag_run_for_context(hfp_connection);
2729     return ERROR_CODE_SUCCESS;
2730 }
2731 
2732 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection){
2733     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
2734         return ERROR_CODE_COMMAND_DISALLOWED;
2735     }
2736     if (hfp_connection->state >= HFP_W2_DISCONNECT_SCO){
2737         return ERROR_CODE_COMMAND_DISALLOWED;
2738     }
2739 
2740     hfp_connection->establish_audio_connection = 1;
2741     if (!has_codec_negotiation_feature(hfp_connection)){
2742         log_info("hfp_ag_establish_audio_connection - no codec negotiation feature, using CVSD");
2743         hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
2744         hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
2745         // now, pick link settings
2746         hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
2747 #ifdef ENABLE_CC256X_ASSISTED_HFP
2748         hfp_cc256x_prepare_for_sco(hfp_connection);
2749 #endif
2750         return ERROR_CODE_SUCCESS;
2751     }
2752 
2753     uint8_t i;
2754     bool codec_was_in_use = false;
2755     bool better_codec_can_be_used = false;
2756 
2757     for (i = 0; i<hfp_connection->remote_codecs_nr; i++){
2758         if (hfp_connection->negotiated_codec == hfp_connection->remote_codecs[i]){
2759             codec_was_in_use = true;
2760         } else if (hfp_connection->negotiated_codec < hfp_connection->remote_codecs[i]){
2761             better_codec_can_be_used = true;
2762         }
2763     }
2764 
2765     if (!codec_was_in_use || better_codec_can_be_used){
2766         hfp_connection->ag_send_common_codec = true;
2767         hfp_connection->codecs_state = HFP_CODECS_IDLE;
2768     }
2769     return ERROR_CODE_SUCCESS;
2770 }
2771 
2772 uint8_t hfp_ag_establish_audio_connection(hci_con_handle_t acl_handle){
2773     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2774     if (!hfp_connection){
2775         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2776     }
2777     uint8_t status = hfp_ag_setup_audio_connection(hfp_connection);
2778     if (status != ERROR_CODE_SUCCESS){
2779         return status;
2780     }
2781     hfp_ag_run_for_context(hfp_connection);
2782     return ERROR_CODE_SUCCESS;
2783 }
2784 
2785 uint8_t hfp_ag_release_audio_connection(hci_con_handle_t acl_handle){
2786     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2787     if (!hfp_connection){
2788         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2789     }
2790 
2791     if (hfp_connection->vra_state == HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
2792         return ERROR_CODE_COMMAND_DISALLOWED;
2793     }
2794 
2795     uint8_t status = hfp_trigger_release_audio_connection(hfp_connection);
2796     if (status == ERROR_CODE_SUCCESS){
2797         hfp_ag_run_for_context(hfp_connection);
2798     }
2799     return status;
2800 }
2801 
2802 /**
2803  * @brief Enable in-band ring tone
2804  */
2805 void hfp_ag_set_use_in_band_ring_tone(int use_in_band_ring_tone){
2806     if (has_in_band_ring_tone() == false){
2807         return;
2808     }
2809     if (hfp_ag_in_band_ring_tone_active == use_in_band_ring_tone){
2810         return;
2811     }
2812 
2813     hfp_ag_in_band_ring_tone_active = use_in_band_ring_tone;
2814 
2815     btstack_linked_list_iterator_t it;
2816     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2817     while (btstack_linked_list_iterator_has_next(&it)){
2818         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2819         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2820         hfp_connection->ag_send_in_band_ring_tone_setting = true;
2821         hfp_ag_run_for_context(hfp_connection);
2822     }
2823 }
2824 
2825 /**
2826  * @brief Called from GSM
2827  */
2828 void hfp_ag_incoming_call(void){
2829     hfp_ag_call_sm(HFP_AG_INCOMING_CALL, NULL);
2830 }
2831 
2832 void hfp_ag_outgoing_call_initiated(void) {
2833     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, NULL);
2834 }
2835 
2836 /**
2837  * @brief number is stored.
2838  */
2839 void hfp_ag_set_clip(uint8_t type, const char * number){
2840     hfp_gsm_handler(HFP_AG_SET_CLIP, 0, type, number);
2841 }
2842 
2843 void hfp_ag_call_dropped(void){
2844     hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2845 }
2846 
2847 // call from AG UI
2848 void hfp_ag_answer_incoming_call(void){
2849     hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, NULL);
2850 }
2851 
2852 void hfp_ag_join_held_call(void){
2853     hfp_ag_call_sm(HFP_AG_HELD_CALL_JOINED_BY_AG, NULL);
2854 }
2855 
2856 void hfp_ag_terminate_call(void){
2857     hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_AG, NULL);
2858 }
2859 
2860 void hfp_ag_outgoing_call_ringing(void){
2861     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_RINGING, NULL);
2862 }
2863 
2864 void hfp_ag_outgoing_call_established(void){
2865     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ESTABLISHED, NULL);
2866 }
2867 
2868 void hfp_ag_outgoing_call_rejected(void){
2869     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_REJECTED, NULL);
2870 }
2871 
2872 void hfp_ag_outgoing_call_accepted(void){
2873     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ACCEPTED, NULL);
2874 }
2875 
2876 void hfp_ag_hold_incoming_call(void){
2877     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, NULL);
2878 }
2879 
2880 void hfp_ag_accept_held_incoming_call(void) {
2881     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, NULL);
2882 }
2883 
2884 void hfp_ag_reject_held_incoming_call(void){
2885     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, NULL);
2886 }
2887 
2888 static void hfp_ag_set_ag_indicator(const char * name, int value){
2889     int indicator_index = get_ag_indicator_index_for_name(name);
2890     if (indicator_index < 0) return;
2891     hfp_ag_indicators[indicator_index].status = value;
2892 
2893     btstack_linked_list_iterator_t it;
2894     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2895     while (btstack_linked_list_iterator_has_next(&it)){
2896         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2897         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2898         if (!hfp_connection->ag_indicators[indicator_index].enabled) {
2899             log_info("Requested AG indicator '%s' update to %u, but it is not enabled", hfp_ag_indicators[indicator_index].name, value);
2900             continue;
2901         }
2902         log_info("AG indicator '%s' changed to %u, request transfer status", hfp_ag_indicators[indicator_index].name, value);
2903         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
2904         hfp_ag_run_for_context(hfp_connection);
2905     }
2906 }
2907 
2908 uint8_t hfp_ag_set_registration_status(int registration_status){
2909     if ((registration_status < 0) || (registration_status > 1)){
2910         return ERROR_CODE_COMMAND_DISALLOWED;
2911     }
2912 
2913     if ( (registration_status == 0) && (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT)){
2914 
2915         // if network goes away wihle a call is active:
2916         // - the  call gets dropped
2917         // - we send NO CARRIER
2918         // NOTE: the CALL=0 has to be sent before NO CARRIER
2919 
2920         hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2921 
2922         btstack_linked_list_iterator_t it;
2923         btstack_linked_list_iterator_init(&it, hfp_get_connections());
2924         while (btstack_linked_list_iterator_has_next(&it)){
2925             hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2926             hfp_connection->ag_send_no_carrier = true;
2927         }
2928     }
2929     hfp_ag_set_ag_indicator("service", registration_status);
2930     return ERROR_CODE_SUCCESS;
2931 }
2932 
2933 uint8_t hfp_ag_set_signal_strength(int signal_strength){
2934     if ((signal_strength < 0) || (signal_strength > 5)){
2935         return ERROR_CODE_COMMAND_DISALLOWED;
2936     }
2937 
2938     hfp_ag_set_ag_indicator("signal", signal_strength);
2939     return ERROR_CODE_SUCCESS;
2940 }
2941 
2942 uint8_t hfp_ag_set_roaming_status(int roaming_status){
2943     if ((roaming_status < 0) || (roaming_status > 1)){
2944         return ERROR_CODE_COMMAND_DISALLOWED;
2945     }
2946 
2947     hfp_ag_set_ag_indicator("roam", roaming_status);
2948     return ERROR_CODE_SUCCESS;
2949 }
2950 
2951 uint8_t hfp_ag_set_battery_level(int battery_level){
2952     if ((battery_level < 0) || (battery_level > 5)){
2953         return ERROR_CODE_COMMAND_DISALLOWED;
2954     }
2955     hfp_ag_set_ag_indicator("battchg", battery_level);
2956     return ERROR_CODE_SUCCESS;
2957 }
2958 
2959 uint8_t hfp_ag_activate_voice_recognition(hci_con_handle_t acl_handle){
2960     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2961     if (!hfp_connection){
2962         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2963     }
2964 
2965     if (hfp_connection->emit_vra_enabled_after_audio_established){
2966         return ERROR_CODE_COMMAND_DISALLOWED;
2967     }
2968 
2969     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2970     bool legacy_vra_supported   = hfp_ag_vra_flag_supported(hfp_connection);
2971     if (!enhanced_vra_supported && !legacy_vra_supported){
2972         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2973     }
2974 
2975     if (!hfp_ag_can_activate_voice_recognition(hfp_connection)){
2976         return ERROR_CODE_COMMAND_DISALLOWED;
2977     }
2978 
2979     hfp_connection->ag_activate_voice_recognition_value = 1;
2980     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
2981     hfp_connection->enhanced_voice_recognition_enabled = enhanced_vra_supported;
2982     hfp_connection->ag_audio_connection_opened_before_vra = hfp_ag_is_audio_connection_active(hfp_connection);
2983     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2984     hfp_connection->ag_vra_send_command = true;
2985     hfp_ag_run_for_context(hfp_connection);
2986     return ERROR_CODE_SUCCESS;
2987 }
2988 
2989 uint8_t hfp_ag_deactivate_voice_recognition(hci_con_handle_t acl_handle){
2990     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2991     if (!hfp_connection){
2992         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2993     }
2994 
2995     if (hfp_connection->emit_vra_enabled_after_audio_established){
2996         return ERROR_CODE_COMMAND_DISALLOWED;
2997     }
2998 
2999     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
3000     bool legacy_vra_supported = hfp_ag_vra_flag_supported(hfp_connection);
3001 
3002     if (!enhanced_vra_supported && !legacy_vra_supported){
3003         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3004     }
3005 
3006     if (!hfp_ag_voice_recognition_session_active(hfp_connection)){
3007         return ERROR_CODE_COMMAND_DISALLOWED;
3008     }
3009 
3010     hfp_connection->ag_activate_voice_recognition_value = 0;
3011     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
3012     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
3013     hfp_connection->ag_vra_send_command = true;
3014     hfp_ag_run_for_context(hfp_connection);
3015     return ERROR_CODE_SUCCESS;
3016 }
3017 
3018 static uint8_t hfp_ag_enhanced_voice_recognition_send_state(hci_con_handle_t acl_handle, hfp_voice_recognition_state_t state){
3019     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3020     if (!hfp_connection){
3021         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3022     }
3023 
3024     if (hfp_connection->emit_vra_enabled_after_audio_established){
3025         return ERROR_CODE_COMMAND_DISALLOWED;
3026     }
3027 
3028     if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED){
3029         return ERROR_CODE_COMMAND_DISALLOWED;
3030     }
3031 
3032     if (hfp_connection->vra_state != HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
3033         return ERROR_CODE_COMMAND_DISALLOWED;
3034     }
3035 
3036     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
3037     if (!enhanced_vra_supported ){
3038         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3039     }
3040 
3041 
3042     hfp_connection->ag_vra_state = state;
3043     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS;
3044     hfp_connection->ag_vra_send_command = true;
3045     hfp_ag_run_for_context(hfp_connection);
3046     return ERROR_CODE_SUCCESS;
3047 }
3048 
3049 uint8_t hfp_ag_enhanced_voice_recognition_report_sending_audio(hci_con_handle_t acl_handle){
3050     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_STARTING_SOUND);
3051 }
3052 uint8_t hfp_ag_enhanced_voice_recognition_report_ready_for_audio(hci_con_handle_t acl_handle){
3053     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_READY_TO_ACCEPT_AUDIO_INPUT);
3054 }
3055 uint8_t hfp_ag_enhanced_voice_recognition_report_processing_input(hci_con_handle_t acl_handle){
3056     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_PROCESSING_AUDIO_INPUT);
3057 }
3058 
3059 
3060 uint8_t hfp_ag_enhanced_voice_recognition_send_message(hci_con_handle_t acl_handle, hfp_voice_recognition_state_t state, hfp_voice_recognition_message_t msg){
3061     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3062     if (!hfp_connection){
3063         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3064     }
3065 
3066     if (hfp_connection->emit_vra_enabled_after_audio_established){
3067         return ERROR_CODE_COMMAND_DISALLOWED;
3068     }
3069 
3070     if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED){
3071         return ERROR_CODE_COMMAND_DISALLOWED;
3072     }
3073 
3074     if (hfp_connection->vra_state != HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
3075         return ERROR_CODE_COMMAND_DISALLOWED;
3076     }
3077 
3078     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
3079     if (!enhanced_vra_supported ){
3080         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3081     }
3082 
3083     bool enhanced_vra_msg_supported = hfp_ag_can_send_enhanced_vra_message_flag_supported(hfp_connection);
3084     if (!enhanced_vra_msg_supported ){
3085         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3086     }
3087 
3088     uint16_t message_len = (uint16_t) strlen(msg.text);
3089 
3090     if (message_len > HFP_MAX_VR_TEXT_SIZE){
3091         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3092     }
3093 
3094     if ((HFP_VR_TEXT_HEADER_SIZE + message_len) > hfp_connection->rfcomm_mtu){
3095         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3096     }
3097 
3098     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG;
3099     hfp_connection->ag_msg = msg;
3100     hfp_connection->ag_vra_state = state;
3101     hfp_connection->ag_vra_send_command = true;
3102     hfp_ag_run_for_context(hfp_connection);
3103 
3104     return ERROR_CODE_SUCCESS;
3105 }
3106 
3107 
3108 uint8_t hfp_ag_set_microphone_gain(hci_con_handle_t acl_handle, int gain){
3109     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3110     if (!hfp_connection){
3111         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3112     }
3113 
3114     if ((gain < 0) || (gain > 15)){
3115         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
3116         return ERROR_CODE_COMMAND_DISALLOWED;
3117     }
3118 
3119     if (hfp_connection->microphone_gain != gain){
3120         hfp_connection->microphone_gain = gain;
3121         hfp_connection->send_microphone_gain = 1;
3122     }
3123     hfp_ag_run_for_context(hfp_connection);
3124     return ERROR_CODE_SUCCESS;
3125 }
3126 
3127 uint8_t hfp_ag_set_speaker_gain(hci_con_handle_t acl_handle, int gain){
3128     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3129     if (!hfp_connection){
3130         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3131     }
3132 
3133     if ((gain < 0) || (gain > 15)){
3134         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
3135         return ERROR_CODE_COMMAND_DISALLOWED;
3136     }
3137 
3138     if (hfp_connection->speaker_gain != gain){
3139         hfp_connection->speaker_gain = gain;
3140         hfp_connection->send_speaker_gain = 1;
3141     }
3142     hfp_ag_run_for_context(hfp_connection);
3143     return ERROR_CODE_SUCCESS;
3144 }
3145 
3146 uint8_t hfp_ag_send_phone_number_for_voice_tag(hci_con_handle_t acl_handle, const char * number){
3147     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3148     if (!hfp_connection){
3149         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3150     }
3151 
3152     hfp_ag_set_clip(0, number);
3153     hfp_connection->send_phone_number_for_voice_tag = 1;
3154     return ERROR_CODE_SUCCESS;
3155 }
3156 
3157 uint8_t hfp_ag_reject_phone_number_for_voice_tag(hci_con_handle_t acl_handle){
3158     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3159     if (!hfp_connection){
3160         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3161     }
3162 
3163     hfp_ag_queue_error(hfp_connection);
3164     return ERROR_CODE_SUCCESS;
3165 }
3166 
3167 uint8_t hfp_ag_send_dtmf_code_done(hci_con_handle_t acl_handle){
3168     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3169     if (!hfp_connection){
3170         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3171     }
3172 
3173     hfp_ag_queue_ok(hfp_connection);
3174     return ERROR_CODE_SUCCESS;
3175 }
3176 
3177 uint8_t hfp_ag_send_unsolicited_result_code(hci_con_handle_t acl_handle, const char * unsolicited_result_code){
3178     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3179     if (!hfp_connection){
3180         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3181     }
3182     if (hfp_connection->send_custom_message != NULL){
3183         return ERROR_CODE_COMMAND_DISALLOWED;
3184     }
3185     hfp_connection->send_custom_message = unsolicited_result_code;
3186     hfp_ag_run_for_context(hfp_connection);
3187     return ERROR_CODE_SUCCESS;
3188 }
3189 
3190 uint8_t hfp_ag_send_command_result_code(hci_con_handle_t acl_handle, bool ok){
3191     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3192     if (!hfp_connection){
3193         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3194     }
3195     if (ok){
3196         hfp_ag_queue_ok(hfp_connection);
3197     } else {
3198         hfp_ag_queue_error(hfp_connection);
3199     }
3200     hfp_ag_run_for_context(hfp_connection);
3201     return ERROR_CODE_SUCCESS;
3202 }
3203 
3204 void hfp_ag_set_subcriber_number_information(hfp_phone_number_t * numbers, int numbers_count){
3205     hfp_ag_subscriber_numbers = numbers;
3206     hfp_ag_subscriber_numbers_count = numbers_count;
3207 }
3208 
3209 void hfp_ag_clear_last_dialed_number(void){
3210     hfp_gsm_clear_last_dialed_number();
3211 }
3212 
3213 void hfp_ag_set_last_dialed_number(const char * number){
3214     hfp_gsm_set_last_dialed_number(number);
3215 }
3216 
3217 uint8_t hfp_ag_notify_incoming_call_waiting(hci_con_handle_t acl_handle){
3218     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3219     if (!hfp_connection){
3220         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3221     }
3222 
3223     if (!hfp_connection->call_waiting_notification_enabled){
3224         return ERROR_CODE_COMMAND_DISALLOWED;
3225     }
3226 
3227     hfp_connection->ag_notify_incoming_call_waiting = 1;
3228     hfp_ag_run_for_context(hfp_connection);
3229     return ERROR_CODE_SUCCESS;
3230 }
3231 void hfp_ag_create_sdp_record_with_codecs(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr,
3232                                           const char * name, uint8_t ability_to_reject_call, uint16_t supported_features,
3233                                           uint8_t codecs_nr, const uint8_t * codecs){
3234     if (!name){
3235         name = hfp_ag_default_service_name;
3236     }
3237     hfp_create_sdp_record(service, service_record_handle, BLUETOOTH_SERVICE_CLASS_HANDSFREE_AUDIO_GATEWAY, rfcomm_channel_nr, name);
3238 
3239     /*
3240      * 0x01 – Ability to reject a call
3241      * 0x00 – No ability to reject a call
3242      */
3243     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0301);    // Hands-Free Profile - Network
3244     de_add_number(service, DE_UINT, DE_SIZE_8, ability_to_reject_call);
3245 
3246     // Construct SupportedFeatures for SDP bitmap:
3247     //
3248     // "The values of the “SupportedFeatures” bitmap given in Table 5.4 shall be the same as the values
3249     //  of the Bits 0 to 4 of the unsolicited result code +BRSF"
3250     //
3251     // Wide band speech (bit 5) and LC3-SWB (bit 8) require Codec negotiation
3252     //
3253     uint16_t sdp_features = supported_features & 0x1f;
3254 
3255     if (supported_features & (1 << HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS)){
3256         sdp_features |= 1 << 6;
3257     }
3258 
3259     if (supported_features & (1 << HFP_AGSF_VOICE_RECOGNITION_TEXT)){
3260         sdp_features |= 1 << 7;
3261     }
3262 
3263     // codecs
3264     if ((supported_features & (1 << HFP_HFSF_CODEC_NEGOTIATION)) != 0){
3265         uint8_t i;
3266         for (i=0;i<codecs_nr;i++){
3267             switch (codecs[i]){
3268                 case HFP_CODEC_MSBC:
3269                     sdp_features |= 1 << 5;
3270                     break;
3271                 case HFP_CODEC_LC3_SWB:
3272                     sdp_features |= 1 << 8;
3273                     break;
3274                 default:
3275                     break;
3276             }
3277         }
3278     }
3279 
3280     de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);    // Hands-Free Profile - SupportedFeatures
3281     de_add_number(service, DE_UINT, DE_SIZE_16, sdp_features);
3282 }
3283 
3284 void hfp_ag_create_sdp_record(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr, const char * name,
3285                               uint8_t ability_to_reject_call, uint16_t supported_features, int wide_band_speech){
3286     uint8_t codecs_nr;
3287     const uint8_t * codecs;
3288     const uint8_t wide_band_codecs[] = { HFP_CODEC_MSBC };
3289     if (wide_band_speech == 0){
3290         codecs_nr = 0;
3291         codecs = NULL;
3292     } else {
3293         codecs_nr = 1;
3294         codecs = wide_band_codecs;
3295     }
3296     hfp_ag_create_sdp_record_with_codecs(service, service_record_handle, rfcomm_channel_nr, name,
3297                                          ability_to_reject_call, supported_features, codecs_nr, codecs);
3298 }
3299 
3300 void hfp_ag_register_packet_handler(btstack_packet_handler_t callback){
3301 	btstack_assert(callback != NULL);
3302 
3303 	hfp_ag_callback = callback;
3304 	hfp_set_ag_callback(callback);
3305 }
3306 
3307 void hfp_ag_register_custom_call_sm_handler(bool (*handler)(hfp_ag_call_event_t event)){
3308     hfp_ag_custom_call_sm_handler = handler;
3309 }
3310 
3311 void hfp_ag_register_custom_at_command(hfp_custom_at_command_t * custom_at_command){
3312     hfp_register_custom_ag_command(custom_at_command);
3313 }
3314