xref: /btstack/src/classic/hfp_ag.c (revision b7e273518cd9f4945c397269be4329336dd36f70)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hfp_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 btstack_packet_callback_registration_t hfp_ag_hci_event_callback_registration;
95 
96 static uint16_t hfp_ag_supported_features;
97 
98 // codecs
99 static uint8_t hfp_ag_codecs_nr;
100 static uint8_t hfp_ag_codecs[HFP_MAX_NUM_CODECS];
101 
102 // AG indicators
103 static int                hfp_ag_indicators_nr;
104 static hfp_ag_indicator_t hfp_ag_indicators[HFP_MAX_NUM_INDICATORS];
105 
106 // generic status indicators
107 static int                            hfp_ag_generic_status_indicators_nr;
108 static hfp_generic_status_indicator_t hfp_ag_generic_status_indicators[HFP_MAX_NUM_INDICATORS];
109 
110 static int    hfp_ag_call_hold_services_nr;
111 static char * hfp_ag_call_hold_services[6];
112 
113 static hfp_response_and_hold_state_t hfp_ag_response_and_hold_state;
114 static int hfp_ag_response_and_hold_active;
115 
116 // Subscriber information entries
117 static hfp_phone_number_t * hfp_ag_subscriber_numbers;
118 static int                  hfp_ag_subscriber_numbers_count;
119 
120 // call state
121 static btstack_timer_source_t hfp_ag_ring_timeout;
122 
123 // code
124 static int hfp_ag_get_ag_indicators_nr(hfp_connection_t * hfp_connection){
125     if (hfp_connection->ag_indicators_nr != hfp_ag_indicators_nr){
126         hfp_connection->ag_indicators_nr = hfp_ag_indicators_nr;
127         (void)memcpy(hfp_connection->ag_indicators, hfp_ag_indicators,
128                      hfp_ag_indicators_nr * sizeof(hfp_ag_indicator_t));
129     }
130     return hfp_connection->ag_indicators_nr;
131 }
132 
133 hfp_ag_indicator_t * hfp_ag_get_ag_indicators(hfp_connection_t * hfp_connection){
134     // TODO: save only value, and value changed in the hfp_connection?
135     if (hfp_connection->ag_indicators_nr != hfp_ag_indicators_nr){
136         hfp_connection->ag_indicators_nr = hfp_ag_indicators_nr;
137         (void)memcpy(hfp_connection->ag_indicators, hfp_ag_indicators,
138                      hfp_ag_indicators_nr * sizeof(hfp_ag_indicator_t));
139     }
140     return (hfp_ag_indicator_t *)&(hfp_connection->ag_indicators);
141 }
142 
143 static hfp_ag_indicator_t * get_ag_indicator_for_name(const char * name){
144     int i;
145     for (i = 0; i < hfp_ag_indicators_nr; i++){
146         if (strcmp(hfp_ag_indicators[i].name, name) == 0){
147             return &hfp_ag_indicators[i];
148         }
149     }
150     return NULL;
151 }
152 
153 static int get_ag_indicator_index_for_name(const char * name){
154     int i;
155     for (i = 0; i < hfp_ag_indicators_nr; i++){
156         if (strcmp(hfp_ag_indicators[i].name, name) == 0){
157             return i;
158         }
159     }
160     return -1;
161 }
162 
163 static hfp_connection_t * get_hfp_ag_connection_context_for_acl_handle(uint16_t handle){
164     btstack_linked_list_iterator_t it;
165     btstack_linked_list_iterator_init(&it, hfp_get_connections());
166     while (btstack_linked_list_iterator_has_next(&it)){
167         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
168         if (hfp_connection->acl_handle != handle)      continue;
169         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
170         return hfp_connection;
171     }
172     return NULL;
173 }
174 
175 static int use_in_band_tone(void){
176     return get_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE);
177 }
178 
179 static int has_codec_negotiation_feature(hfp_connection_t * hfp_connection){
180     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_CODEC_NEGOTIATION);
181     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_CODEC_NEGOTIATION);
182     return hf && ag;
183 }
184 
185 static int has_call_waiting_and_3way_calling_feature(hfp_connection_t * hfp_connection){
186     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_THREE_WAY_CALLING);
187     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_THREE_WAY_CALLING);
188     return hf && ag;
189 }
190 
191 static int has_hf_indicators_feature(hfp_connection_t * hfp_connection){
192     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_HF_INDICATORS);
193     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_HF_INDICATORS);
194     return hf && ag;
195 }
196 
197 /* unsolicited responses */
198 
199 static int hfp_ag_send_change_in_band_ring_tone_setting_cmd(uint16_t cid){
200     char buffer[20];
201     snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n",
202              HFP_CHANGE_IN_BAND_RING_TONE_SETTING, use_in_band_tone());
203     buffer[sizeof(buffer) - 1] = 0;
204     return send_str_over_rfcomm(cid, buffer);
205 }
206 
207 static int hfp_ag_exchange_supported_features_cmd(uint16_t cid){
208     char buffer[40];
209     snprintf(buffer, sizeof(buffer), "\r\n%s:%d\r\n\r\nOK\r\n",
210              HFP_SUPPORTED_FEATURES, hfp_ag_supported_features);
211     buffer[sizeof(buffer) - 1] = 0;
212     return send_str_over_rfcomm(cid, buffer);
213 }
214 
215 static int hfp_ag_send_ok(uint16_t cid){
216     char buffer[10];
217     snprintf(buffer, sizeof(buffer), "\r\nOK\r\n");
218     buffer[sizeof(buffer) - 1] = 0;
219     return send_str_over_rfcomm(cid, buffer);
220 }
221 
222 static int hfp_ag_send_ring(uint16_t cid){
223     return send_str_over_rfcomm(cid, (char *) "\r\nRING\r\n");
224 }
225 
226 static int hfp_ag_send_no_carrier(uint16_t cid){
227     char buffer[15];
228     snprintf(buffer, sizeof(buffer), "\r\nNO CARRIER\r\n");
229     buffer[sizeof(buffer) - 1] = 0;
230     return send_str_over_rfcomm(cid, buffer);
231 }
232 
233 static int hfp_ag_send_clip(uint16_t cid){
234     char buffer[50];
235     snprintf(buffer, sizeof(buffer), "\r\n%s: \"%s\",%u\r\n", HFP_ENABLE_CLIP,
236              hfp_gsm_clip_number(), hfp_gsm_clip_type());
237     buffer[sizeof(buffer) - 1] = 0;
238     return send_str_over_rfcomm(cid, buffer);
239 }
240 
241 static int hfp_send_subscriber_number_cmd(uint16_t cid, uint8_t type, const char * number){
242     char buffer[50];
243     snprintf(buffer, sizeof(buffer), "\r\n%s: ,\"%s\",%u, , \r\n",
244              HFP_SUBSCRIBER_NUMBER_INFORMATION, number, type);
245     buffer[sizeof(buffer) - 1] = 0;
246     return send_str_over_rfcomm(cid, buffer);
247 }
248 
249 static int hfp_ag_send_phone_number_for_voice_tag_cmd(uint16_t cid){
250     char buffer[50];
251     snprintf(buffer, sizeof(buffer), "\r\n%s: %s\r\n",
252              HFP_PHONE_NUMBER_FOR_VOICE_TAG, hfp_gsm_clip_number());
253     buffer[sizeof(buffer) - 1] = 0;
254     return send_str_over_rfcomm(cid, buffer);
255 }
256 
257 static int hfp_ag_send_call_waiting_notification(uint16_t cid){
258     char buffer[50];
259     snprintf(buffer, sizeof(buffer), "\r\n%s: \"%s\",%u\r\n",
260              HFP_ENABLE_CALL_WAITING_NOTIFICATION, hfp_gsm_clip_number(),
261              hfp_gsm_clip_type());
262     buffer[sizeof(buffer) - 1] = 0;
263     return send_str_over_rfcomm(cid, buffer);
264 }
265 
266 static int hfp_ag_send_error(uint16_t cid){
267     char buffer[10];
268     snprintf(buffer, sizeof(buffer), "\r\nERROR\r\n");
269     buffer[sizeof(buffer) - 1] = 0;
270     return send_str_over_rfcomm(cid, buffer);
271 }
272 
273 static int hfp_ag_send_report_extended_audio_gateway_error(uint16_t cid, uint8_t error){
274     char buffer[20];
275     snprintf(buffer, sizeof(buffer), "\r\n%s=%d\r\n",
276              HFP_EXTENDED_AUDIO_GATEWAY_ERROR, error);
277     buffer[sizeof(buffer) - 1] = 0;
278     return send_str_over_rfcomm(cid, buffer);
279 }
280 
281 // get size for indicator string
282 static int hfp_ag_indicators_string_size(hfp_connection_t * hfp_connection, int i){
283     // template: ("$NAME",($MIN,$MAX))
284     return 8 + (int) strlen(hfp_ag_get_ag_indicators(hfp_connection)[i].name)
285          + string_len_for_uint32(hfp_ag_get_ag_indicators(hfp_connection)[i].min_range)
286          + string_len_for_uint32(hfp_ag_get_ag_indicators(hfp_connection)[i].min_range);
287 }
288 
289 // store indicator
290 static void hfp_ag_indicators_string_store(hfp_connection_t * hfp_connection, int i, uint8_t * buffer, uint16_t buffer_size){
291     snprintf((char *)buffer, buffer_size, "(\"%s\",(%d,%d)),",
292              hfp_ag_get_ag_indicators(hfp_connection)[i].name,
293              hfp_ag_get_ag_indicators(hfp_connection)[i].min_range,
294              hfp_ag_get_ag_indicators(hfp_connection)[i].max_range);
295     ((char *)buffer)[buffer_size - 1] = 0;
296 }
297 
298 // structure: header [indicator [comma indicator]] footer
299 static int hfp_ag_indicators_cmd_generator_num_segments(hfp_connection_t * hfp_connection){
300     int num_indicators = hfp_ag_get_ag_indicators_nr(hfp_connection);
301     if (!num_indicators) return 2;
302     return 3 + ((num_indicators-1) * 2);
303 }
304 
305 // get size of individual segment for hfp_ag_retrieve_indicators_cmd
306 static int hfp_ag_indicators_cmd_generator_get_segment_len(hfp_connection_t * hfp_connection, int index){
307     if (index == 0) {
308         return strlen(HFP_INDICATOR) + 3;   // "\n\r%s:""
309     }
310     index--;
311     int num_indicators = hfp_ag_get_ag_indicators_nr(hfp_connection);
312     int indicator_index = index >> 1;
313     if ((index & 1) == 0){
314         return hfp_ag_indicators_string_size(hfp_connection, indicator_index);
315     }
316     if (indicator_index == (num_indicators - 1)){
317         return 8; // "\r\n\r\nOK\r\n"
318     }
319     return 1; // comma
320 }
321 
322 static void hfp_ag_indicators_cmd_generator_store_segment(hfp_connection_t * hfp_connection, int index, uint8_t * buffer, uint16_t buffer_size){
323     if (index == 0){
324         *buffer++ = '\r';
325         *buffer++ = '\n';
326         int len = strlen(HFP_INDICATOR);
327         (void)memcpy(buffer, HFP_INDICATOR, len);
328         buffer += len;
329         *buffer++ = ':';
330         return;
331     }
332     index--;
333     int num_indicators = hfp_ag_get_ag_indicators_nr(hfp_connection);
334     int indicator_index = index >> 1;
335     if ((index & 1) == 0){
336         hfp_ag_indicators_string_store(hfp_connection, indicator_index, buffer, buffer_size);
337         return;
338     }
339     if (indicator_index == (num_indicators-1)){
340         (void)memcpy(buffer, "\r\n\r\nOK\r\n", 8);
341         return;
342     }
343     *buffer = ',';
344 }
345 
346 static int hfp_ag_generic_indicators_join(char * buffer, int buffer_size){
347     if (buffer_size < (hfp_ag_indicators_nr * 3)) return 0;
348     int i;
349     int offset = 0;
350     for (i = 0; i < (hfp_ag_generic_status_indicators_nr - 1); i++) {
351         offset += snprintf(buffer+offset, buffer_size-offset, "%d,", hfp_ag_generic_status_indicators[i].uuid);
352     }
353     if (i < hfp_ag_generic_status_indicators_nr){
354         offset += snprintf(buffer+offset, buffer_size-offset, "%d", hfp_ag_generic_status_indicators[i].uuid);
355     }
356     return offset;
357 }
358 
359 static int hfp_ag_generic_indicators_initial_status_join(char * buffer, int buffer_size){
360     if (buffer_size < (hfp_ag_generic_status_indicators_nr * 3)) return 0;
361     int i;
362     int offset = 0;
363     for (i = 0; i < hfp_ag_generic_status_indicators_nr; i++) {
364         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);
365     }
366     return offset;
367 }
368 
369 static int hfp_ag_indicators_status_join(char * buffer, int buffer_size){
370     if (buffer_size < (hfp_ag_indicators_nr * 3)) return 0;
371     int i;
372     int offset = 0;
373     for (i = 0; i < (hfp_ag_indicators_nr-1); i++) {
374         offset += snprintf(buffer+offset, buffer_size-offset, "%d,", hfp_ag_indicators[i].status);
375     }
376     if (i<hfp_ag_indicators_nr){
377         offset += snprintf(buffer+offset, buffer_size-offset, "%d", hfp_ag_indicators[i].status);
378     }
379     return offset;
380 }
381 
382 static int hfp_ag_call_services_join(char * buffer, int buffer_size){
383     if (buffer_size < (hfp_ag_call_hold_services_nr * 3)) return 0;
384     int i;
385     int offset = snprintf(buffer, buffer_size, "(");
386     for (i = 0; i < (hfp_ag_call_hold_services_nr-1); i++) {
387         offset += snprintf(buffer+offset, buffer_size-offset, "%s,", hfp_ag_call_hold_services[i]);
388     }
389     if (i<hfp_ag_call_hold_services_nr){
390         offset += snprintf(buffer+offset, buffer_size-offset, "%s)", hfp_ag_call_hold_services[i]);
391     }
392     return offset;
393 }
394 
395 static int hfp_ag_send_cmd_via_generator(uint16_t cid, hfp_connection_t * hfp_connection,
396     int start_segment, int num_segments,
397     int (*get_segment_len)(hfp_connection_t * hfp_connection, int segment),
398     void (*store_segment) (hfp_connection_t * hfp_connection, int segment, uint8_t * buffer, uint16_t buffer_size)){
399 
400     // assumes: can send now == true
401     // assumes: num segments > 0
402     // assumes: individual segments are smaller than MTU
403     rfcomm_reserve_packet_buffer();
404     int mtu = rfcomm_get_max_frame_size(cid);
405     uint8_t * data = rfcomm_get_outgoing_buffer();
406     int offset = 0;
407     int segment = start_segment;
408     while (segment < num_segments){
409         int segment_len = get_segment_len(hfp_connection, segment);
410         if ((offset + segment_len + 1) > mtu) break;
411         // append segment. As it appends a '\0', we provide a buffer one byte larger
412         store_segment(hfp_connection, segment, data+offset, segment_len + 1);
413         offset += segment_len;
414         segment++;
415     }
416     rfcomm_send_prepared(cid, offset);
417 #ifdef ENABLE_HFP_AT_MESSAGES
418     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_SENT, (char *) data);
419 #endif
420     return segment;
421 }
422 
423 // returns next segment to store
424 static int hfp_ag_send_retrieve_indicators_cmd_via_generator(uint16_t cid, hfp_connection_t * hfp_connection, int start_segment){
425     int num_segments = hfp_ag_indicators_cmd_generator_num_segments(hfp_connection);
426     return hfp_ag_send_cmd_via_generator(cid, hfp_connection, start_segment, num_segments,
427                                          hfp_ag_indicators_cmd_generator_get_segment_len,
428                                          hfp_ag_indicators_cmd_generator_store_segment);
429 }
430 
431 static int hfp_ag_send_retrieve_indicators_status_cmd(uint16_t cid){
432     char buffer[40];
433     const int size = sizeof(buffer);
434     int offset = snprintf(buffer, size, "\r\n%s:", HFP_INDICATOR);
435     offset += hfp_ag_indicators_status_join(buffer+offset, size-offset-9);
436     offset += snprintf(buffer+offset, size-offset, "\r\n\r\nOK\r\n");
437     return send_str_over_rfcomm(cid, buffer);
438 }
439 
440 static int hfp_ag_send_retrieve_can_hold_call_cmd(uint16_t cid){
441     char buffer[40];
442     const int size = sizeof(buffer);
443     int offset = snprintf(buffer, size, "\r\n%s:", HFP_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES);
444     offset += hfp_ag_call_services_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 
450 static int hfp_ag_send_list_supported_generic_status_indicators_cmd(uint16_t cid){
451     return hfp_ag_send_ok(cid);
452 }
453 
454 static int hfp_ag_send_retrieve_supported_generic_status_indicators_cmd(uint16_t cid){
455     char buffer[40];
456     const int size = sizeof(buffer);
457     int offset = snprintf(buffer, size, "\r\n%s:(", HFP_GENERIC_STATUS_INDICATOR);
458     offset += hfp_ag_generic_indicators_join(buffer + offset, size - offset - 10);
459     offset += snprintf(buffer+offset, size-offset, ")\r\n\r\nOK\r\n");
460     return send_str_over_rfcomm(cid, buffer);
461 }
462 
463 static int hfp_ag_send_retrieve_initital_supported_generic_status_indicators_cmd(uint16_t cid){
464     char buffer[40];
465     int offset = hfp_ag_generic_indicators_initial_status_join(buffer, sizeof(buffer) - 7);
466     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\nOK\r\n");
467     return send_str_over_rfcomm(cid, buffer);
468 }
469 
470 static int hfp_ag_send_transfer_ag_indicators_status_cmd(uint16_t cid, hfp_ag_indicator_t * indicator){
471     char buffer[20];
472     snprintf(buffer, sizeof(buffer), "\r\n%s:%d,%d\r\n",
473              HFP_TRANSFER_AG_INDICATOR_STATUS, indicator->index,
474              indicator->status);
475     buffer[sizeof(buffer) - 1] = 0;
476     return send_str_over_rfcomm(cid, buffer);
477 }
478 
479 static int hfp_ag_send_report_network_operator_name_cmd(uint16_t cid, hfp_network_opearator_t op){
480     char buffer[41];
481     if (strlen(op.name) == 0){
482         snprintf(buffer, sizeof(buffer), "\r\n%s:%d,,\r\n\r\nOK\r\n", HFP_QUERY_OPERATOR_SELECTION, op.mode);
483     } else {
484         int offset = snprintf(buffer,  sizeof(buffer), "\r\n%s:%d,%d,", HFP_QUERY_OPERATOR_SELECTION, op.mode, op.format);
485         offset += snprintf(buffer+offset, 16, "%s", op.name);
486         snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n\r\nOK\r\n");
487     }
488     return send_str_over_rfcomm(cid, buffer);
489 }
490 
491 static inline int hfp_ag_send_cmd_with_space_and_int(uint16_t cid, const char * cmd, uint8_t value){
492     char buffer[30];
493     snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n", cmd, value);
494     return send_str_over_rfcomm(cid, buffer);
495 }
496 
497 
498 static inline int hfp_ag_send_cmd_with_int(uint16_t cid, const char * cmd, uint8_t value){
499     char buffer[30];
500     snprintf(buffer, sizeof(buffer), "\r\n%s:%d\r\n", cmd, value);
501     return send_str_over_rfcomm(cid, buffer);
502 }
503 
504 static int hfp_ag_send_suggest_codec_cmd(uint16_t cid, uint8_t codec){
505     return hfp_ag_send_cmd_with_int(cid, HFP_CONFIRM_COMMON_CODEC, codec);
506 }
507 
508 static int hfp_ag_send_set_speaker_gain_cmd(uint16_t cid, uint8_t gain){
509     return hfp_ag_send_cmd_with_int(cid, HFP_SET_SPEAKER_GAIN, gain);
510 }
511 
512 static int hfp_ag_send_set_microphone_gain_cmd(uint16_t cid, uint8_t gain){
513     return hfp_ag_send_cmd_with_int(cid, HFP_SET_MICROPHONE_GAIN, gain);
514 }
515 
516 static int hfp_ag_send_set_response_and_hold(uint16_t cid, int state){
517     return hfp_ag_send_cmd_with_space_and_int(cid, HFP_RESPONSE_AND_HOLD, state);
518 }
519 
520 static int hfp_ag_send_enhanced_voice_recognition_state_cmd(hfp_connection_t * hfp_connection){
521     char buffer[30];
522     snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, hfp_connection->enhanced_voice_recognition_enabled, hfp_connection->ag_vra_state);
523     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
524 }
525 
526 static int hfp_ag_send_voice_recognition_cmd(hfp_connection_t * hfp_connection, uint8_t activate_voice_recognition){
527     char buffer[30];
528     if (hfp_connection->enhanced_voice_recognition_enabled){
529         snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, activate_voice_recognition, hfp_connection->ag_vra_state);
530     } else {
531         snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, activate_voice_recognition);
532     }
533     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
534 }
535 
536 static int hfp_ag_send_enhanced_voice_recognition_msg_cmd(hfp_connection_t * hfp_connection){
537     char buffer[100];
538     snprintf(buffer, sizeof(buffer), "\r\n%s: 1,%d,%X,%d,%d,\"%s\"\r\n", HFP_ACTIVATE_VOICE_RECOGNITION,
539         hfp_connection->ag_vra_state,
540         hfp_connection->ag_msg.text_id,
541         hfp_connection->ag_msg.text_type,
542         hfp_connection->ag_msg.text_operation,
543         hfp_connection->ag_msg.text);
544     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
545 }
546 
547 static uint8_t hfp_ag_suggest_codec(hfp_connection_t *hfp_connection){
548     if (hfp_connection->sco_for_msbc_failed) return HFP_CODEC_CVSD;
549 
550     if (hfp_supports_codec(HFP_CODEC_MSBC, hfp_ag_codecs_nr, hfp_ag_codecs)){
551         if (hfp_supports_codec(HFP_CODEC_MSBC, hfp_connection->remote_codecs_nr, hfp_connection->remote_codecs)){
552             return HFP_CODEC_MSBC;
553         }
554     }
555     return HFP_CODEC_CVSD;
556 }
557 
558 /* state machines */
559 
560 static uint8_t hfp_ag_esco_s4_supported(hfp_connection_t * hfp_connection){
561     return (hfp_connection->remote_supported_features & (1<<HFP_HFSF_ESCO_S4)) &&  (hfp_ag_supported_features & (1 << HFP_AGSF_ESCO_S4));
562 }
563 
564 static int codecs_exchange_state_machine(hfp_connection_t * hfp_connection){
565     /* events ( == commands):
566         HFP_CMD_AVAILABLE_CODECS == received AT+BAC with list of codecs
567         HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP:
568             hf_trigger_codec_connection_setup == received BCC
569             ag_trigger_codec_connection_setup == received from AG to send BCS
570         HFP_CMD_HF_CONFIRMED_CODEC == received AT+BCS
571     */
572     switch (hfp_connection->codecs_state){
573         case HFP_CODECS_EXCHANGED:
574             if (hfp_connection->command == HFP_CMD_AVAILABLE_CODECS){
575                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
576                 return 1;
577             }
578             break;
579 
580         case HFP_CODECS_RECEIVED_TRIGGER_CODEC_EXCHANGE:
581             hfp_connection->command = HFP_CMD_AG_SEND_COMMON_CODEC;
582             break;
583         case HFP_CODECS_AG_RESEND_COMMON_CODEC:
584             hfp_connection->command = HFP_CMD_AG_SEND_COMMON_CODEC;
585             break;
586         default:
587             break;
588     }
589 
590     switch (hfp_connection->command){
591         case HFP_CMD_AVAILABLE_CODECS:
592             if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED){
593                 hfp_connection->codecs_state = HFP_CODECS_RECEIVED_LIST;
594                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
595                 return 1;
596             }
597 
598             switch (hfp_connection->codecs_state){
599                 case HFP_CODECS_AG_SENT_COMMON_CODEC:
600                     hfp_connection->codecs_state = HFP_CODECS_AG_RESEND_COMMON_CODEC;
601                     break;
602                 default:
603                     break;
604             }
605             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
606             return 1;
607 
608         case HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP:
609             hfp_connection->codecs_state = HFP_CODECS_RECEIVED_TRIGGER_CODEC_EXCHANGE;
610             hfp_connection->establish_audio_connection = 1;
611             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
612             return 1;
613 
614         case HFP_CMD_AG_SEND_COMMON_CODEC:
615             hfp_connection->codecs_state = HFP_CODECS_AG_SENT_COMMON_CODEC;
616             hfp_connection->suggested_codec = hfp_ag_suggest_codec(hfp_connection);
617             hfp_ag_send_suggest_codec_cmd(hfp_connection->rfcomm_cid, hfp_connection->suggested_codec);
618             return 1;
619 
620         case HFP_CMD_HF_CONFIRMED_CODEC:
621             if (hfp_connection->codec_confirmed != hfp_connection->suggested_codec){
622                 hfp_connection->codecs_state = HFP_CODECS_ERROR;
623                 hfp_ag_send_error(hfp_connection->rfcomm_cid);
624                 return 1;
625             }
626             hfp_connection->negotiated_codec = hfp_connection->codec_confirmed;
627             hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
628             log_info("hfp: codec confirmed: %s", (hfp_connection->negotiated_codec == HFP_CODEC_MSBC) ? "mSBC" : "CVSD");
629             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
630             // now, pick link settings
631             hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
632 #ifdef ENABLE_CC256X_ASSISTED_HFP
633             hfp_cc256x_prepare_for_sco(hfp_connection);
634 #endif
635             return 1;
636         default:
637             break;
638     }
639     return 0;
640 }
641 
642 static void hfp_ag_slc_established(hfp_connection_t * hfp_connection){
643     hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
644     hfp_emit_slc_connection_event(hfp_connection, 0, hfp_connection->acl_handle, hfp_connection->remote_addr);
645 
646     // if active call exist, set per-hfp_connection state active, too (when audio is on)
647     if (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT){
648         hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
649     }
650     // if AG is ringing, also start ringing on the HF
651     if (hfp_gsm_call_status() == HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS){
652         switch (hfp_gsm_callsetup_status()){
653             case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
654                 hfp_ag_hf_start_ringing_incoming(hfp_connection);
655                 break;
656             case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
657                 hfp_ag_hf_start_ringing_outgoing(hfp_connection);
658                 break;
659             default:
660                 break;
661         }
662     }
663 }
664 
665 static int hfp_ag_run_for_context_service_level_connection(hfp_connection_t * hfp_connection){
666     // log_info("hfp_ag_run_for_context_service_level_connection state %u, command %u", hfp_connection->state, hfp_connection->command);
667     if (hfp_connection->state >= HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) return 0;
668     int sent = 0;
669     switch(hfp_connection->command){
670         case HFP_CMD_SUPPORTED_FEATURES:
671             switch(hfp_connection->state){
672                 case HFP_W4_EXCHANGE_SUPPORTED_FEATURES:
673                 case HFP_EXCHANGE_SUPPORTED_FEATURES:
674                     hfp_hf_drop_mSBC_if_eSCO_not_supported(hfp_ag_codecs, &hfp_ag_codecs_nr);
675                     if (has_codec_negotiation_feature(hfp_connection)){
676                         hfp_connection->state = HFP_W4_NOTIFY_ON_CODECS;
677                     } else {
678                         hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS;
679                     }
680                     hfp_ag_exchange_supported_features_cmd(hfp_connection->rfcomm_cid);
681                     return 1;
682                 default:
683                     break;
684             }
685             break;
686         case HFP_CMD_AVAILABLE_CODECS:
687             sent = codecs_exchange_state_machine(hfp_connection);
688             if (hfp_connection->codecs_state == HFP_CODECS_RECEIVED_LIST){
689                 hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS;
690             }
691             return sent;
692 
693         case HFP_CMD_RETRIEVE_AG_INDICATORS:
694             if (hfp_connection->state == HFP_W4_RETRIEVE_INDICATORS) {
695                 // HF requested AG Indicators and we did expect it
696                 hfp_connection->send_ag_indicators_segment = 0;
697                 hfp_connection->state = HFP_RETRIEVE_INDICATORS;
698                 // continue below in state switch
699             }
700             break;
701 
702         case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
703             if (hfp_connection->state != HFP_W4_RETRIEVE_INDICATORS_STATUS) break;
704             hfp_connection->state = HFP_W4_ENABLE_INDICATORS_STATUS_UPDATE;
705             hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
706             return 1;
707 
708         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
709             if (hfp_connection->state != HFP_W4_ENABLE_INDICATORS_STATUS_UPDATE) break;
710             if (has_call_waiting_and_3way_calling_feature(hfp_connection)){
711                 hfp_connection->state = HFP_W4_RETRIEVE_CAN_HOLD_CALL;
712             } else if (has_hf_indicators_feature(hfp_connection)){
713                 hfp_connection->state = HFP_W4_LIST_GENERIC_STATUS_INDICATORS;
714             } else {
715                 hfp_ag_slc_established(hfp_connection);
716             }
717             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
718             return 1;
719 
720         case HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES:
721             if (hfp_connection->state != HFP_W4_RETRIEVE_CAN_HOLD_CALL) break;
722             if (has_hf_indicators_feature(hfp_connection)){
723                 hfp_connection->state = HFP_W4_LIST_GENERIC_STATUS_INDICATORS;
724             }
725             hfp_ag_send_retrieve_can_hold_call_cmd(hfp_connection->rfcomm_cid);
726             if (!has_hf_indicators_feature(hfp_connection)){
727                 hfp_ag_slc_established(hfp_connection);
728             }
729             return 1;
730 
731         case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
732             if (hfp_connection->state != HFP_W4_LIST_GENERIC_STATUS_INDICATORS) break;
733             hfp_connection->state = HFP_W4_RETRIEVE_GENERIC_STATUS_INDICATORS;
734             hfp_ag_send_list_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
735             return 1;
736 
737         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
738             if (hfp_connection->state != HFP_W4_RETRIEVE_GENERIC_STATUS_INDICATORS) break;
739             hfp_connection->state = HFP_W4_RETRIEVE_INITITAL_STATE_GENERIC_STATUS_INDICATORS;
740             hfp_ag_send_retrieve_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
741             return 1;
742 
743         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
744             if (hfp_connection->state != HFP_W4_RETRIEVE_INITITAL_STATE_GENERIC_STATUS_INDICATORS) break;
745             hfp_ag_slc_established(hfp_connection);
746             hfp_ag_send_retrieve_initital_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
747             return 1;
748         default:
749             break;
750     }
751 
752     switch (hfp_connection->state){
753         case HFP_RETRIEVE_INDICATORS: {
754             int next_segment = hfp_ag_send_retrieve_indicators_cmd_via_generator(hfp_connection->rfcomm_cid, hfp_connection, hfp_connection->send_ag_indicators_segment);
755             int num_segments = hfp_ag_indicators_cmd_generator_num_segments(hfp_connection);
756             log_info("HFP_CMD_RETRIEVE_AG_INDICATORS next segment %u, num_segments %u", next_segment, num_segments);
757             if (next_segment < num_segments){
758                 // prepare sending of next segment
759                 hfp_connection->send_ag_indicators_segment = next_segment;
760                 log_info("HFP_CMD_RETRIEVE_AG_INDICATORS more. command %u, next seg %u", hfp_connection->command, next_segment);
761             } else {
762                 // done, go to next state
763                 hfp_connection->send_ag_indicators_segment = 0;
764                 hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS_STATUS;
765             }
766             return 1;
767         }
768         default:
769             break;
770     }
771     return 0;
772 }
773 
774 static bool hfp_ag_voice_recognition_supported(hfp_connection_t * hfp_connection, bool enhanced){
775     uint8_t ag_vra_flag = HFP_AGSF_VOICE_RECOGNITION_FUNCTION;
776     uint8_t hf_vra_flag = HFP_HFSF_VOICE_RECOGNITION_FUNCTION;
777 
778     if (enhanced){
779         ag_vra_flag = HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS;
780         hf_vra_flag = HFP_HFSF_ENHANCED_VOICE_RECOGNITION_STATUS;
781     }
782 
783     int ag = get_bit(hfp_ag_supported_features, ag_vra_flag);
784     int hf = get_bit(hfp_connection->remote_supported_features, hf_vra_flag);
785     return hf && ag;
786 }
787 
788 static uint8_t hfp_ag_can_activate_voice_recognition(hfp_connection_t * hfp_connection, bool enhanced){
789     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED || hfp_connection->state > HFP_AUDIO_CONNECTION_ESTABLISHED){
790         return ERROR_CODE_COMMAND_DISALLOWED;
791     }
792     if (!hfp_ag_voice_recognition_supported(hfp_connection, enhanced)){
793         return ERROR_CODE_COMMAND_DISALLOWED;
794     }
795     if (hfp_connection->vra_state != HFP_VRA_VOICE_RECOGNITION_OFF){
796         return ERROR_CODE_COMMAND_DISALLOWED;
797     }
798     return ERROR_CODE_SUCCESS;
799 }
800 
801 static uint8_t hfp_ag_voice_recognition_session_active(hfp_connection_t * hfp_connection, bool enhanced){
802     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED || hfp_connection->state > HFP_AUDIO_CONNECTION_ESTABLISHED){
803         return ERROR_CODE_COMMAND_DISALLOWED;
804     }
805     if (!hfp_ag_voice_recognition_supported(hfp_connection, enhanced)){
806         return ERROR_CODE_COMMAND_DISALLOWED;
807     }
808     if (hfp_connection->vra_state != HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
809         if (hfp_connection->vra_state == HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
810             return ERROR_CODE_SUCCESS;
811         }
812         return ERROR_CODE_COMMAND_DISALLOWED;
813     }
814     return ERROR_CODE_SUCCESS;
815 }
816 
817 static bool hfp_ag_can_send_enahnced_voice_recognition_message(hfp_connection_t * hfp_connection, bool enhanced){
818     if (hfp_ag_voice_recognition_session_active(hfp_connection, enhanced) == ERROR_CODE_SUCCESS){
819         int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_VOICE_RECOGNITION_TEXT);
820         int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_VOICE_RECOGNITION_TEXT);
821         return hf && ag;
822     }
823     return false;
824 }
825 
826 static bool hfp_ag_is_audio_connection_active(hfp_connection_t * hfp_connection){
827     switch (hfp_connection->state){
828         case HFP_W2_CONNECT_SCO:
829         case HFP_W4_SCO_CONNECTED:
830         case HFP_AUDIO_CONNECTION_ESTABLISHED:
831             return true;
832         default:
833             return false;
834     }
835 }
836 
837 static void hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection_t * hfp_connection, uint8_t status){
838     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
839 
840     uint8_t event[6];
841     event[0] = HCI_EVENT_HFP_META;
842     event[1] = sizeof(event) - 2;
843     event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_AG_MESSAGE_SENT;
844     little_endian_store_16(event, 3, acl_handle);
845     event[5] = status;
846     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
847 }
848 
849 
850 static void hfp_ag_emit_hf_indicator_value(hfp_connection_t * hfp_connection, uint16_t uuid, uint8_t value){
851     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
852 
853     uint8_t event[8];
854     event[0] = HCI_EVENT_HFP_META;
855     event[1] = sizeof(event) - 2;
856     event[2] = HFP_SUBEVENT_HF_INDICATOR;
857     little_endian_store_16(event, 3, acl_handle);
858     little_endian_store_16(event, 5, uuid);
859     event[7] = value;
860     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
861 }
862 
863 static void hfp_ag_emit_general_simple_event(uint8_t event_subtype){
864     if (!hfp_ag_callback) return;
865 
866     uint8_t event[5];
867     event[0] = HCI_EVENT_HFP_META;
868     event[1] = sizeof(event) - 2;
869     event[2] = event_subtype;
870     little_endian_store_16(event, 3, HCI_CON_HANDLE_INVALID);
871     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
872 }
873 
874 static int hfp_ag_voice_recognition_state_machine(hfp_connection_t * hfp_connection){
875     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) {
876         return 0;
877     }
878     int done = 0;
879     uint8_t status;
880 
881     switch (hfp_connection->command){
882         case HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION:
883             switch (hfp_connection->vra_state_requested){
884                 case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG:
885                     done = hfp_ag_send_enhanced_voice_recognition_msg_cmd(hfp_connection);
886                     if (done == 0){
887                         hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection, ERROR_CODE_UNSPECIFIED_ERROR);
888                     } else {
889                         hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection, ERROR_CODE_SUCCESS);
890                     }
891                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
892                     return done;
893 
894                 case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS:
895                     done = hfp_ag_send_enhanced_voice_recognition_state_cmd(hfp_connection);
896                     if (done == 0){
897                         hfp_emit_enhanced_voice_recognition_state_event(hfp_connection, ERROR_CODE_UNSPECIFIED_ERROR);
898                     } else {
899                         hfp_emit_enhanced_voice_recognition_state_event(hfp_connection, ERROR_CODE_SUCCESS);
900                     }
901                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
902                     return done;
903 
904                 default:
905                     done = hfp_ag_send_voice_recognition_cmd(hfp_connection, hfp_connection->ag_activate_voice_recognition_value);
906                     if (done == 0){
907                         hfp_connection->vra_state_requested = hfp_connection->vra_state;
908                         hfp_emit_voice_recognition_state_event(hfp_connection, ERROR_CODE_COMMAND_DISALLOWED);
909                         return 0;
910                     }
911                     break;
912             }
913             break;
914 
915         case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
916             // HF initiatied voice recognition, parser extracted activation value
917             switch (hfp_connection->ag_activate_voice_recognition_value){
918                 case 0:
919                     if (hfp_ag_voice_recognition_session_active(hfp_connection, hfp_connection->enhanced_voice_recognition_enabled) == ERROR_CODE_SUCCESS){
920                         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
921                         done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
922                     }
923                     break;
924 
925                 case 1:
926                     if (hfp_ag_can_activate_voice_recognition(hfp_connection, hfp_connection->enhanced_voice_recognition_enabled) == ERROR_CODE_SUCCESS){
927                         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
928                         done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
929                     }
930                     break;
931 
932                 case 2:
933                     if (hfp_ag_voice_recognition_session_active(hfp_connection, hfp_connection->enhanced_voice_recognition_enabled) == ERROR_CODE_SUCCESS){
934                         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO;
935                         done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
936                     }
937                     break;
938                 default:
939                     break;
940             }
941             if (done == 0){
942                 hfp_connection->vra_state_requested = hfp_connection->vra_state;
943                 done = hfp_ag_send_error(hfp_connection->rfcomm_cid);
944                 return 1;
945             }
946             break;
947 
948         default:
949             return 0;
950     }
951 
952     switch (hfp_connection->vra_state_requested){
953         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO:
954             if (!hfp_ag_is_audio_connection_active(hfp_connection)){
955                 status = hfp_ag_setup_audio_connection(hfp_connection);
956                 if (status != ERROR_CODE_SUCCESS){
957                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
958                     hfp_emit_voice_recognition_state_event(hfp_connection, status);
959                     return 0;
960                 }
961             }
962             hfp_connection->enhanced_voice_recognition_enabled = true;
963             hfp_connection->vra_state = HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO;
964             hfp_connection->vra_state_requested = hfp_connection->vra_state;
965             hfp_emit_enhanced_voice_recognition_hf_ready_for_audio_event(hfp_connection, ERROR_CODE_SUCCESS);
966             break;
967 
968         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF:
969             hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_OFF;
970             hfp_connection->vra_state_requested = hfp_connection->vra_state;
971 
972             // release audio connection only if it was opened after audio VR activated
973             if (hfp_ag_is_audio_connection_active(hfp_connection) && !hfp_connection->ag_audio_connection_opened_before_vra){
974                 hfp_trigger_release_audio_connection(hfp_connection);
975             }
976 
977             hfp_emit_voice_recognition_state_event(hfp_connection, ERROR_CODE_SUCCESS);
978             break;
979 
980         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED:
981             // open only if audio connection does not already exist
982             if (!hfp_ag_is_audio_connection_active(hfp_connection)){
983                 status = hfp_ag_setup_audio_connection(hfp_connection);
984                 if (status != ERROR_CODE_SUCCESS){
985                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
986                     hfp_emit_voice_recognition_state_event(hfp_connection, status);
987                     return 0;
988                 }
989             }
990 
991             hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_ACTIVATED;
992             hfp_connection->vra_state_requested = hfp_connection->vra_state;
993             hfp_emit_voice_recognition_state_event(hfp_connection, ERROR_CODE_SUCCESS);
994             break;
995 
996         default:
997             break;
998     }
999     return done;
1000 }
1001 
1002 static int hfp_ag_run_for_context_service_level_connection_queries(hfp_connection_t * hfp_connection){
1003     int sent = codecs_exchange_state_machine(hfp_connection);
1004     if (sent) return 1;
1005 
1006     switch(hfp_connection->command){
1007 
1008         case HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING:
1009             hfp_ag_send_change_in_band_ring_tone_setting_cmd(hfp_connection->rfcomm_cid);
1010             return 1;
1011         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1012             hfp_ag_send_report_network_operator_name_cmd(hfp_connection->rfcomm_cid, hfp_connection->network_operator);
1013             return 1;
1014         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1015             if (hfp_connection->network_operator.format != 0){
1016                 hfp_ag_send_error(hfp_connection->rfcomm_cid);
1017             } else {
1018                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1019             }
1020             return 1;
1021         case HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE:
1022             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1023             return 1;
1024         case HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR:
1025             if (hfp_connection->extended_audio_gateway_error){
1026                 hfp_connection->extended_audio_gateway_error = 0;
1027                 hfp_ag_send_report_extended_audio_gateway_error(hfp_connection->rfcomm_cid, hfp_connection->extended_audio_gateway_error_value);
1028                 return 1;
1029             }
1030             break;
1031         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
1032             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1033             return 1;
1034         default:
1035             break;
1036     }
1037     return 0;
1038 }
1039 
1040 static int hfp_ag_run_for_audio_connection(hfp_connection_t * hfp_connection){
1041     if ((hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) ||
1042         (hfp_connection->state > HFP_W2_DISCONNECT_SCO)) return 0;
1043 
1044     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1045 
1046     if (hfp_connection->release_audio_connection){
1047         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
1048         hfp_connection->release_audio_connection = 0;
1049         gap_disconnect(hfp_connection->sco_handle);
1050         return 1;
1051     }
1052 
1053     // accept incoming audio connection (codec negotiation is not used)
1054     if (hfp_connection->accept_sco){
1055         // notify about codec selection if not done already
1056         if (hfp_connection->negotiated_codec == 0){
1057             hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
1058         }
1059         //
1060         bool incoming_eSCO = hfp_connection->accept_sco == 2;
1061         hfp_connection->accept_sco = 0;
1062         hfp_connection->state = HFP_W4_SCO_CONNECTED;
1063         hfp_accept_synchronous_connection(hfp_connection, incoming_eSCO);
1064         return 1;
1065     }
1066 
1067     // run codecs exchange
1068     int sent = codecs_exchange_state_machine(hfp_connection);
1069     if (sent) return 1;
1070 
1071     if (hfp_connection->codecs_state != HFP_CODECS_EXCHANGED) return 0;
1072     if (hfp_connection->establish_audio_connection){
1073         hfp_connection->state = HFP_W4_SCO_CONNECTED;
1074         hfp_connection->establish_audio_connection = 0;
1075         hfp_setup_synchronous_connection(hfp_connection);
1076         return 1;
1077     }
1078     return 0;
1079 }
1080 
1081 static void hfp_ag_set_callsetup_indicator(void){
1082     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("callsetup");
1083     if (!indicator){
1084         log_error("hfp_ag_set_callsetup_indicator: callsetup indicator is missing");
1085         return;
1086     };
1087     indicator->status = hfp_gsm_callsetup_status();
1088 }
1089 
1090 static void hfp_ag_set_callheld_indicator(void){
1091     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("callheld");
1092     if (!indicator){
1093         log_error("hfp_ag_set_callheld_state: callheld indicator is missing");
1094         return;
1095     };
1096     indicator->status = hfp_gsm_callheld_status();
1097 }
1098 
1099 //
1100 // transition implementations for hfp_ag_call_state_machine
1101 //
1102 
1103 static void hfp_ag_hf_start_ringing_incoming(hfp_connection_t * hfp_connection){
1104     if (use_in_band_tone()){
1105         hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING;
1106         hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1107     } else {
1108         hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1109     }
1110 }
1111 
1112 static void hfp_ag_hf_start_ringing_outgoing(hfp_connection_t * hfp_connection){
1113     hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1114 }
1115 
1116 static void hfp_ag_hf_stop_ringing(hfp_connection_t * hfp_connection){
1117     hfp_connection->ag_ring = 0;
1118     hfp_connection->ag_send_clip = 0;
1119 }
1120 
1121 
1122 static void hfp_ag_trigger_incoming_call_during_active_one(void){
1123     btstack_linked_list_iterator_t it;
1124     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1125     while (btstack_linked_list_iterator_has_next(&it)){
1126         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1127         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1128         if (hfp_connection->call_state != HFP_CALL_ACTIVE) continue;
1129 
1130         hfp_connection->call_state = HFP_CALL_W2_SEND_CALL_WAITING;
1131         hfp_ag_run_for_context(hfp_connection);
1132     }
1133 }
1134 
1135 // trigger RING and CLIP messages on connections that are ringing
1136 static void hfp_ag_ring_timeout_handler(btstack_timer_source_t * timer){
1137     btstack_linked_list_iterator_t it;
1138     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1139     while (btstack_linked_list_iterator_has_next(&it)){
1140         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1141         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1142         switch (hfp_connection->call_state){
1143             case HFP_CALL_INCOMING_RINGING:
1144             case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1145             case HFP_CALL_OUTGOING_RINGING:
1146                 // Queue RING on this connection
1147                 hfp_connection->ag_ring = 1;
1148 
1149                 // HFP v1.8, 4.23 Calling Line Identification (CLI) Notification
1150                 // "If the calling subscriber number information is available from the network, the AG shall issue the
1151                 // +CLIP unsolicited result code just after every RING indication when the HF is alerted in an incoming call."
1152                 hfp_connection->ag_send_clip = hfp_gsm_clip_type() && hfp_connection->clip_enabled;
1153 
1154                 // trigger next message
1155                 rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1156                 break;
1157             default:
1158                 break;
1159         }
1160     }
1161 
1162     btstack_run_loop_set_timer(timer, 2000); // 2 seconds timeout
1163     btstack_run_loop_add_timer(timer);
1164 }
1165 
1166 static void hfp_ag_ring_timeout_start(void){
1167     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1168     btstack_run_loop_set_timer_handler(&hfp_ag_ring_timeout, hfp_ag_ring_timeout_handler);
1169     hfp_ag_ring_timeout_handler(&hfp_ag_ring_timeout);
1170 }
1171 
1172 static void hfp_ag_ring_timeout_stop(void){
1173     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1174 }
1175 
1176 static void hfp_ag_start_ringing(void){
1177     hfp_ag_ring_timeout_start();
1178     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_START_RINGING);
1179 }
1180 
1181 static void hfp_ag_stop_ringing(void){
1182     hfp_ag_ring_timeout_stop();
1183     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_STOP_RINGING);
1184 
1185     btstack_linked_list_iterator_t it;
1186     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1187     while (btstack_linked_list_iterator_has_next(&it)){
1188         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1189         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1190         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1191             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1192         hfp_ag_hf_stop_ringing(hfp_connection);
1193     }
1194 }
1195 
1196 static void hfp_ag_trigger_incoming_call_idle(void){
1197     int indicator_index = get_ag_indicator_index_for_name("callsetup");
1198     if (indicator_index < 0) return;
1199 
1200     // update callsetup state in connections
1201     btstack_linked_list_iterator_t it;
1202     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1203     while (btstack_linked_list_iterator_has_next(&it)){
1204         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1205         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1206         if (hfp_connection->call_state != HFP_CALL_IDLE) continue;
1207 
1208         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1209 
1210         hfp_ag_hf_start_ringing_incoming(hfp_connection);
1211 
1212         hfp_ag_run_for_context(hfp_connection);
1213     }
1214 
1215     // start local ringing - started after connection state has been updated
1216     hfp_ag_start_ringing();
1217 }
1218 
1219 static void hfp_ag_trigger_outgoing_call(void){
1220     btstack_linked_list_iterator_t it;
1221     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1222     while (btstack_linked_list_iterator_has_next(&it)){
1223         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1224         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1225         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1226         if (hfp_connection->call_state == HFP_CALL_IDLE){
1227             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1228         }
1229     }
1230 }
1231 
1232 static void hfp_ag_handle_outgoing_call_accepted(hfp_connection_t * hfp_connection){
1233     hfp_connection->call_state = HFP_CALL_OUTGOING_DIALING;
1234 
1235     // trigger callsetup to be
1236     int put_call_on_hold = hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT;
1237     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ACCEPTED, 0, 0, NULL);
1238 
1239     int indicator_index ;
1240 
1241     hfp_ag_set_callsetup_indicator();
1242     indicator_index = get_ag_indicator_index_for_name("callsetup");
1243     hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1244 
1245     // put current call on hold if active
1246     if (put_call_on_hold){
1247         log_info("AG putting current call on hold for new outgoing call");
1248         hfp_ag_set_callheld_indicator();
1249         indicator_index = get_ag_indicator_index_for_name("callheld");
1250         hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[indicator_index]);
1251     }
1252 
1253     // start audio if needed
1254     hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1255 }
1256 
1257 static void hfp_ag_transfer_indicator(const char * name){
1258     int indicator_index = get_ag_indicator_index_for_name(name);
1259     if (indicator_index < 0) return;
1260 
1261     btstack_linked_list_iterator_t it;
1262     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1263     while (btstack_linked_list_iterator_has_next(&it)){
1264         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1265         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1266         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1267         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1268         hfp_ag_run_for_context(hfp_connection);
1269     }
1270 }
1271 
1272 static void hfp_ag_transfer_callsetup_state(void){
1273     hfp_ag_transfer_indicator("callsetup");
1274 }
1275 
1276 static void hfp_ag_transfer_call_state(void){
1277     hfp_ag_transfer_indicator("call");
1278 }
1279 
1280 static void hfp_ag_transfer_callheld_state(void){
1281     hfp_ag_transfer_indicator("callheld");
1282 }
1283 
1284 static void hfp_ag_hf_accept_call(hfp_connection_t * source){
1285     int call_indicator_index = get_ag_indicator_index_for_name("call");
1286     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1287 
1288     hfp_ag_stop_ringing();
1289 
1290     btstack_linked_list_iterator_t it;
1291     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1292     while (btstack_linked_list_iterator_has_next(&it)){
1293         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1294         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1295         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1296             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1297 
1298         if (hfp_connection == source){
1299 
1300             if (use_in_band_tone()){
1301                 hfp_connection->call_state = HFP_CALL_ACTIVE;
1302             } else {
1303                 hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
1304                 hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1305             }
1306 
1307             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1308             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1309 
1310         } else {
1311             hfp_connection->call_state = HFP_CALL_IDLE;
1312         }
1313         hfp_ag_run_for_context(hfp_connection);
1314     }
1315 }
1316 
1317 static void hfp_ag_ag_accept_call(void){
1318     int call_indicator_index = get_ag_indicator_index_for_name("call");
1319     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1320 
1321     hfp_ag_stop_ringing();
1322 
1323     btstack_linked_list_iterator_t it;
1324     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1325     while (btstack_linked_list_iterator_has_next(&it)){
1326         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1327         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1328         if (hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) continue;
1329 
1330         hfp_connection->call_state = HFP_CALL_TRIGGER_AUDIO_CONNECTION;
1331 
1332         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1333         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1334 
1335         hfp_ag_run_for_context(hfp_connection);
1336         break;  // only single
1337     }
1338 }
1339 
1340 static void hfp_ag_trigger_reject_call(void){
1341     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1342 
1343     hfp_ag_stop_ringing();
1344 
1345     btstack_linked_list_iterator_t it;
1346     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1347     while (btstack_linked_list_iterator_has_next(&it)){
1348         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1349         if (connection->local_role != HFP_ROLE_AG) continue;
1350         if ((connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1351             (connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1352 
1353         connection->call_state = HFP_CALL_IDLE;
1354         connection->ag_indicators_status_update_bitmap = store_bit(connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1355 
1356         if (connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1357             connection->release_audio_connection = 1;
1358         }
1359         hfp_emit_simple_event(connection, HFP_SUBEVENT_CALL_TERMINATED);
1360         hfp_ag_run_for_context(connection);
1361         rfcomm_request_can_send_now_event(connection->rfcomm_cid);
1362     }
1363 }
1364 
1365 static void hfp_ag_trigger_terminate_call(void){
1366     int call_indicator_index = get_ag_indicator_index_for_name("call");
1367 
1368     // no ringing during call
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_IDLE) continue;
1376 
1377         hfp_connection->call_state = HFP_CALL_IDLE;
1378         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1379 
1380         if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1381             hfp_connection->release_audio_connection = 1;
1382         }
1383 
1384         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_TERMINATED);
1385         hfp_ag_run_for_context(hfp_connection);
1386         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1387     }
1388 }
1389 
1390 static void hfp_ag_set_call_indicator(void){
1391     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("call");
1392     if (!indicator){
1393         log_error("hfp_ag_set_call_state: call indicator is missing");
1394         return;
1395     };
1396     indicator->status = hfp_gsm_call_status();
1397 }
1398 
1399 static hfp_connection_t * hfp_ag_connection_for_call_state(hfp_call_state_t call_state){
1400     btstack_linked_list_iterator_t it;
1401     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1402     while (btstack_linked_list_iterator_has_next(&it)){
1403         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1404         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1405         if (hfp_connection->call_state == call_state) return hfp_connection;
1406     }
1407     return NULL;
1408 }
1409 
1410 static void hfp_ag_send_response_and_hold_state(hfp_response_and_hold_state_t state){
1411     btstack_linked_list_iterator_t it;
1412     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1413     while (btstack_linked_list_iterator_has_next(&it)){
1414         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1415         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1416         hfp_connection->send_response_and_hold_status = state + 1;
1417     }
1418 }
1419 
1420 static int call_setup_state_machine(hfp_connection_t * hfp_connection){
1421     int indicator_index;
1422     switch (hfp_connection->call_state){
1423         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1424             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1425 
1426             // we got event: audio hfp_connection established
1427             hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1428             break;
1429         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE:
1430             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1431             // we got event: audio hfp_connection established
1432             hfp_connection->call_state = HFP_CALL_ACTIVE;
1433             break;
1434         case HFP_CALL_W2_SEND_CALL_WAITING:
1435             hfp_connection->call_state = HFP_CALL_W4_CHLD;
1436             hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
1437             indicator_index = get_ag_indicator_index_for_name("callsetup");
1438             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1439             break;
1440         default:
1441             break;
1442     }
1443     return 0;
1444 }
1445 
1446 // functions extracted from hfp_ag_call_sm below
1447 static void hfp_ag_handle_reject_outgoing_call(void){
1448     hfp_connection_t * hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1449     if (!hfp_connection){
1450         log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1451         return;
1452     }
1453 
1454     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_REJECTED, 0, 0, NULL);
1455     hfp_connection->call_state = HFP_CALL_IDLE;
1456     hfp_connection->send_error = 1;
1457     hfp_ag_run_for_context(hfp_connection);
1458 }
1459 
1460 // hfp_connection is used to identify originating HF
1461 static void hfp_ag_call_sm(hfp_ag_call_event_t event, hfp_connection_t * hfp_connection){
1462     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1463     int callheld_indicator_index = get_ag_indicator_index_for_name("callheld");
1464     int call_indicator_index = get_ag_indicator_index_for_name("call");
1465 
1466     switch (event){
1467         case HFP_AG_INCOMING_CALL:
1468             switch (hfp_gsm_call_status()){
1469                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1470                     switch (hfp_gsm_callsetup_status()){
1471                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1472                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1473                             hfp_ag_set_callsetup_indicator();
1474                             hfp_ag_trigger_incoming_call_idle();
1475                             log_info("AG rings");
1476                             break;
1477                         default:
1478                             break;
1479                     }
1480                     break;
1481                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1482                     switch (hfp_gsm_callsetup_status()){
1483                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1484                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1485                             hfp_ag_set_callsetup_indicator();
1486                             hfp_ag_trigger_incoming_call_during_active_one();
1487                             log_info("AG call waiting");
1488                             break;
1489                         default:
1490                             break;
1491                     }
1492                     break;
1493                 default:
1494                     break;
1495             }
1496             break;
1497         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG:
1498             switch (hfp_gsm_call_status()){
1499                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1500                     switch (hfp_gsm_callsetup_status()){
1501                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1502                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1503                             hfp_ag_set_call_indicator();
1504                             hfp_ag_set_callsetup_indicator();
1505                             hfp_ag_ag_accept_call();
1506                             log_info("AG answers call, accept call by GSM");
1507                             break;
1508                         default:
1509                             break;
1510                     }
1511                     break;
1512                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1513                     switch (hfp_gsm_callsetup_status()){
1514                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1515                             log_info("AG: current call is placed on hold, incoming call gets active");
1516                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1517                             hfp_ag_set_callsetup_indicator();
1518                             hfp_ag_set_callheld_indicator();
1519                             hfp_ag_transfer_callsetup_state();
1520                             hfp_ag_transfer_callheld_state();
1521                             break;
1522                         default:
1523                             break;
1524                     }
1525                     break;
1526                 default:
1527                     break;
1528             }
1529             break;
1530 
1531         case HFP_AG_HELD_CALL_JOINED_BY_AG:
1532             switch (hfp_gsm_call_status()){
1533                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1534                     switch (hfp_gsm_callheld_status()){
1535                         case HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED:
1536                             log_info("AG: joining held call with active call");
1537                             hfp_gsm_handler(HFP_AG_HELD_CALL_JOINED_BY_AG, 0, 0, NULL);
1538                             hfp_ag_set_callheld_indicator();
1539                             hfp_ag_transfer_callheld_state();
1540                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1541                             break;
1542                         default:
1543                             break;
1544                     }
1545                     break;
1546                 default:
1547                     break;
1548             }
1549             break;
1550 
1551         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF:
1552             switch (hfp_gsm_call_status()){
1553                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1554                     switch (hfp_gsm_callsetup_status()){
1555                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1556                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, 0, 0, NULL);
1557                             hfp_ag_set_callsetup_indicator();
1558                             hfp_ag_set_call_indicator();
1559                             hfp_ag_hf_accept_call(hfp_connection);
1560                             hfp_connection->ok_pending = 1;
1561                             log_info("HF answers call, accept call by GSM");
1562                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1563                             break;
1564                         default:
1565                             break;
1566                     }
1567                     break;
1568                 default:
1569                     break;
1570             }
1571             break;
1572 
1573         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG:
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_INCOMING_CALL_SETUP_IN_PROGRESS:
1578                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, 0, 0, NULL);
1579                             hfp_ag_response_and_hold_active = 1;
1580                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1581                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1582                             // as with regular call
1583                             hfp_ag_set_call_indicator();
1584                             hfp_ag_set_callsetup_indicator();
1585                             hfp_ag_ag_accept_call();
1586                             log_info("AG response and hold - hold by AG");
1587                             break;
1588                         default:
1589                             break;
1590                     }
1591                     break;
1592                 default:
1593                     break;
1594             }
1595             break;
1596 
1597         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF:
1598             switch (hfp_gsm_call_status()){
1599                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1600                     switch (hfp_gsm_callsetup_status()){
1601                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1602                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, 0, 0, NULL);
1603                             hfp_ag_response_and_hold_active = 1;
1604                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1605                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1606                             // as with regular call
1607                             hfp_ag_set_call_indicator();
1608                             hfp_ag_set_callsetup_indicator();
1609                             hfp_ag_hf_accept_call(hfp_connection);
1610                             log_info("AG response and hold - hold by HF");
1611                             break;
1612                         default:
1613                             break;
1614                     }
1615                     break;
1616                 default:
1617                     break;
1618             }
1619             break;
1620 
1621         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG:
1622         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF:
1623             if (!hfp_ag_response_and_hold_active) break;
1624             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1625             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, 0, 0, NULL);
1626             hfp_ag_response_and_hold_active = 0;
1627             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED;
1628             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1629             log_info("Held Call accepted and active");
1630             break;
1631 
1632         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG:
1633         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF:
1634             if (!hfp_ag_response_and_hold_active) break;
1635             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1636             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, 0, 0, NULL);
1637             hfp_ag_response_and_hold_active = 0;
1638             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1639             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1640             // from terminate by ag
1641             hfp_ag_set_call_indicator();
1642             hfp_ag_trigger_terminate_call();
1643             break;
1644 
1645         case HFP_AG_TERMINATE_CALL_BY_HF:
1646             switch (hfp_gsm_call_status()){
1647                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1648                     switch (hfp_gsm_callsetup_status()){
1649                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1650                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1651                             hfp_ag_set_callsetup_indicator();
1652                             hfp_ag_transfer_callsetup_state();
1653                             hfp_ag_trigger_reject_call();
1654                             log_info("HF Rejected Incoming call, AG terminate call");
1655                             break;
1656                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1657                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1658                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1659                             hfp_ag_set_callsetup_indicator();
1660                             hfp_ag_transfer_callsetup_state();
1661                             log_info("AG terminate outgoing call process");
1662                             break;
1663                         default:
1664                             break;
1665                     }
1666                     break;
1667                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1668                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1669                     hfp_ag_set_callsetup_indicator();
1670                     hfp_ag_set_call_indicator();
1671                     hfp_ag_trigger_terminate_call();
1672                     log_info("AG terminate call");
1673                     break;
1674                 default:
1675                     break;
1676             }
1677             break;
1678 
1679         case HFP_AG_TERMINATE_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_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1685                             hfp_ag_set_callsetup_indicator();
1686                             hfp_ag_trigger_reject_call();
1687                             log_info("AG Rejected Incoming call, AG terminate call");
1688                             break;
1689                         default:
1690                             break;
1691                     }
1692                     break;
1693                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1694                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1695                     hfp_ag_set_callsetup_indicator();
1696                     hfp_ag_set_call_indicator();
1697                     hfp_ag_trigger_terminate_call();
1698                     log_info("AG terminate call");
1699                     break;
1700                 default:
1701                     break;
1702             }
1703             break;
1704         case HFP_AG_CALL_DROPPED:
1705             switch (hfp_gsm_call_status()){
1706                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1707                     switch (hfp_gsm_callsetup_status()){
1708                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1709                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1710                             hfp_ag_stop_ringing();
1711                             break;
1712                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1713                             log_info("Outgoing call interrupted\n");
1714                             break;
1715                         default:
1716                             break;
1717                     }
1718                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1719                     hfp_ag_set_callsetup_indicator();
1720                     hfp_ag_transfer_callsetup_state();
1721                     hfp_ag_trigger_terminate_call();
1722                     break;
1723                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1724                     if (hfp_ag_response_and_hold_active) {
1725                         hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1726                         hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1727                         hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1728                     }
1729                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1730                     hfp_ag_set_callsetup_indicator();
1731                     hfp_ag_set_call_indicator();
1732                     hfp_ag_trigger_terminate_call();
1733                     log_info("AG notify call dropped");
1734                     break;
1735                 default:
1736                     break;
1737             }
1738             break;
1739 
1740         case HFP_AG_OUTGOING_CALL_INITIATED_BY_HF:
1741             // directly reject call if number of free slots is exceeded
1742             if (!hfp_gsm_call_possible()){
1743                 hfp_connection->send_error = 1;
1744                 hfp_ag_run_for_context(hfp_connection);
1745                 break;
1746             }
1747 
1748             // note: number not used currently
1749             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, 0, 0, (const char *) &hfp_connection->line_buffer[3]);
1750 
1751             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1752 
1753             hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, (const char *) &hfp_connection->line_buffer[3]);
1754             break;
1755 
1756         case HFP_AG_OUTGOING_CALL_INITIATED_BY_AG:
1757             // directly reject call if number of free slots is exceeded
1758             if (!hfp_gsm_call_possible()) {
1759                 // TODO: no error for user
1760                 break;
1761             }
1762             switch (hfp_gsm_call_status()) {
1763                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1764                     switch (hfp_gsm_callsetup_status()) {
1765                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1766                             // note: number not used currently
1767                             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, 0, 0, "1234567");
1768                             // init call state for all connections
1769                             hfp_ag_trigger_outgoing_call();
1770                             // get first one and accept call
1771                             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1772                             if (hfp_connection) {
1773                                 hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1774                             }
1775                             break;
1776                         default:
1777                             // TODO: no error for user
1778                             break;
1779                     }
1780                     break;
1781                 default:
1782                     // TODO: no error for user
1783                     break;
1784             }
1785             break;
1786         case HFP_AG_OUTGOING_REDIAL_INITIATED:{
1787             // directly reject call if number of free slots is exceeded
1788             if (!hfp_gsm_call_possible()){
1789                 hfp_connection->send_error = 1;
1790                 hfp_ag_run_for_context(hfp_connection);
1791                 break;
1792             }
1793 
1794             hfp_gsm_handler(HFP_AG_OUTGOING_REDIAL_INITIATED, 0, 0, NULL);
1795             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1796 
1797             log_info("Redial last number");
1798             char * last_dialed_number = hfp_gsm_last_dialed_number();
1799 
1800             if (strlen(last_dialed_number) > 0){
1801                 log_info("Last number exists: accept call");
1802                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, last_dialed_number);
1803             } else {
1804                 log_info("log_infoLast number missing: reject call");
1805                 hfp_ag_handle_reject_outgoing_call();
1806             }
1807             break;
1808         }
1809         case HFP_AG_OUTGOING_CALL_REJECTED:
1810             hfp_ag_handle_reject_outgoing_call();
1811             break;
1812 
1813         case HFP_AG_OUTGOING_CALL_ACCEPTED:{
1814             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1815             if (!hfp_connection){
1816                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1817                 break;
1818             }
1819 
1820             hfp_connection->ok_pending = 1;
1821             hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1822             break;
1823         }
1824         case HFP_AG_OUTGOING_CALL_RINGING:
1825             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1826             if (!hfp_connection){
1827                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in dialing state");
1828                 break;
1829             }
1830 
1831             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_RINGING, 0, 0, NULL);
1832             hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1833             hfp_ag_set_callsetup_indicator();
1834             hfp_ag_transfer_callsetup_state();
1835             hfp_ag_hf_start_ringing_outgoing(hfp_connection);
1836             break;
1837 
1838         case HFP_AG_OUTGOING_CALL_ESTABLISHED:{
1839             // get outgoing call
1840             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_RINGING);
1841             if (!hfp_connection){
1842                 hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1843             }
1844             if (!hfp_connection){
1845                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection");
1846                 break;
1847             }
1848 
1849             bool callheld_status_call_on_hold_and_no_active_calls = hfp_gsm_callheld_status() == HFP_CALLHELD_STATUS_CALL_ON_HOLD_AND_NO_ACTIVE_CALLS;
1850             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ESTABLISHED, 0, 0, NULL);
1851             hfp_connection->call_state = HFP_CALL_ACTIVE;
1852             hfp_ag_set_callsetup_indicator();
1853             hfp_ag_set_call_indicator();
1854             hfp_ag_transfer_call_state();
1855             hfp_ag_transfer_callsetup_state();
1856             if (callheld_status_call_on_hold_and_no_active_calls){
1857                 hfp_ag_set_callheld_indicator();
1858                 hfp_ag_transfer_callheld_state();
1859             }
1860             hfp_ag_hf_stop_ringing(hfp_connection);
1861             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1862             break;
1863         }
1864 
1865         case HFP_AG_CALL_HOLD_USER_BUSY:
1866             hfp_gsm_handler(HFP_AG_CALL_HOLD_USER_BUSY, 0, 0, NULL);
1867             hfp_ag_set_callsetup_indicator();
1868             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1869             hfp_connection->call_state = HFP_CALL_ACTIVE;
1870             log_info("AG: Call Waiting, User Busy");
1871             break;
1872 
1873         case HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1874             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1875             int call_held = hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD;
1876 
1877             // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
1878             if (call_held || call_setup_in_progress){
1879                 hfp_gsm_handler(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index,
1880                                 0, NULL);
1881 
1882             }
1883 
1884             if (call_setup_in_progress){
1885                 log_info("AG: Call Dropped, Accept new call");
1886                 hfp_ag_set_callsetup_indicator();
1887                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1888             } else {
1889                 log_info("AG: Call Dropped, Resume held call");
1890             }
1891             if (call_held){
1892                 hfp_ag_set_callheld_indicator();
1893                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1894             }
1895 
1896             hfp_connection->call_state = HFP_CALL_ACTIVE;
1897             break;
1898         }
1899 
1900         case HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1901             // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
1902             // only update if callsetup changed
1903             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1904             hfp_gsm_handler(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index, 0,
1905                             NULL);
1906 
1907             if (call_setup_in_progress){
1908                 log_info("AG: Call on Hold, Accept new call");
1909                 hfp_ag_set_callsetup_indicator();
1910                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1911             } else {
1912                 log_info("AG: Swap calls");
1913             }
1914 
1915             hfp_ag_set_callheld_indicator();
1916             // hfp_ag_set_callheld_state(HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED);
1917             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1918             hfp_connection->call_state = HFP_CALL_ACTIVE;
1919             break;
1920         }
1921 
1922         case HFP_AG_CALL_HOLD_ADD_HELD_CALL:
1923             // Adds a held call to the conversation.
1924             if (hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD){
1925                 log_info("AG: Join 3-way-call");
1926                 hfp_gsm_handler(HFP_AG_CALL_HOLD_ADD_HELD_CALL, 0, 0, NULL);
1927                 hfp_ag_set_callheld_indicator();
1928                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1929                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1930             }
1931             hfp_connection->call_state = HFP_CALL_ACTIVE;
1932             break;
1933         case HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS:
1934             // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer)
1935             hfp_gsm_handler(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, 0, 0, NULL);
1936             log_info("AG: Transfer call -> Connect two calls and disconnect");
1937             hfp_ag_set_call_indicator();
1938             hfp_ag_set_callheld_indicator();
1939             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1940             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1941             hfp_connection->call_state = HFP_CALL_IDLE;
1942             break;
1943 
1944         default:
1945             break;
1946     }
1947 
1948 
1949 }
1950 
1951 
1952 static void hfp_ag_send_call_status(hfp_connection_t * hfp_connection, int call_index){
1953     hfp_gsm_call_t * active_call = hfp_gsm_call(call_index);
1954     if (!active_call) return;
1955 
1956     int idx = active_call->index;
1957     hfp_enhanced_call_dir_t dir = active_call->direction;
1958     hfp_enhanced_call_status_t status = active_call->enhanced_status;
1959     hfp_enhanced_call_mode_t mode = active_call->mode;
1960     hfp_enhanced_call_mpty_t mpty = active_call->mpty;
1961     uint8_t type = active_call->clip_type;
1962     char * number = active_call->clip_number;
1963 
1964     char buffer[100];
1965     // TODO: check length of a buffer, to fit the MTU
1966     int offset = snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d,%d,%d,%d", HFP_LIST_CURRENT_CALLS, idx, dir, status, mode, mpty);
1967     if (number){
1968         offset += snprintf(buffer+offset, sizeof(buffer)-offset-3, ", \"%s\",%u", number, type);
1969     }
1970     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n");
1971     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,
1972        mode, mpty, type, number);
1973     send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
1974 }
1975 
1976 // sends pending command, returns if command was sent
1977 static int hfp_ag_send_commands(hfp_connection_t *hfp_connection){
1978     if (hfp_connection->send_status_of_current_calls){
1979         hfp_connection->ok_pending = 0;
1980         if (hfp_connection->next_call_index < hfp_gsm_get_number_of_calls()){
1981             hfp_connection->next_call_index++;
1982             hfp_ag_send_call_status(hfp_connection, hfp_connection->next_call_index);
1983             return 1;
1984         } else {
1985             // 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
1986             hfp_connection->next_call_index = 0;
1987             hfp_connection->ok_pending = 1;
1988             hfp_connection->send_status_of_current_calls = 0;
1989         }
1990     }
1991 
1992     if (hfp_connection->ag_notify_incoming_call_waiting){
1993         hfp_connection->ag_notify_incoming_call_waiting = 0;
1994         hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
1995         return 1;
1996     }
1997 
1998     if (hfp_connection->command == HFP_CMD_UNKNOWN){
1999         hfp_connection->ok_pending = 0;
2000         hfp_connection->send_error = 0;
2001         hfp_connection->command = HFP_CMD_NONE;
2002         hfp_ag_send_error(hfp_connection->rfcomm_cid);
2003         return 1;
2004     }
2005 
2006     if (hfp_connection->send_error){
2007         hfp_connection->send_error = 0;
2008         hfp_connection->command = HFP_CMD_NONE;
2009         hfp_ag_send_error(hfp_connection->rfcomm_cid);
2010         return 1;
2011     }
2012 
2013     // note: before update AG indicators and ok_pending
2014     if (hfp_connection->send_response_and_hold_status){
2015         int status = hfp_connection->send_response_and_hold_status - 1;
2016         hfp_connection->send_response_and_hold_status = 0;
2017         hfp_ag_send_set_response_and_hold(hfp_connection->rfcomm_cid, status);
2018         return 1;
2019     }
2020 
2021     if (hfp_connection->ok_pending){
2022         hfp_connection->ok_pending = 0;
2023         hfp_connection->command = HFP_CMD_NONE;
2024         hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2025         return 1;
2026     }
2027 
2028     // update AG indicators
2029     if (hfp_connection->ag_indicators_status_update_bitmap){
2030         int i;
2031         for (i=0;i<hfp_connection->ag_indicators_nr;i++){
2032             if (get_bit(hfp_connection->ag_indicators_status_update_bitmap, i)){
2033                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, i, 0);
2034                 if (!hfp_connection->enable_status_update_for_ag_indicators) {
2035                     log_info("+CMER:3,0,0,0 - not sending update for '%s'", hfp_ag_indicators[i].name);
2036                     break;
2037                 }
2038                 hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[i]);
2039                 return 1;
2040             }
2041         }
2042     }
2043 
2044     if (hfp_connection->ag_send_no_carrier){
2045         hfp_connection->ag_send_no_carrier = false;
2046         hfp_ag_send_no_carrier(hfp_connection->rfcomm_cid);
2047         return 1;
2048     }
2049 
2050     if (hfp_connection->ag_ring){
2051         hfp_connection->ag_ring = 0;
2052         hfp_connection->command = HFP_CMD_NONE;
2053         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_RING);
2054         hfp_ag_send_ring(hfp_connection->rfcomm_cid);
2055         return 1;
2056     }
2057 
2058     if (hfp_connection->ag_send_clip){
2059         hfp_connection->ag_send_clip = 0;
2060         hfp_connection->command = HFP_CMD_NONE;
2061         hfp_ag_send_clip(hfp_connection->rfcomm_cid);
2062         return 1;
2063     }
2064 
2065     if (hfp_connection->send_phone_number_for_voice_tag){
2066         hfp_connection->send_phone_number_for_voice_tag = 0;
2067         hfp_connection->command = HFP_CMD_NONE;
2068         hfp_connection->ok_pending = 1;
2069         hfp_ag_send_phone_number_for_voice_tag_cmd(hfp_connection->rfcomm_cid);
2070         return 1;
2071     }
2072 
2073     if (hfp_connection->send_subscriber_number){
2074         if (hfp_connection->next_subscriber_number_to_send < hfp_ag_subscriber_numbers_count){
2075             hfp_phone_number_t phone = hfp_ag_subscriber_numbers[hfp_connection->next_subscriber_number_to_send++];
2076             hfp_send_subscriber_number_cmd(hfp_connection->rfcomm_cid, phone.type, phone.number);
2077         } else {
2078             hfp_connection->send_subscriber_number = 0;
2079             hfp_connection->next_subscriber_number_to_send = 0;
2080             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2081         }
2082         hfp_connection->command = HFP_CMD_NONE;
2083         return 1;
2084     }
2085 
2086     if (hfp_connection->send_microphone_gain){
2087         hfp_connection->send_microphone_gain = 0;
2088         hfp_connection->command = HFP_CMD_NONE;
2089         hfp_ag_send_set_microphone_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->microphone_gain);
2090         return 1;
2091     }
2092 
2093     if (hfp_connection->send_speaker_gain){
2094         hfp_connection->send_speaker_gain = 0;
2095         hfp_connection->command = HFP_CMD_NONE;
2096         hfp_ag_send_set_speaker_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->speaker_gain);
2097         return 1;
2098     }
2099 
2100     if (hfp_connection->send_ag_status_indicators){
2101         hfp_connection->send_ag_status_indicators = 0;
2102         hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
2103         return 1;
2104     }
2105 
2106     return 0;
2107 }
2108 
2109 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection){
2110 
2111 	btstack_assert(hfp_connection != NULL);
2112 	btstack_assert(hfp_connection->local_role == HFP_ROLE_AG);
2113 
2114 	// during SDP query, RFCOMM CID is not set
2115 	if (hfp_connection->rfcomm_cid == 0) return;
2116 
2117     // assert command could be sent
2118     if (hci_can_send_command_packet_now() == 0) return;
2119 
2120     if ((hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) && hfp_connection->release_audio_connection){
2121         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
2122         hfp_connection->release_audio_connection = 0;
2123         gap_disconnect(hfp_connection->sco_handle);
2124         return;
2125     }
2126 
2127 #ifdef ENABLE_CC256X_ASSISTED_HFP
2128     // WBS Disassociate
2129     if (hfp_connection->cc256x_send_wbs_disassociate){
2130         hfp_connection->cc256x_send_wbs_disassociate = false;
2131         hci_send_cmd(&hci_ti_wbs_disassociate);
2132         return;
2133     }
2134     // Write Codec Config
2135     if (hfp_connection->cc256x_send_write_codec_config){
2136         hfp_connection->cc256x_send_write_codec_config = false;
2137         hfp_cc256x_write_codec_config(hfp_connection);
2138         return;
2139     }
2140     // WBS Associate
2141     if (hfp_connection->cc256x_send_wbs_associate){
2142         hfp_connection->cc256x_send_wbs_associate = false;
2143         hci_send_cmd(&hci_ti_wbs_associate, hfp_connection->acl_handle);
2144         return;
2145     }
2146 #endif
2147 #ifdef ENABLE_BCM_PCM_WBS
2148     // Enable WBS
2149     if (hfp_connection->bcm_send_enable_wbs){
2150         hfp_connection->bcm_send_enable_wbs = false;
2151         hci_send_cmd(&hci_bcm_enable_wbs, 1, 2);
2152         return;
2153     }
2154     // Write I2S/PCM params
2155     if (hfp_connection->bcm_send_write_i2spcm_interface_param){
2156         hfp_connection->bcm_send_write_i2spcm_interface_param = false;
2157         hfp_bcm_write_i2spcm_interface_param(hfp_connection);
2158         return;
2159     }
2160     // Disable WBS
2161     if (hfp_connection->bcm_send_disable_wbs){
2162         hfp_connection->bcm_send_disable_wbs = false;
2163         hci_send_cmd(&hci_bcm_enable_wbs, 0, 2);
2164         return;
2165     }
2166 #endif
2167 #if defined (ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
2168     if (hfp_connection->state == HFP_W4_WBS_SHUTDOWN){
2169         hfp_finalize_connection_context(hfp_connection);
2170         return;
2171     }
2172 #endif
2173 
2174     if (!rfcomm_can_send_packet_now(hfp_connection->rfcomm_cid)) {
2175         log_info("hfp_ag_run_for_context: request can send for 0x%02x", hfp_connection->rfcomm_cid);
2176         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2177         return;
2178     }
2179 
2180     int cmd_sent = hfp_ag_send_commands(hfp_connection);
2181 
2182     if (!cmd_sent){
2183         cmd_sent = hfp_ag_run_for_context_service_level_connection(hfp_connection);
2184     }
2185 
2186     if (!cmd_sent){
2187         cmd_sent = hfp_ag_run_for_context_service_level_connection_queries(hfp_connection);
2188     }
2189 
2190     if (!cmd_sent){
2191         cmd_sent = call_setup_state_machine(hfp_connection);
2192     }
2193 
2194     // trigger codec exchange (must be before hfp_ag_run_for_audio_connection)
2195     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && hfp_connection->trigger_codec_exchange){
2196         switch (hfp_connection->codecs_state){
2197             case HFP_CODECS_IDLE:
2198             case HFP_CODECS_RECEIVED_LIST:
2199             case HFP_CODECS_AG_RESEND_COMMON_CODEC:
2200             case HFP_CODECS_ERROR:
2201                 hfp_connection->trigger_codec_exchange = 0;
2202                 hfp_connection->command = HFP_CMD_AG_SEND_COMMON_CODEC;
2203                 break;
2204             default:
2205                 break;
2206         }
2207     }
2208 
2209     if (!cmd_sent){
2210         cmd_sent = hfp_ag_run_for_audio_connection(hfp_connection);
2211     }
2212 
2213     if (!cmd_sent){
2214         cmd_sent = hfp_ag_voice_recognition_state_machine(hfp_connection);
2215     }
2216 
2217     // disconnect
2218     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && (hfp_connection->state == HFP_W2_DISCONNECT_RFCOMM)){
2219         hfp_connection->state = HFP_W4_RFCOMM_DISCONNECTED;
2220         rfcomm_disconnect(hfp_connection->rfcomm_cid);
2221     }
2222 
2223     if (cmd_sent){
2224         hfp_connection->command = HFP_CMD_NONE;
2225         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2226     }
2227 }
2228 
2229 static int hfp_parser_is_end_of_line(uint8_t byte){
2230     return (byte == '\n') || (byte == '\r');
2231 }
2232 
2233 static void hfp_ag_handle_rfcomm_data(hfp_connection_t * hfp_connection, uint8_t *packet, uint16_t size){
2234     // assertion: size >= 1 as rfcomm.c does not deliver empty packets
2235     if (size < 1) return;
2236     uint8_t status = ERROR_CODE_SUCCESS;
2237 
2238     hfp_log_rfcomm_message("HFP_AG_RX", packet, size);
2239 #ifdef ENABLE_HFP_AT_MESSAGES
2240     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_RECEIVED, (char *) packet);
2241 #endif
2242 
2243     // process messages byte-wise
2244     int pos;
2245     for (pos = 0; pos < size ; pos++){
2246         hfp_parse(hfp_connection, packet[pos], 0);
2247 
2248         // parse until end of line
2249         if (!hfp_parser_is_end_of_line(packet[pos])) continue;
2250 
2251         hfp_generic_status_indicator_t * indicator;
2252         switch(hfp_connection->command){
2253             case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
2254                 // dealt with in hfp_ag_voice_recognition_state_machine
2255                 break;
2256             case HFP_CMD_RESPONSE_AND_HOLD_QUERY:
2257                 if (hfp_ag_response_and_hold_active){
2258                     hfp_connection->send_response_and_hold_status = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD + 1;
2259                 }
2260                 hfp_connection->ok_pending = 1;
2261                 break;
2262             case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
2263                 switch(hfp_connection->ag_response_and_hold_action){
2264                     case HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD:
2265                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, hfp_connection);
2266                         break;
2267                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED:
2268                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF, hfp_connection);
2269                         break;
2270                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED:
2271                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF, hfp_connection);
2272                         break;
2273                     default:
2274                         break;
2275                 }
2276                 hfp_connection->ok_pending = 1;
2277                 break;
2278             case HFP_CMD_HF_INDICATOR_STATUS:
2279                 hfp_connection->command = HFP_CMD_NONE;
2280 
2281                 if (hfp_connection->parser_indicator_index < hfp_ag_generic_status_indicators_nr){
2282                     indicator = &hfp_ag_generic_status_indicators[hfp_connection->parser_indicator_index];
2283                     switch (indicator->uuid){
2284                         case HFP_HF_INDICATOR_UUID_ENHANCED_SAFETY:
2285                             if (hfp_connection->parser_indicator_value > 1) {
2286                                 hfp_connection->send_error = 1;
2287                                 break;
2288                             }
2289                             hfp_connection->ok_pending = 1;
2290                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2291                             break;
2292                         case HFP_HF_INDICATOR_UUID_BATTERY_LEVEL:
2293                             if (hfp_connection->parser_indicator_value > 100){
2294                                 hfp_connection->send_error = 1;
2295                                 break;
2296                             }
2297                             hfp_connection->ok_pending = 1;
2298                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2299                             break;
2300                         default:
2301                             hfp_connection->send_error = 1;
2302                             break;
2303                     }
2304                 } else {
2305                     hfp_connection->send_error = 1;
2306                 }
2307                 break;
2308             case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
2309                 // expected by SLC state machine
2310                 if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) break;
2311                 hfp_connection->send_ag_indicators_segment = 0;
2312                 hfp_connection->send_ag_status_indicators = 1;
2313                 break;
2314             case HFP_CMD_LIST_CURRENT_CALLS:
2315                 hfp_connection->command = HFP_CMD_NONE;
2316                 hfp_connection->next_call_index = 0;
2317                 hfp_connection->send_status_of_current_calls = 1;
2318                 break;
2319             case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
2320                 if (hfp_ag_subscriber_numbers_count == 0){
2321                     hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2322                     break;
2323                 }
2324                 hfp_connection->next_subscriber_number_to_send = 0;
2325                 hfp_connection->send_subscriber_number = 1;
2326                 break;
2327             case HFP_CMD_TRANSMIT_DTMF_CODES:
2328             {
2329                 hfp_connection->command = HFP_CMD_NONE;
2330                 char buffer[2];
2331                 buffer[0] = (char) hfp_connection->ag_dtmf_code;
2332                 buffer[1] = 0;
2333                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_TRANSMIT_DTMF_CODES, buffer);
2334                 break;
2335             }
2336             case HFP_CMD_HF_REQUEST_PHONE_NUMBER:
2337                 hfp_connection->command = HFP_CMD_NONE;
2338                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_ATTACH_NUMBER_TO_VOICE_TAG);
2339                 break;
2340             case HFP_CMD_TURN_OFF_EC_AND_NR:
2341                 hfp_connection->command = HFP_CMD_NONE;
2342 
2343                 if (get_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION)){
2344                     hfp_connection->ok_pending = 1;
2345                     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION, hfp_connection->ag_echo_and_noise_reduction);
2346                     status = ERROR_CODE_SUCCESS;
2347                 } else {
2348                     hfp_connection->send_error = 1;
2349                     status = ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2350                 }
2351                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_ECHO_CANCELING_AND_NOISE_REDUCTION_DEACTIVATE, status);
2352                 break;
2353             case HFP_CMD_CALL_ANSWERED:
2354                 hfp_connection->command = HFP_CMD_NONE;
2355                 log_info("HFP: ATA");
2356                 hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, hfp_connection);
2357                 break;
2358             case HFP_CMD_HANG_UP_CALL:
2359                 hfp_connection->command = HFP_CMD_NONE;
2360                 hfp_connection->ok_pending = 1;
2361                 hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_HF, hfp_connection);
2362                 break;
2363             case HFP_CMD_CALL_HOLD: {
2364                 hfp_connection->command = HFP_CMD_NONE;
2365                 hfp_connection->ok_pending = 1;
2366 
2367                 switch (hfp_connection->ag_call_hold_action){
2368                     case 0:
2369                         // Releases all held calls or sets User Determined User Busy (UDUB) for a waiting call.
2370                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_USER_BUSY, hfp_connection);
2371                         break;
2372                     case 1:
2373                         // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
2374                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2375                         // waiting call (i.e., not to the held call) in conflicting situation.
2376                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2377                         break;
2378                     case 2:
2379                         // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
2380                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2381                         // waiting call (i.e., not to the held call) in conflicting situation.
2382                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2383                         break;
2384                     case 3:
2385                         // Adds a held call to the conversation.
2386                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_ADD_HELD_CALL, hfp_connection);
2387                         break;
2388                     case 4:
2389                         // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer).
2390                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, hfp_connection);
2391                         break;
2392                     default:
2393                         break;
2394                 }
2395 				hfp_connection->call_index = 0;
2396                 break;
2397             }
2398             case HFP_CMD_CALL_PHONE_NUMBER:
2399                 hfp_connection->command = HFP_CMD_NONE;
2400                 hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, hfp_connection);
2401                 break;
2402             case HFP_CMD_REDIAL_LAST_NUMBER:
2403                 hfp_connection->command = HFP_CMD_NONE;
2404                 hfp_ag_call_sm(HFP_AG_OUTGOING_REDIAL_INITIATED, hfp_connection);
2405                 break;
2406             case HFP_CMD_ENABLE_CLIP:
2407                 hfp_connection->command = HFP_CMD_NONE;
2408                 log_info("hfp: clip set, now: %u", hfp_connection->clip_enabled);
2409                 hfp_connection->ok_pending = 1;
2410                 break;
2411             case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
2412                 hfp_connection->command = HFP_CMD_NONE;
2413                 log_info("hfp: call waiting notification set, now: %u", hfp_connection->call_waiting_notification_enabled);
2414                 hfp_connection->ok_pending = 1;
2415                 break;
2416             case HFP_CMD_SET_SPEAKER_GAIN:
2417                 hfp_connection->command = HFP_CMD_NONE;
2418                 hfp_connection->ok_pending = 1;
2419                 log_info("HF speaker gain = %u", hfp_connection->speaker_gain);
2420                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_SPEAKER_VOLUME, hfp_connection->speaker_gain);
2421                 break;
2422             case HFP_CMD_SET_MICROPHONE_GAIN:
2423                 hfp_connection->command = HFP_CMD_NONE;
2424                 hfp_connection->ok_pending = 1;
2425                 log_info("HF microphone gain = %u", hfp_connection->microphone_gain);
2426                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_MICROPHONE_VOLUME, hfp_connection->microphone_gain);
2427                 break;
2428             default:
2429                 break;
2430         }
2431     }
2432 }
2433 
2434 static void hfp_ag_run(void){
2435     btstack_linked_list_iterator_t it;
2436     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2437     while (btstack_linked_list_iterator_has_next(&it)){
2438         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2439         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2440         hfp_ag_run_for_context(hfp_connection);
2441     }
2442 }
2443 
2444 static void hfp_ag_rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2445     hfp_connection_t * hfp_connection = NULL;
2446     switch (packet_type){
2447         case RFCOMM_DATA_PACKET:
2448             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(channel);
2449             btstack_assert(hfp_connection != NULL);
2450 
2451             hfp_ag_handle_rfcomm_data(hfp_connection, packet, size);
2452             hfp_ag_run_for_context(hfp_connection);
2453             return;
2454         case HCI_EVENT_PACKET:
2455             if (packet[0] == RFCOMM_EVENT_CAN_SEND_NOW){
2456                 uint16_t rfcomm_cid = rfcomm_event_can_send_now_get_rfcomm_cid(packet);
2457                 hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
2458                 btstack_assert(hfp_connection != NULL);
2459 
2460                 hfp_ag_run_for_context(hfp_connection);
2461                 return;
2462             }
2463             hfp_handle_rfcomm_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2464             break;
2465         default:
2466             break;
2467     }
2468 
2469     hfp_ag_run();
2470 }
2471 
2472 static void hfp_ag_hci_event_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2473     hfp_handle_hci_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2474     hfp_ag_run();
2475 }
2476 
2477 void hfp_ag_init_codecs(int codecs_nr, const uint8_t * codecs){
2478     if (codecs_nr > HFP_MAX_NUM_CODECS){
2479         log_error("hfp_init: codecs_nr (%d) > HFP_MAX_NUM_CODECS (%d)", codecs_nr, HFP_MAX_NUM_CODECS);
2480         return;
2481     }
2482     int i;
2483     hfp_ag_codecs_nr = codecs_nr;
2484     for (i=0; i < codecs_nr; i++){
2485         hfp_ag_codecs[i] = codecs[i];
2486     }
2487 }
2488 
2489 void hfp_ag_init_supported_features(uint32_t supported_features){
2490     hfp_ag_supported_features = supported_features;
2491 }
2492 
2493 void hfp_ag_init_ag_indicators(int ag_indicators_nr, const hfp_ag_indicator_t * ag_indicators){
2494     hfp_ag_indicators_nr = ag_indicators_nr;
2495     (void)memcpy(hfp_ag_indicators, ag_indicators,
2496                  ag_indicators_nr * sizeof(hfp_ag_indicator_t));
2497 }
2498 
2499 void hfp_ag_init_hf_indicators(int hf_indicators_nr, const hfp_generic_status_indicator_t * hf_indicators){
2500     if (hf_indicators_nr > HFP_MAX_NUM_INDICATORS) return;
2501     hfp_ag_generic_status_indicators_nr = hf_indicators_nr;
2502     (void)memcpy(hfp_ag_generic_status_indicators, hf_indicators,
2503                  hf_indicators_nr * sizeof(hfp_generic_status_indicator_t));
2504 }
2505 
2506 void hfp_ag_init_call_hold_services(int call_hold_services_nr, const char * call_hold_services[]){
2507     hfp_ag_call_hold_services_nr = call_hold_services_nr;
2508     (void)memcpy(hfp_ag_call_hold_services, call_hold_services,
2509                  call_hold_services_nr * sizeof(char *));
2510 }
2511 
2512 
2513 void hfp_ag_init(uint16_t rfcomm_channel_nr){
2514 
2515     hfp_init();
2516     hfp_ag_call_hold_services_nr = 0;
2517     hfp_ag_response_and_hold_active = 0;
2518     hfp_ag_indicators_nr = 0;
2519     hfp_ag_codecs_nr = 0;
2520     hfp_ag_supported_features = HFP_DEFAULT_AG_SUPPORTED_FEATURES;
2521     hfp_ag_subscriber_numbers = NULL;
2522     hfp_ag_subscriber_numbers_count = 0;
2523 
2524     hfp_ag_hci_event_callback_registration.callback = &hfp_ag_hci_event_packet_handler;
2525     hci_add_event_handler(&hfp_ag_hci_event_callback_registration);
2526 
2527     rfcomm_register_service(&hfp_ag_rfcomm_packet_handler, rfcomm_channel_nr, 0xffff);
2528 
2529     // used to set packet handler for outgoing rfcomm connections - could be handled by emitting an event to us
2530     hfp_set_ag_rfcomm_packet_handler(&hfp_ag_rfcomm_packet_handler);
2531 
2532     hfp_gsm_init();
2533 }
2534 
2535 void hfp_ag_deinit(void){
2536     hfp_deinit();
2537     hfp_gsm_deinit();
2538 
2539     hfp_ag_callback = NULL;
2540     hfp_ag_supported_features = 0;
2541     hfp_ag_codecs_nr = 0;
2542     hfp_ag_indicators_nr = 0;
2543     hfp_ag_call_hold_services_nr = 0;
2544     (void) memset(&hfp_ag_call_hold_services, 0, sizeof(hfp_ag_call_hold_services));
2545     hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
2546     (void) memset(&hfp_ag_response_and_hold_state, 0, sizeof(hfp_response_and_hold_state_t));
2547     hfp_ag_subscriber_numbers = NULL;
2548     (void) memset(&hfp_ag_hci_event_callback_registration, 0, sizeof(btstack_packet_callback_registration_t));
2549 }
2550 
2551 uint8_t hfp_ag_establish_service_level_connection(bd_addr_t bd_addr){
2552     return hfp_establish_service_level_connection(bd_addr, BLUETOOTH_SERVICE_CLASS_HANDSFREE, HFP_ROLE_AG);
2553 }
2554 
2555 uint8_t hfp_ag_release_service_level_connection(hci_con_handle_t acl_handle){
2556     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2557     if (!hfp_connection){
2558         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2559     }
2560 
2561     hfp_trigger_release_service_level_connection(hfp_connection);
2562     hfp_ag_run_for_context(hfp_connection);
2563     return ERROR_CODE_SUCCESS;
2564 }
2565 
2566 uint8_t hfp_ag_report_extended_audio_gateway_error_result_code(hci_con_handle_t acl_handle, hfp_cme_error_t error){
2567     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2568     if (!hfp_connection){
2569         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2570     }
2571 
2572     hfp_connection->extended_audio_gateway_error = 0;
2573     if (!hfp_connection->enable_extended_audio_gateway_error_report){
2574         return ERROR_CODE_COMMAND_DISALLOWED;
2575     }
2576 
2577     hfp_connection->extended_audio_gateway_error = error;
2578     hfp_ag_run_for_context(hfp_connection);
2579     return ERROR_CODE_SUCCESS;
2580 }
2581 
2582 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection){
2583     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
2584         return ERROR_CODE_COMMAND_DISALLOWED;
2585     }
2586     if (hfp_connection->state >= HFP_W2_DISCONNECT_SCO){
2587         return ERROR_CODE_COMMAND_DISALLOWED;
2588     }
2589 
2590     hfp_connection->establish_audio_connection = 1;
2591     if (!has_codec_negotiation_feature(hfp_connection)){
2592         log_info("hfp_ag_establish_audio_connection - no codec negotiation feature, using CVSD");
2593         hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
2594         hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
2595         // now, pick link settings
2596         hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
2597 #ifdef ENABLE_CC256X_ASSISTED_HFP
2598         hfp_cc256x_prepare_for_sco(hfp_connection);
2599 #endif
2600         return ERROR_CODE_SUCCESS;
2601     }
2602 
2603     uint8_t i;
2604     bool codec_was_in_use = false;
2605     bool better_codec_can_be_used = false;
2606 
2607     for (i = 0; i<hfp_connection->remote_codecs_nr; i++){
2608         if (hfp_connection->negotiated_codec == hfp_connection->remote_codecs[i]){
2609             codec_was_in_use = true;
2610         } else if (hfp_connection->negotiated_codec < hfp_connection->remote_codecs[i]){
2611             better_codec_can_be_used = true;
2612         }
2613     }
2614 
2615     if (!codec_was_in_use || better_codec_can_be_used){
2616         hfp_connection->trigger_codec_exchange = 1;
2617         hfp_connection->codecs_state = HFP_CODECS_IDLE;
2618     }
2619     return ERROR_CODE_SUCCESS;
2620 }
2621 
2622 uint8_t hfp_ag_establish_audio_connection(hci_con_handle_t acl_handle){
2623     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2624     if (!hfp_connection){
2625         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2626     }
2627     uint8_t status = hfp_ag_setup_audio_connection(hfp_connection);
2628     if (status != ERROR_CODE_SUCCESS){
2629         return status;
2630     }
2631     hfp_ag_run_for_context(hfp_connection);
2632     return ERROR_CODE_SUCCESS;
2633 }
2634 
2635 uint8_t hfp_ag_release_audio_connection(hci_con_handle_t acl_handle){
2636     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2637     if (!hfp_connection){
2638         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2639     }
2640 
2641     if (hfp_connection->vra_state == HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
2642         return ERROR_CODE_COMMAND_DISALLOWED;
2643     }
2644 
2645     uint8_t status = hfp_trigger_release_audio_connection(hfp_connection);
2646     if (status == ERROR_CODE_SUCCESS){
2647         hfp_ag_run_for_context(hfp_connection);
2648     }
2649     return status;
2650 }
2651 
2652 /**
2653  * @brief Enable in-band ring tone
2654  */
2655 void hfp_ag_set_use_in_band_ring_tone(int use_in_band_ring_tone){
2656     if (get_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE) == use_in_band_ring_tone){
2657         return;
2658     }
2659 
2660     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE, use_in_band_ring_tone);
2661 
2662     btstack_linked_list_iterator_t it;
2663     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2664     while (btstack_linked_list_iterator_has_next(&it)){
2665         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2666         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2667         hfp_connection->command = HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING;
2668         hfp_ag_run_for_context(hfp_connection);
2669     }
2670 }
2671 
2672 /**
2673  * @brief Called from GSM
2674  */
2675 void hfp_ag_incoming_call(void){
2676     hfp_ag_call_sm(HFP_AG_INCOMING_CALL, NULL);
2677 }
2678 
2679 void hfp_ag_outgoing_call_initiated(const char * number) {
2680     UNUSED(number);
2681     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, NULL);
2682 }
2683 
2684 /**
2685  * @brief number is stored.
2686  */
2687 void hfp_ag_set_clip(uint8_t type, const char * number){
2688     hfp_gsm_handler(HFP_AG_SET_CLIP, 0, type, number);
2689 }
2690 
2691 void hfp_ag_call_dropped(void){
2692     hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2693 }
2694 
2695 // call from AG UI
2696 void hfp_ag_answer_incoming_call(void){
2697     hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, NULL);
2698 }
2699 
2700 void hfp_ag_join_held_call(void){
2701     hfp_ag_call_sm(HFP_AG_HELD_CALL_JOINED_BY_AG, NULL);
2702 }
2703 
2704 void hfp_ag_terminate_call(void){
2705     hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_AG, NULL);
2706 }
2707 
2708 void hfp_ag_outgoing_call_ringing(void){
2709     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_RINGING, NULL);
2710 }
2711 
2712 void hfp_ag_outgoing_call_established(void){
2713     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ESTABLISHED, NULL);
2714 }
2715 
2716 void hfp_ag_outgoing_call_rejected(void){
2717     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_REJECTED, NULL);
2718 }
2719 
2720 void hfp_ag_outgoing_call_accepted(void){
2721     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ACCEPTED, NULL);
2722 }
2723 
2724 void hfp_ag_hold_incoming_call(void){
2725     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, NULL);
2726 }
2727 
2728 void hfp_ag_accept_held_incoming_call(void) {
2729     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, NULL);
2730 }
2731 
2732 void hfp_ag_reject_held_incoming_call(void){
2733     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, NULL);
2734 }
2735 
2736 static void hfp_ag_set_ag_indicator(const char * name, int value){
2737     int indicator_index = get_ag_indicator_index_for_name(name);
2738     if (indicator_index < 0) return;
2739     hfp_ag_indicators[indicator_index].status = value;
2740 
2741     btstack_linked_list_iterator_t it;
2742     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2743     while (btstack_linked_list_iterator_has_next(&it)){
2744         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2745         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2746         if (!hfp_connection->ag_indicators[indicator_index].enabled) {
2747             log_info("Requested AG indicator '%s' update to %u, but it is not enabled", hfp_ag_indicators[indicator_index].name, value);
2748             continue;
2749         }
2750         log_info("AG indicator '%s' changed to %u, request transfer status", hfp_ag_indicators[indicator_index].name, value);
2751         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
2752         hfp_ag_run_for_context(hfp_connection);
2753     }
2754 }
2755 
2756 uint8_t hfp_ag_set_registration_status(int registration_status){
2757     if ((registration_status < 0) || (registration_status > 1)){
2758         return ERROR_CODE_COMMAND_DISALLOWED;
2759     }
2760 
2761     if ( (registration_status == 0) && (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT)){
2762 
2763         // if network goes away wihle a call is active:
2764         // - the  call gets dropped
2765         // - we send NO CARRIER
2766         // NOTE: the CALL=0 has to be sent before NO CARRIER
2767 
2768         hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2769 
2770         btstack_linked_list_iterator_t it;
2771         btstack_linked_list_iterator_init(&it, hfp_get_connections());
2772         while (btstack_linked_list_iterator_has_next(&it)){
2773             hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2774             hfp_connection->ag_send_no_carrier = true;
2775         }
2776     }
2777     hfp_ag_set_ag_indicator("service", registration_status);
2778     return ERROR_CODE_SUCCESS;
2779 }
2780 
2781 uint8_t hfp_ag_set_signal_strength(int signal_strength){
2782     if ((signal_strength < 0) || (signal_strength > 5)){
2783         return ERROR_CODE_COMMAND_DISALLOWED;
2784     }
2785 
2786     hfp_ag_set_ag_indicator("signal", signal_strength);
2787     return ERROR_CODE_SUCCESS;
2788 }
2789 
2790 uint8_t hfp_ag_set_roaming_status(int roaming_status){
2791     if ((roaming_status < 0) || (roaming_status > 1)){
2792         return ERROR_CODE_COMMAND_DISALLOWED;
2793     }
2794 
2795     hfp_ag_set_ag_indicator("roam", roaming_status);
2796     return ERROR_CODE_SUCCESS;
2797 }
2798 
2799 uint8_t hfp_ag_set_battery_level(int battery_level){
2800     if ((battery_level < 0) || (battery_level > 5)){
2801         return ERROR_CODE_COMMAND_DISALLOWED;
2802     }
2803     hfp_ag_set_ag_indicator("battchg", battery_level);
2804     return ERROR_CODE_SUCCESS;
2805 }
2806 
2807 static uint8_t activate_voice_recognition(hci_con_handle_t acl_handle, bool enhanced){
2808     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2809     if (!hfp_connection){
2810         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2811     }
2812 
2813     uint8_t status = hfp_ag_can_activate_voice_recognition(hfp_connection, enhanced);
2814     if (status == ERROR_CODE_SUCCESS){
2815         hfp_connection->ag_activate_voice_recognition_value = 1;
2816         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
2817         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2818         hfp_connection->enhanced_voice_recognition_enabled = enhanced;
2819         hfp_connection->ag_audio_connection_opened_before_vra = hfp_ag_is_audio_connection_active(hfp_connection);
2820         hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2821         hfp_ag_run_for_context(hfp_connection);
2822     }
2823     return status;
2824 }
2825 
2826 static uint8_t deactivate_voice_recognition(hci_con_handle_t acl_handle, bool enhanced){
2827     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2828     if (!hfp_connection){
2829         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2830     }
2831     uint8_t status = hfp_ag_voice_recognition_session_active(hfp_connection, enhanced);
2832     if (status == ERROR_CODE_SUCCESS){
2833         hfp_connection->ag_activate_voice_recognition_value = 0;
2834         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
2835         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2836         hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2837         hfp_ag_run_for_context(hfp_connection);
2838     }
2839     return status;
2840 }
2841 
2842 uint8_t hfp_ag_activate_voice_recognition(hci_con_handle_t acl_handle){
2843     return activate_voice_recognition(acl_handle, false);
2844 }
2845 
2846 uint8_t hfp_ag_activate_enhanced_voice_recognition(hci_con_handle_t acl_handle){
2847     return activate_voice_recognition(acl_handle, true);
2848 }
2849 
2850 uint8_t hfp_ag_deactivate_voice_recognition(hci_con_handle_t acl_handle){
2851     return deactivate_voice_recognition(acl_handle, false);
2852 }
2853 
2854 uint8_t hfp_ag_deactivate_enhanced_voice_recognition(hci_con_handle_t acl_handle){
2855     return deactivate_voice_recognition(acl_handle, true);
2856 }
2857 
2858 static uint8_t hfp_ag_enhanced_voice_recognition_send_state(hci_con_handle_t acl_handle, hfp_voice_recognition_state_t state){
2859     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2860     if (!hfp_connection){
2861         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2862     }
2863 
2864     uint8_t status = hfp_ag_voice_recognition_session_active(hfp_connection, true);
2865     if (status == ERROR_CODE_SUCCESS){
2866         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2867         hfp_connection->ag_vra_state = state;
2868         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS;
2869         hfp_ag_run_for_context(hfp_connection);
2870     }
2871     return status;
2872 }
2873 
2874 uint8_t hfp_ag_enhanced_voice_recognition_report_sending_audio(hci_con_handle_t acl_handle){
2875     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_STARTING_SOUND);
2876 }
2877 uint8_t hfp_ag_enhanced_voice_recognition_report_ready_for_audio(hci_con_handle_t acl_handle){
2878     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_READY_TO_ACCEPT_AUDIO_INPUT);
2879 }
2880 uint8_t hfp_ag_enhanced_voice_recognition_report_processing_input(hci_con_handle_t acl_handle){
2881     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_PROCESSING_AUDIO_INPUT);
2882 }
2883 
2884 
2885 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){
2886     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2887     if (!hfp_connection){
2888         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2889     }
2890 
2891     uint8_t status = hfp_ag_can_send_enahnced_voice_recognition_message(hfp_connection, true);
2892     if (status == ERROR_CODE_SUCCESS){
2893         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2894         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG;
2895         hfp_connection->ag_msg = msg;
2896         hfp_connection->ag_vra_state = state;
2897         hfp_ag_run_for_context(hfp_connection);
2898     }
2899     return status;
2900 }
2901 
2902 
2903 uint8_t hfp_ag_set_microphone_gain(hci_con_handle_t acl_handle, int gain){
2904     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2905     if (!hfp_connection){
2906         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2907     }
2908 
2909     if ((gain < 0) || (gain > 15)){
2910         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
2911         return ERROR_CODE_COMMAND_DISALLOWED;
2912     }
2913 
2914     if (hfp_connection->microphone_gain != gain){
2915         hfp_connection->command = HFP_CMD_SET_MICROPHONE_GAIN;
2916         hfp_connection->microphone_gain = gain;
2917         hfp_connection->send_microphone_gain = 1;
2918     }
2919     hfp_ag_run_for_context(hfp_connection);
2920     return ERROR_CODE_SUCCESS;
2921 }
2922 
2923 uint8_t hfp_ag_set_speaker_gain(hci_con_handle_t acl_handle, int gain){
2924     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2925     if (!hfp_connection){
2926         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2927     }
2928 
2929     if ((gain < 0) || (gain > 15)){
2930         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
2931         return ERROR_CODE_COMMAND_DISALLOWED;
2932     }
2933 
2934     if (hfp_connection->speaker_gain != gain){
2935         hfp_connection->speaker_gain = gain;
2936         hfp_connection->send_speaker_gain = 1;
2937     }
2938     hfp_ag_run_for_context(hfp_connection);
2939     return ERROR_CODE_SUCCESS;
2940 }
2941 
2942 uint8_t hfp_ag_send_phone_number_for_voice_tag(hci_con_handle_t acl_handle, const char * number){
2943     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2944     if (!hfp_connection){
2945         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2946     }
2947 
2948     hfp_ag_set_clip(0, number);
2949     hfp_connection->send_phone_number_for_voice_tag = 1;
2950     return ERROR_CODE_SUCCESS;
2951 }
2952 
2953 uint8_t hfp_ag_reject_phone_number_for_voice_tag(hci_con_handle_t acl_handle){
2954     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2955     if (!hfp_connection){
2956         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2957     }
2958 
2959     hfp_connection->send_error = 1;
2960     return ERROR_CODE_SUCCESS;
2961 }
2962 
2963 uint8_t hfp_ag_send_dtmf_code_done(hci_con_handle_t acl_handle){
2964     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2965     if (!hfp_connection){
2966         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2967     }
2968 
2969     hfp_connection->ok_pending = 1;
2970     return ERROR_CODE_SUCCESS;
2971 }
2972 
2973 void hfp_ag_set_subcriber_number_information(hfp_phone_number_t * numbers, int numbers_count){
2974     hfp_ag_subscriber_numbers = numbers;
2975     hfp_ag_subscriber_numbers_count = numbers_count;
2976 }
2977 
2978 void hfp_ag_clear_last_dialed_number(void){
2979     hfp_gsm_clear_last_dialed_number();
2980 }
2981 
2982 void hfp_ag_set_last_dialed_number(const char * number){
2983     hfp_gsm_set_last_dialed_number(number);
2984 }
2985 
2986 uint8_t hfp_ag_notify_incoming_call_waiting(hci_con_handle_t acl_handle){
2987     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2988     if (!hfp_connection){
2989         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2990     }
2991 
2992     if (!hfp_connection->call_waiting_notification_enabled){
2993         return ERROR_CODE_COMMAND_DISALLOWED;
2994     }
2995 
2996     hfp_connection->ag_notify_incoming_call_waiting = 1;
2997     hfp_ag_run_for_context(hfp_connection);
2998     return ERROR_CODE_SUCCESS;
2999 }
3000 
3001 void hfp_ag_create_sdp_record(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr, const char * name, uint8_t ability_to_reject_call, uint16_t supported_features, int wide_band_speech){
3002 	if (!name){
3003 		name = hfp_ag_default_service_name;
3004 	}
3005 	hfp_create_sdp_record(service, service_record_handle, BLUETOOTH_SERVICE_CLASS_HANDSFREE_AUDIO_GATEWAY, rfcomm_channel_nr, name);
3006 
3007 	/*
3008 	 * 0x01 – Ability to reject a call
3009 	 * 0x00 – No ability to reject a call
3010 	 */
3011 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0301);    // Hands-Free Profile - Network
3012 	de_add_number(service, DE_UINT, DE_SIZE_8, ability_to_reject_call);
3013 
3014 	// Construct SupportedFeatures for SDP bitmap:
3015 	//
3016 	// "The values of the “SupportedFeatures” bitmap given in Table 5.4 shall be the same as the values
3017 	//  of the Bits 0 to 4 of the unsolicited result code +BRSF"
3018 	//
3019 	// Wide band speech (bit 5) requires Codec negotiation
3020 	//
3021 	uint16_t sdp_features = supported_features & 0x1f;
3022 	if ( (wide_band_speech == 1) && (supported_features & (1 << HFP_AGSF_CODEC_NEGOTIATION))){
3023 		sdp_features |= 1 << 5;
3024 	}
3025 
3026     if (supported_features & (1 << HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS)){
3027         sdp_features |= 1 << 6;
3028     }
3029 
3030     if (supported_features & (1 << HFP_AGSF_VOICE_RECOGNITION_TEXT)){
3031         sdp_features |= 1 << 7;
3032     }
3033 
3034 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);    // Hands-Free Profile - SupportedFeatures
3035 	de_add_number(service, DE_UINT, DE_SIZE_16, sdp_features);
3036 }
3037 
3038 void hfp_ag_register_packet_handler(btstack_packet_handler_t callback){
3039 	btstack_assert(callback != NULL);
3040 
3041 	hfp_ag_callback = callback;
3042 	hfp_set_ag_callback(callback);
3043 }
3044