xref: /btstack/src/classic/hfp_ag.c (revision b0ab732ebdd4053aea2dc77b7a345d52285e484e)
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 static void hfp_ag_trigger_ring_and_clip(void) {
1136     btstack_linked_list_iterator_t it;
1137     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1138     while (btstack_linked_list_iterator_has_next(&it)){
1139         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1140         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1141         switch (hfp_connection->call_state){
1142             case HFP_CALL_INCOMING_RINGING:
1143             case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1144             case HFP_CALL_OUTGOING_RINGING:
1145                 // Queue RING on this connection
1146                 hfp_connection->ag_ring = 1;
1147 
1148                 // HFP v1.8, 4.23 Calling Line Identification (CLI) Notification
1149                 // "If the calling subscriber number information is available from the network, the AG shall issue the
1150                 // +CLIP unsolicited result code just after every RING indication when the HF is alerted in an incoming call."
1151                 hfp_connection->ag_send_clip = hfp_gsm_clip_type() && hfp_connection->clip_enabled;
1152 
1153                 // trigger next message
1154                 rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1155                 break;
1156             default:
1157                 break;
1158         }
1159     }
1160 }
1161 
1162 // trigger RING and CLIP messages on connections that are ringing
1163 static void hfp_ag_ring_timeout_handler(btstack_timer_source_t * timer){
1164     hfp_ag_trigger_ring_and_clip();
1165 
1166     btstack_run_loop_set_timer(timer, HFP_RING_PERIOD_MS); // 2 seconds timeout
1167     btstack_run_loop_add_timer(timer);
1168 }
1169 
1170 static void hfp_ag_ring_timeout_stop(void){
1171     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1172 }
1173 
1174 static void hfp_ag_start_ringing(void){
1175     // setup ring timer
1176     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1177     btstack_run_loop_set_timer_handler(&hfp_ag_ring_timeout, hfp_ag_ring_timeout_handler);
1178     btstack_run_loop_set_timer(&hfp_ag_ring_timeout, HFP_RING_PERIOD_MS); // 2 seconds timeout
1179     btstack_run_loop_add_timer(&hfp_ag_ring_timeout);
1180 
1181     // emit start ringing
1182     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_START_RINGING);
1183 
1184     // send initial RING + CLIP
1185     hfp_ag_trigger_ring_and_clip();
1186 }
1187 
1188 static void hfp_ag_stop_ringing(void){
1189     hfp_ag_ring_timeout_stop();
1190     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_STOP_RINGING);
1191 
1192     btstack_linked_list_iterator_t it;
1193     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1194     while (btstack_linked_list_iterator_has_next(&it)){
1195         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1196         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1197         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1198             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1199         hfp_ag_hf_stop_ringing(hfp_connection);
1200     }
1201 }
1202 
1203 static void hfp_ag_trigger_incoming_call_idle(void){
1204     int indicator_index = get_ag_indicator_index_for_name("callsetup");
1205     if (indicator_index < 0) return;
1206 
1207     // update callsetup state in connections
1208     btstack_linked_list_iterator_t it;
1209     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1210     while (btstack_linked_list_iterator_has_next(&it)){
1211         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1212         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1213         if (hfp_connection->call_state != HFP_CALL_IDLE) continue;
1214 
1215         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1216 
1217         hfp_ag_hf_start_ringing_incoming(hfp_connection);
1218 
1219         hfp_ag_run_for_context(hfp_connection);
1220     }
1221 
1222     // start local ringing - started after connection state has been updated
1223     hfp_ag_start_ringing();
1224 }
1225 
1226 static void hfp_ag_trigger_outgoing_call(void){
1227     btstack_linked_list_iterator_t it;
1228     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1229     while (btstack_linked_list_iterator_has_next(&it)){
1230         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1231         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1232         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1233         if (hfp_connection->call_state == HFP_CALL_IDLE){
1234             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1235         }
1236     }
1237 }
1238 
1239 static void hfp_ag_handle_outgoing_call_accepted(hfp_connection_t * hfp_connection){
1240     hfp_connection->call_state = HFP_CALL_OUTGOING_DIALING;
1241 
1242     // trigger callsetup to be
1243     int put_call_on_hold = hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT;
1244     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ACCEPTED, 0, 0, NULL);
1245 
1246     int indicator_index ;
1247 
1248     hfp_ag_set_callsetup_indicator();
1249     indicator_index = get_ag_indicator_index_for_name("callsetup");
1250     hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1251 
1252     // put current call on hold if active
1253     if (put_call_on_hold){
1254         log_info("AG putting current call on hold for new outgoing call");
1255         hfp_ag_set_callheld_indicator();
1256         indicator_index = get_ag_indicator_index_for_name("callheld");
1257         hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[indicator_index]);
1258     }
1259 
1260     // start audio if needed
1261     hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1262 }
1263 
1264 static void hfp_ag_transfer_indicator(const char * name){
1265     int indicator_index = get_ag_indicator_index_for_name(name);
1266     if (indicator_index < 0) return;
1267 
1268     btstack_linked_list_iterator_t it;
1269     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1270     while (btstack_linked_list_iterator_has_next(&it)){
1271         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1272         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1273         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1274         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1275         hfp_ag_run_for_context(hfp_connection);
1276     }
1277 }
1278 
1279 static void hfp_ag_transfer_callsetup_state(void){
1280     hfp_ag_transfer_indicator("callsetup");
1281 }
1282 
1283 static void hfp_ag_transfer_call_state(void){
1284     hfp_ag_transfer_indicator("call");
1285 }
1286 
1287 static void hfp_ag_transfer_callheld_state(void){
1288     hfp_ag_transfer_indicator("callheld");
1289 }
1290 
1291 static void hfp_ag_hf_accept_call(hfp_connection_t * source){
1292     int call_indicator_index = get_ag_indicator_index_for_name("call");
1293     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1294 
1295     hfp_ag_stop_ringing();
1296 
1297     btstack_linked_list_iterator_t it;
1298     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1299     while (btstack_linked_list_iterator_has_next(&it)){
1300         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1301         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1302         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1303             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1304 
1305         if (hfp_connection == source){
1306 
1307             if (use_in_band_tone()){
1308                 hfp_connection->call_state = HFP_CALL_ACTIVE;
1309             } else {
1310                 hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
1311                 hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1312             }
1313 
1314             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1315             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1316 
1317         } else {
1318             hfp_connection->call_state = HFP_CALL_IDLE;
1319         }
1320         hfp_ag_run_for_context(hfp_connection);
1321     }
1322 }
1323 
1324 static void hfp_ag_ag_accept_call(void){
1325     int call_indicator_index = get_ag_indicator_index_for_name("call");
1326     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1327 
1328     hfp_ag_stop_ringing();
1329 
1330     btstack_linked_list_iterator_t it;
1331     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1332     while (btstack_linked_list_iterator_has_next(&it)){
1333         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1334         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1335         if (hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) continue;
1336 
1337         hfp_connection->call_state = HFP_CALL_TRIGGER_AUDIO_CONNECTION;
1338 
1339         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1340         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1341 
1342         hfp_ag_run_for_context(hfp_connection);
1343         break;  // only single
1344     }
1345 }
1346 
1347 static void hfp_ag_trigger_reject_call(void){
1348     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1349 
1350     hfp_ag_stop_ringing();
1351 
1352     btstack_linked_list_iterator_t it;
1353     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1354     while (btstack_linked_list_iterator_has_next(&it)){
1355         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1356         if (connection->local_role != HFP_ROLE_AG) continue;
1357         if ((connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1358             (connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1359 
1360         connection->call_state = HFP_CALL_IDLE;
1361         connection->ag_indicators_status_update_bitmap = store_bit(connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1362 
1363         if (connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1364             connection->release_audio_connection = 1;
1365         }
1366         hfp_emit_simple_event(connection, HFP_SUBEVENT_CALL_TERMINATED);
1367         hfp_ag_run_for_context(connection);
1368         rfcomm_request_can_send_now_event(connection->rfcomm_cid);
1369     }
1370 }
1371 
1372 static void hfp_ag_trigger_terminate_call(void){
1373     int call_indicator_index = get_ag_indicator_index_for_name("call");
1374 
1375     // no ringing during call
1376 
1377     btstack_linked_list_iterator_t it;
1378     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1379     while (btstack_linked_list_iterator_has_next(&it)){
1380         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1381         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1382         if (hfp_connection->call_state == HFP_CALL_IDLE) continue;
1383 
1384         hfp_connection->call_state = HFP_CALL_IDLE;
1385         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1386 
1387         if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1388             hfp_connection->release_audio_connection = 1;
1389         }
1390 
1391         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_TERMINATED);
1392         hfp_ag_run_for_context(hfp_connection);
1393         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1394     }
1395 }
1396 
1397 static void hfp_ag_set_call_indicator(void){
1398     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("call");
1399     if (!indicator){
1400         log_error("hfp_ag_set_call_state: call indicator is missing");
1401         return;
1402     };
1403     indicator->status = hfp_gsm_call_status();
1404 }
1405 
1406 static hfp_connection_t * hfp_ag_connection_for_call_state(hfp_call_state_t call_state){
1407     btstack_linked_list_iterator_t it;
1408     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1409     while (btstack_linked_list_iterator_has_next(&it)){
1410         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1411         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1412         if (hfp_connection->call_state == call_state) return hfp_connection;
1413     }
1414     return NULL;
1415 }
1416 
1417 static void hfp_ag_send_response_and_hold_state(hfp_response_and_hold_state_t state){
1418     btstack_linked_list_iterator_t it;
1419     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1420     while (btstack_linked_list_iterator_has_next(&it)){
1421         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1422         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1423         hfp_connection->send_response_and_hold_status = state + 1;
1424     }
1425 }
1426 
1427 static int call_setup_state_machine(hfp_connection_t * hfp_connection){
1428     int indicator_index;
1429     switch (hfp_connection->call_state){
1430         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1431             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1432 
1433             // we got event: audio hfp_connection established
1434             hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1435             break;
1436         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE:
1437             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1438             // we got event: audio hfp_connection established
1439             hfp_connection->call_state = HFP_CALL_ACTIVE;
1440             break;
1441         case HFP_CALL_W2_SEND_CALL_WAITING:
1442             hfp_connection->call_state = HFP_CALL_W4_CHLD;
1443             hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
1444             indicator_index = get_ag_indicator_index_for_name("callsetup");
1445             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1446             break;
1447         default:
1448             break;
1449     }
1450     return 0;
1451 }
1452 
1453 // functions extracted from hfp_ag_call_sm below
1454 static void hfp_ag_handle_reject_outgoing_call(void){
1455     hfp_connection_t * hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1456     if (!hfp_connection){
1457         log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1458         return;
1459     }
1460 
1461     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_REJECTED, 0, 0, NULL);
1462     hfp_connection->call_state = HFP_CALL_IDLE;
1463     hfp_connection->send_error = 1;
1464     hfp_ag_run_for_context(hfp_connection);
1465 }
1466 
1467 // hfp_connection is used to identify originating HF
1468 static void hfp_ag_call_sm(hfp_ag_call_event_t event, hfp_connection_t * hfp_connection){
1469     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1470     int callheld_indicator_index = get_ag_indicator_index_for_name("callheld");
1471     int call_indicator_index = get_ag_indicator_index_for_name("call");
1472 
1473     switch (event){
1474         case HFP_AG_INCOMING_CALL:
1475             switch (hfp_gsm_call_status()){
1476                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1477                     switch (hfp_gsm_callsetup_status()){
1478                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1479                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1480                             hfp_ag_set_callsetup_indicator();
1481                             hfp_ag_trigger_incoming_call_idle();
1482                             log_info("AG rings");
1483                             break;
1484                         default:
1485                             break;
1486                     }
1487                     break;
1488                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1489                     switch (hfp_gsm_callsetup_status()){
1490                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1491                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1492                             hfp_ag_set_callsetup_indicator();
1493                             hfp_ag_trigger_incoming_call_during_active_one();
1494                             log_info("AG call waiting");
1495                             break;
1496                         default:
1497                             break;
1498                     }
1499                     break;
1500                 default:
1501                     break;
1502             }
1503             break;
1504         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG:
1505             switch (hfp_gsm_call_status()){
1506                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1507                     switch (hfp_gsm_callsetup_status()){
1508                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1509                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1510                             hfp_ag_set_call_indicator();
1511                             hfp_ag_set_callsetup_indicator();
1512                             hfp_ag_ag_accept_call();
1513                             log_info("AG answers call, accept call by GSM");
1514                             break;
1515                         default:
1516                             break;
1517                     }
1518                     break;
1519                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1520                     switch (hfp_gsm_callsetup_status()){
1521                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1522                             log_info("AG: current call is placed on hold, incoming call gets active");
1523                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1524                             hfp_ag_set_callsetup_indicator();
1525                             hfp_ag_set_callheld_indicator();
1526                             hfp_ag_transfer_callsetup_state();
1527                             hfp_ag_transfer_callheld_state();
1528                             break;
1529                         default:
1530                             break;
1531                     }
1532                     break;
1533                 default:
1534                     break;
1535             }
1536             break;
1537 
1538         case HFP_AG_HELD_CALL_JOINED_BY_AG:
1539             switch (hfp_gsm_call_status()){
1540                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1541                     switch (hfp_gsm_callheld_status()){
1542                         case HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED:
1543                             log_info("AG: joining held call with active call");
1544                             hfp_gsm_handler(HFP_AG_HELD_CALL_JOINED_BY_AG, 0, 0, NULL);
1545                             hfp_ag_set_callheld_indicator();
1546                             hfp_ag_transfer_callheld_state();
1547                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1548                             break;
1549                         default:
1550                             break;
1551                     }
1552                     break;
1553                 default:
1554                     break;
1555             }
1556             break;
1557 
1558         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF:
1559             switch (hfp_gsm_call_status()){
1560                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1561                     switch (hfp_gsm_callsetup_status()){
1562                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1563                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, 0, 0, NULL);
1564                             hfp_ag_set_callsetup_indicator();
1565                             hfp_ag_set_call_indicator();
1566                             hfp_ag_hf_accept_call(hfp_connection);
1567                             hfp_connection->ok_pending = 1;
1568                             log_info("HF answers call, accept call by GSM");
1569                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1570                             break;
1571                         default:
1572                             break;
1573                     }
1574                     break;
1575                 default:
1576                     break;
1577             }
1578             break;
1579 
1580         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG:
1581             switch (hfp_gsm_call_status()){
1582                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1583                     switch (hfp_gsm_callsetup_status()){
1584                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1585                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, 0, 0, NULL);
1586                             hfp_ag_response_and_hold_active = 1;
1587                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1588                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1589                             // as with regular call
1590                             hfp_ag_set_call_indicator();
1591                             hfp_ag_set_callsetup_indicator();
1592                             hfp_ag_ag_accept_call();
1593                             log_info("AG response and hold - hold by AG");
1594                             break;
1595                         default:
1596                             break;
1597                     }
1598                     break;
1599                 default:
1600                     break;
1601             }
1602             break;
1603 
1604         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF:
1605             switch (hfp_gsm_call_status()){
1606                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1607                     switch (hfp_gsm_callsetup_status()){
1608                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1609                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, 0, 0, NULL);
1610                             hfp_ag_response_and_hold_active = 1;
1611                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1612                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1613                             // as with regular call
1614                             hfp_ag_set_call_indicator();
1615                             hfp_ag_set_callsetup_indicator();
1616                             hfp_ag_hf_accept_call(hfp_connection);
1617                             log_info("AG response and hold - hold by HF");
1618                             break;
1619                         default:
1620                             break;
1621                     }
1622                     break;
1623                 default:
1624                     break;
1625             }
1626             break;
1627 
1628         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG:
1629         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF:
1630             if (!hfp_ag_response_and_hold_active) break;
1631             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1632             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, 0, 0, NULL);
1633             hfp_ag_response_and_hold_active = 0;
1634             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED;
1635             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1636             log_info("Held Call accepted and active");
1637             break;
1638 
1639         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG:
1640         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF:
1641             if (!hfp_ag_response_and_hold_active) break;
1642             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1643             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, 0, 0, NULL);
1644             hfp_ag_response_and_hold_active = 0;
1645             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1646             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1647             // from terminate by ag
1648             hfp_ag_set_call_indicator();
1649             hfp_ag_trigger_terminate_call();
1650             break;
1651 
1652         case HFP_AG_TERMINATE_CALL_BY_HF:
1653             switch (hfp_gsm_call_status()){
1654                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1655                     switch (hfp_gsm_callsetup_status()){
1656                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1657                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1658                             hfp_ag_set_callsetup_indicator();
1659                             hfp_ag_transfer_callsetup_state();
1660                             hfp_ag_trigger_reject_call();
1661                             log_info("HF Rejected Incoming call, AG terminate call");
1662                             break;
1663                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1664                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1665                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1666                             hfp_ag_set_callsetup_indicator();
1667                             hfp_ag_transfer_callsetup_state();
1668                             log_info("AG terminate outgoing call process");
1669                             break;
1670                         default:
1671                             break;
1672                     }
1673                     break;
1674                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1675                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1676                     hfp_ag_set_callsetup_indicator();
1677                     hfp_ag_set_call_indicator();
1678                     hfp_ag_trigger_terminate_call();
1679                     log_info("AG terminate call");
1680                     break;
1681                 default:
1682                     break;
1683             }
1684             break;
1685 
1686         case HFP_AG_TERMINATE_CALL_BY_AG:
1687             switch (hfp_gsm_call_status()){
1688                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1689                     switch (hfp_gsm_callsetup_status()){
1690                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1691                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1692                             hfp_ag_set_callsetup_indicator();
1693                             hfp_ag_trigger_reject_call();
1694                             log_info("AG Rejected Incoming call, AG terminate call");
1695                             break;
1696                         default:
1697                             break;
1698                     }
1699                     break;
1700                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1701                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1702                     hfp_ag_set_callsetup_indicator();
1703                     hfp_ag_set_call_indicator();
1704                     hfp_ag_trigger_terminate_call();
1705                     log_info("AG terminate call");
1706                     break;
1707                 default:
1708                     break;
1709             }
1710             break;
1711         case HFP_AG_CALL_DROPPED:
1712             switch (hfp_gsm_call_status()){
1713                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1714                     switch (hfp_gsm_callsetup_status()){
1715                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1716                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1717                             hfp_ag_stop_ringing();
1718                             break;
1719                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1720                             log_info("Outgoing call interrupted\n");
1721                             break;
1722                         default:
1723                             break;
1724                     }
1725                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1726                     hfp_ag_set_callsetup_indicator();
1727                     hfp_ag_transfer_callsetup_state();
1728                     hfp_ag_trigger_terminate_call();
1729                     break;
1730                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1731                     if (hfp_ag_response_and_hold_active) {
1732                         hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1733                         hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1734                         hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1735                     }
1736                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1737                     hfp_ag_set_callsetup_indicator();
1738                     hfp_ag_set_call_indicator();
1739                     hfp_ag_trigger_terminate_call();
1740                     log_info("AG notify call dropped");
1741                     break;
1742                 default:
1743                     break;
1744             }
1745             break;
1746 
1747         case HFP_AG_OUTGOING_CALL_INITIATED_BY_HF:
1748             // directly reject call if number of free slots is exceeded
1749             if (!hfp_gsm_call_possible()){
1750                 hfp_connection->send_error = 1;
1751                 hfp_ag_run_for_context(hfp_connection);
1752                 break;
1753             }
1754 
1755             // note: number not used currently
1756             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, 0, 0, (const char *) &hfp_connection->line_buffer[3]);
1757 
1758             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1759 
1760             hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, (const char *) &hfp_connection->line_buffer[3]);
1761             break;
1762 
1763         case HFP_AG_OUTGOING_CALL_INITIATED_BY_AG:
1764             // directly reject call if number of free slots is exceeded
1765             if (!hfp_gsm_call_possible()) {
1766                 // TODO: no error for user
1767                 break;
1768             }
1769             switch (hfp_gsm_call_status()) {
1770                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1771                     switch (hfp_gsm_callsetup_status()) {
1772                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1773                             // note: number not used currently
1774                             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, 0, 0, "1234567");
1775                             // init call state for all connections
1776                             hfp_ag_trigger_outgoing_call();
1777                             // get first one and accept call
1778                             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1779                             if (hfp_connection) {
1780                                 hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1781                             }
1782                             break;
1783                         default:
1784                             // TODO: no error for user
1785                             break;
1786                     }
1787                     break;
1788                 default:
1789                     // TODO: no error for user
1790                     break;
1791             }
1792             break;
1793         case HFP_AG_OUTGOING_REDIAL_INITIATED:{
1794             // directly reject call if number of free slots is exceeded
1795             if (!hfp_gsm_call_possible()){
1796                 hfp_connection->send_error = 1;
1797                 hfp_ag_run_for_context(hfp_connection);
1798                 break;
1799             }
1800 
1801             hfp_gsm_handler(HFP_AG_OUTGOING_REDIAL_INITIATED, 0, 0, NULL);
1802             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1803 
1804             log_info("Redial last number");
1805             char * last_dialed_number = hfp_gsm_last_dialed_number();
1806 
1807             if (strlen(last_dialed_number) > 0){
1808                 log_info("Last number exists: accept call");
1809                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, last_dialed_number);
1810             } else {
1811                 log_info("log_infoLast number missing: reject call");
1812                 hfp_ag_handle_reject_outgoing_call();
1813             }
1814             break;
1815         }
1816         case HFP_AG_OUTGOING_CALL_REJECTED:
1817             hfp_ag_handle_reject_outgoing_call();
1818             break;
1819 
1820         case HFP_AG_OUTGOING_CALL_ACCEPTED:{
1821             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1822             if (!hfp_connection){
1823                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1824                 break;
1825             }
1826 
1827             hfp_connection->ok_pending = 1;
1828             hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1829             break;
1830         }
1831         case HFP_AG_OUTGOING_CALL_RINGING:
1832             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1833             if (!hfp_connection){
1834                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in dialing state");
1835                 break;
1836             }
1837 
1838             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_RINGING, 0, 0, NULL);
1839             hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1840             hfp_ag_set_callsetup_indicator();
1841             hfp_ag_transfer_callsetup_state();
1842             hfp_ag_hf_start_ringing_outgoing(hfp_connection);
1843             break;
1844 
1845         case HFP_AG_OUTGOING_CALL_ESTABLISHED:{
1846             // get outgoing call
1847             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_RINGING);
1848             if (!hfp_connection){
1849                 hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1850             }
1851             if (!hfp_connection){
1852                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection");
1853                 break;
1854             }
1855 
1856             bool callheld_status_call_on_hold_and_no_active_calls = hfp_gsm_callheld_status() == HFP_CALLHELD_STATUS_CALL_ON_HOLD_AND_NO_ACTIVE_CALLS;
1857             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ESTABLISHED, 0, 0, NULL);
1858             hfp_connection->call_state = HFP_CALL_ACTIVE;
1859             hfp_ag_set_callsetup_indicator();
1860             hfp_ag_set_call_indicator();
1861             hfp_ag_transfer_call_state();
1862             hfp_ag_transfer_callsetup_state();
1863             if (callheld_status_call_on_hold_and_no_active_calls){
1864                 hfp_ag_set_callheld_indicator();
1865                 hfp_ag_transfer_callheld_state();
1866             }
1867             hfp_ag_hf_stop_ringing(hfp_connection);
1868             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1869             break;
1870         }
1871 
1872         case HFP_AG_CALL_HOLD_USER_BUSY:
1873             hfp_gsm_handler(HFP_AG_CALL_HOLD_USER_BUSY, 0, 0, NULL);
1874             hfp_ag_set_callsetup_indicator();
1875             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1876             hfp_connection->call_state = HFP_CALL_ACTIVE;
1877             log_info("AG: Call Waiting, User Busy");
1878             break;
1879 
1880         case HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1881             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1882             int call_held = hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD;
1883 
1884             // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
1885             if (call_held || call_setup_in_progress){
1886                 hfp_gsm_handler(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index,
1887                                 0, NULL);
1888 
1889             }
1890 
1891             if (call_setup_in_progress){
1892                 log_info("AG: Call Dropped, Accept new call");
1893                 hfp_ag_set_callsetup_indicator();
1894                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1895             } else {
1896                 log_info("AG: Call Dropped, Resume held call");
1897             }
1898             if (call_held){
1899                 hfp_ag_set_callheld_indicator();
1900                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1901             }
1902 
1903             hfp_connection->call_state = HFP_CALL_ACTIVE;
1904             break;
1905         }
1906 
1907         case HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1908             // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
1909             // only update if callsetup changed
1910             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1911             hfp_gsm_handler(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index, 0,
1912                             NULL);
1913 
1914             if (call_setup_in_progress){
1915                 log_info("AG: Call on Hold, Accept new call");
1916                 hfp_ag_set_callsetup_indicator();
1917                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1918             } else {
1919                 log_info("AG: Swap calls");
1920             }
1921 
1922             hfp_ag_set_callheld_indicator();
1923             // hfp_ag_set_callheld_state(HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED);
1924             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1925             hfp_connection->call_state = HFP_CALL_ACTIVE;
1926             break;
1927         }
1928 
1929         case HFP_AG_CALL_HOLD_ADD_HELD_CALL:
1930             // Adds a held call to the conversation.
1931             if (hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD){
1932                 log_info("AG: Join 3-way-call");
1933                 hfp_gsm_handler(HFP_AG_CALL_HOLD_ADD_HELD_CALL, 0, 0, NULL);
1934                 hfp_ag_set_callheld_indicator();
1935                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1936                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1937             }
1938             hfp_connection->call_state = HFP_CALL_ACTIVE;
1939             break;
1940         case HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS:
1941             // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer)
1942             hfp_gsm_handler(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, 0, 0, NULL);
1943             log_info("AG: Transfer call -> Connect two calls and disconnect");
1944             hfp_ag_set_call_indicator();
1945             hfp_ag_set_callheld_indicator();
1946             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1947             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1948             hfp_connection->call_state = HFP_CALL_IDLE;
1949             break;
1950 
1951         default:
1952             break;
1953     }
1954 
1955 
1956 }
1957 
1958 
1959 static void hfp_ag_send_call_status(hfp_connection_t * hfp_connection, int call_index){
1960     hfp_gsm_call_t * active_call = hfp_gsm_call(call_index);
1961     if (!active_call) return;
1962 
1963     int idx = active_call->index;
1964     hfp_enhanced_call_dir_t dir = active_call->direction;
1965     hfp_enhanced_call_status_t status = active_call->enhanced_status;
1966     hfp_enhanced_call_mode_t mode = active_call->mode;
1967     hfp_enhanced_call_mpty_t mpty = active_call->mpty;
1968     uint8_t type = active_call->clip_type;
1969     char * number = active_call->clip_number;
1970 
1971     char buffer[100];
1972     // TODO: check length of a buffer, to fit the MTU
1973     int offset = snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d,%d,%d,%d", HFP_LIST_CURRENT_CALLS, idx, dir, status, mode, mpty);
1974     if (number){
1975         offset += snprintf(buffer+offset, sizeof(buffer)-offset-3, ", \"%s\",%u", number, type);
1976     }
1977     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n");
1978     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,
1979        mode, mpty, type, number);
1980     send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
1981 }
1982 
1983 // sends pending command, returns if command was sent
1984 static int hfp_ag_send_commands(hfp_connection_t *hfp_connection){
1985     if (hfp_connection->send_status_of_current_calls){
1986         hfp_connection->ok_pending = 0;
1987         if (hfp_connection->next_call_index < hfp_gsm_get_number_of_calls()){
1988             hfp_connection->next_call_index++;
1989             hfp_ag_send_call_status(hfp_connection, hfp_connection->next_call_index);
1990             return 1;
1991         } else {
1992             // 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
1993             hfp_connection->next_call_index = 0;
1994             hfp_connection->ok_pending = 1;
1995             hfp_connection->send_status_of_current_calls = 0;
1996         }
1997     }
1998 
1999     if (hfp_connection->ag_notify_incoming_call_waiting){
2000         hfp_connection->ag_notify_incoming_call_waiting = 0;
2001         hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
2002         return 1;
2003     }
2004 
2005     if (hfp_connection->command == HFP_CMD_UNKNOWN){
2006         hfp_connection->ok_pending = 0;
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     if (hfp_connection->send_error){
2014         hfp_connection->send_error = 0;
2015         hfp_connection->command = HFP_CMD_NONE;
2016         hfp_ag_send_error(hfp_connection->rfcomm_cid);
2017         return 1;
2018     }
2019 
2020     // note: before update AG indicators and ok_pending
2021     if (hfp_connection->send_response_and_hold_status){
2022         int status = hfp_connection->send_response_and_hold_status - 1;
2023         hfp_connection->send_response_and_hold_status = 0;
2024         hfp_ag_send_set_response_and_hold(hfp_connection->rfcomm_cid, status);
2025         return 1;
2026     }
2027 
2028     if (hfp_connection->ok_pending){
2029         hfp_connection->ok_pending = 0;
2030         hfp_connection->command = HFP_CMD_NONE;
2031         hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2032         return 1;
2033     }
2034 
2035     // update AG indicators
2036     if (hfp_connection->ag_indicators_status_update_bitmap){
2037         int i;
2038         for (i=0;i<hfp_connection->ag_indicators_nr;i++){
2039             if (get_bit(hfp_connection->ag_indicators_status_update_bitmap, i)){
2040                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, i, 0);
2041                 if (!hfp_connection->enable_status_update_for_ag_indicators) {
2042                     log_info("+CMER:3,0,0,0 - not sending update for '%s'", hfp_ag_indicators[i].name);
2043                     break;
2044                 }
2045                 hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[i]);
2046                 return 1;
2047             }
2048         }
2049     }
2050 
2051     if (hfp_connection->ag_send_no_carrier){
2052         hfp_connection->ag_send_no_carrier = false;
2053         hfp_ag_send_no_carrier(hfp_connection->rfcomm_cid);
2054         return 1;
2055     }
2056 
2057     if (hfp_connection->ag_ring){
2058         hfp_connection->ag_ring = 0;
2059         hfp_connection->command = HFP_CMD_NONE;
2060         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_RING);
2061         hfp_ag_send_ring(hfp_connection->rfcomm_cid);
2062         return 1;
2063     }
2064 
2065     if (hfp_connection->ag_send_clip){
2066         hfp_connection->ag_send_clip = 0;
2067         hfp_connection->command = HFP_CMD_NONE;
2068         hfp_ag_send_clip(hfp_connection->rfcomm_cid);
2069         return 1;
2070     }
2071 
2072     if (hfp_connection->send_phone_number_for_voice_tag){
2073         hfp_connection->send_phone_number_for_voice_tag = 0;
2074         hfp_connection->command = HFP_CMD_NONE;
2075         hfp_connection->ok_pending = 1;
2076         hfp_ag_send_phone_number_for_voice_tag_cmd(hfp_connection->rfcomm_cid);
2077         return 1;
2078     }
2079 
2080     if (hfp_connection->send_subscriber_number){
2081         if (hfp_connection->next_subscriber_number_to_send < hfp_ag_subscriber_numbers_count){
2082             hfp_phone_number_t phone = hfp_ag_subscriber_numbers[hfp_connection->next_subscriber_number_to_send++];
2083             hfp_send_subscriber_number_cmd(hfp_connection->rfcomm_cid, phone.type, phone.number);
2084         } else {
2085             hfp_connection->send_subscriber_number = 0;
2086             hfp_connection->next_subscriber_number_to_send = 0;
2087             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2088         }
2089         hfp_connection->command = HFP_CMD_NONE;
2090         return 1;
2091     }
2092 
2093     if (hfp_connection->send_microphone_gain){
2094         hfp_connection->send_microphone_gain = 0;
2095         hfp_connection->command = HFP_CMD_NONE;
2096         hfp_ag_send_set_microphone_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->microphone_gain);
2097         return 1;
2098     }
2099 
2100     if (hfp_connection->send_speaker_gain){
2101         hfp_connection->send_speaker_gain = 0;
2102         hfp_connection->command = HFP_CMD_NONE;
2103         hfp_ag_send_set_speaker_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->speaker_gain);
2104         return 1;
2105     }
2106 
2107     if (hfp_connection->send_ag_status_indicators){
2108         hfp_connection->send_ag_status_indicators = 0;
2109         hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
2110         return 1;
2111     }
2112 
2113     return 0;
2114 }
2115 
2116 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection){
2117 
2118 	btstack_assert(hfp_connection != NULL);
2119 	btstack_assert(hfp_connection->local_role == HFP_ROLE_AG);
2120 
2121 	// during SDP query, RFCOMM CID is not set
2122 	if (hfp_connection->rfcomm_cid == 0) return;
2123 
2124     // assert command could be sent
2125     if (hci_can_send_command_packet_now() == 0) return;
2126 
2127     if ((hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) && hfp_connection->release_audio_connection){
2128         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
2129         hfp_connection->release_audio_connection = 0;
2130         gap_disconnect(hfp_connection->sco_handle);
2131         return;
2132     }
2133 
2134 #ifdef ENABLE_CC256X_ASSISTED_HFP
2135     // WBS Disassociate
2136     if (hfp_connection->cc256x_send_wbs_disassociate){
2137         hfp_connection->cc256x_send_wbs_disassociate = false;
2138         hci_send_cmd(&hci_ti_wbs_disassociate);
2139         return;
2140     }
2141     // Write Codec Config
2142     if (hfp_connection->cc256x_send_write_codec_config){
2143         hfp_connection->cc256x_send_write_codec_config = false;
2144         hfp_cc256x_write_codec_config(hfp_connection);
2145         return;
2146     }
2147     // WBS Associate
2148     if (hfp_connection->cc256x_send_wbs_associate){
2149         hfp_connection->cc256x_send_wbs_associate = false;
2150         hci_send_cmd(&hci_ti_wbs_associate, hfp_connection->acl_handle);
2151         return;
2152     }
2153 #endif
2154 #ifdef ENABLE_BCM_PCM_WBS
2155     // Enable WBS
2156     if (hfp_connection->bcm_send_enable_wbs){
2157         hfp_connection->bcm_send_enable_wbs = false;
2158         hci_send_cmd(&hci_bcm_enable_wbs, 1, 2);
2159         return;
2160     }
2161     // Write I2S/PCM params
2162     if (hfp_connection->bcm_send_write_i2spcm_interface_param){
2163         hfp_connection->bcm_send_write_i2spcm_interface_param = false;
2164         hfp_bcm_write_i2spcm_interface_param(hfp_connection);
2165         return;
2166     }
2167     // Disable WBS
2168     if (hfp_connection->bcm_send_disable_wbs){
2169         hfp_connection->bcm_send_disable_wbs = false;
2170         hci_send_cmd(&hci_bcm_enable_wbs, 0, 2);
2171         return;
2172     }
2173 #endif
2174 #if defined (ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
2175     if (hfp_connection->state == HFP_W4_WBS_SHUTDOWN){
2176         hfp_finalize_connection_context(hfp_connection);
2177         return;
2178     }
2179 #endif
2180 
2181     if (!rfcomm_can_send_packet_now(hfp_connection->rfcomm_cid)) {
2182         log_info("hfp_ag_run_for_context: request can send for 0x%02x", hfp_connection->rfcomm_cid);
2183         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2184         return;
2185     }
2186 
2187     int cmd_sent = hfp_ag_send_commands(hfp_connection);
2188 
2189     if (!cmd_sent){
2190         cmd_sent = hfp_ag_run_for_context_service_level_connection(hfp_connection);
2191     }
2192 
2193     if (!cmd_sent){
2194         cmd_sent = hfp_ag_run_for_context_service_level_connection_queries(hfp_connection);
2195     }
2196 
2197     if (!cmd_sent){
2198         cmd_sent = call_setup_state_machine(hfp_connection);
2199     }
2200 
2201     // trigger codec exchange (must be before hfp_ag_run_for_audio_connection)
2202     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && hfp_connection->trigger_codec_exchange){
2203         switch (hfp_connection->codecs_state){
2204             case HFP_CODECS_IDLE:
2205             case HFP_CODECS_RECEIVED_LIST:
2206             case HFP_CODECS_AG_RESEND_COMMON_CODEC:
2207             case HFP_CODECS_ERROR:
2208                 hfp_connection->trigger_codec_exchange = 0;
2209                 hfp_connection->command = HFP_CMD_AG_SEND_COMMON_CODEC;
2210                 break;
2211             default:
2212                 break;
2213         }
2214     }
2215 
2216     if (!cmd_sent){
2217         cmd_sent = hfp_ag_run_for_audio_connection(hfp_connection);
2218     }
2219 
2220     if (!cmd_sent){
2221         cmd_sent = hfp_ag_voice_recognition_state_machine(hfp_connection);
2222     }
2223 
2224     // disconnect
2225     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && (hfp_connection->state == HFP_W2_DISCONNECT_RFCOMM)){
2226         hfp_connection->state = HFP_W4_RFCOMM_DISCONNECTED;
2227         rfcomm_disconnect(hfp_connection->rfcomm_cid);
2228     }
2229 
2230     if (cmd_sent){
2231         hfp_connection->command = HFP_CMD_NONE;
2232         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2233     }
2234 }
2235 
2236 static int hfp_parser_is_end_of_line(uint8_t byte){
2237     return (byte == '\n') || (byte == '\r');
2238 }
2239 
2240 static void hfp_ag_handle_rfcomm_data(hfp_connection_t * hfp_connection, uint8_t *packet, uint16_t size){
2241     // assertion: size >= 1 as rfcomm.c does not deliver empty packets
2242     if (size < 1) return;
2243     uint8_t status = ERROR_CODE_SUCCESS;
2244 
2245     hfp_log_rfcomm_message("HFP_AG_RX", packet, size);
2246 #ifdef ENABLE_HFP_AT_MESSAGES
2247     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_RECEIVED, (char *) packet);
2248 #endif
2249 
2250     // process messages byte-wise
2251     int pos;
2252     for (pos = 0; pos < size ; pos++){
2253         hfp_parse(hfp_connection, packet[pos], 0);
2254 
2255         // parse until end of line
2256         if (!hfp_parser_is_end_of_line(packet[pos])) continue;
2257 
2258         hfp_generic_status_indicator_t * indicator;
2259         switch(hfp_connection->command){
2260             case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
2261                 // dealt with in hfp_ag_voice_recognition_state_machine
2262                 break;
2263             case HFP_CMD_RESPONSE_AND_HOLD_QUERY:
2264                 if (hfp_ag_response_and_hold_active){
2265                     hfp_connection->send_response_and_hold_status = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD + 1;
2266                 }
2267                 hfp_connection->ok_pending = 1;
2268                 break;
2269             case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
2270                 switch(hfp_connection->ag_response_and_hold_action){
2271                     case HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD:
2272                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, hfp_connection);
2273                         break;
2274                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED:
2275                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF, hfp_connection);
2276                         break;
2277                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED:
2278                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF, hfp_connection);
2279                         break;
2280                     default:
2281                         break;
2282                 }
2283                 hfp_connection->ok_pending = 1;
2284                 break;
2285             case HFP_CMD_HF_INDICATOR_STATUS:
2286                 hfp_connection->command = HFP_CMD_NONE;
2287 
2288                 if (hfp_connection->parser_indicator_index < hfp_ag_generic_status_indicators_nr){
2289                     indicator = &hfp_ag_generic_status_indicators[hfp_connection->parser_indicator_index];
2290                     switch (indicator->uuid){
2291                         case HFP_HF_INDICATOR_UUID_ENHANCED_SAFETY:
2292                             if (hfp_connection->parser_indicator_value > 1) {
2293                                 hfp_connection->send_error = 1;
2294                                 break;
2295                             }
2296                             hfp_connection->ok_pending = 1;
2297                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2298                             break;
2299                         case HFP_HF_INDICATOR_UUID_BATTERY_LEVEL:
2300                             if (hfp_connection->parser_indicator_value > 100){
2301                                 hfp_connection->send_error = 1;
2302                                 break;
2303                             }
2304                             hfp_connection->ok_pending = 1;
2305                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2306                             break;
2307                         default:
2308                             hfp_connection->send_error = 1;
2309                             break;
2310                     }
2311                 } else {
2312                     hfp_connection->send_error = 1;
2313                 }
2314                 break;
2315             case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
2316                 // expected by SLC state machine
2317                 if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) break;
2318                 hfp_connection->send_ag_indicators_segment = 0;
2319                 hfp_connection->send_ag_status_indicators = 1;
2320                 break;
2321             case HFP_CMD_LIST_CURRENT_CALLS:
2322                 hfp_connection->command = HFP_CMD_NONE;
2323                 hfp_connection->next_call_index = 0;
2324                 hfp_connection->send_status_of_current_calls = 1;
2325                 break;
2326             case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
2327                 if (hfp_ag_subscriber_numbers_count == 0){
2328                     hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2329                     break;
2330                 }
2331                 hfp_connection->next_subscriber_number_to_send = 0;
2332                 hfp_connection->send_subscriber_number = 1;
2333                 break;
2334             case HFP_CMD_TRANSMIT_DTMF_CODES:
2335             {
2336                 hfp_connection->command = HFP_CMD_NONE;
2337                 char buffer[2];
2338                 buffer[0] = (char) hfp_connection->ag_dtmf_code;
2339                 buffer[1] = 0;
2340                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_TRANSMIT_DTMF_CODES, buffer);
2341                 break;
2342             }
2343             case HFP_CMD_HF_REQUEST_PHONE_NUMBER:
2344                 hfp_connection->command = HFP_CMD_NONE;
2345                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_ATTACH_NUMBER_TO_VOICE_TAG);
2346                 break;
2347             case HFP_CMD_TURN_OFF_EC_AND_NR:
2348                 hfp_connection->command = HFP_CMD_NONE;
2349 
2350                 if (get_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION)){
2351                     hfp_connection->ok_pending = 1;
2352                     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION, hfp_connection->ag_echo_and_noise_reduction);
2353                     status = ERROR_CODE_SUCCESS;
2354                 } else {
2355                     hfp_connection->send_error = 1;
2356                     status = ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2357                 }
2358                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_ECHO_CANCELING_AND_NOISE_REDUCTION_DEACTIVATE, status);
2359                 break;
2360             case HFP_CMD_CALL_ANSWERED:
2361                 hfp_connection->command = HFP_CMD_NONE;
2362                 log_info("HFP: ATA");
2363                 hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, hfp_connection);
2364                 break;
2365             case HFP_CMD_HANG_UP_CALL:
2366                 hfp_connection->command = HFP_CMD_NONE;
2367                 hfp_connection->ok_pending = 1;
2368                 hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_HF, hfp_connection);
2369                 break;
2370             case HFP_CMD_CALL_HOLD: {
2371                 hfp_connection->command = HFP_CMD_NONE;
2372                 hfp_connection->ok_pending = 1;
2373 
2374                 switch (hfp_connection->ag_call_hold_action){
2375                     case 0:
2376                         // Releases all held calls or sets User Determined User Busy (UDUB) for a waiting call.
2377                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_USER_BUSY, hfp_connection);
2378                         break;
2379                     case 1:
2380                         // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
2381                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2382                         // waiting call (i.e., not to the held call) in conflicting situation.
2383                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2384                         break;
2385                     case 2:
2386                         // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
2387                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2388                         // waiting call (i.e., not to the held call) in conflicting situation.
2389                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2390                         break;
2391                     case 3:
2392                         // Adds a held call to the conversation.
2393                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_ADD_HELD_CALL, hfp_connection);
2394                         break;
2395                     case 4:
2396                         // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer).
2397                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, hfp_connection);
2398                         break;
2399                     default:
2400                         break;
2401                 }
2402 				hfp_connection->call_index = 0;
2403                 break;
2404             }
2405             case HFP_CMD_CALL_PHONE_NUMBER:
2406                 hfp_connection->command = HFP_CMD_NONE;
2407                 hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, hfp_connection);
2408                 break;
2409             case HFP_CMD_REDIAL_LAST_NUMBER:
2410                 hfp_connection->command = HFP_CMD_NONE;
2411                 hfp_ag_call_sm(HFP_AG_OUTGOING_REDIAL_INITIATED, hfp_connection);
2412                 break;
2413             case HFP_CMD_ENABLE_CLIP:
2414                 hfp_connection->command = HFP_CMD_NONE;
2415                 log_info("hfp: clip set, now: %u", hfp_connection->clip_enabled);
2416                 hfp_connection->ok_pending = 1;
2417                 break;
2418             case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
2419                 hfp_connection->command = HFP_CMD_NONE;
2420                 log_info("hfp: call waiting notification set, now: %u", hfp_connection->call_waiting_notification_enabled);
2421                 hfp_connection->ok_pending = 1;
2422                 break;
2423             case HFP_CMD_SET_SPEAKER_GAIN:
2424                 hfp_connection->command = HFP_CMD_NONE;
2425                 hfp_connection->ok_pending = 1;
2426                 log_info("HF speaker gain = %u", hfp_connection->speaker_gain);
2427                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_SPEAKER_VOLUME, hfp_connection->speaker_gain);
2428                 break;
2429             case HFP_CMD_SET_MICROPHONE_GAIN:
2430                 hfp_connection->command = HFP_CMD_NONE;
2431                 hfp_connection->ok_pending = 1;
2432                 log_info("HF microphone gain = %u", hfp_connection->microphone_gain);
2433                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_MICROPHONE_VOLUME, hfp_connection->microphone_gain);
2434                 break;
2435             default:
2436                 break;
2437         }
2438     }
2439 }
2440 
2441 static void hfp_ag_run(void){
2442     btstack_linked_list_iterator_t it;
2443     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2444     while (btstack_linked_list_iterator_has_next(&it)){
2445         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2446         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2447         hfp_ag_run_for_context(hfp_connection);
2448     }
2449 }
2450 
2451 static void hfp_ag_rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2452     hfp_connection_t * hfp_connection = NULL;
2453     switch (packet_type){
2454         case RFCOMM_DATA_PACKET:
2455             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(channel);
2456             btstack_assert(hfp_connection != NULL);
2457 
2458             hfp_ag_handle_rfcomm_data(hfp_connection, packet, size);
2459             hfp_ag_run_for_context(hfp_connection);
2460             return;
2461         case HCI_EVENT_PACKET:
2462             if (packet[0] == RFCOMM_EVENT_CAN_SEND_NOW){
2463                 uint16_t rfcomm_cid = rfcomm_event_can_send_now_get_rfcomm_cid(packet);
2464                 hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
2465                 btstack_assert(hfp_connection != NULL);
2466 
2467                 hfp_ag_run_for_context(hfp_connection);
2468                 return;
2469             }
2470             hfp_handle_rfcomm_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2471             break;
2472         default:
2473             break;
2474     }
2475 
2476     hfp_ag_run();
2477 }
2478 
2479 static void hfp_ag_hci_event_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2480     hfp_handle_hci_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2481     hfp_ag_run();
2482 }
2483 
2484 void hfp_ag_init_codecs(int codecs_nr, const uint8_t * codecs){
2485     if (codecs_nr > HFP_MAX_NUM_CODECS){
2486         log_error("hfp_init: codecs_nr (%d) > HFP_MAX_NUM_CODECS (%d)", codecs_nr, HFP_MAX_NUM_CODECS);
2487         return;
2488     }
2489     int i;
2490     hfp_ag_codecs_nr = codecs_nr;
2491     for (i=0; i < codecs_nr; i++){
2492         hfp_ag_codecs[i] = codecs[i];
2493     }
2494 }
2495 
2496 void hfp_ag_init_supported_features(uint32_t supported_features){
2497     hfp_ag_supported_features = supported_features;
2498 }
2499 
2500 void hfp_ag_init_ag_indicators(int ag_indicators_nr, const hfp_ag_indicator_t * ag_indicators){
2501     hfp_ag_indicators_nr = ag_indicators_nr;
2502     (void)memcpy(hfp_ag_indicators, ag_indicators,
2503                  ag_indicators_nr * sizeof(hfp_ag_indicator_t));
2504 }
2505 
2506 void hfp_ag_init_hf_indicators(int hf_indicators_nr, const hfp_generic_status_indicator_t * hf_indicators){
2507     if (hf_indicators_nr > HFP_MAX_NUM_INDICATORS) return;
2508     hfp_ag_generic_status_indicators_nr = hf_indicators_nr;
2509     (void)memcpy(hfp_ag_generic_status_indicators, hf_indicators,
2510                  hf_indicators_nr * sizeof(hfp_generic_status_indicator_t));
2511 }
2512 
2513 void hfp_ag_init_call_hold_services(int call_hold_services_nr, const char * call_hold_services[]){
2514     hfp_ag_call_hold_services_nr = call_hold_services_nr;
2515     (void)memcpy(hfp_ag_call_hold_services, call_hold_services,
2516                  call_hold_services_nr * sizeof(char *));
2517 }
2518 
2519 
2520 void hfp_ag_init(uint16_t rfcomm_channel_nr){
2521 
2522     hfp_init();
2523     hfp_ag_call_hold_services_nr = 0;
2524     hfp_ag_response_and_hold_active = 0;
2525     hfp_ag_indicators_nr = 0;
2526     hfp_ag_codecs_nr = 0;
2527     hfp_ag_supported_features = HFP_DEFAULT_AG_SUPPORTED_FEATURES;
2528     hfp_ag_subscriber_numbers = NULL;
2529     hfp_ag_subscriber_numbers_count = 0;
2530 
2531     hfp_ag_hci_event_callback_registration.callback = &hfp_ag_hci_event_packet_handler;
2532     hci_add_event_handler(&hfp_ag_hci_event_callback_registration);
2533 
2534     rfcomm_register_service(&hfp_ag_rfcomm_packet_handler, rfcomm_channel_nr, 0xffff);
2535 
2536     // used to set packet handler for outgoing rfcomm connections - could be handled by emitting an event to us
2537     hfp_set_ag_rfcomm_packet_handler(&hfp_ag_rfcomm_packet_handler);
2538 
2539     hfp_gsm_init();
2540 }
2541 
2542 void hfp_ag_deinit(void){
2543     hfp_deinit();
2544     hfp_gsm_deinit();
2545 
2546     hfp_ag_callback = NULL;
2547     hfp_ag_supported_features = 0;
2548     hfp_ag_codecs_nr = 0;
2549     hfp_ag_indicators_nr = 0;
2550     hfp_ag_call_hold_services_nr = 0;
2551     (void) memset(&hfp_ag_call_hold_services, 0, sizeof(hfp_ag_call_hold_services));
2552     hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
2553     (void) memset(&hfp_ag_response_and_hold_state, 0, sizeof(hfp_response_and_hold_state_t));
2554     hfp_ag_subscriber_numbers = NULL;
2555     (void) memset(&hfp_ag_hci_event_callback_registration, 0, sizeof(btstack_packet_callback_registration_t));
2556 }
2557 
2558 uint8_t hfp_ag_establish_service_level_connection(bd_addr_t bd_addr){
2559     return hfp_establish_service_level_connection(bd_addr, BLUETOOTH_SERVICE_CLASS_HANDSFREE, HFP_ROLE_AG);
2560 }
2561 
2562 uint8_t hfp_ag_release_service_level_connection(hci_con_handle_t acl_handle){
2563     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2564     if (!hfp_connection){
2565         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2566     }
2567 
2568     hfp_trigger_release_service_level_connection(hfp_connection);
2569     hfp_ag_run_for_context(hfp_connection);
2570     return ERROR_CODE_SUCCESS;
2571 }
2572 
2573 uint8_t hfp_ag_report_extended_audio_gateway_error_result_code(hci_con_handle_t acl_handle, hfp_cme_error_t error){
2574     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2575     if (!hfp_connection){
2576         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2577     }
2578 
2579     hfp_connection->extended_audio_gateway_error = 0;
2580     if (!hfp_connection->enable_extended_audio_gateway_error_report){
2581         return ERROR_CODE_COMMAND_DISALLOWED;
2582     }
2583 
2584     hfp_connection->extended_audio_gateway_error = error;
2585     hfp_ag_run_for_context(hfp_connection);
2586     return ERROR_CODE_SUCCESS;
2587 }
2588 
2589 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection){
2590     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
2591         return ERROR_CODE_COMMAND_DISALLOWED;
2592     }
2593     if (hfp_connection->state >= HFP_W2_DISCONNECT_SCO){
2594         return ERROR_CODE_COMMAND_DISALLOWED;
2595     }
2596 
2597     hfp_connection->establish_audio_connection = 1;
2598     if (!has_codec_negotiation_feature(hfp_connection)){
2599         log_info("hfp_ag_establish_audio_connection - no codec negotiation feature, using CVSD");
2600         hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
2601         hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
2602         // now, pick link settings
2603         hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
2604 #ifdef ENABLE_CC256X_ASSISTED_HFP
2605         hfp_cc256x_prepare_for_sco(hfp_connection);
2606 #endif
2607         return ERROR_CODE_SUCCESS;
2608     }
2609 
2610     uint8_t i;
2611     bool codec_was_in_use = false;
2612     bool better_codec_can_be_used = false;
2613 
2614     for (i = 0; i<hfp_connection->remote_codecs_nr; i++){
2615         if (hfp_connection->negotiated_codec == hfp_connection->remote_codecs[i]){
2616             codec_was_in_use = true;
2617         } else if (hfp_connection->negotiated_codec < hfp_connection->remote_codecs[i]){
2618             better_codec_can_be_used = true;
2619         }
2620     }
2621 
2622     if (!codec_was_in_use || better_codec_can_be_used){
2623         hfp_connection->trigger_codec_exchange = 1;
2624         hfp_connection->codecs_state = HFP_CODECS_IDLE;
2625     }
2626     return ERROR_CODE_SUCCESS;
2627 }
2628 
2629 uint8_t hfp_ag_establish_audio_connection(hci_con_handle_t acl_handle){
2630     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2631     if (!hfp_connection){
2632         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2633     }
2634     uint8_t status = hfp_ag_setup_audio_connection(hfp_connection);
2635     if (status != ERROR_CODE_SUCCESS){
2636         return status;
2637     }
2638     hfp_ag_run_for_context(hfp_connection);
2639     return ERROR_CODE_SUCCESS;
2640 }
2641 
2642 uint8_t hfp_ag_release_audio_connection(hci_con_handle_t acl_handle){
2643     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2644     if (!hfp_connection){
2645         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2646     }
2647 
2648     if (hfp_connection->vra_state == HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
2649         return ERROR_CODE_COMMAND_DISALLOWED;
2650     }
2651 
2652     uint8_t status = hfp_trigger_release_audio_connection(hfp_connection);
2653     if (status == ERROR_CODE_SUCCESS){
2654         hfp_ag_run_for_context(hfp_connection);
2655     }
2656     return status;
2657 }
2658 
2659 /**
2660  * @brief Enable in-band ring tone
2661  */
2662 void hfp_ag_set_use_in_band_ring_tone(int use_in_band_ring_tone){
2663     if (get_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE) == use_in_band_ring_tone){
2664         return;
2665     }
2666 
2667     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE, use_in_band_ring_tone);
2668 
2669     btstack_linked_list_iterator_t it;
2670     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2671     while (btstack_linked_list_iterator_has_next(&it)){
2672         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2673         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2674         hfp_connection->command = HFP_CMD_CHANGE_IN_BAND_RING_TONE_SETTING;
2675         hfp_ag_run_for_context(hfp_connection);
2676     }
2677 }
2678 
2679 /**
2680  * @brief Called from GSM
2681  */
2682 void hfp_ag_incoming_call(void){
2683     hfp_ag_call_sm(HFP_AG_INCOMING_CALL, NULL);
2684 }
2685 
2686 void hfp_ag_outgoing_call_initiated(const char * number) {
2687     UNUSED(number);
2688     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, NULL);
2689 }
2690 
2691 /**
2692  * @brief number is stored.
2693  */
2694 void hfp_ag_set_clip(uint8_t type, const char * number){
2695     hfp_gsm_handler(HFP_AG_SET_CLIP, 0, type, number);
2696 }
2697 
2698 void hfp_ag_call_dropped(void){
2699     hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2700 }
2701 
2702 // call from AG UI
2703 void hfp_ag_answer_incoming_call(void){
2704     hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, NULL);
2705 }
2706 
2707 void hfp_ag_join_held_call(void){
2708     hfp_ag_call_sm(HFP_AG_HELD_CALL_JOINED_BY_AG, NULL);
2709 }
2710 
2711 void hfp_ag_terminate_call(void){
2712     hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_AG, NULL);
2713 }
2714 
2715 void hfp_ag_outgoing_call_ringing(void){
2716     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_RINGING, NULL);
2717 }
2718 
2719 void hfp_ag_outgoing_call_established(void){
2720     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ESTABLISHED, NULL);
2721 }
2722 
2723 void hfp_ag_outgoing_call_rejected(void){
2724     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_REJECTED, NULL);
2725 }
2726 
2727 void hfp_ag_outgoing_call_accepted(void){
2728     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ACCEPTED, NULL);
2729 }
2730 
2731 void hfp_ag_hold_incoming_call(void){
2732     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, NULL);
2733 }
2734 
2735 void hfp_ag_accept_held_incoming_call(void) {
2736     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, NULL);
2737 }
2738 
2739 void hfp_ag_reject_held_incoming_call(void){
2740     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, NULL);
2741 }
2742 
2743 static void hfp_ag_set_ag_indicator(const char * name, int value){
2744     int indicator_index = get_ag_indicator_index_for_name(name);
2745     if (indicator_index < 0) return;
2746     hfp_ag_indicators[indicator_index].status = value;
2747 
2748     btstack_linked_list_iterator_t it;
2749     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2750     while (btstack_linked_list_iterator_has_next(&it)){
2751         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2752         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2753         if (!hfp_connection->ag_indicators[indicator_index].enabled) {
2754             log_info("Requested AG indicator '%s' update to %u, but it is not enabled", hfp_ag_indicators[indicator_index].name, value);
2755             continue;
2756         }
2757         log_info("AG indicator '%s' changed to %u, request transfer status", hfp_ag_indicators[indicator_index].name, value);
2758         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
2759         hfp_ag_run_for_context(hfp_connection);
2760     }
2761 }
2762 
2763 uint8_t hfp_ag_set_registration_status(int registration_status){
2764     if ((registration_status < 0) || (registration_status > 1)){
2765         return ERROR_CODE_COMMAND_DISALLOWED;
2766     }
2767 
2768     if ( (registration_status == 0) && (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT)){
2769 
2770         // if network goes away wihle a call is active:
2771         // - the  call gets dropped
2772         // - we send NO CARRIER
2773         // NOTE: the CALL=0 has to be sent before NO CARRIER
2774 
2775         hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2776 
2777         btstack_linked_list_iterator_t it;
2778         btstack_linked_list_iterator_init(&it, hfp_get_connections());
2779         while (btstack_linked_list_iterator_has_next(&it)){
2780             hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2781             hfp_connection->ag_send_no_carrier = true;
2782         }
2783     }
2784     hfp_ag_set_ag_indicator("service", registration_status);
2785     return ERROR_CODE_SUCCESS;
2786 }
2787 
2788 uint8_t hfp_ag_set_signal_strength(int signal_strength){
2789     if ((signal_strength < 0) || (signal_strength > 5)){
2790         return ERROR_CODE_COMMAND_DISALLOWED;
2791     }
2792 
2793     hfp_ag_set_ag_indicator("signal", signal_strength);
2794     return ERROR_CODE_SUCCESS;
2795 }
2796 
2797 uint8_t hfp_ag_set_roaming_status(int roaming_status){
2798     if ((roaming_status < 0) || (roaming_status > 1)){
2799         return ERROR_CODE_COMMAND_DISALLOWED;
2800     }
2801 
2802     hfp_ag_set_ag_indicator("roam", roaming_status);
2803     return ERROR_CODE_SUCCESS;
2804 }
2805 
2806 uint8_t hfp_ag_set_battery_level(int battery_level){
2807     if ((battery_level < 0) || (battery_level > 5)){
2808         return ERROR_CODE_COMMAND_DISALLOWED;
2809     }
2810     hfp_ag_set_ag_indicator("battchg", battery_level);
2811     return ERROR_CODE_SUCCESS;
2812 }
2813 
2814 static uint8_t activate_voice_recognition(hci_con_handle_t acl_handle, bool enhanced){
2815     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2816     if (!hfp_connection){
2817         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2818     }
2819 
2820     uint8_t status = hfp_ag_can_activate_voice_recognition(hfp_connection, enhanced);
2821     if (status == ERROR_CODE_SUCCESS){
2822         hfp_connection->ag_activate_voice_recognition_value = 1;
2823         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
2824         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2825         hfp_connection->enhanced_voice_recognition_enabled = enhanced;
2826         hfp_connection->ag_audio_connection_opened_before_vra = hfp_ag_is_audio_connection_active(hfp_connection);
2827         hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2828         hfp_ag_run_for_context(hfp_connection);
2829     }
2830     return status;
2831 }
2832 
2833 static uint8_t deactivate_voice_recognition(hci_con_handle_t acl_handle, bool enhanced){
2834     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2835     if (!hfp_connection){
2836         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2837     }
2838     uint8_t status = hfp_ag_voice_recognition_session_active(hfp_connection, enhanced);
2839     if (status == ERROR_CODE_SUCCESS){
2840         hfp_connection->ag_activate_voice_recognition_value = 0;
2841         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
2842         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2843         hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2844         hfp_ag_run_for_context(hfp_connection);
2845     }
2846     return status;
2847 }
2848 
2849 uint8_t hfp_ag_activate_voice_recognition(hci_con_handle_t acl_handle){
2850     return activate_voice_recognition(acl_handle, false);
2851 }
2852 
2853 uint8_t hfp_ag_activate_enhanced_voice_recognition(hci_con_handle_t acl_handle){
2854     return activate_voice_recognition(acl_handle, true);
2855 }
2856 
2857 uint8_t hfp_ag_deactivate_voice_recognition(hci_con_handle_t acl_handle){
2858     return deactivate_voice_recognition(acl_handle, false);
2859 }
2860 
2861 uint8_t hfp_ag_deactivate_enhanced_voice_recognition(hci_con_handle_t acl_handle){
2862     return deactivate_voice_recognition(acl_handle, true);
2863 }
2864 
2865 static uint8_t hfp_ag_enhanced_voice_recognition_send_state(hci_con_handle_t acl_handle, hfp_voice_recognition_state_t state){
2866     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2867     if (!hfp_connection){
2868         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2869     }
2870 
2871     uint8_t status = hfp_ag_voice_recognition_session_active(hfp_connection, true);
2872     if (status == ERROR_CODE_SUCCESS){
2873         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2874         hfp_connection->ag_vra_state = state;
2875         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS;
2876         hfp_ag_run_for_context(hfp_connection);
2877     }
2878     return status;
2879 }
2880 
2881 uint8_t hfp_ag_enhanced_voice_recognition_report_sending_audio(hci_con_handle_t acl_handle){
2882     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_STARTING_SOUND);
2883 }
2884 uint8_t hfp_ag_enhanced_voice_recognition_report_ready_for_audio(hci_con_handle_t acl_handle){
2885     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_READY_TO_ACCEPT_AUDIO_INPUT);
2886 }
2887 uint8_t hfp_ag_enhanced_voice_recognition_report_processing_input(hci_con_handle_t acl_handle){
2888     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_PROCESSING_AUDIO_INPUT);
2889 }
2890 
2891 
2892 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){
2893     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2894     if (!hfp_connection){
2895         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2896     }
2897 
2898     uint8_t status = hfp_ag_can_send_enahnced_voice_recognition_message(hfp_connection, true);
2899     if (status == ERROR_CODE_SUCCESS){
2900         hfp_connection->command = HFP_CMD_AG_ACTIVATE_VOICE_RECOGNITION;
2901         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG;
2902         hfp_connection->ag_msg = msg;
2903         hfp_connection->ag_vra_state = state;
2904         hfp_ag_run_for_context(hfp_connection);
2905     }
2906     return status;
2907 }
2908 
2909 
2910 uint8_t hfp_ag_set_microphone_gain(hci_con_handle_t acl_handle, int gain){
2911     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2912     if (!hfp_connection){
2913         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2914     }
2915 
2916     if ((gain < 0) || (gain > 15)){
2917         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
2918         return ERROR_CODE_COMMAND_DISALLOWED;
2919     }
2920 
2921     if (hfp_connection->microphone_gain != gain){
2922         hfp_connection->command = HFP_CMD_SET_MICROPHONE_GAIN;
2923         hfp_connection->microphone_gain = gain;
2924         hfp_connection->send_microphone_gain = 1;
2925     }
2926     hfp_ag_run_for_context(hfp_connection);
2927     return ERROR_CODE_SUCCESS;
2928 }
2929 
2930 uint8_t hfp_ag_set_speaker_gain(hci_con_handle_t acl_handle, int gain){
2931     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2932     if (!hfp_connection){
2933         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2934     }
2935 
2936     if ((gain < 0) || (gain > 15)){
2937         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
2938         return ERROR_CODE_COMMAND_DISALLOWED;
2939     }
2940 
2941     if (hfp_connection->speaker_gain != gain){
2942         hfp_connection->speaker_gain = gain;
2943         hfp_connection->send_speaker_gain = 1;
2944     }
2945     hfp_ag_run_for_context(hfp_connection);
2946     return ERROR_CODE_SUCCESS;
2947 }
2948 
2949 uint8_t hfp_ag_send_phone_number_for_voice_tag(hci_con_handle_t acl_handle, const char * number){
2950     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2951     if (!hfp_connection){
2952         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2953     }
2954 
2955     hfp_ag_set_clip(0, number);
2956     hfp_connection->send_phone_number_for_voice_tag = 1;
2957     return ERROR_CODE_SUCCESS;
2958 }
2959 
2960 uint8_t hfp_ag_reject_phone_number_for_voice_tag(hci_con_handle_t acl_handle){
2961     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2962     if (!hfp_connection){
2963         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2964     }
2965 
2966     hfp_connection->send_error = 1;
2967     return ERROR_CODE_SUCCESS;
2968 }
2969 
2970 uint8_t hfp_ag_send_dtmf_code_done(hci_con_handle_t acl_handle){
2971     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2972     if (!hfp_connection){
2973         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2974     }
2975 
2976     hfp_connection->ok_pending = 1;
2977     return ERROR_CODE_SUCCESS;
2978 }
2979 
2980 void hfp_ag_set_subcriber_number_information(hfp_phone_number_t * numbers, int numbers_count){
2981     hfp_ag_subscriber_numbers = numbers;
2982     hfp_ag_subscriber_numbers_count = numbers_count;
2983 }
2984 
2985 void hfp_ag_clear_last_dialed_number(void){
2986     hfp_gsm_clear_last_dialed_number();
2987 }
2988 
2989 void hfp_ag_set_last_dialed_number(const char * number){
2990     hfp_gsm_set_last_dialed_number(number);
2991 }
2992 
2993 uint8_t hfp_ag_notify_incoming_call_waiting(hci_con_handle_t acl_handle){
2994     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2995     if (!hfp_connection){
2996         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2997     }
2998 
2999     if (!hfp_connection->call_waiting_notification_enabled){
3000         return ERROR_CODE_COMMAND_DISALLOWED;
3001     }
3002 
3003     hfp_connection->ag_notify_incoming_call_waiting = 1;
3004     hfp_ag_run_for_context(hfp_connection);
3005     return ERROR_CODE_SUCCESS;
3006 }
3007 
3008 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){
3009 	if (!name){
3010 		name = hfp_ag_default_service_name;
3011 	}
3012 	hfp_create_sdp_record(service, service_record_handle, BLUETOOTH_SERVICE_CLASS_HANDSFREE_AUDIO_GATEWAY, rfcomm_channel_nr, name);
3013 
3014 	/*
3015 	 * 0x01 – Ability to reject a call
3016 	 * 0x00 – No ability to reject a call
3017 	 */
3018 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0301);    // Hands-Free Profile - Network
3019 	de_add_number(service, DE_UINT, DE_SIZE_8, ability_to_reject_call);
3020 
3021 	// Construct SupportedFeatures for SDP bitmap:
3022 	//
3023 	// "The values of the “SupportedFeatures” bitmap given in Table 5.4 shall be the same as the values
3024 	//  of the Bits 0 to 4 of the unsolicited result code +BRSF"
3025 	//
3026 	// Wide band speech (bit 5) requires Codec negotiation
3027 	//
3028 	uint16_t sdp_features = supported_features & 0x1f;
3029 	if ( (wide_band_speech == 1) && (supported_features & (1 << HFP_AGSF_CODEC_NEGOTIATION))){
3030 		sdp_features |= 1 << 5;
3031 	}
3032 
3033     if (supported_features & (1 << HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS)){
3034         sdp_features |= 1 << 6;
3035     }
3036 
3037     if (supported_features & (1 << HFP_AGSF_VOICE_RECOGNITION_TEXT)){
3038         sdp_features |= 1 << 7;
3039     }
3040 
3041 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);    // Hands-Free Profile - SupportedFeatures
3042 	de_add_number(service, DE_UINT, DE_SIZE_16, sdp_features);
3043 }
3044 
3045 void hfp_ag_register_packet_handler(btstack_packet_handler_t callback){
3046 	btstack_assert(callback != NULL);
3047 
3048 	hfp_ag_callback = callback;
3049 	hfp_set_ag_callback(callback);
3050 }
3051