xref: /btstack/src/classic/hfp_ag.c (revision af7c3ae6cd1e2bcfd24e6d0654508ecf775c9e5d)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN
24  * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hfp_ag.c"
39 
40 // *****************************************************************************
41 //
42 // HFP Audio Gateway (AG) unit
43 //
44 // *****************************************************************************
45 
46 #include "btstack_config.h"
47 
48 #include <stdint.h>
49 #include <stdio.h>
50 #include <string.h>
51 
52 #include "hci_cmd.h"
53 #include "btstack_run_loop.h"
54 
55 #include "bluetooth_sdp.h"
56 #include "hci.h"
57 #include "btstack_memory.h"
58 #include "hci_dump.h"
59 #include "l2cap.h"
60 #include "btstack_debug.h"
61 #include "btstack_event.h"
62 #include "classic/core.h"
63 #include "classic/hfp.h"
64 #include "classic/hfp_ag.h"
65 #include "classic/hfp_gsm_model.h"
66 #include "classic/sdp_client_rfcomm.h"
67 #include "classic/sdp_server.h"
68 #include "classic/sdp_util.h"
69 
70 // private prototypes
71 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection);
72 static void hfp_ag_hf_start_ringing_incoming(hfp_connection_t * hfp_connection);
73 static void hfp_ag_hf_start_ringing_outgoing(hfp_connection_t * hfp_connection);
74 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection);
75 
76 // public prototypes
77 hfp_generic_status_indicator_t * get_hfp_generic_status_indicators(void);
78 int get_hfp_generic_status_indicators_nr(void);
79 void set_hfp_generic_status_indicators(hfp_generic_status_indicator_t * indicators, int indicator_nr);
80 void set_hfp_ag_indicators(hfp_ag_indicator_t * indicators, int indicator_nr);
81 int get_hfp_ag_indicators_nr(hfp_connection_t * context);
82 hfp_ag_indicator_t * get_hfp_ag_indicators(hfp_connection_t * context);
83 
84 #define HFP_SUBEVENT_INVALID 0xFFFF
85 
86 // const
87 static const char hfp_ag_default_service_name[] = "Voice gateway";
88 
89 // globals
90 
91 // higher layer callbacks
92 static btstack_packet_handler_t hfp_ag_callback;
93 
94 static 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 bool hfp_ag_response_and_hold_active = false;
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     uint8_t evra_enabled = hfp_connection->enhanced_voice_recognition_enabled ? 1 : 0;
523     snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, evra_enabled, hfp_connection->ag_vra_state);
524     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
525 }
526 
527 static int hfp_ag_send_voice_recognition_cmd(hfp_connection_t * hfp_connection, uint8_t activate_voice_recognition){
528     char buffer[30];
529     if (hfp_connection->enhanced_voice_recognition_enabled){
530         snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, activate_voice_recognition, hfp_connection->ag_vra_state);
531     } else {
532         snprintf(buffer, sizeof(buffer), "\r\n%s: %d\r\n", HFP_ACTIVATE_VOICE_RECOGNITION, activate_voice_recognition);
533     }
534     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
535 }
536 
537 static int hfp_ag_send_enhanced_voice_recognition_msg_cmd(hfp_connection_t * hfp_connection){
538     char buffer[HFP_VR_TEXT_HEADER_SIZE + HFP_MAX_VR_TEXT_SIZE];
539     snprintf(buffer, sizeof(buffer), "\r\n%s: 1,%d,%X,%d,%d,\"%s\"\r\n", HFP_ACTIVATE_VOICE_RECOGNITION,
540         hfp_connection->ag_vra_state,
541         hfp_connection->ag_msg.text_id,
542         hfp_connection->ag_msg.text_type,
543         hfp_connection->ag_msg.text_operation,
544         hfp_connection->ag_msg.text);
545     return send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
546 }
547 
548 static uint8_t hfp_ag_suggest_codec(hfp_connection_t *hfp_connection){
549     if (hfp_connection->sco_for_msbc_failed) return HFP_CODEC_CVSD;
550 
551     if (hfp_supports_codec(HFP_CODEC_MSBC, hfp_ag_codecs_nr, hfp_ag_codecs)){
552         if (hfp_supports_codec(HFP_CODEC_MSBC, hfp_connection->remote_codecs_nr, hfp_connection->remote_codecs)){
553             return HFP_CODEC_MSBC;
554         }
555     }
556     return HFP_CODEC_CVSD;
557 }
558 
559 /* state machines */
560 
561 static uint8_t hfp_ag_esco_s4_supported(hfp_connection_t * hfp_connection){
562     return (hfp_connection->remote_supported_features & (1<<HFP_HFSF_ESCO_S4)) &&  (hfp_ag_supported_features & (1 << HFP_AGSF_ESCO_S4));
563 }
564 
565 static int codecs_exchange_state_machine(hfp_connection_t * hfp_connection){
566     /* events ( == commands):
567         HFP_CMD_AVAILABLE_CODECS == received AT+BAC with list of codecs
568         HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP:
569             hf_trigger_codec_connection_setup == received BCC
570             ag_trigger_codec_connection_setup == received from AG to send BCS
571         HFP_CMD_HF_CONFIRMED_CODEC == received AT+BCS
572     */
573     switch (hfp_connection->codecs_state){
574         case HFP_CODECS_EXCHANGED:
575             if (hfp_connection->command == HFP_CMD_AVAILABLE_CODECS){
576                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
577                 return 1;
578             }
579             break;
580 
581         case HFP_CODECS_RECEIVED_TRIGGER_CODEC_EXCHANGE:
582         case HFP_CODECS_AG_RESEND_COMMON_CODEC:
583             hfp_connection->ag_send_common_codec = true;
584             break;
585         default:
586             break;
587     }
588 
589     if (hfp_connection->ag_send_common_codec){
590         hfp_connection->ag_send_common_codec = false;
591         hfp_connection->codecs_state = HFP_CODECS_AG_SENT_COMMON_CODEC;
592         hfp_connection->suggested_codec = hfp_ag_suggest_codec(hfp_connection);
593         hfp_ag_send_suggest_codec_cmd(hfp_connection->rfcomm_cid, hfp_connection->suggested_codec);
594         return 1;
595     }
596 
597     switch (hfp_connection->command){
598         case HFP_CMD_AVAILABLE_CODECS:
599             if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED){
600                 hfp_connection->codecs_state = HFP_CODECS_RECEIVED_LIST;
601                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
602                 return 1;
603             }
604 
605             switch (hfp_connection->codecs_state){
606                 case HFP_CODECS_AG_SENT_COMMON_CODEC:
607                     hfp_connection->codecs_state = HFP_CODECS_AG_RESEND_COMMON_CODEC;
608                     break;
609                 default:
610                     break;
611             }
612             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
613             return 1;
614 
615         case HFP_CMD_TRIGGER_CODEC_CONNECTION_SETUP:
616             hfp_connection->codecs_state = HFP_CODECS_RECEIVED_TRIGGER_CODEC_EXCHANGE;
617             hfp_connection->establish_audio_connection = 1;
618             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
619             return 1;
620 
621         case HFP_CMD_HF_CONFIRMED_CODEC:
622             if (hfp_connection->codec_confirmed != hfp_connection->suggested_codec){
623                 hfp_connection->codecs_state = HFP_CODECS_ERROR;
624                 hfp_ag_send_error(hfp_connection->rfcomm_cid);
625                 return 1;
626             }
627             hfp_connection->negotiated_codec = hfp_connection->codec_confirmed;
628             hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
629             log_info("hfp: codec confirmed: %s", (hfp_connection->negotiated_codec == HFP_CODEC_MSBC) ? "mSBC" : "CVSD");
630             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
631             // now, pick link settings
632             hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
633 #ifdef ENABLE_CC256X_ASSISTED_HFP
634             hfp_cc256x_prepare_for_sco(hfp_connection);
635 #endif
636 #ifdef ENABLE_RTK_PCM_WBS
637             hfp_connection->rtk_send_sco_config = true;
638 #endif
639             return 1;
640         default:
641             break;
642     }
643     return 0;
644 }
645 
646 static void hfp_ag_slc_established(hfp_connection_t * hfp_connection){
647     hfp_connection->state = HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED;
648     hfp_emit_slc_connection_event(hfp_connection, 0, hfp_connection->acl_handle, hfp_connection->remote_addr);
649 
650     // if active call exist, set per-hfp_connection state active, too (when audio is on)
651     if (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT){
652         hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
653     }
654     // if AG is ringing, also start ringing on the HF
655     if (hfp_gsm_call_status() == HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS){
656         switch (hfp_gsm_callsetup_status()){
657             case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
658                 hfp_ag_hf_start_ringing_incoming(hfp_connection);
659                 break;
660             case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
661                 hfp_ag_hf_start_ringing_outgoing(hfp_connection);
662                 break;
663             default:
664                 break;
665         }
666     }
667 }
668 
669 static int hfp_ag_run_for_context_service_level_connection(hfp_connection_t * hfp_connection){
670     // log_info("hfp_ag_run_for_context_service_level_connection state %u, command %u", hfp_connection->state, hfp_connection->command);
671     if (hfp_connection->state >= HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) return 0;
672     int sent = 0;
673     switch(hfp_connection->command){
674         case HFP_CMD_SUPPORTED_FEATURES:
675             switch(hfp_connection->state){
676                 case HFP_W4_EXCHANGE_SUPPORTED_FEATURES:
677                 case HFP_EXCHANGE_SUPPORTED_FEATURES:
678                     hfp_hf_drop_mSBC_if_eSCO_not_supported(hfp_ag_codecs, &hfp_ag_codecs_nr);
679                     if (has_codec_negotiation_feature(hfp_connection)){
680                         hfp_connection->state = HFP_W4_NOTIFY_ON_CODECS;
681                     } else {
682                         hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS;
683                     }
684                     hfp_ag_exchange_supported_features_cmd(hfp_connection->rfcomm_cid);
685                     return 1;
686                 default:
687                     break;
688             }
689             break;
690         case HFP_CMD_AVAILABLE_CODECS:
691             sent = codecs_exchange_state_machine(hfp_connection);
692             if (hfp_connection->codecs_state == HFP_CODECS_RECEIVED_LIST){
693                 hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS;
694             }
695             return sent;
696 
697         case HFP_CMD_RETRIEVE_AG_INDICATORS:
698             if (hfp_connection->state == HFP_W4_RETRIEVE_INDICATORS) {
699                 // HF requested AG Indicators and we did expect it
700                 hfp_connection->send_ag_indicators_segment = 0;
701                 hfp_connection->state = HFP_RETRIEVE_INDICATORS;
702                 // continue below in state switch
703             }
704             break;
705 
706         case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
707             if (hfp_connection->state != HFP_W4_RETRIEVE_INDICATORS_STATUS) break;
708             hfp_connection->state = HFP_W4_ENABLE_INDICATORS_STATUS_UPDATE;
709             hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
710             return 1;
711 
712         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
713             if (hfp_connection->state != HFP_W4_ENABLE_INDICATORS_STATUS_UPDATE) break;
714             if (has_call_waiting_and_3way_calling_feature(hfp_connection)){
715                 hfp_connection->state = HFP_W4_RETRIEVE_CAN_HOLD_CALL;
716             } else if (has_hf_indicators_feature(hfp_connection)){
717                 hfp_connection->state = HFP_W4_LIST_GENERIC_STATUS_INDICATORS;
718             } else {
719                 hfp_ag_slc_established(hfp_connection);
720             }
721             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
722             return 1;
723 
724         case HFP_CMD_SUPPORT_CALL_HOLD_AND_MULTIPARTY_SERVICES:
725             if (hfp_connection->state != HFP_W4_RETRIEVE_CAN_HOLD_CALL) break;
726             if (has_hf_indicators_feature(hfp_connection)){
727                 hfp_connection->state = HFP_W4_LIST_GENERIC_STATUS_INDICATORS;
728             }
729             hfp_ag_send_retrieve_can_hold_call_cmd(hfp_connection->rfcomm_cid);
730             if (!has_hf_indicators_feature(hfp_connection)){
731                 hfp_ag_slc_established(hfp_connection);
732             }
733             return 1;
734 
735         case HFP_CMD_LIST_GENERIC_STATUS_INDICATORS:
736             if (hfp_connection->state != HFP_W4_LIST_GENERIC_STATUS_INDICATORS) break;
737             hfp_connection->state = HFP_W4_RETRIEVE_GENERIC_STATUS_INDICATORS;
738             hfp_ag_send_list_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
739             return 1;
740 
741         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS:
742             if (hfp_connection->state != HFP_W4_RETRIEVE_GENERIC_STATUS_INDICATORS) break;
743             hfp_connection->state = HFP_W4_RETRIEVE_INITITAL_STATE_GENERIC_STATUS_INDICATORS;
744             hfp_ag_send_retrieve_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
745             return 1;
746 
747         case HFP_CMD_RETRIEVE_GENERIC_STATUS_INDICATORS_STATE:
748             if (hfp_connection->state != HFP_W4_RETRIEVE_INITITAL_STATE_GENERIC_STATUS_INDICATORS) break;
749             hfp_ag_slc_established(hfp_connection);
750             hfp_ag_send_retrieve_initital_supported_generic_status_indicators_cmd(hfp_connection->rfcomm_cid);
751             return 1;
752         default:
753             break;
754     }
755 
756     switch (hfp_connection->state){
757         case HFP_RETRIEVE_INDICATORS: {
758             int next_segment = hfp_ag_send_retrieve_indicators_cmd_via_generator(hfp_connection->rfcomm_cid, hfp_connection, hfp_connection->send_ag_indicators_segment);
759             int num_segments = hfp_ag_indicators_cmd_generator_num_segments(hfp_connection);
760             log_info("HFP_CMD_RETRIEVE_AG_INDICATORS next segment %u, num_segments %u", next_segment, num_segments);
761             if (next_segment < num_segments){
762                 // prepare sending of next segment
763                 hfp_connection->send_ag_indicators_segment = next_segment;
764                 log_info("HFP_CMD_RETRIEVE_AG_INDICATORS more. command %u, next seg %u", hfp_connection->command, next_segment);
765             } else {
766                 // done, go to next state
767                 hfp_connection->send_ag_indicators_segment = 0;
768                 hfp_connection->state = HFP_W4_RETRIEVE_INDICATORS_STATUS;
769             }
770             return 1;
771         }
772         default:
773             break;
774     }
775     return 0;
776 }
777 
778 static bool hfp_ag_vra_flag_supported(hfp_connection_t * hfp_connection){
779     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_VOICE_RECOGNITION_FUNCTION);
780     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_VOICE_RECOGNITION_FUNCTION);
781     return hf && ag;
782 }
783 
784 static bool hfp_ag_enhanced_vra_flag_supported(hfp_connection_t * hfp_connection){
785     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS);
786     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_ENHANCED_VOICE_RECOGNITION_STATUS);
787     return hf && ag;
788 }
789 
790 static bool hfp_ag_can_send_enhanced_vra_message_flag_supported(hfp_connection_t * hfp_connection){
791     int ag = get_bit(hfp_ag_supported_features, HFP_AGSF_VOICE_RECOGNITION_TEXT);
792     int hf = get_bit(hfp_connection->remote_supported_features, HFP_HFSF_VOICE_RECOGNITION_TEXT);
793     return hf && ag;
794 }
795 
796 static bool hfp_ag_can_activate_voice_recognition(hfp_connection_t * hfp_connection){
797     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED || hfp_connection->state > HFP_AUDIO_CONNECTION_ESTABLISHED){
798         return false;
799     }
800     if (hfp_connection->vra_state != HFP_VRA_VOICE_RECOGNITION_OFF){
801         return false;
802     }
803     if (hfp_connection->ag_vra_send_command){
804         return false;
805     }
806     return true;
807 }
808 
809 static bool hfp_ag_voice_recognition_session_active(hfp_connection_t * hfp_connection){
810     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED || hfp_connection->state > HFP_AUDIO_CONNECTION_ESTABLISHED){
811         return false;
812     }
813     if (hfp_connection->vra_state != HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
814         if (hfp_connection->vra_state == HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
815             return true;
816         }
817         return false;
818     }
819     return true;
820 }
821 
822 static bool hfp_ag_is_audio_connection_active(hfp_connection_t * hfp_connection){
823     switch (hfp_connection->state){
824         case HFP_W2_CONNECT_SCO:
825         case HFP_W4_SCO_CONNECTED:
826         case HFP_AUDIO_CONNECTION_ESTABLISHED:
827             return true;
828         default:
829             return false;
830     }
831 }
832 
833 static void hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection_t * hfp_connection, uint8_t status){
834     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
835 
836     uint8_t event[6];
837     event[0] = HCI_EVENT_HFP_META;
838     event[1] = sizeof(event) - 2;
839     event[2] = HFP_SUBEVENT_ENHANCED_VOICE_RECOGNITION_AG_MESSAGE_SENT;
840     little_endian_store_16(event, 3, acl_handle);
841     event[5] = status;
842     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
843 }
844 
845 
846 static void hfp_ag_emit_hf_indicator_value(hfp_connection_t * hfp_connection, uint16_t uuid, uint8_t value){
847     hci_con_handle_t acl_handle = (hfp_connection != NULL) ? hfp_connection->acl_handle : HCI_CON_HANDLE_INVALID;
848 
849     uint8_t event[8];
850     event[0] = HCI_EVENT_HFP_META;
851     event[1] = sizeof(event) - 2;
852     event[2] = HFP_SUBEVENT_HF_INDICATOR;
853     little_endian_store_16(event, 3, acl_handle);
854     little_endian_store_16(event, 5, uuid);
855     event[7] = value;
856     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
857 }
858 
859 static void hfp_ag_emit_general_simple_event(uint8_t event_subtype){
860     if (!hfp_ag_callback) return;
861 
862     uint8_t event[5];
863     event[0] = HCI_EVENT_HFP_META;
864     event[1] = sizeof(event) - 2;
865     event[2] = event_subtype;
866     little_endian_store_16(event, 3, HCI_CON_HANDLE_INVALID);
867     (*hfp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
868 }
869 
870 // @return status
871 static uint8_t hfp_ag_vra_state_machine_two(hfp_connection_t * hfp_connection){
872     uint8_t status = ERROR_CODE_SUCCESS;
873     switch (hfp_connection->vra_state_requested){
874         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO:
875             if (!hfp_ag_is_audio_connection_active(hfp_connection)){
876                 status = hfp_ag_setup_audio_connection(hfp_connection);
877                 if (status != ERROR_CODE_SUCCESS){
878                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
879                     hfp_emit_voice_recognition_enabled(hfp_connection, status);
880                     break;
881                 }
882             }
883             hfp_connection->enhanced_voice_recognition_enabled = true;
884             hfp_connection->vra_state = HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO;
885             hfp_connection->vra_state_requested = hfp_connection->vra_state;
886             hfp_emit_enhanced_voice_recognition_hf_ready_for_audio_event(hfp_connection, ERROR_CODE_SUCCESS);
887             break;
888 
889         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF:
890             hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_OFF;
891             hfp_connection->vra_state_requested = hfp_connection->vra_state;
892 
893             // release audio connection only if it was opened after audio VR activated
894             if (hfp_ag_is_audio_connection_active(hfp_connection) && !hfp_connection->ag_audio_connection_opened_before_vra){
895                 hfp_trigger_release_audio_connection(hfp_connection);
896             }
897 
898             hfp_emit_voice_recognition_disabled(hfp_connection, ERROR_CODE_SUCCESS);
899             break;
900 
901         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED:
902             // open only if audio connection does not already exist
903             if (!hfp_ag_is_audio_connection_active(hfp_connection)){
904                 status = hfp_ag_setup_audio_connection(hfp_connection);
905                 if (status != ERROR_CODE_SUCCESS){
906                     hfp_connection->vra_state_requested = hfp_connection->vra_state;
907                     hfp_emit_voice_recognition_enabled(hfp_connection, status);
908                     break;
909                 }
910             }
911 
912             hfp_connection->vra_state = HFP_VRA_VOICE_RECOGNITION_ACTIVATED;
913             hfp_connection->vra_state_requested = hfp_connection->vra_state;
914             hfp_connection->enhanced_voice_recognition_enabled = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
915 
916             if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
917                 hfp_emit_voice_recognition_enabled(hfp_connection, ERROR_CODE_SUCCESS);
918             } else {
919                 hfp_connection->emit_vra_enabled_after_audio_established = true;
920             }
921             break;
922 
923         default:
924             break;
925     }
926     return status;
927 }
928 
929 static uint8_t hfp_ag_vra_send_command(hfp_connection_t * hfp_connection){
930     uint8_t done = 0;
931     uint8_t status;
932 
933     switch (hfp_connection->vra_state_requested){
934         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG:
935             done = hfp_ag_send_enhanced_voice_recognition_msg_cmd(hfp_connection);
936             if (done == 0){
937                 hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection, ERROR_CODE_UNSPECIFIED_ERROR);
938             } else {
939                 hfp_ag_emit_enhanced_voice_recognition_msg_sent_event(hfp_connection, ERROR_CODE_SUCCESS);
940             }
941             hfp_connection->vra_state_requested = hfp_connection->vra_state;
942             return done;
943 
944         case HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS:
945             done = hfp_ag_send_enhanced_voice_recognition_state_cmd(hfp_connection);
946             if (done == 0){
947                 hfp_emit_enhanced_voice_recognition_state_event(hfp_connection, ERROR_CODE_UNSPECIFIED_ERROR);
948             } else {
949                 hfp_emit_enhanced_voice_recognition_state_event(hfp_connection, ERROR_CODE_SUCCESS);
950             }
951             hfp_connection->vra_state_requested = hfp_connection->vra_state;
952             return done;
953 
954         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED:
955         case HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF:
956             done = hfp_ag_send_voice_recognition_cmd(hfp_connection, hfp_connection->ag_activate_voice_recognition_value);
957             if (done == 0){
958                 hfp_connection->vra_state_requested = hfp_connection->vra_state;
959 
960                 if (hfp_connection->ag_activate_voice_recognition_value == 1){
961                     hfp_emit_voice_recognition_enabled(hfp_connection, done);
962                 } else {
963                     hfp_emit_voice_recognition_disabled(hfp_connection, done);
964                 }
965                 return 0;
966             }
967             status = hfp_ag_vra_state_machine_two(hfp_connection);
968             return (status == ERROR_CODE_SUCCESS) ? 1 : 0;
969 
970         default:
971             log_error("state %u", hfp_connection->vra_state_requested);
972             btstack_assert(false);
973             return 0;
974     }
975 }
976 
977 static int hfp_ag_voice_recognition_state_machine(hfp_connection_t * hfp_connection){
978     if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) {
979         return 0;
980     }
981     int done = 0;
982     uint8_t status;
983 
984     // VRA action initiated by AG
985     if (hfp_connection->ag_vra_send_command){
986         hfp_connection->ag_vra_send_command = false;
987         return hfp_ag_vra_send_command(hfp_connection);
988     }
989 
990     if (hfp_connection->ag_vra_requested_by_hf){
991         hfp_connection->ag_vra_requested_by_hf = false;
992 
993         // HF initiatied voice recognition, parser extracted activation value
994         switch (hfp_connection->ag_activate_voice_recognition_value){
995             case 0:
996                 if (hfp_ag_voice_recognition_session_active(hfp_connection)){
997                     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
998                     done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
999                 }
1000                 break;
1001 
1002                 case 1:
1003                     if (hfp_ag_can_activate_voice_recognition(hfp_connection)){
1004                         hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
1005                         done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1006                     }
1007                     break;
1008 
1009                     case 2:
1010                         if (hfp_ag_voice_recognition_session_active(hfp_connection)){
1011                             hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO;
1012                             done = hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1013                         }
1014                         break;
1015                         default:
1016                             break;
1017         }
1018         if (done == 0){
1019             hfp_connection->vra_state_requested = hfp_connection->vra_state;
1020             done = hfp_ag_send_error(hfp_connection->rfcomm_cid);
1021             return 1;
1022         }
1023 
1024         status = hfp_ag_vra_state_machine_two(hfp_connection);
1025         return (status == ERROR_CODE_SUCCESS) ? 1 : 0;
1026     }
1027 
1028     return 0;
1029 }
1030 
1031 static int hfp_ag_run_for_context_service_level_connection_queries(hfp_connection_t * hfp_connection){
1032     int sent = codecs_exchange_state_machine(hfp_connection);
1033     if (sent) return 1;
1034 
1035     if (hfp_connection->ag_send_in_band_ring_tone_setting){
1036         hfp_connection->ag_send_in_band_ring_tone_setting = false;
1037         hfp_ag_send_change_in_band_ring_tone_setting_cmd(hfp_connection->rfcomm_cid);
1038         return 1;
1039     }
1040 
1041     switch(hfp_connection->command){
1042         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME:
1043             hfp_ag_send_report_network_operator_name_cmd(hfp_connection->rfcomm_cid, hfp_connection->network_operator);
1044             return 1;
1045         case HFP_CMD_QUERY_OPERATOR_SELECTION_NAME_FORMAT:
1046             if (hfp_connection->network_operator.format != 0){
1047                 hfp_ag_send_error(hfp_connection->rfcomm_cid);
1048             } else {
1049                 hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1050             }
1051             return 1;
1052         case HFP_CMD_ENABLE_INDIVIDUAL_AG_INDICATOR_STATUS_UPDATE:
1053             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1054             return 1;
1055         case HFP_CMD_ENABLE_EXTENDED_AUDIO_GATEWAY_ERROR:
1056             if (hfp_connection->extended_audio_gateway_error){
1057                 hfp_connection->extended_audio_gateway_error = 0;
1058                 hfp_ag_send_report_extended_audio_gateway_error(hfp_connection->rfcomm_cid, hfp_connection->extended_audio_gateway_error_value);
1059                 return 1;
1060             }
1061             break;
1062         case HFP_CMD_ENABLE_INDICATOR_STATUS_UPDATE:
1063             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
1064             return 1;
1065         default:
1066             break;
1067     }
1068     return 0;
1069 }
1070 
1071 static int hfp_ag_run_for_audio_connection(hfp_connection_t * hfp_connection){
1072     if ((hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) ||
1073         (hfp_connection->state > HFP_W2_DISCONNECT_SCO)) return 0;
1074 
1075     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1076 
1077     if (hfp_connection->release_audio_connection){
1078         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
1079         hfp_connection->release_audio_connection = 0;
1080         gap_disconnect(hfp_connection->sco_handle);
1081         return 1;
1082     }
1083 
1084     // accept incoming audio connection (codec negotiation is not used)
1085     if (hfp_connection->accept_sco){
1086         // notify about codec selection if not done already
1087         if (hfp_connection->negotiated_codec == 0){
1088             hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
1089         }
1090         //
1091         bool incoming_eSCO = hfp_connection->accept_sco == 2;
1092         hfp_connection->accept_sco = 0;
1093         hfp_connection->state = HFP_W4_SCO_CONNECTED;
1094         hfp_accept_synchronous_connection(hfp_connection, incoming_eSCO);
1095         return 1;
1096     }
1097 
1098     // run codecs exchange
1099     int sent = codecs_exchange_state_machine(hfp_connection);
1100     if (sent) return 1;
1101 
1102     if (hfp_connection->codecs_state != HFP_CODECS_EXCHANGED) return 0;
1103     if (hfp_connection->establish_audio_connection){
1104         hfp_connection->state = HFP_W4_SCO_CONNECTED;
1105         hfp_connection->establish_audio_connection = 0;
1106         hfp_setup_synchronous_connection(hfp_connection);
1107         return 1;
1108     }
1109     return 0;
1110 }
1111 
1112 static void hfp_ag_set_callsetup_indicator(void){
1113     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("callsetup");
1114     if (!indicator){
1115         log_error("hfp_ag_set_callsetup_indicator: callsetup indicator is missing");
1116         return;
1117     };
1118     indicator->status = hfp_gsm_callsetup_status();
1119 }
1120 
1121 static void hfp_ag_set_callheld_indicator(void){
1122     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("callheld");
1123     if (!indicator){
1124         log_error("hfp_ag_set_callheld_state: callheld indicator is missing");
1125         return;
1126     };
1127     indicator->status = hfp_gsm_callheld_status();
1128 }
1129 
1130 //
1131 // transition implementations for hfp_ag_call_state_machine
1132 //
1133 
1134 static void hfp_ag_hf_start_ringing_incoming(hfp_connection_t * hfp_connection){
1135     if (use_in_band_tone()){
1136         hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING;
1137         hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1138     } else {
1139         hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1140     }
1141 }
1142 
1143 static void hfp_ag_hf_start_ringing_outgoing(hfp_connection_t * hfp_connection){
1144     hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1145 }
1146 
1147 static void hfp_ag_hf_stop_ringing(hfp_connection_t * hfp_connection){
1148     hfp_connection->ag_ring = 0;
1149     hfp_connection->ag_send_clip = 0;
1150 }
1151 
1152 
1153 static void hfp_ag_trigger_incoming_call_during_active_one(void){
1154     btstack_linked_list_iterator_t it;
1155     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1156     while (btstack_linked_list_iterator_has_next(&it)){
1157         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1158         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1159         if (hfp_connection->call_state != HFP_CALL_ACTIVE) continue;
1160 
1161         hfp_connection->call_state = HFP_CALL_W2_SEND_CALL_WAITING;
1162         hfp_ag_run_for_context(hfp_connection);
1163     }
1164 }
1165 
1166 static void hfp_ag_trigger_ring_and_clip(void) {
1167     btstack_linked_list_iterator_t it;
1168     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1169     while (btstack_linked_list_iterator_has_next(&it)){
1170         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1171         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1172         switch (hfp_connection->call_state){
1173             case HFP_CALL_INCOMING_RINGING:
1174             case HFP_CALL_OUTGOING_RINGING:
1175             case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1176                 // Queue RING on this connection
1177                 hfp_connection->ag_ring = 1;
1178 
1179                 // HFP v1.8, 4.23 Calling Line Identification (CLI) Notification
1180                 // "If the calling subscriber number information is available from the network, the AG shall issue the
1181                 // +CLIP unsolicited result code just after every RING indication when the HF is alerted in an incoming call."
1182                 hfp_connection->ag_send_clip = hfp_gsm_clip_type() && hfp_connection->clip_enabled;
1183 
1184                 // trigger next message
1185                 rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1186                 break;
1187             default:
1188                 break;
1189         }
1190     }
1191 }
1192 
1193 // trigger RING and CLIP messages on connections that are ringing
1194 static void hfp_ag_ring_timeout_handler(btstack_timer_source_t * timer){
1195     hfp_ag_trigger_ring_and_clip();
1196 
1197     btstack_run_loop_set_timer(timer, HFP_RING_PERIOD_MS); // 2 seconds timeout
1198     btstack_run_loop_add_timer(timer);
1199 }
1200 
1201 static void hfp_ag_ring_timeout_stop(void){
1202     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1203 }
1204 
1205 static void hfp_ag_start_ringing(void){
1206     // setup ring timer
1207     btstack_run_loop_remove_timer(&hfp_ag_ring_timeout);
1208     btstack_run_loop_set_timer_handler(&hfp_ag_ring_timeout, hfp_ag_ring_timeout_handler);
1209     btstack_run_loop_set_timer(&hfp_ag_ring_timeout, HFP_RING_PERIOD_MS); // 2 seconds timeout
1210     btstack_run_loop_add_timer(&hfp_ag_ring_timeout);
1211 
1212     // emit start ringing
1213     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_START_RINGING);
1214 
1215     // send initial RING + CLIP
1216     hfp_ag_trigger_ring_and_clip();
1217 }
1218 
1219 static void hfp_ag_stop_ringing(void){
1220     hfp_ag_ring_timeout_stop();
1221     hfp_ag_emit_general_simple_event(HFP_SUBEVENT_STOP_RINGING);
1222 
1223     btstack_linked_list_iterator_t it;
1224     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1225     while (btstack_linked_list_iterator_has_next(&it)){
1226         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1227         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1228         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1229             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1230         hfp_ag_hf_stop_ringing(hfp_connection);
1231     }
1232 }
1233 
1234 static void hfp_ag_trigger_incoming_call_idle(void){
1235     int indicator_index = get_ag_indicator_index_for_name("callsetup");
1236     if (indicator_index < 0) return;
1237 
1238     // update callsetup state in connections
1239     btstack_linked_list_iterator_t it;
1240     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1241     while (btstack_linked_list_iterator_has_next(&it)){
1242         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1243         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1244         if (hfp_connection->call_state != HFP_CALL_IDLE) continue;
1245 
1246         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1247 
1248         hfp_ag_hf_start_ringing_incoming(hfp_connection);
1249 
1250         hfp_ag_run_for_context(hfp_connection);
1251     }
1252 
1253     // start local ringing - started after connection state has been updated
1254     hfp_ag_start_ringing();
1255 }
1256 
1257 static void hfp_ag_trigger_outgoing_call(void){
1258     btstack_linked_list_iterator_t it;
1259     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1260     while (btstack_linked_list_iterator_has_next(&it)){
1261         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1262         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1263         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1264         if (hfp_connection->call_state == HFP_CALL_IDLE){
1265             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1266         }
1267     }
1268 }
1269 
1270 static void hfp_ag_handle_outgoing_call_accepted(hfp_connection_t * hfp_connection){
1271     hfp_connection->call_state = HFP_CALL_OUTGOING_DIALING;
1272 
1273     // trigger callsetup to be
1274     int put_call_on_hold = hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT;
1275     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ACCEPTED, 0, 0, NULL);
1276 
1277     int indicator_index ;
1278 
1279     hfp_ag_set_callsetup_indicator();
1280     indicator_index = get_ag_indicator_index_for_name("callsetup");
1281     hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1282 
1283     // put current call on hold if active
1284     if (put_call_on_hold){
1285         log_info("AG putting current call on hold for new outgoing call");
1286         hfp_ag_set_callheld_indicator();
1287         indicator_index = get_ag_indicator_index_for_name("callheld");
1288         hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[indicator_index]);
1289     }
1290 
1291     // start audio if needed
1292     hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1293 }
1294 
1295 static void hfp_ag_transfer_indicator(const char * name){
1296     int indicator_index = get_ag_indicator_index_for_name(name);
1297     if (indicator_index < 0) return;
1298 
1299     btstack_linked_list_iterator_t it;
1300     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1301     while (btstack_linked_list_iterator_has_next(&it)){
1302         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1303         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1304         hfp_ag_establish_service_level_connection(hfp_connection->remote_addr);
1305         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1306         hfp_ag_run_for_context(hfp_connection);
1307     }
1308 }
1309 
1310 static void hfp_ag_transfer_callsetup_state(void){
1311     hfp_ag_transfer_indicator("callsetup");
1312 }
1313 
1314 static void hfp_ag_transfer_call_state(void){
1315     hfp_ag_transfer_indicator("call");
1316 }
1317 
1318 static void hfp_ag_transfer_callheld_state(void){
1319     hfp_ag_transfer_indicator("callheld");
1320 }
1321 
1322 static void hfp_ag_hf_accept_call(hfp_connection_t * source){
1323     int call_indicator_index = get_ag_indicator_index_for_name("call");
1324     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1325 
1326     hfp_ag_stop_ringing();
1327 
1328     btstack_linked_list_iterator_t it;
1329     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1330     while (btstack_linked_list_iterator_has_next(&it)){
1331         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1332         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1333         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1334             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1335 
1336         if (hfp_connection == source){
1337 
1338             if (use_in_band_tone()){
1339                 hfp_connection->call_state = HFP_CALL_ACTIVE;
1340             } else {
1341                 hfp_connection->call_state = HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE;
1342                 hfp_ag_establish_audio_connection(hfp_connection->acl_handle);
1343             }
1344 
1345             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1346             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1347 
1348         } else {
1349             hfp_connection->call_state = HFP_CALL_IDLE;
1350         }
1351         hfp_ag_run_for_context(hfp_connection);
1352     }
1353 }
1354 
1355 static void hfp_ag_ag_accept_call(void){
1356     int call_indicator_index = get_ag_indicator_index_for_name("call");
1357     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1358 
1359     hfp_ag_stop_ringing();
1360 
1361     btstack_linked_list_iterator_t it;
1362     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1363     while (btstack_linked_list_iterator_has_next(&it)){
1364         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1365         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1366         if ((hfp_connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1367             (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1368 
1369         hfp_connection->call_state = HFP_CALL_TRIGGER_AUDIO_CONNECTION;
1370 
1371         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1372         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1373 
1374         hfp_ag_run_for_context(hfp_connection);
1375         break;  // only single
1376     }
1377 }
1378 
1379 static void hfp_ag_trigger_reject_call(void){
1380     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1381 
1382     hfp_ag_stop_ringing();
1383 
1384     btstack_linked_list_iterator_t it;
1385     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1386     while (btstack_linked_list_iterator_has_next(&it)){
1387         hfp_connection_t * connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1388         if (connection->local_role != HFP_ROLE_AG) continue;
1389         if ((connection->call_state != HFP_CALL_INCOMING_RINGING) &&
1390             (connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING)) continue;
1391 
1392         connection->call_state = HFP_CALL_IDLE;
1393         connection->ag_indicators_status_update_bitmap = store_bit(connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1394 
1395         if (connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1396             connection->release_audio_connection = 1;
1397         }
1398         hfp_emit_simple_event(connection, HFP_SUBEVENT_CALL_TERMINATED);
1399         hfp_ag_run_for_context(connection);
1400         rfcomm_request_can_send_now_event(connection->rfcomm_cid);
1401     }
1402 }
1403 
1404 static void hfp_ag_trigger_terminate_call(void){
1405     int call_indicator_index = get_ag_indicator_index_for_name("call");
1406 
1407     // no ringing during call
1408 
1409     btstack_linked_list_iterator_t it;
1410     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1411     while (btstack_linked_list_iterator_has_next(&it)){
1412         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1413         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1414         if (hfp_connection->call_state == HFP_CALL_IDLE) continue;
1415 
1416         hfp_connection->call_state = HFP_CALL_IDLE;
1417         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1418 
1419         if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
1420             hfp_connection->release_audio_connection = 1;
1421         }
1422 
1423         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_TERMINATED);
1424         hfp_ag_run_for_context(hfp_connection);
1425         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
1426     }
1427 }
1428 
1429 static void hfp_ag_set_call_indicator(void){
1430     hfp_ag_indicator_t * indicator = get_ag_indicator_for_name("call");
1431     if (!indicator){
1432         log_error("hfp_ag_set_call_state: call indicator is missing");
1433         return;
1434     };
1435     indicator->status = hfp_gsm_call_status();
1436 }
1437 
1438 static hfp_connection_t * hfp_ag_connection_for_call_state(hfp_call_state_t call_state){
1439     btstack_linked_list_iterator_t it;
1440     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1441     while (btstack_linked_list_iterator_has_next(&it)){
1442         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1443         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1444         if (hfp_connection->call_state == call_state) return hfp_connection;
1445     }
1446     return NULL;
1447 }
1448 
1449 static void hfp_ag_send_response_and_hold_state(hfp_response_and_hold_state_t state){
1450     btstack_linked_list_iterator_t it;
1451     btstack_linked_list_iterator_init(&it, hfp_get_connections());
1452     while (btstack_linked_list_iterator_has_next(&it)){
1453         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
1454         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
1455         hfp_connection->send_response_and_hold_status = state + 1;
1456     }
1457 }
1458 
1459 static int call_setup_state_machine(hfp_connection_t * hfp_connection){
1460     int indicator_index;
1461     switch (hfp_connection->call_state){
1462         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1463             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1464             // we got event: audio hfp_connection established
1465             hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1466             break;
1467         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE:
1468             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1469             // we got event: audio hfp_connection established
1470             hfp_connection->call_state = HFP_CALL_ACTIVE;
1471             break;
1472         case HFP_CALL_W2_SEND_CALL_WAITING:
1473             hfp_connection->call_state = HFP_CALL_W4_CHLD;
1474             hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
1475             indicator_index = get_ag_indicator_index_for_name("callsetup");
1476             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1477             break;
1478         default:
1479             break;
1480     }
1481     return 0;
1482 }
1483 
1484 // functions extracted from hfp_ag_call_sm below
1485 static void hfp_ag_handle_reject_outgoing_call(void){
1486     hfp_connection_t * hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1487     if (!hfp_connection){
1488         log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1489         return;
1490     }
1491 
1492     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_REJECTED, 0, 0, NULL);
1493     hfp_connection->call_state = HFP_CALL_IDLE;
1494     hfp_connection->send_error = 1;
1495     hfp_ag_run_for_context(hfp_connection);
1496 }
1497 
1498 // hfp_connection is used to identify originating HF
1499 static void hfp_ag_call_sm(hfp_ag_call_event_t event, hfp_connection_t * hfp_connection){
1500     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1501     int callheld_indicator_index = get_ag_indicator_index_for_name("callheld");
1502     int call_indicator_index = get_ag_indicator_index_for_name("call");
1503 
1504     switch (event){
1505         case HFP_AG_INCOMING_CALL:
1506             switch (hfp_gsm_call_status()){
1507                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1508                     switch (hfp_gsm_callsetup_status()){
1509                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1510                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1511                             hfp_ag_set_callsetup_indicator();
1512                             hfp_ag_trigger_incoming_call_idle();
1513                             log_info("AG rings");
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_NO_CALL_SETUP_IN_PROGRESS:
1522                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1523                             hfp_ag_set_callsetup_indicator();
1524                             hfp_ag_trigger_incoming_call_during_active_one();
1525                             log_info("AG call waiting");
1526                             break;
1527                         default:
1528                             break;
1529                     }
1530                     break;
1531                 default:
1532                     break;
1533             }
1534             break;
1535         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG:
1536             switch (hfp_gsm_call_status()){
1537                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1538                     switch (hfp_gsm_callsetup_status()){
1539                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1540                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1541                             hfp_ag_set_call_indicator();
1542                             hfp_ag_set_callsetup_indicator();
1543                             hfp_ag_ag_accept_call();
1544                             log_info("AG answers call, accept call by GSM");
1545                             break;
1546                         default:
1547                             break;
1548                     }
1549                     break;
1550                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1551                     switch (hfp_gsm_callsetup_status()){
1552                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1553                             log_info("AG: current call is placed on hold, incoming call gets active");
1554                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1555                             hfp_ag_set_callsetup_indicator();
1556                             hfp_ag_set_callheld_indicator();
1557                             hfp_ag_transfer_callsetup_state();
1558                             hfp_ag_transfer_callheld_state();
1559                             break;
1560                         default:
1561                             break;
1562                     }
1563                     break;
1564                 default:
1565                     break;
1566             }
1567             break;
1568 
1569         case HFP_AG_HELD_CALL_JOINED_BY_AG:
1570             switch (hfp_gsm_call_status()){
1571                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1572                     switch (hfp_gsm_callheld_status()){
1573                         case HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED:
1574                             log_info("AG: joining held call with active call");
1575                             hfp_gsm_handler(HFP_AG_HELD_CALL_JOINED_BY_AG, 0, 0, NULL);
1576                             hfp_ag_set_callheld_indicator();
1577                             hfp_ag_transfer_callheld_state();
1578                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1579                             break;
1580                         default:
1581                             break;
1582                     }
1583                     break;
1584                 default:
1585                     break;
1586             }
1587             break;
1588 
1589         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF:
1590             switch (hfp_gsm_call_status()){
1591                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1592                     switch (hfp_gsm_callsetup_status()){
1593                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1594                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, 0, 0, NULL);
1595                             hfp_ag_set_callsetup_indicator();
1596                             hfp_ag_set_call_indicator();
1597                             hfp_ag_hf_accept_call(hfp_connection);
1598                             hfp_connection->ok_pending = 1;
1599                             log_info("HF answers call, accept call by GSM");
1600                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1601                             break;
1602                         default:
1603                             break;
1604                     }
1605                     break;
1606                 default:
1607                     break;
1608             }
1609             break;
1610 
1611         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG:
1612             switch (hfp_gsm_call_status()){
1613                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1614                     switch (hfp_gsm_callsetup_status()){
1615                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1616                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, 0, 0, NULL);
1617                             hfp_ag_response_and_hold_active = true;
1618                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1619                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1620                             // as with regular call
1621                             hfp_ag_set_call_indicator();
1622                             hfp_ag_set_callsetup_indicator();
1623                             hfp_ag_ag_accept_call();
1624                             log_info("AG response and hold - hold by AG");
1625                             break;
1626                         default:
1627                             break;
1628                     }
1629                     break;
1630                 default:
1631                     break;
1632             }
1633             break;
1634 
1635         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF:
1636             switch (hfp_gsm_call_status()){
1637                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1638                     switch (hfp_gsm_callsetup_status()){
1639                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1640                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, 0, 0, NULL);
1641                             hfp_ag_response_and_hold_active = true;
1642                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1643                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1644                             // as with regular call
1645                             hfp_ag_set_call_indicator();
1646                             hfp_ag_set_callsetup_indicator();
1647                             hfp_ag_hf_accept_call(hfp_connection);
1648                             log_info("AG response and hold - hold by HF");
1649                             break;
1650                         default:
1651                             break;
1652                     }
1653                     break;
1654                 default:
1655                     break;
1656             }
1657             break;
1658 
1659         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG:
1660         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF:
1661             if (!hfp_ag_response_and_hold_active) break;
1662             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1663             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, 0, 0, NULL);
1664             hfp_ag_response_and_hold_active = false;
1665             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED;
1666             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1667             log_info("Held Call accepted and active");
1668             break;
1669 
1670         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG:
1671         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF:
1672             if (!hfp_ag_response_and_hold_active) break;
1673             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1674             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, 0, 0, NULL);
1675             hfp_ag_response_and_hold_active = false;
1676             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1677             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1678             // from terminate by ag
1679             hfp_ag_set_call_indicator();
1680             hfp_ag_trigger_terminate_call();
1681             break;
1682 
1683         case HFP_AG_TERMINATE_CALL_BY_HF:
1684             switch (hfp_gsm_call_status()){
1685                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1686                     switch (hfp_gsm_callsetup_status()){
1687                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1688                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1689                             hfp_ag_set_callsetup_indicator();
1690                             hfp_ag_transfer_callsetup_state();
1691                             hfp_ag_trigger_reject_call();
1692                             log_info("HF Rejected Incoming call, AG terminate call");
1693                             break;
1694                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1695                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1696                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1697                             hfp_ag_set_callsetup_indicator();
1698                             hfp_ag_transfer_callsetup_state();
1699                             log_info("AG terminate outgoing call process");
1700                             break;
1701                         default:
1702                             break;
1703                     }
1704                     break;
1705                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1706                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1707                     hfp_ag_set_callsetup_indicator();
1708                     hfp_ag_set_call_indicator();
1709                     hfp_ag_trigger_terminate_call();
1710                     log_info("AG terminate call");
1711                     break;
1712                 default:
1713                     break;
1714             }
1715             break;
1716 
1717         case HFP_AG_TERMINATE_CALL_BY_AG:
1718             switch (hfp_gsm_call_status()){
1719                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1720                     switch (hfp_gsm_callsetup_status()){
1721                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1722                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1723                             hfp_ag_set_callsetup_indicator();
1724                             hfp_ag_trigger_reject_call();
1725                             log_info("AG Rejected Incoming call, AG terminate call");
1726                             break;
1727                         default:
1728                             break;
1729                     }
1730                     break;
1731                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1732                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1733                     hfp_ag_set_callsetup_indicator();
1734                     hfp_ag_set_call_indicator();
1735                     hfp_ag_trigger_terminate_call();
1736                     log_info("AG terminate call");
1737                     break;
1738                 default:
1739                     break;
1740             }
1741             break;
1742         case HFP_AG_CALL_DROPPED:
1743             switch (hfp_gsm_call_status()){
1744                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1745                     switch (hfp_gsm_callsetup_status()){
1746                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1747                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1748                             hfp_ag_stop_ringing();
1749                             break;
1750                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1751                             log_info("Outgoing call interrupted\n");
1752                             break;
1753                         default:
1754                             break;
1755                     }
1756                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1757                     hfp_ag_set_callsetup_indicator();
1758                     hfp_ag_transfer_callsetup_state();
1759                     hfp_ag_trigger_terminate_call();
1760                     break;
1761                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1762                     if (hfp_ag_response_and_hold_active) {
1763                         hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1764                         hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1765                         hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1766                     }
1767                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1768                     hfp_ag_set_callsetup_indicator();
1769                     hfp_ag_set_call_indicator();
1770                     hfp_ag_trigger_terminate_call();
1771                     log_info("AG notify call dropped");
1772                     break;
1773                 default:
1774                     break;
1775             }
1776             break;
1777 
1778         case HFP_AG_OUTGOING_CALL_INITIATED_BY_HF:
1779             // directly reject call if number of free slots is exceeded
1780             if (!hfp_gsm_call_possible()){
1781                 hfp_connection->send_error = 1;
1782                 hfp_ag_run_for_context(hfp_connection);
1783                 break;
1784             }
1785 
1786             // note: number not used currently
1787             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, 0, 0, (const char *) &hfp_connection->line_buffer[3]);
1788 
1789             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1790 
1791             hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, (const char *) &hfp_connection->line_buffer[3]);
1792             break;
1793 
1794         case HFP_AG_OUTGOING_CALL_INITIATED_BY_AG:
1795             // directly reject call if number of free slots is exceeded
1796             if (!hfp_gsm_call_possible()) {
1797                 // TODO: no error for user
1798                 break;
1799             }
1800             switch (hfp_gsm_call_status()) {
1801                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1802                     switch (hfp_gsm_callsetup_status()) {
1803                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1804                             // note: number not used currently
1805                             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, 0, 0, "1234567");
1806                             // init call state for all connections
1807                             hfp_ag_trigger_outgoing_call();
1808                             // get first one and accept call
1809                             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1810                             if (hfp_connection) {
1811                                 hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1812                             }
1813                             break;
1814                         default:
1815                             // TODO: no error for user
1816                             break;
1817                     }
1818                     break;
1819                 default:
1820                     // TODO: no error for user
1821                     break;
1822             }
1823             break;
1824         case HFP_AG_OUTGOING_REDIAL_INITIATED:{
1825             // directly reject call if number of free slots is exceeded
1826             if (!hfp_gsm_call_possible()){
1827                 hfp_connection->send_error = 1;
1828                 hfp_ag_run_for_context(hfp_connection);
1829                 break;
1830             }
1831 
1832             hfp_gsm_handler(HFP_AG_OUTGOING_REDIAL_INITIATED, 0, 0, NULL);
1833             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1834 
1835             log_info("Redial last number");
1836             char * last_dialed_number = hfp_gsm_last_dialed_number();
1837 
1838             if (strlen(last_dialed_number) > 0){
1839                 log_info("Last number exists: accept call");
1840                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, last_dialed_number);
1841             } else {
1842                 log_info("log_infoLast number missing: reject call");
1843                 hfp_ag_handle_reject_outgoing_call();
1844             }
1845             break;
1846         }
1847         case HFP_AG_OUTGOING_CALL_REJECTED:
1848             hfp_ag_handle_reject_outgoing_call();
1849             break;
1850 
1851         case HFP_AG_OUTGOING_CALL_ACCEPTED:{
1852             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1853             if (!hfp_connection){
1854                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1855                 break;
1856             }
1857 
1858             hfp_connection->ok_pending = 1;
1859             hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1860             break;
1861         }
1862         case HFP_AG_OUTGOING_CALL_RINGING:
1863             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1864             if (!hfp_connection){
1865                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in dialing state");
1866                 break;
1867             }
1868 
1869             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_RINGING, 0, 0, NULL);
1870             hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1871             hfp_ag_set_callsetup_indicator();
1872             hfp_ag_transfer_callsetup_state();
1873             hfp_ag_hf_start_ringing_outgoing(hfp_connection);
1874             break;
1875 
1876         case HFP_AG_OUTGOING_CALL_ESTABLISHED:{
1877             // get outgoing call
1878             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_RINGING);
1879             if (!hfp_connection){
1880                 hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1881             }
1882             if (!hfp_connection){
1883                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection");
1884                 break;
1885             }
1886 
1887             bool callheld_status_call_on_hold_and_no_active_calls = hfp_gsm_callheld_status() == HFP_CALLHELD_STATUS_CALL_ON_HOLD_AND_NO_ACTIVE_CALLS;
1888             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ESTABLISHED, 0, 0, NULL);
1889             hfp_connection->call_state = HFP_CALL_ACTIVE;
1890             hfp_ag_set_callsetup_indicator();
1891             hfp_ag_set_call_indicator();
1892             hfp_ag_transfer_call_state();
1893             hfp_ag_transfer_callsetup_state();
1894             if (callheld_status_call_on_hold_and_no_active_calls){
1895                 hfp_ag_set_callheld_indicator();
1896                 hfp_ag_transfer_callheld_state();
1897             }
1898             hfp_ag_hf_stop_ringing(hfp_connection);
1899             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1900             break;
1901         }
1902 
1903         case HFP_AG_CALL_HOLD_USER_BUSY:
1904             hfp_gsm_handler(HFP_AG_CALL_HOLD_USER_BUSY, 0, 0, NULL);
1905             hfp_ag_set_callsetup_indicator();
1906             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1907             hfp_connection->call_state = HFP_CALL_ACTIVE;
1908             log_info("AG: Call Waiting, User Busy");
1909             break;
1910 
1911         case HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1912             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1913             int call_held = hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD;
1914 
1915             // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
1916             if (call_held || call_setup_in_progress){
1917                 hfp_gsm_handler(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index,
1918                                 0, NULL);
1919 
1920             }
1921 
1922             if (call_setup_in_progress){
1923                 log_info("AG: Call Dropped, Accept new call");
1924                 hfp_ag_set_callsetup_indicator();
1925                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1926             } else {
1927                 log_info("AG: Call Dropped, Resume held call");
1928             }
1929             if (call_held){
1930                 hfp_ag_set_callheld_indicator();
1931                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1932             }
1933 
1934             hfp_connection->call_state = HFP_CALL_ACTIVE;
1935             break;
1936         }
1937 
1938         case HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1939             // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
1940             // only update if callsetup changed
1941             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1942             hfp_gsm_handler(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index, 0,
1943                             NULL);
1944 
1945             if (call_setup_in_progress){
1946                 log_info("AG: Call on Hold, Accept new call");
1947                 hfp_ag_set_callsetup_indicator();
1948                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1949             } else {
1950                 log_info("AG: Swap calls");
1951             }
1952 
1953             hfp_ag_set_callheld_indicator();
1954             // hfp_ag_set_callheld_state(HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED);
1955             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1956             hfp_connection->call_state = HFP_CALL_ACTIVE;
1957             break;
1958         }
1959 
1960         case HFP_AG_CALL_HOLD_ADD_HELD_CALL:
1961             // Adds a held call to the conversation.
1962             if (hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD){
1963                 log_info("AG: Join 3-way-call");
1964                 hfp_gsm_handler(HFP_AG_CALL_HOLD_ADD_HELD_CALL, 0, 0, NULL);
1965                 hfp_ag_set_callheld_indicator();
1966                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1967                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1968             }
1969             hfp_connection->call_state = HFP_CALL_ACTIVE;
1970             break;
1971         case HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS:
1972             // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer)
1973             hfp_gsm_handler(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, 0, 0, NULL);
1974             log_info("AG: Transfer call -> Connect two calls and disconnect");
1975             hfp_ag_set_call_indicator();
1976             hfp_ag_set_callheld_indicator();
1977             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1978             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1979             hfp_connection->call_state = HFP_CALL_IDLE;
1980             break;
1981 
1982         default:
1983             break;
1984     }
1985 
1986 
1987 }
1988 
1989 
1990 static void hfp_ag_send_call_status(hfp_connection_t * hfp_connection, int call_index){
1991     hfp_gsm_call_t * active_call = hfp_gsm_call(call_index);
1992     if (!active_call) return;
1993 
1994     int idx = active_call->index;
1995     hfp_enhanced_call_dir_t dir = active_call->direction;
1996     hfp_enhanced_call_status_t status = active_call->enhanced_status;
1997     hfp_enhanced_call_mode_t mode = active_call->mode;
1998     hfp_enhanced_call_mpty_t mpty = active_call->mpty;
1999     uint8_t type = active_call->clip_type;
2000     char * number = active_call->clip_number;
2001 
2002     char buffer[100];
2003     // TODO: check length of a buffer, to fit the MTU
2004     int offset = snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d,%d,%d,%d", HFP_LIST_CURRENT_CALLS, idx, dir, status, mode, mpty);
2005     if (number){
2006         offset += snprintf(buffer+offset, sizeof(buffer)-offset-3, ", \"%s\",%u", number, type);
2007     }
2008     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n");
2009     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,
2010        mode, mpty, type, number);
2011     send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
2012 }
2013 
2014 // sends pending command, returns if command was sent
2015 static int hfp_ag_send_commands(hfp_connection_t *hfp_connection){
2016     if (hfp_connection->send_status_of_current_calls){
2017         hfp_connection->ok_pending = 0;
2018         if (hfp_connection->next_call_index < hfp_gsm_get_number_of_calls()){
2019             hfp_connection->next_call_index++;
2020             hfp_ag_send_call_status(hfp_connection, hfp_connection->next_call_index);
2021             return 1;
2022         } else {
2023             // 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
2024             hfp_connection->next_call_index = 0;
2025             hfp_connection->ok_pending = 1;
2026             hfp_connection->send_status_of_current_calls = 0;
2027         }
2028     }
2029 
2030     if (hfp_connection->ag_notify_incoming_call_waiting){
2031         hfp_connection->ag_notify_incoming_call_waiting = 0;
2032         hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
2033         return 1;
2034     }
2035 
2036     if (hfp_connection->send_error){
2037         hfp_connection->send_error = 0;
2038         hfp_connection->command = HFP_CMD_NONE;
2039         hfp_ag_send_error(hfp_connection->rfcomm_cid);
2040         return 1;
2041     }
2042 
2043     // note: before update AG indicators and ok_pending
2044     if (hfp_connection->send_response_and_hold_status){
2045         int status = hfp_connection->send_response_and_hold_status - 1;
2046         hfp_connection->send_response_and_hold_status = 0;
2047         hfp_ag_send_set_response_and_hold(hfp_connection->rfcomm_cid, status);
2048         return 1;
2049     }
2050 
2051     if (hfp_connection->ok_pending){
2052         hfp_connection->ok_pending = 0;
2053         hfp_connection->command = HFP_CMD_NONE;
2054         hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2055         return 1;
2056     }
2057 
2058     // update AG indicators
2059     if (hfp_connection->ag_indicators_status_update_bitmap){
2060         int i;
2061         for (i=0;i<hfp_connection->ag_indicators_nr;i++){
2062             if (get_bit(hfp_connection->ag_indicators_status_update_bitmap, i)){
2063                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, i, 0);
2064                 if (!hfp_connection->enable_status_update_for_ag_indicators) {
2065                     log_info("+CMER:3,0,0,0 - not sending update for '%s'", hfp_ag_indicators[i].name);
2066                     break;
2067                 }
2068                 hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[i]);
2069                 return 1;
2070             }
2071         }
2072     }
2073 
2074     if (hfp_connection->ag_send_no_carrier){
2075         hfp_connection->ag_send_no_carrier = false;
2076         hfp_ag_send_no_carrier(hfp_connection->rfcomm_cid);
2077         return 1;
2078     }
2079 
2080     // delay RING/CLIP until audio connection has been established for incoming calls
2081     // hfp_ag_hf_trigger_ring_and_clip is called in call_setup_state_machine
2082     if (hfp_connection->call_state != HFP_CALL_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING){
2083         if (hfp_connection->ag_ring){
2084             hfp_connection->ag_ring = 0;
2085             hfp_connection->command = HFP_CMD_NONE;
2086             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_RING);
2087             hfp_ag_send_ring(hfp_connection->rfcomm_cid);
2088             return 1;
2089         }
2090 
2091         if (hfp_connection->ag_send_clip){
2092             hfp_connection->ag_send_clip = 0;
2093             hfp_connection->command = HFP_CMD_NONE;
2094             hfp_ag_send_clip(hfp_connection->rfcomm_cid);
2095             return 1;
2096         }
2097     }
2098 
2099     if (hfp_connection->send_phone_number_for_voice_tag){
2100         hfp_connection->send_phone_number_for_voice_tag = 0;
2101         hfp_connection->command = HFP_CMD_NONE;
2102         hfp_connection->ok_pending = 1;
2103         hfp_ag_send_phone_number_for_voice_tag_cmd(hfp_connection->rfcomm_cid);
2104         return 1;
2105     }
2106 
2107     if (hfp_connection->send_subscriber_number){
2108         if (hfp_connection->next_subscriber_number_to_send < hfp_ag_subscriber_numbers_count){
2109             hfp_phone_number_t phone = hfp_ag_subscriber_numbers[hfp_connection->next_subscriber_number_to_send++];
2110             hfp_send_subscriber_number_cmd(hfp_connection->rfcomm_cid, phone.type, phone.number);
2111         } else {
2112             hfp_connection->send_subscriber_number = 0;
2113             hfp_connection->next_subscriber_number_to_send = 0;
2114             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2115         }
2116         hfp_connection->command = HFP_CMD_NONE;
2117         return 1;
2118     }
2119 
2120     if (hfp_connection->send_microphone_gain){
2121         hfp_connection->send_microphone_gain = 0;
2122         hfp_connection->command = HFP_CMD_NONE;
2123         hfp_ag_send_set_microphone_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->microphone_gain);
2124         return 1;
2125     }
2126 
2127     if (hfp_connection->send_speaker_gain){
2128         hfp_connection->send_speaker_gain = 0;
2129         hfp_connection->command = HFP_CMD_NONE;
2130         hfp_ag_send_set_speaker_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->speaker_gain);
2131         return 1;
2132     }
2133 
2134     if (hfp_connection->send_ag_status_indicators){
2135         hfp_connection->send_ag_status_indicators = 0;
2136         hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
2137         return 1;
2138     }
2139 
2140     return 0;
2141 }
2142 
2143 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection){
2144 
2145 	btstack_assert(hfp_connection != NULL);
2146 	btstack_assert(hfp_connection->local_role == HFP_ROLE_AG);
2147 
2148 	// during SDP query, RFCOMM CID is not set
2149 	if (hfp_connection->rfcomm_cid == 0) return;
2150 
2151     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED && hfp_connection->emit_vra_enabled_after_audio_established){
2152         hfp_connection->emit_vra_enabled_after_audio_established = false;
2153         hfp_emit_voice_recognition_enabled(hfp_connection, ERROR_CODE_SUCCESS);
2154     }
2155 
2156     // assert command could be sent
2157     if (hci_can_send_command_packet_now() == 0) return;
2158 
2159     if ((hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) && hfp_connection->release_audio_connection){
2160         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
2161         hfp_connection->release_audio_connection = 0;
2162         gap_disconnect(hfp_connection->sco_handle);
2163         return;
2164     }
2165 
2166 #ifdef ENABLE_CC256X_ASSISTED_HFP
2167     // WBS Disassociate
2168     if (hfp_connection->cc256x_send_wbs_disassociate){
2169         hfp_connection->cc256x_send_wbs_disassociate = false;
2170         hci_send_cmd(&hci_ti_wbs_disassociate);
2171         return;
2172     }
2173     // Write Codec Config
2174     if (hfp_connection->cc256x_send_write_codec_config){
2175         hfp_connection->cc256x_send_write_codec_config = false;
2176         hfp_cc256x_write_codec_config(hfp_connection);
2177         return;
2178     }
2179     // WBS Associate
2180     if (hfp_connection->cc256x_send_wbs_associate){
2181         hfp_connection->cc256x_send_wbs_associate = false;
2182         hci_send_cmd(&hci_ti_wbs_associate, hfp_connection->acl_handle);
2183         return;
2184     }
2185 #endif
2186 #ifdef ENABLE_BCM_PCM_WBS
2187     // Enable WBS
2188     if (hfp_connection->bcm_send_enable_wbs){
2189         hfp_connection->bcm_send_enable_wbs = false;
2190         hci_send_cmd(&hci_bcm_enable_wbs, 1, 2);
2191         return;
2192     }
2193     // Write I2S/PCM params
2194     if (hfp_connection->bcm_send_write_i2spcm_interface_param){
2195         hfp_connection->bcm_send_write_i2spcm_interface_param = false;
2196         hfp_bcm_write_i2spcm_interface_param(hfp_connection);
2197         return;
2198     }
2199     // Disable WBS
2200     if (hfp_connection->bcm_send_disable_wbs){
2201         hfp_connection->bcm_send_disable_wbs = false;
2202         hci_send_cmd(&hci_bcm_enable_wbs, 0, 2);
2203         return;
2204     }
2205 #endif
2206 #ifdef ENABLE_RTK_PCM_WBS
2207     // Configure CVSD vs. mSBC
2208     if (hfp_connection->rtk_send_sco_config){
2209         hfp_connection->rtk_send_sco_config = false;
2210         if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
2211             log_info("RTK SCO: 16k + mSBC");
2212             hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x00, 0x00, 0x41);
2213         } else {
2214             log_info("RTK SCO: 16k + CVSD");
2215             hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x0c, 0x00, 0x01);
2216         }
2217         return;
2218     }
2219 #endif
2220 #if defined (ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
2221     if (hfp_connection->state == HFP_W4_WBS_SHUTDOWN){
2222         hfp_finalize_connection_context(hfp_connection);
2223         return;
2224     }
2225 #endif
2226 
2227     if (!rfcomm_can_send_packet_now(hfp_connection->rfcomm_cid)) {
2228         log_info("hfp_ag_run_for_context: request can send for 0x%02x", hfp_connection->rfcomm_cid);
2229         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2230         return;
2231     }
2232 
2233     int cmd_sent = hfp_ag_send_commands(hfp_connection);
2234 
2235     if (!cmd_sent){
2236         cmd_sent = hfp_ag_run_for_context_service_level_connection(hfp_connection);
2237     }
2238 
2239     if (!cmd_sent){
2240         cmd_sent = hfp_ag_run_for_context_service_level_connection_queries(hfp_connection);
2241     }
2242 
2243     if (!cmd_sent){
2244         cmd_sent = call_setup_state_machine(hfp_connection);
2245     }
2246 
2247     if (!cmd_sent){
2248         cmd_sent = hfp_ag_run_for_audio_connection(hfp_connection);
2249     }
2250 
2251     if (!cmd_sent){
2252         cmd_sent = hfp_ag_voice_recognition_state_machine(hfp_connection);
2253     }
2254 
2255     // disconnect
2256     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && (hfp_connection->state == HFP_W2_DISCONNECT_RFCOMM)){
2257         hfp_connection->state = HFP_W4_RFCOMM_DISCONNECTED;
2258         rfcomm_disconnect(hfp_connection->rfcomm_cid);
2259     }
2260 
2261     if (cmd_sent){
2262         hfp_connection->command = HFP_CMD_NONE;
2263         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2264     }
2265 }
2266 
2267 static int hfp_parser_is_end_of_line(uint8_t byte){
2268     return (byte == '\n') || (byte == '\r');
2269 }
2270 
2271 static void hfp_ag_handle_rfcomm_data(hfp_connection_t * hfp_connection, uint8_t *packet, uint16_t size){
2272     // assertion: size >= 1 as rfcomm.c does not deliver empty packets
2273     if (size < 1) return;
2274     uint8_t status = ERROR_CODE_SUCCESS;
2275 
2276     hfp_log_rfcomm_message("HFP_AG_RX", packet, size);
2277 #ifdef ENABLE_HFP_AT_MESSAGES
2278     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_RECEIVED, (char *) packet);
2279 #endif
2280 
2281     // process messages byte-wise
2282     int pos;
2283     for (pos = 0; pos < size ; pos++){
2284         hfp_parse(hfp_connection, packet[pos], 0);
2285 
2286         // parse until end of line
2287         if (!hfp_parser_is_end_of_line(packet[pos])) continue;
2288 
2289         hfp_generic_status_indicator_t * indicator;
2290         switch(hfp_connection->command){
2291             case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
2292                 hfp_connection->command = HFP_CMD_NONE;
2293                 hfp_connection->ag_vra_requested_by_hf = true;
2294                 break;
2295             case HFP_CMD_RESPONSE_AND_HOLD_QUERY:
2296                 hfp_connection->command = HFP_CMD_NONE;
2297                 if (hfp_ag_response_and_hold_active){
2298                     hfp_connection->send_response_and_hold_status = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD + 1;
2299                 }
2300                 hfp_connection->ok_pending = 1;
2301                 break;
2302             case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
2303                 hfp_connection->command = HFP_CMD_NONE;
2304                 switch(hfp_connection->ag_response_and_hold_action){
2305                     case HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD:
2306                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, hfp_connection);
2307                         break;
2308                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED:
2309                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF, hfp_connection);
2310                         break;
2311                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED:
2312                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF, hfp_connection);
2313                         break;
2314                     default:
2315                         break;
2316                 }
2317                 hfp_connection->ok_pending = 1;
2318                 break;
2319             case HFP_CMD_HF_INDICATOR_STATUS:
2320                 hfp_connection->command = HFP_CMD_NONE;
2321 
2322                 if (hfp_connection->parser_indicator_index < hfp_ag_generic_status_indicators_nr){
2323                     indicator = &hfp_ag_generic_status_indicators[hfp_connection->parser_indicator_index];
2324                     switch (indicator->uuid){
2325                         case HFP_HF_INDICATOR_UUID_ENHANCED_SAFETY:
2326                             if (hfp_connection->parser_indicator_value > 1) {
2327                                 hfp_connection->send_error = 1;
2328                                 break;
2329                             }
2330                             hfp_connection->ok_pending = 1;
2331                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2332                             break;
2333                         case HFP_HF_INDICATOR_UUID_BATTERY_LEVEL:
2334                             if (hfp_connection->parser_indicator_value > 100){
2335                                 hfp_connection->send_error = 1;
2336                                 break;
2337                             }
2338                             hfp_connection->ok_pending = 1;
2339                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2340                             break;
2341                         default:
2342                             hfp_connection->send_error = 1;
2343                             break;
2344                     }
2345                 } else {
2346                     hfp_connection->send_error = 1;
2347                 }
2348                 break;
2349             case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
2350                 // expected by SLC state machine
2351                 if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) break;
2352                 hfp_connection->send_ag_indicators_segment = 0;
2353                 hfp_connection->send_ag_status_indicators = 1;
2354                 break;
2355             case HFP_CMD_LIST_CURRENT_CALLS:
2356                 hfp_connection->command = HFP_CMD_NONE;
2357                 hfp_connection->next_call_index = 0;
2358                 hfp_connection->send_status_of_current_calls = 1;
2359                 break;
2360             case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
2361                 hfp_connection->command = HFP_CMD_NONE;
2362                 if (hfp_ag_subscriber_numbers_count == 0){
2363                     hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2364                     break;
2365                 }
2366                 hfp_connection->next_subscriber_number_to_send = 0;
2367                 hfp_connection->send_subscriber_number = 1;
2368                 break;
2369             case HFP_CMD_TRANSMIT_DTMF_CODES:
2370             {
2371                 hfp_connection->command = HFP_CMD_NONE;
2372                 char buffer[2];
2373                 buffer[0] = (char) hfp_connection->ag_dtmf_code;
2374                 buffer[1] = 0;
2375                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_TRANSMIT_DTMF_CODES, buffer);
2376                 break;
2377             }
2378             case HFP_CMD_HF_REQUEST_PHONE_NUMBER:
2379                 hfp_connection->command = HFP_CMD_NONE;
2380                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_ATTACH_NUMBER_TO_VOICE_TAG);
2381                 break;
2382             case HFP_CMD_TURN_OFF_EC_AND_NR:
2383                 hfp_connection->command = HFP_CMD_NONE;
2384 
2385                 if (get_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION)){
2386                     hfp_connection->ok_pending = 1;
2387                     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION, hfp_connection->ag_echo_and_noise_reduction);
2388                     status = ERROR_CODE_SUCCESS;
2389                 } else {
2390                     hfp_connection->send_error = 1;
2391                     status = ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2392                 }
2393                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_ECHO_CANCELING_AND_NOISE_REDUCTION_DEACTIVATE, status);
2394                 break;
2395             case HFP_CMD_CALL_ANSWERED:
2396                 hfp_connection->command = HFP_CMD_NONE;
2397                 log_info("HFP: ATA");
2398                 hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, hfp_connection);
2399                 break;
2400             case HFP_CMD_HANG_UP_CALL:
2401                 hfp_connection->command = HFP_CMD_NONE;
2402                 hfp_connection->ok_pending = 1;
2403                 hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_HF, hfp_connection);
2404                 break;
2405             case HFP_CMD_CALL_HOLD: {
2406                 hfp_connection->command = HFP_CMD_NONE;
2407                 hfp_connection->ok_pending = 1;
2408 
2409                 switch (hfp_connection->ag_call_hold_action){
2410                     case 0:
2411                         // Releases all held calls or sets User Determined User Busy (UDUB) for a waiting call.
2412                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_USER_BUSY, hfp_connection);
2413                         break;
2414                     case 1:
2415                         // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
2416                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2417                         // waiting call (i.e., not to the held call) in conflicting situation.
2418                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2419                         break;
2420                     case 2:
2421                         // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
2422                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2423                         // waiting call (i.e., not to the held call) in conflicting situation.
2424                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2425                         break;
2426                     case 3:
2427                         // Adds a held call to the conversation.
2428                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_ADD_HELD_CALL, hfp_connection);
2429                         break;
2430                     case 4:
2431                         // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer).
2432                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, hfp_connection);
2433                         break;
2434                     default:
2435                         break;
2436                 }
2437 				hfp_connection->call_index = 0;
2438                 break;
2439             }
2440             case HFP_CMD_CALL_PHONE_NUMBER:
2441                 hfp_connection->command = HFP_CMD_NONE;
2442                 hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, hfp_connection);
2443                 break;
2444             case HFP_CMD_REDIAL_LAST_NUMBER:
2445                 hfp_connection->command = HFP_CMD_NONE;
2446                 hfp_ag_call_sm(HFP_AG_OUTGOING_REDIAL_INITIATED, hfp_connection);
2447                 break;
2448             case HFP_CMD_ENABLE_CLIP:
2449                 hfp_connection->command = HFP_CMD_NONE;
2450                 log_info("hfp: clip set, now: %u", hfp_connection->clip_enabled);
2451                 hfp_connection->ok_pending = 1;
2452                 break;
2453             case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
2454                 hfp_connection->command = HFP_CMD_NONE;
2455                 log_info("hfp: call waiting notification set, now: %u", hfp_connection->call_waiting_notification_enabled);
2456                 hfp_connection->ok_pending = 1;
2457                 break;
2458             case HFP_CMD_SET_SPEAKER_GAIN:
2459                 hfp_connection->command = HFP_CMD_NONE;
2460                 hfp_connection->ok_pending = 1;
2461                 log_info("HF speaker gain = %u", hfp_connection->speaker_gain);
2462                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_SPEAKER_VOLUME, hfp_connection->speaker_gain);
2463                 break;
2464             case HFP_CMD_SET_MICROPHONE_GAIN:
2465                 hfp_connection->command = HFP_CMD_NONE;
2466                 hfp_connection->ok_pending = 1;
2467                 log_info("HF microphone gain = %u", hfp_connection->microphone_gain);
2468                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_MICROPHONE_VOLUME, hfp_connection->microphone_gain);
2469                 break;
2470             case HFP_CMD_UNKNOWN:
2471                 hfp_connection->command = HFP_CMD_NONE;
2472                 hfp_connection->send_error = 1;
2473                 break;
2474             default:
2475                 break;
2476         }
2477     }
2478 }
2479 
2480 static void hfp_ag_run(void){
2481     btstack_linked_list_iterator_t it;
2482     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2483     while (btstack_linked_list_iterator_has_next(&it)){
2484         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2485         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2486         hfp_ag_run_for_context(hfp_connection);
2487     }
2488 }
2489 
2490 static void hfp_ag_rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2491     hfp_connection_t * hfp_connection = NULL;
2492     switch (packet_type){
2493         case RFCOMM_DATA_PACKET:
2494             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(channel);
2495             btstack_assert(hfp_connection != NULL);
2496 
2497             hfp_ag_handle_rfcomm_data(hfp_connection, packet, size);
2498             hfp_ag_run_for_context(hfp_connection);
2499             return;
2500         case HCI_EVENT_PACKET:
2501             if (packet[0] == RFCOMM_EVENT_CAN_SEND_NOW){
2502                 uint16_t rfcomm_cid = rfcomm_event_can_send_now_get_rfcomm_cid(packet);
2503                 hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
2504                 btstack_assert(hfp_connection != NULL);
2505 
2506                 hfp_ag_run_for_context(hfp_connection);
2507                 return;
2508             }
2509             hfp_handle_rfcomm_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2510             break;
2511         default:
2512             break;
2513     }
2514 
2515     hfp_ag_run();
2516 }
2517 
2518 static void hfp_ag_hci_event_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2519     hfp_handle_hci_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2520     hfp_ag_run();
2521 }
2522 
2523 void hfp_ag_init_codecs(int codecs_nr, const uint8_t * codecs){
2524     if (codecs_nr > HFP_MAX_NUM_CODECS){
2525         log_error("hfp_init: codecs_nr (%d) > HFP_MAX_NUM_CODECS (%d)", codecs_nr, HFP_MAX_NUM_CODECS);
2526         return;
2527     }
2528     int i;
2529     hfp_ag_codecs_nr = codecs_nr;
2530     for (i=0; i < codecs_nr; i++){
2531         hfp_ag_codecs[i] = codecs[i];
2532     }
2533 }
2534 
2535 void hfp_ag_init_supported_features(uint32_t supported_features){
2536     hfp_ag_supported_features = supported_features;
2537 }
2538 
2539 void hfp_ag_init_ag_indicators(int ag_indicators_nr, const hfp_ag_indicator_t * ag_indicators){
2540     hfp_ag_indicators_nr = ag_indicators_nr;
2541     (void)memcpy(hfp_ag_indicators, ag_indicators,
2542                  ag_indicators_nr * sizeof(hfp_ag_indicator_t));
2543 }
2544 
2545 void hfp_ag_init_hf_indicators(int hf_indicators_nr, const hfp_generic_status_indicator_t * hf_indicators){
2546     if (hf_indicators_nr > HFP_MAX_NUM_INDICATORS) return;
2547     hfp_ag_generic_status_indicators_nr = hf_indicators_nr;
2548     (void)memcpy(hfp_ag_generic_status_indicators, hf_indicators,
2549                  hf_indicators_nr * sizeof(hfp_generic_status_indicator_t));
2550 }
2551 
2552 void hfp_ag_init_call_hold_services(int call_hold_services_nr, const char * call_hold_services[]){
2553     hfp_ag_call_hold_services_nr = call_hold_services_nr;
2554     (void)memcpy(hfp_ag_call_hold_services, call_hold_services,
2555                  call_hold_services_nr * sizeof(char *));
2556 }
2557 
2558 
2559 void hfp_ag_init(uint16_t rfcomm_channel_nr){
2560 
2561     hfp_init();
2562     hfp_ag_call_hold_services_nr = 0;
2563     hfp_ag_response_and_hold_active = false;
2564     hfp_ag_indicators_nr = 0;
2565     hfp_ag_codecs_nr = 0;
2566     hfp_ag_supported_features = HFP_DEFAULT_AG_SUPPORTED_FEATURES;
2567     hfp_ag_subscriber_numbers = NULL;
2568     hfp_ag_subscriber_numbers_count = 0;
2569 
2570     hfp_ag_hci_event_callback_registration.callback = &hfp_ag_hci_event_packet_handler;
2571     hci_add_event_handler(&hfp_ag_hci_event_callback_registration);
2572 
2573     rfcomm_register_service(&hfp_ag_rfcomm_packet_handler, rfcomm_channel_nr, 0xffff);
2574 
2575     // used to set packet handler for outgoing rfcomm connections - could be handled by emitting an event to us
2576     hfp_set_ag_rfcomm_packet_handler(&hfp_ag_rfcomm_packet_handler);
2577 
2578     hfp_gsm_init();
2579 }
2580 
2581 void hfp_ag_deinit(void){
2582     hfp_deinit();
2583     hfp_gsm_deinit();
2584 
2585     hfp_ag_callback = NULL;
2586     hfp_ag_supported_features = 0;
2587     hfp_ag_codecs_nr = 0;
2588     hfp_ag_indicators_nr = 0;
2589     hfp_ag_call_hold_services_nr = 0;
2590     (void) memset(&hfp_ag_call_hold_services, 0, sizeof(hfp_ag_call_hold_services));
2591     hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
2592     (void) memset(&hfp_ag_response_and_hold_state, 0, sizeof(hfp_response_and_hold_state_t));
2593     hfp_ag_subscriber_numbers = NULL;
2594     (void) memset(&hfp_ag_hci_event_callback_registration, 0, sizeof(btstack_packet_callback_registration_t));
2595 }
2596 
2597 uint8_t hfp_ag_establish_service_level_connection(bd_addr_t bd_addr){
2598     return hfp_establish_service_level_connection(bd_addr, BLUETOOTH_SERVICE_CLASS_HANDSFREE, HFP_ROLE_AG);
2599 }
2600 
2601 uint8_t hfp_ag_release_service_level_connection(hci_con_handle_t acl_handle){
2602     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2603     if (!hfp_connection){
2604         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2605     }
2606 
2607     hfp_trigger_release_service_level_connection(hfp_connection);
2608     hfp_ag_run_for_context(hfp_connection);
2609     return ERROR_CODE_SUCCESS;
2610 }
2611 
2612 uint8_t hfp_ag_report_extended_audio_gateway_error_result_code(hci_con_handle_t acl_handle, hfp_cme_error_t error){
2613     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2614     if (!hfp_connection){
2615         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2616     }
2617 
2618     hfp_connection->extended_audio_gateway_error = 0;
2619     if (!hfp_connection->enable_extended_audio_gateway_error_report){
2620         return ERROR_CODE_COMMAND_DISALLOWED;
2621     }
2622 
2623     hfp_connection->extended_audio_gateway_error = error;
2624     hfp_ag_run_for_context(hfp_connection);
2625     return ERROR_CODE_SUCCESS;
2626 }
2627 
2628 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection){
2629     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
2630         return ERROR_CODE_COMMAND_DISALLOWED;
2631     }
2632     if (hfp_connection->state >= HFP_W2_DISCONNECT_SCO){
2633         return ERROR_CODE_COMMAND_DISALLOWED;
2634     }
2635 
2636     hfp_connection->establish_audio_connection = 1;
2637     if (!has_codec_negotiation_feature(hfp_connection)){
2638         log_info("hfp_ag_establish_audio_connection - no codec negotiation feature, using CVSD");
2639         hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
2640         hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
2641         // now, pick link settings
2642         hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
2643 #ifdef ENABLE_CC256X_ASSISTED_HFP
2644         hfp_cc256x_prepare_for_sco(hfp_connection);
2645 #endif
2646         return ERROR_CODE_SUCCESS;
2647     }
2648 
2649     uint8_t i;
2650     bool codec_was_in_use = false;
2651     bool better_codec_can_be_used = false;
2652 
2653     for (i = 0; i<hfp_connection->remote_codecs_nr; i++){
2654         if (hfp_connection->negotiated_codec == hfp_connection->remote_codecs[i]){
2655             codec_was_in_use = true;
2656         } else if (hfp_connection->negotiated_codec < hfp_connection->remote_codecs[i]){
2657             better_codec_can_be_used = true;
2658         }
2659     }
2660 
2661     if (!codec_was_in_use || better_codec_can_be_used){
2662         hfp_connection->ag_send_common_codec = true;
2663         hfp_connection->codecs_state = HFP_CODECS_IDLE;
2664     }
2665     return ERROR_CODE_SUCCESS;
2666 }
2667 
2668 uint8_t hfp_ag_establish_audio_connection(hci_con_handle_t acl_handle){
2669     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2670     if (!hfp_connection){
2671         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2672     }
2673     uint8_t status = hfp_ag_setup_audio_connection(hfp_connection);
2674     if (status != ERROR_CODE_SUCCESS){
2675         return status;
2676     }
2677     hfp_ag_run_for_context(hfp_connection);
2678     return ERROR_CODE_SUCCESS;
2679 }
2680 
2681 uint8_t hfp_ag_release_audio_connection(hci_con_handle_t acl_handle){
2682     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2683     if (!hfp_connection){
2684         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2685     }
2686 
2687     if (hfp_connection->vra_state == HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
2688         return ERROR_CODE_COMMAND_DISALLOWED;
2689     }
2690 
2691     uint8_t status = hfp_trigger_release_audio_connection(hfp_connection);
2692     if (status == ERROR_CODE_SUCCESS){
2693         hfp_ag_run_for_context(hfp_connection);
2694     }
2695     return status;
2696 }
2697 
2698 /**
2699  * @brief Enable in-band ring tone
2700  */
2701 void hfp_ag_set_use_in_band_ring_tone(int use_in_band_ring_tone){
2702     if (get_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE) == use_in_band_ring_tone){
2703         return;
2704     }
2705 
2706     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE, use_in_band_ring_tone);
2707 
2708     btstack_linked_list_iterator_t it;
2709     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2710     while (btstack_linked_list_iterator_has_next(&it)){
2711         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2712         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2713         hfp_connection->ag_send_in_band_ring_tone_setting = true;
2714         hfp_ag_run_for_context(hfp_connection);
2715     }
2716 }
2717 
2718 /**
2719  * @brief Called from GSM
2720  */
2721 void hfp_ag_incoming_call(void){
2722     hfp_ag_call_sm(HFP_AG_INCOMING_CALL, NULL);
2723 }
2724 
2725 void hfp_ag_outgoing_call_initiated(const char * number) {
2726     UNUSED(number);
2727     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, NULL);
2728 }
2729 
2730 /**
2731  * @brief number is stored.
2732  */
2733 void hfp_ag_set_clip(uint8_t type, const char * number){
2734     hfp_gsm_handler(HFP_AG_SET_CLIP, 0, type, number);
2735 }
2736 
2737 void hfp_ag_call_dropped(void){
2738     hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2739 }
2740 
2741 // call from AG UI
2742 void hfp_ag_answer_incoming_call(void){
2743     hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, NULL);
2744 }
2745 
2746 void hfp_ag_join_held_call(void){
2747     hfp_ag_call_sm(HFP_AG_HELD_CALL_JOINED_BY_AG, NULL);
2748 }
2749 
2750 void hfp_ag_terminate_call(void){
2751     hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_AG, NULL);
2752 }
2753 
2754 void hfp_ag_outgoing_call_ringing(void){
2755     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_RINGING, NULL);
2756 }
2757 
2758 void hfp_ag_outgoing_call_established(void){
2759     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ESTABLISHED, NULL);
2760 }
2761 
2762 void hfp_ag_outgoing_call_rejected(void){
2763     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_REJECTED, NULL);
2764 }
2765 
2766 void hfp_ag_outgoing_call_accepted(void){
2767     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ACCEPTED, NULL);
2768 }
2769 
2770 void hfp_ag_hold_incoming_call(void){
2771     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, NULL);
2772 }
2773 
2774 void hfp_ag_accept_held_incoming_call(void) {
2775     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, NULL);
2776 }
2777 
2778 void hfp_ag_reject_held_incoming_call(void){
2779     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, NULL);
2780 }
2781 
2782 static void hfp_ag_set_ag_indicator(const char * name, int value){
2783     int indicator_index = get_ag_indicator_index_for_name(name);
2784     if (indicator_index < 0) return;
2785     hfp_ag_indicators[indicator_index].status = value;
2786 
2787     btstack_linked_list_iterator_t it;
2788     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2789     while (btstack_linked_list_iterator_has_next(&it)){
2790         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2791         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2792         if (!hfp_connection->ag_indicators[indicator_index].enabled) {
2793             log_info("Requested AG indicator '%s' update to %u, but it is not enabled", hfp_ag_indicators[indicator_index].name, value);
2794             continue;
2795         }
2796         log_info("AG indicator '%s' changed to %u, request transfer status", hfp_ag_indicators[indicator_index].name, value);
2797         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
2798         hfp_ag_run_for_context(hfp_connection);
2799     }
2800 }
2801 
2802 uint8_t hfp_ag_set_registration_status(int registration_status){
2803     if ((registration_status < 0) || (registration_status > 1)){
2804         return ERROR_CODE_COMMAND_DISALLOWED;
2805     }
2806 
2807     if ( (registration_status == 0) && (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT)){
2808 
2809         // if network goes away wihle a call is active:
2810         // - the  call gets dropped
2811         // - we send NO CARRIER
2812         // NOTE: the CALL=0 has to be sent before NO CARRIER
2813 
2814         hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2815 
2816         btstack_linked_list_iterator_t it;
2817         btstack_linked_list_iterator_init(&it, hfp_get_connections());
2818         while (btstack_linked_list_iterator_has_next(&it)){
2819             hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2820             hfp_connection->ag_send_no_carrier = true;
2821         }
2822     }
2823     hfp_ag_set_ag_indicator("service", registration_status);
2824     return ERROR_CODE_SUCCESS;
2825 }
2826 
2827 uint8_t hfp_ag_set_signal_strength(int signal_strength){
2828     if ((signal_strength < 0) || (signal_strength > 5)){
2829         return ERROR_CODE_COMMAND_DISALLOWED;
2830     }
2831 
2832     hfp_ag_set_ag_indicator("signal", signal_strength);
2833     return ERROR_CODE_SUCCESS;
2834 }
2835 
2836 uint8_t hfp_ag_set_roaming_status(int roaming_status){
2837     if ((roaming_status < 0) || (roaming_status > 1)){
2838         return ERROR_CODE_COMMAND_DISALLOWED;
2839     }
2840 
2841     hfp_ag_set_ag_indicator("roam", roaming_status);
2842     return ERROR_CODE_SUCCESS;
2843 }
2844 
2845 uint8_t hfp_ag_set_battery_level(int battery_level){
2846     if ((battery_level < 0) || (battery_level > 5)){
2847         return ERROR_CODE_COMMAND_DISALLOWED;
2848     }
2849     hfp_ag_set_ag_indicator("battchg", battery_level);
2850     return ERROR_CODE_SUCCESS;
2851 }
2852 
2853 uint8_t hfp_ag_activate_voice_recognition(hci_con_handle_t acl_handle){
2854     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2855     if (!hfp_connection){
2856         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2857     }
2858 
2859     if (hfp_connection->emit_vra_enabled_after_audio_established){
2860         return ERROR_CODE_COMMAND_DISALLOWED;
2861     }
2862 
2863     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2864     bool legacy_vra_supported   = hfp_ag_vra_flag_supported(hfp_connection);
2865     if (!enhanced_vra_supported && !legacy_vra_supported){
2866         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2867     }
2868 
2869     if (!hfp_ag_can_activate_voice_recognition(hfp_connection)){
2870         return ERROR_CODE_COMMAND_DISALLOWED;
2871     }
2872 
2873     hfp_connection->ag_activate_voice_recognition_value = 1;
2874     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
2875     hfp_connection->enhanced_voice_recognition_enabled = enhanced_vra_supported;
2876     hfp_connection->ag_audio_connection_opened_before_vra = hfp_ag_is_audio_connection_active(hfp_connection);
2877     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2878     hfp_connection->ag_vra_send_command = true;
2879     hfp_ag_run_for_context(hfp_connection);
2880     return ERROR_CODE_SUCCESS;
2881 }
2882 
2883 uint8_t hfp_ag_deactivate_voice_recognition(hci_con_handle_t acl_handle){
2884     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2885     if (!hfp_connection){
2886         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2887     }
2888 
2889     if (hfp_connection->emit_vra_enabled_after_audio_established){
2890         return ERROR_CODE_COMMAND_DISALLOWED;
2891     }
2892 
2893     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2894     bool legacy_vra_supported = hfp_ag_vra_flag_supported(hfp_connection);
2895 
2896     if (!enhanced_vra_supported && !legacy_vra_supported){
2897         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2898     }
2899 
2900     if (!hfp_ag_voice_recognition_session_active(hfp_connection)){
2901         return ERROR_CODE_COMMAND_DISALLOWED;
2902     }
2903 
2904     hfp_connection->ag_activate_voice_recognition_value = 0;
2905     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
2906     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2907     hfp_connection->ag_vra_send_command = true;
2908     hfp_ag_run_for_context(hfp_connection);
2909     return ERROR_CODE_SUCCESS;
2910 }
2911 
2912 static uint8_t hfp_ag_enhanced_voice_recognition_send_state(hci_con_handle_t acl_handle, hfp_voice_recognition_state_t state){
2913     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2914     if (!hfp_connection){
2915         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2916     }
2917 
2918     if (hfp_connection->emit_vra_enabled_after_audio_established){
2919         return ERROR_CODE_COMMAND_DISALLOWED;
2920     }
2921 
2922     if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED){
2923         return ERROR_CODE_COMMAND_DISALLOWED;
2924     }
2925 
2926     if (hfp_connection->vra_state != HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
2927         return ERROR_CODE_COMMAND_DISALLOWED;
2928     }
2929 
2930     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2931     if (!enhanced_vra_supported ){
2932         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2933     }
2934 
2935 
2936     hfp_connection->ag_vra_state = state;
2937     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS;
2938     hfp_connection->ag_vra_send_command = true;
2939     hfp_ag_run_for_context(hfp_connection);
2940     return ERROR_CODE_SUCCESS;
2941 }
2942 
2943 uint8_t hfp_ag_enhanced_voice_recognition_report_sending_audio(hci_con_handle_t acl_handle){
2944     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_STARTING_SOUND);
2945 }
2946 uint8_t hfp_ag_enhanced_voice_recognition_report_ready_for_audio(hci_con_handle_t acl_handle){
2947     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_READY_TO_ACCEPT_AUDIO_INPUT);
2948 }
2949 uint8_t hfp_ag_enhanced_voice_recognition_report_processing_input(hci_con_handle_t acl_handle){
2950     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_PROCESSING_AUDIO_INPUT);
2951 }
2952 
2953 
2954 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){
2955     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2956     if (!hfp_connection){
2957         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2958     }
2959 
2960     if (hfp_connection->emit_vra_enabled_after_audio_established){
2961         return ERROR_CODE_COMMAND_DISALLOWED;
2962     }
2963 
2964     if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED){
2965         return ERROR_CODE_COMMAND_DISALLOWED;
2966     }
2967 
2968     if (hfp_connection->vra_state != HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
2969         return ERROR_CODE_COMMAND_DISALLOWED;
2970     }
2971 
2972     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2973     if (!enhanced_vra_supported ){
2974         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2975     }
2976 
2977     bool enhanced_vra_msg_supported = hfp_ag_can_send_enhanced_vra_message_flag_supported(hfp_connection);
2978     if (!enhanced_vra_msg_supported ){
2979         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2980     }
2981 
2982     uint16_t message_len = strlen(msg.text);
2983 
2984     if (message_len > HFP_MAX_VR_TEXT_SIZE){
2985         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2986     }
2987 
2988     if ((HFP_VR_TEXT_HEADER_SIZE + message_len) > hfp_connection->rfcomm_mtu){
2989         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2990     }
2991 
2992     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG;
2993     hfp_connection->ag_msg = msg;
2994     hfp_connection->ag_vra_state = state;
2995     hfp_connection->ag_vra_send_command = true;
2996     hfp_ag_run_for_context(hfp_connection);
2997 
2998     return ERROR_CODE_SUCCESS;
2999 }
3000 
3001 
3002 uint8_t hfp_ag_set_microphone_gain(hci_con_handle_t acl_handle, int gain){
3003     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3004     if (!hfp_connection){
3005         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3006     }
3007 
3008     if ((gain < 0) || (gain > 15)){
3009         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
3010         return ERROR_CODE_COMMAND_DISALLOWED;
3011     }
3012 
3013     if (hfp_connection->microphone_gain != gain){
3014         hfp_connection->microphone_gain = gain;
3015         hfp_connection->send_microphone_gain = 1;
3016     }
3017     hfp_ag_run_for_context(hfp_connection);
3018     return ERROR_CODE_SUCCESS;
3019 }
3020 
3021 uint8_t hfp_ag_set_speaker_gain(hci_con_handle_t acl_handle, int gain){
3022     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3023     if (!hfp_connection){
3024         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3025     }
3026 
3027     if ((gain < 0) || (gain > 15)){
3028         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
3029         return ERROR_CODE_COMMAND_DISALLOWED;
3030     }
3031 
3032     if (hfp_connection->speaker_gain != gain){
3033         hfp_connection->speaker_gain = gain;
3034         hfp_connection->send_speaker_gain = 1;
3035     }
3036     hfp_ag_run_for_context(hfp_connection);
3037     return ERROR_CODE_SUCCESS;
3038 }
3039 
3040 uint8_t hfp_ag_send_phone_number_for_voice_tag(hci_con_handle_t acl_handle, const char * number){
3041     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3042     if (!hfp_connection){
3043         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3044     }
3045 
3046     hfp_ag_set_clip(0, number);
3047     hfp_connection->send_phone_number_for_voice_tag = 1;
3048     return ERROR_CODE_SUCCESS;
3049 }
3050 
3051 uint8_t hfp_ag_reject_phone_number_for_voice_tag(hci_con_handle_t acl_handle){
3052     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3053     if (!hfp_connection){
3054         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3055     }
3056 
3057     hfp_connection->send_error = 1;
3058     return ERROR_CODE_SUCCESS;
3059 }
3060 
3061 uint8_t hfp_ag_send_dtmf_code_done(hci_con_handle_t acl_handle){
3062     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3063     if (!hfp_connection){
3064         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3065     }
3066 
3067     hfp_connection->ok_pending = 1;
3068     return ERROR_CODE_SUCCESS;
3069 }
3070 
3071 void hfp_ag_set_subcriber_number_information(hfp_phone_number_t * numbers, int numbers_count){
3072     hfp_ag_subscriber_numbers = numbers;
3073     hfp_ag_subscriber_numbers_count = numbers_count;
3074 }
3075 
3076 void hfp_ag_clear_last_dialed_number(void){
3077     hfp_gsm_clear_last_dialed_number();
3078 }
3079 
3080 void hfp_ag_set_last_dialed_number(const char * number){
3081     hfp_gsm_set_last_dialed_number(number);
3082 }
3083 
3084 uint8_t hfp_ag_notify_incoming_call_waiting(hci_con_handle_t acl_handle){
3085     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3086     if (!hfp_connection){
3087         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3088     }
3089 
3090     if (!hfp_connection->call_waiting_notification_enabled){
3091         return ERROR_CODE_COMMAND_DISALLOWED;
3092     }
3093 
3094     hfp_connection->ag_notify_incoming_call_waiting = 1;
3095     hfp_ag_run_for_context(hfp_connection);
3096     return ERROR_CODE_SUCCESS;
3097 }
3098 
3099 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){
3100 	if (!name){
3101 		name = hfp_ag_default_service_name;
3102 	}
3103 	hfp_create_sdp_record(service, service_record_handle, BLUETOOTH_SERVICE_CLASS_HANDSFREE_AUDIO_GATEWAY, rfcomm_channel_nr, name);
3104 
3105 	/*
3106 	 * 0x01 – Ability to reject a call
3107 	 * 0x00 – No ability to reject a call
3108 	 */
3109 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0301);    // Hands-Free Profile - Network
3110 	de_add_number(service, DE_UINT, DE_SIZE_8, ability_to_reject_call);
3111 
3112 	// Construct SupportedFeatures for SDP bitmap:
3113 	//
3114 	// "The values of the “SupportedFeatures” bitmap given in Table 5.4 shall be the same as the values
3115 	//  of the Bits 0 to 4 of the unsolicited result code +BRSF"
3116 	//
3117 	// Wide band speech (bit 5) requires Codec negotiation
3118 	//
3119 	uint16_t sdp_features = supported_features & 0x1f;
3120 	if ( (wide_band_speech == 1) && (supported_features & (1 << HFP_AGSF_CODEC_NEGOTIATION))){
3121 		sdp_features |= 1 << 5;
3122 	}
3123 
3124     if (supported_features & (1 << HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS)){
3125         sdp_features |= 1 << 6;
3126     }
3127 
3128     if (supported_features & (1 << HFP_AGSF_VOICE_RECOGNITION_TEXT)){
3129         sdp_features |= 1 << 7;
3130     }
3131 
3132 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);    // Hands-Free Profile - SupportedFeatures
3133 	de_add_number(service, DE_UINT, DE_SIZE_16, sdp_features);
3134 }
3135 
3136 void hfp_ag_register_packet_handler(btstack_packet_handler_t callback){
3137 	btstack_assert(callback != NULL);
3138 
3139 	hfp_ag_callback = callback;
3140 	hfp_set_ag_callback(callback);
3141 }
3142