xref: /btstack/src/classic/hfp_ag.c (revision 884d3c56f3c839726594fcf182a0e2d13048dadf)
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_W4_AUDIO_CONNECTION_FOR_IN_BAND_RING:
1175             case HFP_CALL_OUTGOING_RINGING:
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 
1465             // we got event: audio hfp_connection established
1466             hfp_connection->call_state = HFP_CALL_INCOMING_RINGING;
1467             break;
1468         case HFP_CALL_W4_AUDIO_CONNECTION_FOR_ACTIVE:
1469             if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED) return 0;
1470             // we got event: audio hfp_connection established
1471             hfp_connection->call_state = HFP_CALL_ACTIVE;
1472             break;
1473         case HFP_CALL_W2_SEND_CALL_WAITING:
1474             hfp_connection->call_state = HFP_CALL_W4_CHLD;
1475             hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
1476             indicator_index = get_ag_indicator_index_for_name("callsetup");
1477             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
1478             break;
1479         default:
1480             break;
1481     }
1482     return 0;
1483 }
1484 
1485 // functions extracted from hfp_ag_call_sm below
1486 static void hfp_ag_handle_reject_outgoing_call(void){
1487     hfp_connection_t * hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1488     if (!hfp_connection){
1489         log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1490         return;
1491     }
1492 
1493     hfp_gsm_handler(HFP_AG_OUTGOING_CALL_REJECTED, 0, 0, NULL);
1494     hfp_connection->call_state = HFP_CALL_IDLE;
1495     hfp_connection->send_error = 1;
1496     hfp_ag_run_for_context(hfp_connection);
1497 }
1498 
1499 // hfp_connection is used to identify originating HF
1500 static void hfp_ag_call_sm(hfp_ag_call_event_t event, hfp_connection_t * hfp_connection){
1501     int callsetup_indicator_index = get_ag_indicator_index_for_name("callsetup");
1502     int callheld_indicator_index = get_ag_indicator_index_for_name("callheld");
1503     int call_indicator_index = get_ag_indicator_index_for_name("call");
1504 
1505     switch (event){
1506         case HFP_AG_INCOMING_CALL:
1507             switch (hfp_gsm_call_status()){
1508                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1509                     switch (hfp_gsm_callsetup_status()){
1510                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1511                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1512                             hfp_ag_set_callsetup_indicator();
1513                             hfp_ag_trigger_incoming_call_idle();
1514                             log_info("AG rings");
1515                             break;
1516                         default:
1517                             break;
1518                     }
1519                     break;
1520                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1521                     switch (hfp_gsm_callsetup_status()){
1522                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1523                             hfp_gsm_handler(HFP_AG_INCOMING_CALL, 0, 0, NULL);
1524                             hfp_ag_set_callsetup_indicator();
1525                             hfp_ag_trigger_incoming_call_during_active_one();
1526                             log_info("AG call waiting");
1527                             break;
1528                         default:
1529                             break;
1530                     }
1531                     break;
1532                 default:
1533                     break;
1534             }
1535             break;
1536         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG:
1537             switch (hfp_gsm_call_status()){
1538                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1539                     switch (hfp_gsm_callsetup_status()){
1540                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1541                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1542                             hfp_ag_set_call_indicator();
1543                             hfp_ag_set_callsetup_indicator();
1544                             hfp_ag_ag_accept_call();
1545                             log_info("AG answers call, accept call by GSM");
1546                             break;
1547                         default:
1548                             break;
1549                     }
1550                     break;
1551                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1552                     switch (hfp_gsm_callsetup_status()){
1553                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1554                             log_info("AG: current call is placed on hold, incoming call gets active");
1555                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, 0, 0, NULL);
1556                             hfp_ag_set_callsetup_indicator();
1557                             hfp_ag_set_callheld_indicator();
1558                             hfp_ag_transfer_callsetup_state();
1559                             hfp_ag_transfer_callheld_state();
1560                             break;
1561                         default:
1562                             break;
1563                     }
1564                     break;
1565                 default:
1566                     break;
1567             }
1568             break;
1569 
1570         case HFP_AG_HELD_CALL_JOINED_BY_AG:
1571             switch (hfp_gsm_call_status()){
1572                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1573                     switch (hfp_gsm_callheld_status()){
1574                         case HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED:
1575                             log_info("AG: joining held call with active call");
1576                             hfp_gsm_handler(HFP_AG_HELD_CALL_JOINED_BY_AG, 0, 0, NULL);
1577                             hfp_ag_set_callheld_indicator();
1578                             hfp_ag_transfer_callheld_state();
1579                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1580                             break;
1581                         default:
1582                             break;
1583                     }
1584                     break;
1585                 default:
1586                     break;
1587             }
1588             break;
1589 
1590         case HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF:
1591             switch (hfp_gsm_call_status()){
1592                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1593                     switch (hfp_gsm_callsetup_status()){
1594                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1595                             hfp_gsm_handler(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, 0, 0, NULL);
1596                             hfp_ag_set_callsetup_indicator();
1597                             hfp_ag_set_call_indicator();
1598                             hfp_ag_hf_accept_call(hfp_connection);
1599                             hfp_connection->ok_pending = 1;
1600                             log_info("HF answers call, accept call by GSM");
1601                             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1602                             break;
1603                         default:
1604                             break;
1605                     }
1606                     break;
1607                 default:
1608                     break;
1609             }
1610             break;
1611 
1612         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG:
1613             switch (hfp_gsm_call_status()){
1614                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1615                     switch (hfp_gsm_callsetup_status()){
1616                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1617                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, 0, 0, NULL);
1618                             hfp_ag_response_and_hold_active = true;
1619                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1620                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1621                             // as with regular call
1622                             hfp_ag_set_call_indicator();
1623                             hfp_ag_set_callsetup_indicator();
1624                             hfp_ag_ag_accept_call();
1625                             log_info("AG response and hold - hold by AG");
1626                             break;
1627                         default:
1628                             break;
1629                     }
1630                     break;
1631                 default:
1632                     break;
1633             }
1634             break;
1635 
1636         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF:
1637             switch (hfp_gsm_call_status()){
1638                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1639                     switch (hfp_gsm_callsetup_status()){
1640                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1641                             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, 0, 0, NULL);
1642                             hfp_ag_response_and_hold_active = true;
1643                             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
1644                             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1645                             // as with regular call
1646                             hfp_ag_set_call_indicator();
1647                             hfp_ag_set_callsetup_indicator();
1648                             hfp_ag_hf_accept_call(hfp_connection);
1649                             log_info("AG response and hold - hold by HF");
1650                             break;
1651                         default:
1652                             break;
1653                     }
1654                     break;
1655                 default:
1656                     break;
1657             }
1658             break;
1659 
1660         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG:
1661         case HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF:
1662             if (!hfp_ag_response_and_hold_active) break;
1663             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1664             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, 0, 0, NULL);
1665             hfp_ag_response_and_hold_active = false;
1666             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED;
1667             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1668             log_info("Held Call accepted and active");
1669             break;
1670 
1671         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG:
1672         case HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF:
1673             if (!hfp_ag_response_and_hold_active) break;
1674             if (hfp_ag_response_and_hold_state != HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD) break;
1675             hfp_gsm_handler(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, 0, 0, NULL);
1676             hfp_ag_response_and_hold_active = false;
1677             hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1678             hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1679             // from terminate by ag
1680             hfp_ag_set_call_indicator();
1681             hfp_ag_trigger_terminate_call();
1682             break;
1683 
1684         case HFP_AG_TERMINATE_CALL_BY_HF:
1685             switch (hfp_gsm_call_status()){
1686                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1687                     switch (hfp_gsm_callsetup_status()){
1688                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1689                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1690                             hfp_ag_set_callsetup_indicator();
1691                             hfp_ag_transfer_callsetup_state();
1692                             hfp_ag_trigger_reject_call();
1693                             log_info("HF Rejected Incoming call, AG terminate call");
1694                             break;
1695                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1696                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1697                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1698                             hfp_ag_set_callsetup_indicator();
1699                             hfp_ag_transfer_callsetup_state();
1700                             log_info("AG terminate outgoing call process");
1701                             break;
1702                         default:
1703                             break;
1704                     }
1705                     break;
1706                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1707                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_HF, 0, 0, NULL);
1708                     hfp_ag_set_callsetup_indicator();
1709                     hfp_ag_set_call_indicator();
1710                     hfp_ag_trigger_terminate_call();
1711                     log_info("AG terminate call");
1712                     break;
1713                 default:
1714                     break;
1715             }
1716             break;
1717 
1718         case HFP_AG_TERMINATE_CALL_BY_AG:
1719             switch (hfp_gsm_call_status()){
1720                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1721                     switch (hfp_gsm_callsetup_status()){
1722                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1723                             hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1724                             hfp_ag_set_callsetup_indicator();
1725                             hfp_ag_trigger_reject_call();
1726                             log_info("AG Rejected Incoming call, AG terminate call");
1727                             break;
1728                         default:
1729                             break;
1730                     }
1731                     break;
1732                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1733                     hfp_gsm_handler(HFP_AG_TERMINATE_CALL_BY_AG, 0, 0, NULL);
1734                     hfp_ag_set_callsetup_indicator();
1735                     hfp_ag_set_call_indicator();
1736                     hfp_ag_trigger_terminate_call();
1737                     log_info("AG terminate call");
1738                     break;
1739                 default:
1740                     break;
1741             }
1742             break;
1743         case HFP_AG_CALL_DROPPED:
1744             switch (hfp_gsm_call_status()){
1745                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1746                     switch (hfp_gsm_callsetup_status()){
1747                         case HFP_CALLSETUP_STATUS_INCOMING_CALL_SETUP_IN_PROGRESS:
1748                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_ALERTING_STATE:
1749                             hfp_ag_stop_ringing();
1750                             break;
1751                         case HFP_CALLSETUP_STATUS_OUTGOING_CALL_SETUP_IN_DIALING_STATE:
1752                             log_info("Outgoing call interrupted\n");
1753                             break;
1754                         default:
1755                             break;
1756                     }
1757                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1758                     hfp_ag_set_callsetup_indicator();
1759                     hfp_ag_transfer_callsetup_state();
1760                     hfp_ag_trigger_terminate_call();
1761                     break;
1762                 case HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT:
1763                     if (hfp_ag_response_and_hold_active) {
1764                         hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1765                         hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED;
1766                         hfp_ag_send_response_and_hold_state(hfp_ag_response_and_hold_state);
1767                     }
1768                     hfp_gsm_handler(HFP_AG_CALL_DROPPED, 0, 0, NULL);
1769                     hfp_ag_set_callsetup_indicator();
1770                     hfp_ag_set_call_indicator();
1771                     hfp_ag_trigger_terminate_call();
1772                     log_info("AG notify call dropped");
1773                     break;
1774                 default:
1775                     break;
1776             }
1777             break;
1778 
1779         case HFP_AG_OUTGOING_CALL_INITIATED_BY_HF:
1780             // directly reject call if number of free slots is exceeded
1781             if (!hfp_gsm_call_possible()){
1782                 hfp_connection->send_error = 1;
1783                 hfp_ag_run_for_context(hfp_connection);
1784                 break;
1785             }
1786 
1787             // note: number not used currently
1788             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, 0, 0, (const char *) &hfp_connection->line_buffer[3]);
1789 
1790             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1791 
1792             hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, (const char *) &hfp_connection->line_buffer[3]);
1793             break;
1794 
1795         case HFP_AG_OUTGOING_CALL_INITIATED_BY_AG:
1796             // directly reject call if number of free slots is exceeded
1797             if (!hfp_gsm_call_possible()) {
1798                 // TODO: no error for user
1799                 break;
1800             }
1801             switch (hfp_gsm_call_status()) {
1802                 case HFP_CALL_STATUS_NO_HELD_OR_ACTIVE_CALLS:
1803                     switch (hfp_gsm_callsetup_status()) {
1804                         case HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS:
1805                             // note: number not used currently
1806                             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, 0, 0, "1234567");
1807                             // init call state for all connections
1808                             hfp_ag_trigger_outgoing_call();
1809                             // get first one and accept call
1810                             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1811                             if (hfp_connection) {
1812                                 hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1813                             }
1814                             break;
1815                         default:
1816                             // TODO: no error for user
1817                             break;
1818                     }
1819                     break;
1820                 default:
1821                     // TODO: no error for user
1822                     break;
1823             }
1824             break;
1825         case HFP_AG_OUTGOING_REDIAL_INITIATED:{
1826             // directly reject call if number of free slots is exceeded
1827             if (!hfp_gsm_call_possible()){
1828                 hfp_connection->send_error = 1;
1829                 hfp_ag_run_for_context(hfp_connection);
1830                 break;
1831             }
1832 
1833             hfp_gsm_handler(HFP_AG_OUTGOING_REDIAL_INITIATED, 0, 0, NULL);
1834             hfp_connection->call_state = HFP_CALL_OUTGOING_INITIATED;
1835 
1836             log_info("Redial last number");
1837             char * last_dialed_number = hfp_gsm_last_dialed_number();
1838 
1839             if (strlen(last_dialed_number) > 0){
1840                 log_info("Last number exists: accept call");
1841                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_PLACE_CALL_WITH_NUMBER, last_dialed_number);
1842             } else {
1843                 log_info("log_infoLast number missing: reject call");
1844                 hfp_ag_handle_reject_outgoing_call();
1845             }
1846             break;
1847         }
1848         case HFP_AG_OUTGOING_CALL_REJECTED:
1849             hfp_ag_handle_reject_outgoing_call();
1850             break;
1851 
1852         case HFP_AG_OUTGOING_CALL_ACCEPTED:{
1853             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_INITIATED);
1854             if (!hfp_connection){
1855                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in initiated state");
1856                 break;
1857             }
1858 
1859             hfp_connection->ok_pending = 1;
1860             hfp_ag_handle_outgoing_call_accepted(hfp_connection);
1861             break;
1862         }
1863         case HFP_AG_OUTGOING_CALL_RINGING:
1864             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1865             if (!hfp_connection){
1866                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection in dialing state");
1867                 break;
1868             }
1869 
1870             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_RINGING, 0, 0, NULL);
1871             hfp_connection->call_state = HFP_CALL_OUTGOING_RINGING;
1872             hfp_ag_set_callsetup_indicator();
1873             hfp_ag_transfer_callsetup_state();
1874             hfp_ag_hf_start_ringing_outgoing(hfp_connection);
1875             break;
1876 
1877         case HFP_AG_OUTGOING_CALL_ESTABLISHED:{
1878             // get outgoing call
1879             hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_RINGING);
1880             if (!hfp_connection){
1881                 hfp_connection = hfp_ag_connection_for_call_state(HFP_CALL_OUTGOING_DIALING);
1882             }
1883             if (!hfp_connection){
1884                 log_info("hfp_ag_call_sm: did not find outgoing hfp_connection");
1885                 break;
1886             }
1887 
1888             bool callheld_status_call_on_hold_and_no_active_calls = hfp_gsm_callheld_status() == HFP_CALLHELD_STATUS_CALL_ON_HOLD_AND_NO_ACTIVE_CALLS;
1889             hfp_gsm_handler(HFP_AG_OUTGOING_CALL_ESTABLISHED, 0, 0, NULL);
1890             hfp_connection->call_state = HFP_CALL_ACTIVE;
1891             hfp_ag_set_callsetup_indicator();
1892             hfp_ag_set_call_indicator();
1893             hfp_ag_transfer_call_state();
1894             hfp_ag_transfer_callsetup_state();
1895             if (callheld_status_call_on_hold_and_no_active_calls){
1896                 hfp_ag_set_callheld_indicator();
1897                 hfp_ag_transfer_callheld_state();
1898             }
1899             hfp_ag_hf_stop_ringing(hfp_connection);
1900             hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CALL_ANSWERED);
1901             break;
1902         }
1903 
1904         case HFP_AG_CALL_HOLD_USER_BUSY:
1905             hfp_gsm_handler(HFP_AG_CALL_HOLD_USER_BUSY, 0, 0, NULL);
1906             hfp_ag_set_callsetup_indicator();
1907             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1908             hfp_connection->call_state = HFP_CALL_ACTIVE;
1909             log_info("AG: Call Waiting, User Busy");
1910             break;
1911 
1912         case HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1913             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1914             int call_held = hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD;
1915 
1916             // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
1917             if (call_held || call_setup_in_progress){
1918                 hfp_gsm_handler(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index,
1919                                 0, NULL);
1920 
1921             }
1922 
1923             if (call_setup_in_progress){
1924                 log_info("AG: Call Dropped, Accept new call");
1925                 hfp_ag_set_callsetup_indicator();
1926                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1927             } else {
1928                 log_info("AG: Call Dropped, Resume held call");
1929             }
1930             if (call_held){
1931                 hfp_ag_set_callheld_indicator();
1932                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1933             }
1934 
1935             hfp_connection->call_state = HFP_CALL_ACTIVE;
1936             break;
1937         }
1938 
1939         case HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL:{
1940             // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
1941             // only update if callsetup changed
1942             int call_setup_in_progress = hfp_gsm_callsetup_status() != HFP_CALLSETUP_STATUS_NO_CALL_SETUP_IN_PROGRESS;
1943             hfp_gsm_handler(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection->call_index, 0,
1944                             NULL);
1945 
1946             if (call_setup_in_progress){
1947                 log_info("AG: Call on Hold, Accept new call");
1948                 hfp_ag_set_callsetup_indicator();
1949                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callsetup_indicator_index, 1);
1950             } else {
1951                 log_info("AG: Swap calls");
1952             }
1953 
1954             hfp_ag_set_callheld_indicator();
1955             // hfp_ag_set_callheld_state(HFP_CALLHELD_STATUS_CALL_ON_HOLD_OR_SWAPPED);
1956             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1957             hfp_connection->call_state = HFP_CALL_ACTIVE;
1958             break;
1959         }
1960 
1961         case HFP_AG_CALL_HOLD_ADD_HELD_CALL:
1962             // Adds a held call to the conversation.
1963             if (hfp_gsm_callheld_status() != HFP_CALLHELD_STATUS_NO_CALLS_HELD){
1964                 log_info("AG: Join 3-way-call");
1965                 hfp_gsm_handler(HFP_AG_CALL_HOLD_ADD_HELD_CALL, 0, 0, NULL);
1966                 hfp_ag_set_callheld_indicator();
1967                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1968                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_CONFERENCE_CALL);
1969             }
1970             hfp_connection->call_state = HFP_CALL_ACTIVE;
1971             break;
1972         case HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS:
1973             // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer)
1974             hfp_gsm_handler(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, 0, 0, NULL);
1975             log_info("AG: Transfer call -> Connect two calls and disconnect");
1976             hfp_ag_set_call_indicator();
1977             hfp_ag_set_callheld_indicator();
1978             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, call_indicator_index, 1);
1979             hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, callheld_indicator_index, 1);
1980             hfp_connection->call_state = HFP_CALL_IDLE;
1981             break;
1982 
1983         default:
1984             break;
1985     }
1986 
1987 
1988 }
1989 
1990 
1991 static void hfp_ag_send_call_status(hfp_connection_t * hfp_connection, int call_index){
1992     hfp_gsm_call_t * active_call = hfp_gsm_call(call_index);
1993     if (!active_call) return;
1994 
1995     int idx = active_call->index;
1996     hfp_enhanced_call_dir_t dir = active_call->direction;
1997     hfp_enhanced_call_status_t status = active_call->enhanced_status;
1998     hfp_enhanced_call_mode_t mode = active_call->mode;
1999     hfp_enhanced_call_mpty_t mpty = active_call->mpty;
2000     uint8_t type = active_call->clip_type;
2001     char * number = active_call->clip_number;
2002 
2003     char buffer[100];
2004     // TODO: check length of a buffer, to fit the MTU
2005     int offset = snprintf(buffer, sizeof(buffer), "\r\n%s: %d,%d,%d,%d,%d", HFP_LIST_CURRENT_CALLS, idx, dir, status, mode, mpty);
2006     if (number){
2007         offset += snprintf(buffer+offset, sizeof(buffer)-offset-3, ", \"%s\",%u", number, type);
2008     }
2009     snprintf(buffer+offset, sizeof(buffer)-offset, "\r\n");
2010     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,
2011        mode, mpty, type, number);
2012     send_str_over_rfcomm(hfp_connection->rfcomm_cid, buffer);
2013 }
2014 
2015 // sends pending command, returns if command was sent
2016 static int hfp_ag_send_commands(hfp_connection_t *hfp_connection){
2017     if (hfp_connection->send_status_of_current_calls){
2018         hfp_connection->ok_pending = 0;
2019         if (hfp_connection->next_call_index < hfp_gsm_get_number_of_calls()){
2020             hfp_connection->next_call_index++;
2021             hfp_ag_send_call_status(hfp_connection, hfp_connection->next_call_index);
2022             return 1;
2023         } else {
2024             // 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
2025             hfp_connection->next_call_index = 0;
2026             hfp_connection->ok_pending = 1;
2027             hfp_connection->send_status_of_current_calls = 0;
2028         }
2029     }
2030 
2031     if (hfp_connection->ag_notify_incoming_call_waiting){
2032         hfp_connection->ag_notify_incoming_call_waiting = 0;
2033         hfp_ag_send_call_waiting_notification(hfp_connection->rfcomm_cid);
2034         return 1;
2035     }
2036 
2037     if (hfp_connection->send_error){
2038         hfp_connection->send_error = 0;
2039         hfp_connection->command = HFP_CMD_NONE;
2040         hfp_ag_send_error(hfp_connection->rfcomm_cid);
2041         return 1;
2042     }
2043 
2044     // note: before update AG indicators and ok_pending
2045     if (hfp_connection->send_response_and_hold_status){
2046         int status = hfp_connection->send_response_and_hold_status - 1;
2047         hfp_connection->send_response_and_hold_status = 0;
2048         hfp_ag_send_set_response_and_hold(hfp_connection->rfcomm_cid, status);
2049         return 1;
2050     }
2051 
2052     if (hfp_connection->ok_pending){
2053         hfp_connection->ok_pending = 0;
2054         hfp_connection->command = HFP_CMD_NONE;
2055         hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2056         return 1;
2057     }
2058 
2059     // update AG indicators
2060     if (hfp_connection->ag_indicators_status_update_bitmap){
2061         int i;
2062         for (i=0;i<hfp_connection->ag_indicators_nr;i++){
2063             if (get_bit(hfp_connection->ag_indicators_status_update_bitmap, i)){
2064                 hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, i, 0);
2065                 if (!hfp_connection->enable_status_update_for_ag_indicators) {
2066                     log_info("+CMER:3,0,0,0 - not sending update for '%s'", hfp_ag_indicators[i].name);
2067                     break;
2068                 }
2069                 hfp_ag_send_transfer_ag_indicators_status_cmd(hfp_connection->rfcomm_cid, &hfp_ag_indicators[i]);
2070                 return 1;
2071             }
2072         }
2073     }
2074 
2075     if (hfp_connection->ag_send_no_carrier){
2076         hfp_connection->ag_send_no_carrier = false;
2077         hfp_ag_send_no_carrier(hfp_connection->rfcomm_cid);
2078         return 1;
2079     }
2080 
2081     if (hfp_connection->ag_ring){
2082         hfp_connection->ag_ring = 0;
2083         hfp_connection->command = HFP_CMD_NONE;
2084         hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_RING);
2085         hfp_ag_send_ring(hfp_connection->rfcomm_cid);
2086         return 1;
2087     }
2088 
2089     if (hfp_connection->ag_send_clip){
2090         hfp_connection->ag_send_clip = 0;
2091         hfp_connection->command = HFP_CMD_NONE;
2092         hfp_ag_send_clip(hfp_connection->rfcomm_cid);
2093         return 1;
2094     }
2095 
2096     if (hfp_connection->send_phone_number_for_voice_tag){
2097         hfp_connection->send_phone_number_for_voice_tag = 0;
2098         hfp_connection->command = HFP_CMD_NONE;
2099         hfp_connection->ok_pending = 1;
2100         hfp_ag_send_phone_number_for_voice_tag_cmd(hfp_connection->rfcomm_cid);
2101         return 1;
2102     }
2103 
2104     if (hfp_connection->send_subscriber_number){
2105         if (hfp_connection->next_subscriber_number_to_send < hfp_ag_subscriber_numbers_count){
2106             hfp_phone_number_t phone = hfp_ag_subscriber_numbers[hfp_connection->next_subscriber_number_to_send++];
2107             hfp_send_subscriber_number_cmd(hfp_connection->rfcomm_cid, phone.type, phone.number);
2108         } else {
2109             hfp_connection->send_subscriber_number = 0;
2110             hfp_connection->next_subscriber_number_to_send = 0;
2111             hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2112         }
2113         hfp_connection->command = HFP_CMD_NONE;
2114         return 1;
2115     }
2116 
2117     if (hfp_connection->send_microphone_gain){
2118         hfp_connection->send_microphone_gain = 0;
2119         hfp_connection->command = HFP_CMD_NONE;
2120         hfp_ag_send_set_microphone_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->microphone_gain);
2121         return 1;
2122     }
2123 
2124     if (hfp_connection->send_speaker_gain){
2125         hfp_connection->send_speaker_gain = 0;
2126         hfp_connection->command = HFP_CMD_NONE;
2127         hfp_ag_send_set_speaker_gain_cmd(hfp_connection->rfcomm_cid, hfp_connection->speaker_gain);
2128         return 1;
2129     }
2130 
2131     if (hfp_connection->send_ag_status_indicators){
2132         hfp_connection->send_ag_status_indicators = 0;
2133         hfp_ag_send_retrieve_indicators_status_cmd(hfp_connection->rfcomm_cid);
2134         return 1;
2135     }
2136 
2137     return 0;
2138 }
2139 
2140 static void hfp_ag_run_for_context(hfp_connection_t *hfp_connection){
2141 
2142 	btstack_assert(hfp_connection != NULL);
2143 	btstack_assert(hfp_connection->local_role == HFP_ROLE_AG);
2144 
2145 	// during SDP query, RFCOMM CID is not set
2146 	if (hfp_connection->rfcomm_cid == 0) return;
2147 
2148     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED && hfp_connection->emit_vra_enabled_after_audio_established){
2149         hfp_connection->emit_vra_enabled_after_audio_established = false;
2150         hfp_emit_voice_recognition_enabled(hfp_connection, ERROR_CODE_SUCCESS);
2151     }
2152 
2153     // assert command could be sent
2154     if (hci_can_send_command_packet_now() == 0) return;
2155 
2156     if ((hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED) && hfp_connection->release_audio_connection){
2157         hfp_connection->state = HFP_W4_SCO_DISCONNECTED;
2158         hfp_connection->release_audio_connection = 0;
2159         gap_disconnect(hfp_connection->sco_handle);
2160         return;
2161     }
2162 
2163 #ifdef ENABLE_CC256X_ASSISTED_HFP
2164     // WBS Disassociate
2165     if (hfp_connection->cc256x_send_wbs_disassociate){
2166         hfp_connection->cc256x_send_wbs_disassociate = false;
2167         hci_send_cmd(&hci_ti_wbs_disassociate);
2168         return;
2169     }
2170     // Write Codec Config
2171     if (hfp_connection->cc256x_send_write_codec_config){
2172         hfp_connection->cc256x_send_write_codec_config = false;
2173         hfp_cc256x_write_codec_config(hfp_connection);
2174         return;
2175     }
2176     // WBS Associate
2177     if (hfp_connection->cc256x_send_wbs_associate){
2178         hfp_connection->cc256x_send_wbs_associate = false;
2179         hci_send_cmd(&hci_ti_wbs_associate, hfp_connection->acl_handle);
2180         return;
2181     }
2182 #endif
2183 #ifdef ENABLE_BCM_PCM_WBS
2184     // Enable WBS
2185     if (hfp_connection->bcm_send_enable_wbs){
2186         hfp_connection->bcm_send_enable_wbs = false;
2187         hci_send_cmd(&hci_bcm_enable_wbs, 1, 2);
2188         return;
2189     }
2190     // Write I2S/PCM params
2191     if (hfp_connection->bcm_send_write_i2spcm_interface_param){
2192         hfp_connection->bcm_send_write_i2spcm_interface_param = false;
2193         hfp_bcm_write_i2spcm_interface_param(hfp_connection);
2194         return;
2195     }
2196     // Disable WBS
2197     if (hfp_connection->bcm_send_disable_wbs){
2198         hfp_connection->bcm_send_disable_wbs = false;
2199         hci_send_cmd(&hci_bcm_enable_wbs, 0, 2);
2200         return;
2201     }
2202 #endif
2203 #ifdef ENABLE_RTK_PCM_WBS
2204     // Configure CVSD vs. mSBC
2205     if (hfp_connection->rtk_send_sco_config){
2206         hfp_connection->rtk_send_sco_config = false;
2207         if (hfp_connection->negotiated_codec == HFP_CODEC_MSBC){
2208             log_info("RTK SCO: 16k + mSBC");
2209             hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x00, 0x00, 0x41);
2210         } else {
2211             log_info("RTK SCO: 16k + CVSD");
2212             hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x0c, 0x00, 0x01);
2213         }
2214         return;
2215     }
2216 #endif
2217 #if defined (ENABLE_CC256X_ASSISTED_HFP) || defined (ENABLE_BCM_PCM_WBS)
2218     if (hfp_connection->state == HFP_W4_WBS_SHUTDOWN){
2219         hfp_finalize_connection_context(hfp_connection);
2220         return;
2221     }
2222 #endif
2223 
2224     if (!rfcomm_can_send_packet_now(hfp_connection->rfcomm_cid)) {
2225         log_info("hfp_ag_run_for_context: request can send for 0x%02x", hfp_connection->rfcomm_cid);
2226         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2227         return;
2228     }
2229 
2230     int cmd_sent = hfp_ag_send_commands(hfp_connection);
2231 
2232     if (!cmd_sent){
2233         cmd_sent = hfp_ag_run_for_context_service_level_connection(hfp_connection);
2234     }
2235 
2236     if (!cmd_sent){
2237         cmd_sent = hfp_ag_run_for_context_service_level_connection_queries(hfp_connection);
2238     }
2239 
2240     if (!cmd_sent){
2241         cmd_sent = call_setup_state_machine(hfp_connection);
2242     }
2243 
2244     if (!cmd_sent){
2245         cmd_sent = hfp_ag_run_for_audio_connection(hfp_connection);
2246     }
2247 
2248     if (!cmd_sent){
2249         cmd_sent = hfp_ag_voice_recognition_state_machine(hfp_connection);
2250     }
2251 
2252     // disconnect
2253     if (!cmd_sent && (hfp_connection->command == HFP_CMD_NONE) && (hfp_connection->state == HFP_W2_DISCONNECT_RFCOMM)){
2254         hfp_connection->state = HFP_W4_RFCOMM_DISCONNECTED;
2255         rfcomm_disconnect(hfp_connection->rfcomm_cid);
2256     }
2257 
2258     if (cmd_sent){
2259         hfp_connection->command = HFP_CMD_NONE;
2260         rfcomm_request_can_send_now_event(hfp_connection->rfcomm_cid);
2261     }
2262 }
2263 
2264 static int hfp_parser_is_end_of_line(uint8_t byte){
2265     return (byte == '\n') || (byte == '\r');
2266 }
2267 
2268 static void hfp_ag_handle_rfcomm_data(hfp_connection_t * hfp_connection, uint8_t *packet, uint16_t size){
2269     // assertion: size >= 1 as rfcomm.c does not deliver empty packets
2270     if (size < 1) return;
2271     uint8_t status = ERROR_CODE_SUCCESS;
2272 
2273     hfp_log_rfcomm_message("HFP_AG_RX", packet, size);
2274 #ifdef ENABLE_HFP_AT_MESSAGES
2275     hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_AT_MESSAGE_RECEIVED, (char *) packet);
2276 #endif
2277 
2278     // process messages byte-wise
2279     int pos;
2280     for (pos = 0; pos < size ; pos++){
2281         hfp_parse(hfp_connection, packet[pos], 0);
2282 
2283         // parse until end of line
2284         if (!hfp_parser_is_end_of_line(packet[pos])) continue;
2285 
2286         hfp_generic_status_indicator_t * indicator;
2287         switch(hfp_connection->command){
2288             case HFP_CMD_HF_ACTIVATE_VOICE_RECOGNITION:
2289                 hfp_connection->command = HFP_CMD_NONE;
2290                 hfp_connection->ag_vra_requested_by_hf = true;
2291                 break;
2292             case HFP_CMD_RESPONSE_AND_HOLD_QUERY:
2293                 hfp_connection->command = HFP_CMD_NONE;
2294                 if (hfp_ag_response_and_hold_active){
2295                     hfp_connection->send_response_and_hold_status = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD + 1;
2296                 }
2297                 hfp_connection->ok_pending = 1;
2298                 break;
2299             case HFP_CMD_RESPONSE_AND_HOLD_COMMAND:
2300                 hfp_connection->command = HFP_CMD_NONE;
2301                 switch(hfp_connection->ag_response_and_hold_action){
2302                     case HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD:
2303                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_HF, hfp_connection);
2304                         break;
2305                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_ACCEPTED:
2306                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_HF, hfp_connection);
2307                         break;
2308                     case HFP_RESPONSE_AND_HOLD_HELD_INCOMING_REJECTED:
2309                         hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_HF, hfp_connection);
2310                         break;
2311                     default:
2312                         break;
2313                 }
2314                 hfp_connection->ok_pending = 1;
2315                 break;
2316             case HFP_CMD_HF_INDICATOR_STATUS:
2317                 hfp_connection->command = HFP_CMD_NONE;
2318 
2319                 if (hfp_connection->parser_indicator_index < hfp_ag_generic_status_indicators_nr){
2320                     indicator = &hfp_ag_generic_status_indicators[hfp_connection->parser_indicator_index];
2321                     switch (indicator->uuid){
2322                         case HFP_HF_INDICATOR_UUID_ENHANCED_SAFETY:
2323                             if (hfp_connection->parser_indicator_value > 1) {
2324                                 hfp_connection->send_error = 1;
2325                                 break;
2326                             }
2327                             hfp_connection->ok_pending = 1;
2328                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2329                             break;
2330                         case HFP_HF_INDICATOR_UUID_BATTERY_LEVEL:
2331                             if (hfp_connection->parser_indicator_value > 100){
2332                                 hfp_connection->send_error = 1;
2333                                 break;
2334                             }
2335                             hfp_connection->ok_pending = 1;
2336                             hfp_ag_emit_hf_indicator_value(hfp_connection, indicator->uuid, hfp_connection->parser_indicator_value);
2337                             break;
2338                         default:
2339                             hfp_connection->send_error = 1;
2340                             break;
2341                     }
2342                 } else {
2343                     hfp_connection->send_error = 1;
2344                 }
2345                 break;
2346             case HFP_CMD_RETRIEVE_AG_INDICATORS_STATUS:
2347                 // expected by SLC state machine
2348                 if (hfp_connection->state < HFP_SERVICE_LEVEL_CONNECTION_ESTABLISHED) break;
2349                 hfp_connection->send_ag_indicators_segment = 0;
2350                 hfp_connection->send_ag_status_indicators = 1;
2351                 break;
2352             case HFP_CMD_LIST_CURRENT_CALLS:
2353                 hfp_connection->command = HFP_CMD_NONE;
2354                 hfp_connection->next_call_index = 0;
2355                 hfp_connection->send_status_of_current_calls = 1;
2356                 break;
2357             case HFP_CMD_GET_SUBSCRIBER_NUMBER_INFORMATION:
2358                 hfp_connection->command = HFP_CMD_NONE;
2359                 if (hfp_ag_subscriber_numbers_count == 0){
2360                     hfp_ag_send_ok(hfp_connection->rfcomm_cid);
2361                     break;
2362                 }
2363                 hfp_connection->next_subscriber_number_to_send = 0;
2364                 hfp_connection->send_subscriber_number = 1;
2365                 break;
2366             case HFP_CMD_TRANSMIT_DTMF_CODES:
2367             {
2368                 hfp_connection->command = HFP_CMD_NONE;
2369                 char buffer[2];
2370                 buffer[0] = (char) hfp_connection->ag_dtmf_code;
2371                 buffer[1] = 0;
2372                 hfp_emit_string_event(hfp_connection, HFP_SUBEVENT_TRANSMIT_DTMF_CODES, buffer);
2373                 break;
2374             }
2375             case HFP_CMD_HF_REQUEST_PHONE_NUMBER:
2376                 hfp_connection->command = HFP_CMD_NONE;
2377                 hfp_emit_simple_event(hfp_connection, HFP_SUBEVENT_ATTACH_NUMBER_TO_VOICE_TAG);
2378                 break;
2379             case HFP_CMD_TURN_OFF_EC_AND_NR:
2380                 hfp_connection->command = HFP_CMD_NONE;
2381 
2382                 if (get_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION)){
2383                     hfp_connection->ok_pending = 1;
2384                     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_EC_NR_FUNCTION, hfp_connection->ag_echo_and_noise_reduction);
2385                     status = ERROR_CODE_SUCCESS;
2386                 } else {
2387                     hfp_connection->send_error = 1;
2388                     status = ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2389                 }
2390                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_ECHO_CANCELING_AND_NOISE_REDUCTION_DEACTIVATE, status);
2391                 break;
2392             case HFP_CMD_CALL_ANSWERED:
2393                 hfp_connection->command = HFP_CMD_NONE;
2394                 log_info("HFP: ATA");
2395                 hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_HF, hfp_connection);
2396                 break;
2397             case HFP_CMD_HANG_UP_CALL:
2398                 hfp_connection->command = HFP_CMD_NONE;
2399                 hfp_connection->ok_pending = 1;
2400                 hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_HF, hfp_connection);
2401                 break;
2402             case HFP_CMD_CALL_HOLD: {
2403                 hfp_connection->command = HFP_CMD_NONE;
2404                 hfp_connection->ok_pending = 1;
2405 
2406                 switch (hfp_connection->ag_call_hold_action){
2407                     case 0:
2408                         // Releases all held calls or sets User Determined User Busy (UDUB) for a waiting call.
2409                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_USER_BUSY, hfp_connection);
2410                         break;
2411                     case 1:
2412                         // Releases all active calls (if any exist) and accepts the other (held or waiting) call.
2413                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2414                         // waiting call (i.e., not to the held call) in conflicting situation.
2415                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_RELEASE_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2416                         break;
2417                     case 2:
2418                         // Places all active calls (if any exist) on hold and accepts the other (held or waiting) call.
2419                         // Where both a held and a waiting call exist, the above procedures shall apply to the
2420                         // waiting call (i.e., not to the held call) in conflicting situation.
2421                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_PARK_ACTIVE_ACCEPT_HELD_OR_WAITING_CALL, hfp_connection);
2422                         break;
2423                     case 3:
2424                         // Adds a held call to the conversation.
2425                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_ADD_HELD_CALL, hfp_connection);
2426                         break;
2427                     case 4:
2428                         // Connects the two calls and disconnects the subscriber from both calls (Explicit Call Transfer).
2429                         hfp_ag_call_sm(HFP_AG_CALL_HOLD_EXIT_AND_JOIN_CALLS, hfp_connection);
2430                         break;
2431                     default:
2432                         break;
2433                 }
2434 				hfp_connection->call_index = 0;
2435                 break;
2436             }
2437             case HFP_CMD_CALL_PHONE_NUMBER:
2438                 hfp_connection->command = HFP_CMD_NONE;
2439                 hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_HF, hfp_connection);
2440                 break;
2441             case HFP_CMD_REDIAL_LAST_NUMBER:
2442                 hfp_connection->command = HFP_CMD_NONE;
2443                 hfp_ag_call_sm(HFP_AG_OUTGOING_REDIAL_INITIATED, hfp_connection);
2444                 break;
2445             case HFP_CMD_ENABLE_CLIP:
2446                 hfp_connection->command = HFP_CMD_NONE;
2447                 log_info("hfp: clip set, now: %u", hfp_connection->clip_enabled);
2448                 hfp_connection->ok_pending = 1;
2449                 break;
2450             case HFP_CMD_ENABLE_CALL_WAITING_NOTIFICATION:
2451                 hfp_connection->command = HFP_CMD_NONE;
2452                 log_info("hfp: call waiting notification set, now: %u", hfp_connection->call_waiting_notification_enabled);
2453                 hfp_connection->ok_pending = 1;
2454                 break;
2455             case HFP_CMD_SET_SPEAKER_GAIN:
2456                 hfp_connection->command = HFP_CMD_NONE;
2457                 hfp_connection->ok_pending = 1;
2458                 log_info("HF speaker gain = %u", hfp_connection->speaker_gain);
2459                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_SPEAKER_VOLUME, hfp_connection->speaker_gain);
2460                 break;
2461             case HFP_CMD_SET_MICROPHONE_GAIN:
2462                 hfp_connection->command = HFP_CMD_NONE;
2463                 hfp_connection->ok_pending = 1;
2464                 log_info("HF microphone gain = %u", hfp_connection->microphone_gain);
2465                 hfp_emit_event(hfp_connection, HFP_SUBEVENT_MICROPHONE_VOLUME, hfp_connection->microphone_gain);
2466                 break;
2467             case HFP_CMD_UNKNOWN:
2468                 hfp_connection->command = HFP_CMD_NONE;
2469                 hfp_connection->send_error = 1;
2470                 break;
2471             default:
2472                 break;
2473         }
2474     }
2475 }
2476 
2477 static void hfp_ag_run(void){
2478     btstack_linked_list_iterator_t it;
2479     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2480     while (btstack_linked_list_iterator_has_next(&it)){
2481         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2482         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2483         hfp_ag_run_for_context(hfp_connection);
2484     }
2485 }
2486 
2487 static void hfp_ag_rfcomm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2488     hfp_connection_t * hfp_connection = NULL;
2489     switch (packet_type){
2490         case RFCOMM_DATA_PACKET:
2491             hfp_connection = get_hfp_connection_context_for_rfcomm_cid(channel);
2492             btstack_assert(hfp_connection != NULL);
2493 
2494             hfp_ag_handle_rfcomm_data(hfp_connection, packet, size);
2495             hfp_ag_run_for_context(hfp_connection);
2496             return;
2497         case HCI_EVENT_PACKET:
2498             if (packet[0] == RFCOMM_EVENT_CAN_SEND_NOW){
2499                 uint16_t rfcomm_cid = rfcomm_event_can_send_now_get_rfcomm_cid(packet);
2500                 hfp_connection = get_hfp_connection_context_for_rfcomm_cid(rfcomm_cid);
2501                 btstack_assert(hfp_connection != NULL);
2502 
2503                 hfp_ag_run_for_context(hfp_connection);
2504                 return;
2505             }
2506             hfp_handle_rfcomm_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2507             break;
2508         default:
2509             break;
2510     }
2511 
2512     hfp_ag_run();
2513 }
2514 
2515 static void hfp_ag_hci_event_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
2516     hfp_handle_hci_event(packet_type, channel, packet, size, HFP_ROLE_AG);
2517     hfp_ag_run();
2518 }
2519 
2520 void hfp_ag_init_codecs(int codecs_nr, const uint8_t * codecs){
2521     if (codecs_nr > HFP_MAX_NUM_CODECS){
2522         log_error("hfp_init: codecs_nr (%d) > HFP_MAX_NUM_CODECS (%d)", codecs_nr, HFP_MAX_NUM_CODECS);
2523         return;
2524     }
2525     int i;
2526     hfp_ag_codecs_nr = codecs_nr;
2527     for (i=0; i < codecs_nr; i++){
2528         hfp_ag_codecs[i] = codecs[i];
2529     }
2530 }
2531 
2532 void hfp_ag_init_supported_features(uint32_t supported_features){
2533     hfp_ag_supported_features = supported_features;
2534 }
2535 
2536 void hfp_ag_init_ag_indicators(int ag_indicators_nr, const hfp_ag_indicator_t * ag_indicators){
2537     hfp_ag_indicators_nr = ag_indicators_nr;
2538     (void)memcpy(hfp_ag_indicators, ag_indicators,
2539                  ag_indicators_nr * sizeof(hfp_ag_indicator_t));
2540 }
2541 
2542 void hfp_ag_init_hf_indicators(int hf_indicators_nr, const hfp_generic_status_indicator_t * hf_indicators){
2543     if (hf_indicators_nr > HFP_MAX_NUM_INDICATORS) return;
2544     hfp_ag_generic_status_indicators_nr = hf_indicators_nr;
2545     (void)memcpy(hfp_ag_generic_status_indicators, hf_indicators,
2546                  hf_indicators_nr * sizeof(hfp_generic_status_indicator_t));
2547 }
2548 
2549 void hfp_ag_init_call_hold_services(int call_hold_services_nr, const char * call_hold_services[]){
2550     hfp_ag_call_hold_services_nr = call_hold_services_nr;
2551     (void)memcpy(hfp_ag_call_hold_services, call_hold_services,
2552                  call_hold_services_nr * sizeof(char *));
2553 }
2554 
2555 
2556 void hfp_ag_init(uint16_t rfcomm_channel_nr){
2557 
2558     hfp_init();
2559     hfp_ag_call_hold_services_nr = 0;
2560     hfp_ag_response_and_hold_active = false;
2561     hfp_ag_indicators_nr = 0;
2562     hfp_ag_codecs_nr = 0;
2563     hfp_ag_supported_features = HFP_DEFAULT_AG_SUPPORTED_FEATURES;
2564     hfp_ag_subscriber_numbers = NULL;
2565     hfp_ag_subscriber_numbers_count = 0;
2566 
2567     hfp_ag_hci_event_callback_registration.callback = &hfp_ag_hci_event_packet_handler;
2568     hci_add_event_handler(&hfp_ag_hci_event_callback_registration);
2569 
2570     rfcomm_register_service(&hfp_ag_rfcomm_packet_handler, rfcomm_channel_nr, 0xffff);
2571 
2572     // used to set packet handler for outgoing rfcomm connections - could be handled by emitting an event to us
2573     hfp_set_ag_rfcomm_packet_handler(&hfp_ag_rfcomm_packet_handler);
2574 
2575     hfp_gsm_init();
2576 }
2577 
2578 void hfp_ag_deinit(void){
2579     hfp_deinit();
2580     hfp_gsm_deinit();
2581 
2582     hfp_ag_callback = NULL;
2583     hfp_ag_supported_features = 0;
2584     hfp_ag_codecs_nr = 0;
2585     hfp_ag_indicators_nr = 0;
2586     hfp_ag_call_hold_services_nr = 0;
2587     (void) memset(&hfp_ag_call_hold_services, 0, sizeof(hfp_ag_call_hold_services));
2588     hfp_ag_response_and_hold_state = HFP_RESPONSE_AND_HOLD_INCOMING_ON_HOLD;
2589     (void) memset(&hfp_ag_response_and_hold_state, 0, sizeof(hfp_response_and_hold_state_t));
2590     hfp_ag_subscriber_numbers = NULL;
2591     (void) memset(&hfp_ag_hci_event_callback_registration, 0, sizeof(btstack_packet_callback_registration_t));
2592 }
2593 
2594 uint8_t hfp_ag_establish_service_level_connection(bd_addr_t bd_addr){
2595     return hfp_establish_service_level_connection(bd_addr, BLUETOOTH_SERVICE_CLASS_HANDSFREE, HFP_ROLE_AG);
2596 }
2597 
2598 uint8_t hfp_ag_release_service_level_connection(hci_con_handle_t acl_handle){
2599     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2600     if (!hfp_connection){
2601         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2602     }
2603 
2604     hfp_trigger_release_service_level_connection(hfp_connection);
2605     hfp_ag_run_for_context(hfp_connection);
2606     return ERROR_CODE_SUCCESS;
2607 }
2608 
2609 uint8_t hfp_ag_report_extended_audio_gateway_error_result_code(hci_con_handle_t acl_handle, hfp_cme_error_t error){
2610     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2611     if (!hfp_connection){
2612         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2613     }
2614 
2615     hfp_connection->extended_audio_gateway_error = 0;
2616     if (!hfp_connection->enable_extended_audio_gateway_error_report){
2617         return ERROR_CODE_COMMAND_DISALLOWED;
2618     }
2619 
2620     hfp_connection->extended_audio_gateway_error = error;
2621     hfp_ag_run_for_context(hfp_connection);
2622     return ERROR_CODE_SUCCESS;
2623 }
2624 
2625 static uint8_t hfp_ag_setup_audio_connection(hfp_connection_t * hfp_connection){
2626     if (hfp_connection->state == HFP_AUDIO_CONNECTION_ESTABLISHED){
2627         return ERROR_CODE_COMMAND_DISALLOWED;
2628     }
2629     if (hfp_connection->state >= HFP_W2_DISCONNECT_SCO){
2630         return ERROR_CODE_COMMAND_DISALLOWED;
2631     }
2632 
2633     hfp_connection->establish_audio_connection = 1;
2634     if (!has_codec_negotiation_feature(hfp_connection)){
2635         log_info("hfp_ag_establish_audio_connection - no codec negotiation feature, using CVSD");
2636         hfp_connection->negotiated_codec = HFP_CODEC_CVSD;
2637         hfp_connection->codecs_state = HFP_CODECS_EXCHANGED;
2638         // now, pick link settings
2639         hfp_init_link_settings(hfp_connection, hfp_ag_esco_s4_supported(hfp_connection));
2640 #ifdef ENABLE_CC256X_ASSISTED_HFP
2641         hfp_cc256x_prepare_for_sco(hfp_connection);
2642 #endif
2643         return ERROR_CODE_SUCCESS;
2644     }
2645 
2646     uint8_t i;
2647     bool codec_was_in_use = false;
2648     bool better_codec_can_be_used = false;
2649 
2650     for (i = 0; i<hfp_connection->remote_codecs_nr; i++){
2651         if (hfp_connection->negotiated_codec == hfp_connection->remote_codecs[i]){
2652             codec_was_in_use = true;
2653         } else if (hfp_connection->negotiated_codec < hfp_connection->remote_codecs[i]){
2654             better_codec_can_be_used = true;
2655         }
2656     }
2657 
2658     if (!codec_was_in_use || better_codec_can_be_used){
2659         hfp_connection->ag_send_common_codec = true;
2660         hfp_connection->codecs_state = HFP_CODECS_IDLE;
2661     }
2662     return ERROR_CODE_SUCCESS;
2663 }
2664 
2665 uint8_t hfp_ag_establish_audio_connection(hci_con_handle_t acl_handle){
2666     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2667     if (!hfp_connection){
2668         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2669     }
2670     uint8_t status = hfp_ag_setup_audio_connection(hfp_connection);
2671     if (status != ERROR_CODE_SUCCESS){
2672         return status;
2673     }
2674     hfp_ag_run_for_context(hfp_connection);
2675     return ERROR_CODE_SUCCESS;
2676 }
2677 
2678 uint8_t hfp_ag_release_audio_connection(hci_con_handle_t acl_handle){
2679     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2680     if (!hfp_connection){
2681         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2682     }
2683 
2684     if (hfp_connection->vra_state == HFP_VRA_VOICE_RECOGNITION_ACTIVATED){
2685         return ERROR_CODE_COMMAND_DISALLOWED;
2686     }
2687 
2688     uint8_t status = hfp_trigger_release_audio_connection(hfp_connection);
2689     if (status == ERROR_CODE_SUCCESS){
2690         hfp_ag_run_for_context(hfp_connection);
2691     }
2692     return status;
2693 }
2694 
2695 /**
2696  * @brief Enable in-band ring tone
2697  */
2698 void hfp_ag_set_use_in_band_ring_tone(int use_in_band_ring_tone){
2699     if (get_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE) == use_in_band_ring_tone){
2700         return;
2701     }
2702 
2703     hfp_ag_supported_features = store_bit(hfp_ag_supported_features, HFP_AGSF_IN_BAND_RING_TONE, use_in_band_ring_tone);
2704 
2705     btstack_linked_list_iterator_t it;
2706     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2707     while (btstack_linked_list_iterator_has_next(&it)){
2708         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2709         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2710         hfp_connection->ag_send_in_band_ring_tone_setting = true;
2711         hfp_ag_run_for_context(hfp_connection);
2712     }
2713 }
2714 
2715 /**
2716  * @brief Called from GSM
2717  */
2718 void hfp_ag_incoming_call(void){
2719     hfp_ag_call_sm(HFP_AG_INCOMING_CALL, NULL);
2720 }
2721 
2722 void hfp_ag_outgoing_call_initiated(const char * number) {
2723     UNUSED(number);
2724     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_INITIATED_BY_AG, NULL);
2725 }
2726 
2727 /**
2728  * @brief number is stored.
2729  */
2730 void hfp_ag_set_clip(uint8_t type, const char * number){
2731     hfp_gsm_handler(HFP_AG_SET_CLIP, 0, type, number);
2732 }
2733 
2734 void hfp_ag_call_dropped(void){
2735     hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2736 }
2737 
2738 // call from AG UI
2739 void hfp_ag_answer_incoming_call(void){
2740     hfp_ag_call_sm(HFP_AG_INCOMING_CALL_ACCEPTED_BY_AG, NULL);
2741 }
2742 
2743 void hfp_ag_join_held_call(void){
2744     hfp_ag_call_sm(HFP_AG_HELD_CALL_JOINED_BY_AG, NULL);
2745 }
2746 
2747 void hfp_ag_terminate_call(void){
2748     hfp_ag_call_sm(HFP_AG_TERMINATE_CALL_BY_AG, NULL);
2749 }
2750 
2751 void hfp_ag_outgoing_call_ringing(void){
2752     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_RINGING, NULL);
2753 }
2754 
2755 void hfp_ag_outgoing_call_established(void){
2756     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ESTABLISHED, NULL);
2757 }
2758 
2759 void hfp_ag_outgoing_call_rejected(void){
2760     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_REJECTED, NULL);
2761 }
2762 
2763 void hfp_ag_outgoing_call_accepted(void){
2764     hfp_ag_call_sm(HFP_AG_OUTGOING_CALL_ACCEPTED, NULL);
2765 }
2766 
2767 void hfp_ag_hold_incoming_call(void){
2768     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_INCOMING_CALL_BY_AG, NULL);
2769 }
2770 
2771 void hfp_ag_accept_held_incoming_call(void) {
2772     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_ACCEPT_HELD_CALL_BY_AG, NULL);
2773 }
2774 
2775 void hfp_ag_reject_held_incoming_call(void){
2776     hfp_ag_call_sm(HFP_AG_RESPONSE_AND_HOLD_REJECT_HELD_CALL_BY_AG, NULL);
2777 }
2778 
2779 static void hfp_ag_set_ag_indicator(const char * name, int value){
2780     int indicator_index = get_ag_indicator_index_for_name(name);
2781     if (indicator_index < 0) return;
2782     hfp_ag_indicators[indicator_index].status = value;
2783 
2784     btstack_linked_list_iterator_t it;
2785     btstack_linked_list_iterator_init(&it, hfp_get_connections());
2786     while (btstack_linked_list_iterator_has_next(&it)){
2787         hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2788         if (hfp_connection->local_role != HFP_ROLE_AG) continue;
2789         if (!hfp_connection->ag_indicators[indicator_index].enabled) {
2790             log_info("Requested AG indicator '%s' update to %u, but it is not enabled", hfp_ag_indicators[indicator_index].name, value);
2791             continue;
2792         }
2793         log_info("AG indicator '%s' changed to %u, request transfer status", hfp_ag_indicators[indicator_index].name, value);
2794         hfp_connection->ag_indicators_status_update_bitmap = store_bit(hfp_connection->ag_indicators_status_update_bitmap, indicator_index, 1);
2795         hfp_ag_run_for_context(hfp_connection);
2796     }
2797 }
2798 
2799 uint8_t hfp_ag_set_registration_status(int registration_status){
2800     if ((registration_status < 0) || (registration_status > 1)){
2801         return ERROR_CODE_COMMAND_DISALLOWED;
2802     }
2803 
2804     if ( (registration_status == 0) && (hfp_gsm_call_status() == HFP_CALL_STATUS_ACTIVE_OR_HELD_CALL_IS_PRESENT)){
2805 
2806         // if network goes away wihle a call is active:
2807         // - the  call gets dropped
2808         // - we send NO CARRIER
2809         // NOTE: the CALL=0 has to be sent before NO CARRIER
2810 
2811         hfp_ag_call_sm(HFP_AG_CALL_DROPPED, NULL);
2812 
2813         btstack_linked_list_iterator_t it;
2814         btstack_linked_list_iterator_init(&it, hfp_get_connections());
2815         while (btstack_linked_list_iterator_has_next(&it)){
2816             hfp_connection_t * hfp_connection = (hfp_connection_t *)btstack_linked_list_iterator_next(&it);
2817             hfp_connection->ag_send_no_carrier = true;
2818         }
2819     }
2820     hfp_ag_set_ag_indicator("service", registration_status);
2821     return ERROR_CODE_SUCCESS;
2822 }
2823 
2824 uint8_t hfp_ag_set_signal_strength(int signal_strength){
2825     if ((signal_strength < 0) || (signal_strength > 5)){
2826         return ERROR_CODE_COMMAND_DISALLOWED;
2827     }
2828 
2829     hfp_ag_set_ag_indicator("signal", signal_strength);
2830     return ERROR_CODE_SUCCESS;
2831 }
2832 
2833 uint8_t hfp_ag_set_roaming_status(int roaming_status){
2834     if ((roaming_status < 0) || (roaming_status > 1)){
2835         return ERROR_CODE_COMMAND_DISALLOWED;
2836     }
2837 
2838     hfp_ag_set_ag_indicator("roam", roaming_status);
2839     return ERROR_CODE_SUCCESS;
2840 }
2841 
2842 uint8_t hfp_ag_set_battery_level(int battery_level){
2843     if ((battery_level < 0) || (battery_level > 5)){
2844         return ERROR_CODE_COMMAND_DISALLOWED;
2845     }
2846     hfp_ag_set_ag_indicator("battchg", battery_level);
2847     return ERROR_CODE_SUCCESS;
2848 }
2849 
2850 uint8_t hfp_ag_activate_voice_recognition(hci_con_handle_t acl_handle){
2851     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2852     if (!hfp_connection){
2853         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2854     }
2855 
2856     if (hfp_connection->emit_vra_enabled_after_audio_established){
2857         return ERROR_CODE_COMMAND_DISALLOWED;
2858     }
2859 
2860     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2861     bool legacy_vra_supported   = hfp_ag_vra_flag_supported(hfp_connection);
2862     if (!enhanced_vra_supported && !legacy_vra_supported){
2863         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2864     }
2865 
2866     if (!hfp_ag_can_activate_voice_recognition(hfp_connection)){
2867         return ERROR_CODE_COMMAND_DISALLOWED;
2868     }
2869 
2870     hfp_connection->ag_activate_voice_recognition_value = 1;
2871     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_ACTIVATED;
2872     hfp_connection->enhanced_voice_recognition_enabled = enhanced_vra_supported;
2873     hfp_connection->ag_audio_connection_opened_before_vra = hfp_ag_is_audio_connection_active(hfp_connection);
2874     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2875     hfp_connection->ag_vra_send_command = true;
2876     hfp_ag_run_for_context(hfp_connection);
2877     return ERROR_CODE_SUCCESS;
2878 }
2879 
2880 uint8_t hfp_ag_deactivate_voice_recognition(hci_con_handle_t acl_handle){
2881     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2882     if (!hfp_connection){
2883         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2884     }
2885 
2886     if (hfp_connection->emit_vra_enabled_after_audio_established){
2887         return ERROR_CODE_COMMAND_DISALLOWED;
2888     }
2889 
2890     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2891     bool legacy_vra_supported = hfp_ag_vra_flag_supported(hfp_connection);
2892 
2893     if (!enhanced_vra_supported && !legacy_vra_supported){
2894         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2895     }
2896 
2897     if (!hfp_ag_voice_recognition_session_active(hfp_connection)){
2898         return ERROR_CODE_COMMAND_DISALLOWED;
2899     }
2900 
2901     hfp_connection->ag_activate_voice_recognition_value = 0;
2902     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_VOICE_RECOGNITION_OFF;
2903     hfp_connection->ag_vra_state = HFP_VOICE_RECOGNITION_STATE_AG_READY;
2904     hfp_connection->ag_vra_send_command = true;
2905     hfp_ag_run_for_context(hfp_connection);
2906     return ERROR_CODE_SUCCESS;
2907 }
2908 
2909 static uint8_t hfp_ag_enhanced_voice_recognition_send_state(hci_con_handle_t acl_handle, hfp_voice_recognition_state_t state){
2910     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2911     if (!hfp_connection){
2912         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2913     }
2914 
2915     if (hfp_connection->emit_vra_enabled_after_audio_established){
2916         return ERROR_CODE_COMMAND_DISALLOWED;
2917     }
2918 
2919     if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED){
2920         return ERROR_CODE_COMMAND_DISALLOWED;
2921     }
2922 
2923     if (hfp_connection->vra_state != HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
2924         return ERROR_CODE_COMMAND_DISALLOWED;
2925     }
2926 
2927     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2928     if (!enhanced_vra_supported ){
2929         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2930     }
2931 
2932 
2933     hfp_connection->ag_vra_state = state;
2934     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_STATUS;
2935     hfp_connection->ag_vra_send_command = true;
2936     hfp_ag_run_for_context(hfp_connection);
2937     return ERROR_CODE_SUCCESS;
2938 }
2939 
2940 uint8_t hfp_ag_enhanced_voice_recognition_report_sending_audio(hci_con_handle_t acl_handle){
2941     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_STARTING_SOUND);
2942 }
2943 uint8_t hfp_ag_enhanced_voice_recognition_report_ready_for_audio(hci_con_handle_t acl_handle){
2944     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_READY_TO_ACCEPT_AUDIO_INPUT);
2945 }
2946 uint8_t hfp_ag_enhanced_voice_recognition_report_processing_input(hci_con_handle_t acl_handle){
2947     return hfp_ag_enhanced_voice_recognition_send_state(acl_handle, HFP_VOICE_RECOGNITION_STATE_AG_IS_PROCESSING_AUDIO_INPUT);
2948 }
2949 
2950 
2951 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){
2952     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
2953     if (!hfp_connection){
2954         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
2955     }
2956 
2957     if (hfp_connection->emit_vra_enabled_after_audio_established){
2958         return ERROR_CODE_COMMAND_DISALLOWED;
2959     }
2960 
2961     if (hfp_connection->state != HFP_AUDIO_CONNECTION_ESTABLISHED){
2962         return ERROR_CODE_COMMAND_DISALLOWED;
2963     }
2964 
2965     if (hfp_connection->vra_state != HFP_VRA_ENHANCED_VOICE_RECOGNITION_READY_FOR_AUDIO){
2966         return ERROR_CODE_COMMAND_DISALLOWED;
2967     }
2968 
2969     bool enhanced_vra_supported = hfp_ag_enhanced_vra_flag_supported(hfp_connection);
2970     if (!enhanced_vra_supported ){
2971         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2972     }
2973 
2974     bool enhanced_vra_msg_supported = hfp_ag_can_send_enhanced_vra_message_flag_supported(hfp_connection);
2975     if (!enhanced_vra_msg_supported ){
2976         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2977     }
2978 
2979     uint16_t message_len = strlen(msg.text);
2980 
2981     if (message_len > HFP_MAX_VR_TEXT_SIZE){
2982         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2983     }
2984 
2985     if ((HFP_VR_TEXT_HEADER_SIZE + message_len) > hfp_connection->rfcomm_mtu){
2986         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
2987     }
2988 
2989     hfp_connection->vra_state_requested = HFP_VRA_W2_SEND_ENHANCED_VOICE_RECOGNITION_MSG;
2990     hfp_connection->ag_msg = msg;
2991     hfp_connection->ag_vra_state = state;
2992     hfp_connection->ag_vra_send_command = true;
2993     hfp_ag_run_for_context(hfp_connection);
2994 
2995     return ERROR_CODE_SUCCESS;
2996 }
2997 
2998 
2999 uint8_t hfp_ag_set_microphone_gain(hci_con_handle_t acl_handle, int gain){
3000     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3001     if (!hfp_connection){
3002         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3003     }
3004 
3005     if ((gain < 0) || (gain > 15)){
3006         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
3007         return ERROR_CODE_COMMAND_DISALLOWED;
3008     }
3009 
3010     if (hfp_connection->microphone_gain != gain){
3011         hfp_connection->microphone_gain = gain;
3012         hfp_connection->send_microphone_gain = 1;
3013     }
3014     hfp_ag_run_for_context(hfp_connection);
3015     return ERROR_CODE_SUCCESS;
3016 }
3017 
3018 uint8_t hfp_ag_set_speaker_gain(hci_con_handle_t acl_handle, int gain){
3019     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3020     if (!hfp_connection){
3021         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3022     }
3023 
3024     if ((gain < 0) || (gain > 15)){
3025         log_info("Valid range for a gain is [0..15]. Currently sent: %d", gain);
3026         return ERROR_CODE_COMMAND_DISALLOWED;
3027     }
3028 
3029     if (hfp_connection->speaker_gain != gain){
3030         hfp_connection->speaker_gain = gain;
3031         hfp_connection->send_speaker_gain = 1;
3032     }
3033     hfp_ag_run_for_context(hfp_connection);
3034     return ERROR_CODE_SUCCESS;
3035 }
3036 
3037 uint8_t hfp_ag_send_phone_number_for_voice_tag(hci_con_handle_t acl_handle, const char * number){
3038     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3039     if (!hfp_connection){
3040         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3041     }
3042 
3043     hfp_ag_set_clip(0, number);
3044     hfp_connection->send_phone_number_for_voice_tag = 1;
3045     return ERROR_CODE_SUCCESS;
3046 }
3047 
3048 uint8_t hfp_ag_reject_phone_number_for_voice_tag(hci_con_handle_t acl_handle){
3049     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3050     if (!hfp_connection){
3051         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3052     }
3053 
3054     hfp_connection->send_error = 1;
3055     return ERROR_CODE_SUCCESS;
3056 }
3057 
3058 uint8_t hfp_ag_send_dtmf_code_done(hci_con_handle_t acl_handle){
3059     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3060     if (!hfp_connection){
3061         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3062     }
3063 
3064     hfp_connection->ok_pending = 1;
3065     return ERROR_CODE_SUCCESS;
3066 }
3067 
3068 void hfp_ag_set_subcriber_number_information(hfp_phone_number_t * numbers, int numbers_count){
3069     hfp_ag_subscriber_numbers = numbers;
3070     hfp_ag_subscriber_numbers_count = numbers_count;
3071 }
3072 
3073 void hfp_ag_clear_last_dialed_number(void){
3074     hfp_gsm_clear_last_dialed_number();
3075 }
3076 
3077 void hfp_ag_set_last_dialed_number(const char * number){
3078     hfp_gsm_set_last_dialed_number(number);
3079 }
3080 
3081 uint8_t hfp_ag_notify_incoming_call_waiting(hci_con_handle_t acl_handle){
3082     hfp_connection_t * hfp_connection = get_hfp_ag_connection_context_for_acl_handle(acl_handle);
3083     if (!hfp_connection){
3084         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3085     }
3086 
3087     if (!hfp_connection->call_waiting_notification_enabled){
3088         return ERROR_CODE_COMMAND_DISALLOWED;
3089     }
3090 
3091     hfp_connection->ag_notify_incoming_call_waiting = 1;
3092     hfp_ag_run_for_context(hfp_connection);
3093     return ERROR_CODE_SUCCESS;
3094 }
3095 
3096 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){
3097 	if (!name){
3098 		name = hfp_ag_default_service_name;
3099 	}
3100 	hfp_create_sdp_record(service, service_record_handle, BLUETOOTH_SERVICE_CLASS_HANDSFREE_AUDIO_GATEWAY, rfcomm_channel_nr, name);
3101 
3102 	/*
3103 	 * 0x01 – Ability to reject a call
3104 	 * 0x00 – No ability to reject a call
3105 	 */
3106 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0301);    // Hands-Free Profile - Network
3107 	de_add_number(service, DE_UINT, DE_SIZE_8, ability_to_reject_call);
3108 
3109 	// Construct SupportedFeatures for SDP bitmap:
3110 	//
3111 	// "The values of the “SupportedFeatures” bitmap given in Table 5.4 shall be the same as the values
3112 	//  of the Bits 0 to 4 of the unsolicited result code +BRSF"
3113 	//
3114 	// Wide band speech (bit 5) requires Codec negotiation
3115 	//
3116 	uint16_t sdp_features = supported_features & 0x1f;
3117 	if ( (wide_band_speech == 1) && (supported_features & (1 << HFP_AGSF_CODEC_NEGOTIATION))){
3118 		sdp_features |= 1 << 5;
3119 	}
3120 
3121     if (supported_features & (1 << HFP_AGSF_ENHANCED_VOICE_RECOGNITION_STATUS)){
3122         sdp_features |= 1 << 6;
3123     }
3124 
3125     if (supported_features & (1 << HFP_AGSF_VOICE_RECOGNITION_TEXT)){
3126         sdp_features |= 1 << 7;
3127     }
3128 
3129 	de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311);    // Hands-Free Profile - SupportedFeatures
3130 	de_add_number(service, DE_UINT, DE_SIZE_16, sdp_features);
3131 }
3132 
3133 void hfp_ag_register_packet_handler(btstack_packet_handler_t callback){
3134 	btstack_assert(callback != NULL);
3135 
3136 	hfp_ag_callback = callback;
3137 	hfp_set_ag_callback(callback);
3138 }
3139