xref: /btstack/src/classic/hsp_ag.c (revision f9f2075ceac5e9dc08e9abea437e43d733a3a0ea)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 // *****************************************************************************
39 //
40 // HSP Audio Gateway
41 //
42 // *****************************************************************************
43 
44 #include "btstack_config.h"
45 
46 #include <stdint.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
51 #include "btstack_debug.h"
52 #include "btstack_event.h"
53 #include "btstack_memory.h"
54 #include "btstack_run_loop.h"
55 #include "classic/core.h"
56 #include "classic/sdp_server.h"
57 #include "classic/sdp_client_rfcomm.h"
58 #include "classic/sdp_util.h"
59 #include "hci.h"
60 #include "hci_cmd.h"
61 #include "hci_dump.h"
62 #include "hsp_ag.h"
63 #include "l2cap.h"
64 
65 #define HSP_HS_BUTTON_PRESS "AT+CKPD=200"
66 #define HSP_HS_AT_CKPD "AT+CKPD\r\n"
67 #define HSP_AG_OK "\r\nOK\r\n"
68 #define HSP_AG_ERROR "\r\nERROR\r\n"
69 #define HSP_AG_RING "\r\nRING\r\n"
70 #define HSP_MICROPHONE_GAIN "+VGM"
71 #define HSP_SPEAKER_GAIN "+VGS"
72 
73 #define HSP_HS_MICROPHONE_GAIN "AT+VGM="
74 #define HSP_HS_SPEAKER_GAIN "AT+VGS="
75 
76 static const char default_hsp_ag_service_name[] = "Audio Gateway";
77 
78 static bd_addr_t remote;
79 static bd_addr_t sco_event_addr;
80 static uint8_t channel_nr = 0;
81 
82 static uint16_t mtu;
83 static uint16_t rfcomm_cid = 0;
84 static uint16_t sco_handle = 0;
85 static uint16_t rfcomm_handle = 0;
86 static btstack_timer_source_t hs_timeout;
87 
88 static int ag_microphone_gain = -1;
89 static int ag_speaker_gain = -1;
90 static uint8_t ag_ring = 0;
91 static uint8_t ag_send_ok = 0;
92 static uint8_t ag_send_error = 0;
93 static uint8_t ag_num_button_press_received = 0;
94 static uint8_t ag_support_custom_commands = 0;
95 static uint8_t ag_establish_sco = 0;
96 static uint8_t hsp_disconnect_rfcomm = 0;
97 static uint8_t hsp_establish_audio_connection = 0;
98 static uint8_t hsp_release_audio_connection = 0;
99 
100 static btstack_packet_callback_registration_t hci_event_callback_registration;
101 
102 typedef enum {
103     HSP_IDLE,
104     HSP_SDP_QUERY_RFCOMM_CHANNEL,
105     HSP_W4_SDP_EVENT_QUERY_COMPLETE,
106     HSP_W4_RFCOMM_CONNECTED,
107 
108     HSP_RFCOMM_CONNECTION_ESTABLISHED,
109 
110     HSP_W4_RING_ANSWER,
111     HSP_W4_USER_ACTION,
112     HSP_W2_CONNECT_SCO,
113     HSP_W4_SCO_CONNECTED,
114 
115     HSP_AUDIO_CONNECTION_ESTABLISHED,
116 
117     HSP_W2_DISCONNECT_SCO,
118     HSP_W4_SCO_DISCONNECTED,
119 
120     HSP_W2_DISCONNECT_RFCOMM,
121     HSP_W4_RFCOMM_DISCONNECTED,
122     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
123 } hsp_state_t;
124 
125 static hsp_state_t hsp_state = HSP_IDLE;
126 
127 
128 static btstack_packet_handler_t hsp_ag_callback;
129 
130 static void hsp_run(void);
131 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
132 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
133 
134 static void dummy_notify(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t size){
135     UNUSED(packet_type);
136     UNUSED(channel);
137     UNUSED(event);
138     UNUSED(size);
139 }
140 
141 void hsp_ag_register_packet_handler(btstack_packet_handler_t callback){
142     if (callback == NULL){
143         callback = &dummy_notify;
144     }
145     hsp_ag_callback = callback;
146 }
147 
148 static void emit_event(uint8_t event_subtype, uint8_t value){
149     if (!hsp_ag_callback) return;
150     uint8_t event[4];
151     event[0] = HCI_EVENT_HSP_META;
152     event[1] = sizeof(event) - 2;
153     event[2] = event_subtype;
154     event[3] = value; // status 0 == OK
155     (*hsp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
156 }
157 
158 static void emit_event_audio_connected(uint8_t status, uint16_t handle){
159     if (!hsp_ag_callback) return;
160     uint8_t event[6];
161     event[0] = HCI_EVENT_HSP_META;
162     event[1] = sizeof(event) - 2;
163     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
164     event[3] = status;
165     little_endian_store_16(event, 4, handle);
166     (*hsp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
167 }
168 
169 void hsp_ag_create_sdp_record(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr, const char * name){
170     uint8_t* attribute;
171     de_create_sequence(service);
172 
173     // 0x0000 "Service Record Handle"
174     de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
175     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
176 
177     // 0x0001 "Service Class ID List"
178     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
179     attribute = de_push_sequence(service);
180     {
181         //  "UUID for PAN Service"
182         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_AG);
183         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio);
184     }
185     de_pop_sequence(service, attribute);
186 
187     // 0x0004 "Protocol Descriptor List"
188     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
189     attribute = de_push_sequence(service);
190     {
191         uint8_t* l2cpProtocol = de_push_sequence(attribute);
192         {
193             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
194         }
195         de_pop_sequence(attribute, l2cpProtocol);
196 
197         uint8_t* rfcomm = de_push_sequence(attribute);
198         {
199             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol);  // rfcomm_service
200             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
201         }
202         de_pop_sequence(attribute, rfcomm);
203     }
204     de_pop_sequence(service, attribute);
205 
206     // 0x0005 "Public Browse Group"
207     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
208     attribute = de_push_sequence(service);
209     {
210         de_add_number(attribute,  DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
211     }
212     de_pop_sequence(service, attribute);
213 
214     // 0x0009 "Bluetooth Profile Descriptor List"
215     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
216     attribute = de_push_sequence(service);
217     {
218         uint8_t *sppProfile = de_push_sequence(attribute);
219         {
220             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, SDP_HSP);
221             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
222         }
223         de_pop_sequence(attribute, sppProfile);
224     }
225     de_pop_sequence(service, attribute);
226 
227     // 0x0100 "Service Name"
228     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
229     if (name){
230         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
231     } else {
232         de_add_data(service,  DE_STRING, strlen(default_hsp_ag_service_name), (uint8_t *) default_hsp_ag_service_name);
233     }
234 }
235 
236 static int hsp_ag_send_str_over_rfcomm(const uint16_t cid, char * command){
237     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
238     if (err){
239         log_error("rfcomm_send_internal -> error 0X%02x", err);
240         return err;
241     }
242     return err;
243 }
244 
245 void hsp_ag_enable_custom_commands(int enable){
246     ag_support_custom_commands = enable;
247 }
248 
249 int hsp_ag_send_result(char * result){
250     if (!ag_support_custom_commands) return 1;
251     return hsp_ag_send_str_over_rfcomm(rfcomm_cid, result);
252 }
253 
254 static void hsp_ag_reset_state(void){
255     hsp_state = HSP_IDLE;
256 
257     rfcomm_cid = 0;
258     rfcomm_handle = 0;
259     sco_handle = 0;
260 
261     ag_send_ok = 0;
262     ag_send_error = 0;
263     ag_ring = 0;
264 
265     ag_num_button_press_received = 0;
266     ag_support_custom_commands = 0;
267 
268     ag_microphone_gain = -1;
269     ag_speaker_gain = -1;
270 
271     hsp_disconnect_rfcomm = 0;
272     hsp_establish_audio_connection = 0;
273     hsp_release_audio_connection = 0;
274 }
275 
276 void hsp_ag_init(uint8_t rfcomm_channel_nr){
277     // register for HCI events
278     hci_event_callback_registration.callback = &packet_handler;
279     hci_add_event_handler(&hci_event_callback_registration);
280 
281     rfcomm_register_service(packet_handler, rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
282 
283     hsp_ag_reset_state();
284 }
285 
286 void hsp_ag_connect(bd_addr_t bd_addr){
287     if (hsp_state != HSP_IDLE) return;
288     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
289     memcpy(remote, bd_addr, 6);
290     hsp_run();
291 }
292 
293 void hsp_ag_disconnect(void){
294     hsp_ag_release_audio_connection();
295     if (hsp_state < HSP_W4_RFCOMM_CONNECTED){
296         hsp_state = HSP_IDLE;
297         return;
298     }
299 
300     if (hsp_state == HSP_W4_RFCOMM_CONNECTED){
301         hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
302         return;
303     }
304     hsp_disconnect_rfcomm = 1;
305     hsp_run();
306 }
307 
308 void hsp_ag_establish_audio_connection(void){
309     switch (hsp_state){
310         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
311             hsp_establish_audio_connection = 1;
312             hsp_state = HSP_W4_SCO_CONNECTED;
313             break;
314         case HSP_W4_RFCOMM_CONNECTED:
315             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
316             break;
317         default:
318             break;
319     }
320     hsp_run();
321 }
322 
323 void hsp_ag_release_audio_connection(void){
324     if (hsp_state >= HSP_W2_DISCONNECT_SCO) return;
325     if (hsp_state < HSP_AUDIO_CONNECTION_ESTABLISHED) return;
326 
327     hsp_release_audio_connection = 1;
328     hsp_run();
329 }
330 
331 
332 void hsp_ag_set_microphone_gain(uint8_t gain){
333     if (gain < 0 || gain >15) {
334         log_error("Gain must be in interval [0..15], it is given %d", gain);
335         return;
336     }
337     ag_microphone_gain = gain;
338     hsp_run();
339 }
340 
341 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
342 void hsp_ag_set_speaker_gain(uint8_t gain){
343     if (gain < 0 || gain >15) {
344         log_error("Gain must be in interval [0..15], it is given %d", gain);
345         return;
346     }
347     ag_speaker_gain = gain;
348     hsp_run();
349 }
350 
351 static void hsp_ringing_timeout_handler(btstack_timer_source_t * timer){
352     UNUSED(timer);
353 
354     ag_ring = 1;
355     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
356     btstack_run_loop_add_timer(&hs_timeout);
357     hsp_run();
358 }
359 
360 static void hsp_ringing_timer_start(void){
361     btstack_run_loop_remove_timer(&hs_timeout);
362     btstack_run_loop_set_timer_handler(&hs_timeout, hsp_ringing_timeout_handler);
363     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
364     btstack_run_loop_add_timer(&hs_timeout);
365 }
366 
367 static void hsp_ringing_timer_stop(void){
368     btstack_run_loop_remove_timer(&hs_timeout);
369 }
370 
371 void hsp_ag_start_ringing(void){
372     ag_ring = 1;
373     if (hsp_state == HSP_W2_CONNECT_SCO) {
374         hsp_state = HSP_W4_RING_ANSWER;
375     }
376     hsp_ringing_timer_start();
377 }
378 
379 void hsp_ag_stop_ringing(void){
380     ag_ring = 0;
381     if (hsp_state == HSP_W4_RING_ANSWER){
382         hsp_state = HSP_W2_CONNECT_SCO;
383     }
384     hsp_ringing_timer_stop();
385 }
386 
387 static void hsp_run(void){
388     if (ag_establish_sco && hci_can_send_command_packet_now()){
389         ag_establish_sco = 0;
390 
391         log_info("HSP: sending hci_accept_connection_request.");
392         // remote supported feature eSCO is set if link type is eSCO
393         // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
394         uint16_t max_latency;
395         uint8_t  retransmission_effort;
396         uint16_t packet_types;
397 
398         if (hci_remote_esco_supported(rfcomm_handle)){
399             max_latency = 0x000c;
400             retransmission_effort = 0x02;
401             packet_types = 0x388;
402         } else {
403             max_latency = 0xffff;
404             retransmission_effort = 0xff;
405             packet_types = 0x003f;
406         }
407 
408         uint16_t sco_voice_setting = hci_get_sco_voice_setting();
409 
410         log_info("HFP: sending hci_accept_connection_request, sco_voice_setting %02x", sco_voice_setting);
411         hci_send_cmd(&hci_accept_synchronous_connection, remote, 8000, 8000, max_latency,
412                         sco_voice_setting, retransmission_effort, packet_types);
413         return;
414     }
415 
416     if (ag_send_ok){
417         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
418             rfcomm_request_can_send_now_event(rfcomm_cid);
419             return;
420         }
421         ag_send_ok = 0;
422         hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
423         return;
424     }
425 
426     if (ag_send_error){
427         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
428             rfcomm_request_can_send_now_event(rfcomm_cid);
429             return;
430         }
431         ag_send_error = 0;
432         hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
433         return;
434     }
435 
436     if (ag_ring){
437         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
438             rfcomm_request_can_send_now_event(rfcomm_cid);
439             return;
440         }
441         ag_ring = 0;
442         hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
443         return;
444     }
445 
446     if (hsp_establish_audio_connection){
447         if (!hci_can_send_command_packet_now()) return;
448         hsp_establish_audio_connection = 0;
449         hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
450         return;
451     }
452 
453     if (hsp_release_audio_connection){
454         hsp_release_audio_connection = 0;
455         gap_disconnect(sco_handle);
456         return;
457     }
458 
459     if (hsp_disconnect_rfcomm){
460         hsp_disconnect_rfcomm = 0;
461         hsp_establish_audio_connection = 0;
462         rfcomm_disconnect(rfcomm_cid);
463         return;
464     }
465 
466     switch (hsp_state){
467         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
468             hsp_state = HSP_W4_SDP_EVENT_QUERY_COMPLETE;
469             log_info("Start SDP query %s, 0x%02x", bd_addr_to_str(remote), SDP_HSP);
470             sdp_client_query_rfcomm_channel_and_name_for_uuid(&handle_query_rfcomm_event, remote, SDP_HSP);
471             break;
472 
473         case HSP_W4_RING_ANSWER:
474             if (!ag_num_button_press_received) break;
475 
476             if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
477                 rfcomm_request_can_send_now_event(rfcomm_cid);
478                 return;
479             }
480 
481             ag_send_ok = 0;
482             ag_num_button_press_received = 0;
483             hsp_state = HSP_W2_CONNECT_SCO;
484 
485             hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
486             break;
487 
488         case HSP_W2_CONNECT_SCO:
489             if (!hci_can_send_command_packet_now()) return;
490             hsp_state = HSP_W4_SCO_CONNECTED;
491             hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
492             break;
493 
494         case HSP_W2_DISCONNECT_SCO:
495             ag_num_button_press_received = 0;
496 
497             hsp_state = HSP_W4_SCO_DISCONNECTED;
498             gap_disconnect(sco_handle);
499             break;
500 
501         case HSP_W2_DISCONNECT_RFCOMM:
502             rfcomm_disconnect(rfcomm_cid);
503             break;
504 
505         case HSP_AUDIO_CONNECTION_ESTABLISHED:
506         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
507 
508             if (ag_microphone_gain >= 0){
509                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
510                     rfcomm_request_can_send_now_event(rfcomm_cid);
511                     return;
512                 }
513                 int gain = ag_microphone_gain;
514                 ag_microphone_gain = -1;
515                 char buffer[10];
516                 sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, gain);
517                 hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
518                 break;
519             }
520 
521             if (ag_speaker_gain >= 0){
522                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
523                     rfcomm_request_can_send_now_event(rfcomm_cid);
524                     return;
525                 }
526                 int gain = ag_speaker_gain;
527                 ag_speaker_gain = -1;
528                 char buffer[10];
529                 sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, gain);
530                 hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
531                 break;
532             }
533             break;
534         default:
535             break;
536     }
537 }
538 
539 
540 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
541     UNUSED(channel);
542 
543     if (packet_type == RFCOMM_DATA_PACKET){
544         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
545             size--;
546             packet++;
547         }
548 
549         if (strncmp((char *)packet, HSP_HS_BUTTON_PRESS, strlen(HSP_HS_BUTTON_PRESS)) == 0){
550             log_info("Received button press %s", HSP_HS_BUTTON_PRESS);
551             ag_send_ok = 1;
552             switch (hsp_state){
553                 case HSP_AUDIO_CONNECTION_ESTABLISHED:
554                     hsp_release_audio_connection = 1;
555                     break;
556                 case HSP_RFCOMM_CONNECTION_ESTABLISHED:
557                     hsp_establish_audio_connection = 1;
558                     break;
559                 default:
560                     break;
561             }
562         } else if (strncmp((char *)packet, HSP_HS_MICROPHONE_GAIN, strlen(HSP_HS_MICROPHONE_GAIN)) == 0){
563             uint8_t gain = (uint8_t)btstack_atoi((char*)&packet[strlen(HSP_HS_MICROPHONE_GAIN)]);
564             ag_send_ok = 1;
565             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
566 
567         } else if (strncmp((char *)packet, HSP_HS_SPEAKER_GAIN, strlen(HSP_HS_SPEAKER_GAIN)) == 0){
568             uint8_t gain = (uint8_t)btstack_atoi((char*)&packet[strlen(HSP_HS_SPEAKER_GAIN)]);
569             ag_send_ok = 1;
570             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
571 
572         } else if (strncmp((char *)packet, "AT+", 3) == 0){
573             ag_send_error = 1;
574             if (!hsp_ag_callback) return;
575             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
576             uint8_t * event = packet - 4;
577             event[0] = HCI_EVENT_HSP_META;
578             event[1] = size + 2;
579             event[2] = HSP_SUBEVENT_HS_COMMAND;
580             event[3] = size;
581             (*hsp_ag_callback)(HCI_EVENT_PACKET, 0, event, size+4);
582         }
583 
584         hsp_run();
585         return;
586     }
587 
588     if (packet_type != HCI_EVENT_PACKET) return;
589     uint8_t event = hci_event_packet_get_type(packet);
590     bd_addr_t event_addr;
591     uint16_t handle;
592 
593     switch (event) {
594         case HCI_EVENT_CONNECTION_REQUEST:
595             hci_event_connection_request_get_bd_addr(packet, sco_event_addr);
596             ag_establish_sco = 1;
597             break;
598         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
599             uint8_t status = hci_event_synchronous_connection_complete_get_status(packet);
600             if (status != 0){
601                 log_error("(e)SCO Connection failed, status %u", status);
602                 emit_event_audio_connected(status, sco_handle);
603                 break;
604             }
605 
606             hci_event_synchronous_connection_complete_get_bd_addr(packet, event_addr);
607             sco_handle = hci_event_synchronous_connection_complete_get_handle(packet);
608             uint8_t  link_type = hci_event_synchronous_connection_complete_get_link_type(packet);
609             uint8_t  transmission_interval = hci_event_synchronous_connection_complete_get_transmission_interval(packet);  // measured in slots
610             uint8_t  retransmission_interval = hci_event_synchronous_connection_complete_get_retransmission_interval(packet);// measured in slots
611             uint16_t rx_packet_length = hci_event_synchronous_connection_complete_get_rx_packet_length(packet); // measured in bytes
612             uint16_t tx_packet_length = hci_event_synchronous_connection_complete_get_tx_packet_length(packet); // measured in bytes
613             uint8_t  air_mode = hci_event_synchronous_connection_complete_get_air_mode(packet);
614 
615             switch (link_type){
616                 case 0x00:
617                     log_info("SCO Connection established.");
618                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
619                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
620                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
621                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
622                     break;
623                 case 0x02:
624                     log_info("eSCO Connection established.");
625                     break;
626                 default:
627                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
628                     break;
629             }
630             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
631                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
632                  bd_addr_to_str(event_addr), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
633 
634             if (hsp_state == HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
635                 hsp_state = HSP_W2_DISCONNECT_SCO;
636                 break;
637             }
638 
639             hsp_state = HSP_AUDIO_CONNECTION_ESTABLISHED;
640             emit_event_audio_connected(status, sco_handle);
641             break;
642         }
643 
644         case RFCOMM_EVENT_INCOMING_CONNECTION:
645             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
646             if (hsp_state != HSP_IDLE) return;
647 
648             rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr);
649             rfcomm_cid = rfcomm_event_incoming_connection_get_server_channel(packet);
650             log_info("RFCOMM channel %u requested for %s", packet[8], bd_addr_to_str(event_addr));
651             hsp_state = HSP_W4_RFCOMM_CONNECTED;
652             rfcomm_accept_connection(rfcomm_cid);
653             break;
654 
655         case RFCOMM_EVENT_CHANNEL_OPENED:
656             log_info("RFCOMM_EVENT_CHANNEL_OPENED packet_handler type %u, packet[0] %x", packet_type, packet[0]);
657             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
658             if (rfcomm_event_channel_opened_get_status(packet)) {
659                 log_info("RFCOMM channel open failed, status %u§", rfcomm_event_channel_opened_get_status(packet));
660                 hsp_ag_reset_state();
661                 hsp_state = HSP_IDLE;
662             } else {
663                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
664                 rfcomm_handle = rfcomm_event_channel_opened_get_con_handle(packet);
665                 rfcomm_cid = rfcomm_event_channel_opened_get_rfcomm_cid(packet);
666                 mtu = rfcomm_event_channel_opened_get_max_frame_size(packet);
667                 log_info("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, state %d", rfcomm_cid, mtu, hsp_state);
668                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
669             }
670             emit_event(HSP_SUBEVENT_RFCOMM_CONNECTION_COMPLETE, packet[2]);
671             break;
672 
673         case RFCOMM_EVENT_CHANNEL_CLOSED:
674             rfcomm_handle = 0;
675             hsp_state = HSP_IDLE;
676             hsp_ag_reset_state();
677             emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE,0);
678             break;
679 
680         case RFCOMM_EVENT_CAN_SEND_NOW:
681             hsp_run();
682             break;
683 
684         case HCI_EVENT_DISCONNECTION_COMPLETE:
685             handle = little_endian_read_16(packet,3);
686             if (handle == sco_handle){
687                 sco_handle = 0;
688                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
689                 emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
690                 break;
691             }
692             if (handle == rfcomm_handle) {
693                 rfcomm_handle = 0;
694                 hsp_state = HSP_IDLE;
695                 hsp_ag_reset_state();
696                 emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE,0);
697             }
698             break;
699 
700         default:
701             break;
702     }
703 
704     hsp_run();
705 }
706 
707 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
708     UNUSED(packet_type);
709     UNUSED(channel);
710     UNUSED(size);
711 
712     switch (packet[0]){
713         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
714             channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
715             log_info("** Service name: '%s', RFCOMM port %u", sdp_event_query_rfcomm_service_get_name(packet), channel_nr);
716             break;
717         case SDP_EVENT_QUERY_COMPLETE:
718             if (channel_nr > 0){
719                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
720                 log_info("RFCOMM create channel. state %d", HSP_W4_RFCOMM_CONNECTED);
721                 rfcomm_create_channel(packet_handler, remote, channel_nr, NULL);
722                 break;
723             }
724             hsp_ag_reset_state();
725             log_info("Service not found, status %u.\n", sdp_event_query_complete_get_status(packet));
726             if (sdp_event_query_complete_get_status(packet)){
727                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, sdp_event_query_complete_get_status(packet));
728             } else {
729                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
730             }
731             break;
732         default:
733             break;
734     }
735 }
736 
737 
738