xref: /btstack/src/classic/hsp_ag.c (revision ab2c6ae4b737d5e801d3defe4117331eb244ebb7)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "hsp_ag.c"
39 
40 // *****************************************************************************
41 //
42 // HSP Audio Gateway
43 //
44 // *****************************************************************************
45 
46 #include "btstack_config.h"
47 
48 #include <stdint.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 
53 #include "btstack_debug.h"
54 #include "btstack_event.h"
55 #include "btstack_memory.h"
56 #include "btstack_run_loop.h"
57 #include "classic/core.h"
58 #include "classic/sdp_server.h"
59 #include "classic/sdp_client_rfcomm.h"
60 #include "classic/sdp_util.h"
61 #include "hci.h"
62 #include "hci_cmd.h"
63 #include "hci_dump.h"
64 #include "hsp_ag.h"
65 #include "l2cap.h"
66 
67 #define HSP_HS_BUTTON_PRESS "AT+CKPD=200"
68 #define HSP_HS_AT_CKPD "AT+CKPD\r\n"
69 #define HSP_AG_OK "\r\nOK\r\n"
70 #define HSP_AG_ERROR "\r\nERROR\r\n"
71 #define HSP_AG_RING "\r\nRING\r\n"
72 #define HSP_MICROPHONE_GAIN "+VGM"
73 #define HSP_SPEAKER_GAIN "+VGS"
74 
75 #define HSP_HS_MICROPHONE_GAIN "AT+VGM="
76 #define HSP_HS_SPEAKER_GAIN "AT+VGS="
77 
78 static const char default_hsp_ag_service_name[] = "Audio Gateway";
79 
80 static bd_addr_t remote;
81 static bd_addr_t sco_event_addr;
82 static uint8_t channel_nr = 0;
83 
84 static uint16_t mtu;
85 static uint16_t rfcomm_cid = 0;
86 static uint16_t sco_handle = 0;
87 static uint16_t rfcomm_handle = 0;
88 static btstack_timer_source_t hs_timeout;
89 
90 static int ag_microphone_gain = -1;
91 static int ag_speaker_gain = -1;
92 static uint8_t ag_ring = 0;
93 static uint8_t ag_send_ok = 0;
94 static uint8_t ag_send_error = 0;
95 static uint8_t ag_num_button_press_received = 0;
96 static uint8_t ag_support_custom_commands = 0;
97 static uint8_t ag_establish_sco = 0;
98 static uint8_t hsp_disconnect_rfcomm = 0;
99 static uint8_t hsp_establish_audio_connection = 0;
100 static uint8_t hsp_release_audio_connection = 0;
101 
102 static btstack_packet_callback_registration_t hci_event_callback_registration;
103 
104 typedef enum {
105     HSP_IDLE,
106     HSP_SDP_QUERY_RFCOMM_CHANNEL,
107     HSP_W4_SDP_EVENT_QUERY_COMPLETE,
108     HSP_W4_RFCOMM_CONNECTED,
109 
110     HSP_RFCOMM_CONNECTION_ESTABLISHED,
111 
112     HSP_W4_RING_ANSWER,
113     HSP_W4_USER_ACTION,
114     HSP_W2_CONNECT_SCO,
115     HSP_W4_SCO_CONNECTED,
116 
117     HSP_AUDIO_CONNECTION_ESTABLISHED,
118 
119     HSP_W2_DISCONNECT_SCO,
120     HSP_W4_SCO_DISCONNECTED,
121 
122     HSP_W2_DISCONNECT_RFCOMM,
123     HSP_W4_RFCOMM_DISCONNECTED,
124     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
125 } hsp_state_t;
126 
127 static hsp_state_t hsp_state = HSP_IDLE;
128 
129 
130 static btstack_packet_handler_t hsp_ag_callback;
131 
132 static void hsp_run(void);
133 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
134 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
135 
136 static void dummy_notify(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t size){
137     UNUSED(packet_type);
138     UNUSED(channel);
139     UNUSED(event);
140     UNUSED(size);
141 }
142 
143 void hsp_ag_register_packet_handler(btstack_packet_handler_t callback){
144     if (callback == NULL){
145         callback = &dummy_notify;
146     }
147     hsp_ag_callback = callback;
148 }
149 
150 static void emit_event(uint8_t event_subtype, uint8_t value){
151     if (!hsp_ag_callback) return;
152     uint8_t event[4];
153     event[0] = HCI_EVENT_HSP_META;
154     event[1] = sizeof(event) - 2;
155     event[2] = event_subtype;
156     event[3] = value; // status 0 == OK
157     (*hsp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
158 }
159 
160 static void emit_event_audio_connected(uint8_t status, uint16_t handle){
161     if (!hsp_ag_callback) return;
162     uint8_t event[6];
163     event[0] = HCI_EVENT_HSP_META;
164     event[1] = sizeof(event) - 2;
165     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
166     event[3] = status;
167     little_endian_store_16(event, 4, handle);
168     (*hsp_ag_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
169 }
170 
171 void hsp_ag_create_sdp_record(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr, const char * name){
172     uint8_t* attribute;
173     de_create_sequence(service);
174 
175     // 0x0000 "Service Record Handle"
176     de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
177     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
178 
179     // 0x0001 "Service Class ID List"
180     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
181     attribute = de_push_sequence(service);
182     {
183         //  "UUID for PAN Service"
184         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_AG);
185         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio);
186     }
187     de_pop_sequence(service, attribute);
188 
189     // 0x0004 "Protocol Descriptor List"
190     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
191     attribute = de_push_sequence(service);
192     {
193         uint8_t* l2cpProtocol = de_push_sequence(attribute);
194         {
195             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
196         }
197         de_pop_sequence(attribute, l2cpProtocol);
198 
199         uint8_t* rfcomm = de_push_sequence(attribute);
200         {
201             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol);  // rfcomm_service
202             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
203         }
204         de_pop_sequence(attribute, rfcomm);
205     }
206     de_pop_sequence(service, attribute);
207 
208     // 0x0005 "Public Browse Group"
209     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
210     attribute = de_push_sequence(service);
211     {
212         de_add_number(attribute,  DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
213     }
214     de_pop_sequence(service, attribute);
215 
216     // 0x0009 "Bluetooth Profile Descriptor List"
217     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
218     attribute = de_push_sequence(service);
219     {
220         uint8_t *sppProfile = de_push_sequence(attribute);
221         {
222             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, SDP_HSP);
223             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
224         }
225         de_pop_sequence(attribute, sppProfile);
226     }
227     de_pop_sequence(service, attribute);
228 
229     // 0x0100 "Service Name"
230     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
231     if (name){
232         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
233     } else {
234         de_add_data(service,  DE_STRING, strlen(default_hsp_ag_service_name), (uint8_t *) default_hsp_ag_service_name);
235     }
236 }
237 
238 static int hsp_ag_send_str_over_rfcomm(const uint16_t cid, char * command){
239     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
240     if (err){
241         log_error("rfcomm_send_internal -> error 0X%02x", err);
242         return err;
243     }
244     return err;
245 }
246 
247 void hsp_ag_enable_custom_commands(int enable){
248     ag_support_custom_commands = enable;
249 }
250 
251 int hsp_ag_send_result(char * result){
252     if (!ag_support_custom_commands) return 1;
253     return hsp_ag_send_str_over_rfcomm(rfcomm_cid, result);
254 }
255 
256 static void hsp_ag_reset_state(void){
257     hsp_state = HSP_IDLE;
258 
259     rfcomm_cid = 0;
260     rfcomm_handle = 0;
261     sco_handle = 0;
262 
263     ag_send_ok = 0;
264     ag_send_error = 0;
265     ag_ring = 0;
266 
267     ag_num_button_press_received = 0;
268     ag_support_custom_commands = 0;
269 
270     ag_microphone_gain = -1;
271     ag_speaker_gain = -1;
272 
273     hsp_disconnect_rfcomm = 0;
274     hsp_establish_audio_connection = 0;
275     hsp_release_audio_connection = 0;
276 }
277 
278 void hsp_ag_init(uint8_t rfcomm_channel_nr){
279     // register for HCI events
280     hci_event_callback_registration.callback = &packet_handler;
281     hci_add_event_handler(&hci_event_callback_registration);
282 
283     rfcomm_register_service(packet_handler, rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
284 
285     hsp_ag_reset_state();
286 }
287 
288 void hsp_ag_connect(bd_addr_t bd_addr){
289     if (hsp_state != HSP_IDLE) return;
290     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
291     memcpy(remote, bd_addr, 6);
292     hsp_run();
293 }
294 
295 void hsp_ag_disconnect(void){
296     hsp_ag_release_audio_connection();
297     if (hsp_state < HSP_W4_RFCOMM_CONNECTED){
298         hsp_state = HSP_IDLE;
299         return;
300     }
301 
302     if (hsp_state == HSP_W4_RFCOMM_CONNECTED){
303         hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
304         return;
305     }
306     hsp_disconnect_rfcomm = 1;
307     hsp_run();
308 }
309 
310 void hsp_ag_establish_audio_connection(void){
311     switch (hsp_state){
312         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
313             hsp_establish_audio_connection = 1;
314             hsp_state = HSP_W4_SCO_CONNECTED;
315             break;
316         case HSP_W4_RFCOMM_CONNECTED:
317             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
318             break;
319         default:
320             break;
321     }
322     hsp_run();
323 }
324 
325 void hsp_ag_release_audio_connection(void){
326     if (hsp_state >= HSP_W2_DISCONNECT_SCO) return;
327     if (hsp_state < HSP_AUDIO_CONNECTION_ESTABLISHED) return;
328 
329     hsp_release_audio_connection = 1;
330     hsp_run();
331 }
332 
333 
334 void hsp_ag_set_microphone_gain(uint8_t gain){
335     if (gain < 0 || gain >15) {
336         log_error("Gain must be in interval [0..15], it is given %d", gain);
337         return;
338     }
339     ag_microphone_gain = gain;
340     hsp_run();
341 }
342 
343 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
344 void hsp_ag_set_speaker_gain(uint8_t gain){
345     if (gain < 0 || gain >15) {
346         log_error("Gain must be in interval [0..15], it is given %d", gain);
347         return;
348     }
349     ag_speaker_gain = gain;
350     hsp_run();
351 }
352 
353 static void hsp_ringing_timeout_handler(btstack_timer_source_t * timer){
354     UNUSED(timer);
355 
356     ag_ring = 1;
357     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
358     btstack_run_loop_add_timer(&hs_timeout);
359     hsp_run();
360 }
361 
362 static void hsp_ringing_timer_start(void){
363     btstack_run_loop_remove_timer(&hs_timeout);
364     btstack_run_loop_set_timer_handler(&hs_timeout, hsp_ringing_timeout_handler);
365     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
366     btstack_run_loop_add_timer(&hs_timeout);
367 }
368 
369 static void hsp_ringing_timer_stop(void){
370     btstack_run_loop_remove_timer(&hs_timeout);
371 }
372 
373 void hsp_ag_start_ringing(void){
374     ag_ring = 1;
375     if (hsp_state == HSP_W2_CONNECT_SCO) {
376         hsp_state = HSP_W4_RING_ANSWER;
377     }
378     hsp_ringing_timer_start();
379 }
380 
381 void hsp_ag_stop_ringing(void){
382     ag_ring = 0;
383     if (hsp_state == HSP_W4_RING_ANSWER){
384         hsp_state = HSP_W2_CONNECT_SCO;
385     }
386     hsp_ringing_timer_stop();
387 }
388 
389 static void hsp_run(void){
390     if (ag_establish_sco && hci_can_send_command_packet_now()){
391         ag_establish_sco = 0;
392 
393         log_info("HSP: sending hci_accept_connection_request.");
394         // remote supported feature eSCO is set if link type is eSCO
395         // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
396         uint16_t max_latency;
397         uint8_t  retransmission_effort;
398         uint16_t packet_types;
399 
400         if (hci_remote_esco_supported(rfcomm_handle)){
401             max_latency = 0x000c;
402             retransmission_effort = 0x02;
403             packet_types = 0x388;
404         } else {
405             max_latency = 0xffff;
406             retransmission_effort = 0xff;
407             packet_types = 0x003f;
408         }
409 
410         uint16_t sco_voice_setting = hci_get_sco_voice_setting();
411 
412         log_info("HFP: sending hci_accept_connection_request, sco_voice_setting %02x", sco_voice_setting);
413         hci_send_cmd(&hci_accept_synchronous_connection, remote, 8000, 8000, max_latency,
414                         sco_voice_setting, retransmission_effort, packet_types);
415         return;
416     }
417 
418     if (ag_send_ok){
419         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
420             rfcomm_request_can_send_now_event(rfcomm_cid);
421             return;
422         }
423         ag_send_ok = 0;
424         hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
425         return;
426     }
427 
428     if (ag_send_error){
429         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
430             rfcomm_request_can_send_now_event(rfcomm_cid);
431             return;
432         }
433         ag_send_error = 0;
434         hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
435         return;
436     }
437 
438     if (ag_ring){
439         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
440             rfcomm_request_can_send_now_event(rfcomm_cid);
441             return;
442         }
443         ag_ring = 0;
444         hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
445         return;
446     }
447 
448     if (hsp_establish_audio_connection){
449         if (!hci_can_send_command_packet_now()) return;
450         hsp_establish_audio_connection = 0;
451         hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
452         return;
453     }
454 
455     if (hsp_release_audio_connection){
456         hsp_release_audio_connection = 0;
457         gap_disconnect(sco_handle);
458         return;
459     }
460 
461     if (hsp_disconnect_rfcomm){
462         hsp_disconnect_rfcomm = 0;
463         hsp_establish_audio_connection = 0;
464         rfcomm_disconnect(rfcomm_cid);
465         return;
466     }
467 
468     switch (hsp_state){
469         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
470             hsp_state = HSP_W4_SDP_EVENT_QUERY_COMPLETE;
471             log_info("Start SDP query %s, 0x%02x", bd_addr_to_str(remote), SDP_HSP);
472             sdp_client_query_rfcomm_channel_and_name_for_uuid(&handle_query_rfcomm_event, remote, SDP_HSP);
473             break;
474 
475         case HSP_W4_RING_ANSWER:
476             if (!ag_num_button_press_received) break;
477 
478             if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
479                 rfcomm_request_can_send_now_event(rfcomm_cid);
480                 return;
481             }
482 
483             ag_send_ok = 0;
484             ag_num_button_press_received = 0;
485             hsp_state = HSP_W2_CONNECT_SCO;
486 
487             hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
488             break;
489 
490         case HSP_W2_CONNECT_SCO:
491             if (!hci_can_send_command_packet_now()) return;
492             hsp_state = HSP_W4_SCO_CONNECTED;
493             hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
494             break;
495 
496         case HSP_W2_DISCONNECT_SCO:
497             ag_num_button_press_received = 0;
498 
499             hsp_state = HSP_W4_SCO_DISCONNECTED;
500             gap_disconnect(sco_handle);
501             break;
502 
503         case HSP_W2_DISCONNECT_RFCOMM:
504             rfcomm_disconnect(rfcomm_cid);
505             break;
506 
507         case HSP_AUDIO_CONNECTION_ESTABLISHED:
508         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
509 
510             if (ag_microphone_gain >= 0){
511                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
512                     rfcomm_request_can_send_now_event(rfcomm_cid);
513                     return;
514                 }
515                 int gain = ag_microphone_gain;
516                 ag_microphone_gain = -1;
517                 char buffer[10];
518                 sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, gain);
519                 hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
520                 break;
521             }
522 
523             if (ag_speaker_gain >= 0){
524                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
525                     rfcomm_request_can_send_now_event(rfcomm_cid);
526                     return;
527                 }
528                 int gain = ag_speaker_gain;
529                 ag_speaker_gain = -1;
530                 char buffer[10];
531                 sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, gain);
532                 hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
533                 break;
534             }
535             break;
536         default:
537             break;
538     }
539 }
540 
541 
542 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
543     UNUSED(channel);
544 
545     if (packet_type == RFCOMM_DATA_PACKET){
546         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
547             size--;
548             packet++;
549         }
550 
551         if (strncmp((char *)packet, HSP_HS_BUTTON_PRESS, strlen(HSP_HS_BUTTON_PRESS)) == 0){
552             log_info("Received button press %s", HSP_HS_BUTTON_PRESS);
553             ag_send_ok = 1;
554             switch (hsp_state){
555                 case HSP_AUDIO_CONNECTION_ESTABLISHED:
556                     hsp_release_audio_connection = 1;
557                     break;
558                 case HSP_RFCOMM_CONNECTION_ESTABLISHED:
559                     hsp_establish_audio_connection = 1;
560                     break;
561                 default:
562                     break;
563             }
564         } else if (strncmp((char *)packet, HSP_HS_MICROPHONE_GAIN, strlen(HSP_HS_MICROPHONE_GAIN)) == 0){
565             uint8_t gain = (uint8_t)btstack_atoi((char*)&packet[strlen(HSP_HS_MICROPHONE_GAIN)]);
566             ag_send_ok = 1;
567             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
568 
569         } else if (strncmp((char *)packet, HSP_HS_SPEAKER_GAIN, strlen(HSP_HS_SPEAKER_GAIN)) == 0){
570             uint8_t gain = (uint8_t)btstack_atoi((char*)&packet[strlen(HSP_HS_SPEAKER_GAIN)]);
571             ag_send_ok = 1;
572             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
573 
574         } else if (strncmp((char *)packet, "AT+", 3) == 0){
575             ag_send_error = 1;
576             if (!hsp_ag_callback) return;
577             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
578             uint8_t * event = packet - 4;
579             event[0] = HCI_EVENT_HSP_META;
580             event[1] = size + 2;
581             event[2] = HSP_SUBEVENT_HS_COMMAND;
582             event[3] = size;
583             (*hsp_ag_callback)(HCI_EVENT_PACKET, 0, event, size+4);
584         }
585 
586         hsp_run();
587         return;
588     }
589 
590     if (packet_type != HCI_EVENT_PACKET) return;
591     uint8_t event = hci_event_packet_get_type(packet);
592     bd_addr_t event_addr;
593     uint16_t handle;
594 
595     switch (event) {
596         case HCI_EVENT_CONNECTION_REQUEST:
597             hci_event_connection_request_get_bd_addr(packet, sco_event_addr);
598             ag_establish_sco = 1;
599             break;
600         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
601             uint8_t status = hci_event_synchronous_connection_complete_get_status(packet);
602             if (status != 0){
603                 log_error("(e)SCO Connection failed, status %u", status);
604                 emit_event_audio_connected(status, sco_handle);
605                 break;
606             }
607 
608             hci_event_synchronous_connection_complete_get_bd_addr(packet, event_addr);
609             sco_handle = hci_event_synchronous_connection_complete_get_handle(packet);
610             uint8_t  link_type = hci_event_synchronous_connection_complete_get_link_type(packet);
611             uint8_t  transmission_interval = hci_event_synchronous_connection_complete_get_transmission_interval(packet);  // measured in slots
612             uint8_t  retransmission_interval = hci_event_synchronous_connection_complete_get_retransmission_interval(packet);// measured in slots
613             uint16_t rx_packet_length = hci_event_synchronous_connection_complete_get_rx_packet_length(packet); // measured in bytes
614             uint16_t tx_packet_length = hci_event_synchronous_connection_complete_get_tx_packet_length(packet); // measured in bytes
615             uint8_t  air_mode = hci_event_synchronous_connection_complete_get_air_mode(packet);
616 
617             switch (link_type){
618                 case 0x00:
619                     log_info("SCO Connection established.");
620                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
621                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
622                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
623                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
624                     break;
625                 case 0x02:
626                     log_info("eSCO Connection established.");
627                     break;
628                 default:
629                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
630                     break;
631             }
632             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
633                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
634                  bd_addr_to_str(event_addr), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
635 
636             if (hsp_state == HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
637                 hsp_state = HSP_W2_DISCONNECT_SCO;
638                 break;
639             }
640 
641             hsp_state = HSP_AUDIO_CONNECTION_ESTABLISHED;
642             emit_event_audio_connected(status, sco_handle);
643             break;
644         }
645 
646         case RFCOMM_EVENT_INCOMING_CONNECTION:
647             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
648             if (hsp_state != HSP_IDLE) return;
649 
650             rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr);
651             rfcomm_cid = rfcomm_event_incoming_connection_get_server_channel(packet);
652             log_info("RFCOMM channel %u requested for %s", packet[8], bd_addr_to_str(event_addr));
653             hsp_state = HSP_W4_RFCOMM_CONNECTED;
654             rfcomm_accept_connection(rfcomm_cid);
655             break;
656 
657         case RFCOMM_EVENT_CHANNEL_OPENED:
658             log_info("RFCOMM_EVENT_CHANNEL_OPENED packet_handler type %u, packet[0] %x", packet_type, packet[0]);
659             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
660             if (rfcomm_event_channel_opened_get_status(packet)) {
661                 log_info("RFCOMM channel open failed, status %u§", rfcomm_event_channel_opened_get_status(packet));
662                 hsp_ag_reset_state();
663                 hsp_state = HSP_IDLE;
664             } else {
665                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
666                 rfcomm_handle = rfcomm_event_channel_opened_get_con_handle(packet);
667                 rfcomm_cid = rfcomm_event_channel_opened_get_rfcomm_cid(packet);
668                 mtu = rfcomm_event_channel_opened_get_max_frame_size(packet);
669                 log_info("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, state %d", rfcomm_cid, mtu, hsp_state);
670                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
671             }
672             emit_event(HSP_SUBEVENT_RFCOMM_CONNECTION_COMPLETE, packet[2]);
673             break;
674 
675         case RFCOMM_EVENT_CHANNEL_CLOSED:
676             rfcomm_handle = 0;
677             hsp_state = HSP_IDLE;
678             hsp_ag_reset_state();
679             emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE,0);
680             break;
681 
682         case RFCOMM_EVENT_CAN_SEND_NOW:
683             hsp_run();
684             break;
685 
686         case HCI_EVENT_DISCONNECTION_COMPLETE:
687             handle = little_endian_read_16(packet,3);
688             if (handle == sco_handle){
689                 sco_handle = 0;
690                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
691                 emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
692                 break;
693             }
694             if (handle == rfcomm_handle) {
695                 rfcomm_handle = 0;
696                 hsp_state = HSP_IDLE;
697                 hsp_ag_reset_state();
698                 emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE,0);
699             }
700             break;
701 
702         default:
703             break;
704     }
705 
706     hsp_run();
707 }
708 
709 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
710     UNUSED(packet_type);
711     UNUSED(channel);
712     UNUSED(size);
713 
714     switch (packet[0]){
715         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
716             channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
717             log_info("** Service name: '%s', RFCOMM port %u", sdp_event_query_rfcomm_service_get_name(packet), channel_nr);
718             break;
719         case SDP_EVENT_QUERY_COMPLETE:
720             if (channel_nr > 0){
721                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
722                 log_info("RFCOMM create channel. state %d", HSP_W4_RFCOMM_CONNECTED);
723                 rfcomm_create_channel(packet_handler, remote, channel_nr, NULL);
724                 break;
725             }
726             hsp_ag_reset_state();
727             log_info("Service not found, status %u.\n", sdp_event_query_complete_get_status(packet));
728             if (sdp_event_query_complete_get_status(packet)){
729                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, sdp_event_query_complete_get_status(packet));
730             } else {
731                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
732             }
733             break;
734         default:
735             break;
736     }
737 }
738 
739 
740