xref: /btstack/src/classic/hsp_ag.c (revision f8fbdce0c5067e7e7edd3a29934b1f9b79c8ff2d)
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 // Minimal setup for HSP Audio Gateway (!! UNDER DEVELOPMENT !!)
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/sdp.h"
56 #include "classic/sdp_query_rfcomm.h"
57 #include "hci.h"
58 #include "hci_cmd.h"
59 #include "hci_dump.h"
60 #include "hsp_ag.h"
61 #include "l2cap.h"
62 
63 #define RFCOMM_SERVER_CHANNEL 1
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 uint8_t channel_nr = 0;
80 
81 static uint16_t mtu;
82 static uint16_t rfcomm_cid = 0;
83 static uint16_t sco_handle = 0;
84 static uint16_t rfcomm_handle = 0;
85 static btstack_timer_source_t hs_timeout;
86 
87 // static uint8_t connection_state = 0;
88 
89 static int ag_microphone_gain = -1;
90 static int ag_speaker_gain = -1;
91 static uint8_t ag_ring = 0;
92 static uint8_t ag_send_ok = 0;
93 static uint8_t ag_send_error = 0;
94 static uint8_t ag_num_button_press_received = 0;
95 static uint8_t ag_support_custom_commands = 0;
96 
97 typedef enum {
98     HSP_IDLE,
99     HSP_SDP_QUERY_RFCOMM_CHANNEL,
100     HSP_W4_SDP_EVENT_QUERY_COMPLETE,
101     HSP_W4_RFCOMM_CONNECTED,
102     HSP_W4_RING_ANSWER,
103     HSP_W4_USER_ACTION,
104     HSP_W2_CONNECT_SCO,
105     HSP_W4_SCO_CONNECTED,
106     HSP_ACTIVE,
107     HSP_W2_DISCONNECT_SCO,
108     HSP_W4_SCO_DISCONNECTED,
109     HSP_W2_DISCONNECT_RFCOMM,
110     HSP_W4_RFCOMM_DISCONNECTED,
111     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
112 } hsp_state_t;
113 
114 static hsp_state_t hsp_state = HSP_IDLE;
115 
116 
117 static hsp_ag_callback_t hsp_ag_callback;
118 
119 static void hsp_run();
120 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
121 static void handle_query_rfcomm_event(uint8_t packet_type, uint8_t *packet, uint16_t size, void * context);
122 
123 static void dummy_notify(uint8_t * event, uint16_t size){}
124 
125 void hsp_ag_register_packet_handler(hsp_ag_callback_t callback){
126     if (callback == NULL){
127         callback = &dummy_notify;
128     }
129     hsp_ag_callback = callback;
130 }
131 
132 static void emit_event(uint8_t event_subtype, uint8_t value){
133     if (!hsp_ag_callback) return;
134     uint8_t event[4];
135     event[0] = HCI_EVENT_HSP_META;
136     event[1] = sizeof(event) - 2;
137     event[2] = event_subtype;
138     event[3] = value; // status 0 == OK
139     (*hsp_ag_callback)(event, sizeof(event));
140 }
141 
142 static void emit_event_audio_connected(uint8_t status, uint16_t handle){
143     if (!hsp_hs_callback) return;
144     uint8_t event[6];
145     event[0] = HCI_EVENT_HSP_META;
146     event[1] = sizeof(event) - 2;
147     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
148     event[3] = status;
149     little_endian_store_16(event, 4, handle);
150     (*hsp_hs_callback)(event, sizeof(event));
151 }
152 
153 void hsp_ag_create_service(uint8_t * service, int rfcomm_channel_nr, const char * name){
154     uint8_t* attribute;
155     de_create_sequence(service);
156 
157     // 0x0000 "Service Record Handle"
158     de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
159     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
160 
161     // 0x0001 "Service Class ID List"
162     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
163     attribute = de_push_sequence(service);
164     {
165         //  "UUID for PAN Service"
166         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_AG);
167         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio);
168     }
169     de_pop_sequence(service, attribute);
170 
171     // 0x0004 "Protocol Descriptor List"
172     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
173     attribute = de_push_sequence(service);
174     {
175         uint8_t* l2cpProtocol = de_push_sequence(attribute);
176         {
177             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
178         }
179         de_pop_sequence(attribute, l2cpProtocol);
180 
181         uint8_t* rfcomm = de_push_sequence(attribute);
182         {
183             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol);  // rfcomm_service
184             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
185         }
186         de_pop_sequence(attribute, rfcomm);
187     }
188     de_pop_sequence(service, attribute);
189 
190     // 0x0005 "Public Browse Group"
191     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
192     attribute = de_push_sequence(service);
193     {
194         de_add_number(attribute,  DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
195     }
196     de_pop_sequence(service, attribute);
197 
198     // 0x0009 "Bluetooth Profile Descriptor List"
199     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
200     attribute = de_push_sequence(service);
201     {
202         uint8_t *sppProfile = de_push_sequence(attribute);
203         {
204             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, SDP_HSP);
205             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
206         }
207         de_pop_sequence(attribute, sppProfile);
208     }
209     de_pop_sequence(service, attribute);
210 
211     // 0x0100 "Service Name"
212     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
213     if (name){
214         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
215     } else {
216         de_add_data(service,  DE_STRING, strlen(default_hsp_ag_service_name), (uint8_t *) default_hsp_ag_service_name);
217     }
218 }
219 
220 static int hsp_ag_send_str_over_rfcomm(uint16_t cid, char * command){
221     if (!rfcomm_can_send_packet_now(cid)) return 1;
222     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
223     if (err){
224         printf("rfcomm_send -> error 0X%02x", err);
225         return err;
226     }
227     printf("Send string: \"%s\"\n", command);
228     return err;
229 }
230 
231 void hsp_ag_support_custom_commands(int enable){
232     ag_support_custom_commands = enable;
233 }
234 
235 int hsp_ag_send_result(char * result){
236     if (!ag_support_custom_commands) return 1;
237     return hsp_ag_send_str_over_rfcomm(rfcomm_cid, result);
238 }
239 
240 
241 static void hsp_ag_reset_state(void){
242     hsp_state = HSP_IDLE;
243 
244     rfcomm_cid = 0;
245     rfcomm_handle = 0;
246     sco_handle = 0;
247 
248     ag_send_ok = 0;
249     ag_send_error = 0;
250     ag_ring = 0;
251 
252     ag_num_button_press_received = 0;
253     ag_support_custom_commands = 0;
254 
255     ag_microphone_gain = -1;
256     ag_speaker_gain = -1;
257 }
258 
259 void hsp_ag_init(uint8_t rfcomm_channel_nr){
260     // init L2CAP
261     l2cap_init();
262     l2cap_register_packet_handler(packet_handler);
263 
264     rfcomm_init();
265     rfcomm_register_packet_handler(packet_handler);
266     rfcomm_register_service(rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
267 
268     sdp_query_rfcomm_register_callback(handle_query_rfcomm_event, NULL);
269 
270     hsp_ag_reset_state();
271 }
272 
273 void hsp_ag_connect(bd_addr_t bd_addr){
274     if (hsp_state != HSP_IDLE) return;
275     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
276     memcpy(remote, bd_addr, 6);
277     hsp_run();
278 }
279 
280 void hsp_ag_disconnect(void){
281     switch (hsp_state){
282         case HSP_ACTIVE:
283             hsp_state = HSP_W2_DISCONNECT_SCO;
284             break;
285         case HSP_W2_CONNECT_SCO:
286             hsp_state = HSP_W2_DISCONNECT_RFCOMM;
287             break;
288 
289         case HSP_W4_RFCOMM_CONNECTED:
290         case HSP_W4_SCO_CONNECTED:
291             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
292             break;
293         default:
294             return;
295     }
296     hsp_run();
297 }
298 
299 void hsp_ag_set_microphone_gain(uint8_t gain){
300     if (gain < 0 || gain >15) {
301         printf("Gain must be in interval [0..15], it is given %d\n", gain);
302         return;
303     }
304     ag_microphone_gain = gain;
305     hsp_run();
306 }
307 
308 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
309 void hsp_ag_set_speaker_gain(uint8_t gain){
310     if (gain < 0 || gain >15) {
311         printf("Gain must be in interval [0..15], it is given %d\n", gain);
312         return;
313     }
314     ag_speaker_gain = gain;
315     hsp_run();
316 }
317 
318 static void hsp_timeout_handler(btstack_timer_source_t * timer){
319     ag_ring = 1;
320 }
321 
322 static void hsp_timeout_start(void){
323     btstack_run_loop_remove_timer(&hs_timeout);
324     btstack_run_loop_set_timer_handler(&hs_timeout, hsp_timeout_handler);
325     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
326     btstack_run_loop_add_timer(&hs_timeout);
327 }
328 
329 static void hsp_timeout_stop(void){
330     btstack_run_loop_remove_timer(&hs_timeout);
331 }
332 
333 void hsp_ag_start_ringing(void){
334     if (hsp_state != HSP_W2_CONNECT_SCO) return;
335     ag_ring = 1;
336     hsp_state = HSP_W4_RING_ANSWER;
337     hsp_timeout_start();
338 }
339 
340 void hsp_ag_stop_ringing(void){
341     ag_ring = 0;
342     ag_num_button_press_received = 0;
343     hsp_state = HSP_W2_CONNECT_SCO;
344     hsp_timeout_stop();
345 }
346 
347 static void hsp_run(void){
348     int err;
349 
350     if (ag_send_ok){
351         ag_send_ok = 0;
352         err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
353         if (err){
354             ag_send_ok = 1;
355         }
356         return;
357     }
358 
359     if (ag_send_error){
360         ag_send_error = 0;
361         err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
362         if (err) {
363             ag_send_error = 1;
364         }
365         return;
366     }
367 
368     switch (hsp_state){
369         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
370             hsp_state = HSP_W4_SDP_EVENT_QUERY_COMPLETE;
371             printf("Start SDP query %s, 0x%02x\n", bd_addr_to_str(remote), SDP_HSP);
372             sdp_query_rfcomm_channel_and_name_for_uuid(remote, SDP_HSP);
373             break;
374 
375         case HSP_W4_RING_ANSWER:
376             if (ag_ring){
377                 ag_ring = 0;
378                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
379                 if (err) {
380                     ag_ring = 1;
381                 }
382                 break;
383             }
384 
385             if (!ag_num_button_press_received) break;
386             ag_send_ok = 0;
387 
388             ag_num_button_press_received = 0;
389             hsp_state = HSP_W2_CONNECT_SCO;
390 
391             err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
392             if (err) {
393                 hsp_state = HSP_W4_RING_ANSWER;
394                 ag_num_button_press_received = 1;
395             }
396             break;
397         case HSP_W2_CONNECT_SCO:
398             if (!hci_can_send_command_packet_now()) break;
399             hsp_state = HSP_W4_SCO_CONNECTED;
400             hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
401             break;
402 
403         case HSP_W2_DISCONNECT_SCO:
404             ag_num_button_press_received = 0;
405 
406             hsp_state = HSP_W4_SCO_DISCONNECTED;
407             gap_disconnect(sco_handle);
408             break;
409 
410         case HSP_W2_DISCONNECT_RFCOMM:
411             hsp_state = HSP_W4_RFCOMM_DISCONNECTED;
412             rfcomm_disconnect(rfcomm_cid);
413             break;
414         case HSP_ACTIVE:
415 
416             if (ag_microphone_gain >= 0){
417                 int gain = ag_microphone_gain;
418                 ag_microphone_gain = -1;
419                 char buffer[10];
420                 sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, gain);
421                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
422                 if (err) {
423                     ag_microphone_gain = gain;
424                 }
425                 break;
426             }
427 
428             if (ag_speaker_gain >= 0){
429                 int gain = ag_speaker_gain;
430                 ag_speaker_gain = -1;
431                 char buffer[10];
432                 sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, gain);
433                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
434                 if (err) {
435                     ag_speaker_gain = gain;
436                 }
437                 break;
438             }
439             break;
440         default:
441             break;
442     }
443 }
444 
445 
446 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
447     // printf("packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
448     if (packet_type == RFCOMM_DATA_PACKET){
449         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
450             size--;
451             packet++;
452         }
453 
454         if (strncmp((char *)packet, HSP_HS_BUTTON_PRESS, strlen(HSP_HS_BUTTON_PRESS)) == 0){
455             printf("Received button press %s\n", HSP_HS_BUTTON_PRESS);
456             ag_num_button_press_received++;
457             ag_send_ok = 1;
458             if (hsp_state == HSP_ACTIVE && ag_num_button_press_received >=2){
459                 ag_num_button_press_received = 0;
460                 hsp_state = HSP_W2_DISCONNECT_SCO;
461             }
462         } else if (strncmp((char *)packet, HSP_HS_MICROPHONE_GAIN, strlen(HSP_HS_MICROPHONE_GAIN)) == 0){
463             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_MICROPHONE_GAIN)]);
464             ag_send_ok = 1;
465             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
466 
467         } else if (strncmp((char *)packet, HSP_HS_SPEAKER_GAIN, strlen(HSP_HS_SPEAKER_GAIN)) == 0){
468             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_SPEAKER_GAIN)]);
469             ag_send_ok = 1;
470             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
471 
472         } else if (strncmp((char *)packet, "AT+", 3) == 0){
473             ag_send_error = 1;
474             if (!hsp_ag_callback) return;
475             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
476             uint8_t * event = packet - 3;
477             event[0] = HCI_EVENT_HSP_META;
478             event[1] = size + 1;
479             event[2] = HSP_SUBEVENT_HS_COMMAND;
480             (*hsp_ag_callback)(event, size+3);
481         }
482 
483         hsp_run();
484         return;
485     }
486 
487     if (packet_type != HCI_EVENT_PACKET) return;
488     uint8_t event = packet[0];
489     bd_addr_t event_addr;
490     uint16_t handle;
491 
492     switch (event) {
493         case BTSTACK_EVENT_STATE:
494             // BTstack activated, get started
495             if (packet[2] == HCI_STATE_WORKING){
496                 printf("BTstack activated, get started .\n");
497             }
498             break;
499 
500         case HCI_EVENT_PIN_CODE_REQUEST:
501             // inform about pin code request
502             printf("Pin code request - using '0000'\n\r");
503             bt_flip_addr(event_addr, &packet[2]);
504             hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000");
505             break;
506         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
507             int index = 2;
508             uint8_t status = packet[index++];
509             sco_handle = little_endian_read_16(packet, index);
510             index+=2;
511             bd_addr_t address;
512             memcpy(address, &packet[index], 6);
513             index+=6;
514             uint8_t link_type = packet[index++];
515             uint8_t transmission_interval = packet[index++];  // measured in slots
516             uint8_t retransmission_interval = packet[index++];// measured in slots
517             uint16_t rx_packet_length = little_endian_read_16(packet, index); // measured in bytes
518             index+=2;
519             uint16_t tx_packet_length = little_endian_read_16(packet, index); // measured in bytes
520             index+=2;
521             uint8_t air_mode = packet[index];
522 
523             if (status != 0){
524                 log_error("(e)SCO Connection failed, status %u", status);
525                 emit_event_audio_connected(status, sco_handle);
526                 break;
527             }
528             switch (link_type){
529                 case 0x00:
530                     printf("SCO Connection established. \n");
531                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
532                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
533                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
534                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
535                     break;
536                 case 0x02:
537                     printf("eSCO Connection established. \n");
538                     break;
539                 default:
540                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
541                     break;
542             }
543             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
544                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
545                  bd_addr_to_str(address), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
546 
547             if (hsp_state == HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
548                 hsp_state = HSP_W2_DISCONNECT_SCO;
549                 break;
550             }
551 
552             hsp_state = HSP_ACTIVE;
553             emit_event_audio_connected(status, sco_handle);
554             break;
555         }
556 
557         case RFCOMM_EVENT_INCOMING_CONNECTION:
558             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
559             if (hsp_state != HSP_IDLE) return;
560 
561             bt_flip_addr(event_addr, &packet[2]);
562             rfcomm_cid = little_endian_read_16(packet, 9);
563             printf("RFCOMM channel %u requested for %s\n", packet[8], bd_addr_to_str(event_addr));
564             rfcomm_accept_connection(rfcomm_cid);
565 
566             hsp_state = HSP_W4_RFCOMM_CONNECTED;
567 
568             break;
569 
570         case RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE:
571             printf("RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
572             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
573             if (packet[2]) {
574                 printf("RFCOMM channel open failed, status %u\n", packet[2]);
575                 hsp_ag_reset_state();
576                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, packet[2]);
577             } else {
578                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
579                 rfcomm_handle = little_endian_read_16(packet, 9);
580                 rfcomm_cid = little_endian_read_16(packet, 12);
581                 mtu = little_endian_read_16(packet, 14);
582                 printf("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, state %d\n", rfcomm_cid, mtu, hsp_state);
583 
584                 switch (hsp_state){
585                     case HSP_W4_RFCOMM_CONNECTED:
586                         ag_num_button_press_received = 0;
587                         hsp_state = HSP_W2_CONNECT_SCO;
588                         break;
589                     case HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN:
590                         hsp_state = HSP_W2_DISCONNECT_RFCOMM;
591                         break;
592                     default:
593                         printf("no valid state\n");
594                         break;
595                 }
596             }
597             break;
598         case DAEMON_EVENT_HCI_PACKET_SENT:
599         case RFCOMM_EVENT_CREDITS:
600             break;
601 
602         case HCI_EVENT_DISCONNECTION_COMPLETE:
603             if (hsp_state != HSP_W4_SCO_DISCONNECTED){
604                 log_info("received gap disconnect in wrong hsp state");
605             }
606             handle = little_endian_read_16(packet,3);
607             if (handle == sco_handle){
608                 printf("SCO disconnected, w2 disconnect RFCOMM\n");
609                 sco_handle = 0;
610                 hsp_state = HSP_W2_DISCONNECT_RFCOMM;
611                 break;
612             }
613             break;
614         case RFCOMM_EVENT_CHANNEL_CLOSED:
615             if (hsp_state != HSP_W4_RFCOMM_DISCONNECTED){
616                 log_info("received RFCOMM disconnect in wrong hsp state");
617             }
618             printf("RFCOMM channel closed\n");
619             hsp_ag_reset_state();
620             emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
621             break;
622         default:
623             break;
624     }
625     hsp_run();
626 }
627 
628 static void handle_query_rfcomm_event(uint8_t packet_type, uint8_t *packet, uint16_t size, void * context){
629     switch (event->type){
630         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
631             channel_nr = sdp_query_rfcomm_service_event_get_rfcomm_channel(packet);
632             printf("** Service name: '%s', RFCOMM port %u\n", sdp_query_rfcomm_service_event_get_name(packet), channel_nr);
633             break;
634         case SDP_EVENT_QUERY_COMPLETE:
635             if (channel_nr > 0){
636                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
637                 printf("RFCOMM create channel. state %d\n", HSP_W4_RFCOMM_CONNECTED);
638                 rfcomm_create_channel(remote, channel_nr, NULL);
639                 break;
640             }
641             hsp_ag_reset_state();
642             printf("Service not found, status %u.\n", sdp_query_complete_event_get_status(packet));
643             if (sdp_query_complete_event_get_status(packet)){
644                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, sdp_query_complete_event_get_status(packet));
645             } else {
646                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
647             }
648             break;
649         default:
650             break;
651     }
652 }
653 
654 
655