xref: /btstack/src/classic/hsp_ag.c (revision d9a7306a10f9a1b4dcae1f7fca484233f49c6707)
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 static btstack_packet_callback_registration_t hci_event_callback_registration;
98 
99 typedef enum {
100     HSP_IDLE,
101     HSP_SDP_QUERY_RFCOMM_CHANNEL,
102     HSP_W4_SDP_EVENT_QUERY_COMPLETE,
103     HSP_W4_RFCOMM_CONNECTED,
104     HSP_W4_RING_ANSWER,
105     HSP_W4_USER_ACTION,
106     HSP_W2_CONNECT_SCO,
107     HSP_W4_SCO_CONNECTED,
108     HSP_ACTIVE,
109     HSP_W2_DISCONNECT_SCO,
110     HSP_W4_SCO_DISCONNECTED,
111     HSP_W2_DISCONNECT_RFCOMM,
112     HSP_W4_RFCOMM_DISCONNECTED,
113     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
114 } hsp_state_t;
115 
116 static hsp_state_t hsp_state = HSP_IDLE;
117 
118 
119 static hsp_ag_callback_t hsp_ag_callback;
120 
121 static void hsp_run();
122 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
123 static void handle_query_rfcomm_event(uint8_t packet_type, uint8_t *packet, uint16_t size);
124 
125 static void dummy_notify(uint8_t * event, uint16_t size){}
126 
127 void hsp_ag_register_packet_handler(hsp_ag_callback_t callback){
128     if (callback == NULL){
129         callback = &dummy_notify;
130     }
131     hsp_ag_callback = callback;
132 }
133 
134 static void emit_event(uint8_t event_subtype, uint8_t value){
135     if (!hsp_ag_callback) return;
136     uint8_t event[4];
137     event[0] = HCI_EVENT_HSP_META;
138     event[1] = sizeof(event) - 2;
139     event[2] = event_subtype;
140     event[3] = value; // status 0 == OK
141     (*hsp_ag_callback)(event, sizeof(event));
142 }
143 
144 static void emit_event_audio_connected(uint8_t status, uint16_t handle){
145     if (!hsp_ag_callback) return;
146     uint8_t event[6];
147     event[0] = HCI_EVENT_HSP_META;
148     event[1] = sizeof(event) - 2;
149     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
150     event[3] = status;
151     little_endian_store_16(event, 4, handle);
152     (*hsp_ag_callback)(event, sizeof(event));
153 }
154 
155 void hsp_ag_create_service(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr, const char * name){
156     uint8_t* attribute;
157     de_create_sequence(service);
158 
159     // 0x0000 "Service Record Handle"
160     de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
161     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
162 
163     // 0x0001 "Service Class ID List"
164     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
165     attribute = de_push_sequence(service);
166     {
167         //  "UUID for PAN Service"
168         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_AG);
169         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio);
170     }
171     de_pop_sequence(service, attribute);
172 
173     // 0x0004 "Protocol Descriptor List"
174     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
175     attribute = de_push_sequence(service);
176     {
177         uint8_t* l2cpProtocol = de_push_sequence(attribute);
178         {
179             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
180         }
181         de_pop_sequence(attribute, l2cpProtocol);
182 
183         uint8_t* rfcomm = de_push_sequence(attribute);
184         {
185             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol);  // rfcomm_service
186             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
187         }
188         de_pop_sequence(attribute, rfcomm);
189     }
190     de_pop_sequence(service, attribute);
191 
192     // 0x0005 "Public Browse Group"
193     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
194     attribute = de_push_sequence(service);
195     {
196         de_add_number(attribute,  DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
197     }
198     de_pop_sequence(service, attribute);
199 
200     // 0x0009 "Bluetooth Profile Descriptor List"
201     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
202     attribute = de_push_sequence(service);
203     {
204         uint8_t *sppProfile = de_push_sequence(attribute);
205         {
206             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, SDP_HSP);
207             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
208         }
209         de_pop_sequence(attribute, sppProfile);
210     }
211     de_pop_sequence(service, attribute);
212 
213     // 0x0100 "Service Name"
214     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
215     if (name){
216         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
217     } else {
218         de_add_data(service,  DE_STRING, strlen(default_hsp_ag_service_name), (uint8_t *) default_hsp_ag_service_name);
219     }
220 }
221 
222 static int hsp_ag_send_str_over_rfcomm(uint16_t cid, char * command){
223     if (!rfcomm_can_send_packet_now(cid)) return 1;
224     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
225     if (err){
226         printf("rfcomm_send -> error 0X%02x", err);
227         return err;
228     }
229     printf("Send string: \"%s\"\n", command);
230     return err;
231 }
232 
233 void hsp_ag_support_custom_commands(int enable){
234     ag_support_custom_commands = enable;
235 }
236 
237 int hsp_ag_send_result(char * result){
238     if (!ag_support_custom_commands) return 1;
239     return hsp_ag_send_str_over_rfcomm(rfcomm_cid, result);
240 }
241 
242 static void hsp_ag_reset_state(void){
243     hsp_state = HSP_IDLE;
244 
245     rfcomm_cid = 0;
246     rfcomm_handle = 0;
247     sco_handle = 0;
248 
249     ag_send_ok = 0;
250     ag_send_error = 0;
251     ag_ring = 0;
252 
253     ag_num_button_press_received = 0;
254     ag_support_custom_commands = 0;
255 
256     ag_microphone_gain = -1;
257     ag_speaker_gain = -1;
258 }
259 
260 void hsp_ag_init(uint8_t rfcomm_channel_nr){
261     // register for HCI events
262     hci_event_callback_registration.callback = &packet_handler;
263     hci_add_event_handler(&hci_event_callback_registration);
264 
265     // init L2CAP
266     l2cap_init();
267 
268     rfcomm_init();
269     rfcomm_register_packet_handler(packet_handler);
270     rfcomm_register_service(rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
271 
272     sdp_query_rfcomm_register_callback(handle_query_rfcomm_event);
273 
274     hsp_ag_reset_state();
275 }
276 
277 void hsp_ag_connect(bd_addr_t bd_addr){
278     if (hsp_state != HSP_IDLE) return;
279     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
280     memcpy(remote, bd_addr, 6);
281     hsp_run();
282 }
283 
284 void hsp_ag_disconnect(void){
285     switch (hsp_state){
286         case HSP_ACTIVE:
287             hsp_state = HSP_W2_DISCONNECT_SCO;
288             break;
289         case HSP_W2_CONNECT_SCO:
290             hsp_state = HSP_W2_DISCONNECT_RFCOMM;
291             break;
292 
293         case HSP_W4_RFCOMM_CONNECTED:
294         case HSP_W4_SCO_CONNECTED:
295             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
296             break;
297         default:
298             return;
299     }
300     hsp_run();
301 }
302 
303 void hsp_ag_set_microphone_gain(uint8_t gain){
304     if (gain < 0 || gain >15) {
305         printf("Gain must be in interval [0..15], it is given %d\n", gain);
306         return;
307     }
308     ag_microphone_gain = gain;
309     hsp_run();
310 }
311 
312 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
313 void hsp_ag_set_speaker_gain(uint8_t gain){
314     if (gain < 0 || gain >15) {
315         printf("Gain must be in interval [0..15], it is given %d\n", gain);
316         return;
317     }
318     ag_speaker_gain = gain;
319     hsp_run();
320 }
321 
322 static void hsp_timeout_handler(btstack_timer_source_t * timer){
323     ag_ring = 1;
324 }
325 
326 static void hsp_timeout_start(void){
327     btstack_run_loop_remove_timer(&hs_timeout);
328     btstack_run_loop_set_timer_handler(&hs_timeout, hsp_timeout_handler);
329     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
330     btstack_run_loop_add_timer(&hs_timeout);
331 }
332 
333 static void hsp_timeout_stop(void){
334     btstack_run_loop_remove_timer(&hs_timeout);
335 }
336 
337 void hsp_ag_start_ringing(void){
338     if (hsp_state != HSP_W2_CONNECT_SCO) return;
339     ag_ring = 1;
340     hsp_state = HSP_W4_RING_ANSWER;
341     hsp_timeout_start();
342 }
343 
344 void hsp_ag_stop_ringing(void){
345     ag_ring = 0;
346     ag_num_button_press_received = 0;
347     hsp_state = HSP_W2_CONNECT_SCO;
348     hsp_timeout_stop();
349 }
350 
351 static void hsp_run(void){
352     int err;
353 
354     if (ag_send_ok){
355         ag_send_ok = 0;
356         err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
357         if (err){
358             ag_send_ok = 1;
359         }
360         return;
361     }
362 
363     if (ag_send_error){
364         ag_send_error = 0;
365         err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
366         if (err) {
367             ag_send_error = 1;
368         }
369         return;
370     }
371 
372     switch (hsp_state){
373         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
374             hsp_state = HSP_W4_SDP_EVENT_QUERY_COMPLETE;
375             printf("Start SDP query %s, 0x%02x\n", bd_addr_to_str(remote), SDP_HSP);
376             sdp_query_rfcomm_channel_and_name_for_uuid(remote, SDP_HSP);
377             break;
378 
379         case HSP_W4_RING_ANSWER:
380             if (ag_ring){
381                 ag_ring = 0;
382                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
383                 if (err) {
384                     ag_ring = 1;
385                 }
386                 break;
387             }
388 
389             if (!ag_num_button_press_received) break;
390             ag_send_ok = 0;
391 
392             ag_num_button_press_received = 0;
393             hsp_state = HSP_W2_CONNECT_SCO;
394 
395             err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
396             if (err) {
397                 hsp_state = HSP_W4_RING_ANSWER;
398                 ag_num_button_press_received = 1;
399             }
400             break;
401         case HSP_W2_CONNECT_SCO:
402             if (!hci_can_send_command_packet_now()) break;
403             hsp_state = HSP_W4_SCO_CONNECTED;
404             hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
405             break;
406 
407         case HSP_W2_DISCONNECT_SCO:
408             ag_num_button_press_received = 0;
409 
410             hsp_state = HSP_W4_SCO_DISCONNECTED;
411             gap_disconnect(sco_handle);
412             break;
413 
414         case HSP_W2_DISCONNECT_RFCOMM:
415             hsp_state = HSP_W4_RFCOMM_DISCONNECTED;
416             rfcomm_disconnect(rfcomm_cid);
417             break;
418         case HSP_ACTIVE:
419 
420             if (ag_microphone_gain >= 0){
421                 int gain = ag_microphone_gain;
422                 ag_microphone_gain = -1;
423                 char buffer[10];
424                 sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, gain);
425                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
426                 if (err) {
427                     ag_microphone_gain = gain;
428                 }
429                 break;
430             }
431 
432             if (ag_speaker_gain >= 0){
433                 int gain = ag_speaker_gain;
434                 ag_speaker_gain = -1;
435                 char buffer[10];
436                 sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, gain);
437                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
438                 if (err) {
439                     ag_speaker_gain = gain;
440                 }
441                 break;
442             }
443             break;
444         default:
445             break;
446     }
447 }
448 
449 
450 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
451     // printf("packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
452     if (packet_type == RFCOMM_DATA_PACKET){
453         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
454             size--;
455             packet++;
456         }
457 
458         if (strncmp((char *)packet, HSP_HS_BUTTON_PRESS, strlen(HSP_HS_BUTTON_PRESS)) == 0){
459             printf("Received button press %s\n", HSP_HS_BUTTON_PRESS);
460             ag_num_button_press_received++;
461             ag_send_ok = 1;
462             if (hsp_state == HSP_ACTIVE && ag_num_button_press_received >=2){
463                 ag_num_button_press_received = 0;
464                 hsp_state = HSP_W2_DISCONNECT_SCO;
465             }
466         } else if (strncmp((char *)packet, HSP_HS_MICROPHONE_GAIN, strlen(HSP_HS_MICROPHONE_GAIN)) == 0){
467             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_MICROPHONE_GAIN)]);
468             ag_send_ok = 1;
469             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
470 
471         } else if (strncmp((char *)packet, HSP_HS_SPEAKER_GAIN, strlen(HSP_HS_SPEAKER_GAIN)) == 0){
472             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_SPEAKER_GAIN)]);
473             ag_send_ok = 1;
474             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
475 
476         } else if (strncmp((char *)packet, "AT+", 3) == 0){
477             ag_send_error = 1;
478             if (!hsp_ag_callback) return;
479             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
480             uint8_t * event = packet - 3;
481             event[0] = HCI_EVENT_HSP_META;
482             event[1] = size + 1;
483             event[2] = HSP_SUBEVENT_HS_COMMAND;
484             (*hsp_ag_callback)(event, size+3);
485         }
486 
487         hsp_run();
488         return;
489     }
490 
491     if (packet_type != HCI_EVENT_PACKET) return;
492     uint8_t event = packet[0];
493     bd_addr_t event_addr;
494     uint16_t handle;
495 
496     switch (event) {
497         case BTSTACK_EVENT_STATE:
498             // BTstack activated, get started
499             if (packet[2] == HCI_STATE_WORKING){
500                 printf("BTstack activated, get started .\n");
501             }
502             break;
503 
504         case HCI_EVENT_PIN_CODE_REQUEST:
505             // inform about pin code request
506             printf("Pin code request - using '0000'\n\r");
507             bt_flip_addr(event_addr, &packet[2]);
508             hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000");
509             break;
510         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
511             int index = 2;
512             uint8_t status = packet[index++];
513             sco_handle = little_endian_read_16(packet, index);
514             index+=2;
515             bd_addr_t address;
516             memcpy(address, &packet[index], 6);
517             index+=6;
518             uint8_t link_type = packet[index++];
519             uint8_t transmission_interval = packet[index++];  // measured in slots
520             uint8_t retransmission_interval = packet[index++];// measured in slots
521             uint16_t rx_packet_length = little_endian_read_16(packet, index); // measured in bytes
522             index+=2;
523             uint16_t tx_packet_length = little_endian_read_16(packet, index); // measured in bytes
524             index+=2;
525             uint8_t air_mode = packet[index];
526 
527             if (status != 0){
528                 log_error("(e)SCO Connection failed, status %u", status);
529                 emit_event_audio_connected(status, sco_handle);
530                 break;
531             }
532             switch (link_type){
533                 case 0x00:
534                     printf("SCO Connection established. \n");
535                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
536                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
537                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
538                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
539                     break;
540                 case 0x02:
541                     printf("eSCO Connection established. \n");
542                     break;
543                 default:
544                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
545                     break;
546             }
547             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
548                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
549                  bd_addr_to_str(address), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
550 
551             if (hsp_state == HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
552                 hsp_state = HSP_W2_DISCONNECT_SCO;
553                 break;
554             }
555 
556             hsp_state = HSP_ACTIVE;
557             emit_event_audio_connected(status, sco_handle);
558             break;
559         }
560 
561         case RFCOMM_EVENT_INCOMING_CONNECTION:
562             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
563             if (hsp_state != HSP_IDLE) return;
564 
565             bt_flip_addr(event_addr, &packet[2]);
566             rfcomm_cid = little_endian_read_16(packet, 9);
567             printf("RFCOMM channel %u requested for %s\n", packet[8], bd_addr_to_str(event_addr));
568             rfcomm_accept_connection(rfcomm_cid);
569 
570             hsp_state = HSP_W4_RFCOMM_CONNECTED;
571 
572             break;
573 
574         case RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE:
575             printf("RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
576             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
577             if (packet[2]) {
578                 printf("RFCOMM channel open failed, status %u\n", packet[2]);
579                 hsp_ag_reset_state();
580                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, packet[2]);
581             } else {
582                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
583                 rfcomm_handle = little_endian_read_16(packet, 9);
584                 rfcomm_cid = little_endian_read_16(packet, 12);
585                 mtu = little_endian_read_16(packet, 14);
586                 printf("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, state %d\n", rfcomm_cid, mtu, hsp_state);
587 
588                 switch (hsp_state){
589                     case HSP_W4_RFCOMM_CONNECTED:
590                         ag_num_button_press_received = 0;
591                         hsp_state = HSP_W2_CONNECT_SCO;
592                         break;
593                     case HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN:
594                         hsp_state = HSP_W2_DISCONNECT_RFCOMM;
595                         break;
596                     default:
597                         printf("no valid state\n");
598                         break;
599                 }
600             }
601             break;
602         case DAEMON_EVENT_HCI_PACKET_SENT:
603         case RFCOMM_EVENT_CREDITS:
604             break;
605 
606         case HCI_EVENT_DISCONNECTION_COMPLETE:
607             if (hsp_state != HSP_W4_SCO_DISCONNECTED){
608                 log_info("received gap disconnect in wrong hsp state");
609             }
610             handle = little_endian_read_16(packet,3);
611             if (handle == sco_handle){
612                 printf("SCO disconnected, w2 disconnect RFCOMM\n");
613                 sco_handle = 0;
614                 hsp_state = HSP_W2_DISCONNECT_RFCOMM;
615                 break;
616             }
617             break;
618         case RFCOMM_EVENT_CHANNEL_CLOSED:
619             if (hsp_state != HSP_W4_RFCOMM_DISCONNECTED){
620                 log_info("received RFCOMM disconnect in wrong hsp state");
621             }
622             printf("RFCOMM channel closed\n");
623             hsp_ag_reset_state();
624             emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
625             break;
626         default:
627             break;
628     }
629     hsp_run();
630 }
631 
632 static void handle_query_rfcomm_event(uint8_t packet_type, uint8_t *packet, uint16_t size){
633     switch (packet[0]){
634         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
635             channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
636             printf("** Service name: '%s', RFCOMM port %u\n", sdp_event_query_rfcomm_service_get_name(packet), channel_nr);
637             break;
638         case SDP_EVENT_QUERY_COMPLETE:
639             if (channel_nr > 0){
640                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
641                 printf("RFCOMM create channel. state %d\n", HSP_W4_RFCOMM_CONNECTED);
642                 rfcomm_create_channel(remote, channel_nr, NULL);
643                 break;
644             }
645             hsp_ag_reset_state();
646             printf("Service not found, status %u.\n", sdp_event_query_complete_get_status(packet));
647             if (sdp_event_query_complete_get_status(packet)){
648                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, sdp_event_query_complete_get_status(packet));
649             } else {
650                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
651             }
652             break;
653         default:
654             break;
655     }
656 }
657 
658 
659