xref: /btstack/src/classic/hsp_hs.c (revision df25739fc3ea5a0a90f0f5925e6461d653697d2e)
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
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30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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33  * Please inquire about commercial licensing options at
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35  *
36  */
37 
38 // *****************************************************************************
39 //
40 // HSP Headset
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_hs.h"
63 #include "l2cap.h"
64 
65 #define HSP_AG_OK "OK"
66 #define HSP_AG_ERROR "ERROR"
67 #define HSP_AG_RING "RING"
68 #define HSP_MICROPHONE_GAIN "+VGM="
69 #define HSP_SPEAKER_GAIN "+VGS="
70 
71 #define HSP_HS_AT_CKPD "AT+CKPD=200\r\n"
72 #define HSP_HS_MICROPHONE_GAIN "AT+VGM"
73 #define HSP_HS_SPEAKER_GAIN "AT+VGS"
74 
75 static const char default_hsp_hs_service_name[] = "Headset";
76 
77 static bd_addr_t remote = {0x04, 0x0C, 0xCE, 0xE4, 0x85, 0xD3};
78 static uint8_t channel_nr = 0;
79 
80 static uint16_t mtu;
81 static uint16_t rfcomm_cid = 0;
82 static uint16_t sco_handle = 0;
83 static uint16_t rfcomm_handle = 0;
84 
85 // static uint8_t connection_state = 0;
86 
87 static int hs_microphone_gain = -1;
88 static int hs_speaker_gain = -1;
89 
90 static uint8_t hs_send_button_press = 0;
91 static uint8_t wait_ok = 0;
92 
93 static uint8_t hs_support_custom_indications = 0;
94 static btstack_packet_callback_registration_t hci_event_callback_registration;
95 static uint8_t hsp_disconnect_rfcomm = 0;
96 static uint8_t hsp_establish_audio_connection = 0;
97 static uint8_t hsp_release_audio_connection = 0;
98 
99 typedef enum {
100     HSP_IDLE,
101     HSP_SDP_QUERY_RFCOMM_CHANNEL,
102     HSP_W4_SDP_QUERY_COMPLETE,
103     HSP_W4_RFCOMM_CONNECTED,
104 
105     HSP_RFCOMM_CONNECTION_ESTABLISHED,
106 
107     HSP_W2_CONNECT_SCO,
108     HSP_W4_SCO_CONNECTED,
109 
110     HSP_AUDIO_CONNECTION_ESTABLISHED,
111 
112     HSP_W2_DISCONNECT_SCO,
113     HSP_W4_SCO_DISCONNECTED,
114 
115     HSP_W2_DISCONNECT_RFCOMM,
116     HSP_W4_RFCOMM_DISCONNECTED,
117     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
118 } hsp_state_t;
119 
120 static hsp_state_t hsp_state = HSP_IDLE;
121 
122 static void hsp_run(void);
123 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
124 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
125 
126 static hsp_hs_callback_t hsp_hs_callback;
127 static void dummy_notify(uint8_t * event, uint16_t size){}
128 
129 void hsp_hs_register_packet_handler(hsp_hs_callback_t callback){
130     if (callback == NULL){
131         callback = &dummy_notify;
132     }
133     hsp_hs_callback = callback;
134 }
135 
136 static void emit_event(uint8_t event_subtype, uint8_t value){
137     if (!hsp_hs_callback) return;
138     uint8_t event[4];
139     event[0] = HCI_EVENT_HSP_META;
140     event[1] = sizeof(event) - 2;
141     event[2] = event_subtype;
142     event[3] = value; // status 0 == OK
143     (*hsp_hs_callback)(event, sizeof(event));
144 }
145 
146 static void emit_ring_event(void){
147     if (!hsp_hs_callback) return;
148     uint8_t event[3];
149     event[0] = HCI_EVENT_HSP_META;
150     event[1] = sizeof(event) - 2;
151     event[2] = HSP_SUBEVENT_RING;
152     (*hsp_hs_callback)(event, sizeof(event));
153 }
154 
155 static void emit_event_audio_connected(uint8_t status, uint16_t handle){
156     if (!hsp_hs_callback) return;
157     uint8_t event[6];
158     event[0] = HCI_EVENT_HSP_META;
159     event[1] = sizeof(event) - 2;
160     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
161     event[3] = status;
162     little_endian_store_16(event, 4, handle);
163     (*hsp_hs_callback)(event, sizeof(event));
164 }
165 
166 // remote audio volume control
167 // AG +VGM=13 [0..15] ; HS AT+VGM=6 | AG OK
168 
169 static int hsp_hs_send_str_over_rfcomm(uint16_t cid, const char * command){
170     if (!rfcomm_can_send_packet_now(rfcomm_cid)) return 1;
171     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
172     if (err){
173         log_info("rfcomm_send_internal -> error 0X%02x", err);
174     }
175     return err;
176 }
177 
178 void hsp_hs_enable_custom_indications(int enable){
179     hs_support_custom_indications = enable;
180 }
181 
182 int hsp_hs_send_result(const char * result){
183     if (!hs_support_custom_indications) return 1;
184     return hsp_hs_send_str_over_rfcomm(rfcomm_cid, result);
185 }
186 
187 
188 void hsp_hs_create_sdp_record(uint8_t * service,  uint32_t service_record_handle, int rfcomm_channel_nr, const char * name, uint8_t have_remote_audio_control){
189     uint8_t* attribute;
190     de_create_sequence(service);
191 
192     // 0x0000 "Service Record Handle"
193     de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
194     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
195 
196     // 0x0001 "Service Class ID List"
197     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
198     attribute = de_push_sequence(service);
199     {
200         //  see Bluetooth Erratum #3507
201         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_HSP);          // 0x1108
202         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_HS);   // 0x1131
203         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio); // 0x1203
204     }
205     de_pop_sequence(service, attribute);
206 
207     // 0x0004 "Protocol Descriptor List"
208     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
209     attribute = de_push_sequence(service);
210     {
211         uint8_t* l2cpProtocol = de_push_sequence(attribute);
212         {
213             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
214         }
215         de_pop_sequence(attribute, l2cpProtocol);
216 
217         uint8_t* rfcomm = de_push_sequence(attribute);
218         {
219             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol);  // rfcomm_service
220             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
221         }
222         de_pop_sequence(attribute, rfcomm);
223     }
224     de_pop_sequence(service, attribute);
225 
226     // 0x0005 "Public Browse Group"
227     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
228     attribute = de_push_sequence(service);
229     {
230         de_add_number(attribute,  DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
231     }
232     de_pop_sequence(service, attribute);
233 
234     // 0x0009 "Bluetooth Profile Descriptor List"
235     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
236     attribute = de_push_sequence(service);
237     {
238         uint8_t *hsp_profile = de_push_sequence(attribute);
239         {
240             de_add_number(hsp_profile,  DE_UUID, DE_SIZE_16, SDP_HSP);
241             de_add_number(hsp_profile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
242         }
243         de_pop_sequence(attribute, hsp_profile);
244     }
245     de_pop_sequence(service, attribute);
246 
247     // 0x0100 "Service Name"
248     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
249     if (name){
250         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
251     } else {
252         de_add_data(service,  DE_STRING, strlen(default_hsp_hs_service_name), (uint8_t *) default_hsp_hs_service_name);
253     }
254 
255     // Remote audio volume control
256     de_add_number(service, DE_UINT, DE_SIZE_16, 0x030C);
257     de_add_number(service, DE_BOOL, DE_SIZE_8, have_remote_audio_control);
258 }
259 
260 static void hsp_hs_reset_state(void){
261     hsp_state = HSP_IDLE;
262     hs_microphone_gain = -1;
263     hs_speaker_gain = -1;
264 
265     hs_send_button_press = 0;
266     wait_ok = 0;
267     hs_support_custom_indications = 0;
268 
269     hsp_disconnect_rfcomm = 0;
270     hsp_establish_audio_connection = 0;
271     hsp_release_audio_connection = 0;
272 }
273 
274 void hsp_hs_init(uint8_t rfcomm_channel_nr){
275     // register for HCI events
276     hci_event_callback_registration.callback = &packet_handler;
277     hci_add_event_handler(&hci_event_callback_registration);
278 
279     // init L2CAP
280     l2cap_init();
281 
282     rfcomm_init();
283     rfcomm_register_service(packet_handler, rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
284 
285     hsp_hs_reset_state();
286 }
287 
288 
289 void hsp_hs_connect(bd_addr_t bd_addr){
290     if (hsp_state != HSP_IDLE) return;
291     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
292     memcpy(remote, bd_addr, 6);
293     hsp_run();
294 }
295 
296 void hsp_hs_disconnect(void){
297     hsp_hs_release_audio_connection();
298 
299     if (hsp_state < HSP_W4_RFCOMM_CONNECTED){
300         hsp_state = HSP_IDLE;
301         return;
302     }
303 
304     if (hsp_state == HSP_W4_RFCOMM_CONNECTED){
305         hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
306         return;
307     }
308 
309     if (hsp_state < HSP_W4_SCO_CONNECTED){
310         hsp_state = HSP_W2_DISCONNECT_RFCOMM;
311         return;
312     }
313 
314     hsp_disconnect_rfcomm = 1;
315     hsp_run();
316 }
317 
318 
319 void hsp_hs_establish_audio_connection(void){
320     switch (hsp_state){
321         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
322             hsp_establish_audio_connection = 1;
323             hsp_state = HSP_W4_SCO_CONNECTED;
324             break;
325         case HSP_W4_RFCOMM_CONNECTED:
326             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
327             break;
328         default:
329             break;
330     }
331     hsp_run();
332 }
333 
334 void hsp_hs_release_audio_connection(void){
335     if (hsp_state >= HSP_W2_DISCONNECT_SCO) return;
336     if (hsp_state < HSP_AUDIO_CONNECTION_ESTABLISHED) return;
337     hsp_release_audio_connection = 1;
338     hsp_run();
339 }
340 
341 void hsp_hs_set_microphone_gain(uint8_t gain){
342     if (gain < 0 || gain >15) {
343         log_info("Gain must be in interval [0..15], it is given %d", gain);
344         return;
345     }
346     hs_microphone_gain = gain;
347     hsp_run();
348 }
349 
350 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
351 void hsp_hs_set_speaker_gain(uint8_t gain){
352     if (gain < 0 || gain >15) {
353         log_info("Gain must be in interval [0..15], it is given %d", gain);
354         return;
355     }
356     hs_speaker_gain = gain;
357     hsp_run();
358 }
359 
360 
361 static void hsp_run(void){
362 
363     if (wait_ok) return;
364 
365     if (hsp_release_audio_connection){
366         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
367             rfcomm_request_can_send_now_event(rfcomm_cid);
368             return;
369         }
370         hsp_release_audio_connection = 0;
371         wait_ok = 1;
372         hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
373         return;
374     }
375 
376     if (hsp_disconnect_rfcomm){
377         hsp_disconnect_rfcomm = 0;
378         hsp_establish_audio_connection = 0;
379         rfcomm_disconnect(rfcomm_cid);
380         return;
381     }
382 
383     if (hsp_establish_audio_connection){
384         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
385             rfcomm_request_can_send_now_event(rfcomm_cid);
386             return;
387         }
388         hsp_establish_audio_connection = 0;
389         wait_ok = 1;
390         hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
391         return;
392     }
393 
394     if (hs_send_button_press){
395         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
396             rfcomm_request_can_send_now_event(rfcomm_cid);
397             return;
398         }
399         hs_send_button_press = 0;
400         wait_ok = 1;
401         hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
402         return;
403     }
404 
405     switch (hsp_state){
406         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
407             hsp_state = HSP_W4_SDP_QUERY_COMPLETE;
408             sdp_client_query_rfcomm_channel_and_name_for_uuid(&handle_query_rfcomm_event, remote, SDP_Headset_AG);
409             break;
410 
411         case HSP_AUDIO_CONNECTION_ESTABLISHED:
412         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
413 
414             if (hs_microphone_gain >= 0){
415                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
416                     rfcomm_request_can_send_now_event(rfcomm_cid);
417                     return;
418                 }
419                 char buffer[20];
420                 sprintf(buffer, "%s=%d\r\n", HSP_HS_MICROPHONE_GAIN, hs_microphone_gain);
421                 hsp_hs_send_str_over_rfcomm(rfcomm_cid, buffer);
422                 hs_microphone_gain = -1;
423                 break;
424             }
425 
426             if (hs_speaker_gain >= 0){
427                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
428                     rfcomm_request_can_send_now_event(rfcomm_cid);
429                     return;
430                 }
431                 char buffer[20];
432                 sprintf(buffer, "%s=%d\r\n", HSP_HS_SPEAKER_GAIN, hs_speaker_gain);
433                 hsp_hs_send_str_over_rfcomm(rfcomm_cid, buffer);
434                 hs_speaker_gain = -1;
435                 break;
436             }
437             break;
438         case HSP_W4_RFCOMM_DISCONNECTED:
439             rfcomm_disconnect(rfcomm_cid);
440             break;
441         default:
442             break;
443     }
444 }
445 
446 
447 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
448     // printf("packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
449     if (packet_type == RFCOMM_DATA_PACKET){
450         // skip over leading newline
451         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
452             size--;
453             packet++;
454         }
455         if (strncmp((char *)packet, HSP_AG_RING, strlen(HSP_AG_RING)) == 0){
456             emit_ring_event();
457         } else if (strncmp((char *)packet, HSP_AG_OK, strlen(HSP_AG_OK)) == 0){
458            wait_ok = 0;
459         } else if (strncmp((char *)packet, HSP_MICROPHONE_GAIN, strlen(HSP_MICROPHONE_GAIN)) == 0){
460             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_MICROPHONE_GAIN)]);
461             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
462 
463         } else if (strncmp((char *)packet, HSP_SPEAKER_GAIN, strlen(HSP_SPEAKER_GAIN)) == 0){
464             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_SPEAKER_GAIN)]);
465             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
466         } else {
467             if (!hsp_hs_callback) return;
468             // strip trailing newline
469             while (size > 0 && (packet[size-1] == '\n' || packet[size-1] == '\r')){
470                 size--;
471             }
472             // add trailing \0
473             packet[size] = 0;
474             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
475             uint8_t * event = packet - 4;
476             event[0] = HCI_EVENT_HSP_META;
477             event[1] = size + 2;
478             event[2] = HSP_SUBEVENT_AG_INDICATION;
479             event[3] = size;
480             (*hsp_hs_callback)(event, size+4);
481         }
482         hsp_run();
483         return;
484     }
485 
486     if (packet_type != HCI_EVENT_PACKET) return;
487     uint8_t event = hci_event_packet_get_type(packet);
488     bd_addr_t event_addr;
489     uint16_t handle;
490 
491     switch (event) {
492         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
493             if (hsp_state < HSP_RFCOMM_CONNECTION_ESTABLISHED) return;
494             int index = 2;
495             uint8_t status = packet[index++];
496             sco_handle = little_endian_read_16(packet, index);
497             index+=2;
498             bd_addr_t address;
499             memcpy(address, &packet[index], 6);
500             index+=6;
501             uint8_t link_type = packet[index++];
502             uint8_t transmission_interval = packet[index++];  // measured in slots
503             uint8_t retransmission_interval = packet[index++];// measured in slots
504             uint16_t rx_packet_length = little_endian_read_16(packet, index); // measured in bytes
505             index+=2;
506             uint16_t tx_packet_length = little_endian_read_16(packet, index); // measured in bytes
507             index+=2;
508             uint8_t air_mode = packet[index];
509 
510             if (status != 0){
511                 log_error("(e)SCO Connection failed, status %u", status);
512                 emit_event_audio_connected(status, sco_handle);
513                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED ;
514                 break;
515             }
516 
517             switch (link_type){
518                 case 0x00:
519                     log_info("SCO Connection established.");
520                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
521                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
522                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
523                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
524                     break;
525                 case 0x02:
526                     log_info("eSCO Connection established.");
527                     break;
528                 default:
529                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
530                     break;
531             }
532             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
533                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
534                  bd_addr_to_str(address), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
535 
536             hsp_state = HSP_AUDIO_CONNECTION_ESTABLISHED;
537             emit_event_audio_connected(status, sco_handle);
538             break;
539         }
540 
541         case RFCOMM_EVENT_INCOMING_CONNECTION:
542             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
543             if (hsp_state != HSP_IDLE) return;
544 
545             reverse_bd_addr(&packet[2], event_addr);
546             rfcomm_cid = little_endian_read_16(packet, 9);
547             log_info("RFCOMM channel %u requested for %s", packet[8], bd_addr_to_str(event_addr));
548             hsp_state = HSP_W4_RFCOMM_CONNECTED;
549             rfcomm_accept_connection(rfcomm_cid);
550             break;
551 
552         case RFCOMM_EVENT_CHANNEL_OPENED:
553             // printf("RFCOMM_EVENT_CHANNEL_OPENED packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
554             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
555             if (hsp_state != HSP_W4_RFCOMM_CONNECTED) return;
556             if (packet[2]) {
557                 log_info("RFCOMM channel open failed, status %u", packet[2]);
558                 hsp_state = HSP_IDLE;
559                 hsp_hs_reset_state();
560             } else {
561                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
562                 rfcomm_handle = little_endian_read_16(packet, 9);
563                 rfcomm_cid = little_endian_read_16(packet, 12);
564                 mtu = little_endian_read_16(packet, 14);
565                 log_info("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, handle %02x", rfcomm_cid, mtu, rfcomm_handle);
566                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
567             }
568             emit_event(HSP_SUBEVENT_RFCOMM_CONNECTION_COMPLETE, packet[2]);
569             break;
570 
571         case RFCOMM_EVENT_CAN_SEND_NOW:
572             hsp_run();
573             break;
574 
575         case HCI_EVENT_DISCONNECTION_COMPLETE:
576             handle = little_endian_read_16(packet,3);
577             if (handle == sco_handle){
578                 sco_handle = 0;
579                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
580                 emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
581                 break;
582             }
583             if (handle == rfcomm_handle) {
584                 rfcomm_handle = 0;
585                 hsp_state = HSP_IDLE;
586                 emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE,0);
587                 hsp_hs_reset_state();
588             }
589             break;
590 
591         case RFCOMM_EVENT_CHANNEL_CLOSED:
592             hsp_hs_reset_state();
593             hsp_hs_callback(packet, size);
594             break;
595 
596         default:
597             break;
598     }
599 
600     hsp_run();
601 }
602 
603 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
604     switch (hci_event_packet_get_type(packet)){
605         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
606             channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
607             log_info("** Service name: '%s', RFCOMM port %u", sdp_event_query_rfcomm_service_get_name(packet), channel_nr);
608             break;
609         case SDP_EVENT_QUERY_COMPLETE:
610             if (channel_nr > 0){
611                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
612                 log_info("HSP: SDP_QUERY_COMPLETE. RFCOMM create channel, addr %s, rfcomm channel nr %d", bd_addr_to_str(remote), channel_nr);
613                 rfcomm_create_channel(packet_handler, remote, channel_nr, NULL);
614                 break;
615             }
616             hsp_hs_reset_state();
617             log_info("Service not found, status %u.", sdp_event_query_complete_get_status(packet));
618             break;
619     }
620 }
621 
622 void hsp_hs_send_button_press(void){
623     if (hsp_state < HSP_RFCOMM_CONNECTION_ESTABLISHED || hsp_state >= HSP_W4_RFCOMM_DISCONNECTED) return;
624     hs_send_button_press = 1;
625     hsp_run();
626 }
627