xref: /btstack/src/classic/hsp_hs.c (revision bc37f7b0d0a3eaa5763a873c5730bc14b849aaa0)
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.
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33  * Please inquire about commercial licensing options at
34  * [email protected]
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 btstack_packet_handler_t hsp_hs_callback;
127 static void dummy_notify(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t size){}
128 
129 void hsp_hs_register_packet_handler(btstack_packet_handler_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)(HCI_EVENT_PACKET, 0, 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)(HCI_EVENT_PACKET, 0, 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)(HCI_EVENT_PACKET, 0, 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     rfcomm_init();
280     rfcomm_register_service(packet_handler, rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
281 
282     hsp_hs_reset_state();
283 }
284 
285 
286 void hsp_hs_connect(bd_addr_t bd_addr){
287     if (hsp_state != HSP_IDLE) return;
288     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
289     memcpy(remote, bd_addr, 6);
290     hsp_run();
291 }
292 
293 void hsp_hs_disconnect(void){
294     hsp_hs_release_audio_connection();
295 
296     if (hsp_state < HSP_W4_RFCOMM_CONNECTED){
297         hsp_state = HSP_IDLE;
298         return;
299     }
300 
301     if (hsp_state == HSP_W4_RFCOMM_CONNECTED){
302         hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
303         return;
304     }
305 
306     if (hsp_state < HSP_W4_SCO_CONNECTED){
307         hsp_state = HSP_W2_DISCONNECT_RFCOMM;
308         return;
309     }
310 
311     hsp_disconnect_rfcomm = 1;
312     hsp_run();
313 }
314 
315 
316 void hsp_hs_establish_audio_connection(void){
317     switch (hsp_state){
318         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
319             hsp_establish_audio_connection = 1;
320             hsp_state = HSP_W4_SCO_CONNECTED;
321             break;
322         case HSP_W4_RFCOMM_CONNECTED:
323             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
324             break;
325         default:
326             break;
327     }
328     hsp_run();
329 }
330 
331 void hsp_hs_release_audio_connection(void){
332     if (hsp_state >= HSP_W2_DISCONNECT_SCO) return;
333     if (hsp_state < HSP_AUDIO_CONNECTION_ESTABLISHED) return;
334     hsp_release_audio_connection = 1;
335     hsp_run();
336 }
337 
338 void hsp_hs_set_microphone_gain(uint8_t gain){
339     if (gain < 0 || gain >15) {
340         log_info("Gain must be in interval [0..15], it is given %d", gain);
341         return;
342     }
343     hs_microphone_gain = gain;
344     hsp_run();
345 }
346 
347 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
348 void hsp_hs_set_speaker_gain(uint8_t gain){
349     if (gain < 0 || gain >15) {
350         log_info("Gain must be in interval [0..15], it is given %d", gain);
351         return;
352     }
353     hs_speaker_gain = gain;
354     hsp_run();
355 }
356 
357 
358 static void hsp_run(void){
359 
360     if (wait_ok) return;
361 
362     if (hsp_release_audio_connection){
363         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
364             rfcomm_request_can_send_now_event(rfcomm_cid);
365             return;
366         }
367         hsp_release_audio_connection = 0;
368         wait_ok = 1;
369         hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
370         return;
371     }
372 
373     if (hsp_disconnect_rfcomm){
374         hsp_disconnect_rfcomm = 0;
375         hsp_establish_audio_connection = 0;
376         rfcomm_disconnect(rfcomm_cid);
377         return;
378     }
379 
380     if (hsp_establish_audio_connection){
381         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
382             rfcomm_request_can_send_now_event(rfcomm_cid);
383             return;
384         }
385         hsp_establish_audio_connection = 0;
386         wait_ok = 1;
387         hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
388         return;
389     }
390 
391     if (hs_send_button_press){
392         if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
393             rfcomm_request_can_send_now_event(rfcomm_cid);
394             return;
395         }
396         hs_send_button_press = 0;
397         wait_ok = 1;
398         hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
399         return;
400     }
401 
402     switch (hsp_state){
403         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
404             hsp_state = HSP_W4_SDP_QUERY_COMPLETE;
405             sdp_client_query_rfcomm_channel_and_name_for_uuid(&handle_query_rfcomm_event, remote, SDP_Headset_AG);
406             break;
407 
408         case HSP_AUDIO_CONNECTION_ESTABLISHED:
409         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
410 
411             if (hs_microphone_gain >= 0){
412                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
413                     rfcomm_request_can_send_now_event(rfcomm_cid);
414                     return;
415                 }
416                 char buffer[20];
417                 sprintf(buffer, "%s=%d\r\n", HSP_HS_MICROPHONE_GAIN, hs_microphone_gain);
418                 hsp_hs_send_str_over_rfcomm(rfcomm_cid, buffer);
419                 hs_microphone_gain = -1;
420                 break;
421             }
422 
423             if (hs_speaker_gain >= 0){
424                 if (!rfcomm_can_send_packet_now(rfcomm_cid)) {
425                     rfcomm_request_can_send_now_event(rfcomm_cid);
426                     return;
427                 }
428                 char buffer[20];
429                 sprintf(buffer, "%s=%d\r\n", HSP_HS_SPEAKER_GAIN, hs_speaker_gain);
430                 hsp_hs_send_str_over_rfcomm(rfcomm_cid, buffer);
431                 hs_speaker_gain = -1;
432                 break;
433             }
434             break;
435         case HSP_W4_RFCOMM_DISCONNECTED:
436             rfcomm_disconnect(rfcomm_cid);
437             break;
438         default:
439             break;
440     }
441 }
442 
443 
444 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
445     // printf("packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
446     if (packet_type == RFCOMM_DATA_PACKET){
447         // skip over leading newline
448         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
449             size--;
450             packet++;
451         }
452         if (strncmp((char *)packet, HSP_AG_RING, strlen(HSP_AG_RING)) == 0){
453             emit_ring_event();
454         } else if (strncmp((char *)packet, HSP_AG_OK, strlen(HSP_AG_OK)) == 0){
455            wait_ok = 0;
456         } else if (strncmp((char *)packet, HSP_MICROPHONE_GAIN, strlen(HSP_MICROPHONE_GAIN)) == 0){
457             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_MICROPHONE_GAIN)]);
458             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
459 
460         } else if (strncmp((char *)packet, HSP_SPEAKER_GAIN, strlen(HSP_SPEAKER_GAIN)) == 0){
461             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_SPEAKER_GAIN)]);
462             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
463         } else {
464             if (!hsp_hs_callback) return;
465             // strip trailing newline
466             while (size > 0 && (packet[size-1] == '\n' || packet[size-1] == '\r')){
467                 size--;
468             }
469             // add trailing \0
470             packet[size] = 0;
471             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
472             uint8_t * event = packet - 4;
473             event[0] = HCI_EVENT_HSP_META;
474             event[1] = size + 2;
475             event[2] = HSP_SUBEVENT_AG_INDICATION;
476             event[3] = size;
477             (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, size+4);
478         }
479         hsp_run();
480         return;
481     }
482 
483     if (packet_type != HCI_EVENT_PACKET) return;
484     uint8_t event = hci_event_packet_get_type(packet);
485     bd_addr_t event_addr;
486     uint16_t handle;
487 
488     switch (event) {
489         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
490             if (hsp_state < HSP_RFCOMM_CONNECTION_ESTABLISHED) return;
491             int index = 2;
492             uint8_t status = packet[index++];
493             sco_handle = little_endian_read_16(packet, index);
494             index+=2;
495             bd_addr_t address;
496             memcpy(address, &packet[index], 6);
497             index+=6;
498             uint8_t link_type = packet[index++];
499             uint8_t transmission_interval = packet[index++];  // measured in slots
500             uint8_t retransmission_interval = packet[index++];// measured in slots
501             uint16_t rx_packet_length = little_endian_read_16(packet, index); // measured in bytes
502             index+=2;
503             uint16_t tx_packet_length = little_endian_read_16(packet, index); // measured in bytes
504             index+=2;
505             uint8_t air_mode = packet[index];
506 
507             if (status != 0){
508                 log_error("(e)SCO Connection failed, status %u", status);
509                 emit_event_audio_connected(status, sco_handle);
510                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED ;
511                 break;
512             }
513 
514             switch (link_type){
515                 case 0x00:
516                     log_info("SCO Connection established.");
517                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
518                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
519                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
520                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
521                     break;
522                 case 0x02:
523                     log_info("eSCO Connection established.");
524                     break;
525                 default:
526                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
527                     break;
528             }
529             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
530                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
531                  bd_addr_to_str(address), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
532 
533             hsp_state = HSP_AUDIO_CONNECTION_ESTABLISHED;
534             emit_event_audio_connected(status, sco_handle);
535             break;
536         }
537 
538         case RFCOMM_EVENT_INCOMING_CONNECTION:
539             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
540             if (hsp_state != HSP_IDLE) return;
541 
542             reverse_bd_addr(&packet[2], event_addr);
543             rfcomm_cid = little_endian_read_16(packet, 9);
544             log_info("RFCOMM channel %u requested for %s", packet[8], bd_addr_to_str(event_addr));
545             hsp_state = HSP_W4_RFCOMM_CONNECTED;
546             rfcomm_accept_connection(rfcomm_cid);
547             break;
548 
549         case RFCOMM_EVENT_CHANNEL_OPENED:
550             // printf("RFCOMM_EVENT_CHANNEL_OPENED packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
551             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
552             if (hsp_state != HSP_W4_RFCOMM_CONNECTED) return;
553             if (packet[2]) {
554                 log_info("RFCOMM channel open failed, status %u", packet[2]);
555                 hsp_state = HSP_IDLE;
556                 hsp_hs_reset_state();
557             } else {
558                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
559                 rfcomm_handle = little_endian_read_16(packet, 9);
560                 rfcomm_cid = little_endian_read_16(packet, 12);
561                 mtu = little_endian_read_16(packet, 14);
562                 log_info("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, handle %02x", rfcomm_cid, mtu, rfcomm_handle);
563                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
564             }
565             emit_event(HSP_SUBEVENT_RFCOMM_CONNECTION_COMPLETE, packet[2]);
566             break;
567 
568         case RFCOMM_EVENT_CAN_SEND_NOW:
569             hsp_run();
570             break;
571 
572         case HCI_EVENT_DISCONNECTION_COMPLETE:
573             handle = little_endian_read_16(packet,3);
574             if (handle == sco_handle){
575                 sco_handle = 0;
576                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
577                 emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
578                 break;
579             }
580             if (handle == rfcomm_handle) {
581                 rfcomm_handle = 0;
582                 hsp_state = HSP_IDLE;
583                 emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE,0);
584                 hsp_hs_reset_state();
585             }
586             break;
587 
588         case RFCOMM_EVENT_CHANNEL_CLOSED:
589             hsp_hs_reset_state();
590             hsp_hs_callback(HCI_EVENT_PACKET, 0, packet, size);
591             break;
592 
593         default:
594             break;
595     }
596 
597     hsp_run();
598 }
599 
600 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
601     switch (hci_event_packet_get_type(packet)){
602         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
603             channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
604             log_info("** Service name: '%s', RFCOMM port %u", sdp_event_query_rfcomm_service_get_name(packet), channel_nr);
605             break;
606         case SDP_EVENT_QUERY_COMPLETE:
607             if (channel_nr > 0){
608                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
609                 log_info("HSP: SDP_QUERY_COMPLETE. RFCOMM create channel, addr %s, rfcomm channel nr %d", bd_addr_to_str(remote), channel_nr);
610                 rfcomm_create_channel(packet_handler, remote, channel_nr, NULL);
611                 break;
612             }
613             hsp_hs_reset_state();
614             log_info("Service not found, status %u.", sdp_event_query_complete_get_status(packet));
615             break;
616     }
617 }
618 
619 void hsp_hs_send_button_press(void){
620     if (hsp_state < HSP_RFCOMM_CONNECTION_ESTABLISHED || hsp_state >= HSP_W4_RFCOMM_DISCONNECTED) return;
621     hs_send_button_press = 1;
622     hsp_run();
623 }
624