xref: /btstack/src/classic/hsp_hs.c (revision af7c3ae6cd1e2bcfd24e6d0654508ecf775c9e5d)
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 BLUEKITCHEN
24  * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hsp_hs.c"
39 
40 // *****************************************************************************
41 //
42 // HSP Headset
43 //
44 // *****************************************************************************
45 
46 #include "btstack_config.h"
47 
48 #include <stdint.h>
49 #include <stdio.h>
50 #include <string.h>
51 
52 #include "bluetooth_sdp.h"
53 #include "btstack_debug.h"
54 #include "btstack_event.h"
55 #include "btstack_memory.h"
56 #include "btstack_run_loop.h"
57 #include "classic/core.h"
58 #include "classic/sdp_server.h"
59 #include "classic/sdp_client_rfcomm.h"
60 #include "classic/sdp_util.h"
61 #include "classic/sdp_client.h"
62 #include "hci.h"
63 #include "hci_cmd.h"
64 #include "hci_dump.h"
65 #include "hsp_hs.h"
66 #include "l2cap.h"
67 
68 #define HSP_AG_OK "OK"
69 #define HSP_AG_ERROR "ERROR"
70 #define HSP_AG_RING "RING"
71 #define HSP_MICROPHONE_GAIN "+VGM="
72 #define HSP_SPEAKER_GAIN "+VGS="
73 
74 #define HSP_HS_AT_CKPD "AT+CKPD=200\r\n"
75 #define HSP_HS_MICROPHONE_GAIN "AT+VGM"
76 #define HSP_HS_SPEAKER_GAIN "AT+VGS"
77 
78 static const char hsp_hs_default_service_name[] = "Headset";
79 
80 typedef enum {
81     HSP_IDLE,
82     HSP_W2_SEND_SDP_QUERY,
83     HSP_W4_SDP_QUERY_COMPLETE,
84     HSP_W4_RFCOMM_CONNECTED,
85 
86     HSP_RFCOMM_CONNECTION_ESTABLISHED,
87 
88     HSP_W2_CONNECT_SCO,
89     HSP_W4_SCO_CONNECTED,
90 
91     HSP_AUDIO_CONNECTION_ESTABLISHED,
92 
93     HSP_W2_DISCONNECT_SCO,
94     HSP_W4_SCO_DISCONNECTED,
95 
96     HSP_W2_DISCONNECT_RFCOMM,
97     HSP_W4_RFCOMM_DISCONNECTED,
98     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
99 } hsp_state_t;
100 
101 // higher-layer callbacks
102 static btstack_packet_handler_t hsp_hs_callback;
103 
104 static bd_addr_t hsp_hs_remote;
105 static uint8_t   hsp_hs_rfcomm_channel_nr;
106 static uint16_t  hsp_hs_rfcomm_cid;
107 static uint16_t  hsp_hs_rfcomm_mtu;
108 
109 static hci_con_handle_t hsp_hs_sco_handle;
110 static hci_con_handle_t hsp_hs_rfcomm_handle;
111 
112 static hsp_state_t hsp_state;
113 
114 static int hsp_hs_microphone_gain;
115 static int hsp_hs_speaker_gain;
116 
117 static uint8_t hsp_hs_send_button_press_triggered;
118 static uint8_t hsp_hs_wait_ok;
119 static uint8_t hsp_hs_accept_sco_connection;
120 
121 static uint8_t hsp_hs_support_custom_indications;
122 static uint8_t hsp_hs_establish_audio_connection_triggered;
123 static uint8_t hsp_hs_release_audio_connection_triggered;
124 
125 static uint16_t hsp_hs_sco_packet_types;
126 
127 static btstack_packet_callback_registration_t  hsp_hs_hci_event_callback_registration;
128 static btstack_context_callback_registration_t hsp_hs_handle_sdp_client_query_request;
129 
130 #ifdef ENABLE_RTK_PCM_WBS
131 static bool hsp_hs_rtk_send_sco_config;
132 #endif
133 
134 static void hsp_run(void);
135 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
136 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
137 
138 void hsp_hs_register_packet_handler(btstack_packet_handler_t callback){
139     btstack_assert(callback);
140     hsp_hs_callback = callback;
141 }
142 
143 static void emit_event(uint8_t event_subtype){
144     if (!hsp_hs_callback) return;
145     uint8_t event[5];
146     event[0] = HCI_EVENT_HSP_META;
147     event[1] = sizeof(event) - 2;
148     event[2] = event_subtype;
149     little_endian_store_16(event, 3, hsp_hs_rfcomm_handle);
150     (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
151 }
152 
153 static void emit_event_with_value(uint8_t event_subtype, uint8_t value){
154     if (!hsp_hs_callback) return;
155     uint8_t event[6];
156     event[0] = HCI_EVENT_HSP_META;
157     event[1] = sizeof(event) - 2;
158     event[2] = event_subtype;
159     little_endian_store_16(event, 3, hsp_hs_rfcomm_handle);
160     event[5] = value;
161     (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
162 }
163 
164 static void emit_event_rfcomm_connected(uint8_t status){
165     if (!hsp_hs_callback) return;
166     uint8_t event[12];
167     event[0] = HCI_EVENT_HSP_META;
168     event[1] = sizeof(event) - 2;
169     event[2] = HSP_SUBEVENT_RFCOMM_CONNECTION_COMPLETE;
170     little_endian_store_16(event, 3, hsp_hs_rfcomm_handle);
171     event[5] = status;
172     reverse_bd_addr(hsp_hs_remote, &event[6]);
173     (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
174 }
175 
176 static void emit_event_audio_connected(uint8_t status, uint16_t sco_handle){
177     if (!hsp_hs_callback) return;
178     uint8_t event[8];
179     event[0] = HCI_EVENT_HSP_META;
180     event[1] = sizeof(event) - 2;
181     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
182     little_endian_store_16(event, 3, hsp_hs_rfcomm_handle);
183     event[5] = status;
184     little_endian_store_16(event, 6, sco_handle);
185     (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
186 }
187 
188 static void emit_event_audio_disconnected(uint16_t sco_handle){
189     if (!hsp_hs_callback) return;
190     uint8_t event[7];
191     event[0] = HCI_EVENT_HSP_META;
192     event[1] = sizeof(event) - 2;
193     event[2] = HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE;
194     little_endian_store_16(event, 3, hsp_hs_rfcomm_handle);
195     little_endian_store_16(event, 5, sco_handle);
196     (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event));
197 }
198 
199 
200 // remote audio volume control
201 // AG +VGM=13 [0..15] ; HS AT+VGM=6 | AG OK
202 
203 static int hsp_hs_send_str_over_rfcomm(uint16_t cid, const char * command){
204     if (!rfcomm_can_send_packet_now(hsp_hs_rfcomm_cid)) return 1;
205     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
206     if (err){
207         log_info("rfcomm_send_internal -> error 0X%02x", err);
208     }
209     return err;
210 }
211 
212 void hsp_hs_enable_custom_indications(int enable){
213     hsp_hs_support_custom_indications = enable;
214 }
215 
216 int hsp_hs_send_result(const char * result){
217     if (!hsp_hs_support_custom_indications) return 1;
218     return hsp_hs_send_str_over_rfcomm(hsp_hs_rfcomm_cid, result);
219 }
220 
221 
222 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){
223     uint8_t* attribute;
224     de_create_sequence(service);
225 
226     // 0x0000 "Service Record Handle"
227     de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE);
228     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
229 
230     // 0x0001 "Service Class ID List"
231     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST);
232     attribute = de_push_sequence(service);
233     {
234         //  see Bluetooth Erratum #3507
235         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_HEADSET);       // 0x1108
236         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_HEADSET_HS);    // 0x1131
237         de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_GENERIC_AUDIO); // 0x1203
238     }
239     de_pop_sequence(service, attribute);
240 
241     // 0x0004 "Protocol Descriptor List"
242     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST);
243     attribute = de_push_sequence(service);
244     {
245         uint8_t* l2cpProtocol = de_push_sequence(attribute);
246         {
247             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP);
248         }
249         de_pop_sequence(attribute, l2cpProtocol);
250 
251         uint8_t* rfcomm = de_push_sequence(attribute);
252         {
253             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_RFCOMM);  // rfcomm_service
254             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
255         }
256         de_pop_sequence(attribute, rfcomm);
257     }
258     de_pop_sequence(service, attribute);
259 
260     // 0x0005 "Public Browse Group"
261     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group
262     attribute = de_push_sequence(service);
263     {
264         de_add_number(attribute,  DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT);
265     }
266     de_pop_sequence(service, attribute);
267 
268     // 0x0009 "Bluetooth Profile Descriptor List"
269     de_add_number(service,  DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST);
270     attribute = de_push_sequence(service);
271     {
272         uint8_t *hsp_profile = de_push_sequence(attribute);
273         {
274             de_add_number(hsp_profile,  DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_HEADSET);
275             de_add_number(hsp_profile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
276         }
277         de_pop_sequence(attribute, hsp_profile);
278     }
279     de_pop_sequence(service, attribute);
280 
281     // 0x0100 "Service Name"
282     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
283     if (name){
284         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
285     } else {
286         de_add_data(service, DE_STRING, strlen(hsp_hs_default_service_name), (uint8_t *) hsp_hs_default_service_name);
287     }
288 
289     // Remote audio volume control
290     de_add_number(service, DE_UINT, DE_SIZE_16, 0x030C);
291     de_add_number(service, DE_BOOL, DE_SIZE_8, have_remote_audio_control);
292 }
293 
294 static void hsp_hs_reset_state(void){
295     hsp_state = HSP_IDLE;
296     hsp_hs_microphone_gain = -1;
297     hsp_hs_speaker_gain = -1;
298     hsp_hs_rfcomm_cid = 0;
299     hsp_hs_rfcomm_channel_nr = 0;
300     hsp_hs_rfcomm_handle = HCI_CON_HANDLE_INVALID;
301     hsp_hs_sco_handle    = HCI_CON_HANDLE_INVALID;
302 
303     hsp_hs_send_button_press_triggered = 0;
304     hsp_hs_wait_ok = 0;
305     hsp_hs_support_custom_indications = 0;
306 
307     hsp_hs_accept_sco_connection = 0;
308     hsp_hs_establish_audio_connection_triggered = 0;
309     hsp_hs_release_audio_connection_triggered = 0;
310 }
311 
312 void hsp_hs_init(uint8_t rfcomm_channel_nr){
313     // register for HCI events
314     hsp_hs_hci_event_callback_registration.callback = &packet_handler;
315     hci_add_event_handler(&hsp_hs_hci_event_callback_registration);
316 
317     rfcomm_register_service(packet_handler, rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
318 
319     hsp_hs_sco_packet_types = SCO_PACKET_TYPES_ALL;
320     hsp_hs_reset_state();
321 }
322 
323 void hsp_hs_deinit(void){
324     hsp_hs_reset_state();
325     hsp_hs_callback = NULL;
326     (void)memset(hsp_hs_remote, 0, 6);
327     (void)memset(&hsp_hs_hci_event_callback_registration, 0, sizeof(btstack_packet_callback_registration_t));
328     (void)memset(&hsp_hs_handle_sdp_client_query_request, 0, sizeof(btstack_context_callback_registration_t));
329 }
330 
331 static void hsp_hs_handle_start_sdp_client_query(void * context){
332     UNUSED(context);
333     if (hsp_state != HSP_W2_SEND_SDP_QUERY) return;
334 
335     hsp_state = HSP_W4_SDP_QUERY_COMPLETE;
336     log_info("Start SDP query %s, 0x%02x", bd_addr_to_str(hsp_hs_remote), BLUETOOTH_SERVICE_CLASS_HEADSET_AUDIO_GATEWAY_AG);
337     sdp_client_query_rfcomm_channel_and_name_for_service_class_uuid(&handle_query_rfcomm_event, hsp_hs_remote, BLUETOOTH_SERVICE_CLASS_HEADSET_AUDIO_GATEWAY_AG);
338 }
339 
340 void hsp_hs_connect(bd_addr_t bd_addr){
341     if (hsp_state != HSP_IDLE) return;
342 
343     (void)memcpy(hsp_hs_remote, bd_addr, 6);
344     hsp_state = HSP_W2_SEND_SDP_QUERY;
345     hsp_hs_handle_sdp_client_query_request.callback = &hsp_hs_handle_start_sdp_client_query;
346     // ignore ERROR_CODE_COMMAND_DISALLOWED because in that case, we already have requested an SDP callback
347     (void) sdp_client_register_query_callback(&hsp_hs_handle_sdp_client_query_request);
348 }
349 
350 void hsp_hs_disconnect(void){
351     hsp_hs_release_audio_connection();
352 
353     if (hsp_state < HSP_W4_RFCOMM_CONNECTED){
354         hsp_state = HSP_IDLE;
355         return;
356     }
357 
358     if (hsp_state == HSP_W4_RFCOMM_CONNECTED){
359         hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
360         return;
361     }
362 
363     hsp_hs_establish_audio_connection_triggered = 0;
364     rfcomm_disconnect(hsp_hs_rfcomm_cid);
365 }
366 
367 
368 void hsp_hs_establish_audio_connection(void){
369     switch (hsp_state){
370         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
371             hsp_hs_establish_audio_connection_triggered = 1;
372             hsp_state = HSP_W4_SCO_CONNECTED;
373             break;
374         case HSP_W4_RFCOMM_CONNECTED:
375             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
376             break;
377         default:
378             break;
379     }
380     hsp_run();
381 }
382 
383 void hsp_hs_release_audio_connection(void){
384     if (hsp_state >= HSP_W2_DISCONNECT_SCO) return;
385     if (hsp_state < HSP_AUDIO_CONNECTION_ESTABLISHED) return;
386     hsp_hs_release_audio_connection_triggered = 1;
387     hsp_run();
388 }
389 
390 void hsp_hs_set_microphone_gain(uint8_t gain){
391     if (gain >15) {
392         log_info("Gain must be in interval [0..15], it is given %d", gain);
393         return;
394     }
395     hsp_hs_microphone_gain = gain;
396     hsp_run();
397 }
398 
399 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
400 void hsp_hs_set_speaker_gain(uint8_t gain){
401     if (gain >15) {
402         log_info("Gain must be in interval [0..15], it is given %d", gain);
403         return;
404     }
405     hsp_hs_speaker_gain = gain;
406     hsp_run();
407 }
408 
409 static void hsp_run_handle_state(void){
410     switch (hsp_state){
411         case HSP_AUDIO_CONNECTION_ESTABLISHED:
412         case HSP_RFCOMM_CONNECTION_ESTABLISHED:
413 
414             if (hsp_hs_microphone_gain >= 0){
415                 if (!rfcomm_can_send_packet_now(hsp_hs_rfcomm_cid)) {
416                     rfcomm_request_can_send_now_event(hsp_hs_rfcomm_cid);
417                     return;
418                 }
419                 char buffer[20];
420                 snprintf(buffer, sizeof(buffer), "%s=%d\r",
421                          HSP_HS_MICROPHONE_GAIN, hsp_hs_microphone_gain);
422                 buffer[sizeof(buffer) - 1] = 0;
423                 hsp_hs_send_str_over_rfcomm(hsp_hs_rfcomm_cid, buffer);
424                 hsp_hs_microphone_gain = -1;
425                 break;
426             }
427 
428             if (hsp_hs_speaker_gain >= 0){
429                 if (!rfcomm_can_send_packet_now(hsp_hs_rfcomm_cid)) {
430                     rfcomm_request_can_send_now_event(hsp_hs_rfcomm_cid);
431                     return;
432                 }
433                 char buffer[20];
434                 snprintf(buffer, sizeof(buffer), "%s=%d\r",
435                          HSP_HS_SPEAKER_GAIN, hsp_hs_speaker_gain);
436                 buffer[sizeof(buffer) - 1] = 0;
437                 hsp_hs_send_str_over_rfcomm(hsp_hs_rfcomm_cid, buffer);
438                 hsp_hs_speaker_gain = -1;
439                 break;
440             }
441             break;
442         case HSP_W4_RFCOMM_DISCONNECTED:
443             rfcomm_disconnect(hsp_hs_rfcomm_cid);
444             break;
445         default:
446             break;
447     }
448 }
449 
450 static void hsp_run(void){
451 
452     if (hsp_hs_wait_ok) return;
453 
454     if (hsp_hs_accept_sco_connection && hci_can_send_command_packet_now()){
455 
456         bool eSCO = hsp_hs_accept_sco_connection == 2;
457         hsp_hs_accept_sco_connection = 0;
458 
459         log_info("HSP: sending hci_accept_connection_request.");
460 
461         // pick packet types based on SCO link type (SCO vs. eSCO)
462         uint16_t packet_types;
463         if (eSCO && hci_extended_sco_link_supported() && hci_remote_esco_supported(hsp_hs_rfcomm_handle)){
464             packet_types = 0x3F8;
465         } else {
466             packet_types = 0x0007;
467         }
468 
469         // packet type override
470         packet_types &= hsp_hs_sco_packet_types;
471 
472         // bits 6-9 are 'don't use'
473         packet_types ^= 0x03c0;
474 
475         uint16_t sco_voice_setting = hci_get_sco_voice_setting();
476 
477         log_info("HFP: sending hci_accept_connection_request, sco_voice_setting %02x", sco_voice_setting);
478         hci_send_cmd(&hci_accept_synchronous_connection, hsp_hs_remote, 8000, 8000, 0xffff, sco_voice_setting, 0xff, packet_types);
479         return;
480     }
481 
482     if (hsp_hs_release_audio_connection_triggered){
483         if (!rfcomm_can_send_packet_now(hsp_hs_rfcomm_cid)) {
484             rfcomm_request_can_send_now_event(hsp_hs_rfcomm_cid);
485             return;
486         }
487         hsp_hs_release_audio_connection_triggered = 0;
488         hsp_hs_wait_ok = 1;
489         hsp_hs_send_str_over_rfcomm(hsp_hs_rfcomm_cid, HSP_HS_AT_CKPD);
490         return;
491     }
492 
493     if (hsp_hs_establish_audio_connection_triggered){
494         if (!rfcomm_can_send_packet_now(hsp_hs_rfcomm_cid)) {
495             rfcomm_request_can_send_now_event(hsp_hs_rfcomm_cid);
496             return;
497         }
498         hsp_hs_establish_audio_connection_triggered = 0;
499         hsp_hs_wait_ok = 1;
500         hsp_hs_send_str_over_rfcomm(hsp_hs_rfcomm_cid, HSP_HS_AT_CKPD);
501         return;
502     }
503 
504     if (hsp_hs_send_button_press_triggered){
505         if (!rfcomm_can_send_packet_now(hsp_hs_rfcomm_cid)) {
506             rfcomm_request_can_send_now_event(hsp_hs_rfcomm_cid);
507             return;
508         }
509         hsp_hs_send_button_press_triggered = 0;
510         hsp_hs_wait_ok = 1;
511         hsp_hs_send_str_over_rfcomm(hsp_hs_rfcomm_cid, HSP_HS_AT_CKPD);
512         return;
513     }
514 
515 #ifdef ENABLE_RTK_PCM_WBS
516     if (hsp_hs_rtk_send_sco_config){
517         hsp_hs_rtk_send_sco_config = false;
518         log_info("RTK SCO: 16k + CVSD");
519         hci_send_cmd(&hci_rtk_configure_sco_routing, 0x81, 0x90, 0x00, 0x00, 0x1a, 0x0c, 0x0c, 0x00, 0x01);
520         return;
521     }
522 #endif
523 
524     hsp_run_handle_state();
525 }
526 
527 
528 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
529     UNUSED(channel);    // ok: no channel for HCI_EVENT_PACKET and only single active RFCOMM channel
530     if (packet_type == RFCOMM_DATA_PACKET){
531         // skip over leading newline
532         while ((size > 0) && ((packet[0] == '\n') || (packet[0] == '\r'))){
533             size--;
534             packet++;
535         }
536         if (strncmp((char *)packet, HSP_AG_RING, strlen(HSP_AG_RING)) == 0){
537             emit_event(HSP_SUBEVENT_RING);
538         } else if (strncmp((char *)packet, HSP_AG_OK, strlen(HSP_AG_OK)) == 0){
539             hsp_hs_wait_ok = 0;
540         } else if (strncmp((char *)packet, HSP_MICROPHONE_GAIN, strlen(HSP_MICROPHONE_GAIN)) == 0){
541             uint8_t gain = (uint8_t)btstack_atoi((char*)&packet[strlen(HSP_MICROPHONE_GAIN)]);
542             emit_event_with_value(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
543 
544         } else if (strncmp((char *)packet, HSP_SPEAKER_GAIN, strlen(HSP_SPEAKER_GAIN)) == 0){
545             uint8_t gain = (uint8_t)btstack_atoi((char*)&packet[strlen(HSP_SPEAKER_GAIN)]);
546             emit_event_with_value(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
547         } else {
548             if (!hsp_hs_callback) return;
549             // strip trailing newline
550             while ((size > 0) && ((packet[size-1] == '\n') || (packet[size-1] == '\r'))){
551                 size--;
552             }
553             // add trailing \0
554             packet[size] = 0;
555             // re-use incoming buffer to avoid reserving buffers/memcpy - ugly but efficient
556             uint8_t * event = packet - 6;
557             event[0] = HCI_EVENT_HSP_META;
558             event[1] = size + 4;
559             event[2] = HSP_SUBEVENT_AG_INDICATION;
560             little_endian_store_16(event, 3, hsp_hs_rfcomm_handle);
561             event[5] = size;
562             (*hsp_hs_callback)(HCI_EVENT_PACKET, 0, event, size+6);
563         }
564         hsp_run();
565         return;
566     }
567 
568     if (packet_type != HCI_EVENT_PACKET) return;
569 
570     uint8_t event = hci_event_packet_get_type(packet);
571     bd_addr_t event_addr;
572     uint16_t handle;
573     uint8_t status;
574 
575     switch (event) {
576         case HCI_EVENT_CONNECTION_REQUEST:
577             switch(hci_event_connection_request_get_link_type(packet)){
578                 case 0: //  SCO
579                 case 2: // eSCO
580                     hci_event_connection_request_get_bd_addr(packet, event_addr);
581                     if (bd_addr_cmp(event_addr, hsp_hs_remote) == 0){
582                         if (hci_event_connection_request_get_link_type(packet) == 2){
583                             hsp_hs_accept_sco_connection = 2;
584                         } else {
585                             hsp_hs_accept_sco_connection = 1;
586                         }
587                         log_info("hs_accept_sco_connection %u", hsp_hs_accept_sco_connection);
588                     }
589                     break;
590                 default:
591                     break;
592             }
593             break;
594 
595         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
596             if (hsp_state < HSP_RFCOMM_CONNECTION_ESTABLISHED) return;
597             hci_event_synchronous_connection_complete_get_bd_addr(packet, event_addr);
598             status                           = hci_event_synchronous_connection_complete_get_status(packet);
599             hsp_hs_sco_handle                = hci_event_synchronous_connection_complete_get_handle(packet);
600             uint8_t  link_type               = hci_event_synchronous_connection_complete_get_link_type(packet);
601             uint8_t  transmission_interval   = hci_event_synchronous_connection_complete_get_transmission_interval(packet);   // measured in slots
602             uint8_t  retransmission_interval = hci_event_synchronous_connection_complete_get_retransmission_interval(packet); // measured in slots
603             uint16_t rx_packet_length        = hci_event_synchronous_connection_complete_get_rx_packet_length(packet);        // measured in bytes
604             uint16_t tx_packet_length        = hci_event_synchronous_connection_complete_get_tx_packet_length(packet);        // measured in bytes
605 
606             if (status != 0){
607                 log_error("(e)SCO Connection failed, status %u", status);
608                 emit_event_audio_connected(status, hsp_hs_sco_handle);
609                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED ;
610                 break;
611             }
612 
613             switch (link_type){
614                 case 0x00:
615                     log_info("SCO Connection established.");
616                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
617                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
618                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
619                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
620                     break;
621                 case 0x02:
622                     log_info("eSCO Connection established.");
623                     break;
624                 default:
625                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
626                     break;
627             }
628             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
629                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", hsp_hs_sco_handle,
630                      bd_addr_to_str(event_addr), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length,
631                      hci_event_synchronous_connection_complete_get_air_mode(packet));
632 
633             hsp_state = HSP_AUDIO_CONNECTION_ESTABLISHED;
634             emit_event_audio_connected(status, hsp_hs_sco_handle);
635             break;
636         }
637 
638         case RFCOMM_EVENT_INCOMING_CONNECTION:
639             if (hsp_state != HSP_IDLE) return;
640             rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr);
641             hsp_hs_rfcomm_cid = rfcomm_event_incoming_connection_get_rfcomm_cid(packet);
642             log_info("RFCOMM channel %u requested for %s", rfcomm_event_incoming_connection_get_server_channel(packet), bd_addr_to_str(event_addr));
643             hsp_state = HSP_W4_RFCOMM_CONNECTED;
644             rfcomm_accept_connection(hsp_hs_rfcomm_cid);
645             break;
646 
647         case RFCOMM_EVENT_CHANNEL_OPENED:
648             if (hsp_state != HSP_W4_RFCOMM_CONNECTED) return;
649             status = rfcomm_event_channel_opened_get_status(packet);
650             if (status != ERROR_CODE_SUCCESS) {
651                 log_info("RFCOMM channel open failed, status %u", status);
652                 hsp_state = HSP_IDLE;
653                 hsp_hs_reset_state();
654             } else {
655                 rfcomm_event_channel_opened_get_bd_addr(packet, hsp_hs_remote);
656                 hsp_hs_rfcomm_handle = rfcomm_event_channel_opened_get_con_handle(packet);
657                 hsp_hs_rfcomm_cid    = rfcomm_event_channel_opened_get_rfcomm_cid(packet);
658                 rfcomm_event_channel_opened_get_bd_addr(packet, hsp_hs_remote);
659                 hsp_hs_rfcomm_mtu    = rfcomm_event_channel_opened_get_max_frame_size(packet);
660                 log_info("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, handle %02x", hsp_hs_rfcomm_cid, hsp_hs_rfcomm_mtu, hsp_hs_rfcomm_handle);
661                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
662 #ifdef ENABLE_RTK_PCM_WBS
663                 hsp_hs_rtk_send_sco_config = true;
664 #endif
665             }
666             emit_event_rfcomm_connected(status);
667             break;
668 
669         case RFCOMM_EVENT_CAN_SEND_NOW:
670             hsp_run();
671             break;
672 
673         case HCI_EVENT_DISCONNECTION_COMPLETE:
674             handle = hci_event_disconnection_complete_get_connection_handle(packet);
675             if (handle == hsp_hs_sco_handle){
676                 hci_con_handle_t sco_handle = hsp_hs_sco_handle;
677                 hsp_hs_sco_handle = HCI_CON_HANDLE_INVALID;
678                 hsp_state = HSP_RFCOMM_CONNECTION_ESTABLISHED;
679                 emit_event_audio_disconnected(sco_handle);
680                 break;
681             }
682             break;
683 
684         case RFCOMM_EVENT_CHANNEL_CLOSED:
685             hsp_state = HSP_IDLE;
686             hsp_hs_reset_state();
687             emit_event(HSP_SUBEVENT_RFCOMM_DISCONNECTION_COMPLETE);
688             break;
689 
690         default:
691             break;
692     }
693 
694     hsp_run();
695 }
696 
697 static void handle_query_rfcomm_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
698     UNUSED(packet_type);    // ok: handling own sdp events
699     UNUSED(channel);        // ok: no channel
700     UNUSED(size);           // ok: handling own sdp events
701 
702     switch (hci_event_packet_get_type(packet)){
703         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
704             hsp_hs_rfcomm_channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
705             log_info("** Service name: '%s', RFCOMM port %u", sdp_event_query_rfcomm_service_get_name(packet), hsp_hs_rfcomm_channel_nr);
706             break;
707         case SDP_EVENT_QUERY_COMPLETE:
708             if (hsp_hs_rfcomm_channel_nr > 0){
709                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
710                 log_info("HSP: SDP_QUERY_COMPLETE. RFCOMM create channel, addr %s, rfcomm channel nr %d", bd_addr_to_str(hsp_hs_remote), hsp_hs_rfcomm_channel_nr);
711                 rfcomm_create_channel(packet_handler, hsp_hs_remote, hsp_hs_rfcomm_channel_nr, NULL);
712                 break;
713             }
714             hsp_hs_reset_state();
715             log_info("Service not found, status %u.", sdp_event_query_complete_get_status(packet));
716             if (sdp_event_query_complete_get_status(packet)){
717                 emit_event_with_value(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE,
718                                       sdp_event_query_complete_get_status(packet));
719             } else {
720                 emit_event_with_value(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
721             }
722             break;
723         default:
724             break;
725     }
726 }
727 
728 void hsp_hs_send_button_press(void){
729     if ((hsp_state < HSP_RFCOMM_CONNECTION_ESTABLISHED) || (hsp_state >= HSP_W4_RFCOMM_DISCONNECTED)) return;
730     hsp_hs_send_button_press_triggered = 1;
731     hsp_run();
732 }
733 
734 void hsp_hs_set_sco_packet_types(uint16_t packet_types){
735     hsp_hs_sco_packet_types = packet_types;
736 }
737