xref: /btstack/src/hci.c (revision 549e6ebe45d4c41944b3fc57c21ca3aa6d12e575)
1 /*
2  * Copyright (C) 2009 by Matthias Ringwald
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  *
17  * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
20  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
21  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
24  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
27  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 /*
33  *  hci.c
34  *
35  *  Created by Matthias Ringwald on 4/29/09.
36  *
37  */
38 
39 #include "hci.h"
40 
41 #include <stdarg.h>
42 #include <string.h>
43 #include <stdio.h>
44 
45 #ifndef EMBEDDED
46 #include <unistd.h> // gethostbyname
47 #endif
48 
49 #include "debug.h"
50 #include "hci_dump.h"
51 
52 #include "../include/btstack/hci_cmds.h"
53 #include "../include/btstack/version.h"
54 
55 // temp
56 #include "l2cap.h"
57 
58 #define HCI_CONNECTION_TIMEOUT_MS 10000
59 
60 // the STACK is here
61 static hci_stack_t       hci_stack;
62 
63 /**
64  * get connection for a given handle
65  *
66  * @return connection OR NULL, if not found
67  */
68 hci_connection_t * connection_for_handle(hci_con_handle_t con_handle){
69     linked_item_t *it;
70     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
71         if ( ((hci_connection_t *) it)->con_handle == con_handle){
72             return (hci_connection_t *) it;
73         }
74     }
75     return NULL;
76 }
77 
78 static void hci_connection_timeout_handler(timer_source_t *timer){
79 #ifdef HAVE_TIME
80     hci_connection_t * connection = linked_item_get_user(&timer->item);
81     struct timeval tv;
82     gettimeofday(&tv, NULL);
83     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
84         // connections might be timed out
85         hci_emit_l2cap_check_timeout(connection);
86         run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
87     } else {
88         // next timeout check at
89         timer->timeout.tv_sec = connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000;
90     }
91     run_loop_add_timer(timer);
92 #endif
93 }
94 
95 static void hci_connection_timestamp(hci_connection_t *connection){
96 #ifdef HAVE_TIME
97     gettimeofday(&connection->timestamp, NULL);
98 #endif
99 }
100 
101 /**
102  * create connection for given address
103  *
104  * @return connection OR NULL, if not found
105  */
106 static hci_connection_t * create_connection_for_addr(bd_addr_t addr){
107     hci_connection_t * conn = malloc( sizeof(hci_connection_t) );
108     if (!conn) return NULL;
109     BD_ADDR_COPY(conn->address, addr);
110     conn->con_handle = 0xffff;
111     conn->authentication_flags = 0;
112 #ifdef HAVE_TIME
113     linked_item_set_user(&conn->timeout.item, conn);
114     conn->timeout.process = hci_connection_timeout_handler;
115     hci_connection_timestamp(conn);
116 #endif
117     conn->acl_recombination_length = 0;
118     conn->acl_recombination_pos = 0;
119     conn->num_acl_packets_sent = 0;
120     linked_list_add(&hci_stack.connections, (linked_item_t *) conn);
121     return conn;
122 }
123 
124 /**
125  * get connection for given address
126  *
127  * @return connection OR NULL, if not found
128  */
129 static hci_connection_t * connection_for_address(bd_addr_t address){
130     linked_item_t *it;
131     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
132         if ( ! BD_ADDR_CMP( ((hci_connection_t *) it)->address, address) ){
133             return (hci_connection_t *) it;
134         }
135     }
136     return NULL;
137 }
138 
139 /**
140  * add authentication flags and reset timer
141  */
142 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
143     bd_addr_t addr;
144     bt_flip_addr(addr, *(bd_addr_t *) bd_addr);
145     hci_connection_t * conn = connection_for_address(addr);
146     if (conn) {
147         conn->authentication_flags |= flags;
148         hci_connection_timestamp(conn);
149     }
150 }
151 
152 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
153     hci_connection_t * conn = connection_for_handle(handle);
154     if (!conn) return 0;
155     if (!conn->authentication_flags) return 0;
156     if (conn->authentication_flags & SENT_LINK_KEY_REPLY) return 0;
157     if (conn->authentication_flags & RECV_LINK_KEY_NOTIFICATION) return 0;
158     return 1;
159 }
160 
161 void hci_drop_link_key_for_bd_addr(bd_addr_t *addr){
162     if (hci_stack.remote_device_db) {
163         hci_stack.remote_device_db->delete_link_key(addr);
164     }
165 }
166 
167 
168 /**
169  * count connections
170  */
171 static int nr_hci_connections(void){
172     int count = 0;
173     linked_item_t *it;
174     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next, count++);
175     return count;
176 }
177 
178 /**
179  * Dummy handler called by HCI
180  */
181 static void dummy_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
182 }
183 
184 uint8_t hci_number_outgoing_packets(hci_con_handle_t handle){
185     hci_connection_t * connection = connection_for_handle(handle);
186     if (!connection) {
187         log_err("hci_number_outgoing_packets connectino for handle %u does not exist!\n", handle);
188         return 0;
189     }
190     return connection->num_acl_packets_sent;
191 }
192 
193 uint8_t hci_number_free_acl_slots(){
194     uint8_t free_slots = hci_stack.total_num_acl_packets;
195     linked_item_t *it;
196     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
197         hci_connection_t * connection = (hci_connection_t *) it;
198         if (free_slots < connection->num_acl_packets_sent) {
199             log_err("hci_number_free_acl_slots: sum of outgoing packets > total acl packets!\n");
200             return 0;
201         }
202         free_slots -= connection->num_acl_packets_sent;
203     }
204     return free_slots;
205 }
206 
207 uint16_t hci_max_acl_data_packet_length(){
208     return hci_stack.acl_data_packet_length;
209 }
210 
211 int hci_ready_to_send(hci_con_handle_t handle){
212     return hci_number_free_acl_slots() && hci_number_outgoing_packets(handle) < 2;
213 }
214 
215 int hci_send_acl_packet(uint8_t *packet, int size){
216 
217     // check for free places on BT module
218     if (!hci_number_free_acl_slots()) return -1;
219 
220     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
221     hci_connection_t *connection = connection_for_handle( con_handle);
222     if (!connection) return 0;
223     hci_connection_timestamp(connection);
224 
225     // count packet
226     connection->num_acl_packets_sent++;
227     // log_dbg("hci_send_acl_packet - handle %u, sent %u\n", connection->con_handle, connection->num_acl_packets_sent);
228 
229     // send packet - ignore errors
230     hci_stack.hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
231 
232     return 0;
233 }
234 
235 static void acl_handler(uint8_t *packet, int size){
236 
237     // get info
238     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
239     hci_connection_t *conn      = connection_for_handle(con_handle);
240     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
241     uint16_t acl_length         = READ_ACL_LENGTH(packet);
242 
243     // ignore non-registered handle
244     if (!conn){
245         log_err( "hci.c: acl_handler called with non-registered handle %u!\n" , con_handle);
246         return;
247     }
248 
249     // update idle timestamp
250     hci_connection_timestamp(conn);
251 
252     // handle different packet types
253     switch (acl_flags & 0x03) {
254 
255         case 0x01: // continuation fragment
256 
257             // sanity check
258             if (conn->acl_recombination_pos == 0) {
259                 log_err( "ACL Cont Fragment but no first fragment for handle 0x%02x\n", con_handle);
260                 return;
261             }
262 
263             // append fragment payload (header already stored)
264             memcpy(&conn->acl_recombination_buffer[conn->acl_recombination_pos], &packet[4], acl_length );
265             conn->acl_recombination_pos += acl_length;
266 
267             // log_err( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u\n",
268             //        acl_length, connection->acl_recombination_pos, connection->acl_recombination_length);
269 
270             // forward complete L2CAP packet if complete.
271             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
272 
273                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, conn->acl_recombination_buffer, conn->acl_recombination_pos);
274                 // reset recombination buffer
275                 conn->acl_recombination_length = 0;
276                 conn->acl_recombination_pos = 0;
277             }
278             break;
279 
280         case 0x02: { // first fragment
281 
282             // sanity check
283             if (conn->acl_recombination_pos) {
284                 log_err( "ACL First Fragment but data in buffer for handle 0x%02x\n", con_handle);
285                 return;
286             }
287 
288             // peek into L2CAP packet!
289             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
290 
291             // compare fragment size to L2CAP packet size
292             if (acl_length >= l2cap_length + 4){
293 
294                 // forward fragment as L2CAP packet
295                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, packet, acl_length + 4);
296 
297             } else {
298                 // store first fragment and tweak acl length for complete package
299                 memcpy(conn->acl_recombination_buffer, packet, acl_length + 4);
300                 conn->acl_recombination_pos    = acl_length + 4;
301                 conn->acl_recombination_length = l2cap_length;
302                 bt_store_16(conn->acl_recombination_buffer, 2, acl_length +4);
303                 // log_err( "ACL First Fragment: acl_len %u, l2cap_len %u\n", acl_length, l2cap_length);
304             }
305             break;
306 
307         }
308         default:
309             log_err( "hci.c: acl_handler called with invalid packet boundary flags %u\n", acl_flags & 0x03);
310             return;
311     }
312 
313     // execute main loop
314     hci_run();
315 }
316 
317 static void hci_shutdown_connection(hci_connection_t *conn){
318     log_dbg("Connection closed: handle %u, ", conn->con_handle);
319     print_bd_addr( conn->address );
320     log_dbg("\n");
321 
322     // cancel all l2cap connections
323     hci_emit_disconnection_complete(conn->con_handle, 0x16);    // terminated by local host
324 
325 #ifdef HAVE_TIME
326     run_loop_remove_timer(&conn->timeout);
327 #endif
328     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
329     free( conn );
330 
331     // now it's gone
332     hci_emit_nr_connections_changed();
333 }
334 
335 // avoid huge local variables
336 static device_name_t device_name;
337 static void event_handler(uint8_t *packet, int size){
338     bd_addr_t addr;
339     hci_con_handle_t handle;
340     hci_connection_t * conn;
341     int i;
342     link_key_t link_key;
343 
344     switch (packet[0]) {
345 
346         case HCI_EVENT_COMMAND_COMPLETE:
347             // get num cmd packets
348             // log_dbg("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u\n", hci_stack.num_cmd_packets, packet[2]);
349             hci_stack.num_cmd_packets = packet[2];
350 
351             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
352                 // from offset 5
353                 // status
354                 hci_stack.acl_data_packet_length = READ_BT_16(packet, 6);
355                 // ignore: SCO data packet len (8)
356                 hci_stack.total_num_acl_packets  = packet[9];
357                 // ignore: total num SCO packets
358                 if (hci_stack.state == HCI_STATE_INITIALIZING){
359                     log_dbg("hci_read_buffer_size: size %u, count %u\n", hci_stack.acl_data_packet_length, hci_stack.total_num_acl_packets);
360                 }
361             }
362             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
363                 hci_emit_discoverable_enabled(hci_stack.discoverable);
364             }
365             break;
366 
367         case HCI_EVENT_COMMAND_STATUS:
368             // get num cmd packets
369             // log_dbg("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u\n", hci_stack.num_cmd_packets, packet[3]);
370             hci_stack.num_cmd_packets = packet[3];
371             break;
372 
373         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:
374             for (i=0; i<packet[2];i++){
375                 handle = READ_BT_16(packet, 3 + 2*i);
376                 uint16_t num_packets = READ_BT_16(packet, 3 + packet[2]*2 + 2*i);
377                 conn = connection_for_handle(handle);
378                 if (!conn){
379                     log_err("hci_number_completed_packet lists unused con handle %u\n", handle);
380                     continue;
381                 }
382                 conn->num_acl_packets_sent -= num_packets;
383                 // log_dbg("hci_number_completed_packet %u processed for handle %u, outstanding %u\n", num_packets, handle, conn->num_acl_packets_sent);
384             }
385             break;
386 
387         case HCI_EVENT_CONNECTION_REQUEST:
388             bt_flip_addr(addr, &packet[2]);
389             // TODO: eval COD 8-10
390             uint8_t link_type = packet[11];
391             log_dbg("Connection_incoming: "); print_bd_addr(addr); log_dbg(", type %u\n", link_type);
392             if (link_type == 1) { // ACL
393                 conn = connection_for_address(addr);
394                 if (!conn) {
395                     conn = create_connection_for_addr(addr);
396                 }
397                 // TODO: check for malloc failure
398                 conn->state = ACCEPTED_CONNECTION_REQUEST;
399                 hci_send_cmd(&hci_accept_connection_request, addr, 1);
400             } else {
401                 // TODO: decline request
402             }
403             break;
404 
405         case HCI_EVENT_CONNECTION_COMPLETE:
406             // Connection management
407             bt_flip_addr(addr, &packet[5]);
408             log_dbg("Connection_complete (status=%u)", packet[2]); print_bd_addr(addr); log_dbg("\n");
409             conn = connection_for_address(addr);
410             if (conn) {
411                 if (!packet[2]){
412                     conn->state = OPEN;
413                     conn->con_handle = READ_BT_16(packet, 3);
414 
415 #ifdef HAVE_TIME
416                     gettimeofday(&conn->timestamp, NULL);
417                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
418                     run_loop_add_timer(&conn->timeout);
419 #endif
420                     log_dbg("New connection: handle %u, ", conn->con_handle);
421                     print_bd_addr( conn->address );
422                     log_dbg("\n");
423 
424                     hci_emit_nr_connections_changed();
425                 } else {
426                     // connection failed, remove entry
427                     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
428                     free( conn );
429 
430                     // if authentication error, also delete link key
431                     if (packet[2] == 0x05) {
432                         hci_drop_link_key_for_bd_addr(&addr);
433                     }
434                 }
435             }
436             break;
437 
438         case HCI_EVENT_LINK_KEY_REQUEST:
439             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
440             if (!hci_stack.remote_device_db) break;
441             bt_flip_addr(addr, &packet[2]);
442             if ( hci_stack.remote_device_db->get_link_key( &addr, &link_key)){
443                 hci_send_cmd(&hci_link_key_request_reply, &addr, &link_key);
444             } else {
445                 hci_send_cmd(&hci_link_key_request_negative_reply, &addr);
446             }
447             // request already answered
448             return;
449 
450         case HCI_EVENT_LINK_KEY_NOTIFICATION:
451             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_NOTIFICATION);
452             if (!hci_stack.remote_device_db) break;
453             bt_flip_addr(addr, &packet[2]);
454             hci_stack.remote_device_db->put_link_key(&addr, (link_key_t *) &packet[8]);
455             // still forward event to allow dismiss of pairing dialog
456             break;
457 
458         case HCI_EVENT_PIN_CODE_REQUEST:
459             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_PIN_CODE_REQUEST);
460             break;
461 
462         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
463             if (!hci_stack.remote_device_db) break;
464             if (packet[2]) break; // status not ok
465             bt_flip_addr(addr, &packet[3]);
466             bzero(&device_name, sizeof(device_name_t));
467             strncpy((char*) device_name, (char*) &packet[9], 248);
468             hci_stack.remote_device_db->put_name(&addr, &device_name);
469             break;
470 
471         case HCI_EVENT_INQUIRY_RESULT:
472         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
473             if (!hci_stack.remote_device_db) break;
474             // first send inq result packet
475             hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
476             // then send cached remote names
477             for (i=0; i<packet[2];i++){
478                 bt_flip_addr(addr, &packet[3+i*6]);
479                 if (hci_stack.remote_device_db->get_name(&addr, &device_name)){
480                     hci_emit_remote_name_cached(&addr, &device_name);
481                 }
482             }
483             return;
484 
485         case HCI_EVENT_DISCONNECTION_COMPLETE:
486             if (!packet[2]){
487                 handle = READ_BT_16(packet, 3);
488                 hci_connection_t * conn = connection_for_handle(handle);
489                 if (conn) {
490                     hci_shutdown_connection(conn);
491                 }
492             }
493             break;
494 
495         default:
496             break;
497     }
498 
499     // handle BT initialization
500     if (hci_stack.state == HCI_STATE_INITIALIZING){
501         // handle H4 synchronization loss on restart
502         // if (hci_stack.substate == 1 && packet[0] == HCI_EVENT_HARDWARE_ERROR){
503         //    hci_stack.substate = 0;
504         // }
505         // handle normal init sequence
506         if (hci_stack.substate % 2){
507             // odd: waiting for event
508             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE){
509                 hci_stack.substate++;
510             }
511         }
512     }
513 
514     // help with BT sleep
515     if (hci_stack.state == HCI_STATE_FALLING_ASLEEP
516         && hci_stack.substate == 1
517         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
518         hci_stack.substate++;
519     }
520 
521     hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
522 
523 	// execute main loop
524 	hci_run();
525 }
526 
527 void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
528     switch (packet_type) {
529         case HCI_EVENT_PACKET:
530             event_handler(packet, size);
531             break;
532         case HCI_ACL_DATA_PACKET:
533             acl_handler(packet, size);
534             break;
535         default:
536             break;
537     }
538 }
539 
540 /** Register HCI packet handlers */
541 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
542     hci_stack.packet_handler = handler;
543 }
544 
545 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t * remote_device_db){
546 
547     // reference to use transport layer implementation
548     hci_stack.hci_transport = transport;
549 
550     // references to used control implementation
551     hci_stack.control = control;
552 
553     // reference to used config
554     hci_stack.config = config;
555 
556     // no connections yet
557     hci_stack.connections = NULL;
558     hci_stack.discoverable = 0;
559 
560     // empty cmd buffer
561     hci_stack.hci_cmd_buffer = malloc(3+255);
562 
563     // higher level handler
564     hci_stack.packet_handler = dummy_handler;
565 
566     // store and open remote device db
567     hci_stack.remote_device_db = remote_device_db;
568     if (hci_stack.remote_device_db) {
569         hci_stack.remote_device_db->open();
570     }
571 
572     // register packet handlers with transport
573     transport->register_packet_handler(&packet_handler);
574 }
575 
576 void hci_close(){
577     // close remote device db
578     if (hci_stack.remote_device_db) {
579         hci_stack.remote_device_db->close();
580     }
581 }
582 
583 // State-Module-Driver overview
584 // state                    module  low-level
585 // HCI_STATE_OFF             off      close
586 // HCI_STATE_INITIALIZING,   on       open
587 // HCI_STATE_WORKING,        on       open
588 // HCI_STATE_HALTING,        on       open
589 // HCI_STATE_SLEEPING,    off/sleep   close
590 // HCI_STATE_FALLING_ASLEEP  on       open
591 
592 static int hci_power_control_on(void){
593 
594     // power on
595     int err = 0;
596     if (hci_stack.control && hci_stack.control->on){
597         err = (*hci_stack.control->on)(hci_stack.config);
598     }
599     if (err){
600         log_err( "POWER_ON failed\n");
601         hci_emit_hci_open_failed();
602         return err;
603     }
604 
605     // open low-level device
606     err = hci_stack.hci_transport->open(hci_stack.config);
607     if (err){
608         log_err( "HCI_INIT failed, turning Bluetooth off again\n");
609         if (hci_stack.control && hci_stack.control->off){
610             (*hci_stack.control->off)(hci_stack.config);
611         }
612         hci_emit_hci_open_failed();
613         return err;
614     }
615     return 0;
616 }
617 
618 static void hci_power_control_off(void){
619 
620     log_dbg("hci_power_control_off\n");
621 
622     // close low-level device
623     hci_stack.hci_transport->close(hci_stack.config);
624 
625     log_dbg("hci_power_control_off - hci_transport closed\n");
626 
627     // power off
628     if (hci_stack.control && hci_stack.control->off){
629         (*hci_stack.control->off)(hci_stack.config);
630     }
631 
632     log_dbg("hci_power_control_off - control closed\n");
633 
634     hci_stack.state = HCI_STATE_OFF;
635 }
636 
637 static void hci_power_control_sleep(void){
638 
639     log_dbg("hci_power_control_sleep\n");
640 
641 #if 0
642     // don't close serial port during sleep
643 
644     // close low-level device
645     hci_stack.hci_transport->close(hci_stack.config);
646 #endif
647 
648     // sleep mode
649     if (hci_stack.control && hci_stack.control->sleep){
650         (*hci_stack.control->sleep)(hci_stack.config);
651     }
652 
653     hci_stack.state = HCI_STATE_SLEEPING;
654 }
655 
656 static int hci_power_control_wake(void){
657 
658     log_dbg("hci_power_control_wake\n");
659 
660     // wake on
661     if (hci_stack.control && hci_stack.control->wake){
662         (*hci_stack.control->wake)(hci_stack.config);
663     }
664 
665 #if 0
666     // open low-level device
667     int err = hci_stack.hci_transport->open(hci_stack.config);
668     if (err){
669         log_err( "HCI_INIT failed, turning Bluetooth off again\n");
670         if (hci_stack.control && hci_stack.control->off){
671             (*hci_stack.control->off)(hci_stack.config);
672         }
673         hci_emit_hci_open_failed();
674         return err;
675     }
676 #endif
677 
678     return 0;
679 }
680 
681 
682 int hci_power_control(HCI_POWER_MODE power_mode){
683 
684     log_dbg("hci_power_control: %u, current mode %u\n", power_mode, hci_stack.state);
685 
686     int err = 0;
687     switch (hci_stack.state){
688 
689         case HCI_STATE_OFF:
690             switch (power_mode){
691                 case HCI_POWER_ON:
692                     err = hci_power_control_on();
693                     if (err) return err;
694                     // set up state machine
695                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
696                     hci_stack.state = HCI_STATE_INITIALIZING;
697                     hci_stack.substate = 0;
698                     break;
699                 case HCI_POWER_OFF:
700                     // do nothing
701                     break;
702                 case HCI_POWER_SLEEP:
703                     // do nothing (with SLEEP == OFF)
704                     break;
705             }
706             break;
707 
708         case HCI_STATE_INITIALIZING:
709             switch (power_mode){
710                 case HCI_POWER_ON:
711                     // do nothing
712                     break;
713                 case HCI_POWER_OFF:
714                     // no connections yet, just turn it off
715                     hci_power_control_off();
716                     break;
717                 case HCI_POWER_SLEEP:
718                     // no connections yet, just turn it off
719                     hci_power_control_sleep();
720                     break;
721             }
722             break;
723 
724         case HCI_STATE_WORKING:
725             switch (power_mode){
726                 case HCI_POWER_ON:
727                     // do nothing
728                     break;
729                 case HCI_POWER_OFF:
730                     // see hci_run
731                     hci_stack.state = HCI_STATE_HALTING;
732                     break;
733                 case HCI_POWER_SLEEP:
734                     // see hci_run
735                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
736                     hci_stack.substate = 0;
737                     break;
738             }
739             break;
740 
741         case HCI_STATE_HALTING:
742             switch (power_mode){
743                 case HCI_POWER_ON:
744                     // set up state machine
745                     hci_stack.state = HCI_STATE_INITIALIZING;
746                     hci_stack.substate = 0;
747                     break;
748                 case HCI_POWER_OFF:
749                     // do nothing
750                     break;
751                 case HCI_POWER_SLEEP:
752                     // see hci_run
753                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
754                     hci_stack.substate = 0;
755                     break;
756             }
757             break;
758 
759         case HCI_STATE_FALLING_ASLEEP:
760             switch (power_mode){
761                 case HCI_POWER_ON:
762                     // set up state machine
763                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
764                     hci_stack.state = HCI_STATE_INITIALIZING;
765                     hci_stack.substate = 0;
766                     break;
767                 case HCI_POWER_OFF:
768                     // see hci_run
769                     hci_stack.state = HCI_STATE_HALTING;
770                     break;
771                 case HCI_POWER_SLEEP:
772                     // do nothing
773                     break;
774             }
775             break;
776 
777         case HCI_STATE_SLEEPING:
778             switch (power_mode){
779                 case HCI_POWER_ON:
780                     err = hci_power_control_wake();
781                     if (err) return err;
782                     // set up state machine
783                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
784                     hci_stack.state = HCI_STATE_INITIALIZING;
785                     hci_stack.substate = 0;
786                     break;
787                 case HCI_POWER_OFF:
788                     hci_stack.state = HCI_STATE_HALTING;
789                     break;
790                 case HCI_POWER_SLEEP:
791                     // do nothing
792                     break;
793             }
794             break;
795     }
796 
797     // create internal event
798 	hci_emit_state();
799 
800 	// trigger next/first action
801 	hci_run();
802 
803     return 0;
804 }
805 
806 void hci_discoverable_control(uint8_t enable){
807     if (enable) enable = 1; // normalize argument
808 
809     if (hci_stack.discoverable == enable){
810         hci_emit_discoverable_enabled(hci_stack.discoverable);
811         return;
812     }
813 
814     hci_send_cmd(&hci_write_scan_enable, 2 | enable); // 1 = inq scan, 2 = page scan
815     hci_stack.discoverable = enable;
816 }
817 
818 void hci_run(){
819 
820     if (hci_stack.num_cmd_packets == 0) {
821         // cannot send command yet
822         return;
823     }
824 
825     hci_connection_t * connection;
826 
827     switch (hci_stack.state){
828         case HCI_STATE_INITIALIZING:
829             if (hci_stack.substate % 2) {
830                 // odd: waiting for command completion
831                 return;
832             }
833             switch (hci_stack.substate >> 1){
834                 case 0: // RESET
835                     hci_send_cmd(&hci_reset);
836                     if (hci_stack.config == 0 || ((hci_uart_config_t *)hci_stack.config)->baudrate_main == 0){
837                         // skip baud change
838                         hci_stack.substate = 4; // >> 1 = 2
839                     }
840                     break;
841                 case 1: // SEND BAUD CHANGE
842                     hci_stack.control->baudrate_cmd(hci_stack.config, ((hci_uart_config_t *)hci_stack.config)->baudrate_main, hci_stack.hci_cmd_buffer);
843                     hci_send_cmd_packet(hci_stack.hci_cmd_buffer, 3 + hci_stack.hci_cmd_buffer[2]);
844                     break;
845                 case 2: // LOCAL BAUD CHANGE
846                     hci_stack.hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack.config)->baudrate_main);
847                     hci_stack.substate += 2;
848                     // break missing here for fall through
849 
850                 case 3:
851                     // custom initialization
852                     if (hci_stack.control && hci_stack.control->next_command){
853                         uint8_t * cmd = (*hci_stack.control->next_command)(hci_stack.config);
854                         if (cmd) {
855                             int size = 3 + cmd[2];
856                             hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, cmd, size);
857                             hci_stack.substate = 4; // more init commands
858                             break;
859                         }
860                         printf("hci_run: init script done\n\r");
861                     }
862                     // otherwise continue
863 					hci_send_cmd(&hci_read_bd_addr);
864 					break;
865 				case 4:
866 					hci_send_cmd(&hci_read_buffer_size);
867 					break;
868                 case 5:
869                     // ca. 15 sec
870                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
871                     break;
872 				case 6:
873 					hci_send_cmd(&hci_write_scan_enable, 2 | hci_stack.discoverable); // page scan
874 					break;
875                 case 7:
876 #ifndef EMBEDDED
877                 {
878                     char hostname[30];
879                     gethostname(hostname, 30);
880                     hostname[29] = '\0';
881                     hci_send_cmd(&hci_write_local_name, hostname);
882                     break;
883                 }
884                 case 8:
885 #ifdef USE_BLUETOOL
886                     hci_send_cmd(&hci_write_class_of_device, 0x007a020c); // Smartphone
887                     break;
888 
889                 case 9:
890 #endif
891 #endif
892                     // done.
893                     hci_stack.state = HCI_STATE_WORKING;
894                     hci_emit_state();
895                     break;
896                 default:
897                     break;
898             }
899             hci_stack.substate++;
900             break;
901 
902         case HCI_STATE_HALTING:
903 
904             log_dbg("HCI_STATE_HALTING\n");
905             // close all open connections
906             connection =  (hci_connection_t *) hci_stack.connections;
907             if (connection){
908                 log_dbg("HCI_STATE_HALTING, connection %lu, handle %u\n", (uintptr_t) connection, connection->con_handle);
909                 // send disconnect
910                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
911 
912                 // send disconnected event right away - causes higher layer connections to get closed, too.
913                 hci_shutdown_connection(connection);
914                 return;
915             }
916             log_dbg("HCI_STATE_HALTING, calling off\n");
917 
918             // switch mode
919             hci_power_control_off();
920 
921             log_dbg("HCI_STATE_HALTING, emitting state\n");
922             hci_emit_state();
923             log_dbg("HCI_STATE_HALTING, done\n");
924             break;
925 
926         case HCI_STATE_FALLING_ASLEEP:
927             switch(hci_stack.substate) {
928                 case 0:
929                     log_dbg("HCI_STATE_FALLING_ASLEEP\n");
930                     // close all open connections
931                     connection =  (hci_connection_t *) hci_stack.connections;
932                     if (connection){
933                         log_dbg("HCI_STATE_FALLING_ASLEEP, connection %lu, handle %u\n", (uintptr_t) connection, connection->con_handle);
934                         // send disconnect
935                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
936 
937                         // send disconnected event right away - causes higher layer connections to get closed, too.
938                         hci_shutdown_connection(connection);
939                         return;
940                     }
941 
942                     log_dbg("HCI_STATE_HALTING, disabling inq & page scans\n");
943 
944                     // disable page and inquiry scan
945                     hci_send_cmd(&hci_write_scan_enable, 0); // none
946 
947                     // continue in next sub state
948                     hci_stack.substate++;
949                     break;
950                 case 1:
951                     // wait for command complete "hci_write_scan_enable" in event_handler();
952                     break;
953                 case 2:
954                     log_dbg("HCI_STATE_HALTING, calling sleep\n");
955                     // switch mode
956                     hci_power_control_sleep();  // changes hci_stack.state to SLEEP
957                     hci_emit_state();
958                 default:
959                     break;
960             }
961             break;
962 
963         default:
964             break;
965     }
966 }
967 
968 int hci_send_cmd_packet(uint8_t *packet, int size){
969     bd_addr_t addr;
970     hci_connection_t * conn;
971     // house-keeping
972 
973     // create_connection?
974     if (IS_COMMAND(packet, hci_create_connection)){
975         bt_flip_addr(addr, &packet[3]);
976         log_dbg("Create_connection to "); print_bd_addr(addr); log_dbg("\n");
977         conn = connection_for_address(addr);
978         if (conn) {
979             // if connection exists
980             if (conn->state == OPEN) {
981                 // if OPEN, emit connection complete command
982                 hci_emit_connection_complete(conn);
983             }
984             //    otherwise, just ignore
985             return 0; // don't sent packet to controller
986 
987         } else{
988             conn = create_connection_for_addr(addr);
989             if (conn){
990                 //    create connection struct and register, state = SENT_CREATE_CONNECTION
991                 conn->state = SENT_CREATE_CONNECTION;
992             }
993         }
994     }
995 
996     if (IS_COMMAND(packet, hci_link_key_request_reply)){
997         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
998     }
999     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
1000         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
1001     }
1002     if (IS_COMMAND(packet, hci_pin_code_request_reply)){
1003         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_REPLY);
1004     }
1005     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)){
1006         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_NEGATIVE_REPLY);
1007     }
1008 
1009     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
1010         if (hci_stack.remote_device_db){
1011             bt_flip_addr(addr, &packet[3]);
1012             hci_stack.remote_device_db->delete_link_key(&addr);
1013         }
1014     }
1015 
1016     hci_stack.num_cmd_packets--;
1017     return hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
1018 }
1019 
1020 /**
1021  * pre: numcmds >= 0 - it's allowed to send a command to the controller
1022  */
1023 int hci_send_cmd(const hci_cmd_t *cmd, ...){
1024     va_list argptr;
1025     va_start(argptr, cmd);
1026     uint8_t * hci_cmd_buffer = hci_stack.hci_cmd_buffer;
1027     uint16_t size = hci_create_cmd_internal(hci_stack.hci_cmd_buffer, cmd, argptr);
1028     va_end(argptr);
1029     return hci_send_cmd_packet(hci_cmd_buffer, size);
1030 }
1031 
1032 // Create various non-HCI events.
1033 // TODO: generalize, use table similar to hci_create_command
1034 
1035 void hci_emit_state(){
1036     uint8_t len = 3;
1037     uint8_t event[len];
1038     event[0] = BTSTACK_EVENT_STATE;
1039     event[1] = len - 3;
1040     event[2] = hci_stack.state;
1041     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1042     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1043 }
1044 
1045 void hci_emit_connection_complete(hci_connection_t *conn){
1046     uint8_t len = 13;
1047     uint8_t event[len];
1048     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
1049     event[1] = len - 3;
1050     event[2] = 0; // status = OK
1051     bt_store_16(event, 3, conn->con_handle);
1052     bt_flip_addr(&event[5], conn->address);
1053     event[11] = 1; // ACL connection
1054     event[12] = 0; // encryption disabled
1055     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1056     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1057 }
1058 
1059 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
1060     uint8_t len = 6;
1061     uint8_t event[len];
1062     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
1063     event[1] = len - 3;
1064     event[2] = 0; // status = OK
1065     bt_store_16(event, 3, handle);
1066     event[5] = reason;
1067     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1068     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1069 }
1070 
1071 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
1072     uint8_t len = 4;
1073     uint8_t event[len];
1074     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
1075     event[1] = len - 2;
1076     bt_store_16(event, 2, conn->con_handle);
1077     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1078     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1079 }
1080 
1081 void hci_emit_nr_connections_changed(){
1082     uint8_t len = 3;
1083     uint8_t event[len];
1084     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
1085     event[1] = len - 2;
1086     event[2] = nr_hci_connections();
1087     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1088     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1089 }
1090 
1091 void hci_emit_hci_open_failed(){
1092     uint8_t len = 2;
1093     uint8_t event[len];
1094     event[0] = BTSTACK_EVENT_POWERON_FAILED;
1095     event[1] = len - 2;
1096     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1097     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1098 }
1099 
1100 
1101 void hci_emit_btstack_version() {
1102     uint8_t len = 6;
1103     uint8_t event[len];
1104     event[0] = BTSTACK_EVENT_VERSION;
1105     event[1] = len - 2;
1106     event[len++] = BTSTACK_MAJOR;
1107     event[len++] = BTSTACK_MINOR;
1108     bt_store_16(event, len, BTSTACK_REVISION);
1109     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1110     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1111 }
1112 
1113 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
1114     uint8_t len = 3;
1115     uint8_t event[len];
1116     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
1117     event[1] = len - 2;
1118     event[2] = enabled;
1119     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1120     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1121 }
1122 
1123 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name){
1124     uint16_t len = 2+1+6+248;
1125     uint8_t event[len];
1126     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
1127     event[1] = len - 2;
1128     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
1129     bt_flip_addr(&event[3], *addr);
1130     memcpy(&event[9], name, 248);
1131     hci_dump_packet(HCI_EVENT_PACKET, 0, event, len);
1132     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1133 }
1134 
1135 void hci_emit_discoverable_enabled(uint8_t enabled){
1136     uint8_t len = 3;
1137     uint8_t event[len];
1138     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
1139     event[1] = len - 2;
1140     event[2] = enabled;
1141     hci_dump_packet( HCI_EVENT_PACKET, 0, event, len);
1142     hci_stack.packet_handler(HCI_EVENT_PACKET, event, len);
1143 }
1144