summaryrefslogtreecommitdiffstats
path: root/main/bte_main.c
blob: 688deca858d96025145c2e9a38f92a8d722f9c6e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
/******************************************************************************
 *
 *  Copyright (C) 2009-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  Filename:      bte_main.c
 *
 *  Description:   Contains BTE core stack initialization and shutdown code
 *
 ******************************************************************************/
#include <fcntl.h>
#include <stdlib.h>
#include <assert.h>
#include <signal.h>
#include <time.h>
#include <hardware/bluetooth.h>

#include "gki.h"
#include "bd.h"
#include "btu.h"
#include "bte.h"
#include "bta_api.h"
#include "bt_utils.h"
#include "bt_hci_bdroid.h"

/*******************************************************************************
**  Constants & Macros
*******************************************************************************/

/* Run-time configuration file */
#ifndef BTE_STACK_CONF_FILE
#define BTE_STACK_CONF_FILE "/etc/bluetooth/bt_stack.conf"
#endif

/* if not specified in .txt file then use this as default  */
#ifndef HCI_LOGGING_FILENAME
#define HCI_LOGGING_FILENAME  "/data/misc/bluedroid/btsnoop_hci.log"
#endif

/* Stack preload process timeout period  */
#ifndef PRELOAD_START_TIMEOUT_MS
#define PRELOAD_START_TIMEOUT_MS 3000  // 3 seconds
#endif

/* Stack preload process maximum retry attempts  */
#ifndef PRELOAD_MAX_RETRY_ATTEMPTS
#define PRELOAD_MAX_RETRY_ATTEMPTS 0
#endif

/*******************************************************************************
**  Local type definitions
*******************************************************************************/
/* Preload retry control block */
typedef struct
{
    int     retry_counts;
    BOOLEAN timer_created;
    timer_t timer_id;
} bt_preload_retry_cb_t;

/******************************************************************************
**  Variables
******************************************************************************/
BOOLEAN hci_logging_enabled = FALSE;    /* by default, turn hci log off */
BOOLEAN hci_logging_config = FALSE;    /* configured from bluetooth framework */
char hci_logfile[256] = HCI_LOGGING_FILENAME;


/*******************************************************************************
**  Static variables
*******************************************************************************/
static bt_hc_interface_t *bt_hc_if=NULL;
static const bt_hc_callbacks_t hc_callbacks;
static BOOLEAN lpm_enabled = FALSE;
static bt_preload_retry_cb_t preload_retry_cb;

/*******************************************************************************
**  Static functions
*******************************************************************************/
static void bte_main_in_hw_init(void);
static void bte_hci_enable(void);
static void bte_hci_disable(void);
static void preload_start_wait_timer(void);
static void preload_stop_wait_timer(void);

/*******************************************************************************
**  Externs
*******************************************************************************/
BTU_API extern UINT32 btu_task (UINT32 param);
BTU_API extern void BTE_Init (void);
BT_API extern void BTE_LoadStack(void);
BT_API void BTE_UnloadStack(void);
extern void scru_flip_bda (BD_ADDR dst, const BD_ADDR src);
extern void bte_load_conf(const char *p_path);
extern bt_bdaddr_t btif_local_bd_addr;


/*******************************************************************************
**                        System Task Configuration
*******************************************************************************/

/* bluetooth protocol stack (BTU) task */
#ifndef BTE_BTU_STACK_SIZE
#define BTE_BTU_STACK_SIZE       0//0x2000         /* In bytes */
#endif
#define BTE_BTU_TASK_STR        ((INT8 *) "BTU")
UINT32 bte_btu_stack[(BTE_BTU_STACK_SIZE + 3) / 4];

/******************************************************************************
**
** Function         bte_main_in_hw_init
**
** Description      Internal helper function for chip hardware init
**
** Returns          None
**
******************************************************************************/
static void bte_main_in_hw_init(void)
{
    if ( (bt_hc_if = (bt_hc_interface_t *) bt_hc_get_interface()) \
         == NULL)
    {
        APPL_TRACE_ERROR("!!! Failed to get BtHostControllerInterface !!!");
    }

    memset(&preload_retry_cb, 0, sizeof(bt_preload_retry_cb_t));
}

/******************************************************************************
**
** Function         bte_main_boot_entry
**
** Description      BTE MAIN API - Entry point for BTE chip/stack initialization
**
** Returns          None
**
******************************************************************************/
void bte_main_boot_entry(void)
{
    /* initialize OS */
    GKI_init();

    bte_main_in_hw_init();

    bte_load_conf(BTE_STACK_CONF_FILE);

#if (BTTRC_INCLUDED == TRUE)
    /* Initialize trace feature */
    BTTRC_TraceInit(MAX_TRACE_RAM_SIZE, &BTE_TraceLogBuf[0], BTTRC_METHOD_RAM);
#endif
}

/******************************************************************************
**
** Function         bte_main_shutdown
**
** Description      BTE MAIN API - Shutdown code for BTE chip/stack
**
** Returns          None
**
******************************************************************************/
void bte_main_shutdown()
{
    GKI_shutdown();
}

/******************************************************************************
**
** Function         bte_main_enable
**
** Description      BTE MAIN API - Creates all the BTE tasks. Should be called
**                  part of the Bluetooth stack enable sequence
**
** Returns          None
**
******************************************************************************/
void bte_main_enable()
{
    APPL_TRACE_DEBUG("%s", __FUNCTION__);

    /* Initialize BTE control block */
    BTE_Init();

    lpm_enabled = FALSE;

    GKI_create_task((TASKPTR)btu_task, BTU_TASK, BTE_BTU_TASK_STR,
                    (UINT16 *) ((UINT8 *)bte_btu_stack + BTE_BTU_STACK_SIZE),
                    sizeof(bte_btu_stack));

    bte_hci_enable();

    GKI_run(0);
}

/******************************************************************************
**
** Function         bte_main_disable
**
** Description      BTE MAIN API - Destroys all the BTE tasks. Should be called
**                  part of the Bluetooth stack disable sequence
**
** Returns          None
**
******************************************************************************/
void bte_main_disable(void)
{
    APPL_TRACE_DEBUG("%s", __FUNCTION__);

    preload_stop_wait_timer();
    bte_hci_disable();
    GKI_destroy_task(BTU_TASK);
}

/******************************************************************************
**
** Function         bte_main_config_hci_logging
**
** Description      enable or disable HIC snoop logging
**
** Returns          None
**
******************************************************************************/
void bte_main_config_hci_logging(BOOLEAN enable, BOOLEAN bt_disabled)
{
    int old = (hci_logging_enabled == TRUE) || (hci_logging_config == TRUE);
    int new;

    if (enable) {
        hci_logging_config = TRUE;
    } else {
        hci_logging_config = FALSE;
    }

    new = (hci_logging_enabled == TRUE) || (hci_logging_config == TRUE);

    if ((old == new) || bt_disabled || (bt_hc_if == NULL)) {
        return;
    }

    bt_hc_if->logging(new ? BT_HC_LOGGING_ON : BT_HC_LOGGING_OFF, hci_logfile);
}

/******************************************************************************
**
** Function         bte_hci_enable
**
** Description      Enable HCI & Vendor modules
**
** Returns          None
**
******************************************************************************/
static void bte_hci_enable(void)
{
    APPL_TRACE_DEBUG("%s", __FUNCTION__);

    preload_start_wait_timer();

    if (bt_hc_if)
    {
        int result = bt_hc_if->init(&hc_callbacks, btif_local_bd_addr.address);
        APPL_TRACE_EVENT("libbt-hci init returns %d", result);

        assert(result == BT_HC_STATUS_SUCCESS);

        if (hci_logging_enabled == TRUE || hci_logging_config == TRUE)
            bt_hc_if->logging(BT_HC_LOGGING_ON, hci_logfile);

#if (defined (BT_CLEAN_TURN_ON_DISABLED) && BT_CLEAN_TURN_ON_DISABLED == TRUE)
        APPL_TRACE_DEBUG("%s  Not Turninig Off the BT before Turninig ON", __FUNCTION__);

        /* Do not power off the chip before powering on  if BT_CLEAN_TURN_ON_DISABLED flag
         is defined and set to TRUE to avoid below mentioned issue.

         Wingray kernel driver maintains a combined  counter to keep track of
         BT-Wifi state. Invoking  set_power(BT_HC_CHIP_PWR_OFF) when the BT is already
         in OFF state causes this counter to be incorrectly decremented and results in undesired
         behavior of the chip.

         This is only a workaround and when the issue is fixed in the kernel this work around
         should be removed. */
#else
        /* toggle chip power to ensure we will reset chip in case
           a previous stack shutdown wasn't completed gracefully */
        bt_hc_if->set_power(BT_HC_CHIP_PWR_OFF);
#endif
        bt_hc_if->set_power(BT_HC_CHIP_PWR_ON);

        bt_hc_if->preload(NULL);
    }
}

/******************************************************************************
**
** Function         bte_hci_disable
**
** Description      Disable HCI & Vendor modules
**
** Returns          None
**
******************************************************************************/
static void bte_hci_disable(void)
{
    APPL_TRACE_DEBUG("%s", __FUNCTION__);

    if (bt_hc_if)
    {
        if (hci_logging_enabled == TRUE ||  hci_logging_config == TRUE)
            bt_hc_if->logging(BT_HC_LOGGING_OFF, hci_logfile);
        bt_hc_if->cleanup();
    }
}

/*******************************************************************************
**
** Function        preload_wait_timeout
**
** Description     Timeout thread of preload watchdog timer
**
** Returns         None
**
*******************************************************************************/
static void preload_wait_timeout(union sigval arg)
{
    UNUSED(arg);

    APPL_TRACE_ERROR("...preload_wait_timeout (retried:%d/max-retry:%d)...",
                        preload_retry_cb.retry_counts,
                        PRELOAD_MAX_RETRY_ATTEMPTS);

    if (preload_retry_cb.retry_counts++ < PRELOAD_MAX_RETRY_ATTEMPTS)
    {
        bte_hci_disable();
        GKI_delay(100);
        bte_hci_enable();
    }
    else
    {
        /* Notify BTIF_TASK that the init procedure had failed*/
        GKI_send_event(BTIF_TASK, BT_EVT_HARDWARE_INIT_FAIL);
    }
}

/*******************************************************************************
**
** Function        preload_start_wait_timer
**
** Description     Launch startup watchdog timer
**
** Returns         None
**
*******************************************************************************/
static void preload_start_wait_timer(void)
{
    int status;
    struct itimerspec ts;
    struct sigevent se;
    UINT32 timeout_ms = PRELOAD_START_TIMEOUT_MS;

    if (preload_retry_cb.timer_created == FALSE)
    {
        se.sigev_notify = SIGEV_THREAD;
        se.sigev_value.sival_ptr = &preload_retry_cb.timer_id;
        se.sigev_notify_function = preload_wait_timeout;
        se.sigev_notify_attributes = NULL;

        status = timer_create(CLOCK_MONOTONIC, &se, &preload_retry_cb.timer_id);

        if (status == 0)
            preload_retry_cb.timer_created = TRUE;
    }

    if (preload_retry_cb.timer_created == TRUE)
    {
        ts.it_value.tv_sec = timeout_ms/1000;
        ts.it_value.tv_nsec = 1000000*(timeout_ms%1000);
        ts.it_interval.tv_sec = 0;
        ts.it_interval.tv_nsec = 0;

        status = timer_settime(preload_retry_cb.timer_id, 0, &ts, 0);
        if (status == -1)
            APPL_TRACE_ERROR("Failed to fire preload watchdog timer");
    }
}

/*******************************************************************************
**
** Function        preload_stop_wait_timer
**
** Description     Stop preload watchdog timer
**
** Returns         None
**
*******************************************************************************/
static void preload_stop_wait_timer(void)
{
    if (preload_retry_cb.timer_created == TRUE)
    {
        timer_delete(preload_retry_cb.timer_id);
        preload_retry_cb.timer_created = FALSE;
    }
}

/******************************************************************************
**
** Function         bte_main_postload_cfg
**
** Description      BTE MAIN API - Stack postload configuration
**
** Returns          None
**
******************************************************************************/
void bte_main_postload_cfg(void)
{
    if (bt_hc_if)
        bt_hc_if->postload(NULL);
}

#if (defined(HCILP_INCLUDED) && HCILP_INCLUDED == TRUE)
/******************************************************************************
**
** Function         bte_main_enable_lpm
**
** Description      BTE MAIN API - Enable/Disable low power mode operation
**
** Returns          None
**
******************************************************************************/
void bte_main_enable_lpm(BOOLEAN enable)
{
    int result = -1;

    if (bt_hc_if)
        result = bt_hc_if->lpm( \
        (enable == TRUE) ? BT_HC_LPM_ENABLE : BT_HC_LPM_DISABLE \
        );

    APPL_TRACE_EVENT("HC lib lpm enable=%d return %d", enable, result);
}

/******************************************************************************
**
** Function         bte_main_lpm_allow_bt_device_sleep
**
** Description      BTE MAIN API - Allow BT controller goest to sleep
**
** Returns          None
**
******************************************************************************/
void bte_main_lpm_allow_bt_device_sleep()
{
    int result = -1;

    if ((bt_hc_if) && (lpm_enabled == TRUE))
        result = bt_hc_if->lpm(BT_HC_LPM_WAKE_DEASSERT);

    APPL_TRACE_DEBUG("HC lib lpm deassertion return %d", result);
}

/******************************************************************************
**
** Function         bte_main_lpm_wake_bt_device
**
** Description      BTE MAIN API - Wake BT controller up if it is in sleep mode
**
** Returns          None
**
******************************************************************************/
void bte_main_lpm_wake_bt_device()
{
    int result = -1;

    if ((bt_hc_if) && (lpm_enabled == TRUE))
        result = bt_hc_if->lpm(BT_HC_LPM_WAKE_ASSERT);

    APPL_TRACE_DEBUG("HC lib lpm assertion return %d", result);
}
#endif  // HCILP_INCLUDED


/* NOTICE:
 *  Definitions for audio state structure, this type needs to match to
 *  the bt_vendor_op_audio_state_t type defined in bt_vendor_lib.h
 */
typedef struct {
    UINT16  handle;
    UINT16  peer_codec;
    UINT16  state;
} bt_hc_audio_state_t;

struct bt_audio_state_tag {
    BT_HDR hdr;
    bt_hc_audio_state_t audio;
};

/******************************************************************************
**
** Function         set_audio_state
**
** Description      Sets audio state on controller state for SCO (PCM, WBS, FM)
**
** Parameters       handle: codec related handle for SCO: sco cb idx, unused for
**                  codec: BTA_AG_CODEC_MSBC, BTA_AG_CODEC_CSVD or FM codec
**                  state: codec state, eg. BTA_AG_CO_AUD_STATE_SETUP
**                  param: future extensions, e.g. call-in structure/event.
**
** Returns          None
**
******************************************************************************/
int set_audio_state(UINT16 handle, UINT16 codec, UINT8 state, void *param)
{
    struct bt_audio_state_tag *p_msg;
    int result = -1;

    APPL_TRACE_API("set_audio_state(handle: %d, codec: 0x%x, state: %d)", handle,
                    codec, state);
    if (NULL != param)
        APPL_TRACE_WARNING("set_audio_state() non-null param not supported");
    p_msg = (struct bt_audio_state_tag *)GKI_getbuf(sizeof(*p_msg));
    if (!p_msg)
        return result;
    p_msg->audio.handle = handle;
    p_msg->audio.peer_codec = codec;
    p_msg->audio.state = state;

    p_msg->hdr.event = MSG_CTRL_TO_HC_CMD | (MSG_SUB_EVT_MASK & BT_HC_AUDIO_STATE);
    p_msg->hdr.len = sizeof(p_msg->audio);
    p_msg->hdr.offset = 0;
    /* layer_specific shall contain return path event! for BTA events!
     * 0 means no return message is expected. */
    p_msg->hdr.layer_specific = 0;
       if (bt_hc_if)
       {
        bt_hc_if->tx_cmd((TRANSAC)p_msg, (char *)(&p_msg->audio), sizeof(*p_msg));
        }
    return result;
}


/******************************************************************************
**
** Function         bte_main_hci_send
**
** Description      BTE MAIN API - This function is called by the upper stack to
**                  send an HCI message. The function displays a protocol trace
**                  message (if enabled), and then calls the 'transmit' function
**                  associated with the currently selected HCI transport
**
** Returns          None
**
******************************************************************************/
void bte_main_hci_send (BT_HDR *p_msg, UINT16 event)
{
    UINT16 sub_event = event & BT_SUB_EVT_MASK;  /* local controller ID */

    p_msg->event = event;


    if((sub_event == LOCAL_BR_EDR_CONTROLLER_ID) || \
       (sub_event == LOCAL_BLE_CONTROLLER_ID))
    {
        if (bt_hc_if)
            bt_hc_if->transmit_buf((TRANSAC)p_msg, \
                                       (char *) (p_msg + 1), \
                                        p_msg->len);
        else
            GKI_freebuf(p_msg);
    }
    else
    {
        APPL_TRACE_ERROR("Invalid Controller ID. Discarding message.");
        GKI_freebuf(p_msg);
    }
}

/******************************************************************************
**
** Function         bte_main_post_reset_init
**
** Description      BTE MAIN API - This function is mapped to BTM_APP_DEV_INIT
**                  and shall be automatically called from BTE after HCI_Reset
**
** Returns          None
**
******************************************************************************/
void bte_main_post_reset_init()
{
    BTM_ContinueReset();
}

/*****************************************************************************
**
**   libbt-hci Callback Functions
**
*****************************************************************************/

/******************************************************************************
**
** Function         preload_cb
**
** Description      HOST/CONTROLLER LIB CALLBACK API - This function is called
**                  when the libbt-hci completed stack preload process
**
** Returns          None
**
******************************************************************************/
static void preload_cb(TRANSAC transac, bt_hc_preload_result_t result)
{
    UNUSED(transac);

    APPL_TRACE_EVENT("HC preload_cb %d [0:SUCCESS 1:FAIL]", result);

    if (result == BT_HC_PRELOAD_SUCCESS)
    {
        preload_stop_wait_timer();

        /* notify BTU task that libbt-hci is ready */
        GKI_send_event(BTU_TASK, BT_EVT_PRELOAD_CMPL);
    }
}

/******************************************************************************
**
** Function         postload_cb
**
** Description      HOST/CONTROLLER LIB CALLBACK API - This function is called
**                  when the libbt-hci lib completed stack postload process
**
** Returns          None
**
******************************************************************************/
static void postload_cb(TRANSAC transac, bt_hc_postload_result_t result)
{
    UNUSED(transac);

    APPL_TRACE_EVENT("HC postload_cb %d", result);
}

/******************************************************************************
**
** Function         lpm_cb
**
** Description      HOST/CONTROLLER LIB CALLBACK API - This function is called
**                  back from the libbt-hci to indicate the current LPM state
**
** Returns          None
**
******************************************************************************/
static void lpm_cb(bt_hc_lpm_request_result_t result)
{
    APPL_TRACE_EVENT("HC lpm_result_cb %d", result);
    lpm_enabled = (result == BT_HC_LPM_ENABLED) ? TRUE : FALSE;
}

/******************************************************************************
**
** Function         hostwake_ind
**
** Description      HOST/CONTROLLER LIB CALLOUT API - This function is called
**                  from the libbt-hci to indicate the HostWake event
**
** Returns          None
**
******************************************************************************/
static void hostwake_ind(bt_hc_low_power_event_t event)
{
    APPL_TRACE_EVENT("HC hostwake_ind %d", event);
}

/******************************************************************************
**
** Function         alloc
**
** Description      HOST/CONTROLLER LIB CALLOUT API - This function is called
**                  from the libbt-hci to request for data buffer allocation
**
** Returns          NULL / pointer to allocated buffer
**
******************************************************************************/
static char *alloc(int size)
{
    BT_HDR *p_hdr = NULL;

    /*
    APPL_TRACE_DEBUG("HC alloc size=%d", size);
    */

    /* Requested buffer size cannot exceed GKI_MAX_BUF_SIZE. */
    if (size > GKI_MAX_BUF_SIZE)
    {
         APPL_TRACE_ERROR("HCI DATA SIZE %d greater than MAX %d",
                           size, GKI_MAX_BUF_SIZE);
         return NULL;
    }

    p_hdr = (BT_HDR *) GKI_getbuf ((UINT16) size);

    if (p_hdr == NULL)
    {
        APPL_TRACE_WARNING("alloc returns NO BUFFER! (sz %d)", size);
    }

    return ((char *) p_hdr);
}

/******************************************************************************
**
** Function         dealloc
**
** Description      HOST/CONTROLLER LIB CALLOUT API - This function is called
**                  from the libbt-hci to release the data buffer allocated
**                  through the alloc call earlier
**
**                  Bluedroid libbt-hci library uses 'transac' parameter to
**                  pass data-path buffer/packet across bt_hci_lib interface
**                  boundary.
**
******************************************************************************/
static void dealloc(TRANSAC transac)
{
    GKI_freebuf(transac);
}

/******************************************************************************
**
** Function         data_ind
**
** Description      HOST/CONTROLLER LIB CALLOUT API - This function is called
**                  from the libbt-hci to pass in the received HCI packets
**
**                  The core stack is responsible for releasing the data buffer
**                  passed in from the libbt-hci once the core stack has done
**                  with it.
**
**                  Bluedroid libbt-hci library uses 'transac' parameter to
**                  pass data-path buffer/packet across bt_hci_lib interface
**                  boundary. The 'p_buf' and 'len' parameters are not intended
**                  to be used here but might point to data portion in data-
**                  path buffer and length of valid data respectively.
**
** Returns          bt_hc_status_t
**
******************************************************************************/
static int data_ind(TRANSAC transac, char *p_buf, int len)
{
    BT_HDR *p_msg = (BT_HDR *) transac;
    UNUSED(p_buf);
    UNUSED(len);

    /*
    APPL_TRACE_DEBUG("HC data_ind event=0x%04X (len=%d)", p_msg->event, len);
    */

    GKI_send_msg (BTU_TASK, BTU_HCI_RCV_MBOX, transac);
    return BT_HC_STATUS_SUCCESS;
}

/******************************************************************************
**
** Function         tx_result
**
** Description      HOST/CONTROLLER LIB CALLBACK API - This function is called
**                  from the libbt-hci once it has processed/sent the prior data
**                  buffer which core stack passed to it through transmit_buf
**                  call earlier.
**
**                  The core stack is responsible for releasing the data buffer
**                  if it has been completedly processed.
**
**                  Bluedroid libbt-hci library uses 'transac' parameter to
**                  pass data-path buffer/packet across bt_hci_lib interface
**                  boundary. The 'p_buf' is not intended to be used here
**                  but might point to data portion in data-path buffer.
**
** Returns          bt_hc_status_t
**
******************************************************************************/
static int tx_result(TRANSAC transac, char *p_buf, bt_hc_transmit_result_t result)
{
    UNUSED(p_buf);
    /*
    APPL_TRACE_DEBUG("HC tx_result %d (event=%04X)", result, \
                      ((BT_HDR *)transac)->event);
    */

    if (result == BT_HC_TX_FRAGMENT)
    {
        GKI_send_msg (BTU_TASK, BTU_HCI_RCV_MBOX, transac);
    }
    else
    {
        GKI_freebuf(transac);
    }

    return BT_HC_STATUS_SUCCESS;
}

/*****************************************************************************
**   The libbt-hci Callback Functions Table
*****************************************************************************/
static const bt_hc_callbacks_t hc_callbacks = {
    sizeof(bt_hc_callbacks_t),
    preload_cb,
    postload_cb,
    lpm_cb,
    hostwake_ind,
    alloc,
    dealloc,
    data_ind,
    tx_result
};