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      1 /******************************************************************************
      2  *
      3  *  Copyright (C) 2003-2012 Broadcom Corporation
      4  *
      5  *  Licensed under the Apache License, Version 2.0 (the "License");
      6  *  you may not use this file except in compliance with the License.
      7  *  You may obtain a copy of the License at:
      8  *
      9  *  http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  *  Unless required by applicable law or agreed to in writing, software
     12  *  distributed under the License is distributed on an "AS IS" BASIS,
     13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  *  See the License for the specific language governing permissions and
     15  *  limitations under the License.
     16  *
     17  ******************************************************************************/
     18 
     19 /******************************************************************************
     20  *
     21  *  This file contains the GATT client main functions and state machine.
     22  *
     23  ******************************************************************************/
     24 
     25 #include "bt_target.h"
     26 
     27 #include <string.h>
     28 
     29 #include "bt_common.h"
     30 #include "bta_gattc_int.h"
     31 
     32 /*****************************************************************************
     33  * Constants and types
     34  ****************************************************************************/
     35 
     36 /* state machine action enumeration list */
     37 enum {
     38   BTA_GATTC_OPEN,
     39   BTA_GATTC_OPEN_FAIL,
     40   BTA_GATTC_OPEN_ERROR,
     41   BTA_GATTC_CANCEL_OPEN,
     42   BTA_GATTC_CANCEL_OPEN_OK,
     43   BTA_GATTC_CANCEL_OPEN_ERROR,
     44   BTA_GATTC_CONN,
     45   BTA_GATTC_START_DISCOVER,
     46   BTA_GATTC_DISC_CMPL,
     47 
     48   BTA_GATTC_Q_CMD,
     49   BTA_GATTC_CLOSE,
     50   BTA_GATTC_CLOSE_FAIL,
     51   BTA_GATTC_READ,
     52   BTA_GATTC_WRITE,
     53 
     54   BTA_GATTC_OP_CMPL,
     55   BTA_GATTC_SEARCH,
     56   BTA_GATTC_FAIL,
     57   BTA_GATTC_CONFIRM,
     58   BTA_GATTC_EXEC,
     59   BTA_GATTC_READ_MULTI,
     60   BTA_GATTC_IGNORE_OP_CMPL,
     61   BTA_GATTC_DISC_CLOSE,
     62   BTA_GATTC_RESTART_DISCOVER,
     63   BTA_GATTC_CFG_MTU,
     64 
     65   BTA_GATTC_IGNORE
     66 };
     67 /* type for action functions */
     68 typedef void (*tBTA_GATTC_ACTION)(tBTA_GATTC_CLCB* p_clcb,
     69                                   tBTA_GATTC_DATA* p_data);
     70 
     71 /* action function list */
     72 const tBTA_GATTC_ACTION bta_gattc_action[] = {bta_gattc_open,
     73                                               bta_gattc_open_fail,
     74                                               bta_gattc_open_error,
     75                                               bta_gattc_cancel_open,
     76                                               bta_gattc_cancel_open_ok,
     77                                               bta_gattc_cancel_open_error,
     78                                               bta_gattc_conn,
     79                                               bta_gattc_start_discover,
     80                                               bta_gattc_disc_cmpl,
     81 
     82                                               bta_gattc_q_cmd,
     83                                               bta_gattc_close,
     84                                               bta_gattc_close_fail,
     85                                               bta_gattc_read,
     86                                               bta_gattc_write,
     87 
     88                                               bta_gattc_op_cmpl,
     89                                               bta_gattc_search,
     90                                               bta_gattc_fail,
     91                                               bta_gattc_confirm,
     92                                               bta_gattc_execute,
     93                                               bta_gattc_read_multi,
     94                                               bta_gattc_ignore_op_cmpl,
     95                                               bta_gattc_disc_close,
     96                                               bta_gattc_restart_discover,
     97                                               bta_gattc_cfg_mtu};
     98 
     99 /* state table information */
    100 #define BTA_GATTC_ACTIONS 1    /* number of actions */
    101 #define BTA_GATTC_NEXT_STATE 1 /* position of next state */
    102 #define BTA_GATTC_NUM_COLS 2   /* number of columns in state tables */
    103 
    104 /* state table for idle state */
    105 static const uint8_t bta_gattc_st_idle[][BTA_GATTC_NUM_COLS] = {
    106     /* Event                            Action 1                  Next state */
    107     /* BTA_GATTC_API_OPEN_EVT           */ {BTA_GATTC_OPEN,
    108                                             BTA_GATTC_W4_CONN_ST},
    109     /* BTA_GATTC_INT_OPEN_FAIL_EVT      */ {BTA_GATTC_IGNORE,
    110                                             BTA_GATTC_IDLE_ST},
    111     /* BTA_GATTC_API_CANCEL_OPEN_EVT    */ {BTA_GATTC_IGNORE,
    112                                             BTA_GATTC_IDLE_ST},
    113     /* BTA_GATTC_INT_CANCEL_OPEN_OK_EVT */ {BTA_GATTC_IGNORE,
    114                                             BTA_GATTC_IDLE_ST},
    115 
    116     /* BTA_GATTC_API_READ_EVT           */ {BTA_GATTC_FAIL, BTA_GATTC_IDLE_ST},
    117     /* BTA_GATTC_API_WRITE_EVT          */ {BTA_GATTC_FAIL, BTA_GATTC_IDLE_ST},
    118     /* BTA_GATTC_API_EXEC_EVT           */ {BTA_GATTC_FAIL, BTA_GATTC_IDLE_ST},
    119     /* BTA_GATTC_API_CFG_MTU_EVT        */ {BTA_GATTC_IGNORE,
    120                                             BTA_GATTC_IDLE_ST},
    121 
    122     /* BTA_GATTC_API_CLOSE_EVT          */ {BTA_GATTC_CLOSE_FAIL,
    123                                             BTA_GATTC_IDLE_ST},
    124 
    125     /* BTA_GATTC_API_SEARCH_EVT         */ {BTA_GATTC_FAIL, BTA_GATTC_IDLE_ST},
    126     /* BTA_GATTC_API_CONFIRM_EVT        */ {BTA_GATTC_FAIL, BTA_GATTC_IDLE_ST},
    127     /* BTA_GATTC_API_READ_MULTI_EVT     */ {BTA_GATTC_FAIL, BTA_GATTC_IDLE_ST},
    128 
    129     /* BTA_GATTC_INT_CONN_EVT           */ {BTA_GATTC_CONN, BTA_GATTC_CONN_ST},
    130     /* BTA_GATTC_INT_DISCOVER_EVT       */ {BTA_GATTC_IGNORE,
    131                                             BTA_GATTC_IDLE_ST},
    132     /* BTA_GATTC_DISCOVER_CMPL_EVT      */ {BTA_GATTC_IGNORE,
    133                                             BTA_GATTC_IDLE_ST},
    134     /* BTA_GATTC_OP_CMPL_EVT            */ {BTA_GATTC_IGNORE,
    135                                             BTA_GATTC_IDLE_ST},
    136     /* BTA_GATTC_INT_DISCONN_EVT       */ {BTA_GATTC_IGNORE, BTA_GATTC_IDLE_ST},
    137 
    138 };
    139 
    140 /* state table for wait for open state */
    141 static const uint8_t bta_gattc_st_w4_conn[][BTA_GATTC_NUM_COLS] = {
    142     /* Event                            Action 1 Next state */
    143     /* BTA_GATTC_API_OPEN_EVT           */ {BTA_GATTC_OPEN,
    144                                             BTA_GATTC_W4_CONN_ST},
    145     /* BTA_GATTC_INT_OPEN_FAIL_EVT      */ {BTA_GATTC_OPEN_FAIL,
    146                                             BTA_GATTC_IDLE_ST},
    147     /* BTA_GATTC_API_CANCEL_OPEN_EVT    */ {BTA_GATTC_CANCEL_OPEN,
    148                                             BTA_GATTC_W4_CONN_ST},
    149     /* BTA_GATTC_INT_CANCEL_OPEN_OK_EVT */ {BTA_GATTC_CANCEL_OPEN_OK,
    150                                             BTA_GATTC_IDLE_ST},
    151 
    152     /* BTA_GATTC_API_READ_EVT           */ {BTA_GATTC_FAIL,
    153                                             BTA_GATTC_W4_CONN_ST},
    154     /* BTA_GATTC_API_WRITE_EVT          */ {BTA_GATTC_FAIL,
    155                                             BTA_GATTC_W4_CONN_ST},
    156     /* BTA_GATTC_API_EXEC_EVT           */ {BTA_GATTC_FAIL,
    157                                             BTA_GATTC_W4_CONN_ST},
    158     /* BTA_GATTC_API_CFG_MTU_EVT        */ {BTA_GATTC_IGNORE,
    159                                             BTA_GATTC_W4_CONN_ST},
    160 
    161     /* BTA_GATTC_API_CLOSE_EVT          */ {BTA_GATTC_CANCEL_OPEN,
    162                                             BTA_GATTC_W4_CONN_ST},
    163 
    164     /* BTA_GATTC_API_SEARCH_EVT         */ {BTA_GATTC_FAIL,
    165                                             BTA_GATTC_W4_CONN_ST},
    166     /* BTA_GATTC_API_CONFIRM_EVT        */ {BTA_GATTC_FAIL,
    167                                             BTA_GATTC_W4_CONN_ST},
    168     /* BTA_GATTC_API_READ_MULTI_EVT     */ {BTA_GATTC_FAIL,
    169                                             BTA_GATTC_W4_CONN_ST},
    170 
    171     /* BTA_GATTC_INT_CONN_EVT           */ {BTA_GATTC_CONN, BTA_GATTC_CONN_ST},
    172     /* BTA_GATTC_INT_DISCOVER_EVT       */ {BTA_GATTC_IGNORE,
    173                                             BTA_GATTC_W4_CONN_ST},
    174     /* BTA_GATTC_DISCOVER_CMPL_EVT       */ {BTA_GATTC_IGNORE,
    175                                              BTA_GATTC_W4_CONN_ST},
    176     /* BTA_GATTC_OP_CMPL_EVT            */ {BTA_GATTC_IGNORE,
    177                                             BTA_GATTC_W4_CONN_ST},
    178     /* BTA_GATTC_INT_DISCONN_EVT      */ {BTA_GATTC_OPEN_FAIL,
    179                                           BTA_GATTC_IDLE_ST},
    180 
    181 };
    182 
    183 /* state table for open state */
    184 static const uint8_t bta_gattc_st_connected[][BTA_GATTC_NUM_COLS] = {
    185     /* Event                            Action 1 Next state */
    186     /* BTA_GATTC_API_OPEN_EVT           */ {BTA_GATTC_OPEN, BTA_GATTC_CONN_ST},
    187     /* BTA_GATTC_INT_OPEN_FAIL_EVT      */ {BTA_GATTC_IGNORE,
    188                                             BTA_GATTC_CONN_ST},
    189     /* BTA_GATTC_API_CANCEL_OPEN_EVT    */ {BTA_GATTC_CANCEL_OPEN_ERROR,
    190                                             BTA_GATTC_CONN_ST},
    191     /* BTA_GATTC_INT_CANCEL_OPEN_OK_EVT */ {BTA_GATTC_IGNORE,
    192                                             BTA_GATTC_CONN_ST},
    193 
    194     /* BTA_GATTC_API_READ_EVT           */ {BTA_GATTC_READ, BTA_GATTC_CONN_ST},
    195     /* BTA_GATTC_API_WRITE_EVT          */ {BTA_GATTC_WRITE, BTA_GATTC_CONN_ST},
    196     /* BTA_GATTC_API_EXEC_EVT           */ {BTA_GATTC_EXEC, BTA_GATTC_CONN_ST},
    197     /* BTA_GATTC_API_CFG_MTU_EVT        */ {BTA_GATTC_CFG_MTU,
    198                                             BTA_GATTC_CONN_ST},
    199 
    200     /* BTA_GATTC_API_CLOSE_EVT          */ {BTA_GATTC_CLOSE, BTA_GATTC_IDLE_ST},
    201 
    202     /* BTA_GATTC_API_SEARCH_EVT         */ {BTA_GATTC_SEARCH,
    203                                             BTA_GATTC_CONN_ST},
    204     /* BTA_GATTC_API_CONFIRM_EVT        */ {BTA_GATTC_CONFIRM,
    205                                             BTA_GATTC_CONN_ST},
    206     /* BTA_GATTC_API_READ_MULTI_EVT     */ {BTA_GATTC_READ_MULTI,
    207                                             BTA_GATTC_CONN_ST},
    208 
    209     /* BTA_GATTC_INT_CONN_EVT           */ {BTA_GATTC_IGNORE,
    210                                             BTA_GATTC_CONN_ST},
    211     /* BTA_GATTC_INT_DISCOVER_EVT       */ {BTA_GATTC_START_DISCOVER,
    212                                             BTA_GATTC_DISCOVER_ST},
    213     /* BTA_GATTC_DISCOVER_CMPL_EVT       */ {BTA_GATTC_IGNORE,
    214                                              BTA_GATTC_CONN_ST},
    215     /* BTA_GATTC_OP_CMPL_EVT            */ {BTA_GATTC_OP_CMPL,
    216                                             BTA_GATTC_CONN_ST},
    217 
    218     /* BTA_GATTC_INT_DISCONN_EVT        */ {BTA_GATTC_CLOSE, BTA_GATTC_IDLE_ST},
    219 
    220 };
    221 
    222 /* state table for discover state */
    223 static const uint8_t bta_gattc_st_discover[][BTA_GATTC_NUM_COLS] = {
    224     /* Event                            Action 1 Next state */
    225     /* BTA_GATTC_API_OPEN_EVT           */ {BTA_GATTC_OPEN,
    226                                             BTA_GATTC_DISCOVER_ST},
    227     /* BTA_GATTC_INT_OPEN_FAIL_EVT      */ {BTA_GATTC_IGNORE,
    228                                             BTA_GATTC_DISCOVER_ST},
    229     /* BTA_GATTC_API_CANCEL_OPEN_EVT    */ {BTA_GATTC_CANCEL_OPEN_ERROR,
    230                                             BTA_GATTC_DISCOVER_ST},
    231     /* BTA_GATTC_INT_CANCEL_OPEN_OK_EVT */ {BTA_GATTC_FAIL,
    232                                             BTA_GATTC_DISCOVER_ST},
    233 
    234     /* BTA_GATTC_API_READ_EVT           */ {BTA_GATTC_Q_CMD,
    235                                             BTA_GATTC_DISCOVER_ST},
    236     /* BTA_GATTC_API_WRITE_EVT          */ {BTA_GATTC_Q_CMD,
    237                                             BTA_GATTC_DISCOVER_ST},
    238     /* BTA_GATTC_API_EXEC_EVT           */ {BTA_GATTC_Q_CMD,
    239                                             BTA_GATTC_DISCOVER_ST},
    240     /* BTA_GATTC_API_CFG_MTU_EVT        */ {BTA_GATTC_Q_CMD,
    241                                             BTA_GATTC_DISCOVER_ST},
    242 
    243     /* BTA_GATTC_API_CLOSE_EVT          */ {BTA_GATTC_DISC_CLOSE,
    244                                             BTA_GATTC_DISCOVER_ST},
    245 
    246     /* BTA_GATTC_API_SEARCH_EVT         */ {BTA_GATTC_Q_CMD,
    247                                             BTA_GATTC_DISCOVER_ST},
    248     /* BTA_GATTC_API_CONFIRM_EVT        */ {BTA_GATTC_CONFIRM,
    249                                             BTA_GATTC_DISCOVER_ST},
    250     /* BTA_GATTC_API_READ_MULTI_EVT     */ {BTA_GATTC_Q_CMD,
    251                                             BTA_GATTC_DISCOVER_ST},
    252 
    253     /* BTA_GATTC_INT_CONN_EVT           */ {BTA_GATTC_CONN,
    254                                             BTA_GATTC_DISCOVER_ST},
    255     /* BTA_GATTC_INT_DISCOVER_EVT       */ {BTA_GATTC_RESTART_DISCOVER,
    256                                             BTA_GATTC_DISCOVER_ST},
    257     /* BTA_GATTC_DISCOVER_CMPL_EVT      */ {BTA_GATTC_DISC_CMPL,
    258                                             BTA_GATTC_CONN_ST},
    259     /* BTA_GATTC_OP_CMPL_EVT            */ {BTA_GATTC_IGNORE_OP_CMPL,
    260                                             BTA_GATTC_DISCOVER_ST},
    261     /* BTA_GATTC_INT_DISCONN_EVT        */ {BTA_GATTC_CLOSE, BTA_GATTC_IDLE_ST},
    262 
    263 };
    264 
    265 /* type for state table */
    266 typedef const uint8_t (*tBTA_GATTC_ST_TBL)[BTA_GATTC_NUM_COLS];
    267 
    268 /* state table */
    269 const tBTA_GATTC_ST_TBL bta_gattc_st_tbl[] = {
    270     bta_gattc_st_idle, bta_gattc_st_w4_conn, bta_gattc_st_connected,
    271     bta_gattc_st_discover};
    272 
    273 /*****************************************************************************
    274  * Global data
    275  ****************************************************************************/
    276 
    277 /* GATTC control block */
    278 tBTA_GATTC_CB bta_gattc_cb;
    279 
    280 #if (BTA_GATT_DEBUG == TRUE)
    281 static char* gattc_evt_code(tBTA_GATTC_INT_EVT evt_code);
    282 static char* gattc_state_code(tBTA_GATTC_STATE state_code);
    283 #endif
    284 
    285 /*******************************************************************************
    286  *
    287  * Function         bta_gattc_sm_execute
    288  *
    289  * Description      State machine event handling function for GATTC
    290  *
    291  *
    292  * Returns          bool  : true if queued client request buffer can be
    293  *                          immediately released, else false
    294  *
    295  ******************************************************************************/
    296 bool bta_gattc_sm_execute(tBTA_GATTC_CLCB* p_clcb, uint16_t event,
    297                           tBTA_GATTC_DATA* p_data) {
    298   tBTA_GATTC_ST_TBL state_table;
    299   uint8_t action;
    300   int i;
    301   bool rt = true;
    302 #if (BTA_GATT_DEBUG == TRUE)
    303   tBTA_GATTC_STATE in_state = p_clcb->state;
    304   uint16_t in_event = event;
    305   APPL_TRACE_DEBUG("bta_gattc_sm_execute: State 0x%02x [%s], Event 0x%x[%s]",
    306                    in_state, gattc_state_code(in_state), in_event,
    307                    gattc_evt_code(in_event));
    308 #endif
    309 
    310   /* look up the state table for the current state */
    311   state_table = bta_gattc_st_tbl[p_clcb->state];
    312 
    313   event &= 0x00FF;
    314 
    315   /* set next state */
    316   p_clcb->state = state_table[event][BTA_GATTC_NEXT_STATE];
    317 
    318   /* execute action functions */
    319   for (i = 0; i < BTA_GATTC_ACTIONS; i++) {
    320     action = state_table[event][i];
    321     if (action != BTA_GATTC_IGNORE) {
    322       (*bta_gattc_action[action])(p_clcb, p_data);
    323       if (p_clcb->p_q_cmd == p_data) {
    324         /* buffer is queued, don't free in the bta dispatcher.
    325          * we free it ourselves when a completion event is received.
    326          */
    327         rt = false;
    328       }
    329     } else {
    330       break;
    331     }
    332   }
    333 
    334 #if (BTA_GATT_DEBUG == TRUE)
    335   if (in_state != p_clcb->state) {
    336     APPL_TRACE_DEBUG("GATTC State Change: [%s] -> [%s] after Event [%s]",
    337                      gattc_state_code(in_state),
    338                      gattc_state_code(p_clcb->state), gattc_evt_code(in_event));
    339   }
    340 #endif
    341   return rt;
    342 }
    343 
    344 /*******************************************************************************
    345  *
    346  * Function         bta_gattc_hdl_event
    347  *
    348  * Description      GATT client main event handling function.
    349  *
    350  *
    351  * Returns          bool
    352  *
    353  ******************************************************************************/
    354 bool bta_gattc_hdl_event(BT_HDR* p_msg) {
    355   tBTA_GATTC_CLCB* p_clcb = NULL;
    356   bool rt = true;
    357 #if (BTA_GATT_DEBUG == TRUE)
    358   APPL_TRACE_DEBUG("bta_gattc_hdl_event: Event [%s]",
    359                    gattc_evt_code(p_msg->event));
    360 #endif
    361   switch (p_msg->event) {
    362 
    363     case BTA_GATTC_API_OPEN_EVT:
    364       bta_gattc_process_api_open((tBTA_GATTC_DATA*)p_msg);
    365       break;
    366 
    367     case BTA_GATTC_API_CANCEL_OPEN_EVT:
    368       bta_gattc_process_api_open_cancel((tBTA_GATTC_DATA*)p_msg);
    369       break;
    370 
    371     default:
    372       if (p_msg->event == BTA_GATTC_INT_CONN_EVT)
    373         p_clcb = bta_gattc_find_int_conn_clcb((tBTA_GATTC_DATA*)p_msg);
    374       else if (p_msg->event == BTA_GATTC_INT_DISCONN_EVT)
    375         p_clcb = bta_gattc_find_int_disconn_clcb((tBTA_GATTC_DATA*)p_msg);
    376       else
    377         p_clcb = bta_gattc_find_clcb_by_conn_id(p_msg->layer_specific);
    378 
    379       if (p_clcb != NULL) {
    380         rt =
    381             bta_gattc_sm_execute(p_clcb, p_msg->event, (tBTA_GATTC_DATA*)p_msg);
    382       } else {
    383         APPL_TRACE_DEBUG("Ignore unknown conn ID: %d", p_msg->layer_specific);
    384       }
    385 
    386       break;
    387   }
    388 
    389   return rt;
    390 }
    391 
    392 /*****************************************************************************
    393  *  Debug Functions
    394  ****************************************************************************/
    395 #if (BTA_GATT_DEBUG == TRUE)
    396 
    397 /*******************************************************************************
    398  *
    399  * Function         gattc_evt_code
    400  *
    401  * Description
    402  *
    403  * Returns          void
    404  *
    405  ******************************************************************************/
    406 static char* gattc_evt_code(tBTA_GATTC_INT_EVT evt_code) {
    407   switch (evt_code) {
    408     case BTA_GATTC_API_OPEN_EVT:
    409       return "BTA_GATTC_API_OPEN_EVT";
    410     case BTA_GATTC_INT_OPEN_FAIL_EVT:
    411       return "BTA_GATTC_INT_OPEN_FAIL_EVT";
    412     case BTA_GATTC_API_CANCEL_OPEN_EVT:
    413       return "BTA_GATTC_API_CANCEL_OPEN_EVT";
    414     case BTA_GATTC_INT_CANCEL_OPEN_OK_EVT:
    415       return "BTA_GATTC_INT_CANCEL_OPEN_OK_EVT";
    416     case BTA_GATTC_API_READ_EVT:
    417       return "BTA_GATTC_API_READ_EVT";
    418     case BTA_GATTC_API_WRITE_EVT:
    419       return "BTA_GATTC_API_WRITE_EVT";
    420     case BTA_GATTC_API_EXEC_EVT:
    421       return "BTA_GATTC_API_EXEC_EVT";
    422     case BTA_GATTC_API_CLOSE_EVT:
    423       return "BTA_GATTC_API_CLOSE_EVT";
    424     case BTA_GATTC_API_SEARCH_EVT:
    425       return "BTA_GATTC_API_SEARCH_EVT";
    426     case BTA_GATTC_API_CONFIRM_EVT:
    427       return "BTA_GATTC_API_CONFIRM_EVT";
    428     case BTA_GATTC_API_READ_MULTI_EVT:
    429       return "BTA_GATTC_API_READ_MULTI_EVT";
    430     case BTA_GATTC_INT_CONN_EVT:
    431       return "BTA_GATTC_INT_CONN_EVT";
    432     case BTA_GATTC_INT_DISCOVER_EVT:
    433       return "BTA_GATTC_INT_DISCOVER_EVT";
    434     case BTA_GATTC_DISCOVER_CMPL_EVT:
    435       return "BTA_GATTC_DISCOVER_CMPL_EVT";
    436     case BTA_GATTC_OP_CMPL_EVT:
    437       return "BTA_GATTC_OP_CMPL_EVT";
    438     case BTA_GATTC_INT_DISCONN_EVT:
    439       return "BTA_GATTC_INT_DISCONN_EVT";
    440     case BTA_GATTC_API_CFG_MTU_EVT:
    441       return "BTA_GATTC_API_CFG_MTU_EVT";
    442     default:
    443       return "unknown GATTC event code";
    444   }
    445 }
    446 
    447 /*******************************************************************************
    448  *
    449  * Function         gattc_state_code
    450  *
    451  * Description
    452  *
    453  * Returns          void
    454  *
    455  ******************************************************************************/
    456 static char* gattc_state_code(tBTA_GATTC_STATE state_code) {
    457   switch (state_code) {
    458     case BTA_GATTC_IDLE_ST:
    459       return "GATTC_IDLE_ST";
    460     case BTA_GATTC_W4_CONN_ST:
    461       return "GATTC_W4_CONN_ST";
    462     case BTA_GATTC_CONN_ST:
    463       return "GATTC_CONN_ST";
    464     case BTA_GATTC_DISCOVER_ST:
    465       return "GATTC_DISCOVER_ST";
    466     default:
    467       return "unknown GATTC state code";
    468   }
    469 }
    470 
    471 #endif /* Debug Functions */
    472