bt/stack/gap/gap_ble.cc

/******************************************************************************
 *
 *  Copyright (C) 2009-2013 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.
 *
 ******************************************************************************/
#include "bt_target.h"

#if (BLE_INCLUDED == TRUE)

#include "bt_utils.h"
#include <string.h>
#include "gap_int.h"
#include "gap_api.h"
#include "gattdefs.h"
#include "gatt_api.h"
#include "gatt_int.h"
#include "btm_int.h"
#include "hcimsgs.h"
#include "btcore/include/uuid.h"
#include "osi/include/osi.h"

#define GAP_CHAR_ICON_SIZE          2
#define GAP_CHAR_DEV_NAME_SIZE      248
#define GAP_MAX_NUM_INC_SVR       0
#define GAP_MAX_ATTR_NUM          (2 * GAP_MAX_CHAR_NUM + GAP_MAX_NUM_INC_SVR + 1)
#define GAP_MAX_CHAR_VALUE_SIZE   (30 + GAP_CHAR_DEV_NAME_SIZE)


#ifndef GAP_ATTR_DB_SIZE
#define GAP_ATTR_DB_SIZE      GATT_DB_MEM_SIZE(GAP_MAX_NUM_INC_SVR, GAP_MAX_CHAR_NUM, GAP_MAX_CHAR_VALUE_SIZE)
#endif

static void gap_ble_s_attr_request_cback (uint16_t conn_id, uint32_t trans_id, tGATTS_REQ_TYPE op_code, tGATTS_DATA *p_data);

/* client connection callback */
static void  gap_ble_c_connect_cback (tGATT_IF gatt_if, BD_ADDR bda, uint16_t conn_id, bool connected,
                                      tGATT_DISCONN_REASON reason, tGATT_TRANSPORT transport);
static void  gap_ble_c_cmpl_cback (uint16_t conn_id, tGATTC_OPTYPE op, tGATT_STATUS status, tGATT_CL_COMPLETE *p_data);

static tGATT_CBACK gap_cback =
{
    gap_ble_c_connect_cback,
    gap_ble_c_cmpl_cback,
    NULL,
    NULL,
    gap_ble_s_attr_request_cback,
    NULL,
    NULL
};



/*******************************************************************************
**
** Function         gap_find_clcb_by_bd_addr
**
** Description      The function searches all LCB with macthing bd address
**
** Returns          total number of clcb found.
**
*******************************************************************************/
tGAP_CLCB *gap_find_clcb_by_bd_addr(BD_ADDR bda)
{
    uint8_t i_clcb;
    tGAP_CLCB    *p_clcb = NULL;

    for (i_clcb = 0, p_clcb= gap_cb.clcb; i_clcb < GAP_MAX_CL; i_clcb++, p_clcb++)
    {
        if (p_clcb->in_use && !memcmp(p_clcb->bda, bda, BD_ADDR_LEN))
        {
            return p_clcb;
        }
    }

    return NULL;
}

/*******************************************************************************
**
** Function         gap_ble_find_clcb_by_conn_id
**
** Description      The function searches all LCB with macthing connection ID
**
** Returns          total number of clcb found.
**
*******************************************************************************/
tGAP_CLCB *gap_ble_find_clcb_by_conn_id(uint16_t conn_id)
{
    uint8_t i_clcb;
    tGAP_CLCB    *p_clcb = NULL;

    for (i_clcb = 0, p_clcb= gap_cb.clcb; i_clcb < GAP_MAX_CL; i_clcb++, p_clcb++)
    {
        if (p_clcb->in_use && p_clcb->connected && p_clcb->conn_id == conn_id)
        {
            return p_clcb;
        }
    }

    return p_clcb;
}

/*******************************************************************************
**
** Function         gap_clcb_alloc
**
** Description      The function allocates a GAP  connection link control block
**
** Returns           NULL if not found. Otherwise pointer to the connection link block.
**
*******************************************************************************/
tGAP_CLCB *gap_clcb_alloc (BD_ADDR bda)
{
    uint8_t       i_clcb = 0;
    tGAP_CLCB    *p_clcb = NULL;

    for (i_clcb = 0, p_clcb= gap_cb.clcb; i_clcb < GAP_MAX_CL; i_clcb++, p_clcb++)
    {
        if (!p_clcb->in_use)
        {
            fixed_queue_free(p_clcb->pending_req_q, NULL);
            memset(p_clcb, 0, sizeof(tGAP_CLCB));
            p_clcb->in_use = true;
            memcpy (p_clcb->bda, bda, BD_ADDR_LEN);
            p_clcb->pending_req_q = fixed_queue_new(SIZE_MAX);
            break;
        }
    }
    return p_clcb;
}

/*******************************************************************************
**
** Function         gap_ble_dealloc_clcb
**
** Description      The function clean up the pending request queue in GAP
**
** Returns          none
**
*******************************************************************************/
void gap_ble_dealloc_clcb(tGAP_CLCB *p_clcb)
{
    tGAP_BLE_REQ    *p_q;

    while ((p_q = (tGAP_BLE_REQ *)fixed_queue_try_dequeue(p_clcb->pending_req_q)) != NULL)
    {
         /* send callback to all pending requests if being removed*/
         if (p_q->p_cback != NULL)
            (*p_q->p_cback)(false, p_clcb->bda, 0, NULL);

         osi_free(p_q);
    }
    fixed_queue_free(p_clcb->pending_req_q, NULL);

    memset(p_clcb, 0, sizeof(tGAP_CLCB));
}

/*******************************************************************************
**
** Function         gap_ble_enqueue_request
**
** Description      The function enqueue a GAP client request
**
** Returns           true is successul; false otherwise
**
*******************************************************************************/
bool    gap_ble_enqueue_request (tGAP_CLCB *p_clcb, uint16_t uuid, tGAP_BLE_CMPL_CBACK *p_cback)
{
    tGAP_BLE_REQ *p_q = (tGAP_BLE_REQ *)osi_malloc(sizeof(tGAP_BLE_REQ));

    p_q->p_cback = p_cback;
    p_q->uuid = uuid;
    fixed_queue_enqueue(p_clcb->pending_req_q, p_q);

    return true;
}

/*******************************************************************************
**
** Function         gap_ble_dequeue_request
**
** Description      The function dequeue a GAP client request if any
**
** Returns           true is successul; false otherwise
**
*******************************************************************************/
bool    gap_ble_dequeue_request (tGAP_CLCB *p_clcb, uint16_t * p_uuid, tGAP_BLE_CMPL_CBACK **p_cback)
{
    tGAP_BLE_REQ *p_q = (tGAP_BLE_REQ *)fixed_queue_try_dequeue(p_clcb->pending_req_q);;

    if (p_q != NULL)
    {
        *p_cback    = p_q->p_cback;
        *p_uuid     = p_q->uuid;
        osi_free(p_q);
        return true;
    }

    return false;
}

/*******************************************************************************
**   GAP Attributes Database Request callback
*******************************************************************************/
tGATT_STATUS gap_read_attr_value (uint16_t handle, tGATT_VALUE *p_value, bool    is_long)
{
    tGAP_ATTR   *p_db_attr = gap_cb.gatt_attr;
    uint8_t     *p = p_value->value, i;
    uint16_t    offset = p_value->offset;
    uint8_t     *p_dev_name = NULL;

    for (i = 0; i < GAP_MAX_CHAR_NUM; i ++, p_db_attr ++)
    {
        if (handle == p_db_attr->handle)
        {
            if (p_db_attr->uuid != GATT_UUID_GAP_DEVICE_NAME &&
                is_long == true)
                return GATT_NOT_LONG;

            switch (p_db_attr->uuid)
            {
                case GATT_UUID_GAP_DEVICE_NAME:
                    BTM_ReadLocalDeviceName((char **)&p_dev_name);
                    if (strlen ((char *)p_dev_name) > GATT_MAX_ATTR_LEN)
                        p_value->len = GATT_MAX_ATTR_LEN;
                    else
                        p_value->len = (uint16_t)strlen ((char *)p_dev_name);

                    if (offset > p_value->len)
                        return GATT_INVALID_OFFSET;
                    else
                    {
                        p_value->len -= offset;
                        p_dev_name += offset;
                        ARRAY_TO_STREAM(p, p_dev_name, p_value->len);
                        GAP_TRACE_EVENT("GATT_UUID_GAP_DEVICE_NAME len=0x%04x", p_value->len);
                    }
                    break;

                case GATT_UUID_GAP_ICON:
                    UINT16_TO_STREAM(p, p_db_attr->attr_value.icon);
                    p_value->len = 2;
                    break;

                case GATT_UUID_GAP_PREF_CONN_PARAM:
                    UINT16_TO_STREAM(p, p_db_attr->attr_value.conn_param.int_min); /* int_min */
                    UINT16_TO_STREAM(p, p_db_attr->attr_value.conn_param.int_max); /* int_max */
                    UINT16_TO_STREAM(p, p_db_attr->attr_value.conn_param.latency); /* latency */
                    UINT16_TO_STREAM(p, p_db_attr->attr_value.conn_param.sp_tout);  /* sp_tout */
                    p_value->len =8;
                    break;

                /* address resolution */
                case GATT_UUID_GAP_CENTRAL_ADDR_RESOL:
                    UINT8_TO_STREAM(p, p_db_attr->attr_value.addr_resolution);
                    p_value->len =1;
                    break;
            }
            return GATT_SUCCESS;
        }
    }
    return GATT_NOT_FOUND;
}

/*******************************************************************************
**   GAP Attributes Database Read/Read Blob Request process
*******************************************************************************/
tGATT_STATUS gap_proc_read (UNUSED_ATTR tGATTS_REQ_TYPE type, tGATT_READ_REQ *p_data,
                            tGATTS_RSP *p_rsp)
{
    tGATT_STATUS    status = GATT_NO_RESOURCES;

    if (p_data->is_long)
        p_rsp->attr_value.offset = p_data->offset;

    p_rsp->attr_value.handle = p_data->handle;

    status = gap_read_attr_value(p_data->handle, &p_rsp->attr_value, p_data->is_long);

    return status;
}

/******************************************************************************
**
** Function         gap_proc_write_req
**
** Description      GAP ATT server process a write request.
**
** Returns          void.
**
*******************************************************************************/
uint8_t gap_proc_write_req(UNUSED_ATTR tGATTS_REQ_TYPE type, tGATT_WRITE_REQ *p_data)
{
    tGAP_ATTR   *p_db_attr = gap_cb.gatt_attr;
    uint8_t i;

    for (i = 0; i < GAP_MAX_CHAR_NUM; i ++, p_db_attr ++)
    {
        if (p_data-> handle == p_db_attr->handle)
        {
                return GATT_WRITE_NOT_PERMIT;
        }
    }
    return GATT_NOT_FOUND;

}

/******************************************************************************
**
** Function         gap_ble_s_attr_request_cback
**
** Description      GAP ATT server attribute access request callback.
**
** Returns          void.
**
*******************************************************************************/
void gap_ble_s_attr_request_cback (uint16_t conn_id, uint32_t trans_id,
                                   tGATTS_REQ_TYPE type, tGATTS_DATA *p_data)
{
    uint8_t     status = GATT_INVALID_PDU;
    tGATTS_RSP  rsp_msg;
    bool        ignore = false;

    GAP_TRACE_EVENT("gap_ble_s_attr_request_cback : recv type (0x%02x)", type);

    memset(&rsp_msg, 0, sizeof(tGATTS_RSP));

    switch (type)
    {
        case GATTS_REQ_TYPE_READ_CHARACTERISTIC:
        case GATTS_REQ_TYPE_READ_DESCRIPTOR:
            status = gap_proc_read(type, &p_data->read_req, &rsp_msg);
            break;

        case GATTS_REQ_TYPE_WRITE_CHARACTERISTIC:
        case GATTS_REQ_TYPE_WRITE_DESCRIPTOR:
            if (!p_data->write_req.need_rsp)
                ignore = true;

            status = gap_proc_write_req(type, &p_data->write_req);
            break;

        case GATTS_REQ_TYPE_WRITE_EXEC:
            ignore = true;
            GAP_TRACE_EVENT("Ignore GATTS_REQ_TYPE_WRITE_EXEC"  );
            break;

        case GATTS_REQ_TYPE_MTU:
            GAP_TRACE_EVENT("Get MTU exchange new mtu size: %d", p_data->mtu);
            ignore = true;
            break;

        default:
            GAP_TRACE_EVENT("Unknown/unexpected LE GAP ATT request: 0x%02x", type);
            break;
    }

    if (!ignore)
        GATTS_SendRsp (conn_id, trans_id, status, &rsp_msg);
}

/*******************************************************************************
**
** Function         btm_ble_att_db_init
**
** Description      GAP ATT database initalization.
**
** Returns          void.
**
*******************************************************************************/
void gap_attr_db_init(void)
{
    tBT_UUID        app_uuid = {LEN_UUID_128,{0}};
    uint16_t        service_handle;

    /* Fill our internal UUID with a fixed pattern 0x82 */
    memset (&app_uuid.uu.uuid128, 0x82, LEN_UUID_128);
    memset(gap_cb.gatt_attr, 0, sizeof(tGAP_ATTR) *GAP_MAX_CHAR_NUM);

    gap_cb.gatt_if = GATT_Register(&app_uuid, &gap_cback);

    GATT_StartIf(gap_cb.gatt_if);

    bt_uuid_t svc_uuid, name_uuid, icon_uuid, pref_uuid, addr_res_uuid;
    uuid_128_from_16(&svc_uuid, UUID_SERVCLASS_GAP_SERVER);
    uuid_128_from_16(&name_uuid, GATT_UUID_GAP_DEVICE_NAME);
    uuid_128_from_16(&icon_uuid, GATT_UUID_GAP_ICON);
    uuid_128_from_16(&pref_uuid, GATT_UUID_GAP_PREF_CONN_PARAM);
    uuid_128_from_16(&addr_res_uuid, GATT_UUID_GAP_CENTRAL_ADDR_RESOL);

    btgatt_db_element_t service[] = {
        {.type = BTGATT_DB_PRIMARY_SERVICE, .uuid = svc_uuid},
        {.type = BTGATT_DB_CHARACTERISTIC, .uuid = name_uuid, .properties = GATT_CHAR_PROP_BIT_READ, .permissions = GATT_PERM_READ},
        {.type = BTGATT_DB_CHARACTERISTIC, .uuid = icon_uuid, .properties = GATT_CHAR_PROP_BIT_READ, .permissions = GATT_PERM_READ},
        {.type = BTGATT_DB_CHARACTERISTIC, .uuid = addr_res_uuid, .properties = GATT_CHAR_PROP_BIT_READ, .permissions = GATT_PERM_READ}
#if (BTM_PERIPHERAL_ENABLED == TRUE)       /* Only needed for peripheral testing */
        ,{.type = BTGATT_DB_CHARACTERISTIC, .uuid = pref_uuid, .properties = GATT_CHAR_PROP_BIT_READ, .permissions = GATT_PERM_READ}
#endif
    };

    /* Add a GAP service */
    GATTS_AddService(gap_cb.gatt_if, service, sizeof(service)/sizeof(btgatt_db_element_t));
    service_handle = service[0].attribute_handle;

    GAP_TRACE_EVENT("%s: service_handle = %d",__func__, service_handle);

    gap_cb.gatt_attr[0].uuid = GATT_UUID_GAP_DEVICE_NAME;
    gap_cb.gatt_attr[0].handle = service[1].attribute_handle;

    gap_cb.gatt_attr[1].uuid = GATT_UUID_GAP_ICON;
    gap_cb.gatt_attr[1].handle = service[2].attribute_handle;

    gap_cb.gatt_attr[2].uuid = GATT_UUID_GAP_CENTRAL_ADDR_RESOL;
    gap_cb.gatt_attr[2].handle = service[3].attribute_handle;
    gap_cb.gatt_attr[2].attr_value.addr_resolution = 0;

#if (BTM_PERIPHERAL_ENABLED == TRUE)     /*  Only needed for peripheral testing */

    gap_cb.gatt_attr[3].uuid = GATT_UUID_GAP_PREF_CONN_PARAM;
    gap_cb.gatt_attr[3].attr_value.conn_param.int_max = GAP_PREFER_CONN_INT_MAX; /* 6 */
    gap_cb.gatt_attr[3].attr_value.conn_param.int_min = GAP_PREFER_CONN_INT_MIN; /* 0 */
    gap_cb.gatt_attr[3].attr_value.conn_param.latency = GAP_PREFER_CONN_LATENCY; /* 0 */
    gap_cb.gatt_attr[3].attr_value.conn_param.sp_tout = GAP_PREFER_CONN_SP_TOUT; /* 2000 */
    gap_cb.gatt_attr[3].handle = service[4].attribute_handle;
#endif
}

/*******************************************************************************
**
** Function         GAP_BleAttrDBUpdate
**
** Description      GAP ATT database update.
**
** Returns          void.
**
*******************************************************************************/
void GAP_BleAttrDBUpdate(uint16_t attr_uuid, tGAP_BLE_ATTR_VALUE *p_value)
{
    tGAP_ATTR  *p_db_attr = gap_cb.gatt_attr;
    uint8_t     i = 0;

    GAP_TRACE_EVENT("GAP_BleAttrDBUpdate attr_uuid=0x%04x", attr_uuid);

    for (i = 0; i < GAP_MAX_CHAR_NUM; i ++, p_db_attr ++)
    {
        if (p_db_attr->uuid == attr_uuid)
        {
            GAP_TRACE_EVENT("Found attr_uuid=0x%04x", attr_uuid);

            switch (attr_uuid)
            {
            case GATT_UUID_GAP_ICON:
                p_db_attr->attr_value.icon  =  p_value->icon;
                break;

            case GATT_UUID_GAP_PREF_CONN_PARAM:
                memcpy((void *)&p_db_attr->attr_value.conn_param,
                       (const void *)&p_value->conn_param, sizeof(tGAP_BLE_PREF_PARAM));
                break;

            case GATT_UUID_GAP_DEVICE_NAME:
                BTM_SetLocalDeviceName((char *)p_value->p_dev_name);
                break;

            case GATT_UUID_GAP_CENTRAL_ADDR_RESOL:
                p_db_attr->attr_value.addr_resolution = p_value->addr_resolution;
                break;

            }
            break;
        }
    }

    return;
}

/*******************************************************************************
**
** Function         gap_ble_send_cl_read_request
**
** Description      utility function to send a read request for a GAP charactersitic
**
** Returns          true if read started, else false if GAP is busy
**
*******************************************************************************/
bool    gap_ble_send_cl_read_request(tGAP_CLCB *p_clcb)
{
    tGATT_READ_PARAM        param;
    uint16_t                uuid = 0;
    bool                    started = false;

    if (gap_ble_dequeue_request(p_clcb, &uuid, &p_clcb->p_cback))
    {
        memset(&param, 0, sizeof(tGATT_READ_PARAM));

        param.service.uuid.len       = LEN_UUID_16;
        param.service.uuid.uu.uuid16 = uuid;
        param.service.s_handle       = 1;
        param.service.e_handle       = 0xFFFF;
        param.service.auth_req       = 0;

        if (GATTC_Read(p_clcb->conn_id, GATT_READ_BY_TYPE, &param) == GATT_SUCCESS)
        {
            p_clcb->cl_op_uuid = uuid;
            started = true;
        }
    }

    return started;
}

/*******************************************************************************
**
** Function         gap_ble_cl_op_cmpl
**
** Description      GAP client operation complete callback
**
** Returns          void
**
*******************************************************************************/
void gap_ble_cl_op_cmpl(tGAP_CLCB *p_clcb, bool    status, uint16_t len, uint8_t *p_name)
{
    tGAP_BLE_CMPL_CBACK *p_cback = p_clcb->p_cback;
    uint16_t                op = p_clcb->cl_op_uuid;

    GAP_TRACE_EVENT("gap_ble_cl_op_cmpl status: %d", status);

    p_clcb->cl_op_uuid = 0;
    p_clcb->p_cback=NULL;

    if (p_cback && op)
    {
        GAP_TRACE_EVENT("calling gap_ble_cl_op_cmpl");
        (* p_cback)(status, p_clcb->bda, len, (char *)p_name);
    }

    /* if no further activity is requested in callback, drop the link */
    if (p_clcb->connected)
    {
        if (!gap_ble_send_cl_read_request(p_clcb))
        {
            GATT_Disconnect(p_clcb->conn_id);
            gap_ble_dealloc_clcb(p_clcb);
        }
    }
}

/*******************************************************************************
**
** Function         gap_ble_c_connect_cback
**
** Description      Client connection callback.
**
** Returns          void
**
*******************************************************************************/
static void gap_ble_c_connect_cback (UNUSED_ATTR tGATT_IF gatt_if, BD_ADDR bda,
                                     uint16_t conn_id,
                                     bool    connected, tGATT_DISCONN_REASON reason,
                                     UNUSED_ATTR tGATT_TRANSPORT transport)
{
    tGAP_CLCB   *p_clcb = gap_find_clcb_by_bd_addr (bda);

    if (p_clcb != NULL)
    {
        if (connected)
        {
            p_clcb->conn_id = conn_id;
            p_clcb->connected = true;
            /* start operation is pending */
            gap_ble_send_cl_read_request(p_clcb);
        }
        else
        {
            p_clcb->connected = false;
            gap_ble_cl_op_cmpl(p_clcb, false, 0, NULL);
            /* clean up clcb */
            gap_ble_dealloc_clcb(p_clcb);
        }
    }
}

/*******************************************************************************
**
** Function         gap_ble_c_cmpl_cback
**
** Description      Client operation complete callback.
**
** Returns          void
**
*******************************************************************************/
static void gap_ble_c_cmpl_cback (uint16_t conn_id, tGATTC_OPTYPE op, tGATT_STATUS status, tGATT_CL_COMPLETE *p_data)

{
    tGAP_CLCB   *p_clcb = gap_ble_find_clcb_by_conn_id(conn_id);
    uint16_t    op_type;
    uint16_t    min, max, latency, tout;
    uint16_t    len;
    uint8_t     *pp;

    if (p_clcb == NULL)
        return;

    op_type = p_clcb->cl_op_uuid;

    GAP_TRACE_EVENT ("gap_ble_c_cmpl_cback() - op_code: 0x%02x  status: 0x%02x  read_type: 0x%04x", op, status, op_type);
    /* Currently we only issue read commands */
    if (op != GATTC_OPTYPE_READ)
        return;

    if (status != GATT_SUCCESS)
    {
        gap_ble_cl_op_cmpl(p_clcb, false, 0, NULL);
        return;
    }

    pp = p_data->att_value.value;

    switch (op_type)
    {
        case GATT_UUID_GAP_PREF_CONN_PARAM:
            GAP_TRACE_EVENT ("GATT_UUID_GAP_PREF_CONN_PARAM");
            /* Extract the peripheral preferred connection parameters and save them */

            STREAM_TO_UINT16 (min, pp);
            STREAM_TO_UINT16 (max, pp);
            STREAM_TO_UINT16 (latency, pp);
            STREAM_TO_UINT16 (tout, pp);

            BTM_BleSetPrefConnParams (p_clcb->bda, min, max, latency, tout);
            /* release the connection here */
            gap_ble_cl_op_cmpl(p_clcb, true, 0, NULL);
            break;

        case GATT_UUID_GAP_DEVICE_NAME:
            GAP_TRACE_EVENT ("GATT_UUID_GAP_DEVICE_NAME");
            len = (uint16_t)strlen((char *)pp);
            if (len > GAP_CHAR_DEV_NAME_SIZE)
                len = GAP_CHAR_DEV_NAME_SIZE;
            gap_ble_cl_op_cmpl(p_clcb, true, len, pp);
            break;

        case GATT_UUID_GAP_CENTRAL_ADDR_RESOL:
            gap_ble_cl_op_cmpl(p_clcb, true, 1, pp);
            break;
    }
}


/*******************************************************************************
**
** Function         gap_ble_accept_cl_operation
**
** Description      Start a process to read peer address resolution capability
**
** Returns          true if request accepted
**
*******************************************************************************/
bool    gap_ble_accept_cl_operation(BD_ADDR peer_bda, uint16_t uuid, tGAP_BLE_CMPL_CBACK *p_cback)
{
    tGAP_CLCB *p_clcb;
    bool    started = false;

    if (p_cback == NULL && uuid != GATT_UUID_GAP_PREF_CONN_PARAM)
        return(started);

    if ((p_clcb = gap_find_clcb_by_bd_addr (peer_bda)) == NULL)
    {
        if ((p_clcb = gap_clcb_alloc(peer_bda)) == NULL)
        {
            GAP_TRACE_ERROR("gap_ble_accept_cl_operation max connection reached");
            return started;
        }
    }

    GAP_TRACE_EVENT ("%s() - BDA: %08x%04x  cl_op_uuid: 0x%04x",
                      __func__,
                      (peer_bda[0]<<24)+(peer_bda[1]<<16)+(peer_bda[2]<<8)+peer_bda[3],
                      (peer_bda[4]<<8)+peer_bda[5], uuid);

    if (GATT_GetConnIdIfConnected(gap_cb.gatt_if, peer_bda, &p_clcb->conn_id, BT_TRANSPORT_LE))
        p_clcb->connected = true;

    /* hold the link here */
    if (!GATT_Connect(gap_cb.gatt_if, p_clcb->bda, true, BT_TRANSPORT_LE, false))
        return started;

    /* enqueue the request */
    gap_ble_enqueue_request(p_clcb, uuid, p_cback);

    if (p_clcb->connected && p_clcb->cl_op_uuid == 0)
        started = gap_ble_send_cl_read_request(p_clcb);
    else /* wait for connection up or pending operation to finish */
        started = true;

   return started;
}
/*******************************************************************************
**
** Function         GAP_BleReadPeerPrefConnParams
**
** Description      Start a process to read a connected peripheral's preferred
**                  connection parameters
**
** Returns          true if read started, else false if GAP is busy
**
*******************************************************************************/
bool    GAP_BleReadPeerPrefConnParams (BD_ADDR peer_bda)
{
    return gap_ble_accept_cl_operation (peer_bda, GATT_UUID_GAP_PREF_CONN_PARAM, NULL);
}

/*******************************************************************************
**
** Function         GAP_BleReadPeerDevName
**
** Description      Start a process to read a connected peripheral's device name.
**
** Returns          true if request accepted
**
*******************************************************************************/
bool    GAP_BleReadPeerDevName (BD_ADDR peer_bda, tGAP_BLE_CMPL_CBACK *p_cback)
{
    return gap_ble_accept_cl_operation (peer_bda, GATT_UUID_GAP_DEVICE_NAME, p_cback);
}

/*******************************************************************************
**
** Function         GAP_BleReadPeerAddressResolutionCap
**
** Description      Start a process to read peer address resolution capability
**
** Returns          true if request accepted
**
*******************************************************************************/
bool    GAP_BleReadPeerAddressResolutionCap (BD_ADDR peer_bda, tGAP_BLE_CMPL_CBACK *p_cback)
{
    return gap_ble_accept_cl_operation(peer_bda, GATT_UUID_GAP_CENTRAL_ADDR_RESOL, p_cback);
}

/*******************************************************************************
**
** Function         GAP_BleCancelReadPeerDevName
**
** Description      Cancel reading a peripheral's device name.
**
** Returns          true if request accepted
**
*******************************************************************************/
bool    GAP_BleCancelReadPeerDevName (BD_ADDR peer_bda)
{
    tGAP_CLCB *p_clcb = gap_find_clcb_by_bd_addr (peer_bda);

    GAP_TRACE_EVENT ("GAP_BleCancelReadPeerDevName() - BDA: %08x%04x  cl_op_uuid: 0x%04x",
                      (peer_bda[0]<<24)+(peer_bda[1]<<16)+(peer_bda[2]<<8)+peer_bda[3],
                      (peer_bda[4]<<8)+peer_bda[5], (p_clcb == NULL)? 0 : p_clcb->cl_op_uuid);

    if (p_clcb == NULL)
    {
        GAP_TRACE_ERROR ("Cannot cancel current op is not get dev name");
        return false;
    }

    if (!p_clcb->connected)
    {
        if (!GATT_CancelConnect(gap_cb.gatt_if, peer_bda, true))
        {
            GAP_TRACE_ERROR ("Cannot cancel where No connection id");
            return false;
        }
    }

    gap_ble_cl_op_cmpl(p_clcb, false, 0, NULL);

    return(true);
}

#endif  /* BLE_INCLUDED */