Bluetooth inquiryプロセスのコマンド

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Androidの上のBluetooth inquiryはインタフェースを設定し、Bluetoothを開くと周辺のBluetoothデバイスを自動的に検索し、最終的にプロトコルスタックのstart_に呼び出されます.discoveryインタフェース、この文章はインタフェースの呼び出しプロセスとcontrollerとのインタラクションプロセスを分析します.
static int start_discovery(void)
{
    /* sanity check */
    if (interface_ready() == FALSE)
        return BT_STATUS_NOT_READY;
    return btif_dm_start_discovery();
}

 
bt_status_t btif_dm_start_discovery(void)
{
    tBTA_DM_INQ inq_params;
    tBTA_SERVICE_MASK services = 0;
    tBTA_DM_BLE_PF_FILT_PARAMS adv_filt_param;

#if (defined(BLE_INCLUDED) && (BLE_INCLUDED == TRUE))
    memset(&adv_filt_param, 0, sizeof(tBTA_DM_BLE_PF_FILT_PARAMS));
    /* Cleanup anything remaining on index 0 */
    BTA_DmBleScanFilterSetup(BTA_DM_BLE_SCAN_COND_DELETE, 0, &adv_filt_param, NULL,
                             bte_scan_filt_param_cfg_evt, 0);

    /* Add an allow-all filter on index 0*/
    adv_filt_param.dely_mode = IMMEDIATE_DELY_MODE;
    adv_filt_param.feat_seln = ALLOW_ALL_FILTER;
    adv_filt_param.filt_logic_type = BTA_DM_BLE_PF_FILT_LOGIC_OR;
    adv_filt_param.list_logic_type = BTA_DM_BLE_PF_LIST_LOGIC_OR;
    adv_filt_param.rssi_low_thres = LOWEST_RSSI_VALUE;
    adv_filt_param.rssi_high_thres = LOWEST_RSSI_VALUE;
    BTA_DmBleScanFilterSetup(BTA_DM_BLE_SCAN_COND_ADD, 0, &adv_filt_param, NULL,
                             bte_scan_filt_param_cfg_evt, 0);

    /* TODO: Do we need to handle multiple inquiries at the same time? */

    /* Set inquiry params and call API */
    inq_params.mode = BTA_DM_GENERAL_INQUIRY|BTA_BLE_GENERAL_INQUIRY;//  inquiry  ,ble bredr
#else
    inq_params.mode = BTA_DM_GENERAL_INQUIRY;
#endif
    inq_params.duration = BTIF_DM_DEFAULT_INQ_MAX_DURATION;//      

    inq_params.max_resps = BTIF_DM_DEFAULT_INQ_MAX_RESULTS;//        response  
    inq_params.report_dup = TRUE;

    inq_params.filter_type = BTA_DM_INQ_CLR;//0
    /* TODO: Filter device by BDA needs to be implemented here */

    /* Will be enabled to TRUE once inquiry busy level has been received */
    btif_dm_inquiry_in_progress = FALSE;
    /* find nearby devices */
    BTA_DmSearch(&inq_params, services, bte_search_devices_evt);//    
    return BT_STATUS_SUCCESS;
}

 
上のコードの主な仕事は、関連する検索のパラメータを設定し、BTA_を呼び出すことです.DmSearch(&inq_params, services, bte_search_devices_evt); を選択して設定できます.
ここでは改めて送信BTAを整理しますDmSearchのパラメータ:
    inq_params.mode = BTA_DM_GENERAL_INQUIRY|BTA_BLE_GENERAL_INQUIRY;
    inq_params.duration = BTIF_DM_DEFAULT_INQ_MAX_DURATION;
    inq_params.max_resps = BTIF_DM_DEFAULT_INQ_MAX_RESULTS;
    inq_params.report_dup = TRUE;
    inq_params.filter_type = BTA_DM_INQ_CLR;//0

    tBTA_SERVICE_MASK services = 0;

    bte_search_devices_evt        ,     btif_dm.c,       
    bta_dm_search_cb.p_search_cback = bte_search_devices_evt

 
BTAを見てみましょうDmSearchの具体的な実装
/*******************************************************************************
**
** Function         BTA_DmSearch
**
** Description      This function searches for peer Bluetooth devices. It performs
**                  an inquiry and gets the remote name for devices. Service
**                  discovery is done if services is non zero
**
**
** Returns          void
**
*******************************************************************************/
void BTA_DmSearch(tBTA_DM_INQ *p_dm_inq, tBTA_SERVICE_MASK services, tBTA_DM_SEARCH_CBACK *p_cback)
{
    tBTA_DM_API_SEARCH    *p_msg;
    if ((p_msg = (tBTA_DM_API_SEARCH *) GKI_getbuf(sizeof(tBTA_DM_API_SEARCH))) != NULL)
    {
        memset(p_msg, 0, sizeof(tBTA_DM_API_SEARCH));
        p_msg->hdr.event = BTA_DM_API_SEARCH_EVT;
        memcpy(&p_msg->inq_params, p_dm_inq, sizeof(tBTA_DM_INQ));
        p_msg->services = services;
        p_msg->p_cback = p_cback;
        p_msg->rs_res  = BTA_DM_RS_NONE;
        bta_sys_sendmsg(p_msg);
    }

}

 
ここで発見したのはmsgを組み立ててbtuスレッド処理に送信し、ここでbtuスレッドに送信するパラメータを整理することです.
p_msg->hdr.event = BTA_DM_API_SEARCH_EVT; memcpy(&p_msg->inq_params, p_dm_inq, sizeof(tBTA_DM_INQ)); 上に与えられたパラメータp_msg->services = services;//service = 0 p_msg->p_cback = p_cback;//bte_search_devices_evt
p_msg->rs_res = BTA_DM_RS_NONE;
検索してみましょうBTA_DM_API_SEARCH_EVTが実行する関数:bta_dm_search_start 
/*******************************************************************************
**
** Function         bta_dm_search_start
**
** Description      Starts an inquiry
**
**
** Returns          void
**
*******************************************************************************/
void bta_dm_search_start (tBTA_DM_MSG *p_data)
{
    tBTM_INQUIRY_CMPL result;

#if (BLE_INCLUDED == TRUE && BTA_GATT_INCLUDED == TRUE)
    UINT16 len = (UINT16)(sizeof(tBT_UUID) * p_data->search.num_uuid);
    bta_dm_gattc_register();
#endif
    if (p_bta_dm_cfg->avoid_scatter &&
        (p_data->search.rs_res == BTA_DM_RS_NONE) && bta_dm_check_av(BTA_DM_API_SEARCH_EVT))
    {
        memcpy(&bta_dm_cb.search_msg, &p_data->search, sizeof(tBTA_DM_API_SEARCH));
        return;
    }

    BTM_ClearInqDb(NULL);
    /* save search params */
    bta_dm_search_cb.p_search_cback = p_data->search.p_cback;
    bta_dm_search_cb.services = p_data->search.services;

#if (BLE_INCLUDED == TRUE && BTA_GATT_INCLUDED == TRUE)
    utl_freebuf((void **)&bta_dm_search_cb.p_srvc_uuid);

    if ((bta_dm_search_cb.num_uuid = p_data->search.num_uuid) != 0 &&
         p_data->search.p_uuid != NULL)//           uuid,        copy bta_dm_search_cb.p_srvc_uuid
    {
        bta_dm_search_cb.p_srvc_uuid = (tBT_UUID *)GKI_getbuf(len)
        memcpy(bta_dm_search_cb.p_srvc_uuid, p_data->search.p_uuid, len);
    }
#endif
    result.status = BTM_StartInquiry(   (tBTM_INQ_PARMS*)&p_data->search.inq_params,
                        bta_dm_inq_results_cb,//          
                        (tBTM_CMPL_CB*) bta_dm_inq_cmpl_cb);//           

    if (result.status != BTM_CMD_STARTED)
    {
        result.num_resp = 0;
        bta_dm_inq_cmpl_cb ((void *)&result);//
    }
}

 
上のコードが実行されたらbtaを見てみましょうdm_search_cbの各構造の値:
 bta_dm_search_cb.p_search_cback = bte_search_devices_evt
bta_dm_search_cb.services = 0;
bta_dm_search_cb.num_uuid  =0;
bta_dm_search_cb.p_srvc_uuid = NULL;
続いてBTM_を見ていきますStartInquiryの実装は、ここで簡単に分析することができます.入力された3つのパラメータ:
最初のパラメータは、上に組み立てたinquiryに関する設定です.
2番目のパラメータはデバイス呼び出しへのスキャンです
3番目のパラメータはスキャン完了時に呼び出されます
/*******************************************************************************
**
** Function         BTM_StartInquiry
**
** Description      This function is called to start an inquiry.
**
** Parameters:      p_inqparms - pointer to the inquiry information
**                      mode - GENERAL or LIMITED inquiry, BR/LE bit mask seperately
**                      duration - length in 1.28 sec intervals (If '0', the inquiry is CANCELLED)
**                      max_resps - maximum amount of devices to search for before ending the inquiry
**                      filter_cond_type - BTM_CLR_INQUIRY_FILTER, BTM_FILTER_COND_DEVICE_CLASS, or
**                                         BTM_FILTER_COND_BD_ADDR
**                      filter_cond - value for the filter (based on filter_cond_type)
**
**                  p_results_cb   - Pointer to the callback routine which gets called
**                                upon receipt of an inquiry result. If this field is
**                                NULL, the application is not notified.
**
**                  p_cmpl_cb   - Pointer to the callback routine which gets called
**                                upon completion.  If this field is NULL, the
**                                application is not notified when completed.
** Returns          tBTM_STATUS
**                  BTM_CMD_STARTED if successfully initiated
**                  BTM_BUSY if already in progress
**                  BTM_ILLEGAL_VALUE if parameter(s) are out of range
**                  BTM_NO_RESOURCES if could not allocate resources to start the command
**                  BTM_WRONG_MODE if the device is not up.
**
*******************************************************************************/
tBTM_STATUS BTM_StartInquiry (tBTM_INQ_PARMS *p_inqparms, tBTM_INQ_RESULTS_CB *p_results_cb,
                              tBTM_CMPL_CB *p_cmpl_cb)
{
    tBTM_STATUS  status = BTM_CMD_STARTED;
    tBTM_INQUIRY_VAR_ST *p_inq = &btm_cb.btm_inq_vars;
        p_inq->scan_type = INQ_GENERAL;
...
    /* Save the inquiry parameters to be used upon the completion of setting/clearing the inquiry filter */
    p_inq->inqparms = *p_inqparms;//  inquiry   
    /* Initialize the inquiry variables */
    p_inq->state = BTM_INQ_ACTIVE_STATE;//active
    p_inq->p_inq_cmpl_cb = p_cmpl_cb;
    p_inq->p_inq_results_cb = p_results_cb;
    p_inq->inq_cmpl_info.num_resp = 0;         /* Clear the results counter */
    p_inq->inq_active = p_inqparms->mode;//0x11

/* start LE inquiry here if requested */
    if ((p_inqparms->mode & BTM_BLE_INQUIRY_MASK))
    {
         if ((status = btm_ble_start_inquiry((UINT8)(p_inqparms->mode & BTM_BLE_INQUIRY_MASK),
                                            p_inqparms->duration)) != BTM_CMD_STARTED)
        {
            BTM_TRACE_ERROR("Err Starting LE Inquiry.");
            p_inq->inqparms.mode &= ~ BTM_BLE_INQUIRY_MASK;
        }
#if (!defined(BTA_HOST_INTERLEAVE_SEARCH) || BTA_HOST_INTERLEAVE_SEARCH == FALSE)
        p_inqparms->mode &= ~BTM_BLE_INQUIRY_MASK;//  inquiry  ,mode   0
#endif
    }

    /* BR/EDR inquiry portion */
...
    /* Before beginning the inquiry the current filter must be cleared, so initiate the command */
    if ((status = btm_set_inq_event_filter (p_inqparms->filter_cond_type,
                                            &p_inqparms->filter_cond)) != BTM_CMD_STARTED)//      BRRDR   ,            ,      ,                bredr   inquiry
        p_inq->state = BTM_INQ_INACTIVE_STATE;
    return (status);
}

上のコードは主に3つのことをしました.
  • いくつかのパラメータをtBTM_に保存するINQUIRY_VAR_ST *p_inq = &btm_cb.btm_inq_varsという構造.
  • p_inq->scan_type = INQ_GENERAL;
  • p_inq->inqparms = *p_inqparms;
  • p_inq->state = BTM_INQ_ACTIVE_STATE;
  • p_inq->p_inq_cmpl_cb = p_cmpl_cb;
  • p_inq->p_inq_results_cb = p_results_cb;
  • p_inq->inq_cmpl_info.num_resp = 0;/* Clear the results counter */
  • p_inq->inq_active = p_inqparms->mode = 0x11(BLE|BREDR)

  • BLEをするinquiry:btm_ble_start_inquiry((UINT8)(p_inqparms->mode & BTM_BLE_INQUIRY_MASK),p_inqparms->duration)
  • BREDRを作るinquiry:btm_set_inq_event_filter (p_inqparms->filter_cond_type,&p_inqparms->filter_cond)

  • btm_ble_start_inquiry
    tBTM_STATUS btm_ble_start_inquiry (UINT8 mode, UINT8   duration)
    {
        tBTM_STATUS status = BTM_CMD_STARTED;
        tBTM_BLE_CB *p_ble_cb = &btm_cb.ble_ctr_cb;
        tBTM_INQUIRY_VAR_ST      *p_inq = &btm_cb.btm_inq_vars;
    ...
        if (!BTM_BLE_IS_SCAN_ACTIVE(p_ble_cb->scan_activity))//    scan     ,  scan
        {
            btsnd_hcic_ble_set_scan_params(BTM_BLE_SCAN_MODE_ACTI,//active scan
                                            BTM_BLE_LOW_LATENCY_SCAN_INT,
                                            BTM_BLE_LOW_LATENCY_SCAN_WIN,
                                            btm_cb.ble_ctr_cb.addr_mgnt_cb.own_addr_type,
                                            SP_ADV_ALL);
    #if (defined BLE_PRIVACY_SPT && BLE_PRIVACY_SPT == TRUE)
            /* enable IRK list */
            btm_ble_enable_resolving_list_for_platform(BTM_BLE_RL_SCAN);
    #endif
            p_ble_cb->inq_var.scan_duplicate_filter  = BTM_BLE_DUPLICATE_DISABLE;
            status = btm_ble_start_scan();//  scan
        }
        else if ((p_ble_cb->inq_var.scan_interval != BTM_BLE_LOW_LATENCY_SCAN_INT) ||
                (p_ble_cb->inq_var.scan_window != BTM_BLE_LOW_LATENCY_SCAN_WIN)) {//       scan   ,      scan,    scan
            btsnd_hcic_ble_set_scan_enable(BTM_BLE_SCAN_DISABLE, BTM_BLE_DUPLICATE_ENABLE);
            btsnd_hcic_ble_set_scan_params(BTM_BLE_SCAN_MODE_ACTI,
                                            BTM_BLE_LOW_LATENCY_SCAN_INT,
                                            BTM_BLE_LOW_LATENCY_SCAN_WIN,
                                            btm_cb.ble_ctr_cb.addr_mgnt_cb.own_addr_type,
                                            SP_ADV_ALL);
            btsnd_hcic_ble_set_scan_enable(BTM_BLE_SCAN_ENABLE, BTM_BLE_DUPLICATE_DISABLE);
        }
        if (status == BTM_CMD_STARTED)
        {
            p_inq->inq_active |= mode;//  
            p_ble_cb->scan_activity |= mode;
            if (duration != 0)
            {
                /* start inquiry timer */
                btu_start_timer (&p_inq->inq_timer_ent, BTU_TTYPE_BLE_INQUIRY, duration);//     ,            disable scan
            }
        }
        return status;
    }

    上のコードの論理は非常に簡単で、注意しなければならないのはp_です.inq->inq_Active|=modeとp_ble_cb->scan_activity |= mode;
    Bleのスキャンが開始され、持続時間は10 s=10*1000 msで、タイマがタイムアウトした後にscanがキャンセルされます.
    上からinquiryから送信されたble scanの優先度はまだ高く、現在のscanの動作を停止することもわかります.この時点でバックグラウンドにobserve動作がある場合は、停止されます.
    btm_set_inq_event_filter
    static tBTM_STATUS btm_set_inq_event_filter (UINT8 filter_cond_type,
                                                 tBTM_INQ_FILT_COND *p_filt_cond)
    {
    ...
        btm_cb.btm_inq_vars.inqfilt_active = TRUE;      
    
        /* Filter the inquiry results for the specified condition type and value */
        if (btsnd_hcic_set_event_filter(HCI_FILTER_INQUIRY_RESULT, filter_cond_type,
                                        p_cond, condition_length))
    
            return (BTM_CMD_STARTED);
        else
            return (BTM_NO_RESOURCES);
    }

    主にHCIを送信していますFILTER_INQUIRY_RESULT、およびステータスビットが設定されている:btm_cb.btm_inq_vars.inqfilt_active = TRUE
    検索の動作は、この関数の完了イベントで行われるに違いありません.
    static void btu_hcif_hdl_command_complete (UINT16 opcode, UINT8 *p, UINT16 evt_len,
                                               void *p_cplt_cback)
    {
        switch (opcode)
        {
            case HCI_INQUIRY_CANCEL:
                /* Tell inquiry processing that we are done */
                btm_process_cancel_complete(HCI_SUCCESS, BTM_BR_INQUIRY_MASK);
                break;
            case HCI_SET_EVENT_FILTER:
                btm_event_filter_complete (p);//     
                break;
    void btm_event_filter_complete (UINT8 *p)
    {
        UINT8            hci_status;
        tBTM_STATUS      status;
        tBTM_INQUIRY_VAR_ST *p_inq = &btm_cb.btm_inq_vars;
        tBTM_CMPL_CB   *p_cb = p_inq->p_inqfilter_cmpl_cb;
    ...
        /* Only process the inquiry filter; Ignore the connection filter until it
           is used by the upper layers */
        if (p_inq->inqfilt_active == TRUE ) //            
        {
            /* Extract the returned status from the buffer */
            STREAM_TO_UINT8 (hci_status, p);
            if (hci_status != HCI_SUCCESS)
            {
                /* If standalone operation, return the error status; if embedded in the inquiry, continue the inquiry */
                BTM_TRACE_WARNING ("BTM Warning: Set Event Filter Failed (HCI returned 0x%x)", hci_status);
                status = BTM_ERR_PROCESSING;
            }
            else
                status = BTM_SUCCESS;
    
            /* If the set filter was initiated externally (via BTM_SetInqEventFilter), call the
               callback function to notify the initiator that it has completed */
            if (p_inq->state == BTM_INQ_INACTIVE_STATE)//   active  
            {
                p_inq->inqfilt_active = FALSE;
                if (p_cb)
                    (*p_cb) (&status);
            }
            else    /* An inquiry is active (the set filter command was internally generated),
                       process the next state of the process (Set a new filter or start the inquiry). */
            {
                if(status != BTM_SUCCESS)
                {
                    /* Process the inquiry complete (Error Status) */
                    btm_process_inq_complete (BTM_ERR_PROCESSING, (UINT8)(p_inq->inqparms.mode & BTM_BR_INQUIRY_MASK));
    
                    /* btm_process_inq_complete() does not restore the following settings on periodic inquiry */
                    p_inq->inqfilt_active = FALSE;
                    p_inq->inq_active = BTM_INQUIRY_INACTIVE;
                    p_inq->state = BTM_INQ_INACTIVE_STATE;
    
                    return;
                }
    
                /* Check to see if a new filter needs to be set up */
                if (p_inq->state == BTM_INQ_CLR_FILT_STATE)
                {
                    if ((status = btm_set_inq_event_filter (p_inq->inqparms.filter_cond_type, &p_inq->inqparms.filter_cond)) == BTM_CMD_STARTED)
                    {
                        p_inq->state = BTM_INQ_SET_FILT_STATE;
                    }
                    else    /* Error setting the filter: Call the initiator's callback function to indicate a failure */
                    {
                        p_inq->inqfilt_active = FALSE;
    
                        /* Process the inquiry complete (Error Status) */
                        btm_process_inq_complete (BTM_ERR_PROCESSING, (UINT8)(p_inq->inqparms.mode & BTM_BR_INQUIRY_MASK));
                    }
                }
                else    /* Initiate the Inquiry or Periodic Inquiry */
                {
                    p_inq->state = BTM_INQ_ACTIVE_STATE;//     
                    p_inq->inqfilt_active = FALSE;//  false
                    btm_initiate_inquiry (p_inq);//    
                }
            }
        }
    }

     
    上のコードの主なことは:
    p_inq->state = BTM_INQ_ACTIVE_STATE; p_inq->inqfilt_active = FALSE; btm_initiate_inquiry (p_inq);
    続けてbtm_initiate_inquiryの実装:
    static void btm_initiate_inquiry (tBTM_INQUIRY_VAR_ST *p_inq)
    {
        const LAP       *lap;
        tBTM_INQ_PARMS  *p_inqparms = &p_inq->inqparms;
        btm_acl_update_busy_level (BTM_BLI_INQ_EVT);
    ...
        lap = (p_inq->inq_active & BTM_LIMITED_INQUIRY_ACTIVE) ? &limited_inq_lap : &general_inq_lap;//  LAP
    
        {
            btm_clr_inq_result_flt();//    
            /* Allocate memory to hold bd_addrs responding */
            if ((p_inq->p_bd_db = (tINQ_BDADDR *)GKI_getbuf(GKI_MAX_BUF_SIZE)) != NULL)
            {
                p_inq->max_bd_entries = (UINT16)(GKI_MAX_BUF_SIZE / sizeof(tINQ_BDADDR));
                memset(p_inq->p_bd_db, 0, GKI_MAX_BUF_SIZE);
    /*            BTM_TRACE_DEBUG("btm_initiate_inquiry: memory allocated for %d bdaddrs",
                                  p_inq->max_bd_entries); */
            }
    
            if (!btsnd_hcic_inquiry(*lap, p_inqparms->duration, 0))//  inquiry   
                btm_process_inq_complete (BTM_NO_RESOURCES, (UINT8)(p_inqparms->mode & BTM_BR_INQUIRY_MASK));
        }
    }

     
    上のコードではbtsnd_に重点を置いていますhcic_inquiry(*lap, p_inqparms->duration, 0) 
    その実現はcontrollerにinquiryのコマンドを送信することである.ここで、durationパラメータは10であり、対応する実際の値は10*1.28 sであり、12.8秒後にinquiry completeイベントが送信される.
    inquiryのコマンド送信プロセスはここまで分析される.
    転載先:https://www.cnblogs.com/libs-liu/p/9229253.html