/******************************************************************************
 *
 *  Copyright (C) 2010-2014 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.
 *
 ******************************************************************************/


/******************************************************************************
 *
 *  This file contains the implementation for Type 2 tag in Reader/Writer
 *  mode.
 *
 ******************************************************************************/
#include <string.h>
#include "nfc_target.h"
#include "bt_types.h"

#if (NFC_INCLUDED == TRUE)
#include "nfc_api.h"
#include "nci_hmsgs.h"
#include "rw_api.h"
#include "rw_int.h"
#include "nfc_int.h"
#include "gki.h"

/* Static local functions */
static void rw_t2t_proc_data (UINT8 conn_id, tNFC_DATA_CEVT *p_data);
static tNFC_STATUS rw_t2t_send_cmd (UINT8 opcode, UINT8 *p_dat);
static void rw_t2t_process_error (void);
static void rw_t2t_process_frame_error (void);
static void rw_t2t_handle_presence_check_rsp (tNFC_STATUS status);
static void rw_t2t_resume_op (void);

#if (BT_TRACE_VERBOSE == TRUE)
static char *rw_t2t_get_state_name (UINT8 state);
static char *rw_t2t_get_substate_name (UINT8 substate);
#endif

/*******************************************************************************
**
** Function         rw_t2t_proc_data
**
** Description      This function handles data evt received from NFC Controller.
**
** Returns          none
**
*******************************************************************************/
static void rw_t2t_proc_data (UINT8 conn_id, tNFC_DATA_CEVT *p_data)
{
    tRW_EVENT               rw_event    = RW_RAW_FRAME_EVT;
    tRW_T2T_CB              *p_t2t      = &rw_cb.tcb.t2t;
    BT_HDR                  *p_pkt      = p_data->p_data;
    BOOLEAN                 b_notify    = TRUE;
    BOOLEAN                 b_release   = TRUE;
    UINT8                   *p;
    tRW_READ_DATA           evt_data = {0, };
    tT2T_CMD_RSP_INFO       *p_cmd_rsp_info = (tT2T_CMD_RSP_INFO *) rw_cb.tcb.t2t.p_cmd_rsp_info;
    tRW_DETECT_NDEF_DATA    ndef_data;
#if (BT_TRACE_VERBOSE == TRUE)
    UINT8                   begin_state     = p_t2t->state;
#endif

    if (  (p_t2t->state == RW_T2T_STATE_IDLE)
        ||(p_cmd_rsp_info == NULL)  )
    {

#if (BT_TRACE_VERBOSE == TRUE)
        RW_TRACE_DEBUG2 ("RW T2T Raw Frame: Len [0x%X] Status [%s]", p_pkt->len, NFC_GetStatusName (p_data->status));
#else
        RW_TRACE_DEBUG2 ("RW T2T Raw Frame: Len [0x%X] Status [0x%X]", p_pkt->len, p_data->status);
#endif
        evt_data.status = p_data->status;
        evt_data.p_data = p_pkt;
        (*rw_cb.p_cback) (RW_T2T_RAW_FRAME_EVT, (tRW_DATA *)&evt_data);
        return;
    }
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
    /* Update rx stats */
    rw_main_update_rx_stats (p_pkt->len);
#endif
    /* Stop timer as response is received */
    nfc_stop_quick_timer (&p_t2t->t2_timer);

    RW_TRACE_EVENT2 ("RW RECV [%s]:0x%x RSP", t2t_info_to_str (p_cmd_rsp_info), p_cmd_rsp_info->opcode);

    if (  (  (p_pkt->len != p_cmd_rsp_info->rsp_len)
           &&(p_pkt->len != p_cmd_rsp_info->nack_rsp_len)
           &&(p_t2t->substate != RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR)  )
        ||(p_t2t->state == RW_T2T_STATE_HALT)  )
    {
#if (BT_TRACE_VERBOSE == TRUE)
        RW_TRACE_ERROR1 ("T2T Frame error. state=%s ", rw_t2t_get_state_name (p_t2t->state));
#else
        RW_TRACE_ERROR1 ("T2T Frame error. state=0x%02X command=0x%02X ", p_t2t->state);
#endif
        if (p_t2t->state != RW_T2T_STATE_HALT)
        {
            /* Retrasmit the last sent command if retry-count < max retry */
            rw_t2t_process_frame_error ();
            p_t2t->check_tag_halt = FALSE;
        }
        GKI_freebuf (p_pkt);
        return;
    }
    rw_cb.cur_retry = 0;

    /* Assume the data is just the response byte sequence */
    p = (UINT8 *) (p_pkt + 1) + p_pkt->offset;


    RW_TRACE_EVENT4 ("rw_t2t_proc_data State: %u  conn_id: %u  len: %u  data[0]: 0x%02x",
                      p_t2t->state, conn_id, p_pkt->len, *p);

    evt_data.p_data     = NULL;

    if (p_t2t->substate == RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR_SUPPORT)
    {
        /* The select process happens in two steps */
        if ((*p & 0x0f) == T2T_RSP_ACK)
        {
            if (rw_t2t_sector_change (p_t2t->select_sector) == NFC_STATUS_OK)
                b_notify = FALSE;
            else
                evt_data.status = NFC_STATUS_FAILED;
        }
        else
        {
            RW_TRACE_EVENT1 ("rw_t2t_proc_data - Received NACK response(0x%x) to SEC-SELCT CMD", (*p & 0x0f));
            evt_data.status = NFC_STATUS_REJECTED;
        }
    }
    else if (p_t2t->substate == RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR)
    {
        evt_data.status = NFC_STATUS_FAILED;
    }
    else if (  (p_pkt->len != p_cmd_rsp_info->rsp_len)
             ||((p_cmd_rsp_info->opcode == T2T_CMD_WRITE) && ((*p & 0x0f) != T2T_RSP_ACK))  )
    {
        /* Received NACK response */
        evt_data.p_data = p_pkt;
        if (p_t2t->state == RW_T2T_STATE_READ)
            b_release = FALSE;

        RW_TRACE_EVENT1 ("rw_t2t_proc_data - Received NACK response(0x%x)", (*p & 0x0f));

        if (!p_t2t->check_tag_halt)
        {
            /* Just received first NACK. Retry just one time to find if tag went in to HALT State */
            b_notify =  FALSE;
            rw_t2t_process_error ();
            /* Assume Tag is in HALT State, untill we get response to retry command */
            p_t2t->check_tag_halt = TRUE;
        }
        else
        {
            p_t2t->check_tag_halt = FALSE;
            /* Got consecutive NACK so tag not really halt after first NACK, but current operation failed */
            evt_data.status = NFC_STATUS_FAILED;
        }
    }
    else
    {
        /* If the response length indicates positive response or cannot be known from length then assume success */
        evt_data.status  = NFC_STATUS_OK;
        p_t2t->check_tag_halt = FALSE;

        /* The response data depends on what the current operation was */
        switch (p_t2t->state)
        {
        case RW_T2T_STATE_CHECK_PRESENCE:
            b_notify = FALSE;
            rw_t2t_handle_presence_check_rsp (NFC_STATUS_OK);
            break;

        case RW_T2T_STATE_READ:
            evt_data.p_data = p_pkt;
            b_release = FALSE;
            if (p_t2t->block_read == 0)
            {
                p_t2t->b_read_hdr = TRUE;
                memcpy (p_t2t->tag_hdr,  p, T2T_READ_DATA_LEN);
            }
            break;

        case RW_T2T_STATE_WRITE:
            /* Write operation completed successfully */
            break;

        default:
            /* NDEF/other Tlv Operation/Format-Tag/Config Tag as Read only */
            b_notify = FALSE;
            rw_t2t_handle_rsp (p);
            break;
        }
    }

    if (b_notify)
    {
        rw_event = rw_t2t_info_to_event (p_cmd_rsp_info);

        if (rw_event == RW_T2T_NDEF_DETECT_EVT)
        {
            ndef_data.status    = evt_data.status;
            ndef_data.protocol  = NFC_PROTOCOL_T2T;
            ndef_data.flags     = RW_NDEF_FL_UNKNOWN;
            if (p_t2t->substate == RW_T2T_SUBSTATE_WAIT_READ_LOCKS)
                ndef_data.flags = RW_NDEF_FL_FORMATED;
            ndef_data.max_size  = 0;
            ndef_data.cur_size  = 0;
            /* Move back to idle state */
            rw_t2t_handle_op_complete ();
            (*rw_cb.p_cback) (rw_event, (tRW_DATA *) &ndef_data);
        }
        else
        {
            /* Move back to idle state */
            rw_t2t_handle_op_complete ();
            (*rw_cb.p_cback) (rw_event, (tRW_DATA *) &evt_data);
        }
    }

    if (b_release)
        GKI_freebuf (p_pkt);

#if (BT_TRACE_VERBOSE == TRUE)
    if (begin_state != p_t2t->state)
    {
        RW_TRACE_DEBUG2 ("RW T2T state changed:<%s> -> <%s>",
                          rw_t2t_get_state_name (begin_state),
                          rw_t2t_get_state_name (p_t2t->state));
    }
#endif
}

/*******************************************************************************
**
** Function         rw_t2t_conn_cback
**
** Description      This callback function receives events/data from NFCC.
**
** Returns          none
**
*******************************************************************************/
void rw_t2t_conn_cback (UINT8 conn_id, tNFC_CONN_EVT event, tNFC_CONN *p_data)
{
    tRW_T2T_CB  *p_t2t  = &rw_cb.tcb.t2t;
    tRW_READ_DATA       evt_data;

    RW_TRACE_DEBUG2 ("rw_t2t_conn_cback: conn_id=%i, evt=%i", conn_id, event);
    /* Only handle static conn_id */
    if (conn_id != NFC_RF_CONN_ID)
    {
        return;
    }

    switch (event)
    {
    case NFC_CONN_CREATE_CEVT:
    case NFC_CONN_CLOSE_CEVT:
        break;

    case NFC_DEACTIVATE_CEVT:
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
        /* Display stats */
        rw_main_log_stats ();
#endif
        /* Stop t2t timer (if started) */
        nfc_stop_quick_timer (&p_t2t->t2_timer);

        /* Free cmd buf for retransmissions */
        if (p_t2t->p_cur_cmd_buf)
        {
            GKI_freebuf (p_t2t->p_cur_cmd_buf);
            p_t2t->p_cur_cmd_buf = NULL;
        }
        /* Free cmd buf used to hold command before sector change */
        if (p_t2t->p_sec_cmd_buf)
        {
            GKI_freebuf (p_t2t->p_sec_cmd_buf);
            p_t2t->p_sec_cmd_buf = NULL;
        }

        p_t2t->state = RW_T2T_STATE_NOT_ACTIVATED;
        NFC_SetStaticRfCback (NULL);
        break;

    case NFC_DATA_CEVT:
        if (  (p_data != NULL)
            &&(  (p_data->data.status == NFC_STATUS_OK)
               ||(p_data->data.status == NFC_STATUS_CONTINUE)  )  )
        {
            rw_t2t_proc_data (conn_id, &(p_data->data));
            break;
        }
        /* Data event with error status...fall through to NFC_ERROR_CEVT case */

    case NFC_ERROR_CEVT:
        if (  (p_t2t->state == RW_T2T_STATE_NOT_ACTIVATED)
            ||(p_t2t->state == RW_T2T_STATE_IDLE)
            ||(p_t2t->state == RW_T2T_STATE_HALT)  )
        {
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
            rw_main_update_trans_error_stats ();
#endif  /* RW_STATS_INCLUDED */
            if (event == NFC_ERROR_CEVT)
                evt_data.status = (tNFC_STATUS) (*(UINT8*) p_data);
            else if (p_data)
                evt_data.status = p_data->status;
            else
                evt_data.status = NFC_STATUS_FAILED;

            evt_data.p_data = NULL;
            (*rw_cb.p_cback) (RW_T2T_INTF_ERROR_EVT, (tRW_DATA *) &evt_data);
            break;
        }
        nfc_stop_quick_timer (&p_t2t->t2_timer);
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
        rw_main_update_trans_error_stats ();
#endif
        if (p_t2t->state == RW_T2T_STATE_CHECK_PRESENCE)
        {
            if (p_t2t->check_tag_halt)
            {
                p_t2t->state = RW_T2T_STATE_HALT;
                rw_t2t_handle_presence_check_rsp (NFC_STATUS_REJECTED);
            }
            else
            {
                /* Move back to idle state */
                rw_t2t_handle_presence_check_rsp (NFC_STATUS_FAILED);
            }
        }
        else
        {
            rw_t2t_process_error ();
        }
        break;

    default:
        break;

    }
}

/*******************************************************************************
**
** Function         rw_t2t_send_cmd
**
** Description      This function composes a Type 2 Tag command and send it via
**                  NCI to NFCC.
**
** Returns          NFC_STATUS_OK if the command is successfuly sent to NCI
**                  otherwise, error status
**
*******************************************************************************/
tNFC_STATUS rw_t2t_send_cmd (UINT8 opcode, UINT8 *p_dat)
{
    tNFC_STATUS             status  = NFC_STATUS_FAILED;
    tRW_T2T_CB              *p_t2t  = &rw_cb.tcb.t2t;
    const tT2T_CMD_RSP_INFO *p_cmd_rsp_info = t2t_cmd_to_rsp_info (opcode);
    BT_HDR                  *p_data;
    UINT8                   *p;

    if (p_cmd_rsp_info)
    {
        /* a valid opcode for RW */
        p_data = (BT_HDR *) GKI_getpoolbuf (NFC_RW_POOL_ID);
        if (p_data)
        {
            p_t2t->p_cmd_rsp_info   = (tT2T_CMD_RSP_INFO *) p_cmd_rsp_info;
            p_data->offset  = NCI_MSG_OFFSET_SIZE + NCI_DATA_HDR_SIZE;
            p               = (UINT8 *) (p_data + 1) + p_data->offset;

            UINT8_TO_STREAM (p, opcode);

            if (p_dat)
            {
                ARRAY_TO_STREAM (p, p_dat, (p_cmd_rsp_info->cmd_len - 1));
            }

            p_data->len     = p_cmd_rsp_info->cmd_len;

            /* Indicate first attempt to send command, back up cmd buffer in case needed for retransmission */
            rw_cb.cur_retry = 0;
            memcpy (p_t2t->p_cur_cmd_buf, p_data, sizeof (BT_HDR) + p_data->offset + p_data->len);

#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
            /* Update stats */
            rw_main_update_tx_stats (p_data->len, FALSE);
#endif
            RW_TRACE_EVENT2 ("RW SENT [%s]:0x%x CMD", t2t_info_to_str (p_cmd_rsp_info), p_cmd_rsp_info->opcode);

            if ((status = NFC_SendData (NFC_RF_CONN_ID, p_data)) == NFC_STATUS_OK)
            {
                nfc_start_quick_timer (&p_t2t->t2_timer, NFC_TTYPE_RW_T2T_RESPONSE,
                       (RW_T2T_TOUT_RESP*QUICK_TIMER_TICKS_PER_SEC) / 1000);
            }
            else
            {
#if (BT_TRACE_VERBOSE == TRUE)
                RW_TRACE_ERROR2 ("T2T NFC Send data failed. state=%s substate=%s ", rw_t2t_get_state_name (p_t2t->state), rw_t2t_get_substate_name (p_t2t->substate));
#else
                RW_TRACE_ERROR2 ("T2T NFC Send data failed. state=0x%02X substate=0x%02X ", p_t2t->state, p_t2t->substate);
#endif
            }
        }
        else
        {
            status = NFC_STATUS_NO_BUFFERS;
        }
    }
    return status;
}

/*******************************************************************************
**
** Function         rw_t2t_process_timeout
**
** Description      handles timeout event
**
** Returns          none
**
*******************************************************************************/
void rw_t2t_process_timeout (TIMER_LIST_ENT *p_tle)
{
    tRW_READ_DATA       evt_data;
    tRW_T2T_CB          *p_t2t          = &rw_cb.tcb.t2t;

    if (p_t2t->state == RW_T2T_STATE_CHECK_PRESENCE)
    {
        if (p_t2t->check_tag_halt)
        {
            p_t2t->state = RW_T2T_STATE_HALT;
            rw_t2t_handle_presence_check_rsp (NFC_STATUS_REJECTED);
        }
        else
        {
            /* Move back to idle state */
            rw_t2t_handle_presence_check_rsp (NFC_STATUS_FAILED);
        }
        return;
    }

    if (p_t2t->substate == RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR)
    {
        p_t2t->sector   = p_t2t->select_sector;
        /* Here timeout is an acknowledgment for successfull sector change */
        if (p_t2t->state == RW_T2T_STATE_SELECT_SECTOR)
        {
            /* Notify that select sector op is successfull */
            rw_t2t_handle_op_complete ();
            evt_data.status = NFC_STATUS_OK;
            evt_data.p_data = NULL;
            (*rw_cb.p_cback) (RW_T2T_SELECT_CPLT_EVT, (tRW_DATA *) &evt_data);
        }
        else
        {
            /* Resume operation from where we stopped before sector change */
            rw_t2t_resume_op ();
        }
    }
    else if (p_t2t->state != RW_T2T_STATE_IDLE)
    {
#if (BT_TRACE_VERBOSE == TRUE)
        RW_TRACE_ERROR1 ("T2T timeout. state=%s ", rw_t2t_get_state_name (p_t2t->state));
#else
        RW_TRACE_ERROR1 ("T2T timeout. state=0x%02X ", p_t2t->state);
#endif
        /* Handle timeout error as no response to the command sent */
        rw_t2t_process_error ();
    }
}

/*******************************************************************************
**
** Function         rw_t2t_process_frame_error
**
** Description      handles frame crc error
**
** Returns          none
**
*******************************************************************************/
static void rw_t2t_process_frame_error (void)
{
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
    /* Update stats */
    rw_main_update_crc_error_stats ();
#endif
    /* Process the error */
    rw_t2t_process_error ();
}

/*******************************************************************************
**
** Function         rw_t2t_process_error
**
** Description      Process error including Timeout, Frame error. This function
**                  will retry atleast till RW_MAX_RETRIES before give up and
**                  sending negative notification to upper layer
**
** Returns          none
**
*******************************************************************************/
static void rw_t2t_process_error (void)
{
    tRW_READ_DATA           evt_data;
    tRW_EVENT               rw_event;
    BT_HDR                  *p_cmd_buf;
    tRW_T2T_CB              *p_t2t          = &rw_cb.tcb.t2t;
    tT2T_CMD_RSP_INFO       *p_cmd_rsp_info = (tT2T_CMD_RSP_INFO *) rw_cb.tcb.t2t.p_cmd_rsp_info;
    tRW_DETECT_NDEF_DATA    ndef_data;

    RW_TRACE_DEBUG1 ("rw_t2t_process_error () State: %u", p_t2t->state);

    /* Retry sending command if retry-count < max */
    if (  (!p_t2t->check_tag_halt)
        &&(rw_cb.cur_retry < RW_MAX_RETRIES)  )
    {
        /* retry sending the command */
        rw_cb.cur_retry++;

        RW_TRACE_DEBUG2 ("T2T retransmission attempt %i of %i", rw_cb.cur_retry, RW_MAX_RETRIES);

        /* allocate a new buffer for message */
        if ((p_cmd_buf = (BT_HDR *) GKI_getpoolbuf (NFC_RW_POOL_ID)) != NULL)
        {
            memcpy (p_cmd_buf, p_t2t->p_cur_cmd_buf, sizeof (BT_HDR) + p_t2t->p_cur_cmd_buf->offset + p_t2t->p_cur_cmd_buf->len);
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
            /* Update stats */
            rw_main_update_tx_stats (p_cmd_buf->len, TRUE);
#endif
            if (NFC_SendData (NFC_RF_CONN_ID, p_cmd_buf) == NFC_STATUS_OK)
            {
                /* Start timer for waiting for response */
                nfc_start_quick_timer (&p_t2t->t2_timer, NFC_TTYPE_RW_T2T_RESPONSE,
                                       (RW_T2T_TOUT_RESP * QUICK_TIMER_TICKS_PER_SEC) / 1000);

                return;
            }
        }
    }
    else
    {
        if (p_t2t->check_tag_halt)
        {
            RW_TRACE_DEBUG0 ("T2T Went to HALT State!");
        }
        else
        {
            RW_TRACE_DEBUG1 ("T2T maximum retransmission attempts reached (%i)", RW_MAX_RETRIES);
        }
    }
    rw_event = rw_t2t_info_to_event (p_cmd_rsp_info);
#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
    /* update failure count */
    rw_main_update_fail_stats ();
#endif
    if (p_t2t->check_tag_halt)
    {
        evt_data.status = NFC_STATUS_REJECTED;
        p_t2t->state    = RW_T2T_STATE_HALT;
    }
    else
    {
        evt_data.status = NFC_STATUS_TIMEOUT;
    }

    if (rw_event == RW_T2T_NDEF_DETECT_EVT)
    {
        ndef_data.status    = evt_data.status;
        ndef_data.protocol  = NFC_PROTOCOL_T2T;
        ndef_data.flags     = RW_NDEF_FL_UNKNOWN;
        if (p_t2t->substate == RW_T2T_SUBSTATE_WAIT_READ_LOCKS)
            ndef_data.flags = RW_NDEF_FL_FORMATED;
        ndef_data.max_size  = 0;
        ndef_data.cur_size  = 0;
        /* If not Halt move to idle state */
        rw_t2t_handle_op_complete ();

        (*rw_cb.p_cback) (rw_event, (tRW_DATA *) &ndef_data);
    }
    else
    {
        evt_data.p_data = NULL;
        /* If activated and not Halt move to idle state */
        if (p_t2t->state != RW_T2T_STATE_NOT_ACTIVATED)
            rw_t2t_handle_op_complete ();

        p_t2t->substate = RW_T2T_SUBSTATE_NONE;
        (*rw_cb.p_cback) (rw_event, (tRW_DATA *) &evt_data);
    }
}

/*****************************************************************************
**
** Function         rw_t2t_handle_presence_check_rsp
**
** Description      Handle response to presence check
**
** Returns          Nothing
**
*****************************************************************************/
void rw_t2t_handle_presence_check_rsp (tNFC_STATUS status)
{
    tRW_READ_DATA   evt_data;

    /* Notify, Tag is present or not */
    evt_data.status = status;
    rw_t2t_handle_op_complete ();

    (*rw_cb.p_cback) (RW_T2T_PRESENCE_CHECK_EVT, (tRW_DATA *) &evt_data);
}

/*******************************************************************************
**
** Function         rw_t2t_resume_op
**
** Description      This function will continue operation after moving to new
**                  sector
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
static void rw_t2t_resume_op (void)
{
    tRW_T2T_CB          *p_t2t = &rw_cb.tcb.t2t;
    tRW_READ_DATA       evt_data;
    BT_HDR              *p_cmd_buf;
    tRW_EVENT           event;
    const tT2T_CMD_RSP_INFO   *p_cmd_rsp_info = (tT2T_CMD_RSP_INFO *) rw_cb.tcb.t2t.p_cmd_rsp_info;
    UINT8               *p;

    /* Move back to the substate where we were before changing sector */
    p_t2t->substate = p_t2t->prev_substate;

    p              = (UINT8 *) (p_t2t->p_sec_cmd_buf + 1) + p_t2t->p_sec_cmd_buf->offset;
    p_cmd_rsp_info = t2t_cmd_to_rsp_info ((UINT8) *p);
    p_t2t->p_cmd_rsp_info   = (tT2T_CMD_RSP_INFO *) p_cmd_rsp_info;

    /* allocate a new buffer for message */
    if ((p_cmd_buf = (BT_HDR *) GKI_getpoolbuf (NFC_RW_POOL_ID)) != NULL)
    {
        memcpy (p_cmd_buf, p_t2t->p_sec_cmd_buf, sizeof (BT_HDR) + p_t2t->p_sec_cmd_buf->offset + p_t2t->p_sec_cmd_buf->len);
        memcpy (p_t2t->p_cur_cmd_buf, p_t2t->p_sec_cmd_buf, sizeof (BT_HDR) + p_t2t->p_sec_cmd_buf->offset + p_t2t->p_sec_cmd_buf->len);

#if (defined (RW_STATS_INCLUDED) && (RW_STATS_INCLUDED == TRUE))
        /* Update stats */
         rw_main_update_tx_stats (p_cmd_buf->len, TRUE);
#endif
        if (NFC_SendData (NFC_RF_CONN_ID, p_cmd_buf) == NFC_STATUS_OK)
        {
            /* Start timer for waiting for response */
            nfc_start_quick_timer (&p_t2t->t2_timer, NFC_TTYPE_RW_T2T_RESPONSE,
                                   (RW_T2T_TOUT_RESP * QUICK_TIMER_TICKS_PER_SEC) / 1000);
        }
        else
        {
            /* failure - could not send buffer */
            evt_data.p_data = NULL;
            evt_data.status = NFC_STATUS_FAILED;
            event = rw_t2t_info_to_event (p_cmd_rsp_info);
            rw_t2t_handle_op_complete ();
            (*rw_cb.p_cback) (event, (tRW_DATA *) &evt_data);
        }
    }
}

/*******************************************************************************
**
** Function         rw_t2t_sector_change
**
** Description      This function issues Type 2 Tag SECTOR-SELECT command
**                  packet 1.
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
tNFC_STATUS rw_t2t_sector_change (UINT8 sector)
{
    tNFC_STATUS status;
    BT_HDR      *p_data;
    UINT8       *p;
    tRW_T2T_CB  *p_t2t = &rw_cb.tcb.t2t;

    if ((p_data = (BT_HDR *) GKI_getpoolbuf (NFC_RW_POOL_ID)) == NULL)
    {
        RW_TRACE_ERROR0 ("rw_t2t_sector_change - No buffer");
         return (NFC_STATUS_NO_BUFFERS);
    }

    p_data->offset = NCI_MSG_OFFSET_SIZE + NCI_DATA_HDR_SIZE;
    p = (UINT8 *) (p_data + 1) + p_data->offset;

    UINT8_TO_BE_STREAM (p, sector);
    UINT8_TO_BE_STREAM (p, 0x00);
    UINT8_TO_BE_STREAM (p, 0x00);
    UINT8_TO_BE_STREAM (p, 0x00);

    p_data->len = 4;

    if ((status = NFC_SendData (NFC_RF_CONN_ID , p_data)) == NFC_STATUS_OK)
    {
        /* Passive rsp command and suppose not to get response to this command */
        p_t2t->p_cmd_rsp_info = NULL;
        p_t2t->substate       = RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR;

        RW_TRACE_EVENT0 ("rw_t2t_sector_change Sent Second Command");
        nfc_start_quick_timer (&p_t2t->t2_timer, NFC_TTYPE_RW_T2T_RESPONSE,
                               (RW_T2T_SEC_SEL_TOUT_RESP * QUICK_TIMER_TICKS_PER_SEC) / 1000);
    }
    else
    {
        RW_TRACE_ERROR1 ("rw_t2t_sector_change Send failed at rw_t2t_send_cmd, error: %u", status);
    }

    return status;
}

/*******************************************************************************
**
** Function         rw_t2t_read
**
** Description      This function issues Type 2 Tag READ command for the
**                  specified block. If the specified block is in different
**                  sector then it first sends command to move to new sector
**                  and after the tag moves to new sector it issues the read
**                  command for the block.
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
tNFC_STATUS rw_t2t_read (UINT16 block)
{
    tNFC_STATUS status;
    UINT8       *p;
    tRW_T2T_CB  *p_t2t = &rw_cb.tcb.t2t;
    UINT8       sector_byte2[1];
    UINT8       read_cmd[1];


    read_cmd[0] = block % T2T_BLOCKS_PER_SECTOR;
    if (p_t2t->sector != block/T2T_BLOCKS_PER_SECTOR)
    {
        sector_byte2[0] = 0xFF;
        /* First Move to new sector before sending Read command */
        if ((status = rw_t2t_send_cmd (T2T_CMD_SEC_SEL,sector_byte2)) == NFC_STATUS_OK)
        {
            /* Prepare command that needs to be sent after sector change op is completed */
            p_t2t->select_sector         = (UINT8) (block/T2T_BLOCKS_PER_SECTOR);
            p_t2t->p_sec_cmd_buf->offset = NCI_MSG_OFFSET_SIZE + NCI_DATA_HDR_SIZE;

            p = (UINT8 *) (p_t2t->p_sec_cmd_buf + 1) + p_t2t->p_sec_cmd_buf->offset;
            UINT8_TO_BE_STREAM (p, T2T_CMD_READ);
            UINT8_TO_BE_STREAM (p, read_cmd[0]);
            p_t2t->p_sec_cmd_buf->len = 2;
            p_t2t->block_read = block;

            /* Backup the current substate to move back to this substate after changing sector */
            p_t2t->prev_substate = p_t2t->substate;
            p_t2t->substate      = RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR_SUPPORT;
            return NFC_STATUS_OK;
        }
        return NFC_STATUS_FAILED;
    }

    /* Send Read command as sector change is not needed */
    if ((status = rw_t2t_send_cmd (T2T_CMD_READ, (UINT8 *) read_cmd)) == NFC_STATUS_OK)
    {
        p_t2t->block_read = block;
        RW_TRACE_EVENT1 ("rw_t2t_read Sent Command for Block: %u", block);
    }

    return status;
}

/*******************************************************************************
**
** Function         rw_t2t_write
**
** Description      This function issues Type 2 Tag WRITE command for the
**                  specified block.  If the specified block is in different
**                  sector then it first sends command to move to new sector
**                  and after the tag moves to new sector it issues the write
**                  command for the block.
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
tNFC_STATUS rw_t2t_write (UINT16 block, UINT8 *p_write_data)
{
    tNFC_STATUS status;
    UINT8       *p;
    tRW_T2T_CB  *p_t2t = &rw_cb.tcb.t2t;
    UINT8       write_cmd[T2T_WRITE_DATA_LEN + 1];
    UINT8       sector_byte2[1];

    p_t2t->block_written = block;
    write_cmd[0] = (UINT8) (block%T2T_BLOCKS_PER_SECTOR);
    memcpy (&write_cmd[1], p_write_data, T2T_WRITE_DATA_LEN);

    if (p_t2t->sector != block/T2T_BLOCKS_PER_SECTOR)
    {
        sector_byte2[0] = 0xFF;
        /* First Move to new sector before sending Write command */
        if ((status = rw_t2t_send_cmd (T2T_CMD_SEC_SEL, sector_byte2)) == NFC_STATUS_OK)
        {
            /* Prepare command that needs to be sent after sector change op is completed */
            p_t2t->select_sector         = (UINT8) (block/T2T_BLOCKS_PER_SECTOR);
            p_t2t->p_sec_cmd_buf->offset = NCI_MSG_OFFSET_SIZE + NCI_DATA_HDR_SIZE;
            p = (UINT8 *) (p_t2t->p_sec_cmd_buf + 1) + p_t2t->p_sec_cmd_buf->offset;
            UINT8_TO_BE_STREAM (p, T2T_CMD_WRITE);
            memcpy (p, write_cmd, T2T_WRITE_DATA_LEN + 1);
            p_t2t->p_sec_cmd_buf->len   = 2 + T2T_WRITE_DATA_LEN;
            p_t2t->block_written  = block;

            /* Backup the current substate to move back to this substate after changing sector */
            p_t2t->prev_substate        = p_t2t->substate;
            p_t2t->substate             = RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR_SUPPORT;
            return NFC_STATUS_OK;
        }
        return NFC_STATUS_FAILED;
    }

    /* Send Write command as sector change is not needed */
    if ((status = rw_t2t_send_cmd (T2T_CMD_WRITE, write_cmd)) == NFC_STATUS_OK)
    {
        RW_TRACE_EVENT1 ("rw_t2t_write Sent Command for Block: %u", block);
    }

    return status;
}

/*******************************************************************************
**
** Function         rw_t2t_select
**
** Description      This function selects type 2 tag.
**
** Returns          Tag selection status
**
*******************************************************************************/
tNFC_STATUS rw_t2t_select (void)
{
    tRW_T2T_CB    *p_t2t = &rw_cb.tcb.t2t;

    p_t2t->state       = RW_T2T_STATE_IDLE;
    p_t2t->ndef_status = T2T_NDEF_NOT_DETECTED;


    /* Alloc cmd buf for retransmissions */
    if (p_t2t->p_cur_cmd_buf ==  NULL)
    {
        if ((p_t2t->p_cur_cmd_buf = (BT_HDR *) GKI_getpoolbuf (NFC_RW_POOL_ID)) == NULL)
        {
            RW_TRACE_ERROR0 ("rw_t2t_select: unable to allocate buffer for retransmission");
            return (NFC_STATUS_FAILED);
        }
    }
    /* Alloc cmd buf for holding a command untill sector changes */
    if (p_t2t->p_sec_cmd_buf ==  NULL)
    {
        if ((p_t2t->p_sec_cmd_buf = (BT_HDR *) GKI_getpoolbuf (NFC_RW_POOL_ID)) == NULL)
        {
            RW_TRACE_ERROR0 ("rw_t2t_select: unable to allocate buffer used during sector change");
            return (NFC_STATUS_FAILED);
        }
    }

    NFC_SetStaticRfCback (rw_t2t_conn_cback);
    rw_t2t_handle_op_complete ();
    p_t2t->check_tag_halt = FALSE;

    return NFC_STATUS_OK;
}

/*****************************************************************************
**
** Function         rw_t2t_handle_op_complete
**
** Description      Reset to IDLE state
**
** Returns          Nothing
**
*****************************************************************************/
void rw_t2t_handle_op_complete (void)
{
    tRW_T2T_CB      *p_t2t  = &rw_cb.tcb.t2t;

    if (  (p_t2t->state == RW_T2T_STATE_READ_NDEF)
        ||(p_t2t->state == RW_T2T_STATE_WRITE_NDEF)  )
    {
        p_t2t->b_read_data = FALSE;
    }

    if (p_t2t->state != RW_T2T_STATE_HALT)
        p_t2t->state    = RW_T2T_STATE_IDLE;
    p_t2t->substate = RW_T2T_SUBSTATE_NONE;
    return;
}

/*****************************************************************************
**
** Function         RW_T2tPresenceCheck
**
** Description
**      Check if the tag is still in the field.
**
**      The RW_T2T_PRESENCE_CHECK_EVT w/ status is used to indicate presence
**      or non-presence.
**
** Returns
**      NFC_STATUS_OK, if raw data frame sent
**      NFC_STATUS_NO_BUFFERS: unable to allocate a buffer for this operation
**      NFC_STATUS_FAILED: other error
**
*****************************************************************************/
tNFC_STATUS RW_T2tPresenceCheck (void)
{
    tNFC_STATUS retval = NFC_STATUS_OK;
    tRW_DATA evt_data;
    tRW_CB *p_rw_cb = &rw_cb;
    UINT8 sector_blk = 0;           /* block 0 of current sector */

    RW_TRACE_API0 ("RW_T2tPresenceCheck");

    /* If RW_SelectTagType was not called (no conn_callback) return failure */
    if (!p_rw_cb->p_cback)
    {
        retval = NFC_STATUS_FAILED;
    }
    /* If we are not activated, then RW_T2T_PRESENCE_CHECK_EVT status=FAIL */
    else if (p_rw_cb->tcb.t2t.state == RW_T2T_STATE_NOT_ACTIVATED)
    {
        evt_data.status = NFC_STATUS_FAILED;
        (*p_rw_cb->p_cback) (RW_T2T_PRESENCE_CHECK_EVT, &evt_data);
    }
    /* If command is pending, assume tag is still present */
    else if (p_rw_cb->tcb.t2t.state != RW_T2T_STATE_IDLE)
    {
        evt_data.status = NFC_STATUS_OK;
        (*p_rw_cb->p_cback) (RW_T2T_PRESENCE_CHECK_EVT, &evt_data);
    }
    else
    {
        /* IDLE state: send a READ command to block 0 of the current sector */
        if((retval = rw_t2t_send_cmd (T2T_CMD_READ, &sector_blk))== NFC_STATUS_OK)
        {
            p_rw_cb->tcb.t2t.state = RW_T2T_STATE_CHECK_PRESENCE;
        }
    }

    return (retval);
}

/*******************************************************************************
**
** Function         RW_T2tRead
**
** Description      This function issues the Type 2 Tag READ command. When the
**                  operation is complete the callback function will be called
**                  with a RW_T2T_READ_EVT.
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
tNFC_STATUS RW_T2tRead (UINT16 block)
{
    tRW_T2T_CB  *p_t2t = &rw_cb.tcb.t2t;
    tNFC_STATUS status;

    if (p_t2t->state != RW_T2T_STATE_IDLE)
    {
        RW_TRACE_ERROR1 ("Error: Type 2 tag not activated or Busy - State: %u", p_t2t->state);
        return (NFC_STATUS_FAILED);
    }

    if ((status = rw_t2t_read (block)) == NFC_STATUS_OK)
    {
        p_t2t->state    = RW_T2T_STATE_READ;
        RW_TRACE_EVENT0 ("RW_T2tRead Sent Read command");
    }

    return status;

}

/*******************************************************************************
**
** Function         RW_T2tWrite
**
** Description      This function issues the Type 2 Tag WRITE command. When the
**                  operation is complete the callback function will be called
**                  with a RW_T2T_WRITE_EVT.
**
**                  p_new_bytes points to the array of 4 bytes to be written
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
tNFC_STATUS RW_T2tWrite (UINT16 block, UINT8 *p_write_data)
{
    tRW_T2T_CB  *p_t2t = &rw_cb.tcb.t2t;
    tNFC_STATUS status;

    if (p_t2t->state != RW_T2T_STATE_IDLE)
    {
        RW_TRACE_ERROR1 ("Error: Type 2 tag not activated or Busy - State: %u", p_t2t->state);
        return (NFC_STATUS_FAILED);
    }

    if ((status = rw_t2t_write (block, p_write_data)) == NFC_STATUS_OK)
    {
        p_t2t->state    = RW_T2T_STATE_WRITE;
        if (block < T2T_FIRST_DATA_BLOCK)
            p_t2t->b_read_hdr = FALSE;
        else if (block < (T2T_FIRST_DATA_BLOCK + T2T_READ_BLOCKS))
            p_t2t->b_read_data = FALSE;
        RW_TRACE_EVENT0 ("RW_T2tWrite Sent Write command");
    }

    return status;
}

/*******************************************************************************
**
** Function         RW_T2tSectorSelect
**
** Description      This function issues the Type 2 Tag SECTOR-SELECT command
**                  packet 1. If a NACK is received as the response, the callback
**                  function will be called with a RW_T2T_SECTOR_SELECT_EVT. If
**                  an ACK is received as the response, the command packet 2 with
**                  the given sector number is sent to the peer device. When the
**                  response for packet 2 is received, the callback function will
**                  be called with a RW_T2T_SECTOR_SELECT_EVT.
**
**                  A sector is 256 contiguous blocks (1024 bytes).
**
** Returns          tNFC_STATUS
**
*******************************************************************************/
tNFC_STATUS RW_T2tSectorSelect (UINT8 sector)
{
    tNFC_STATUS status;
    tRW_T2T_CB  *p_t2t       = &rw_cb.tcb.t2t;
    UINT8       sector_byte2[1];

    if (p_t2t->state != RW_T2T_STATE_IDLE)
    {
        RW_TRACE_ERROR1 ("Error: Type 2 tag not activated or Busy - State: %u", p_t2t->state);
        return (NFC_STATUS_FAILED);
    }

    if (sector >= T2T_MAX_SECTOR)
    {
        RW_TRACE_ERROR2 ("RW_T2tSectorSelect - Invalid sector: %u, T2 Max supported sector value: %u", sector, T2T_MAX_SECTOR - 1);
        return (NFC_STATUS_FAILED);
    }

    sector_byte2[0] = 0xFF;

    if ((status = rw_t2t_send_cmd (T2T_CMD_SEC_SEL, sector_byte2)) == NFC_STATUS_OK)
    {
        p_t2t->state         = RW_T2T_STATE_SELECT_SECTOR;
        p_t2t->select_sector = sector;
        p_t2t->substate      = RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR_SUPPORT;

        RW_TRACE_EVENT0 ("RW_T2tSectorSelect Sent Sector select first command");
    }

    return status;
}

#if (BT_TRACE_VERBOSE == TRUE)
/*******************************************************************************
**
** Function         rw_t2t_get_state_name
**
** Description      This function returns the state name.
**
** NOTE             conditionally compiled to save memory.
**
** Returns          pointer to the name
**
*******************************************************************************/
static char *rw_t2t_get_state_name (UINT8 state)
{
    switch (state)
    {
    case RW_T2T_STATE_NOT_ACTIVATED:
        return ("NOT_ACTIVATED");
    case RW_T2T_STATE_IDLE:
        return ("IDLE");
    case RW_T2T_STATE_READ:
        return ("APP_READ");
    case RW_T2T_STATE_WRITE:
        return ("APP_WRITE");
    case RW_T2T_STATE_SELECT_SECTOR:
        return ("SECTOR_SELECT");
    case RW_T2T_STATE_DETECT_TLV:
        return ("TLV_DETECT");
    case RW_T2T_STATE_READ_NDEF:
        return ("READ_NDEF");
    case RW_T2T_STATE_WRITE_NDEF:
        return ("WRITE_NDEF");
    case RW_T2T_STATE_SET_TAG_RO:
        return ("SET_TAG_RO");
    case RW_T2T_STATE_CHECK_PRESENCE:
        return ("CHECK_PRESENCE");
    default:
        return ("???? UNKNOWN STATE");
    }
}

/*******************************************************************************
**
** Function         rw_t2t_get_substate_name
**
** Description      This function returns the substate name.
**
** NOTE             conditionally compiled to save memory.
**
** Returns          pointer to the name
**
*******************************************************************************/
static char *rw_t2t_get_substate_name (UINT8 substate)
{
    switch (substate)
    {
    case RW_T2T_SUBSTATE_NONE:
        return ("RW_T2T_SUBSTATE_NONE");
    case RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR_SUPPORT:
        return ("RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR_SUPPORT");
    case RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR:
        return ("RW_T2T_SUBSTATE_WAIT_SELECT_SECTOR");
    case RW_T2T_SUBSTATE_WAIT_READ_CC:
        return ("RW_T2T_SUBSTATE_WAIT_READ_CC");
    case RW_T2T_SUBSTATE_WAIT_TLV_DETECT:
        return ("RW_T2T_SUBSTATE_WAIT_TLV_DETECT");
    case RW_T2T_SUBSTATE_WAIT_FIND_LEN_FIELD_LEN:
        return ("RW_T2T_SUBSTATE_WAIT_FIND_LEN_FIELD_LEN");
    case RW_T2T_SUBSTATE_WAIT_READ_TLV_LEN0:
        return ("RW_T2T_SUBSTATE_WAIT_READ_TLV_LEN0");
    case RW_T2T_SUBSTATE_WAIT_READ_TLV_LEN1:
        return ("RW_T2T_SUBSTATE_WAIT_READ_TLV_LEN1");
    case RW_T2T_SUBSTATE_WAIT_READ_TLV_VALUE:
        return ("RW_T2T_SUBSTATE_WAIT_READ_TLV_VALUE");
    case RW_T2T_SUBSTATE_WAIT_READ_LOCKS:
        return ("RW_T2T_SUBSTATE_WAIT_READ_LOCKS");
    case RW_T2T_SUBSTATE_WAIT_READ_NDEF_FIRST_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_READ_NDEF_FIRST_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_READ_NDEF_LAST_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_READ_NDEF_LAST_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_READ_TERM_TLV_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_READ_TERM_TLV_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_READ_NDEF_NEXT_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_READ_NDEF_NEXT_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_NEXT_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_NEXT_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_LAST_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_LAST_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_READ_NDEF_LEN_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_READ_NDEF_LEN_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_LEN_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_LEN_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_LEN_NEXT_BLOCK:
        return ("RW_T2T_SUBSTATE_WAIT_WRITE_NDEF_LEN_NEXT_BLOCK");
    case RW_T2T_SUBSTATE_WAIT_WRITE_TERM_TLV_CMPLT:
        return ("RW_T2T_SUBSTATE_WAIT_WRITE_TERM_TLV_CMPLT");
    default:
        return ("???? UNKNOWN SUBSTATE");
    }
}

#endif /* (BT_TRACE_VERBOSE == TRUE) */

#endif /* NFC_INCLUDED == TRUE*/