PL286/system/bt/stack/mcap/mca_csm.cc

/******************************************************************************
 *
 *  Copyright (C) 2009-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  This is the implementation file for the MCAP Control channel state
 *  machine.
 *
 ******************************************************************************/
#include <string.h>

#include "bt_target.h"
#include "btu.h"
#include "mca_api.h"
#include "mca_defs.h"
#include "mca_int.h"

/*****************************************************************************
 * data channel state machine constants and types
 ****************************************************************************/
enum {
  MCA_CCB_FREE_MSG,
  MCA_CCB_SND_REQ,
  MCA_CCB_SND_RSP,
  MCA_CCB_DO_DISCONN,
  MCA_CCB_CONG,
  MCA_CCB_HDL_REQ,
  MCA_CCB_HDL_RSP,
  MCA_CCB_LL_OPEN,
  MCA_CCB_DL_OPEN,
  MCA_CCB_DEALLOC,
  MCA_CCB_RSP_TOUT,
  MCA_CCB_NUM_ACTIONS
};
#define MCA_CCB_IGNORE MCA_CCB_NUM_ACTIONS

/* action function list */
const tMCA_CCB_ACTION mca_ccb_action[] = {
    mca_ccb_free_msg, mca_ccb_snd_req, mca_ccb_snd_rsp,  mca_ccb_do_disconn,
    mca_ccb_cong,     mca_ccb_hdl_req, mca_ccb_hdl_rsp,  mca_ccb_ll_open,
    mca_ccb_dl_open,  mca_ccb_dealloc, mca_ccb_rsp_tout,
};

/* state table information */
#define MCA_CCB_ACTIONS 1    /* number of actions */
#define MCA_CCB_ACT_COL 0    /* position of action function */
#define MCA_CCB_NEXT_STATE 1 /* position of next state */
#define MCA_CCB_NUM_COLS 2   /* number of columns in state tables */

/* state table for opening state */
const uint8_t mca_ccb_st_opening[][MCA_CCB_NUM_COLS] = {
    /* Event                            Action              Next State */
    /* MCA_CCB_API_CONNECT_EVT    */ {MCA_CCB_IGNORE, MCA_CCB_OPENING_ST},
    /* MCA_CCB_API_DISCONNECT_EVT */ {MCA_CCB_DO_DISCONN, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_API_REQ_EVT        */ {MCA_CCB_FREE_MSG, MCA_CCB_OPENING_ST},
    /* MCA_CCB_API_RSP_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_OPENING_ST},
    /* MCA_CCB_MSG_REQ_EVT        */ {MCA_CCB_FREE_MSG, MCA_CCB_OPENING_ST},
    /* MCA_CCB_MSG_RSP_EVT        */ {MCA_CCB_FREE_MSG, MCA_CCB_OPENING_ST},
    /* MCA_CCB_DL_OPEN_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_OPENING_ST},
    /* MCA_CCB_LL_OPEN_EVT        */ {MCA_CCB_LL_OPEN, MCA_CCB_OPEN_ST},
    /* MCA_CCB_LL_CLOSE_EVT       */ {MCA_CCB_DEALLOC, MCA_CCB_NULL_ST},
    /* MCA_CCB_LL_CONG_EVT        */ {MCA_CCB_CONG, MCA_CCB_OPENING_ST},
    /* MCA_CCB_RSP_TOUT_EVT       */ {MCA_CCB_IGNORE, MCA_CCB_OPENING_ST}};

/* state table for open state */
const uint8_t mca_ccb_st_open[][MCA_CCB_NUM_COLS] = {
    /* Event                            Action              Next State */
    /* MCA_CCB_API_CONNECT_EVT    */ {MCA_CCB_IGNORE, MCA_CCB_OPEN_ST},
    /* MCA_CCB_API_DISCONNECT_EVT */ {MCA_CCB_DO_DISCONN, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_API_REQ_EVT        */ {MCA_CCB_SND_REQ, MCA_CCB_OPEN_ST},
    /* MCA_CCB_API_RSP_EVT        */ {MCA_CCB_SND_RSP, MCA_CCB_OPEN_ST},
    /* MCA_CCB_MSG_REQ_EVT        */ {MCA_CCB_HDL_REQ, MCA_CCB_OPEN_ST},
    /* MCA_CCB_MSG_RSP_EVT        */ {MCA_CCB_HDL_RSP, MCA_CCB_OPEN_ST},
    /* MCA_CCB_DL_OPEN_EVT        */ {MCA_CCB_DL_OPEN, MCA_CCB_OPEN_ST},
    /* MCA_CCB_LL_OPEN_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_OPEN_ST},
    /* MCA_CCB_LL_CLOSE_EVT       */ {MCA_CCB_DEALLOC, MCA_CCB_NULL_ST},
    /* MCA_CCB_LL_CONG_EVT        */ {MCA_CCB_CONG, MCA_CCB_OPEN_ST},
    /* MCA_CCB_RSP_TOUT_EVT       */ {MCA_CCB_RSP_TOUT, MCA_CCB_OPEN_ST}};

/* state table for closing state */
const uint8_t mca_ccb_st_closing[][MCA_CCB_NUM_COLS] = {
    /* Event                            Action              Next State */
    /* MCA_CCB_API_CONNECT_EVT    */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_API_DISCONNECT_EVT */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_API_REQ_EVT        */ {MCA_CCB_FREE_MSG, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_API_RSP_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_MSG_REQ_EVT        */ {MCA_CCB_FREE_MSG, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_MSG_RSP_EVT        */ {MCA_CCB_FREE_MSG, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_DL_OPEN_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_LL_OPEN_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_LL_CLOSE_EVT       */ {MCA_CCB_DEALLOC, MCA_CCB_NULL_ST},
    /* MCA_CCB_LL_CONG_EVT        */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST},
    /* MCA_CCB_RSP_TOUT_EVT       */ {MCA_CCB_IGNORE, MCA_CCB_CLOSING_ST}};

/* type for state table */
typedef const uint8_t (*tMCA_CCB_ST_TBL)[MCA_CCB_NUM_COLS];

/* state table */
const tMCA_CCB_ST_TBL mca_ccb_st_tbl[] = {mca_ccb_st_opening, mca_ccb_st_open,
                                          mca_ccb_st_closing};

/* verbose event strings for trace */
static const char* const mca_ccb_evt_str[] = {
    "API_CONNECT_EVT", "API_DISCONNECT_EVT", "API_REQ_EVT", "API_RSP_EVT",
    "MSG_REQ_EVT",     "MSG_RSP_EVT",        "DL_OPEN_EVT", "LL_OPEN_EVT",
    "LL_CLOSE_EVT",    "LL_CONG_EVT",        "RSP_TOUT_EVT"};
/* verbose state strings for trace */
static const char* const mca_ccb_st_str[] = {"NULL_ST", "OPENING_ST", "OPEN_ST",
                                             "CLOSING_ST"};

/*******************************************************************************
 *
 * Function         mca_stop_timer
 *
 * Description      This function is stop a MCAP timer
 *
 *                  This function is for use internal to MCAP only.
 *
 * Returns          void
 *
 ******************************************************************************/
void mca_stop_timer(tMCA_CCB* p_ccb) { alarm_cancel(p_ccb->mca_ccb_timer); }

/*******************************************************************************
 *
 * Function         mca_ccb_event
 *
 * Description      This function is the CCB state machine main function.
 *                  It uses the state and action function tables to execute
 *                  action functions.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_event(tMCA_CCB* p_ccb, uint8_t event, tMCA_CCB_EVT* p_data) {
  tMCA_CCB_ST_TBL state_table;
  uint8_t action;

  MCA_TRACE_EVENT("CCB ccb=%d event=%s state=%s", mca_ccb_to_hdl(p_ccb),
                  mca_ccb_evt_str[event], mca_ccb_st_str[p_ccb->state]);

  /* look up the state table for the current state */
  state_table = mca_ccb_st_tbl[p_ccb->state - 1];

  /* set next state */
  p_ccb->state = state_table[event][MCA_CCB_NEXT_STATE];

  /* execute action functions */
  action = state_table[event][MCA_CCB_ACT_COL];
  if (action != MCA_CCB_IGNORE) {
    (*mca_ccb_action[action])(p_ccb, p_data);
  }
}

/*******************************************************************************
 *
 * Function         mca_ccb_by_bd
 *
 * Description      This function looks up the CCB based on the BD address.
 *                  It returns a pointer to the CCB.
 *                  If no CCB is found it returns NULL.
 *
 * Returns          void.
 *
 ******************************************************************************/
tMCA_CCB* mca_ccb_by_bd(tMCA_HANDLE handle, const RawAddress& bd_addr) {
  tMCA_CCB* p_ccb = NULL;
  tMCA_RCB* p_rcb = mca_rcb_by_handle(handle);
  tMCA_CCB* p_ccb_tmp;
  int i;

  if (p_rcb) {
    i = handle - 1;
    p_ccb_tmp = &mca_cb.ccb[i * MCA_NUM_LINKS];
    for (i = 0; i < MCA_NUM_LINKS; i++, p_ccb_tmp++) {
      if (p_ccb_tmp->state != MCA_CCB_NULL_ST &&
          p_ccb_tmp->peer_addr == bd_addr) {
        p_ccb = p_ccb_tmp;
        break;
      }
    }
  }
  return p_ccb;
}

/*******************************************************************************
 *
 * Function         mca_ccb_alloc
 *
 * Description      This function allocates a CCB and copies the BD address to
 *                  the CCB.  It returns a pointer to the CCB.  If no CCB can
 *                  be allocated it returns NULL.
 *
 * Returns          void.
 *
 ******************************************************************************/
tMCA_CCB* mca_ccb_alloc(tMCA_HANDLE handle, const RawAddress& bd_addr) {
  tMCA_CCB* p_ccb = NULL;
  tMCA_RCB* p_rcb = mca_rcb_by_handle(handle);
  tMCA_CCB* p_ccb_tmp;
  int i;

  MCA_TRACE_DEBUG("mca_ccb_alloc handle:0x%x", handle);
  if (p_rcb) {
    i = handle - 1;
    p_ccb_tmp = &mca_cb.ccb[i * MCA_NUM_LINKS];
    for (i = 0; i < MCA_NUM_LINKS; i++, p_ccb_tmp++) {
      if (p_ccb_tmp->state == MCA_CCB_NULL_ST) {
        p_ccb_tmp->p_rcb = p_rcb;
        p_ccb_tmp->mca_ccb_timer = alarm_new("mca.mca_ccb_timer");
        p_ccb_tmp->state = MCA_CCB_OPENING_ST;
        p_ccb_tmp->cong = true;
        p_ccb_tmp->peer_addr = bd_addr;
        p_ccb = p_ccb_tmp;
        break;
      }
    }
  }
  return p_ccb;
}

/*******************************************************************************
 *
 * Function         mca_ccb_dealloc
 *
 * Description      This function deallocates a CCB.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_ccb_dealloc(tMCA_CCB* p_ccb, tMCA_CCB_EVT* p_data) {
  tMCA_CTRL evt_data;

  MCA_TRACE_DEBUG("mca_ccb_dealloc ctrl_vpsm:0x%x", p_ccb->ctrl_vpsm);
  mca_dcb_close_by_mdl_id(p_ccb, MCA_ALL_MDL_ID);
  if (p_ccb->ctrl_vpsm) {
    L2CA_Deregister(p_ccb->ctrl_vpsm);
  }
  if (p_ccb->data_vpsm) {
    L2CA_Deregister(p_ccb->data_vpsm);
  }
  osi_free_and_reset((void**)&p_ccb->p_rx_msg);
  osi_free_and_reset((void**)&p_ccb->p_tx_req);
  mca_stop_timer(p_ccb);

  if (p_data) {
    /* non-NULL -> an action function -> report disconnect event */
    evt_data.disconnect_ind.bd_addr = p_ccb->peer_addr;
    evt_data.disconnect_ind.reason = p_data->close.reason;
    mca_ccb_report_event(p_ccb, MCA_DISCONNECT_IND_EVT, &evt_data);
  }
  mca_free_tc_tbl_by_lcid(p_ccb->lcid);
  alarm_free(p_ccb->mca_ccb_timer);
  memset(p_ccb, 0, sizeof(tMCA_CCB));
}

/*******************************************************************************
 *
 * Function         mca_ccb_to_hdl
 *
 * Description      This function converts a pointer to a CCB to a tMCA_CL
 *                  and returns the value.
 *
 * Returns          void.
 *
 ******************************************************************************/
tMCA_CL mca_ccb_to_hdl(tMCA_CCB* p_ccb) {
  return (uint8_t)(p_ccb - mca_cb.ccb + 1);
}

/*******************************************************************************
 *
 * Function         mca_ccb_by_hdl
 *
 * Description      This function converts an index value to a CCB.  It returns
 *                  a pointer to the CCB.  If no valid CCB matches the index it
 *                  returns NULL.
 *
 * Returns          void.
 *
 ******************************************************************************/
tMCA_CCB* mca_ccb_by_hdl(tMCA_CL mcl) {
  tMCA_CCB* p_ccb = NULL;
  if (mcl && mcl <= MCA_NUM_CCBS && mca_cb.ccb[mcl - 1].state)
    p_ccb = &mca_cb.ccb[mcl - 1];
  return p_ccb;
}

/*******************************************************************************
 *
 * Function         mca_ccb_uses_mdl_id
 *
 * Description      This function checkes if a given mdl_id is in use.
 *
 * Returns          true, if the given mdl_id is currently used in the MCL.
 *
 ******************************************************************************/
bool mca_ccb_uses_mdl_id(tMCA_CCB* p_ccb, uint16_t mdl_id) {
  bool uses = false;
  tMCA_DCB* p_dcb;
  int i;

  i = mca_ccb_to_hdl(p_ccb) - 1;
  p_dcb = &mca_cb.dcb[i * MCA_NUM_MDLS];
  for (i = 0; i < MCA_NUM_MDLS; i++, p_dcb++) {
    if (p_dcb->state != MCA_DCB_NULL_ST && p_dcb->mdl_id == mdl_id) {
      uses = true;
      break;
    }
  }

  return uses;
}