stack/mcap/mca_dsm.cc

/******************************************************************************
 *
 *  Copyright 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 Data chahnel state machine.
 *
 ******************************************************************************/
#include <string.h>

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

/*****************************************************************************
 * data channel state machine constants and types
 ****************************************************************************/
enum {
  MCA_DCB_TC_OPEN,
  MCA_DCB_CONG,
  MCA_DCB_FREE_DATA,
  MCA_DCB_DEALLOC,
  MCA_DCB_DO_DISCONN,
  MCA_DCB_SND_DATA,
  MCA_DCB_HDL_DATA,
  MCA_DCB_NUM_ACTIONS
};
#define MCA_DCB_IGNORE MCA_DCB_NUM_ACTIONS

/* action function list */
const tMCA_DCB_ACTION mca_dcb_action[] = {
    mca_dcb_tc_open,    mca_dcb_cong,     mca_dcb_free_data, mca_dcb_dealloc,
    mca_dcb_do_disconn, mca_dcb_snd_data, mca_dcb_hdl_data};

/* state table information */
#define MCA_DCB_ACTIONS 1    /* number of actions */
#define MCA_DCB_ACT_COL 0    /* position of action function */
#define MCA_DCB_NEXT_STATE 1 /* position of next state */
#define MCA_DCB_NUM_COLS 2   /* number of columns in state tables */

/* state table for opening state */
const uint8_t mca_dcb_st_opening[][MCA_DCB_NUM_COLS] = {
    /* Event                            Action              Next State */
    /* MCA_DCB_API_CLOSE_EVT    */ {MCA_DCB_DO_DISCONN, MCA_DCB_CLOSING_ST},
    /* MCA_DCB_API_WRITE_EVT    */ {MCA_DCB_IGNORE, MCA_DCB_OPENING_ST},
    /* MCA_DCB_TC_OPEN_EVT      */ {MCA_DCB_TC_OPEN, MCA_DCB_OPEN_ST},
    /* MCA_DCB_TC_CLOSE_EVT     */ {MCA_DCB_DEALLOC, MCA_DCB_NULL_ST},
    /* MCA_DCB_TC_CONG_EVT      */ {MCA_DCB_CONG, MCA_DCB_OPENING_ST},
    /* MCA_DCB_TC_DATA_EVT      */ {MCA_DCB_FREE_DATA, MCA_DCB_OPENING_ST}};

/* state table for open state */
const uint8_t mca_dcb_st_open[][MCA_DCB_NUM_COLS] = {
    /* Event                            Action              Next State */
    /* MCA_DCB_API_CLOSE_EVT    */ {MCA_DCB_DO_DISCONN, MCA_DCB_CLOSING_ST},
    /* MCA_DCB_API_WRITE_EVT    */ {MCA_DCB_SND_DATA, MCA_DCB_OPEN_ST},
    /* MCA_DCB_TC_OPEN_EVT      */ {MCA_DCB_IGNORE, MCA_DCB_OPEN_ST},
    /* MCA_DCB_TC_CLOSE_EVT     */ {MCA_DCB_DEALLOC, MCA_DCB_NULL_ST},
    /* MCA_DCB_TC_CONG_EVT      */ {MCA_DCB_CONG, MCA_DCB_OPEN_ST},
    /* MCA_DCB_TC_DATA_EVT      */ {MCA_DCB_HDL_DATA, MCA_DCB_OPEN_ST}};

/* state table for closing state */
const uint8_t mca_dcb_st_closing[][MCA_DCB_NUM_COLS] = {
    /* Event                            Action              Next State */
    /* MCA_DCB_API_CLOSE_EVT    */ {MCA_DCB_IGNORE, MCA_DCB_CLOSING_ST},
    /* MCA_DCB_API_WRITE_EVT    */ {MCA_DCB_IGNORE, MCA_DCB_CLOSING_ST},
    /* MCA_DCB_TC_OPEN_EVT      */ {MCA_DCB_TC_OPEN, MCA_DCB_OPEN_ST},
    /* MCA_DCB_TC_CLOSE_EVT     */ {MCA_DCB_DEALLOC, MCA_DCB_NULL_ST},
    /* MCA_DCB_TC_CONG_EVT      */ {MCA_DCB_IGNORE, MCA_DCB_CLOSING_ST},
    /* MCA_DCB_TC_DATA_EVT      */ {MCA_DCB_FREE_DATA, MCA_DCB_CLOSING_ST}};

/* type for state table */
typedef const uint8_t (*tMCA_DCB_ST_TBL)[MCA_DCB_NUM_COLS];

/* state table */
const tMCA_DCB_ST_TBL mca_dcb_st_tbl[] = {mca_dcb_st_opening, mca_dcb_st_open,
                                          mca_dcb_st_closing};

/* verbose event strings for trace */
const char* const mca_dcb_evt_str[] = {"API_CLOSE_EVT", "API_WRITE_EVT",
                                       "TC_OPEN_EVT",   "TC_CLOSE_EVT",
                                       "TC_CONG_EVT",   "TC_DATA_EVT"};
/* verbose state strings for trace */
const char* const mca_dcb_st_str[] = {"NULL_ST", "OPENING_ST", "OPEN_ST",
                                      "CLOSING_ST"};

/*******************************************************************************
 *
 * Function         mca_dcb_event
 *
 * Description      This function is the DCB state machine main function.
 *                  It uses the state and action function tables to execute
 *                  action functions.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_dcb_event(tMCA_DCB* p_dcb, uint8_t event, tMCA_DCB_EVT* p_data) {
  tMCA_DCB_ST_TBL state_table;
  uint8_t action;

  if (p_dcb == NULL) return;
  MCA_TRACE_EVENT("DCB dcb=%d event=%s state=%s", mca_dcb_to_hdl(p_dcb),
                  mca_dcb_evt_str[event], mca_dcb_st_str[p_dcb->state]);

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

  /* set next state */
  p_dcb->state = state_table[event][MCA_DCB_NEXT_STATE];

  /* execute action functions */
  action = state_table[event][MCA_DCB_ACT_COL];
  if (action != MCA_DCB_IGNORE) {
    (*mca_dcb_action[action])(p_dcb, p_data);
  }
}

/*******************************************************************************
 *
 * Function         mca_dcb_alloc
 *
 * Description      This function is called to allocate an DCB.
 *                  It initializes the DCB with the data passed to the function.
 *
 * Returns          tMCA_DCB *
 *
 ******************************************************************************/
tMCA_DCB* mca_dcb_alloc(tMCA_CCB* p_ccb, tMCA_DEP dep) {
  tMCA_DCB *p_dcb = NULL, *p_dcb_tmp;
  tMCA_RCB* p_rcb = p_ccb->p_rcb;
  tMCA_CS* p_cs;
  int i, max;

  if (dep < MCA_NUM_DEPS) {
    p_cs = &p_rcb->dep[dep];
    i = mca_ccb_to_hdl(p_ccb) - 1;
    p_dcb_tmp = &mca_cb.dcb[i * MCA_NUM_MDLS];
    /* make sure p_cs->max_mdl is smaller than MCA_NUM_MDLS at MCA_CreateDep */
    max = p_cs->max_mdl;
    for (i = 0; i < max; i++, p_dcb_tmp++) {
      if (p_dcb_tmp->state == MCA_DCB_NULL_ST) {
        p_dcb_tmp->p_ccb = p_ccb;
        p_dcb_tmp->state = MCA_DCB_OPENING_ST;
        p_dcb_tmp->cong = true;
        p_dcb_tmp->p_cs = p_cs;
        p_dcb = p_dcb_tmp;
        break;
      }
    }
  }
  return p_dcb;
}

/*******************************************************************************
 *
 * Function         mca_dep_free_mdl
 *
 * Description      This function is called to check the number of free mdl for
 *                  the given dep.
 *
 * Returns          the number of free mdl for the given dep
 *
 ******************************************************************************/
uint8_t mca_dep_free_mdl(tMCA_CCB* p_ccb, tMCA_DEP dep) {
  tMCA_DCB* p_dcb;
  tMCA_RCB* p_rcb = p_ccb->p_rcb;
  tMCA_CS* p_cs;
  int i, max;
  uint8_t count = 0;
  uint8_t left;

  if (dep < MCA_NUM_DEPS) {
    p_cs = &p_rcb->dep[dep];
    i = mca_ccb_to_hdl(p_ccb) - 1;
    p_dcb = &mca_cb.dcb[i * MCA_NUM_MDLS];
    /* make sure p_cs->max_mdl is smaller than MCA_NUM_MDLS at MCA_CreateDep */
    max = p_cs->max_mdl;
    for (i = 0; i < max; i++, p_dcb++) {
      if ((p_dcb->state != MCA_DCB_NULL_ST) && (p_dcb->p_cs == p_cs)) {
        count++;
        break;
      }
    }
  } else {
    max = 0;
    MCA_TRACE_WARNING("Invalid Dep ID");
  }
  left = max - count;
  return left;
}

/*******************************************************************************
 *
 * Function         mca_dcb_dealloc
 *
 * Description      This function deallocates an DCB.
 *
 * Returns          void.
 *
 ******************************************************************************/
void mca_dcb_dealloc(tMCA_DCB* p_dcb, tMCA_DCB_EVT* p_data) {
  tMCA_CCB* p_ccb = p_dcb->p_ccb;
  uint8_t event = MCA_CLOSE_IND_EVT;
  tMCA_CTRL evt_data;

  MCA_TRACE_DEBUG("mca_dcb_dealloc");
  osi_free_and_reset((void**)&p_dcb->p_data);
  if (p_data) {
    /* non-NULL -> an action function -> report disconnect event */
    evt_data.close_cfm.mdl = mca_dcb_to_hdl(p_dcb);
    evt_data.close_cfm.reason = p_data->close.reason;
    evt_data.close_cfm.mdl_id = p_dcb->mdl_id;
    if (p_data->close.param == MCA_INT) event = MCA_CLOSE_CFM_EVT;
    if (p_data->close.lcid) mca_ccb_report_event(p_ccb, event, &evt_data);
  }
  mca_free_tc_tbl_by_lcid(p_dcb->lcid);
  memset(p_dcb, 0, sizeof(tMCA_DCB));
}

/*******************************************************************************
 *
 * Function         mca_dcb_to_hdl
 *
 * Description      Convert a pointer to a DCB to a handle (tMCA_DL).
 *                  It returns the handle.
 *
 * Returns          tMCA_DL.
 *
 ******************************************************************************/
tMCA_DL mca_dcb_to_hdl(tMCA_DCB* p_dcb) {
  return (uint8_t)(p_dcb - mca_cb.dcb + 1);
}

/*******************************************************************************
 *
 * Function         mca_dcb_by_hdl
 *
 * Description      This function finds the DCB for a handle (tMCA_DL).
 *                  It returns a pointer to the DCB.
 *                  If no DCB matches the handle it returns NULL.
 *
 * Returns          tMCA_DCB *
 *
 ******************************************************************************/
tMCA_DCB* mca_dcb_by_hdl(tMCA_DL hdl) {
  tMCA_DCB* p_dcb = NULL;
  if (hdl && hdl <= MCA_NUM_DCBS && mca_cb.dcb[hdl - 1].state)
    p_dcb = &mca_cb.dcb[hdl - 1];
  return p_dcb;
}

/*******************************************************************************
 *
 * Function         mca_dcb_close_by_mdl_id
 *
 * Description      This function finds the DCB for a mdl_id and
 *                  disconnect the mdl
 *
 * Returns          void
 *
 ******************************************************************************/
void mca_dcb_close_by_mdl_id(tMCA_CCB* p_ccb, uint16_t mdl_id) {
  tMCA_DCB* p_dcb;
  int i;

  MCA_TRACE_DEBUG("mca_dcb_close_by_mdl_id mdl_id=%d", mdl_id);
  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) {
      if (p_dcb->mdl_id == mdl_id) {
        mca_dcb_event(p_dcb, MCA_DCB_API_CLOSE_EVT, NULL);
        break;
      } else if (mdl_id == MCA_ALL_MDL_ID) {
        mca_dcb_event(p_dcb, MCA_DCB_API_CLOSE_EVT, NULL);
      }
    }
  }
}