stack/avdt/avdt_ccb_act.c

/******************************************************************************
 *
 *  Copyright (C) 2006-2012 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 module contains the action functions associated with the channel
 *  control block state machine.
 *
 ******************************************************************************/

#include <string.h>
#include "data_types.h"
#include "bt_target.h"
#include "avdt_api.h"
#include "avdtc_api.h"
#include "avdt_int.h"
#include "gki.h"
#include "btu.h"
#include "btm_api.h"

/*******************************************************************************
**
** Function         avdt_ccb_clear_ccb
**
** Description      This function clears out certain buffers, queues, and
**                  other data elements of a ccb.
**
**
** Returns          void.
**
*******************************************************************************/
static void avdt_ccb_clear_ccb(tAVDT_CCB *p_ccb)
{
    BT_HDR          *p_buf;

    /* clear certain ccb variables */
    p_ccb->cong = FALSE;
    p_ccb->ret_count = 0;

    /* free message being fragmented */
    if (p_ccb->p_curr_msg != NULL)
    {
        GKI_freebuf(p_ccb->p_curr_msg);
        p_ccb->p_curr_msg = NULL;
    }

    /* free message being reassembled */
    if (p_ccb->p_rx_msg != NULL)
    {
        GKI_freebuf(p_ccb->p_rx_msg);
        p_ccb->p_rx_msg = NULL;
    }

    /* clear out response queue */
    while ((p_buf = (BT_HDR *) GKI_dequeue(&p_ccb->rsp_q)) != NULL)
    {
        GKI_freebuf(p_buf);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_chan_open
**
** Description      This function calls avdt_ad_open_req() to
**                  initiate a signaling channel connection.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_chan_open(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    BTM_SetOutService(p_ccb->peer_addr, BTM_SEC_SERVICE_AVDTP, AVDT_CHAN_SIG);
    avdt_ad_open_req(AVDT_CHAN_SIG, p_ccb, NULL, AVDT_INT);
}

/*******************************************************************************
**
** Function         avdt_ccb_chan_close
**
** Description      This function calls avdt_ad_close_req() to close a
**                  signaling channel connection.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_chan_close(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* close the transport channel used by this CCB */
    avdt_ad_close_req(AVDT_CHAN_SIG, p_ccb, NULL);
}

/*******************************************************************************
**
** Function         avdt_ccb_chk_close
**
** Description      This function checks for active streams on this CCB.
**                  If there are none, it starts an idle timer.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_chk_close(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    int         i;
    tAVDT_SCB   *p_scb = &avdt_cb.scb[0];

    /* see if there are any active scbs associated with this ccb */
    for (i = 0; i < AVDT_NUM_SEPS; i++, p_scb++)
    {
        if ((p_scb->allocated) && (p_scb->p_ccb == p_ccb))
        {
            break;
        }
    }

    /* if no active scbs start idle timer */
    if (i == AVDT_NUM_SEPS)
    {
        btu_start_timer(&p_ccb->timer_entry, BTU_TTYPE_AVDT_CCB_IDLE, avdt_cb.rcb.idle_tout);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_discover_cmd
**
** Description      This function is called when a discover command is
**                  received from the peer.  It gathers up the stream
**                  information for all allocated streams and initiates
**                  sending of a discover response.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_discover_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_SEP_INFO      sep_info[AVDT_NUM_SEPS];
    tAVDT_SCB           *p_scb = &avdt_cb.scb[0];
    int                 i;

    p_data->msg.discover_rsp.p_sep_info = sep_info;
    p_data->msg.discover_rsp.num_seps = 0;

    /* for all allocated scbs */
    for (i = 0; i < AVDT_NUM_SEPS; i++, p_scb++)
    {
        if (p_scb->allocated)
        {
            /* copy sep info */
            sep_info[i].in_use = p_scb->in_use;
            sep_info[i].seid = i + 1;
            sep_info[i].media_type = p_scb->cs.media_type;
            sep_info[i].tsep = p_scb->cs.tsep;

            p_data->msg.discover_rsp.num_seps++;
        }
    }

    /* send response */
    avdt_ccb_event(p_ccb, AVDT_CCB_API_DISCOVER_RSP_EVT, p_data);
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_discover_rsp
**
** Description      This function is called when a discover response or
**                  reject is received from the peer.  It calls the application
**                  callback function with the results.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_discover_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* we're done with procedure */
    p_ccb->proc_busy = FALSE;

    /* call app callback with results */
    (*p_ccb->proc_cback)(0, p_ccb->peer_addr, AVDT_DISCOVER_CFM_EVT,
                         (tAVDT_CTRL *)(&p_data->msg.discover_rsp));
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_getcap_cmd
**
** Description      This function is called when a get capabilities command
**                  is received from the peer.  It retrieves the stream
**                  configuration for the requested stream and initiates
**                  sending of a get capabilities response.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_getcap_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_SCB       *p_scb;

    /* look up scb for seid sent to us */
    p_scb = avdt_scb_by_hdl(p_data->msg.single.seid);

    p_data->msg.svccap.p_cfg = &p_scb->cs.cfg;

    avdt_ccb_event(p_ccb, AVDT_CCB_API_GETCAP_RSP_EVT, p_data);
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_getcap_rsp
**
** Description      This function is called with a get capabilities response
**                  or reject is received from the peer.  It calls the
**                  application callback function with the results.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_getcap_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* we're done with procedure */
    p_ccb->proc_busy = FALSE;

    /* call app callback with results */
    (*p_ccb->proc_cback)(0, p_ccb->peer_addr, AVDT_GETCAP_CFM_EVT,
                         (tAVDT_CTRL *)(&p_data->msg.svccap));
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_start_cmd
**
** Description      This function is called when a start command is received
**                  from the peer.  It verifies that all requested streams
**                  are in the proper state.  If so, it initiates sending of
**                  a start response.  Otherwise it sends a start reject.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_start_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8   seid;
    UINT8   err_code;

    /* verify all streams in the right state */
    if ((seid = avdt_scb_verify(p_ccb, AVDT_VERIFY_START, p_data->msg.multi.seid_list,
                                p_data->msg.multi.num_seps, &err_code)) == 0)
    {
        /* we're ok, send response */
        avdt_ccb_event(p_ccb, AVDT_CCB_API_START_RSP_EVT, p_data);
    }
    else
    {
        /* not ok, send reject */
        p_data->msg.hdr.err_code = err_code;
        p_data->msg.hdr.err_param = seid;
        avdt_msg_send_rej(p_ccb, AVDT_SIG_START, &p_data->msg);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_start_rsp
**
** Description      This function is called when a start response or reject
**                  is received from the peer.  Using the SEIDs stored in the
**                  current command message, it sends a start response or start
**                  reject event to each SCB associated with the command.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_start_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8       event;
    int         i;
    UINT8       *p;
    tAVDT_SCB   *p_scb;

    /* determine rsp or rej event */
    event = (p_data->msg.hdr.err_code == 0) ?
            AVDT_SCB_MSG_START_RSP_EVT : AVDT_SCB_MSG_START_REJ_EVT;

    /* get to where seid's are stashed in current cmd */
    p = (UINT8 *)(p_ccb->p_curr_cmd + 1);

    /* little trick here; length of current command equals number of streams */
    for (i = 0; i < p_ccb->p_curr_cmd->len; i++)
    {
        if ((p_scb = avdt_scb_by_hdl(p[i])) != NULL)
        {
            avdt_scb_event(p_scb, event, (tAVDT_SCB_EVT *) &p_data->msg);
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_suspend_cmd
**
** Description      This function is called when a suspend command is received
**                  from the peer.  It verifies that all requested streams are
**                  in the proper state.  If so, it initiates sending of a
**                  suspend response.  Otherwise it sends a suspend reject.

**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_suspend_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8   seid;
    UINT8   err_code;

    /* verify all streams in the right state */
    if ((seid = avdt_scb_verify(p_ccb, AVDT_VERIFY_SUSPEND, p_data->msg.multi.seid_list,
                                p_data->msg.multi.num_seps, &err_code)) == 0)
    {
        /* we're ok, send response */
        avdt_ccb_event(p_ccb, AVDT_CCB_API_SUSPEND_RSP_EVT, p_data);
    }
    else
    {
        /* not ok, send reject */
        p_data->msg.hdr.err_code = err_code;
        p_data->msg.hdr.err_param = seid;
        avdt_msg_send_rej(p_ccb, AVDT_SIG_SUSPEND, &p_data->msg);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_hdl_suspend_rsp
**
** Description      This function is called when a suspend response or reject
**                  is received from the peer.  Using the SEIDs stored in the
**                  current command message, it sends a suspend response or
**                  suspend reject event to each SCB associated with the command.
**
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_hdl_suspend_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8       event;
    int         i;
    UINT8       *p;
    tAVDT_SCB   *p_scb;

    /* determine rsp or rej event */
    event = (p_data->msg.hdr.err_code == 0) ?
            AVDT_SCB_MSG_SUSPEND_RSP_EVT : AVDT_SCB_MSG_SUSPEND_REJ_EVT;

    /* get to where seid's are stashed in current cmd */
    p = (UINT8 *)(p_ccb->p_curr_cmd + 1);

    /* little trick here; length of current command equals number of streams */
    for (i = 0; i < p_ccb->p_curr_cmd->len; i++)
    {
        if ((p_scb = avdt_scb_by_hdl(p[i])) != NULL)
        {
            avdt_scb_event(p_scb, event, (tAVDT_SCB_EVT *) &p_data->msg);
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_discover_cmd
**
** Description      This function is called to send a discover command to the
**                  peer.  It copies variables needed for the procedure from
**                  the event to the CCB.  It marks the CCB as busy and then
**                  sends a discover command.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_discover_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* store info in ccb struct */
    p_ccb->p_proc_data = p_data->discover.p_sep_info;
    p_ccb->proc_cback = p_data->discover.p_cback;
    p_ccb->proc_param = p_data->discover.num_seps;

    /* we're busy */
    p_ccb->proc_busy = TRUE;

    /* build and queue discover req */
    avdt_msg_send_cmd(p_ccb, NULL, AVDT_SIG_DISCOVER, NULL);
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_discover_rsp
**
** Description      This function is called to send a discover response to
**                  the peer.  It takes the stream information passed in the
**                  event and sends a discover response.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_discover_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* send response */
    avdt_msg_send_rsp(p_ccb, AVDT_SIG_DISCOVER, &p_data->msg);
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_getcap_cmd
**
** Description      This function is called to send a get capabilities command
**                  to the peer.  It copies variables needed for the procedure
**                  from the event to the CCB.  It marks the CCB as busy and
**                  then sends a get capabilities command.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_getcap_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8 sig_id = AVDT_SIG_GETCAP;

    /* store info in ccb struct */
    p_ccb->p_proc_data = p_data->getcap.p_cfg;
    p_ccb->proc_cback = p_data->getcap.p_cback;

    /* we're busy */
    p_ccb->proc_busy = TRUE;

    /* build and queue discover req */
    if (p_data->msg.hdr.sig_id == AVDT_SIG_GET_ALLCAP)
        sig_id = AVDT_SIG_GET_ALLCAP;

    avdt_msg_send_cmd(p_ccb, NULL, sig_id, (tAVDT_MSG *) &p_data->getcap.single);
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_getcap_rsp
**
** Description      This function is called to send a get capabilities response
**                  to the peer.  It takes the stream information passed in the
**                  event and sends a get capabilities response.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_getcap_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8 sig_id = AVDT_SIG_GETCAP;

    if (p_data->msg.hdr.sig_id == AVDT_SIG_GET_ALLCAP)
        sig_id = AVDT_SIG_GET_ALLCAP;

    /* send response */
    avdt_msg_send_rsp(p_ccb, sig_id, &p_data->msg);
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_start_cmd
**
** Description      This function is called to send a start command to the
**                  peer.  It verifies that all requested streams are in the
**                  proper state.  If so, it sends a start command.  Otherwise
**                  send ourselves back a start reject.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_start_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    int             i;
    tAVDT_SCB       *p_scb;
    tAVDT_MSG       avdt_msg;
    UINT8           seid_list[AVDT_NUM_SEPS];

    /* make copy of our seid list */
    memcpy(seid_list, p_data->msg.multi.seid_list, p_data->msg.multi.num_seps);

    /* verify all streams in the right state */
    if ((avdt_msg.hdr.err_param = avdt_scb_verify(p_ccb, AVDT_VERIFY_OPEN, p_data->msg.multi.seid_list,
                                         p_data->msg.multi.num_seps, &avdt_msg.hdr.err_code)) == 0)
    {
        /* set peer seid list in messsage */
        avdt_scb_peer_seid_list(&p_data->msg.multi);

        /* send command */
        avdt_msg_send_cmd(p_ccb, seid_list, AVDT_SIG_START, &p_data->msg);
    }
    else
    {
        /* failed; send ourselves a reject for each stream */
        for (i = 0; i < p_data->msg.multi.num_seps; i++)
        {
            if ((p_scb = avdt_scb_by_hdl(seid_list[i])) != NULL)
            {
                avdt_scb_event(p_scb, AVDT_SCB_MSG_START_REJ_EVT, (tAVDT_SCB_EVT *) &avdt_msg.hdr);
            }
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_start_rsp
**
** Description      This function is called to send a start response to the
**                  peer.  It takes the stream information passed in the event
**                  and sends a start response.  Then it sends a start event
**                  to the SCB for each stream.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_start_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_SCB *p_scb;
    int i;

    /* send response message */
    avdt_msg_send_rsp(p_ccb, AVDT_SIG_START, &p_data->msg);

    /* send start event to each scb */
    for (i = 0; i < p_data->msg.multi.num_seps; i++)
    {
        if ((p_scb = avdt_scb_by_hdl(p_data->msg.multi.seid_list[i])) != NULL)
        {
            avdt_scb_event(p_scb, AVDT_SCB_MSG_START_CMD_EVT, NULL);
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_suspend_cmd
**
** Description      This function is called to send a suspend command to the
**                  peer.  It verifies that all requested streams are in the
**                  proper state.  If so, it sends a suspend command.
**                  Otherwise it calls the callback function for each requested
**                  stream and sends a suspend confirmation with failure.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_suspend_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    int             i;
    tAVDT_SCB       *p_scb;
    tAVDT_MSG       avdt_msg;
    UINT8           seid_list[AVDT_NUM_SEPS];

    /* make copy of our seid list */
    memcpy(seid_list, p_data->msg.multi.seid_list, p_data->msg.multi.num_seps);

    /* verify all streams in the right state */
    if ((avdt_msg.hdr.err_param = avdt_scb_verify(p_ccb, AVDT_VERIFY_STREAMING, p_data->msg.multi.seid_list,
                                         p_data->msg.multi.num_seps, &avdt_msg.hdr.err_code)) == 0)
    {
        /* set peer seid list in messsage */
        avdt_scb_peer_seid_list(&p_data->msg.multi);

        /* send command */
        avdt_msg_send_cmd(p_ccb, seid_list, AVDT_SIG_SUSPEND, &p_data->msg);
    }
    else
    {
        /* failed; send ourselves a reject for each stream */
        for (i = 0; i < p_data->msg.multi.num_seps; i++)
        {
            if ((p_scb = avdt_scb_by_hdl(seid_list[i])) != NULL)
            {
                avdt_scb_event(p_scb, AVDT_SCB_MSG_SUSPEND_REJ_EVT, (tAVDT_SCB_EVT *) &avdt_msg.hdr);
            }
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_suspend_rsp
**
** Description      This function is called to send a suspend response to the
**                  peer.  It takes the stream information passed in the event
**                  and sends a suspend response.  Then it sends a suspend event
**                  to the SCB for each stream.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_suspend_rsp(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_SCB *p_scb;
    int i;

    /* send response message */
    avdt_msg_send_rsp(p_ccb, AVDT_SIG_SUSPEND, &p_data->msg);

    /* send start event to each scb */
    for (i = 0; i < p_data->msg.multi.num_seps; i++)
    {
        if ((p_scb = avdt_scb_by_hdl(p_data->msg.multi.seid_list[i])) != NULL)
        {
            avdt_scb_event(p_scb, AVDT_SCB_MSG_SUSPEND_CMD_EVT, NULL);
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_clear_cmds
**
** Description      This function is called when the signaling channel is
**                  closed to clean up any pending commands.  For each pending
**                  command in the command queue, it frees the command and
**                  calls the application callback function indicating failure.
**                  Certain CCB variables are also initialized.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_clear_cmds(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    int             i;
    tAVDT_SCB       *p_scb = &avdt_cb.scb[0];
    UINT8           err_code = AVDT_ERR_CONNECT;

    /* clear the ccb */
    avdt_ccb_clear_ccb(p_ccb);

    /* clear out command queue; this is a little tricky here; we need
    ** to handle the case where there is a command on deck in p_curr_cmd,
    ** plus we need to clear out the queue
    */
    do
    {
        /* we know p_curr_cmd = NULL after this */
        avdt_ccb_cmd_fail(p_ccb, (tAVDT_CCB_EVT *) &err_code);

        /* set up next message */
        p_ccb->p_curr_cmd = (BT_HDR *) GKI_dequeue(&p_ccb->cmd_q);

    } while (p_ccb->p_curr_cmd != NULL);

    /* send a CC_CLOSE_EVT any active scbs associated with this ccb */
    for (i = 0; i < AVDT_NUM_SEPS; i++, p_scb++)
    {
        if ((p_scb->allocated) && (p_scb->p_ccb == p_ccb))
        {
            avdt_scb_event(p_scb, AVDT_SCB_CC_CLOSE_EVT, NULL);
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_cmd_fail
**
** Description      This function is called when there is a response timeout.
**                  The currently pending command is freed and we fake a
**                  reject message back to ourselves.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_cmd_fail(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_MSG       msg;
    UINT8           evt;
    tAVDT_SCB       *p_scb;

    if (p_ccb->p_curr_cmd != NULL)
    {
        /* set up data */
        msg.hdr.err_code = p_data->err_code;
        msg.hdr.err_param = 0;
        msg.hdr.ccb_idx = avdt_ccb_to_idx(p_ccb);

        /* pretend that we received a rej message */
        evt = avdt_msg_rej_2_evt[p_ccb->p_curr_cmd->event - 1];

        if (evt & AVDT_CCB_MKR)
        {
            avdt_ccb_event(p_ccb, (UINT8) (evt & ~AVDT_CCB_MKR), (tAVDT_CCB_EVT *) &msg);
        }
        else
        {
            /* we get the scb out of the current cmd */
            p_scb = avdt_scb_by_hdl(*((UINT8 *)(p_ccb->p_curr_cmd + 1)));
            if (p_scb != NULL)
            {
                avdt_scb_event(p_scb, evt, (tAVDT_SCB_EVT *) &msg);
            }
        }

        GKI_freebuf(p_ccb->p_curr_cmd);
        p_ccb->p_curr_cmd = NULL;
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_free_cmd
**
** Description      This function is called when a response is received for a
**                  currently pending command.  The command is freed.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_free_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    if (p_ccb->p_curr_cmd != NULL)
    {
        GKI_freebuf(p_ccb->p_curr_cmd);
        p_ccb->p_curr_cmd = NULL;
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_cong_state
**
** Description      This function is called to set the congestion state for
**                  the CCB.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_cong_state(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    p_ccb->cong = p_data->llcong;
}

/*******************************************************************************
**
** Function         avdt_ccb_ret_cmd
**
** Description      This function is called to retransmit the currently
**                  pending command.  The retransmission count is incremented.
**                  If the count reaches the maximum number of retransmissions,
**                  the event is treated as a response timeout.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_ret_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8   err_code = AVDT_ERR_TIMEOUT;
    BT_HDR  *p_msg;

    p_ccb->ret_count++;
    if (p_ccb->ret_count == AVDT_RET_MAX)
    {
        /* command failed */
        p_ccb->ret_count = 0;
        avdt_ccb_cmd_fail(p_ccb, (tAVDT_CCB_EVT *) &err_code);

        /* go to next queued command */
        avdt_ccb_snd_cmd(p_ccb, p_data);
    }
    else
    {
        /* if command pending and we're not congested and not sending a fragment */
        if ((!p_ccb->cong) && (p_ccb->p_curr_msg == NULL) && (p_ccb->p_curr_cmd != NULL))
        {
            /* make copy of message in p_curr_cmd and send it */
            if ((p_msg = (BT_HDR *) GKI_getpoolbuf(AVDT_CMD_POOL_ID)) != NULL)
            {
                memcpy(p_msg, p_ccb->p_curr_cmd,
                       (sizeof(BT_HDR) + p_ccb->p_curr_cmd->offset + p_ccb->p_curr_cmd->len));
                avdt_msg_send(p_ccb, p_msg);
            }
        }

        /* restart timer */
        btu_start_timer(&p_ccb->timer_entry, BTU_TTYPE_AVDT_CCB_RET, avdt_cb.rcb.ret_tout);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_cmd
**
** Description      This function is called the send the next command,
**                  if any, in the command queue.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_cmd(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    BT_HDR  *p_msg;

    /* do we have commands to send?  send next command;  make sure we're clear;
    ** not congested, not sending fragment, not waiting for response
    */
    if ((!p_ccb->cong) && (p_ccb->p_curr_msg == NULL) && (p_ccb->p_curr_cmd == NULL))
    {
        if ((p_msg = (BT_HDR *) GKI_dequeue(&p_ccb->cmd_q)) != NULL)
        {
            /* make a copy of buffer in p_curr_cmd */
            if ((p_ccb->p_curr_cmd = (BT_HDR *) GKI_getpoolbuf(AVDT_CMD_POOL_ID)) != NULL)
            {
                memcpy(p_ccb->p_curr_cmd, p_msg, (sizeof(BT_HDR) + p_msg->offset + p_msg->len));

                avdt_msg_send(p_ccb, p_msg);
            }
        }
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_snd_msg
**
** Description
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_snd_msg(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    BT_HDR      *p_msg;

    /* if not congested */
    if (!p_ccb->cong)
    {
        /* are we sending a fragmented message? continue sending fragment */
        if (p_ccb->p_curr_msg != NULL)
        {
            avdt_msg_send(p_ccb, NULL);
        }
        /* do we have responses to send?  send them */
        else if (!GKI_queue_is_empty(&p_ccb->rsp_q))
        {
            while ((p_msg = (BT_HDR *) GKI_dequeue(&p_ccb->rsp_q)) != NULL)
            {
                if (avdt_msg_send(p_ccb, p_msg) == TRUE)
                {
                    /* break out if congested */
                    break;
                }
            }
        }

        /* do we have commands to send?  send next command */
        avdt_ccb_snd_cmd(p_ccb, NULL);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_set_reconn
**
** Description      This function is called to enable a reconnect attempt when
**                  a channel transitions from closing to idle state.  It sets
**                  the reconn variable to TRUE.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_set_reconn(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    p_ccb->reconn = TRUE;
}

/*******************************************************************************
**
** Function         avdt_ccb_clr_reconn
**
** Description      This function is called to clear the reconn variable.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_clr_reconn(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    p_ccb->reconn = FALSE;
}

/*******************************************************************************
**
** Function         avdt_ccb_chk_reconn
**
** Description      This function is called to check if a reconnect attempt
**                  is enabled.  If enabled, it sends an AVDT_CCB_UL_OPEN_EVT
**                  to the CCB.  If disabled, the CCB is deallocated.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_chk_reconn(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    UINT8   err_code = AVDT_ERR_CONNECT;

    if (p_ccb->reconn)
    {
        p_ccb->reconn = FALSE;

        /* clear out ccb */
        avdt_ccb_clear_ccb(p_ccb);

        /* clear out current command, if any */
        avdt_ccb_cmd_fail(p_ccb, (tAVDT_CCB_EVT *) &err_code);

        /* reopen the signaling channel */
        avdt_ccb_event(p_ccb, AVDT_CCB_UL_OPEN_EVT, NULL);
    }
    else
    {
        avdt_ccb_ll_closed(p_ccb, NULL);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_chk_timer
**
** Description      This function stops the CCB timer if the idle timer is
**                  running.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_chk_timer(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    if (p_ccb->timer_entry.event == BTU_TTYPE_AVDT_CCB_IDLE)
    {
        btu_stop_timer(&p_ccb->timer_entry);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_set_conn
**
** Description      Set CCB variables associated with AVDT_ConnectReq().
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_set_conn(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* save callback */
    p_ccb->p_conn_cback = p_data->connect.p_cback;

    /* set security level */
    BTM_SetSecurityLevel(TRUE, "", BTM_SEC_SERVICE_AVDTP, p_data->connect.sec_mask,
                         AVDT_PSM, BTM_SEC_PROTO_AVDT, AVDT_CHAN_SIG);
}

/*******************************************************************************
**
** Function         avdt_ccb_set_disconn
**
** Description      Set CCB variables associated with AVDT_DisconnectReq().
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_set_disconn(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /*
    AVDT_TRACE_EVENT2("avdt_ccb_set_disconn:conn:x%x, api:x%x",
        p_ccb->p_conn_cback, p_data->disconnect.p_cback);
        */
    /* save callback */
    if (p_data->disconnect.p_cback)
        p_ccb->p_conn_cback = p_data->disconnect.p_cback;
}

/*******************************************************************************
**
** Function         avdt_ccb_do_disconn
**
** Description      Do action associated with AVDT_DisconnectReq().
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_do_disconn(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    /* clear any pending commands */
    avdt_ccb_clear_cmds(p_ccb, NULL);

    /* close channel */
    avdt_ccb_chan_close(p_ccb, NULL);
}

/*******************************************************************************
**
** Function         avdt_ccb_ll_closed
**
** Description      Clear commands from and deallocate CCB.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_ll_closed(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_CTRL_CBACK    *p_cback;
    BD_ADDR             bd_addr;
    tAVDT_CTRL          avdt_ctrl;

    /* clear any pending commands */
    avdt_ccb_clear_cmds(p_ccb, NULL);

    /* save callback pointer, bd addr */
    p_cback = p_ccb->p_conn_cback;
    if (!p_cback)
        p_cback = avdt_cb.p_conn_cback;
    memcpy(bd_addr, p_ccb->peer_addr, BD_ADDR_LEN);

    /* dealloc ccb */
    avdt_ccb_dealloc(p_ccb, NULL);

    /* call callback */
    if (p_cback)
    {
        avdt_ctrl.hdr.err_code = 0;
        (*p_cback)(0, bd_addr, AVDT_DISCONNECT_IND_EVT, &avdt_ctrl);
    }
}

/*******************************************************************************
**
** Function         avdt_ccb_ll_opened
**
** Description      Call callback on open.
**
**
** Returns          void.
**
*******************************************************************************/
void avdt_ccb_ll_opened(tAVDT_CCB *p_ccb, tAVDT_CCB_EVT *p_data)
{
    tAVDT_CTRL          avdt_ctrl;

    p_ccb->ll_opened = TRUE;

    if (!p_ccb->p_conn_cback)
        p_ccb->p_conn_cback = avdt_cb.p_conn_cback;

    /* call callback */
    if (p_ccb->p_conn_cback)
    {
        avdt_ctrl.hdr.err_code = 0;
        avdt_ctrl.hdr.err_param = p_data->msg.hdr.err_param;
        (*p_ccb->p_conn_cback)(0, p_ccb->peer_addr, AVDT_CONNECT_IND_EVT, &avdt_ctrl);
    }
}