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      1 /******************************************************************************
      2  *
      3  *  Copyright (C) 1999-2012 Broadcom Corporation
      4  *
      5  *  Licensed under the Apache License, Version 2.0 (the "License");
      6  *  you may not use this file except in compliance with the License.
      7  *  You may obtain a copy of the License at:
      8  *
      9  *  http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  *  Unless required by applicable law or agreed to in writing, software
     12  *  distributed under the License is distributed on an "AS IS" BASIS,
     13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  *  See the License for the specific language governing permissions and
     15  *  limitations under the License.
     16  *
     17  ******************************************************************************/
     18 
     19 /******************************************************************************
     20  *
     21  *  This module contains functions for port emulation entity and RFCOMM
     22  *  communications
     23  *
     24  ******************************************************************************/
     25 #include <string.h>
     26 
     27 #include "osi/include/mutex.h"
     28 #include "osi/include/osi.h"
     29 
     30 #include "bt_common.h"
     31 #include "bt_target.h"
     32 #include "bt_utils.h"
     33 #include "btm_api.h"
     34 #include "btm_int.h"
     35 #include "port_api.h"
     36 #include "port_int.h"
     37 #include "rfc_int.h"
     38 #include "rfcdefs.h"
     39 
     40 /*
     41  * Local function definitions
     42 */
     43 uint32_t port_rfc_send_tx_data(tPORT* p_port);
     44 void port_rfc_closed(tPORT* p_port, uint8_t res);
     45 void port_get_credits(tPORT* p_port, uint8_t k);
     46 
     47 /*******************************************************************************
     48  *
     49  * Function         port_open_continue
     50  *
     51  * Description      This function is called after security manager completes
     52  *                  required security checks.
     53  *
     54  * Returns          void
     55  *
     56  ******************************************************************************/
     57 int port_open_continue(tPORT* p_port) {
     58   tRFC_MCB* p_mcb;
     59 
     60   RFCOMM_TRACE_EVENT("port_open_continue, p_port:%p", p_port);
     61 
     62   /* Check if multiplexer channel has already been established */
     63   p_mcb = rfc_alloc_multiplexer_channel(p_port->bd_addr, true);
     64   if (p_mcb == NULL) {
     65     RFCOMM_TRACE_WARNING("port_open_continue no mx channel");
     66     port_release_port(p_port);
     67     return (PORT_NO_RESOURCES);
     68   }
     69 
     70   p_port->rfc.p_mcb = p_mcb;
     71 
     72   p_mcb->port_inx[p_port->dlci] = p_port->inx;
     73 
     74   /* Connection is up and we know local and remote features, select MTU */
     75   port_select_mtu(p_port);
     76 
     77   if (p_mcb->state == RFC_MX_STATE_CONNECTED) {
     78     RFCOMM_ParNegReq(p_mcb, p_port->dlci, p_port->mtu);
     79   } else if ((p_mcb->state == RFC_MX_STATE_IDLE) ||
     80              (p_mcb->state == RFC_MX_STATE_DISC_WAIT_UA)) {
     81     /* In RFC_MX_STATE_IDLE state, MX state machine will create connection */
     82     /* In RFC_MX_STATE_DISC_WAIT_UA state, MX state machine will recreate
     83      * connection */
     84     /*    after disconnecting is completed */
     85     RFCOMM_StartReq(p_mcb);
     86   } else {
     87     /* MX state machine ignores RFC_MX_EVENT_START_REQ in these states */
     88     /* When it enters RFC_MX_STATE_CONNECTED, it will check any openning ports
     89      */
     90     RFCOMM_TRACE_DEBUG(
     91         "port_open_continue: mx state(%d) mx channel is openning",
     92         p_mcb->state);
     93   }
     94   return (PORT_SUCCESS);
     95 }
     96 
     97 /*******************************************************************************
     98  *
     99  * Function         port_start_control
    100  *
    101  * Description      This function is called in the BTU_TASK context to
    102  *                  send control information
    103  *
    104  * Returns          void
    105  *
    106  ******************************************************************************/
    107 void port_start_control(tPORT* p_port) {
    108   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    109 
    110   if (p_mcb == NULL) return;
    111 
    112   RFCOMM_ControlReq(p_mcb, p_port->dlci, &p_port->local_ctrl);
    113 }
    114 
    115 /*******************************************************************************
    116  *
    117  * Function         port_start_par_neg
    118  *
    119  * Description      This function is called in the BTU_TASK context to
    120  *                  send configuration information
    121  *
    122  * Returns          void
    123  *
    124  ******************************************************************************/
    125 void port_start_par_neg(tPORT* p_port) {
    126   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    127 
    128   if (p_mcb == NULL) return;
    129 
    130   RFCOMM_PortNegReq(p_mcb, p_port->dlci, &p_port->user_port_pars);
    131 }
    132 
    133 /*******************************************************************************
    134  *
    135  * Function         port_start_close
    136  *
    137  * Description      This function is called in the BTU_TASK context to
    138  *                  release DLC
    139  *
    140  * Returns          void
    141  *
    142  ******************************************************************************/
    143 void port_start_close(tPORT* p_port) {
    144   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    145   uint8_t old_signals;
    146   uint32_t events = 0;
    147 
    148   /* At first indicate to the user that signals on the connection were dropped
    149    */
    150   p_port->line_status |= LINE_STATUS_FAILED;
    151   old_signals = p_port->peer_ctrl.modem_signal;
    152 
    153   p_port->peer_ctrl.modem_signal &=
    154       ~(PORT_DTRDSR_ON | PORT_CTSRTS_ON | PORT_DCD_ON);
    155 
    156   events |= port_get_signal_changes(p_port, old_signals,
    157                                     p_port->peer_ctrl.modem_signal);
    158 
    159   if (p_port->ev_mask & PORT_EV_CONNECT_ERR) events |= PORT_EV_CONNECT_ERR;
    160 
    161   if (p_port->ev_mask & PORT_EV_ERR) events |= PORT_EV_ERR;
    162 
    163   if ((p_port->p_callback != NULL) && events)
    164     p_port->p_callback(events, p_port->inx);
    165 
    166   /* Check if RFCOMM side has been closed while the message was queued */
    167   if ((p_mcb == NULL) || (p_port->rfc.state == RFC_STATE_CLOSED)) {
    168     /* Call management callback function before calling port_release_port() to
    169      * clear tPort */
    170     if (p_port->p_mgmt_callback)
    171       p_port->p_mgmt_callback(PORT_CLOSED, p_port->inx);
    172 
    173     port_release_port(p_port);
    174   } else {
    175     RFCOMM_DlcReleaseReq(p_mcb, p_port->dlci);
    176   }
    177 }
    178 
    179 /*******************************************************************************
    180  *
    181  * Function         PORT_StartCnf
    182  *
    183  * Description      This function is called from the RFCOMM layer when
    184  *                  establishing of the multiplexer channel is completed.
    185  *                  Continue establishing of the connection for all ports that
    186  *                  are in the OPENING state
    187  *
    188  ******************************************************************************/
    189 void PORT_StartCnf(tRFC_MCB* p_mcb, uint16_t result) {
    190   tPORT* p_port;
    191   int i;
    192   bool no_ports_up = true;
    193 
    194   RFCOMM_TRACE_EVENT("PORT_StartCnf result:%d", result);
    195 
    196   p_port = &rfc_cb.port.port[0];
    197   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    198     if (p_port->rfc.p_mcb == p_mcb) {
    199       no_ports_up = false;
    200 
    201       if (result == RFCOMM_SUCCESS)
    202         RFCOMM_ParNegReq(p_mcb, p_port->dlci, p_port->mtu);
    203       else {
    204         RFCOMM_TRACE_WARNING("PORT_StartCnf failed result:%d", result);
    205 
    206         /* Warning: result is also set to 4 when l2cap connection
    207            fails due to l2cap connect cnf (no_resources) */
    208         if (result == HCI_ERR_PAGE_TIMEOUT)
    209           p_port->error = PORT_PAGE_TIMEOUT;
    210         else
    211           p_port->error = PORT_START_FAILED;
    212 
    213         rfc_release_multiplexer_channel(p_mcb);
    214 
    215         /* Send event to the application */
    216         if (p_port->p_callback && (p_port->ev_mask & PORT_EV_CONNECT_ERR))
    217           (p_port->p_callback)(PORT_EV_CONNECT_ERR, p_port->inx);
    218 
    219         if (p_port->p_mgmt_callback)
    220           p_port->p_mgmt_callback(PORT_START_FAILED, p_port->inx);
    221 
    222         port_release_port(p_port);
    223       }
    224     }
    225   }
    226 
    227   /* There can be a situation when after starting connection, user closes the */
    228   /* port, we can catch it here to close multiplexor channel */
    229   if (no_ports_up) {
    230     rfc_check_mcb_active(p_mcb);
    231   }
    232 }
    233 
    234 /*******************************************************************************
    235  *
    236  * Function         PORT_StartInd
    237  *
    238  * Description      This function is called from the RFCOMM layer when
    239  *                  some peer device wants to establish a multiplexer
    240  *                  connection.  Check if there are any ports open with this
    241  *                  or not assigned multiplexer.
    242  *
    243  ******************************************************************************/
    244 void PORT_StartInd(tRFC_MCB* p_mcb) {
    245   tPORT* p_port;
    246   int i;
    247 
    248   RFCOMM_TRACE_EVENT("PORT_StartInd");
    249 
    250   p_port = &rfc_cb.port.port[0];
    251   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    252     if ((p_port->rfc.p_mcb == NULL) || (p_port->rfc.p_mcb == p_mcb)) {
    253       RFCOMM_TRACE_DEBUG(
    254           "PORT_StartInd, RFCOMM_StartRsp RFCOMM_SUCCESS: p_mcb:%p", p_mcb);
    255       RFCOMM_StartRsp(p_mcb, RFCOMM_SUCCESS);
    256       return;
    257     }
    258   }
    259   RFCOMM_StartRsp(p_mcb, RFCOMM_ERROR);
    260 }
    261 
    262 /*******************************************************************************
    263  *
    264  * Function         PORT_ParNegInd
    265  *
    266  * Description      This function is called from the RFCOMM layer to change
    267  *                  DLCI parameters (currently only MTU is negotiated).
    268  *                  If can not find the port do not accept the request.
    269  *                  Otherwise save the MTU size supported by the peer.
    270  *
    271  ******************************************************************************/
    272 void PORT_ParNegInd(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu, uint8_t cl,
    273                     uint8_t k) {
    274   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    275   uint8_t our_cl;
    276   uint8_t our_k;
    277 
    278   RFCOMM_TRACE_EVENT("PORT_ParNegInd dlci:%d mtu:%d", dlci, mtu);
    279 
    280   if (!p_port) {
    281     /* This can be a first request for this port */
    282     p_port = port_find_dlci_port(dlci);
    283     if (!p_port) {
    284       /* If the port cannot be opened, send a DM.  Per Errata 1205 */
    285       rfc_send_dm(p_mcb, dlci, false);
    286       /* check if this is the last port open, some headsets have
    287       problem, they don't disconnect if we send DM */
    288       rfc_check_mcb_active(p_mcb);
    289       RFCOMM_TRACE_EVENT("PORT_ParNegInd: port not found");
    290       return;
    291     }
    292     p_mcb->port_inx[dlci] = p_port->inx;
    293   }
    294 
    295   memcpy(p_port->bd_addr, p_mcb->bd_addr, BD_ADDR_LEN);
    296 
    297   /* Connection is up and we know local and remote features, select MTU */
    298   port_select_mtu(p_port);
    299 
    300   p_port->rfc.p_mcb = p_mcb;
    301   p_port->mtu = (p_port->mtu < mtu) ? p_port->mtu : mtu;
    302   p_port->peer_mtu = p_port->mtu;
    303 
    304   /* Negotiate the flow control mechanism.  If flow control mechanism for */
    305   /* mux has not been set yet, set it now.  If either we or peer wants TS 07.10,
    306    */
    307   /* use that.  Otherwise both must want credit based, so use that. If flow is
    308    */
    309   /* already defined for this mux, we respond with that value. */
    310   if (p_mcb->flow == PORT_FC_UNDEFINED) {
    311     if ((PORT_FC_DEFAULT == PORT_FC_TS710) ||
    312         (cl == RFCOMM_PN_CONV_LAYER_TYPE_1)) {
    313       p_mcb->flow = PORT_FC_TS710;
    314     } else {
    315       p_mcb->flow = PORT_FC_CREDIT;
    316     }
    317   }
    318 
    319   /* Regardless of our flow control mechanism, if the PN cl is zero, we must */
    320   /* respond with zero.  "A responding implementation must set this field to 14
    321    */
    322   /* if (and only if) the PN request was 15."  This could happen if a PN is sent
    323    */
    324   /* after the DLCI is already established-- the PN in that case must have cl =
    325    * 0. */
    326   /* See RFCOMM spec 5.5.3 */
    327   if (cl == RFCOMM_PN_CONV_LAYER_TYPE_1) {
    328     our_cl = RFCOMM_PN_CONV_LAYER_TYPE_1;
    329     our_k = 0;
    330   } else if (p_mcb->flow == PORT_FC_CREDIT) {
    331     /* get credits */
    332     port_get_credits(p_port, k);
    333 
    334     /* Set convergence layer and number of credits (k) */
    335     our_cl = RFCOMM_PN_CONV_LAYER_CBFC_R;
    336     our_k = (p_port->credit_rx_max < RFCOMM_K_MAX) ? p_port->credit_rx_max
    337                                                    : RFCOMM_K_MAX;
    338     p_port->credit_rx = our_k;
    339   } else {
    340     /* must not be using credit based flow control; use TS 7.10 */
    341     our_cl = RFCOMM_PN_CONV_LAYER_TYPE_1;
    342     our_k = 0;
    343   }
    344   RFCOMM_ParNegRsp(p_mcb, dlci, p_port->mtu, our_cl, our_k);
    345 }
    346 
    347 /*******************************************************************************
    348  *
    349  * Function         PORT_ParNegCnf
    350  *
    351  * Description      This function is called from the RFCOMM layer to change
    352  *                  DLCI parameters (currently only MTU is negotiated).
    353  *                  Save the MTU size supported by the peer.
    354  *                  If the confirmation is received during the port opening
    355  *                  procedure send EstablishRequest to continue.
    356  *
    357  ******************************************************************************/
    358 void PORT_ParNegCnf(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu, uint8_t cl,
    359                     uint8_t k) {
    360   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    361 
    362   RFCOMM_TRACE_EVENT("PORT_ParNegCnf dlci:%d mtu:%d cl: %d k: %d", dlci, mtu,
    363                      cl, k);
    364 
    365   if (!p_port) return;
    366 
    367   /* Flow control mechanism not set yet.  Negotiate flow control mechanism. */
    368   if (p_mcb->flow == PORT_FC_UNDEFINED) {
    369     /* Our stack is configured for TS07.10 and they responded with credit-based.
    370      */
    371     /* This is illegal-- negotiation fails. */
    372     if ((PORT_FC_DEFAULT == PORT_FC_TS710) &&
    373         (cl == RFCOMM_PN_CONV_LAYER_CBFC_R)) {
    374       rfc_send_disc(p_mcb, p_port->dlci);
    375       rfc_port_closed(p_port);
    376       return;
    377     }
    378     /* Our stack is configured for credit-based and they responded with
    379        credit-based. */
    380     else if (cl == RFCOMM_PN_CONV_LAYER_CBFC_R) {
    381       p_mcb->flow = PORT_FC_CREDIT;
    382     }
    383     /* They responded with any other value.  Treat this as negotiation to
    384        TS07.10. */
    385     else {
    386       p_mcb->flow = PORT_FC_TS710;
    387     }
    388   }
    389   /* If mux flow control mechanism set, we honor that setting regardless of */
    390   /* the CL value in their response.  This allows us to gracefully accept any */
    391   /* illegal PN negotiation scenarios. */
    392 
    393   p_port->mtu = (p_port->mtu < mtu) ? p_port->mtu : mtu;
    394   p_port->peer_mtu = p_port->mtu;
    395 
    396   if (p_mcb->flow == PORT_FC_CREDIT) {
    397     port_get_credits(p_port, k);
    398   }
    399 
    400   if (p_port->state == PORT_STATE_OPENING)
    401     RFCOMM_DlcEstablishReq(p_mcb, p_port->dlci, p_port->mtu);
    402 }
    403 
    404 /*******************************************************************************
    405  *
    406  * Function         PORT_DlcEstablishInd
    407  *
    408  * Description      This function is called from the RFCOMM layer when peer
    409  *                  device wants to establish a new DLC.  If this is not the
    410  *                  first message in the establishment procedure port_handle
    411  *                  has a handle to the port control block otherwise the control
    412  *                  block should be found based on the muliplexer channel and
    413  *                  dlci.  The block should be allocated allocated before
    414  *                  meaning that application already made open.
    415  *
    416  ******************************************************************************/
    417 void PORT_DlcEstablishInd(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu) {
    418   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    419 
    420   RFCOMM_TRACE_DEBUG(
    421       "PORT_DlcEstablishInd p_mcb:%p, dlci:%d mtu:%di, p_port:%p", p_mcb, dlci,
    422       mtu, p_port);
    423   RFCOMM_TRACE_DEBUG(
    424       "PORT_DlcEstablishInd p_mcb addr:%02x:%02x:%02x:%02x:%02x:%02x",
    425       p_mcb->bd_addr[0], p_mcb->bd_addr[1], p_mcb->bd_addr[2],
    426       p_mcb->bd_addr[3], p_mcb->bd_addr[4], p_mcb->bd_addr[5]);
    427 
    428   if (!p_port) {
    429     /* This can be a first request for this port */
    430     p_port = port_find_dlci_port(dlci);
    431     if (!p_port) {
    432       RFCOMM_DlcEstablishRsp(p_mcb, dlci, 0, RFCOMM_ERROR);
    433       return;
    434     }
    435     p_mcb->port_inx[dlci] = p_port->inx;
    436   }
    437 
    438   /* If L2CAP's mtu less then RFCOMM's take it */
    439   if (mtu && (mtu < p_port->peer_mtu)) p_port->peer_mtu = mtu;
    440 
    441   /* If there was an inactivity timer running for MCB stop it */
    442   rfc_timer_stop(p_mcb);
    443 
    444   RFCOMM_DlcEstablishRsp(p_mcb, dlci, p_port->mtu, RFCOMM_SUCCESS);
    445 
    446   /* This is the server side.  If application wants to know when connection */
    447   /* is established, thats the place */
    448   if (p_port->p_callback && (p_port->ev_mask & PORT_EV_CONNECTED))
    449     (p_port->p_callback)(PORT_EV_CONNECTED, p_port->inx);
    450 
    451   if (p_port->p_mgmt_callback)
    452     p_port->p_mgmt_callback(PORT_SUCCESS, p_port->inx);
    453 
    454   p_port->state = PORT_STATE_OPENED;
    455 }
    456 
    457 /*******************************************************************************
    458  *
    459  * Function         PORT_DlcEstablishCnf
    460  *
    461  * Description      This function is called from the RFCOMM layer when peer
    462  *                  acknowledges establish procedure (SABME/UA).  Send reply
    463  *                  to the user and set state to OPENED if result was
    464  *                  successfull.
    465  *
    466  ******************************************************************************/
    467 void PORT_DlcEstablishCnf(tRFC_MCB* p_mcb, uint8_t dlci, uint16_t mtu,
    468                           uint16_t result) {
    469   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    470 
    471   RFCOMM_TRACE_EVENT("PORT_DlcEstablishCnf dlci:%d mtu:%d result:%d", dlci, mtu,
    472                      result);
    473 
    474   if (!p_port) return;
    475 
    476   if (result != RFCOMM_SUCCESS) {
    477     p_port->error = PORT_START_FAILED;
    478     port_rfc_closed(p_port, PORT_START_FAILED);
    479     return;
    480   }
    481 
    482   /* If L2CAP's mtu less then RFCOMM's take it */
    483   if (mtu && (mtu < p_port->peer_mtu)) p_port->peer_mtu = mtu;
    484 
    485   /* If there was an inactivity timer running for MCB stop it */
    486   rfc_timer_stop(p_mcb);
    487 
    488   if (p_port->p_callback && (p_port->ev_mask & PORT_EV_CONNECTED))
    489     (p_port->p_callback)(PORT_EV_CONNECTED, p_port->inx);
    490 
    491   if (p_port->p_mgmt_callback)
    492     p_port->p_mgmt_callback(PORT_SUCCESS, p_port->inx);
    493 
    494   p_port->state = PORT_STATE_OPENED;
    495 
    496   /* RPN is required only if we want to tell DTE how the port should be opened
    497    */
    498   if ((p_port->uuid == UUID_SERVCLASS_DIALUP_NETWORKING) ||
    499       (p_port->uuid == UUID_SERVCLASS_FAX))
    500     RFCOMM_PortNegReq(p_port->rfc.p_mcb, p_port->dlci, NULL);
    501   else
    502     RFCOMM_ControlReq(p_port->rfc.p_mcb, p_port->dlci, &p_port->local_ctrl);
    503 }
    504 
    505 /*******************************************************************************
    506  *
    507  * Function         PORT_PortNegInd
    508  *
    509  * Description      This function is called from the RFCOMM layer when peer
    510  *                  device wants to set parameters of the port.  As per the spec
    511  *                  this message has to be sent before the first data packet
    512  *                  and can be sent before establish.  The block should be
    513  *                  allocated before meaning that application already made open.
    514  *
    515  ******************************************************************************/
    516 void PORT_PortNegInd(tRFC_MCB* p_mcb, uint8_t dlci, tPORT_STATE* p_pars,
    517                      uint16_t param_mask) {
    518   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    519 
    520   RFCOMM_TRACE_EVENT("PORT_PortNegInd");
    521 
    522   if (!p_port) {
    523     /* This can be a first request for this port */
    524     p_port = port_find_dlci_port(dlci);
    525     if (!p_port) {
    526       RFCOMM_PortNegRsp(p_mcb, dlci, p_pars, 0);
    527       return;
    528     }
    529     p_mcb->port_inx[dlci] = p_port->inx;
    530   }
    531 
    532   /* Check if the flow control is acceptable on local side */
    533   p_port->peer_port_pars = *p_pars;
    534   RFCOMM_PortNegRsp(p_mcb, dlci, p_pars, param_mask);
    535 }
    536 
    537 /*******************************************************************************
    538  *
    539  * Function         PORT_PortNegCnf
    540  *
    541  * Description      This function is called from the RFCOMM layer to change
    542  *                  state for the port.  Propagate change to the user.
    543  *
    544  ******************************************************************************/
    545 void PORT_PortNegCnf(tRFC_MCB* p_mcb, uint8_t dlci,
    546                      UNUSED_ATTR tPORT_STATE* p_pars, uint16_t result) {
    547   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    548 
    549   RFCOMM_TRACE_EVENT("PORT_PortNegCnf");
    550 
    551   if (!p_port) {
    552     RFCOMM_TRACE_WARNING("PORT_PortNegCnf no port");
    553     return;
    554   }
    555   /* Port negotiation failed. Drop the connection */
    556   if (result != RFCOMM_SUCCESS) {
    557     p_port->error = PORT_PORT_NEG_FAILED;
    558 
    559     RFCOMM_DlcReleaseReq(p_mcb, p_port->dlci);
    560 
    561     port_rfc_closed(p_port, PORT_PORT_NEG_FAILED);
    562     return;
    563   }
    564 
    565   if (!(p_port->port_ctrl & PORT_CTRL_REQ_SENT)) {
    566     RFCOMM_ControlReq(p_port->rfc.p_mcb, p_port->dlci, &p_port->local_ctrl);
    567   } else {
    568     RFCOMM_TRACE_WARNING("PORT_PortNegCnf Control Already sent");
    569   }
    570 }
    571 
    572 /*******************************************************************************
    573  *
    574  * Function         PORT_ControlInd
    575  *
    576  * Description      This function is called from the RFCOMM layer on the modem
    577  *                  signal change.  Propagate change to the user.
    578  *
    579  ******************************************************************************/
    580 void PORT_ControlInd(tRFC_MCB* p_mcb, uint8_t dlci, tPORT_CTRL* p_pars) {
    581   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    582   uint32_t event;
    583   uint8_t old_signals;
    584 
    585   RFCOMM_TRACE_EVENT("PORT_ControlInd");
    586 
    587   if (!p_port) return;
    588 
    589   old_signals = p_port->peer_ctrl.modem_signal;
    590 
    591   event = port_get_signal_changes(p_port, old_signals, p_pars->modem_signal);
    592 
    593   p_port->peer_ctrl = *p_pars;
    594 
    595   if (!(p_port->port_ctrl & PORT_CTRL_REQ_SENT))
    596     RFCOMM_ControlReq(p_port->rfc.p_mcb, p_port->dlci, &p_port->local_ctrl);
    597   else {
    598     /* If this is the first time we received control RFCOMM is connected */
    599     if (!(p_port->port_ctrl & PORT_CTRL_IND_RECEIVED)) {
    600       event |= (PORT_EV_CONNECTED & p_port->ev_mask);
    601     }
    602 
    603     if (p_port->port_ctrl & PORT_CTRL_REQ_CONFIRMED) {
    604       event |= port_rfc_send_tx_data(p_port);
    605     }
    606   }
    607 
    608   p_port->port_ctrl |= (PORT_CTRL_IND_RECEIVED | PORT_CTRL_IND_RESPONDED);
    609 
    610   if (p_pars->break_signal) event |= (PORT_EV_BREAK & p_port->ev_mask);
    611 
    612   /* execute call back function only if the application is registered for events
    613    */
    614   if (event && p_port->p_callback) (p_port->p_callback)(event, p_port->inx);
    615 
    616   RFCOMM_TRACE_EVENT(
    617       "PORT_ControlInd DTR_DSR : %d, RTS_CTS : %d, RI : %d, DCD : %d",
    618       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_DTRDSR) ? 1 : 0),
    619       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_RTSCTS) ? 1 : 0),
    620       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_RI) ? 1 : 0),
    621       ((p_port->peer_ctrl.modem_signal & MODEM_SIGNAL_DCD) ? 1 : 0));
    622 }
    623 
    624 /*******************************************************************************
    625  *
    626  * Function         PORT_ControlCnf
    627  *
    628  * Description      This function is called from the RFCOMM layer when
    629  *                  peer acknowleges change of the modem signals.
    630  *
    631  ******************************************************************************/
    632 void PORT_ControlCnf(tRFC_MCB* p_mcb, uint8_t dlci,
    633                      UNUSED_ATTR tPORT_CTRL* p_pars) {
    634   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    635   uint32_t event = 0;
    636 
    637   RFCOMM_TRACE_EVENT("PORT_ControlCnf");
    638 
    639   if (!p_port) return;
    640 
    641   if (!(p_port->port_ctrl & PORT_CTRL_REQ_CONFIRMED)) {
    642     p_port->port_ctrl |= PORT_CTRL_REQ_CONFIRMED;
    643 
    644     if (p_port->port_ctrl & PORT_CTRL_IND_RECEIVED)
    645       event = (p_port->ev_mask & PORT_EV_CONNECTED);
    646   }
    647 
    648   if (p_port->port_ctrl & PORT_CTRL_IND_RECEIVED) {
    649     event |= port_rfc_send_tx_data(p_port);
    650   }
    651 
    652   /* execute call back function only if the application is registered for events
    653    */
    654   if (event && p_port->p_callback) (p_port->p_callback)(event, p_port->inx);
    655 }
    656 
    657 /*******************************************************************************
    658  *
    659  * Function         PORT_LineStatusInd
    660  *
    661  * Description      This function is called from the RFCOMM layer when
    662  *                  peer indicates change in the line status
    663  *
    664  ******************************************************************************/
    665 void PORT_LineStatusInd(tRFC_MCB* p_mcb, uint8_t dlci, uint8_t line_status) {
    666   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    667   uint32_t event = 0;
    668 
    669   RFCOMM_TRACE_EVENT("PORT_LineStatusInd");
    670 
    671   if (!p_port) return;
    672 
    673   p_port->line_status |= line_status;
    674 
    675   if (line_status & PORT_ERR_OVERRUN) event |= PORT_EV_OVERRUN;
    676 
    677   if (line_status & PORT_ERR_BREAK) event |= PORT_EV_BREAK;
    678 
    679   if (line_status & ~(PORT_ERR_OVERRUN | PORT_ERR_BREAK)) event |= PORT_EV_ERR;
    680 
    681   if ((p_port->p_callback != NULL) && (p_port->ev_mask & event))
    682     p_port->p_callback((p_port->ev_mask & event), p_port->inx);
    683 }
    684 
    685 /*******************************************************************************
    686  *
    687  * Function         PORT_DlcReleaseInd
    688  *
    689  * Description      This function is called from the RFCOMM layer when
    690  *                  DLC connection is released.
    691  *
    692  ******************************************************************************/
    693 void PORT_DlcReleaseInd(tRFC_MCB* p_mcb, uint8_t dlci) {
    694   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    695 
    696   RFCOMM_TRACE_EVENT("PORT_DlcReleaseInd");
    697 
    698   if (!p_port) return;
    699 
    700   port_rfc_closed(p_port, PORT_CLOSED);
    701 }
    702 
    703 /*******************************************************************************
    704  *
    705  * Function         PORT_CloseInd
    706  *
    707  * Description      This function is called from the RFCOMM layer when
    708  *                  multiplexer connection is released.
    709  *
    710  ******************************************************************************/
    711 void PORT_CloseInd(tRFC_MCB* p_mcb) {
    712   tPORT* p_port;
    713   int i;
    714 
    715   RFCOMM_TRACE_EVENT("PORT_CloseInd");
    716 
    717   p_port = &rfc_cb.port.port[0];
    718   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    719     if (p_port->rfc.p_mcb == p_mcb) {
    720       port_rfc_closed(p_port, PORT_PEER_CONNECTION_FAILED);
    721     }
    722   }
    723   rfc_release_multiplexer_channel(p_mcb);
    724 }
    725 
    726 /*******************************************************************************
    727  *
    728  * Function         Port_TimeOutCloseMux
    729  *
    730  * Description      This function is called when RFCOMM timesout on a command
    731  *                  as a result multiplexer connection is closed.
    732  *
    733  ******************************************************************************/
    734 void Port_TimeOutCloseMux(tRFC_MCB* p_mcb) {
    735   tPORT* p_port;
    736   int i;
    737 
    738   RFCOMM_TRACE_EVENT("Port_TimeOutCloseMux");
    739 
    740   p_port = &rfc_cb.port.port[0];
    741   for (i = 0; i < MAX_RFC_PORTS; i++, p_port++) {
    742     if (p_port->rfc.p_mcb == p_mcb) {
    743       port_rfc_closed(p_port, PORT_PEER_TIMEOUT);
    744     }
    745   }
    746 }
    747 
    748 /*******************************************************************************
    749  *
    750  * Function         PORT_DataInd
    751  *
    752  * Description      This function is called from the RFCOMM layer when data
    753  *                  buffer is received from the peer.
    754  *
    755  ******************************************************************************/
    756 void PORT_DataInd(tRFC_MCB* p_mcb, uint8_t dlci, BT_HDR* p_buf) {
    757   tPORT* p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    758   uint8_t rx_char1;
    759   uint32_t events = 0;
    760   uint8_t* p;
    761   int i;
    762 
    763   RFCOMM_TRACE_EVENT(
    764       "PORT_DataInd with data length %d, p_mcb:%p,p_port:%p,dlci:%d",
    765       p_buf->len, p_mcb, p_port, dlci);
    766   if (!p_port) {
    767     osi_free(p_buf);
    768     return;
    769   }
    770   /* If client registered callout callback with flow control we can just deliver
    771    * receive data */
    772   if (p_port->p_data_co_callback) {
    773     /* Another packet is delivered to user.  Send credits to peer if required */
    774     if (p_port->p_data_co_callback(p_port->inx, (uint8_t*)p_buf, -1,
    775                                    DATA_CO_CALLBACK_TYPE_INCOMING)) {
    776       port_flow_control_peer(p_port, true, 1);
    777     } else {
    778       port_flow_control_peer(p_port, false, 0);
    779     }
    780     // osi_free(p_buf);
    781     return;
    782   }
    783   /* If client registered callback we can just deliver receive data */
    784   if (p_port->p_data_callback) {
    785     /* Another packet is delivered to user.  Send credits to peer if required */
    786     port_flow_control_peer(p_port, true, 1);
    787     p_port->p_data_callback(p_port->inx, (uint8_t*)(p_buf + 1) + p_buf->offset,
    788                             p_buf->len);
    789     osi_free(p_buf);
    790     return;
    791   }
    792   /* Check if rx queue exceeds the limit */
    793   if ((p_port->rx.queue_size + p_buf->len > PORT_RX_CRITICAL_WM) ||
    794       (fixed_queue_length(p_port->rx.queue) + 1 > p_port->rx_buf_critical)) {
    795     RFCOMM_TRACE_EVENT("PORT_DataInd. Buffer over run. Dropping the buffer");
    796     osi_free(p_buf);
    797     RFCOMM_LineStatusReq(p_mcb, dlci, LINE_STATUS_OVERRUN);
    798     return;
    799   }
    800   /* If user registered to receive notification when a particular byte is */
    801   /* received we mast check all received bytes */
    802   if (((rx_char1 = p_port->user_port_pars.rx_char1) != 0) &&
    803       (p_port->ev_mask & PORT_EV_RXFLAG)) {
    804     for (i = 0, p = (uint8_t*)(p_buf + 1) + p_buf->offset; i < p_buf->len;
    805          i++) {
    806       if (*p++ == rx_char1) {
    807         events |= PORT_EV_RXFLAG;
    808         break;
    809       }
    810     }
    811   }
    812 
    813   mutex_global_lock();
    814 
    815   fixed_queue_enqueue(p_port->rx.queue, p_buf);
    816   p_port->rx.queue_size += p_buf->len;
    817 
    818   mutex_global_unlock();
    819 
    820   /* perform flow control procedures if necessary */
    821   port_flow_control_peer(p_port, false, 0);
    822 
    823   /* If user indicated flow control can not deliver any notifications to him */
    824   if (p_port->rx.user_fc) {
    825     if (events & PORT_EV_RXFLAG) {
    826       p_port->rx_flag_ev_pending = true;
    827     }
    828     return;
    829   }
    830 
    831   events |= PORT_EV_RXCHAR;
    832 
    833   /* Mask out all events that are not of interest to user */
    834   events &= p_port->ev_mask;
    835 
    836   if (p_port->p_callback && events) p_port->p_callback(events, p_port->inx);
    837 }
    838 
    839 /*******************************************************************************
    840  *
    841  * Function         PORT_FlowInd
    842  *
    843  * Description      This function is called from the RFCOMM layer on the flow
    844  *                  control signal change.  Propagate change to the user.
    845  *
    846  ******************************************************************************/
    847 void PORT_FlowInd(tRFC_MCB* p_mcb, uint8_t dlci, bool enable_data) {
    848   tPORT* p_port = (tPORT*)NULL;
    849   uint32_t events = 0;
    850   int i;
    851 
    852   RFCOMM_TRACE_EVENT("PORT_FlowInd fc:%d", enable_data);
    853 
    854   if (dlci == 0) {
    855     p_mcb->peer_ready = enable_data;
    856   } else {
    857     p_port = port_find_mcb_dlci_port(p_mcb, dlci);
    858     if (p_port == NULL) return;
    859 
    860     p_port->tx.peer_fc = !enable_data;
    861   }
    862 
    863   for (i = 0; i < MAX_RFC_PORTS; i++) {
    864     /* If DLCI is 0 event applies to all ports */
    865     if (dlci == 0) {
    866       p_port = &rfc_cb.port.port[i];
    867       if (!p_port->in_use || (p_port->rfc.p_mcb != p_mcb) ||
    868           (p_port->rfc.state != RFC_STATE_OPENED))
    869         continue;
    870     }
    871     events = 0;
    872 
    873     /* Check if flow of data is still enabled */
    874     events |= port_flow_control_user(p_port);
    875 
    876     /* Check if data can be sent and send it */
    877     events |= port_rfc_send_tx_data(p_port);
    878 
    879     /* Mask out all events that are not of interest to user */
    880     events &= p_port->ev_mask;
    881 
    882     /* Send event to the application */
    883     if (p_port->p_callback && events) (p_port->p_callback)(events, p_port->inx);
    884 
    885     /* If DLCI is not 0 event applies to one port only */
    886     if (dlci != 0) break;
    887   }
    888 }
    889 
    890 /*******************************************************************************
    891  *
    892  * Function         port_rfc_send_tx_data
    893  *
    894  * Description      This function is when forward data can be sent to the peer
    895  *
    896  ******************************************************************************/
    897 uint32_t port_rfc_send_tx_data(tPORT* p_port) {
    898   uint32_t events = 0;
    899   BT_HDR* p_buf;
    900 
    901   /* if there is data to be sent */
    902   if (p_port->tx.queue_size > 0) {
    903     /* while the rfcomm peer is not flow controlling us, and peer is ready */
    904     while (!p_port->tx.peer_fc && p_port->rfc.p_mcb &&
    905            p_port->rfc.p_mcb->peer_ready) {
    906       /* get data from tx queue and send it */
    907       mutex_global_lock();
    908 
    909       p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_port->tx.queue);
    910       if (p_buf != NULL) {
    911         p_port->tx.queue_size -= p_buf->len;
    912 
    913         mutex_global_unlock();
    914 
    915         RFCOMM_TRACE_DEBUG("Sending RFCOMM_DataReq tx.queue_size=%d",
    916                            p_port->tx.queue_size);
    917 
    918         RFCOMM_DataReq(p_port->rfc.p_mcb, p_port->dlci, p_buf);
    919 
    920         events |= PORT_EV_TXCHAR;
    921 
    922         if (p_port->tx.queue_size == 0) {
    923           events |= PORT_EV_TXEMPTY;
    924           break;
    925         }
    926       }
    927       /* queue is empty-- all data sent */
    928       else {
    929         mutex_global_unlock();
    930 
    931         events |= PORT_EV_TXEMPTY;
    932         break;
    933       }
    934     }
    935     /* If we flow controlled user based on the queue size enable data again */
    936     events |= port_flow_control_user(p_port);
    937   }
    938   return (events & p_port->ev_mask);
    939 }
    940 
    941 /*******************************************************************************
    942  *
    943  * Function         port_rfc_closed
    944  *
    945  * Description      This function when RFCOMM side of port is closed
    946  *
    947  ******************************************************************************/
    948 void port_rfc_closed(tPORT* p_port, uint8_t res) {
    949   uint8_t old_signals;
    950   uint32_t events = 0;
    951   tRFC_MCB* p_mcb = p_port->rfc.p_mcb;
    952 
    953   if ((p_port->state == PORT_STATE_OPENING) && (p_port->is_server)) {
    954     /* The servr side has not been informed that connection is up, ignore */
    955     RFCOMM_TRACE_EVENT("port_rfc_closed in OPENING state ignored");
    956 
    957     rfc_port_timer_stop(p_port);
    958     p_port->rfc.state = RFC_STATE_CLOSED;
    959 
    960     if (p_mcb) {
    961       p_mcb->port_inx[p_port->dlci] = 0;
    962 
    963       /* If there are no more ports opened on this MCB release it */
    964       rfc_check_mcb_active(p_mcb);
    965       p_port->rfc.p_mcb = NULL;
    966     }
    967 
    968     /* Need to restore DLCI to listening state
    969      * if the server was on the initiating RFC
    970      */
    971     p_port->dlci &= 0xfe;
    972 
    973     return;
    974   }
    975 
    976   if ((p_port->state != PORT_STATE_CLOSING) &&
    977       (p_port->state != PORT_STATE_CLOSED)) {
    978     p_port->line_status |= LINE_STATUS_FAILED;
    979 
    980     old_signals = p_port->peer_ctrl.modem_signal;
    981 
    982     p_port->peer_ctrl.modem_signal &=
    983         ~(PORT_DTRDSR_ON | PORT_CTSRTS_ON | PORT_DCD_ON);
    984 
    985     events |= port_get_signal_changes(p_port, old_signals,
    986                                       p_port->peer_ctrl.modem_signal);
    987 
    988     if (p_port->ev_mask & PORT_EV_CONNECT_ERR) events |= PORT_EV_CONNECT_ERR;
    989   }
    990   RFCOMM_TRACE_EVENT("port_rfc_closed state:%d sending events:%x",
    991                      p_port->state, events);
    992 
    993   if ((p_port->p_callback != NULL) && events)
    994     p_port->p_callback(events, p_port->inx);
    995 
    996   if (p_port->p_mgmt_callback) p_port->p_mgmt_callback(res, p_port->inx);
    997 
    998   p_port->rfc.state = RFC_STATE_CLOSED;
    999 
   1000   RFCOMM_TRACE_WARNING("%s RFCOMM connection in state %d closed: %s (res: %d)",
   1001                        __func__, p_port->state, PORT_GetResultString(res), res);
   1002 
   1003   port_release_port(p_port);
   1004 }
   1005 
   1006 /*******************************************************************************
   1007  *
   1008  * Function         port_get_credits
   1009  *
   1010  * Description      Set initial values for credits.
   1011  *                  Adjust max number of rx credits based on negotiated MTU.
   1012  *                  Check max allowed num of bytes, max allowed num buffers,
   1013  *                  should be less then 255
   1014  *
   1015  ******************************************************************************/
   1016 void port_get_credits(tPORT* p_port, uint8_t k) {
   1017   p_port->credit_tx = k;
   1018   if (p_port->credit_tx == 0) p_port->tx.peer_fc = true;
   1019 }
   1020