Asterisk.org: Developer Documentation (28 Oct 2009)

Wed Oct 28 15:47:51 2009

## Asterisk developer's documentation

# chan_modem_i4l.c

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    00001 /*
    00002  * Asterisk -- An open source telephony toolkit.
    00003  *
    00004  * Copyright (C) 1999 - 2005, Digium, Inc.
    00005  *
    00006  * Mark Spencer <markster@digium.com>
    00007  *
    00008  * See http://www.asterisk.org for more information about
    00009  * the Asterisk project. Please do not directly contact
    00010  * any of the maintainers of this project for assistance;
    00011  * the project provides a web site, mailing lists and IRC
    00012  * channels for your use.
    00013  *
    00014  * This program is free software, distributed under the terms of
    00015  * the GNU General Public License Version 2. See the LICENSE file
    00016  * at the top of the source tree.
    00017  */
    00018
    00019 /*! \file
    00020  *
    00021  * \brief ISDN4Linux TTY Driver
    00022  *
    00023  * \ingroup channel_drivers
    00024  */
    00025
    00026 #include <stdio.h>
    00027
    00028 #include <string.h>
    00029 #include <stdlib.h>
    00030 #include <errno.h>
    00031 #include <unistd.h>
    00032 #include <sys/ioctl.h>
    00033
    00034 #include "asterisk.h"
    00035
    00036 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 7221 $")
    00037
    00038 #include "asterisk/lock.h"
    00039 #include "asterisk/vmodem.h"
    00040 #include "asterisk/module.h"
    00041 #include "asterisk/frame.h"
    00042 #include "asterisk/logger.h"
    00043 #include "asterisk/options.h"
    00044 #include "asterisk/dsp.h"
    00045 #include "asterisk/callerid.h"
    00046 #include "asterisk/ulaw.h"
    00047 #include "asterisk/pbx.h"
    00048 #include "asterisk/utils.h"
    00049
    00050 #define STATE_COMMAND   0
    00051 #define STATE_VOICE  1
    00052
    00053 static char *breakcmd = "\0x10\0x14\0x10\0x3";
    00054
    00055 static char *desc = "ISDN4Linux Emulated Modem Driver";
    00056
    00057 static int usecnt;
    00058 AST_MUTEX_DEFINE_STATIC(usecnt_lock);
    00059
    00060 static char *i4l_idents[] = {
    00061    /* Identify ISDN4Linux Driver */
    00062    "Linux ISDN",
    00063    NULL
    00064 };
    00065
    00066 static int i4l_setdev(struct ast_modem_pvt *p, int dev)
    00067 {
    00068    char cmd[80];
    00069    if ((dev != MODEM_DEV_TELCO) && (dev != MODEM_DEV_TELCO_SPK)) {
    00070       ast_log(LOG_WARNING, "ISDN4Linux only supports telco device, not %d.\n", dev);
    00071       return -1;
    00072    } else   /* Convert DEV to our understanding of it */
    00073       dev = 2;
    00074    if (ast_modem_send(p, "AT+VLS?", 0)) {
    00075       ast_log(LOG_WARNING, "Unable to select current mode %d\n", dev);
    00076       return -1;
    00077    }
    00078    if (ast_modem_read_response(p, 5)) {
    00079       ast_log(LOG_WARNING, "Unable to select device %d\n", dev);
    00080       return -1;
    00081    }
    00082    ast_modem_trim(p->response);
    00083    strncpy(cmd, p->response, sizeof(cmd)-1);
    00084    if (ast_modem_expect(p, "OK", 5)) {
    00085       ast_log(LOG_WARNING, "Modem did not respond properly\n");
    00086       return -1;
    00087    }
    00088    if (dev == atoi(cmd)) {
    00089       /* We're already in the right mode, don't bother changing for fear of
    00090          hanging up */
    00091       return 0;
    00092    }
    00093    snprintf(cmd, sizeof(cmd), "AT+VLS=%d", dev);
    00094    if (ast_modem_send(p, cmd, 0))  {
    00095       ast_log(LOG_WARNING, "Unable to select device %d\n", dev);
    00096       return -1;
    00097    }
    00098    if (ast_modem_read_response(p, 5)) {
    00099       ast_log(LOG_WARNING, "Unable to select device %d\n", dev);
    00100       return -1;
    00101    }
    00102    ast_modem_trim(p->response);
    00103    if (strcasecmp(p->response, "VCON") && strcasecmp(p->response, "OK")) {
    00104       ast_log(LOG_WARNING, "Unexpected reply: %s\n", p->response);
    00105       return -1;
    00106    }
    00107    return 0;
    00108 }
    00109
    00110 static int i4l_startrec(struct ast_modem_pvt *p)
    00111 {
    00112    if (ast_modem_send(p, "AT+VRX+VTX", 0) ||
    00113         ast_modem_expect(p, "CONNECT", 5)) {
    00114       ast_log(LOG_WARNING, "Unable to start recording\n");
    00115       return -1;
    00116    }
    00117    p->ministate = STATE_VOICE;
    00118
    00119    /*  let ast dsp detect dtmf */
    00120    if (p->dtmfmode & MODEM_DTMF_AST) {
    00121       if (p->dsp) {
    00122          ast_log(LOG_DEBUG, "Already have a dsp on %s?\n", p->dev);
    00123       } else {
    00124          p->dsp = ast_dsp_new();
    00125          if (p->dsp) {
    00126             ast_log(LOG_DEBUG, "Detecting DTMF inband with sw DSP on %s\n",p->dev);
    00127             ast_dsp_set_features(p->dsp, DSP_FEATURE_DTMF_DETECT|DSP_FEATURE_FAX_DETECT);
    00128             ast_dsp_digitmode(p->dsp, DSP_DIGITMODE_DTMF | 0);
    00129          }
    00130       }
    00131    }
    00132
    00133    return 0;
    00134 }
    00135
    00136 static int i4l_break(struct ast_modem_pvt *p)
    00137 {
    00138    if (ast_modem_send(p, breakcmd, 2)) {
    00139       ast_log(LOG_WARNING, "Failed to break\n");
    00140       return -1;
    00141    }
    00142    if (ast_modem_send(p, "\r\n", 2)) {
    00143       ast_log(LOG_WARNING, "Failed to send enter?\n");
    00144       return -1;
    00145    }
    00146 #if 0
    00147    /* Read any outstanding junk */
    00148    while(!ast_modem_read_response(p, 1));
    00149 #endif
    00150    if (ast_modem_send(p, "AT", 0)) {
    00151       /* Modem might be stuck in some weird mode, try to get it out */
    00152       ast_modem_send(p, "+++", 3);
    00153       if (ast_modem_expect(p, "OK", 10)) {
    00154          ast_log(LOG_WARNING, "Modem is not responding\n");
    00155          return -1;
    00156       }
    00157       if (ast_modem_send(p, "AT", 0)) {
    00158          ast_log(LOG_WARNING, "Modem is not responding\n");
    00159          return -1;
    00160       }
    00161    }
    00162    if (ast_modem_expect(p, "OK", 5)) {
    00163       ast_log(LOG_WARNING, "Modem did not respond properly\n");
    00164       return -1;
    00165    }
    00166    return 0;
    00167 }
    00168
    00169 static int i4l_init(struct ast_modem_pvt *p)
    00170 {
    00171    char cmd[256];
    00172    if (option_debug)
    00173       ast_log(LOG_DEBUG, "i4l_init()\n");
    00174    if (i4l_break(p))
    00175       return -1;
    00176    /* Force into command mode */
    00177    p->ministate = STATE_COMMAND;
    00178    if (ast_modem_send(p, "AT+FCLASS=8", 0) ||
    00179         ast_modem_expect(p, "OK", 5)) {
    00180       ast_log(LOG_WARNING, "Unable to set to voice mode\n");
    00181       return -1;
    00182    }
    00183    if (!ast_strlen_zero(p->msn)) {
    00184       snprintf(cmd, sizeof(cmd), "AT&E%s", p->msn);
    00185       if (ast_modem_send(p, cmd, 0) ||
    00186           ast_modem_expect(p, "OK", 5)) {
    00187          ast_log(LOG_WARNING, "Unable to set MSN to %s\n", p->msn);
    00188          return -1;
    00189       }
    00190    }
    00191    if (!ast_strlen_zero(p->incomingmsn)) {
    00192       char *q;
    00193       snprintf(cmd, sizeof(cmd), "AT&L%s", p->incomingmsn);
    00194       /* translate , into ; since that is the seperator I4L uses, but can't be directly */
    00195       /* put in the config file because it will interpret the rest of the line as comment. */
    00196       q = cmd+4;
    00197       while (*q) {
    00198          if (*q == ',') *q = ';';
    00199          ++q;
    00200       }
    00201       if (ast_modem_send(p, cmd, 0) ||
    00202           ast_modem_expect(p, "OK", 5)) {
    00203          ast_log(LOG_WARNING, "Unable to set Listen to %s\n", p->msn);
    00204          return -1;
    00205       }
    00206    }
    00207    if (ast_modem_send(p, "AT&D2", 0) ||
    00208         ast_modem_expect(p, "OK", 5)) {
    00209       ast_log(LOG_WARNING, "Unable to set to DTR disconnect mode\n");
    00210       return -1;
    00211    }
    00212    if (ast_modem_send(p, "ATS18=1", 0) ||
    00213         ast_modem_expect(p, "OK", 5)) {
    00214       ast_log(LOG_WARNING, "Unable to set to audio only mode\n");
    00215       return -1;
    00216    }
    00217    if (ast_modem_send(p, "ATS13.6=1", 0) ||
    00218         ast_modem_expect(p, "OK", 5)) {
    00219       ast_log(LOG_WARNING, "Unable to set to RUNG indication\n");
    00220       return -1;
    00221    }
    00222    if (ast_modem_send(p, "ATS14=4", 0) ||
    00223         ast_modem_expect(p, "OK", 5)) {
    00224       ast_log(LOG_WARNING, "Unable to set to transparent mode\n");
    00225       return -1;
    00226    }
    00227    if (ast_modem_send(p, "ATS23=9", 0) ||
    00228         ast_modem_expect(p, "OK", 5)) {
    00229       ast_log(LOG_WARNING, "Unable to set to transparent/ringing mode\n");
    00230       return -1;
    00231    }
    00232
    00233    if (ast_modem_send(p, "AT+VSM=6", 0) ||
    00234         ast_modem_expect(p, "OK", 5)) {
    00235       ast_log(LOG_WARNING, "Unable to set to muLAW mode\n");
    00236       return -1;
    00237    }
    00238    if (ast_modem_send(p, "AT+VLS=2", 0) ||
    00239         ast_modem_expect(p, "OK", 5)) {
    00240       ast_log(LOG_WARNING, "Unable to set to phone line interface\n");
    00241       return -1;
    00242    }
    00243    p->escape = 0;
    00244    return 0;
    00245 }
    00246
    00247 static struct ast_frame *i4l_handle_escape(struct ast_modem_pvt *p, char esc)
    00248 {
    00249    /* Handle escaped characters -- but sometimes we call it directly as
    00250       a quick way to cause known responses */
    00251    p->fr.frametype = AST_FRAME_NULL;
    00252    p->fr.subclass = 0;
    00253    p->fr.data = NULL;
    00254    p->fr.datalen = 0;
    00255    p->fr.samples = 0;
    00256    p->fr.offset = 0;
    00257    p->fr.mallocd = 0;
    00258    p->fr.delivery.tv_sec = 0;
    00259    p->fr.delivery.tv_usec = 0;
    00260    if (esc && option_debug)
    00261       ast_log(LOG_DEBUG, "Escaped character '%c'\n", esc);
    00262
    00263    switch(esc) {
    00264    case 'R': /* Pseudo ring */
    00265       p->fr.frametype = AST_FRAME_CONTROL;
    00266       p->fr.subclass = AST_CONTROL_RING;
    00267       return &p->fr;
    00268    case 'I': /* Pseudo ringing */
    00269       p->fr.frametype = AST_FRAME_CONTROL;
    00270       p->fr.subclass =  AST_CONTROL_RINGING;
    00271       return &p->fr;
    00272    case 'X': /* Pseudo connect */
    00273       p->fr.frametype = AST_FRAME_CONTROL;
    00274       p->fr.subclass = AST_CONTROL_ANSWER;
    00275       if (p->owner)
    00276          ast_setstate(p->owner, AST_STATE_UP);
    00277       if (i4l_startrec(p))
    00278          return   NULL;
    00279       return &p->fr;
    00280    case 'b': /* Busy signal */
    00281       p->fr.frametype = AST_FRAME_CONTROL;
    00282       p->fr.subclass = AST_CONTROL_BUSY;
    00283       return &p->fr;
    00284    case 'o': /* Overrun */
    00285       ast_log(LOG_WARNING, "Overflow on modem, flushing buffers\n");
    00286       if (ast_modem_send(p, "\0x10E", 2))
    00287          ast_log(LOG_WARNING, "Unable to flush buffers\n");
    00288       return &p->fr;
    00289    case CHAR_ETX: /* End Transmission */
    00290       return NULL;
    00291    case 'u': /* Underrun */
    00292       ast_log(LOG_WARNING, "Data underrun\n");
    00293       /* Fall Through */
    00294    case 'd': /* Dialtone */
    00295    case 'c': /* Calling Tone */
    00296    case 'e': /* European version */
    00297    case 'a': /* Answer Tone */
    00298    case 'f': /* Bell Answer Tone */
    00299    case 'T': /* Timing mark */
    00300    case 't': /* Handset off hook */
    00301    case 'h': /* Handset hungup */
    00302       /* Ignore */
    00303       if (option_debug)
    00304          ast_log(LOG_DEBUG, "Ignoring Escaped character '%c' (%d)\n", esc, esc);
    00305       return &p->fr;
    00306    case '0':
    00307    case '1':
    00308    case '2':
    00309    case '3':
    00310    case '4':
    00311    case '5':
    00312    case '6':
    00313    case '7':
    00314    case '8':
    00315    case '9':
    00316    case '*':
    00317    case '#':
    00318       ast_log(LOG_DEBUG, "Detected outband DTMF digit: '%c' (%d)\n", esc, esc);
    00319       p->fr.frametype=AST_FRAME_DTMF;
    00320       p->fr.subclass=esc;
    00321       return &p->fr;
    00322    case 0: /* Pseudo signal */
    00323       return &p->fr;
    00324    default:
    00325       ast_log(LOG_DEBUG, "Unknown Escaped character '%c' (%d)\n", esc, esc);
    00326    }
    00327    return &p->fr;
    00328 }
    00329
    00330 static struct ast_frame *i4l_read(struct ast_modem_pvt *p)
    00331 {
    00332    unsigned char result[256];
    00333    short *b;
    00334    struct ast_frame *f=NULL;
    00335    int res;
    00336    int x;
    00337    if (p->ministate == STATE_COMMAND) {
    00338       /* Read the first two bytes, first, in case it's a control message */
    00339       res = read(p->fd, result, 2);
    00340       if (res < 2) {
    00341          /* short read, means there was a hangup? */
    00342          /* (or is this also possible without hangup?) */
    00343          /* Anyway, reading from unitialized buffers is a bad idea anytime. */
    00344          if (errno == EAGAIN)
    00345             return i4l_handle_escape(p, 0);
    00346          return NULL;
    00347       }
    00348       if (result[0] == CHAR_DLE) {
    00349          return i4l_handle_escape(p, result[1]);
    00350
    00351       } else {
    00352          if ((result[0] == '\n') || (result[0] == '\r'))
    00353             return i4l_handle_escape(p, 0);
    00354          /* Read the rest of the line */
    00355          fgets(result + 2, sizeof(result) - 2, p->f);
    00356          ast_modem_trim(result);
    00357          if (!strcasecmp(result, "VCON")) {
    00358             /* If we're in immediate mode, reply now */
    00359 /*          if (p->mode == MODEM_MODE_IMMEDIATE) */
    00360                return i4l_handle_escape(p, 'X');
    00361          } else
    00362          if (!strcasecmp(result, "BUSY")) {
    00363             /* Same as a busy signal */
    00364             return i4l_handle_escape(p, 'b');
    00365          } else
    00366          if (!strncasecmp(result, "CALLER NUMBER: ", 15 )) {
    00367             strncpy(p->cid_num, result + 15, sizeof(p->cid_num)-1);
    00368             return i4l_handle_escape(p, 0);
    00369          } else
    00370          if (!strcasecmp(result, "RINGING")) {
    00371             if (option_verbose > 2)
    00372                ast_verbose(VERBOSE_PREFIX_3 "%s is ringing...\n", p->dev);
    00373             return i4l_handle_escape(p, 'I');
    00374          } else
    00375          if (!strncasecmp(result, "RUNG", 4)) {
    00376             /* PM2002: the line was hung up before we picked it up, bye bye */
    00377             if (option_verbose > 2)
    00378                ast_verbose(VERBOSE_PREFIX_3 "%s was hung up on before we answered\n", p->dev);
    00379             return NULL;
    00380          } else
    00381          if (!strncasecmp(result, "RING", 4)) {
    00382             if (result[4]=='/')
    00383                strncpy(p->dnid, result + 5, sizeof(p->dnid)-1);
    00384             return i4l_handle_escape(p, 'R');
    00385          } else
    00386          if (!strcasecmp(result, "NO CARRIER")) {
    00387             if (option_verbose > 2)
    00388                ast_verbose(VERBOSE_PREFIX_3 "%s hung up on\n", p->dev);
    00389             return NULL;
    00390          } else
    00391          if (!strcasecmp(result, "NO DIALTONE")) {
    00392             /* There's no dialtone, so the line isn't working */
    00393             ast_log(LOG_WARNING, "Device '%s' lacking dialtone\n", p->dev);
    00394             return NULL;
    00395          }
    00396          if (option_debug)
    00397             ast_log(LOG_DEBUG, "Modem said '%s'\n", result);
    00398          return i4l_handle_escape(p, 0);
    00399       }
    00400    } else {
    00401       /* We have to be more efficient in voice mode */
    00402       b = (short *)(p->obuf + p->obuflen);
    00403       while (p->obuflen/2 < 240) {
    00404          /* Read ahead the full amount */
    00405          res = read(p->fd, result, 240 - p->obuflen/2);
    00406          if (res < 1) {
    00407             /* If there's nothing there, just continue on */
    00408             if (errno == EAGAIN)
    00409                return i4l_handle_escape(p, 0);
    00410             ast_log(LOG_WARNING, "Read failed: %s\n", strerror(errno));
    00411             return NULL;
    00412          }
    00413
    00414          for (x=0;x<res;x++) {
    00415             /* Process all the bytes that we've read */
    00416             switch(result[x]) {
    00417             case CHAR_DLE:
    00418 #if 0
    00419                ast_log(LOG_DEBUG, "Ooh, an escape at %d...\n", x);
    00420 #endif
    00421                if (!p->escape) {
    00422                   /* Note that next value is
    00423                      an escape, and continue. */
    00424                   p->escape++;
    00425                   break;
    00426                } else {
    00427                   /* Send as is -- fallthrough */
    00428                   p->escape = 0;
    00429                }
    00430             default:
    00431                if (p->escape) {
    00432                   ast_log(LOG_DEBUG, "Value of escape is %c (%d)...\n", result[x] < 32 ? '^' : result[x], result[x]);
    00433                   p->escape = 0;
    00434                   if (f)
    00435                      ast_log(LOG_WARNING, "Warning: Dropped a signal frame\n");
    00436                   f = i4l_handle_escape(p, result[x]);
    00437                   /* If i4l_handle_escape says NULL, say it now, doesn't matter
    00438                   what else is there, the connection is dead. */
    00439                   if (!f)
    00440                      return NULL;
    00441                } else {
    00442                   *(b++) = AST_MULAW((int)result[x]);
    00443                   p->obuflen += 2;
    00444                }
    00445             }
    00446          }
    00447          if (f)
    00448             break;
    00449       }
    00450       if (f) {
    00451          if( ! (!(p->dtmfmode & MODEM_DTMF_I4L) && f->frametype == AST_FRAME_DTMF))
    00452          return f;
    00453       }
    00454
    00455       /* If we get here, we have a complete voice frame */
    00456       p->fr.frametype = AST_FRAME_VOICE;
    00457       p->fr.subclass = AST_FORMAT_SLINEAR;
    00458       p->fr.samples = 240;
    00459       p->fr.data = p->obuf;
    00460       p->fr.datalen = p->obuflen;
    00461       p->fr.mallocd = 0;
    00462       p->fr.delivery.tv_sec = 0;
    00463       p->fr.delivery.tv_usec = 0;
    00464       p->fr.offset = AST_FRIENDLY_OFFSET;
    00465       p->fr.src = __FUNCTION__;
    00466       p->obuflen = 0;
    00467
    00468       /* process with dsp */
    00469       if (p->dsp) {
    00470          f = ast_dsp_process(p->owner, p->dsp, &p->fr);
    00471          if (f && (f->frametype == AST_FRAME_DTMF)) {
    00472             ast_log(LOG_DEBUG, "Detected inband DTMF digit: %c on %s\n", f->subclass, p->dev);
    00473             if (f->subclass == 'f') {
    00474                /* Fax tone -- Handle and return NULL */
    00475                struct ast_channel *ast = p->owner;
    00476                if (!p->faxhandled) {
    00477                   p->faxhandled++;
    00478                   if (strcmp(ast->exten, "fax")) {
    00479                      const char *target_context = ast_strlen_zero(ast->macrocontext) ? ast->context : ast->macrocontext;
    00480
    00481                      if (ast_exists_extension(ast, target_context, "fax", 1, ast->cid.cid_num)) {
    00482                         if (option_verbose > 2)
    00483                            ast_verbose(VERBOSE_PREFIX_3 "Redirecting %s to fax extension\n", ast->name);
    00484                         /* Save the DID/DNIS when we transfer the fax call to a "fax" extension */
    00485                         pbx_builtin_setvar_helper(ast, "FAXEXTEN", ast->exten);
    00486                         if (ast_async_goto(ast, target_context, "fax", 1))
    00487                            ast_log(LOG_WARNING, "Failed to async goto '%s' into fax of '%s'\n", ast->name, target_context);
    00488                      } else
    00489                         ast_log(LOG_NOTICE, "Fax detected, but no fax extension\n");
    00490                   } else
    00491                      ast_log(LOG_DEBUG, "Already in a fax extension, not redirecting\n");
    00492                } else
    00493                   ast_log(LOG_DEBUG, "Fax already handled\n");
    00494                p->fr.frametype = AST_FRAME_NULL;
    00495                p->fr.subclass = 0;
    00496                f = &p->fr;
    00497             }
    00498             return f;
    00499          }
    00500       }
    00501
    00502       return &p->fr;
    00503    }
    00504    return NULL;
    00505 }
    00506
    00507 static int i4l_write(struct ast_modem_pvt *p, struct ast_frame *f)
    00508 {
    00509 #define MAX_WRITE_SIZE 2048
    00510    unsigned char result[MAX_WRITE_SIZE << 1];
    00511    unsigned char b;
    00512    int bpos=0, x;
    00513    int res;
    00514    if (f->datalen > MAX_WRITE_SIZE) {
    00515       ast_log(LOG_WARNING, "Discarding too big frame of size %d\n", f->datalen);
    00516       return -1;
    00517    }
    00518    if (f->frametype != AST_FRAME_VOICE) {
    00519       ast_log(LOG_WARNING, "Don't know how to handle %d type frames\n", f->frametype);
    00520       return -1;
    00521    }
    00522    if (f->subclass != AST_FORMAT_SLINEAR) {
    00523       ast_log(LOG_WARNING, "Don't know how to handle anything but signed linear frames\n");
    00524       return -1;
    00525    }
    00526    for (x=0;x<f->datalen/2;x++) {
    00527       b = AST_LIN2MU(((short *)f->data)[x]);
    00528       result[bpos++] = b;
    00529       if (b == CHAR_DLE)
    00530          result[bpos++]=b;
    00531    }
    00532 #if 0
    00533    res = fwrite(result, bpos, 1, p->f);
    00534    res *= bpos;
    00535 #else
    00536    res = write(p->fd, result, bpos);
    00537 #endif
    00538    if (res < 1) {
    00539       if (errno != EAGAIN) {
    00540          ast_log(LOG_WARNING, "Failed to write buffer\n");
    00541          return -1;
    00542       }
    00543    }
    00544 #if 0
    00545    printf("Result of write is %d\n", res);
    00546 #endif
    00547    return 0;
    00548 }
    00549
    00550 static char *i4l_identify(struct ast_modem_pvt *p)
    00551 {
    00552    return strdup("Linux ISDN");
    00553 }
    00554
    00555 static void i4l_incusecnt(void)
    00556 {
    00557    ast_mutex_lock(&usecnt_lock);
    00558    usecnt++;
    00559    ast_mutex_unlock(&usecnt_lock);
    00560    ast_update_use_count();
    00561 }
    00562
    00563 static void i4l_decusecnt(void)
    00564 {
    00565    ast_mutex_lock(&usecnt_lock);
    00566    usecnt++;
    00567    ast_mutex_unlock(&usecnt_lock);
    00568    ast_update_use_count();
    00569 }
    00570
    00571 static int i4l_answer(struct ast_modem_pvt *p)
    00572 {
    00573    if (ast_modem_send(p, "ATA\r", 4) ||
    00574         ast_modem_expect(p, "VCON", 10)) {
    00575       ast_log(LOG_WARNING, "Unable to answer: %s", p->response);
    00576       return -1;
    00577    }
    00578 #if 1
    00579    if (ast_modem_send(p, "AT+VDD=0,8", 0) ||
    00580         ast_modem_expect(p, "OK", 5)) {
    00581       ast_log(LOG_WARNING, "Unable to set to phone line interface\n");
    00582       return -1;
    00583    }
    00584 #endif
    00585    if (ast_modem_send(p, "AT+VTX+VRX", 0) ||
    00586         ast_modem_expect(p, "CONNECT", 10)) {
    00587       ast_log(LOG_WARNING, "Unable to answer: %s", p->response);
    00588       return -1;
    00589    }
    00590    p->ministate = STATE_VOICE;
    00591
    00592    /*  let ast dsp detect dtmf */
    00593    if (p->dtmfmode & MODEM_DTMF_AST) {
    00594       if (p->dsp) {
    00595          ast_log(LOG_DEBUG, "Already have a dsp on %s?\n", p->dev);
    00596       } else {
    00597          p->dsp = ast_dsp_new();
    00598          if (p->dsp) {
    00599             ast_log(LOG_DEBUG, "Detecting DTMF inband with sw DSP on %s\n",p->dev);
    00600             ast_dsp_set_features(p->dsp, DSP_FEATURE_DTMF_DETECT|DSP_FEATURE_FAX_DETECT);
    00601             ast_dsp_digitmode(p->dsp, DSP_DIGITMODE_DTMF | 0);
    00602          }
    00603       }
    00604    }
    00605
    00606    return 0;
    00607 }
    00608
    00609 static int i4l_dialdigit(struct ast_modem_pvt *p, char digit)
    00610 {
    00611    char c[2];
    00612    if (p->ministate == STATE_VOICE) {
    00613       if (p->dtmfmodegen & MODEM_DTMF_I4L) {
    00614       c[0] = CHAR_DLE;
    00615       c[1] = digit;
    00616       write(p->fd, c, 2);
    00617          ast_log(LOG_DEBUG, "Send ISDN out-of-band DTMF %c\n",digit);
    00618       }
    00619       if(p->dtmfmodegen & MODEM_DTMF_AST) {
    00620          ast_log(LOG_DEBUG, "Generating inband DTMF\n");
    00621          return -1;
    00622       }
    00623    } else
    00624       ast_log(LOG_DEBUG, "Asked to send digit but call not up on %s\n", p->dev);
    00625    return 0;
    00626 }
    00627
    00628 static int i4l_dial(struct ast_modem_pvt *p, char *stuff)
    00629 {
    00630    char cmd[80];
    00631    char tmpmsn[255];
    00632    struct ast_channel *c = p->owner;
    00633
    00634    /* Find callerid number first, to set the correct A number */
    00635    if (c && c->cid.cid_num && !(c->cid.cid_pres & 0x20)) {
    00636        snprintf(tmpmsn, sizeof(tmpmsn), ",%s,", c->cid.cid_num);
    00637        if(!ast_strlen_zero(p->outgoingmsn) && strstr(p->outgoingmsn,tmpmsn) != NULL) {
    00638          /* Tell ISDN4Linux to use this as A number */
    00639          snprintf(cmd, sizeof(cmd), "AT&E%s\n", c->cid.cid_num);
    00640          if (ast_modem_send(p, cmd, strlen(cmd))) {
    00641       ast_log(LOG_WARNING, "Unable to set A number to %s\n", c->cid.cid_num);
    00642          }
    00643
    00644        } else {
    00645          ast_log(LOG_WARNING, "Outgoing MSN %s not allowed (see outgoingmsn=%s in modem.conf)\n",c->cid.cid_num,p->outgoingmsn);
    00646        }
    00647    }
    00648
    00649    snprintf(cmd, sizeof(cmd), "ATD%c %s\n", p->dialtype,stuff);
    00650    if (ast_modem_send(p, cmd, strlen(cmd))) {
    00651       ast_log(LOG_WARNING, "Unable to dial\n");
    00652       return -1;
    00653    }
    00654    return 0;
    00655 }
    00656
    00657 static int i4l_hangup(struct ast_modem_pvt *p)
    00658 {
    00659    char dummy[50];
    00660    int dtr = TIOCM_DTR;
    00661
    00662    /* free the memory used by the DSP */
    00663    if (p->dsp) {
    00664       ast_dsp_free(p->dsp);
    00665       p->dsp = NULL;
    00666    }
    00667
    00668    /* down DTR to hangup modem */
    00669    ioctl(p->fd, TIOCMBIC, &dtr);
    00670    /* Read anything outstanding */
    00671    while(read(p->fd, dummy, sizeof(dummy)) > 0);
    00672
    00673    /* rise DTR to re-enable line */
    00674    ioctl(p->fd, TIOCMBIS, &dtr);
    00675
    00676    /* Read anything outstanding */
    00677    while(read(p->fd, dummy, sizeof(dummy)) > 0);
    00678
    00679    /* basically we're done, just to be sure */
    00680    write(p->fd, "\n\n", 2);
    00681    read(p->fd, dummy, sizeof(dummy));
    00682    if (ast_modem_send(p, "ATH", 0)) {
    00683       ast_log(LOG_WARNING, "Unable to hang up\n");
    00684       return -1;
    00685    }
    00686    if (ast_modem_expect(p, "OK", 5)) {
    00687       ast_log(LOG_WARNING, "Final 'OK' not received\n");
    00688       return -1;
    00689    }
    00690
    00691    return 0;
    00692 }
    00693
    00694 static struct ast_modem_driver i4l_driver =
    00695 {
    00696    "i4l",
    00697    i4l_idents,
    00698    AST_FORMAT_SLINEAR,
    00699    0,    /* Not full duplex */
    00700    i4l_incusecnt, /* incusecnt */
    00701    i4l_decusecnt, /* decusecnt */
    00702    i4l_identify,  /* identify */
    00703    i4l_init,   /* init */
    00704    i4l_setdev, /* setdev */
    00705    i4l_read,
    00706    i4l_write,
    00707    i4l_dial,   /* dial */
    00708    i4l_answer, /* answer */
    00709    i4l_hangup, /* hangup */
    00710    i4l_startrec,  /* start record */
    00711    NULL, /* stop record */
    00712    NULL, /* start playback */
    00713    NULL, /* stop playback */
    00714    NULL, /* set silence supression */
    00715    i4l_dialdigit, /* dialdigit */
    00716 };
    00717
    00718
    00719
    00720 int usecount(void)
    00721 {
    00722    return usecnt;
    00723 }
    00724
    00725 int load_module(void)
    00726 {
    00727    return ast_register_modem_driver(&i4l_driver);
    00728 }
    00729
    00730 int unload_module(void)
    00731 {
    00732    return ast_unregister_modem_driver(&i4l_driver);
    00733 }
    00734
    00735 char *description()
    00736 {
    00737    return desc;
    00738 }
    00739
    00740 char *key()
    00741 {
    00742    return ASTERISK_GPL_KEY;
    00743 }