git.oblomov.eu Git - linux-2.6/blob - drivers/isdn/i4l/isdn_v110.c

   1 /* $Id: isdn_v110.c,v 1.1.2.2 2004/01/12 22:37:19 keil Exp $
   2  *
   3  * Linux ISDN subsystem, V.110 related functions (linklevel).
   4  *
   5  * Copyright by Thomas Pfeiffer (pfeiffer@pds.de)
   6  *
   7  * This software may be used and distributed according to the terms
   8  * of the GNU General Public License, incorporated herein by reference.
   9  *
  10  */
  11
  12 #include <linux/string.h>
  13 #include <linux/kernel.h>
  14 #include <linux/slab.h>
  15 #include <linux/mm.h>
  16 #include <linux/delay.h>
  17
  18 #include <linux/isdn.h>
  19 #include "isdn_v110.h"
  20
  21 #undef ISDN_V110_DEBUG
  22
  23 char *isdn_v110_revision = "$Revision: 1.1.2.2 $";
  24
  25 #define V110_38400 255
  26 #define V110_19200  15
  27 #define V110_9600    3
  28
  29 /*
  30  * The following data are precoded matrices, online and offline matrix
  31  * for 9600, 19200 und 38400, respectively
  32  */
  33 static unsigned char V110_OnMatrix_9600[] =
  34 {0xfc, 0xfc, 0xfc, 0xfc, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff,
  35  0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd,
  36  0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff,
  37  0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xfd};
  38
  39 static unsigned char V110_OffMatrix_9600[] =
  40 {0xfc, 0xfc, 0xfc, 0xfc, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  41  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  42  0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  43  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  44
  45 static unsigned char V110_OnMatrix_19200[] =
  46 {0xf0, 0xf0, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7,
  47  0xfd, 0xff, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7, 0xff, 0xf7};
  48
  49 static unsigned char V110_OffMatrix_19200[] =
  50 {0xf0, 0xf0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  51  0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
  52
  53 static unsigned char V110_OnMatrix_38400[] =
  54 {0x00, 0x7f, 0x7f, 0x7f, 0x7f, 0xfd, 0x7f, 0x7f, 0x7f, 0x7f};
  55
  56 static unsigned char V110_OffMatrix_38400[] =
  57 {0x00, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff, 0xff, 0xff};
  58
  59 /*
  60  * FlipBits reorders sequences of keylen bits in one byte.
  61  * E.g. source order 7654321 will be converted to 45670123 when keylen = 4,
  62  * and to 67452301 when keylen = 2. This is necessary because ordering on
  63  * the isdn line is the other way.
  64  */
  65 static inline unsigned char
  66 FlipBits(unsigned char c, int keylen)
  67 {
  68         unsigned char b = c;
  69         unsigned char bit = 128;
  70         int i;
  71         int j;
  72         int hunks = (8 / keylen);
  73
  74         c = 0;
  75         for (i = 0; i < hunks; i++) {
  76                 for (j = 0; j < keylen; j++) {
  77                         if (b & (bit >> j))
  78                                 c |= bit >> (keylen - j - 1);
  79                 }
  80                 bit >>= keylen;
  81         }
  82         return c;
  83 }
  84
  85
  86 /* isdn_v110_open allocates and initializes private V.110 data
  87  * structures and returns a pointer to these.
  88  */
  89 static isdn_v110_stream *
  90 isdn_v110_open(unsigned char key, int hdrlen, int maxsize)
  91 {
  92         int i;
  93         isdn_v110_stream *v;
  94
  95         if ((v = kzalloc(sizeof(isdn_v110_stream), GFP_ATOMIC)) == NULL)
  96                 return NULL;
  97         v->key = key;
  98         v->nbits = 0;
  99         for (i = 0; key & (1 << i); i++)
 100                 v->nbits++;
 101
 102         v->nbytes = 8 / v->nbits;
 103         v->decodelen = 0;
 104
 105         switch (key) {
 106                 case V110_38400:
 107                         v->OnlineFrame = V110_OnMatrix_38400;
 108                         v->OfflineFrame = V110_OffMatrix_38400;
 109                         break;
 110                 case V110_19200:
 111                         v->OnlineFrame = V110_OnMatrix_19200;
 112                         v->OfflineFrame = V110_OffMatrix_19200;
 113                         break;
 114                 default:
 115                         v->OnlineFrame = V110_OnMatrix_9600;
 116                         v->OfflineFrame = V110_OffMatrix_9600;
 117                         break;
 118         }
 119         v->framelen = v->nbytes * 10;
 120         v->SyncInit = 5;
 121         v->introducer = 0;
 122         v->dbit = 1;
 123         v->b = 0;
 124         v->skbres = hdrlen;
 125         v->maxsize = maxsize - hdrlen;
 126         if ((v->encodebuf = kmalloc(maxsize, GFP_ATOMIC)) == NULL) {
 127                 kfree(v);
 128                 return NULL;
 129         }
 130         return v;
 131 }
 132
 133 /* isdn_v110_close frees private V.110 data structures */
 134 void
 135 isdn_v110_close(isdn_v110_stream * v)
 136 {
 137         if (v == NULL)
 138                 return;
 139 #ifdef ISDN_V110_DEBUG
 140         printk(KERN_DEBUG "v110 close\n");
 141 #endif
 142         kfree(v->encodebuf);
 143         kfree(v);
 144 }
 145
 146
 147 /*
 148  * ValidHeaderBytes return the number of valid bytes in v->decodebuf
 149  */
 150 static int
 151 ValidHeaderBytes(isdn_v110_stream * v)
 152 {
 153         int i;
 154         for (i = 0; (i < v->decodelen) && (i < v->nbytes); i++)
 155                 if ((v->decodebuf[i] & v->key) != 0)
 156                         break;
 157         return i;
 158 }
 159
 160 /*
 161  * SyncHeader moves the decodebuf ptr to the next valid header
 162  */
 163 static void
 164 SyncHeader(isdn_v110_stream * v)
 165 {
 166         unsigned char *rbuf = v->decodebuf;
 167         int len = v->decodelen;
 168
 169         if (len == 0)
 170                 return;
 171         for (rbuf++, len--; len > 0; len--, rbuf++)     /* such den SyncHeader in buf ! */
 172                 if ((*rbuf & v->key) == 0)      /* erstes byte gefunden ?       */
 173                         break;  /* jupp!                        */
 174         if (len)
 175                 memcpy(v->decodebuf, rbuf, len);
 176
 177         v->decodelen = len;
 178 #ifdef ISDN_V110_DEBUG
 179         printk(KERN_DEBUG "isdn_v110: Header resync\n");
 180 #endif
 181 }
 182
 183 /* DecodeMatrix takes n (n>=1) matrices (v110 frames, 10 bytes) where
 184    len is the number of matrix-lines. len must be a multiple of 10, i.e.
 185    only complete matices must be given.
 186    From these, netto data is extracted and returned in buf. The return-value
 187    is the bytecount of the decoded data.
 188  */
 189 static int
 190 DecodeMatrix(isdn_v110_stream * v, unsigned char *m, int len, unsigned char *buf)
 191 {
 192         int line = 0;
 193         int buflen = 0;
 194         int mbit = 64;
 195         int introducer = v->introducer;
 196         int dbit = v->dbit;
 197         unsigned char b = v->b;
 198
 199         while (line < len) {    /* Are we done with all lines of the matrix? */
 200                 if ((line % 10) == 0) { /* the 0. line of the matrix is always 0 ! */
 201                         if (m[line] != 0x00) {  /* not 0 ? -> error! */
 202 #ifdef ISDN_V110_DEBUG
 203                                 printk(KERN_DEBUG "isdn_v110: DecodeMatrix, V110 Bad Header\n");
 204                                 /* returning now is not the right thing, though :-( */
 205 #endif
 206                         }
 207                         line++; /* next line of matrix */
 208                         continue;
 209                 } else if ((line % 10) == 5) {  /* in line 5 there's only e-bits ! */
 210                         if ((m[line] & 0x70) != 0x30) { /* 011 has to be at the beginning! */
 211 #ifdef ISDN_V110_DEBUG
 212                                 printk(KERN_DEBUG "isdn_v110: DecodeMatrix, V110 Bad 5th line\n");
 213                                 /* returning now is not the right thing, though :-( */
 214 #endif
 215                         }
 216                         line++; /* next line */
 217                         continue;
 218                 } else if (!introducer) {       /* every byte starts with 10 (stopbit, startbit) */
 219                         introducer = (m[line] & mbit) ? 0 : 1;  /* current bit of the matrix */
 220                       next_byte:
 221                         if (mbit > 2) { /* was it the last bit in this line ? */
 222                                 mbit >>= 1;     /* no -> take next */
 223                                 continue;
 224                         }       /* otherwise start with leftmost bit in the next line */
 225                         mbit = 64;
 226                         line++;
 227                         continue;
 228                 } else {        /* otherwise we need to set a data bit */
 229                         if (m[line] & mbit)     /* was that bit set in the matrix ? */
 230                                 b |= dbit;      /* yes -> set it in the data byte */
 231                         else
 232                                 b &= dbit - 1;  /* no -> clear it in the data byte */
 233                         if (dbit < 128) /* is that data byte done ? */
 234                                 dbit <<= 1;     /* no, got the next bit */
 235                         else {  /* data byte is done */
 236                                 buf[buflen++] = b;      /* copy byte into the output buffer */
 237                                 introducer = b = 0;     /* init of the intro sequence and of the data byte */
 238                                 dbit = 1;       /* next we look for the 0th bit */
 239                         }
 240                         goto next_byte; /* look for next bit in the matrix */
 241                 }
 242         }
 243         v->introducer = introducer;
 244         v->dbit = dbit;
 245         v->b = b;
 246         return buflen;          /* return number of bytes in the output buffer */
 247 }
 248
 249 /*
 250  * DecodeStream receives V.110 coded data from the input stream. It recovers the
 251  * original frames.
 252  * The input stream doesn't need to be framed
 253  */
 254 struct sk_buff *
 255 isdn_v110_decode(isdn_v110_stream * v, struct sk_buff *skb)
 256 {
 257         int i;
 258         int j;
 259         int len;
 260         unsigned char *v110_buf;
 261         unsigned char *rbuf;
 262
 263         if (!skb) {
 264                 printk(KERN_WARNING "isdn_v110_decode called with NULL skb!\n");
 265                 return NULL;
 266         }
 267         rbuf = skb->data;
 268         len = skb->len;
 269         if (v == NULL) {
 270                 /* invalid handle, no chance to proceed */
 271                 printk(KERN_WARNING "isdn_v110_decode called with NULL stream!\n");
 272                 dev_kfree_skb(skb);
 273                 return NULL;
 274         }
 275         if (v->decodelen == 0)  /* cache empty?               */
 276                 for (; len > 0; len--, rbuf++)  /* scan for SyncHeader in buf */
 277                         if ((*rbuf & v->key) == 0)
 278                                 break;  /* found first byte           */
 279         if (len == 0) {
 280                 dev_kfree_skb(skb);
 281                 return NULL;
 282         }
 283         /* copy new data to decode-buffer */
 284         memcpy(&(v->decodebuf[v->decodelen]), rbuf, len);
 285         v->decodelen += len;
 286       ReSync:
 287         if (v->decodelen < v->nbytes) { /* got a new header ? */
 288                 dev_kfree_skb(skb);
 289                 return NULL;    /* no, try later      */
 290         }
 291         if (ValidHeaderBytes(v) != v->nbytes) { /* is that a valid header? */
 292                 SyncHeader(v);  /* no -> look for header */
 293                 goto ReSync;
 294         }
 295         len = (v->decodelen - (v->decodelen % (10 * v->nbytes))) / v->nbytes;
 296         if ((v110_buf = kmalloc(len, GFP_ATOMIC)) == NULL) {
 297                 printk(KERN_WARNING "isdn_v110_decode: Couldn't allocate v110_buf\n");
 298                 dev_kfree_skb(skb);
 299                 return NULL;
 300         }
 301         for (i = 0; i < len; i++) {
 302                 v110_buf[i] = 0;
 303                 for (j = 0; j < v->nbytes; j++)
 304                         v110_buf[i] |= (v->decodebuf[(i * v->nbytes) + j] & v->key) << (8 - ((j + 1) * v->nbits));
 305                 v110_buf[i] = FlipBits(v110_buf[i], v->nbits);
 306         }
 307         v->decodelen = (v->decodelen % (10 * v->nbytes));
 308         memcpy(v->decodebuf, &(v->decodebuf[len * v->nbytes]), v->decodelen);
 309
 310         skb_trim(skb, DecodeMatrix(v, v110_buf, len, skb->data));
 311         kfree(v110_buf);
 312         if (skb->len)
 313                 return skb;
 314         else {
 315                 kfree_skb(skb);
 316                 return NULL;
 317         }
 318 }
 319
 320 /* EncodeMatrix takes input data in buf, len is the bytecount.
 321    Data is encoded into v110 frames in m. Return value is the number of
 322    matrix-lines generated.
 323  */
 324 static int
 325 EncodeMatrix(unsigned char *buf, int len, unsigned char *m, int mlen)
 326 {
 327         int line = 0;
 328         int i = 0;
 329         int mbit = 128;
 330         int dbit = 1;
 331         int introducer = 3;
 332         int ibit[] = {0, 1, 1};
 333
 334         while ((i < len) && (line < mlen)) {    /* while we still have input data */
 335                 switch (line % 10) {    /* in which line of the matrix are we? */
 336                         case 0:
 337                                 m[line++] = 0x00;       /* line 0 is always 0 */
 338                                 mbit = 128;     /* go on with the 7th bit */
 339                                 break;
 340                         case 5:
 341                                 m[line++] = 0xbf;       /* line 5 is always 10111111 */
 342                                 mbit = 128;     /* go on with the 7th bit */
 343                                 break;
 344                 }
 345                 if (line >= mlen) {
 346                         printk(KERN_WARNING "isdn_v110 (EncodeMatrix): buffer full!\n");
 347                         return line;
 348                 }
 349         next_bit:
 350                 switch (mbit) { /* leftmost or rightmost bit ? */
 351                         case 1:
 352                                 line++; /* rightmost -> go to next line */
 353                                 if (line >= mlen) {
 354                                         printk(KERN_WARNING "isdn_v110 (EncodeMatrix): buffer full!\n");
 355                                         return line;
 356                                 }
 357                         case 128:
 358                                 m[line] = 128;  /* leftmost -> set byte to 1000000 */
 359                                 mbit = 64;      /* current bit in the matrix line */
 360                                 continue;
 361                 }
 362                 if (introducer) {       /* set 110 sequence ? */
 363                         introducer--;   /* set on digit less */
 364                         m[line] |= ibit[introducer] ? mbit : 0; /* set corresponding bit */
 365                         mbit >>= 1;     /* bit of matrix line  >> 1 */
 366                         goto next_bit;  /* and go on there */
 367                 }               /* else push data bits into the matrix! */
 368                 m[line] |= (buf[i] & dbit) ? mbit : 0;  /* set data bit in matrix */
 369                 if (dbit == 128) {      /* was it the last one? */
 370                         dbit = 1;       /* then go on with first bit of  */
 371                         i++;            /* next byte in input buffer */
 372                         if (i < len)    /* input buffer done ? */
 373                                 introducer = 3; /* no, write introducer 110 */
 374                         else {  /* input buffer done ! */
 375                                 m[line] |= (mbit - 1) & 0xfe;   /* set remaining bits in line to 1 */
 376                                 break;
 377                         }
 378                 } else          /* not the last data bit */
 379                         dbit <<= 1;     /* then go to next data bit */
 380                 mbit >>= 1;     /* go to next bit of matrix */
 381                 goto next_bit;
 382
 383         }
 384         /* if necessary, generate remaining lines of the matrix... */
 385         if ((line) && ((line + 10) < mlen))
 386                 switch (++line % 10) {
 387                         case 1:
 388                                 m[line++] = 0xfe;
 389                         case 2:
 390                                 m[line++] = 0xfe;
 391                         case 3:
 392                                 m[line++] = 0xfe;
 393                         case 4:
 394                                 m[line++] = 0xfe;
 395                         case 5:
 396                                 m[line++] = 0xbf;
 397                         case 6:
 398                                 m[line++] = 0xfe;
 399                         case 7:
 400                                 m[line++] = 0xfe;
 401                         case 8:
 402                                 m[line++] = 0xfe;
 403                         case 9:
 404                                 m[line++] = 0xfe;
 405                 }
 406         return line;            /* that's how many lines we have */
 407 }
 408
 409 /*
 410  * Build a sync frame.
 411  */
 412 static struct sk_buff *
 413 isdn_v110_sync(isdn_v110_stream *v)
 414 {
 415         struct sk_buff *skb;
 416
 417         if (v == NULL) {
 418                 /* invalid handle, no chance to proceed */
 419                 printk(KERN_WARNING "isdn_v110_sync called with NULL stream!\n");
 420                 return NULL;
 421         }
 422         if ((skb = dev_alloc_skb(v->framelen + v->skbres))) {
 423                 skb_reserve(skb, v->skbres);
 424                 memcpy(skb_put(skb, v->framelen), v->OfflineFrame, v->framelen);
 425         }
 426         return skb;
 427 }
 428
 429 /*
 430  * Build an idle frame.
 431  */
 432 static struct sk_buff *
 433 isdn_v110_idle(isdn_v110_stream *v)
 434 {
 435         struct sk_buff *skb;
 436
 437         if (v == NULL) {
 438                 /* invalid handle, no chance to proceed */
 439                 printk(KERN_WARNING "isdn_v110_sync called with NULL stream!\n");
 440                 return NULL;
 441         }
 442         if ((skb = dev_alloc_skb(v->framelen + v->skbres))) {
 443                 skb_reserve(skb, v->skbres);
 444                 memcpy(skb_put(skb, v->framelen), v->OnlineFrame, v->framelen);
 445         }
 446         return skb;
 447 }
 448
 449 struct sk_buff *
 450 isdn_v110_encode(isdn_v110_stream * v, struct sk_buff *skb)
 451 {
 452         int i;
 453         int j;
 454         int rlen;
 455         int mlen;
 456         int olen;
 457         int size;
 458         int sval1;
 459         int sval2;
 460         int nframes;
 461         unsigned char *v110buf;
 462         unsigned char *rbuf;
 463         struct sk_buff *nskb;
 464
 465         if (v == NULL) {
 466                 /* invalid handle, no chance to proceed */
 467                 printk(KERN_WARNING "isdn_v110_encode called with NULL stream!\n");
 468                 return NULL;
 469         }
 470         if (!skb) {
 471                 /* invalid skb, no chance to proceed */
 472                 printk(KERN_WARNING "isdn_v110_encode called with NULL skb!\n");
 473                 return NULL;
 474         }
 475         rlen = skb->len;
 476         nframes = (rlen + 3) / 4;
 477         v110buf = v->encodebuf;
 478         if ((nframes * 40) > v->maxsize) {
 479                 size = v->maxsize;
 480                 rlen = v->maxsize / 40;
 481         } else
 482                 size = nframes * 40;
 483         if (!(nskb = dev_alloc_skb(size + v->skbres + sizeof(int)))) {
 484                 printk(KERN_WARNING "isdn_v110_encode: Couldn't alloc skb\n");
 485                 return NULL;
 486         }
 487         skb_reserve(nskb, v->skbres + sizeof(int));
 488         if (skb->len == 0) {
 489                 memcpy(skb_put(nskb, v->framelen), v->OnlineFrame, v->framelen);
 490                 *((int *)skb_push(nskb, sizeof(int))) = 0;
 491                 return nskb;
 492         }
 493         mlen = EncodeMatrix(skb->data, rlen, v110buf, size);
 494         /* now distribute 2 or 4 bits each to the output stream! */
 495         rbuf = skb_put(nskb, size);
 496         olen = 0;
 497         sval1 = 8 - v->nbits;
 498         sval2 = v->key << sval1;
 499         for (i = 0; i < mlen; i++) {
 500                 v110buf[i] = FlipBits(v110buf[i], v->nbits);
 501                 for (j = 0; j < v->nbytes; j++) {
 502                         if (size--)
 503                                 *rbuf++ = ~v->key | (((v110buf[i] << (j * v->nbits)) & sval2) >> sval1);
 504                         else {
 505                                 printk(KERN_WARNING "isdn_v110_encode: buffers full!\n");
 506                                 goto buffer_full;
 507                         }
 508                         olen++;
 509                 }
 510         }
 511 buffer_full:
 512         skb_trim(nskb, olen);
 513         *((int *)skb_push(nskb, sizeof(int))) = rlen;
 514         return nskb;
 515 }
 516
 517 int
 518 isdn_v110_stat_callback(int idx, isdn_ctrl *c)
 519 {
 520         isdn_v110_stream *v = NULL;
 521         int i;
 522         int ret = 0;
 523
 524         if (idx < 0)
 525                 return 0;
 526         switch (c->command) {
 527                 case ISDN_STAT_BSENT:
 528                         /* Keep the send-queue of the driver filled
 529                          * with frames:
 530                          * If number of outstanding frames < 3,
 531                          * send down an Idle-Frame (or an Sync-Frame, if
 532                          * v->SyncInit != 0).
 533                          */
 534                         if (!(v = dev->v110[idx]))
 535                                 return 0;
 536                         atomic_inc(&dev->v110use[idx]);
 537                         for (i=0; i * v->framelen < c->parm.length; i++) {
 538                                 if (v->skbidle > 0) {
 539                                         v->skbidle--;
 540                                         ret = 1;
 541                                 } else {
 542                                         if (v->skbuser > 0)
 543                                                 v->skbuser--;
 544                                         ret = 0;
 545                                 }
 546                         }
 547                         for (i = v->skbuser + v->skbidle; i < 2; i++) {
 548                                 struct sk_buff *skb;
 549                                 if (v->SyncInit > 0)
 550                                         skb = isdn_v110_sync(v);
 551                                 else
 552                                         skb = isdn_v110_idle(v);
 553                                 if (skb) {
 554                                         if (dev->drv[c->driver]->interface->writebuf_skb(c->driver, c->arg, 1, skb) <= 0) {
 555                                                 dev_kfree_skb(skb);
 556                                                 break;
 557                                         } else {
 558                                                 if (v->SyncInit)
 559                                                         v->SyncInit--;
 560                                                 v->skbidle++;
 561                                         }
 562                                 } else
 563                                         break;
 564                         }
 565                         atomic_dec(&dev->v110use[idx]);
 566                         return ret;
 567                 case ISDN_STAT_DHUP:
 568                 case ISDN_STAT_BHUP:
 569                         while (1) {
 570                                 atomic_inc(&dev->v110use[idx]);
 571                                 if (atomic_dec_and_test(&dev->v110use[idx])) {
 572                                         isdn_v110_close(dev->v110[idx]);
 573                                         dev->v110[idx] = NULL;
 574                                         break;
 575                                 }
 576                                 mdelay(1);
 577                         }
 578                         break;
 579                 case ISDN_STAT_BCONN:
 580                         if (dev->v110emu[idx] && (dev->v110[idx] == NULL)) {
 581                                 int hdrlen = dev->drv[c->driver]->interface->hl_hdrlen;
 582                                 int maxsize = dev->drv[c->driver]->interface->maxbufsize;
 583                                 atomic_inc(&dev->v110use[idx]);
 584                                 switch (dev->v110emu[idx]) {
 585                                         case ISDN_PROTO_L2_V11096:
 586                                                 dev->v110[idx] = isdn_v110_open(V110_9600, hdrlen, maxsize);
 587                                                 break;
 588                                         case ISDN_PROTO_L2_V11019:
 589                                                 dev->v110[idx] = isdn_v110_open(V110_19200, hdrlen, maxsize);
 590                                                 break;
 591                                         case ISDN_PROTO_L2_V11038:
 592                                                 dev->v110[idx] = isdn_v110_open(V110_38400, hdrlen, maxsize);
 593                                                 break;
 594                                         default:;
 595                                 }
 596                                 if ((v = dev->v110[idx])) {
 597                                         while (v->SyncInit) {
 598                                                 struct sk_buff *skb = isdn_v110_sync(v);
 599                                                 if (dev->drv[c->driver]->interface->writebuf_skb(c->driver, c->arg, 1, skb) <= 0) {
 600                                                         dev_kfree_skb(skb);
 601                                                         /* Unable to send, try later */
 602                                                         break;
 603                                                 }
 604                                                 v->SyncInit--;
 605                                                 v->skbidle++;
 606                                         }
 607                                 } else
 608                                         printk(KERN_WARNING "isdn_v110: Couldn't open stream for chan %d\n", idx);
 609                                 atomic_dec(&dev->v110use[idx]);
 610                         }
 611                         break;
 612                 default:
 613                         return 0;
 614         }
 615         return 0;
 616 }