drivers/net/hamradio/hdlcdrv.c

   1 /*****************************************************************************/
   2
   3 /*
   4  *      hdlcdrv.c  -- HDLC packet radio network driver.
   5  *
   6  *      Copyright (C) 1996-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
   7  *
   8  *      This program is free software; you can redistribute it and/or modify
   9  *      it under the terms of the GNU General Public License as published by
  10  *      the Free Software Foundation; either version 2 of the License, or
  11  *      (at your option) any later version.
  12  *
  13  *      This program is distributed in the hope that it will be useful,
  14  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *      GNU General Public License for more details.
  17  *
  18  *      You should have received a copy of the GNU General Public License
  19  *      along with this program; if not, write to the Free Software
  20  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  *  Please note that the GPL allows you to use the driver, NOT the radio.
  23  *  In order to use the radio, you need a license from the communications
  24  *  authority of your country.
  25  *
  26  *  The driver was derived from Donald Beckers skeleton.c
  27  *      Written 1993-94 by Donald Becker.
  28  *
  29  *  History:
  30  *   0.1  21.09.1996  Started
  31  *        18.10.1996  Changed to new user space access routines
  32  *                    (copy_{to,from}_user)
  33  *   0.2  21.11.1996  various small changes
  34  *   0.3  03.03.1997  fixed (hopefully) IP not working with ax.25 as a module
  35  *   0.4  16.04.1997  init code/data tagged
  36  *   0.5  30.07.1997  made HDLC buffers bigger (solves a problem with the
  37  *                    soundmodem driver)
  38  *   0.6  05.04.1998  add spinlocks
  39  *   0.7  03.08.1999  removed some old compatibility cruft
  40  *   0.8  12.02.2000  adapted to softnet driver interface
  41  */
  42
  43 /*****************************************************************************/
  44
  45 #include <linux/module.h>
  46 #include <linux/types.h>
  47 #include <linux/net.h>
  48 #include <linux/in.h>
  49 #include <linux/if.h>
  50 #include <linux/slab.h>
  51 #include <linux/errno.h>
  52 #include <linux/init.h>
  53 #include <linux/bitops.h>
  54
  55 #include <linux/netdevice.h>
  56 #include <linux/if_arp.h>
  57 #include <linux/skbuff.h>
  58 #include <linux/hdlcdrv.h>
  59 #include <linux/random.h>
  60 #include <net/ax25.h>
  61 #include <asm/uaccess.h>
  62
  63 #include <linux/crc-ccitt.h>
  64
  65 /* --------------------------------------------------------------------- */
  66
  67 #define KISS_VERBOSE
  68
  69 /* --------------------------------------------------------------------- */
  70
  71 #define PARAM_TXDELAY   1
  72 #define PARAM_PERSIST   2
  73 #define PARAM_SLOTTIME  3
  74 #define PARAM_TXTAIL    4
  75 #define PARAM_FULLDUP   5
  76 #define PARAM_HARDWARE  6
  77 #define PARAM_RETURN    255
  78
  79 /* --------------------------------------------------------------------- */
  80 /*
  81  * the CRC routines are stolen from WAMPES
  82  * by Dieter Deyke
  83  */
  84
  85
  86 /*---------------------------------------------------------------------------*/
  87
  88 static inline void append_crc_ccitt(unsigned char *buffer, int len)
  89 {
  90         unsigned int crc = crc_ccitt(0xffff, buffer, len) ^ 0xffff;
  91         buffer += len;
  92         *buffer++ = crc;
  93         *buffer++ = crc >> 8;
  94 }
  95
  96 /*---------------------------------------------------------------------------*/
  97
  98 static inline int check_crc_ccitt(const unsigned char *buf, int cnt)
  99 {
 100         return (crc_ccitt(0xffff, buf, cnt) & 0xffff) == 0xf0b8;
 101 }
 102
 103 /*---------------------------------------------------------------------------*/
 104
 105 #if 0
 106 static int calc_crc_ccitt(const unsigned char *buf, int cnt)
 107 {
 108         unsigned int crc = 0xffff;
 109
 110         for (; cnt > 0; cnt--)
 111                 crc = (crc >> 8) ^ crc_ccitt_table[(crc ^ *buf++) & 0xff];
 112         crc ^= 0xffff;
 113         return (crc & 0xffff);
 114 }
 115 #endif
 116
 117 /* ---------------------------------------------------------------------- */
 118
 119 #define tenms_to_2flags(s,tenms) ((tenms * s->par.bitrate) / 100 / 16)
 120
 121 /* ---------------------------------------------------------------------- */
 122 /*
 123  * The HDLC routines
 124  */
 125
 126 static int hdlc_rx_add_bytes(struct hdlcdrv_state *s, unsigned int bits,
 127                              int num)
 128 {
 129         int added = 0;
 130
 131         while (s->hdlcrx.rx_state && num >= 8) {
 132                 if (s->hdlcrx.len >= sizeof(s->hdlcrx.buffer)) {
 133                         s->hdlcrx.rx_state = 0;
 134                         return 0;
 135                 }
 136                 *s->hdlcrx.bp++ = bits >> (32-num);
 137                 s->hdlcrx.len++;
 138                 num -= 8;
 139                 added += 8;
 140         }
 141         return added;
 142 }
 143
 144 static void hdlc_rx_flag(struct net_device *dev, struct hdlcdrv_state *s)
 145 {
 146         struct sk_buff *skb;
 147         int pkt_len;
 148         unsigned char *cp;
 149
 150         if (s->hdlcrx.len < 4)
 151                 return;
 152         if (!check_crc_ccitt(s->hdlcrx.buffer, s->hdlcrx.len))
 153                 return;
 154         pkt_len = s->hdlcrx.len - 2 + 1; /* KISS kludge */
 155         if (!(skb = dev_alloc_skb(pkt_len))) {
 156                 printk("%s: memory squeeze, dropping packet\n", dev->name);
 157                 s->stats.rx_dropped++;
 158                 return;
 159         }
 160         cp = skb_put(skb, pkt_len);
 161         *cp++ = 0; /* KISS kludge */
 162         memcpy(cp, s->hdlcrx.buffer, pkt_len - 1);
 163         skb->protocol = ax25_type_trans(skb, dev);
 164         netif_rx(skb);
 165         dev->last_rx = jiffies;
 166         s->stats.rx_packets++;
 167 }
 168
 169 void hdlcdrv_receiver(struct net_device *dev, struct hdlcdrv_state *s)
 170 {
 171         int i;
 172         unsigned int mask1, mask2, mask3, mask4, mask5, mask6, word;
 173
 174         if (!s || s->magic != HDLCDRV_MAGIC)
 175                 return;
 176         if (test_and_set_bit(0, &s->hdlcrx.in_hdlc_rx))
 177                 return;
 178
 179         while (!hdlcdrv_hbuf_empty(&s->hdlcrx.hbuf)) {
 180                 word = hdlcdrv_hbuf_get(&s->hdlcrx.hbuf);
 181
 182 #ifdef HDLCDRV_DEBUG
 183                 hdlcdrv_add_bitbuffer_word(&s->bitbuf_hdlc, word);
 184 #endif /* HDLCDRV_DEBUG */
 185                 s->hdlcrx.bitstream >>= 16;
 186                 s->hdlcrx.bitstream |= word << 16;
 187                 s->hdlcrx.bitbuf >>= 16;
 188                 s->hdlcrx.bitbuf |= word << 16;
 189                 s->hdlcrx.numbits += 16;
 190                 for(i = 15, mask1 = 0x1fc00, mask2 = 0x1fe00, mask3 = 0x0fc00,
 191                     mask4 = 0x1f800, mask5 = 0xf800, mask6 = 0xffff;
 192                     i >= 0;
 193                     i--, mask1 <<= 1, mask2 <<= 1, mask3 <<= 1, mask4 <<= 1,
 194                     mask5 <<= 1, mask6 = (mask6 << 1) | 1) {
 195                         if ((s->hdlcrx.bitstream & mask1) == mask1)
 196                                 s->hdlcrx.rx_state = 0; /* abort received */
 197                         else if ((s->hdlcrx.bitstream & mask2) == mask3) {
 198                                 /* flag received */
 199                                 if (s->hdlcrx.rx_state) {
 200                                         hdlc_rx_add_bytes(s, s->hdlcrx.bitbuf
 201                                                           << (8+i),
 202                                                           s->hdlcrx.numbits
 203                                                           -8-i);
 204                                         hdlc_rx_flag(dev, s);
 205                                 }
 206                                 s->hdlcrx.len = 0;
 207                                 s->hdlcrx.bp = s->hdlcrx.buffer;
 208                                 s->hdlcrx.rx_state = 1;
 209                                 s->hdlcrx.numbits = i;
 210                         } else if ((s->hdlcrx.bitstream & mask4) == mask5) {
 211                                 /* stuffed bit */
 212                                 s->hdlcrx.numbits--;
 213                                 s->hdlcrx.bitbuf = (s->hdlcrx.bitbuf & (~mask6)) |
 214                                         ((s->hdlcrx.bitbuf & mask6) << 1);
 215                         }
 216                 }
 217                 s->hdlcrx.numbits -= hdlc_rx_add_bytes(s, s->hdlcrx.bitbuf,
 218                                                        s->hdlcrx.numbits);
 219         }
 220         clear_bit(0, &s->hdlcrx.in_hdlc_rx);
 221 }
 222
 223 /* ---------------------------------------------------------------------- */
 224
 225 static inline void do_kiss_params(struct hdlcdrv_state *s,
 226                                   unsigned char *data, unsigned long len)
 227 {
 228
 229 #ifdef KISS_VERBOSE
 230 #define PKP(a,b) printk(KERN_INFO "hdlcdrv.c: channel params: " a "\n", b)
 231 #else /* KISS_VERBOSE */
 232 #define PKP(a,b)
 233 #endif /* KISS_VERBOSE */
 234
 235         if (len < 2)
 236                 return;
 237         switch(data[0]) {
 238         case PARAM_TXDELAY:
 239                 s->ch_params.tx_delay = data[1];
 240                 PKP("TX delay = %ums", 10 * s->ch_params.tx_delay);
 241                 break;
 242         case PARAM_PERSIST:
 243                 s->ch_params.ppersist = data[1];
 244                 PKP("p persistence = %u", s->ch_params.ppersist);
 245                 break;
 246         case PARAM_SLOTTIME:
 247                 s->ch_params.slottime = data[1];
 248                 PKP("slot time = %ums", s->ch_params.slottime);
 249                 break;
 250         case PARAM_TXTAIL:
 251                 s->ch_params.tx_tail = data[1];
 252                 PKP("TX tail = %ums", s->ch_params.tx_tail);
 253                 break;
 254         case PARAM_FULLDUP:
 255                 s->ch_params.fulldup = !!data[1];
 256                 PKP("%s duplex", s->ch_params.fulldup ? "full" : "half");
 257                 break;
 258         default:
 259                 break;
 260         }
 261 #undef PKP
 262 }
 263
 264 /* ---------------------------------------------------------------------- */
 265
 266 void hdlcdrv_transmitter(struct net_device *dev, struct hdlcdrv_state *s)
 267 {
 268         unsigned int mask1, mask2, mask3;
 269         int i;
 270         struct sk_buff *skb;
 271         int pkt_len;
 272
 273         if (!s || s->magic != HDLCDRV_MAGIC)
 274                 return;
 275         if (test_and_set_bit(0, &s->hdlctx.in_hdlc_tx))
 276                 return;
 277         for (;;) {
 278                 if (s->hdlctx.numbits >= 16) {
 279                         if (hdlcdrv_hbuf_full(&s->hdlctx.hbuf)) {
 280                                 clear_bit(0, &s->hdlctx.in_hdlc_tx);
 281                                 return;
 282                         }
 283                         hdlcdrv_hbuf_put(&s->hdlctx.hbuf, s->hdlctx.bitbuf);
 284                         s->hdlctx.bitbuf >>= 16;
 285                         s->hdlctx.numbits -= 16;
 286                 }
 287                 switch (s->hdlctx.tx_state) {
 288                 default:
 289                         clear_bit(0, &s->hdlctx.in_hdlc_tx);
 290                         return;
 291                 case 0:
 292                 case 1:
 293                         if (s->hdlctx.numflags) {
 294                                 s->hdlctx.numflags--;
 295                                 s->hdlctx.bitbuf |=
 296                                         0x7e7e << s->hdlctx.numbits;
 297                                 s->hdlctx.numbits += 16;
 298                                 break;
 299                         }
 300                         if (s->hdlctx.tx_state == 1) {
 301                                 clear_bit(0, &s->hdlctx.in_hdlc_tx);
 302                                 return;
 303                         }
 304                         if (!(skb = s->skb)) {
 305                                 int flgs = tenms_to_2flags(s, s->ch_params.tx_tail);
 306                                 if (flgs < 2)
 307                                         flgs = 2;
 308                                 s->hdlctx.tx_state = 1;
 309                                 s->hdlctx.numflags = flgs;
 310                                 break;
 311                         }
 312                         s->skb = NULL;
 313                         netif_wake_queue(dev);
 314                         pkt_len = skb->len-1; /* strip KISS byte */
 315                         if (pkt_len >= HDLCDRV_MAXFLEN || pkt_len < 2) {
 316                                 s->hdlctx.tx_state = 0;
 317                                 s->hdlctx.numflags = 1;
 318                                 dev_kfree_skb_irq(skb);
 319                                 break;
 320                         }
 321                         skb_copy_from_linear_data_offset(skb, 1,
 322                                                          s->hdlctx.buffer,
 323                                                          pkt_len);
 324                         dev_kfree_skb_irq(skb);
 325                         s->hdlctx.bp = s->hdlctx.buffer;
 326                         append_crc_ccitt(s->hdlctx.buffer, pkt_len);
 327                         s->hdlctx.len = pkt_len+2; /* the appended CRC */
 328                         s->hdlctx.tx_state = 2;
 329                         s->hdlctx.bitstream = 0;
 330                         s->stats.tx_packets++;
 331                         break;
 332                 case 2:
 333                         if (!s->hdlctx.len) {
 334                                 s->hdlctx.tx_state = 0;
 335                                 s->hdlctx.numflags = 1;
 336                                 break;
 337                         }
 338                         s->hdlctx.len--;
 339                         s->hdlctx.bitbuf |= *s->hdlctx.bp <<
 340                                 s->hdlctx.numbits;
 341                         s->hdlctx.bitstream >>= 8;
 342                         s->hdlctx.bitstream |= (*s->hdlctx.bp++) << 16;
 343                         mask1 = 0x1f000;
 344                         mask2 = 0x10000;
 345                         mask3 = 0xffffffff >> (31-s->hdlctx.numbits);
 346                         s->hdlctx.numbits += 8;
 347                         for(i = 0; i < 8; i++, mask1 <<= 1, mask2 <<= 1,
 348                             mask3 = (mask3 << 1) | 1) {
 349                                 if ((s->hdlctx.bitstream & mask1) != mask1)
 350                                         continue;
 351                                 s->hdlctx.bitstream &= ~mask2;
 352                                 s->hdlctx.bitbuf =
 353                                         (s->hdlctx.bitbuf & mask3) |
 354                                                 ((s->hdlctx.bitbuf &
 355                                                  (~mask3)) << 1);
 356                                 s->hdlctx.numbits++;
 357                                 mask3 = (mask3 << 1) | 1;
 358                         }
 359                         break;
 360                 }
 361         }
 362 }
 363
 364 /* ---------------------------------------------------------------------- */
 365
 366 static void start_tx(struct net_device *dev, struct hdlcdrv_state *s)
 367 {
 368         s->hdlctx.tx_state = 0;
 369         s->hdlctx.numflags = tenms_to_2flags(s, s->ch_params.tx_delay);
 370         s->hdlctx.bitbuf = s->hdlctx.bitstream = s->hdlctx.numbits = 0;
 371         hdlcdrv_transmitter(dev, s);
 372         s->hdlctx.ptt = 1;
 373         s->ptt_keyed++;
 374 }
 375
 376 /* ---------------------------------------------------------------------- */
 377
 378 void hdlcdrv_arbitrate(struct net_device *dev, struct hdlcdrv_state *s)
 379 {
 380         if (!s || s->magic != HDLCDRV_MAGIC || s->hdlctx.ptt || !s->skb)
 381                 return;
 382         if (s->ch_params.fulldup) {
 383                 start_tx(dev, s);
 384                 return;
 385         }
 386         if (s->hdlcrx.dcd) {
 387                 s->hdlctx.slotcnt = s->ch_params.slottime;
 388                 return;
 389         }
 390         if ((--s->hdlctx.slotcnt) > 0)
 391                 return;
 392         s->hdlctx.slotcnt = s->ch_params.slottime;
 393         if ((random32() % 256) > s->ch_params.ppersist)
 394                 return;
 395         start_tx(dev, s);
 396 }
 397
 398 /* --------------------------------------------------------------------- */
 399 /*
 400  * ===================== network driver interface =========================
 401  */
 402
 403 static int hdlcdrv_send_packet(struct sk_buff *skb, struct net_device *dev)
 404 {
 405         struct hdlcdrv_state *sm = netdev_priv(dev);
 406
 407         if (skb->data[0] != 0) {
 408                 do_kiss_params(sm, skb->data, skb->len);
 409                 dev_kfree_skb(skb);
 410                 return 0;
 411         }
 412         if (sm->skb)
 413                 return -1;
 414         netif_stop_queue(dev);
 415         sm->skb = skb;
 416         return 0;
 417 }
 418
 419 /* --------------------------------------------------------------------- */
 420
 421 static int hdlcdrv_set_mac_address(struct net_device *dev, void *addr)
 422 {
 423         struct sockaddr *sa = (struct sockaddr *)addr;
 424
 425         /* addr is an AX.25 shifted ASCII mac address */
 426         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 427         return 0;
 428 }
 429
 430 /* --------------------------------------------------------------------- */
 431
 432 static struct net_device_stats *hdlcdrv_get_stats(struct net_device *dev)
 433 {
 434         struct hdlcdrv_state *sm = netdev_priv(dev);
 435
 436         /*
 437          * Get the current statistics.  This may be called with the
 438          * card open or closed.
 439          */
 440         return &sm->stats;
 441 }
 442
 443 /* --------------------------------------------------------------------- */
 444 /*
 445  * Open/initialize the board. This is called (in the current kernel)
 446  * sometime after booting when the 'ifconfig' program is run.
 447  *
 448  * This routine should set everything up anew at each open, even
 449  * registers that "should" only need to be set once at boot, so that
 450  * there is non-reboot way to recover if something goes wrong.
 451  */
 452
 453 static int hdlcdrv_open(struct net_device *dev)
 454 {
 455         struct hdlcdrv_state *s = netdev_priv(dev);
 456         int i;
 457
 458         if (!s->ops || !s->ops->open)
 459                 return -ENODEV;
 460
 461         /*
 462          * initialise some variables
 463          */
 464         s->opened = 1;
 465         s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
 466         s->hdlcrx.in_hdlc_rx = 0;
 467         s->hdlcrx.rx_state = 0;
 468
 469         s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
 470         s->hdlctx.in_hdlc_tx = 0;
 471         s->hdlctx.tx_state = 1;
 472         s->hdlctx.numflags = 0;
 473         s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
 474         s->hdlctx.ptt = 0;
 475         s->hdlctx.slotcnt = s->ch_params.slottime;
 476         s->hdlctx.calibrate = 0;
 477
 478         i = s->ops->open(dev);
 479         if (i)
 480                 return i;
 481         netif_start_queue(dev);
 482         return 0;
 483 }
 484
 485 /* --------------------------------------------------------------------- */
 486 /*
 487  * The inverse routine to hdlcdrv_open().
 488  */
 489
 490 static int hdlcdrv_close(struct net_device *dev)
 491 {
 492         struct hdlcdrv_state *s = netdev_priv(dev);
 493         int i = 0;
 494
 495         netif_stop_queue(dev);
 496
 497         if (s->ops && s->ops->close)
 498                 i = s->ops->close(dev);
 499         if (s->skb)
 500                 dev_kfree_skb(s->skb);
 501         s->skb = NULL;
 502         s->opened = 0;
 503         return i;
 504 }
 505
 506 /* --------------------------------------------------------------------- */
 507
 508 static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 509 {
 510         struct hdlcdrv_state *s = netdev_priv(dev);
 511         struct hdlcdrv_ioctl bi;
 512
 513         if (cmd != SIOCDEVPRIVATE) {
 514                 if (s->ops && s->ops->ioctl)
 515                         return s->ops->ioctl(dev, ifr, &bi, cmd);
 516                 return -ENOIOCTLCMD;
 517         }
 518         if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
 519                 return -EFAULT;
 520
 521         switch (bi.cmd) {
 522         default:
 523                 if (s->ops && s->ops->ioctl)
 524                         return s->ops->ioctl(dev, ifr, &bi, cmd);
 525                 return -ENOIOCTLCMD;
 526
 527         case HDLCDRVCTL_GETCHANNELPAR:
 528                 bi.data.cp.tx_delay = s->ch_params.tx_delay;
 529                 bi.data.cp.tx_tail = s->ch_params.tx_tail;
 530                 bi.data.cp.slottime = s->ch_params.slottime;
 531                 bi.data.cp.ppersist = s->ch_params.ppersist;
 532                 bi.data.cp.fulldup = s->ch_params.fulldup;
 533                 break;
 534
 535         case HDLCDRVCTL_SETCHANNELPAR:
 536                 if (!capable(CAP_NET_ADMIN))
 537                         return -EACCES;
 538                 s->ch_params.tx_delay = bi.data.cp.tx_delay;
 539                 s->ch_params.tx_tail = bi.data.cp.tx_tail;
 540                 s->ch_params.slottime = bi.data.cp.slottime;
 541                 s->ch_params.ppersist = bi.data.cp.ppersist;
 542                 s->ch_params.fulldup = bi.data.cp.fulldup;
 543                 s->hdlctx.slotcnt = 1;
 544                 return 0;
 545
 546         case HDLCDRVCTL_GETMODEMPAR:
 547                 bi.data.mp.iobase = dev->base_addr;
 548                 bi.data.mp.irq = dev->irq;
 549                 bi.data.mp.dma = dev->dma;
 550                 bi.data.mp.dma2 = s->ptt_out.dma2;
 551                 bi.data.mp.seriobase = s->ptt_out.seriobase;
 552                 bi.data.mp.pariobase = s->ptt_out.pariobase;
 553                 bi.data.mp.midiiobase = s->ptt_out.midiiobase;
 554                 break;
 555
 556         case HDLCDRVCTL_SETMODEMPAR:
 557                 if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
 558                         return -EACCES;
 559                 dev->base_addr = bi.data.mp.iobase;
 560                 dev->irq = bi.data.mp.irq;
 561                 dev->dma = bi.data.mp.dma;
 562                 s->ptt_out.dma2 = bi.data.mp.dma2;
 563                 s->ptt_out.seriobase = bi.data.mp.seriobase;
 564                 s->ptt_out.pariobase = bi.data.mp.pariobase;
 565                 s->ptt_out.midiiobase = bi.data.mp.midiiobase;
 566                 return 0;
 567
 568         case HDLCDRVCTL_GETSTAT:
 569                 bi.data.cs.ptt = hdlcdrv_ptt(s);
 570                 bi.data.cs.dcd = s->hdlcrx.dcd;
 571                 bi.data.cs.ptt_keyed = s->ptt_keyed;
 572                 bi.data.cs.tx_packets = s->stats.tx_packets;
 573                 bi.data.cs.tx_errors = s->stats.tx_errors;
 574                 bi.data.cs.rx_packets = s->stats.rx_packets;
 575                 bi.data.cs.rx_errors = s->stats.rx_errors;
 576                 break;
 577
 578         case HDLCDRVCTL_OLDGETSTAT:
 579                 bi.data.ocs.ptt = hdlcdrv_ptt(s);
 580                 bi.data.ocs.dcd = s->hdlcrx.dcd;
 581                 bi.data.ocs.ptt_keyed = s->ptt_keyed;
 582                 break;
 583
 584         case HDLCDRVCTL_CALIBRATE:
 585                 if(!capable(CAP_SYS_RAWIO))
 586                         return -EPERM;
 587                 s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
 588                 return 0;
 589
 590         case HDLCDRVCTL_GETSAMPLES:
 591 #ifndef HDLCDRV_DEBUG
 592                 return -EPERM;
 593 #else /* HDLCDRV_DEBUG */
 594                 if (s->bitbuf_channel.rd == s->bitbuf_channel.wr)
 595                         return -EAGAIN;
 596                 bi.data.bits =
 597                         s->bitbuf_channel.buffer[s->bitbuf_channel.rd];
 598                 s->bitbuf_channel.rd = (s->bitbuf_channel.rd+1) %
 599                         sizeof(s->bitbuf_channel.buffer);
 600                 break;
 601 #endif /* HDLCDRV_DEBUG */
 602
 603         case HDLCDRVCTL_GETBITS:
 604 #ifndef HDLCDRV_DEBUG
 605                 return -EPERM;
 606 #else /* HDLCDRV_DEBUG */
 607                 if (s->bitbuf_hdlc.rd == s->bitbuf_hdlc.wr)
 608                         return -EAGAIN;
 609                 bi.data.bits =
 610                         s->bitbuf_hdlc.buffer[s->bitbuf_hdlc.rd];
 611                 s->bitbuf_hdlc.rd = (s->bitbuf_hdlc.rd+1) %
 612                         sizeof(s->bitbuf_hdlc.buffer);
 613                 break;
 614 #endif /* HDLCDRV_DEBUG */
 615
 616         case HDLCDRVCTL_DRIVERNAME:
 617                 if (s->ops && s->ops->drvname) {
 618                         strncpy(bi.data.drivername, s->ops->drvname,
 619                                 sizeof(bi.data.drivername));
 620                         break;
 621                 }
 622                 bi.data.drivername[0] = '\0';
 623                 break;
 624
 625         }
 626         if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
 627                 return -EFAULT;
 628         return 0;
 629
 630 }
 631
 632 /* --------------------------------------------------------------------- */
 633
 634 /*
 635  * Initialize fields in hdlcdrv
 636  */
 637 static void hdlcdrv_setup(struct net_device *dev)
 638 {
 639         static const struct hdlcdrv_channel_params dflt_ch_params = {
 640                 20, 2, 10, 40, 0
 641         };
 642         struct hdlcdrv_state *s = netdev_priv(dev);
 643
 644         /*
 645          * initialize the hdlcdrv_state struct
 646          */
 647         s->ch_params = dflt_ch_params;
 648         s->ptt_keyed = 0;
 649
 650         spin_lock_init(&s->hdlcrx.hbuf.lock);
 651         s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
 652         s->hdlcrx.in_hdlc_rx = 0;
 653         s->hdlcrx.rx_state = 0;
 654
 655         spin_lock_init(&s->hdlctx.hbuf.lock);
 656         s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
 657         s->hdlctx.in_hdlc_tx = 0;
 658         s->hdlctx.tx_state = 1;
 659         s->hdlctx.numflags = 0;
 660         s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
 661         s->hdlctx.ptt = 0;
 662         s->hdlctx.slotcnt = s->ch_params.slottime;
 663         s->hdlctx.calibrate = 0;
 664
 665 #ifdef HDLCDRV_DEBUG
 666         s->bitbuf_channel.rd = s->bitbuf_channel.wr = 0;
 667         s->bitbuf_channel.shreg = 0x80;
 668
 669         s->bitbuf_hdlc.rd = s->bitbuf_hdlc.wr = 0;
 670         s->bitbuf_hdlc.shreg = 0x80;
 671 #endif /* HDLCDRV_DEBUG */
 672
 673         /*
 674          * initialize the device struct
 675          */
 676         dev->open = hdlcdrv_open;
 677         dev->stop = hdlcdrv_close;
 678         dev->do_ioctl = hdlcdrv_ioctl;
 679         dev->hard_start_xmit = hdlcdrv_send_packet;
 680         dev->get_stats = hdlcdrv_get_stats;
 681
 682         /* Fill in the fields of the device structure */
 683
 684         s->skb = NULL;
 685
 686         dev->header_ops = &ax25_header_ops;
 687         dev->set_mac_address = hdlcdrv_set_mac_address;
 688
 689         dev->type = ARPHRD_AX25;           /* AF_AX25 device */
 690         dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
 691         dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
 692         dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
 693         memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
 694         memcpy(dev->dev_addr, &ax25_defaddr, AX25_ADDR_LEN);
 695         dev->tx_queue_len = 16;
 696 }
 697
 698 /* --------------------------------------------------------------------- */
 699 struct net_device *hdlcdrv_register(const struct hdlcdrv_ops *ops,
 700                                     unsigned int privsize, const char *ifname,
 701                                     unsigned int baseaddr, unsigned int irq,
 702                                     unsigned int dma)
 703 {
 704         struct net_device *dev;
 705         struct hdlcdrv_state *s;
 706         int err;
 707
 708         BUG_ON(ops == NULL);
 709
 710         if (privsize < sizeof(struct hdlcdrv_state))
 711                 privsize = sizeof(struct hdlcdrv_state);
 712
 713         dev = alloc_netdev(privsize, ifname, hdlcdrv_setup);
 714         if (!dev)
 715                 return ERR_PTR(-ENOMEM);
 716
 717         /*
 718          * initialize part of the hdlcdrv_state struct
 719          */
 720         s = netdev_priv(dev);
 721         s->magic = HDLCDRV_MAGIC;
 722         s->ops = ops;
 723         dev->base_addr = baseaddr;
 724         dev->irq = irq;
 725         dev->dma = dma;
 726
 727         err = register_netdev(dev);
 728         if (err < 0) {
 729                 printk(KERN_WARNING "hdlcdrv: cannot register net "
 730                        "device %s\n", dev->name);
 731                 free_netdev(dev);
 732                 dev = ERR_PTR(err);
 733         }
 734         return dev;
 735 }
 736
 737 /* --------------------------------------------------------------------- */
 738
 739 void hdlcdrv_unregister(struct net_device *dev)
 740 {
 741         struct hdlcdrv_state *s = netdev_priv(dev);
 742
 743         BUG_ON(s->magic != HDLCDRV_MAGIC);
 744
 745         if (s->opened && s->ops->close)
 746                 s->ops->close(dev);
 747         unregister_netdev(dev);
 748
 749         free_netdev(dev);
 750 }
 751
 752 /* --------------------------------------------------------------------- */
 753
 754 EXPORT_SYMBOL(hdlcdrv_receiver);
 755 EXPORT_SYMBOL(hdlcdrv_transmitter);
 756 EXPORT_SYMBOL(hdlcdrv_arbitrate);
 757 EXPORT_SYMBOL(hdlcdrv_register);
 758 EXPORT_SYMBOL(hdlcdrv_unregister);
 759
 760 /* --------------------------------------------------------------------- */
 761
 762 static int __init hdlcdrv_init_driver(void)
 763 {
 764         printk(KERN_INFO "hdlcdrv: (C) 1996-2000 Thomas Sailer HB9JNX/AE4WA\n");
 765         printk(KERN_INFO "hdlcdrv: version 0.8 compiled " __TIME__ " " __DATE__ "\n");
 766         return 0;
 767 }
 768
 769 /* --------------------------------------------------------------------- */
 770
 771 static void __exit hdlcdrv_cleanup_driver(void)
 772 {
 773         printk(KERN_INFO "hdlcdrv: cleanup\n");
 774 }
 775
 776 /* --------------------------------------------------------------------- */
 777
 778 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
 779 MODULE_DESCRIPTION("Packet Radio network interface HDLC encoder/decoder");
 780 MODULE_LICENSE("GPL");
 781 module_init(hdlcdrv_init_driver);
 782 module_exit(hdlcdrv_cleanup_driver);
 783
 784 /* --------------------------------------------------------------------- */