b89959a596d7f615e2db9f4b23a27980e11c551f
[linux-2.6.git] / 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/config.h>
46 #include <linux/module.h>
47 #include <linux/types.h>
48 #include <linux/net.h>
49 #include <linux/in.h>
50 #include <linux/if.h>
51 #include <linux/slab.h>
52 #include <linux/errno.h>
53 #include <linux/init.h>
54 #include <linux/bitops.h>
55 #include <asm/uaccess.h>
56
57 #include <linux/netdevice.h>
58 #include <linux/if_arp.h>
59 #include <linux/etherdevice.h>
60 #include <linux/skbuff.h>
61 #include <linux/hdlcdrv.h>
62 /* prototypes for ax25_encapsulate and ax25_rebuild_header */
63 #include <net/ax25.h> 
64
65 /* make genksyms happy */
66 #include <linux/ip.h>
67 #include <linux/udp.h>
68 #include <linux/tcp.h>
69 #include <linux/crc-ccitt.h>
70
71 /* --------------------------------------------------------------------- */
72
73 /*
74  * The name of the card. Is used for messages and in the requests for
75  * io regions, irqs and dma channels
76  */
77
78 static char ax25_bcast[AX25_ADDR_LEN] =
79 {'Q' << 1, 'S' << 1, 'T' << 1, ' ' << 1, ' ' << 1, ' ' << 1, '0' << 1};
80 static char ax25_nocall[AX25_ADDR_LEN] =
81 {'L' << 1, 'I' << 1, 'N' << 1, 'U' << 1, 'X' << 1, ' ' << 1, '1' << 1};
82
83 /* --------------------------------------------------------------------- */
84
85 #define KISS_VERBOSE
86
87 /* --------------------------------------------------------------------- */
88
89 #define PARAM_TXDELAY   1
90 #define PARAM_PERSIST   2
91 #define PARAM_SLOTTIME  3
92 #define PARAM_TXTAIL    4
93 #define PARAM_FULLDUP   5
94 #define PARAM_HARDWARE  6
95 #define PARAM_RETURN    255
96
97 /* --------------------------------------------------------------------- */
98 /*
99  * the CRC routines are stolen from WAMPES
100  * by Dieter Deyke
101  */
102
103
104 /*---------------------------------------------------------------------------*/
105
106 static inline void append_crc_ccitt(unsigned char *buffer, int len)
107 {
108         unsigned int crc = crc_ccitt(0xffff, buffer, len) ^ 0xffff;
109         *buffer++ = crc;
110         *buffer++ = crc >> 8;
111 }
112
113 /*---------------------------------------------------------------------------*/
114
115 static inline int check_crc_ccitt(const unsigned char *buf, int cnt)
116 {
117         return (crc_ccitt(0xffff, buf, cnt) & 0xffff) == 0xf0b8;
118 }
119
120 /*---------------------------------------------------------------------------*/
121
122 #if 0
123 static int calc_crc_ccitt(const unsigned char *buf, int cnt)
124 {
125         unsigned int crc = 0xffff;
126
127         for (; cnt > 0; cnt--)
128                 crc = (crc >> 8) ^ crc_ccitt_table[(crc ^ *buf++) & 0xff];
129         crc ^= 0xffff;
130         return (crc & 0xffff);
131 }
132 #endif
133
134 /* ---------------------------------------------------------------------- */
135
136 #define tenms_to_2flags(s,tenms) ((tenms * s->par.bitrate) / 100 / 16)
137
138 /* ---------------------------------------------------------------------- */
139 /*
140  * The HDLC routines
141  */
142
143 static int hdlc_rx_add_bytes(struct hdlcdrv_state *s, unsigned int bits, 
144                              int num)
145 {
146         int added = 0;
147         
148         while (s->hdlcrx.rx_state && num >= 8) {
149                 if (s->hdlcrx.len >= sizeof(s->hdlcrx.buffer)) {
150                         s->hdlcrx.rx_state = 0;
151                         return 0;
152                 }
153                 *s->hdlcrx.bp++ = bits >> (32-num);
154                 s->hdlcrx.len++;
155                 num -= 8;
156                 added += 8;
157         }
158         return added;
159 }
160
161 static void hdlc_rx_flag(struct net_device *dev, struct hdlcdrv_state *s)
162 {
163         struct sk_buff *skb;
164         int pkt_len;
165         unsigned char *cp;
166
167         if (s->hdlcrx.len < 4) 
168                 return;
169         if (!check_crc_ccitt(s->hdlcrx.buffer, s->hdlcrx.len)) 
170                 return;
171         pkt_len = s->hdlcrx.len - 2 + 1; /* KISS kludge */
172         if (!(skb = dev_alloc_skb(pkt_len))) {
173                 printk("%s: memory squeeze, dropping packet\n", dev->name);
174                 s->stats.rx_dropped++;
175                 return;
176         }
177         skb->dev = dev;
178         cp = skb_put(skb, pkt_len);
179         *cp++ = 0; /* KISS kludge */
180         memcpy(cp, s->hdlcrx.buffer, pkt_len - 1);
181         skb->protocol = htons(ETH_P_AX25);
182         skb->mac.raw = skb->data;
183         netif_rx(skb);
184         dev->last_rx = jiffies;
185         s->stats.rx_packets++;
186 }
187
188 void hdlcdrv_receiver(struct net_device *dev, struct hdlcdrv_state *s)
189 {
190         int i;
191         unsigned int mask1, mask2, mask3, mask4, mask5, mask6, word;
192         
193         if (!s || s->magic != HDLCDRV_MAGIC) 
194                 return;
195         if (test_and_set_bit(0, &s->hdlcrx.in_hdlc_rx))
196                 return;
197
198         while (!hdlcdrv_hbuf_empty(&s->hdlcrx.hbuf)) {
199                 word = hdlcdrv_hbuf_get(&s->hdlcrx.hbuf);       
200
201 #ifdef HDLCDRV_DEBUG
202                 hdlcdrv_add_bitbuffer_word(&s->bitbuf_hdlc, word);
203 #endif /* HDLCDRV_DEBUG */
204                 s->hdlcrx.bitstream >>= 16;
205                 s->hdlcrx.bitstream |= word << 16;
206                 s->hdlcrx.bitbuf >>= 16;
207                 s->hdlcrx.bitbuf |= word << 16;
208                 s->hdlcrx.numbits += 16;
209                 for(i = 15, mask1 = 0x1fc00, mask2 = 0x1fe00, mask3 = 0x0fc00,
210                     mask4 = 0x1f800, mask5 = 0xf800, mask6 = 0xffff; 
211                     i >= 0; 
212                     i--, mask1 <<= 1, mask2 <<= 1, mask3 <<= 1, mask4 <<= 1, 
213                     mask5 <<= 1, mask6 = (mask6 << 1) | 1) {
214                         if ((s->hdlcrx.bitstream & mask1) == mask1)
215                                 s->hdlcrx.rx_state = 0; /* abort received */
216                         else if ((s->hdlcrx.bitstream & mask2) == mask3) {
217                                 /* flag received */
218                                 if (s->hdlcrx.rx_state) {
219                                         hdlc_rx_add_bytes(s, s->hdlcrx.bitbuf 
220                                                           << (8+i),
221                                                           s->hdlcrx.numbits
222                                                           -8-i);
223                                         hdlc_rx_flag(dev, s);
224                                 }
225                                 s->hdlcrx.len = 0;
226                                 s->hdlcrx.bp = s->hdlcrx.buffer;
227                                 s->hdlcrx.rx_state = 1;
228                                 s->hdlcrx.numbits = i;
229                         } else if ((s->hdlcrx.bitstream & mask4) == mask5) {
230                                 /* stuffed bit */
231                                 s->hdlcrx.numbits--;
232                                 s->hdlcrx.bitbuf = (s->hdlcrx.bitbuf & (~mask6)) |
233                                         ((s->hdlcrx.bitbuf & mask6) << 1);
234                         }
235                 }
236                 s->hdlcrx.numbits -= hdlc_rx_add_bytes(s, s->hdlcrx.bitbuf,
237                                                        s->hdlcrx.numbits);
238         }
239         clear_bit(0, &s->hdlcrx.in_hdlc_rx);
240 }
241
242 /* ---------------------------------------------------------------------- */
243
244 static inline void do_kiss_params(struct hdlcdrv_state *s,
245                                   unsigned char *data, unsigned long len)
246 {
247
248 #ifdef KISS_VERBOSE
249 #define PKP(a,b) printk(KERN_INFO "hdlcdrv.c: channel params: " a "\n", b)
250 #else /* KISS_VERBOSE */              
251 #define PKP(a,b) 
252 #endif /* KISS_VERBOSE */             
253
254         if (len < 2)
255                 return;
256         switch(data[0]) {
257         case PARAM_TXDELAY:
258                 s->ch_params.tx_delay = data[1];
259                 PKP("TX delay = %ums", 10 * s->ch_params.tx_delay);
260                 break;
261         case PARAM_PERSIST:   
262                 s->ch_params.ppersist = data[1];
263                 PKP("p persistence = %u", s->ch_params.ppersist);
264                 break;
265         case PARAM_SLOTTIME:  
266                 s->ch_params.slottime = data[1];
267                 PKP("slot time = %ums", s->ch_params.slottime);
268                 break;
269         case PARAM_TXTAIL:    
270                 s->ch_params.tx_tail = data[1];
271                 PKP("TX tail = %ums", s->ch_params.tx_tail);
272                 break;
273         case PARAM_FULLDUP:   
274                 s->ch_params.fulldup = !!data[1];
275                 PKP("%s duplex", s->ch_params.fulldup ? "full" : "half");
276                 break;
277         default:
278                 break;
279         }
280 #undef PKP
281 }
282
283 /* ---------------------------------------------------------------------- */
284
285 void hdlcdrv_transmitter(struct net_device *dev, struct hdlcdrv_state *s)
286 {
287         unsigned int mask1, mask2, mask3;
288         int i;
289         struct sk_buff *skb;
290         int pkt_len;
291
292         if (!s || s->magic != HDLCDRV_MAGIC) 
293                 return;
294         if (test_and_set_bit(0, &s->hdlctx.in_hdlc_tx))
295                 return;
296         for (;;) {
297                 if (s->hdlctx.numbits >= 16) {
298                         if (hdlcdrv_hbuf_full(&s->hdlctx.hbuf)) {
299                                 clear_bit(0, &s->hdlctx.in_hdlc_tx);
300                                 return;
301                         }
302                         hdlcdrv_hbuf_put(&s->hdlctx.hbuf, s->hdlctx.bitbuf);
303                         s->hdlctx.bitbuf >>= 16;
304                         s->hdlctx.numbits -= 16;
305                 }
306                 switch (s->hdlctx.tx_state) {
307                 default:
308                         clear_bit(0, &s->hdlctx.in_hdlc_tx);
309                         return;
310                 case 0:
311                 case 1:
312                         if (s->hdlctx.numflags) {
313                                 s->hdlctx.numflags--;
314                                 s->hdlctx.bitbuf |= 
315                                         0x7e7e << s->hdlctx.numbits;
316                                 s->hdlctx.numbits += 16;
317                                 break;
318                         }
319                         if (s->hdlctx.tx_state == 1) {
320                                 clear_bit(0, &s->hdlctx.in_hdlc_tx);
321                                 return;
322                         }
323                         if (!(skb = s->skb)) {
324                                 int flgs = tenms_to_2flags(s, s->ch_params.tx_tail);
325                                 if (flgs < 2)
326                                         flgs = 2;
327                                 s->hdlctx.tx_state = 1;
328                                 s->hdlctx.numflags = flgs;
329                                 break;
330                         }
331                         s->skb = NULL;
332                         netif_wake_queue(dev);
333                         pkt_len = skb->len-1; /* strip KISS byte */
334                         if (pkt_len >= HDLCDRV_MAXFLEN || pkt_len < 2) {
335                                 s->hdlctx.tx_state = 0;
336                                 s->hdlctx.numflags = 1;
337                                 dev_kfree_skb_irq(skb);
338                                 break;
339                         }
340                         memcpy(s->hdlctx.buffer, skb->data+1, pkt_len);
341                         dev_kfree_skb_irq(skb);
342                         s->hdlctx.bp = s->hdlctx.buffer;
343                         append_crc_ccitt(s->hdlctx.buffer, pkt_len);
344                         s->hdlctx.len = pkt_len+2; /* the appended CRC */
345                         s->hdlctx.tx_state = 2;
346                         s->hdlctx.bitstream = 0;
347                         s->stats.tx_packets++;
348                         break;
349                 case 2:
350                         if (!s->hdlctx.len) {
351                                 s->hdlctx.tx_state = 0;
352                                 s->hdlctx.numflags = 1;
353                                 break;
354                         }
355                         s->hdlctx.len--;
356                         s->hdlctx.bitbuf |= *s->hdlctx.bp <<
357                                 s->hdlctx.numbits;
358                         s->hdlctx.bitstream >>= 8;
359                         s->hdlctx.bitstream |= (*s->hdlctx.bp++) << 16;
360                         mask1 = 0x1f000;
361                         mask2 = 0x10000;
362                         mask3 = 0xffffffff >> (31-s->hdlctx.numbits);
363                         s->hdlctx.numbits += 8;
364                         for(i = 0; i < 8; i++, mask1 <<= 1, mask2 <<= 1, 
365                             mask3 = (mask3 << 1) | 1) {
366                                 if ((s->hdlctx.bitstream & mask1) != mask1) 
367                                         continue;
368                                 s->hdlctx.bitstream &= ~mask2;
369                                 s->hdlctx.bitbuf = 
370                                         (s->hdlctx.bitbuf & mask3) |
371                                                 ((s->hdlctx.bitbuf & 
372                                                  (~mask3)) << 1);
373                                 s->hdlctx.numbits++;
374                                 mask3 = (mask3 << 1) | 1;
375                         }
376                         break;
377                 }
378         }
379 }
380
381 /* ---------------------------------------------------------------------- */
382
383 static void start_tx(struct net_device *dev, struct hdlcdrv_state *s)
384 {
385         s->hdlctx.tx_state = 0;
386         s->hdlctx.numflags = tenms_to_2flags(s, s->ch_params.tx_delay);
387         s->hdlctx.bitbuf = s->hdlctx.bitstream = s->hdlctx.numbits = 0;
388         hdlcdrv_transmitter(dev, s);
389         s->hdlctx.ptt = 1;
390         s->ptt_keyed++;
391 }
392
393 /* ---------------------------------------------------------------------- */
394
395 static unsigned short random_seed;
396
397 static inline unsigned short random_num(void)
398 {
399         random_seed = 28629 * random_seed + 157;
400         return random_seed;
401 }
402
403 /* ---------------------------------------------------------------------- */
404
405 void hdlcdrv_arbitrate(struct net_device *dev, struct hdlcdrv_state *s)
406 {
407         if (!s || s->magic != HDLCDRV_MAGIC || s->hdlctx.ptt || !s->skb) 
408                 return;
409         if (s->ch_params.fulldup) {
410                 start_tx(dev, s);
411                 return;
412         }
413         if (s->hdlcrx.dcd) {
414                 s->hdlctx.slotcnt = s->ch_params.slottime;
415                 return;
416         }
417         if ((--s->hdlctx.slotcnt) > 0)
418                 return;
419         s->hdlctx.slotcnt = s->ch_params.slottime;
420         if ((random_num() % 256) > s->ch_params.ppersist)
421                 return;
422         start_tx(dev, s);
423 }
424
425 /* --------------------------------------------------------------------- */
426 /*
427  * ===================== network driver interface =========================
428  */
429
430 static int hdlcdrv_send_packet(struct sk_buff *skb, struct net_device *dev)
431 {
432         struct hdlcdrv_state *sm = netdev_priv(dev);
433
434         if (skb->data[0] != 0) {
435                 do_kiss_params(sm, skb->data, skb->len);
436                 dev_kfree_skb(skb);
437                 return 0;
438         }
439         if (sm->skb)
440                 return -1;
441         netif_stop_queue(dev);
442         sm->skb = skb;
443         return 0;
444 }
445
446 /* --------------------------------------------------------------------- */
447
448 static int hdlcdrv_set_mac_address(struct net_device *dev, void *addr)
449 {
450         struct sockaddr *sa = (struct sockaddr *)addr;
451
452         /* addr is an AX.25 shifted ASCII mac address */
453         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); 
454         return 0;                                         
455 }
456
457 /* --------------------------------------------------------------------- */
458
459 static struct net_device_stats *hdlcdrv_get_stats(struct net_device *dev)
460 {
461         struct hdlcdrv_state *sm = netdev_priv(dev);
462
463         /* 
464          * Get the current statistics.  This may be called with the
465          * card open or closed. 
466          */
467         return &sm->stats;
468 }
469
470 /* --------------------------------------------------------------------- */
471 /*
472  * Open/initialize the board. This is called (in the current kernel)
473  * sometime after booting when the 'ifconfig' program is run.
474  *
475  * This routine should set everything up anew at each open, even
476  * registers that "should" only need to be set once at boot, so that
477  * there is non-reboot way to recover if something goes wrong.
478  */
479
480 static int hdlcdrv_open(struct net_device *dev)
481 {
482         struct hdlcdrv_state *s = netdev_priv(dev);
483         int i;
484
485         if (!s->ops || !s->ops->open)
486                 return -ENODEV;
487
488         /*
489          * initialise some variables
490          */
491         s->opened = 1;
492         s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
493         s->hdlcrx.in_hdlc_rx = 0;
494         s->hdlcrx.rx_state = 0;
495         
496         s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
497         s->hdlctx.in_hdlc_tx = 0;
498         s->hdlctx.tx_state = 1;
499         s->hdlctx.numflags = 0;
500         s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
501         s->hdlctx.ptt = 0;
502         s->hdlctx.slotcnt = s->ch_params.slottime;
503         s->hdlctx.calibrate = 0;
504
505         i = s->ops->open(dev);
506         if (i)
507                 return i;
508         netif_start_queue(dev);
509         return 0;
510 }
511
512 /* --------------------------------------------------------------------- */
513 /* 
514  * The inverse routine to hdlcdrv_open(). 
515  */
516
517 static int hdlcdrv_close(struct net_device *dev)
518 {
519         struct hdlcdrv_state *s = netdev_priv(dev);
520         int i = 0;
521
522         netif_stop_queue(dev);
523
524         if (s->ops && s->ops->close)
525                 i = s->ops->close(dev);
526         if (s->skb)
527                 dev_kfree_skb(s->skb);
528         s->skb = NULL;
529         s->opened = 0;
530         return i;
531 }
532
533 /* --------------------------------------------------------------------- */
534
535 static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
536 {
537         struct hdlcdrv_state *s = netdev_priv(dev);
538         struct hdlcdrv_ioctl bi;
539
540         if (cmd != SIOCDEVPRIVATE) {
541                 if (s->ops && s->ops->ioctl)
542                         return s->ops->ioctl(dev, ifr, &bi, cmd);
543                 return -ENOIOCTLCMD;
544         }
545         if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
546                 return -EFAULT;
547
548         switch (bi.cmd) {
549         default:
550                 if (s->ops && s->ops->ioctl)
551                         return s->ops->ioctl(dev, ifr, &bi, cmd);
552                 return -ENOIOCTLCMD;
553
554         case HDLCDRVCTL_GETCHANNELPAR:
555                 bi.data.cp.tx_delay = s->ch_params.tx_delay;
556                 bi.data.cp.tx_tail = s->ch_params.tx_tail;
557                 bi.data.cp.slottime = s->ch_params.slottime;
558                 bi.data.cp.ppersist = s->ch_params.ppersist;
559                 bi.data.cp.fulldup = s->ch_params.fulldup;
560                 break;
561
562         case HDLCDRVCTL_SETCHANNELPAR:
563                 if (!capable(CAP_NET_ADMIN))
564                         return -EACCES;
565                 s->ch_params.tx_delay = bi.data.cp.tx_delay;
566                 s->ch_params.tx_tail = bi.data.cp.tx_tail;
567                 s->ch_params.slottime = bi.data.cp.slottime;
568                 s->ch_params.ppersist = bi.data.cp.ppersist;
569                 s->ch_params.fulldup = bi.data.cp.fulldup;
570                 s->hdlctx.slotcnt = 1;
571                 return 0;
572                 
573         case HDLCDRVCTL_GETMODEMPAR:
574                 bi.data.mp.iobase = dev->base_addr;
575                 bi.data.mp.irq = dev->irq;
576                 bi.data.mp.dma = dev->dma;
577                 bi.data.mp.dma2 = s->ptt_out.dma2;
578                 bi.data.mp.seriobase = s->ptt_out.seriobase;
579                 bi.data.mp.pariobase = s->ptt_out.pariobase;
580                 bi.data.mp.midiiobase = s->ptt_out.midiiobase;
581                 break;
582
583         case HDLCDRVCTL_SETMODEMPAR:
584                 if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
585                         return -EACCES;
586                 dev->base_addr = bi.data.mp.iobase;
587                 dev->irq = bi.data.mp.irq;
588                 dev->dma = bi.data.mp.dma;
589                 s->ptt_out.dma2 = bi.data.mp.dma2;
590                 s->ptt_out.seriobase = bi.data.mp.seriobase;
591                 s->ptt_out.pariobase = bi.data.mp.pariobase;
592                 s->ptt_out.midiiobase = bi.data.mp.midiiobase;
593                 return 0;       
594         
595         case HDLCDRVCTL_GETSTAT:
596                 bi.data.cs.ptt = hdlcdrv_ptt(s);
597                 bi.data.cs.dcd = s->hdlcrx.dcd;
598                 bi.data.cs.ptt_keyed = s->ptt_keyed;
599                 bi.data.cs.tx_packets = s->stats.tx_packets;
600                 bi.data.cs.tx_errors = s->stats.tx_errors;
601                 bi.data.cs.rx_packets = s->stats.rx_packets;
602                 bi.data.cs.rx_errors = s->stats.rx_errors;
603                 break;          
604
605         case HDLCDRVCTL_OLDGETSTAT:
606                 bi.data.ocs.ptt = hdlcdrv_ptt(s);
607                 bi.data.ocs.dcd = s->hdlcrx.dcd;
608                 bi.data.ocs.ptt_keyed = s->ptt_keyed;
609                 break;          
610
611         case HDLCDRVCTL_CALIBRATE:
612                 if(!capable(CAP_SYS_RAWIO))
613                         return -EPERM;
614                 s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
615                 return 0;
616
617         case HDLCDRVCTL_GETSAMPLES:
618 #ifndef HDLCDRV_DEBUG
619                 return -EPERM;
620 #else /* HDLCDRV_DEBUG */
621                 if (s->bitbuf_channel.rd == s->bitbuf_channel.wr) 
622                         return -EAGAIN;
623                 bi.data.bits = 
624                         s->bitbuf_channel.buffer[s->bitbuf_channel.rd];
625                 s->bitbuf_channel.rd = (s->bitbuf_channel.rd+1) %
626                         sizeof(s->bitbuf_channel.buffer);
627                 break;
628 #endif /* HDLCDRV_DEBUG */
629                                 
630         case HDLCDRVCTL_GETBITS:
631 #ifndef HDLCDRV_DEBUG
632                 return -EPERM;
633 #else /* HDLCDRV_DEBUG */
634                 if (s->bitbuf_hdlc.rd == s->bitbuf_hdlc.wr) 
635                         return -EAGAIN;
636                 bi.data.bits = 
637                         s->bitbuf_hdlc.buffer[s->bitbuf_hdlc.rd];
638                 s->bitbuf_hdlc.rd = (s->bitbuf_hdlc.rd+1) %
639                         sizeof(s->bitbuf_hdlc.buffer);
640                 break;          
641 #endif /* HDLCDRV_DEBUG */
642
643         case HDLCDRVCTL_DRIVERNAME:
644                 if (s->ops && s->ops->drvname) {
645                         strncpy(bi.data.drivername, s->ops->drvname, 
646                                 sizeof(bi.data.drivername));
647                         break;
648                 }
649                 bi.data.drivername[0] = '\0';
650                 break;
651                 
652         }
653         if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
654                 return -EFAULT;
655         return 0;
656
657 }
658
659 /* --------------------------------------------------------------------- */
660
661 /*
662  * Initialize fields in hdlcdrv
663  */
664 static void hdlcdrv_setup(struct net_device *dev)
665 {
666         static const struct hdlcdrv_channel_params dflt_ch_params = { 
667                 20, 2, 10, 40, 0 
668         };
669         struct hdlcdrv_state *s = netdev_priv(dev);
670
671         /*
672          * initialize the hdlcdrv_state struct
673          */
674         s->ch_params = dflt_ch_params;
675         s->ptt_keyed = 0;
676
677         spin_lock_init(&s->hdlcrx.hbuf.lock);
678         s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
679         s->hdlcrx.in_hdlc_rx = 0;
680         s->hdlcrx.rx_state = 0;
681         
682         spin_lock_init(&s->hdlctx.hbuf.lock);
683         s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
684         s->hdlctx.in_hdlc_tx = 0;
685         s->hdlctx.tx_state = 1;
686         s->hdlctx.numflags = 0;
687         s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
688         s->hdlctx.ptt = 0;
689         s->hdlctx.slotcnt = s->ch_params.slottime;
690         s->hdlctx.calibrate = 0;
691
692 #ifdef HDLCDRV_DEBUG
693         s->bitbuf_channel.rd = s->bitbuf_channel.wr = 0;
694         s->bitbuf_channel.shreg = 0x80;
695
696         s->bitbuf_hdlc.rd = s->bitbuf_hdlc.wr = 0;
697         s->bitbuf_hdlc.shreg = 0x80;
698 #endif /* HDLCDRV_DEBUG */
699
700         /*
701          * initialize the device struct
702          */
703         dev->open = hdlcdrv_open;
704         dev->stop = hdlcdrv_close;
705         dev->do_ioctl = hdlcdrv_ioctl;
706         dev->hard_start_xmit = hdlcdrv_send_packet;
707         dev->get_stats = hdlcdrv_get_stats;
708
709         /* Fill in the fields of the device structure */
710
711         s->skb = NULL;
712         
713 #if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE)
714         dev->hard_header = ax25_encapsulate;
715         dev->rebuild_header = ax25_rebuild_header;
716 #else /* CONFIG_AX25 || CONFIG_AX25_MODULE */
717         dev->hard_header = NULL;
718         dev->rebuild_header = NULL;
719 #endif /* CONFIG_AX25 || CONFIG_AX25_MODULE */
720         dev->set_mac_address = hdlcdrv_set_mac_address;
721         
722         dev->type = ARPHRD_AX25;           /* AF_AX25 device */
723         dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
724         dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
725         dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
726         memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN);
727         memcpy(dev->dev_addr, ax25_nocall, AX25_ADDR_LEN);
728         dev->tx_queue_len = 16;
729 }
730
731 /* --------------------------------------------------------------------- */
732 struct net_device *hdlcdrv_register(const struct hdlcdrv_ops *ops,
733                                     unsigned int privsize, const char *ifname,
734                                     unsigned int baseaddr, unsigned int irq, 
735                                     unsigned int dma) 
736 {
737         struct net_device *dev;
738         struct hdlcdrv_state *s;
739         int err;
740
741         BUG_ON(ops == NULL);
742
743         if (privsize < sizeof(struct hdlcdrv_state))
744                 privsize = sizeof(struct hdlcdrv_state);
745
746         dev = alloc_netdev(privsize, ifname, hdlcdrv_setup);
747         if (!dev)
748                 return ERR_PTR(-ENOMEM);
749
750         /*
751          * initialize part of the hdlcdrv_state struct
752          */
753         s = netdev_priv(dev);
754         s->magic = HDLCDRV_MAGIC;
755         s->ops = ops;
756         dev->base_addr = baseaddr;
757         dev->irq = irq;
758         dev->dma = dma;
759
760         err = register_netdev(dev);
761         if (err < 0) {
762                 printk(KERN_WARNING "hdlcdrv: cannot register net "
763                        "device %s\n", dev->name);
764                 free_netdev(dev);
765                 dev = ERR_PTR(err);
766         }
767         return dev;
768 }
769
770 /* --------------------------------------------------------------------- */
771
772 void hdlcdrv_unregister(struct net_device *dev) 
773 {
774         struct hdlcdrv_state *s = netdev_priv(dev);
775
776         BUG_ON(s->magic != HDLCDRV_MAGIC);
777
778         if (s->opened && s->ops->close)
779                 s->ops->close(dev);
780         unregister_netdev(dev);
781         
782         free_netdev(dev);
783 }
784
785 /* --------------------------------------------------------------------- */
786
787 EXPORT_SYMBOL(hdlcdrv_receiver);
788 EXPORT_SYMBOL(hdlcdrv_transmitter);
789 EXPORT_SYMBOL(hdlcdrv_arbitrate);
790 EXPORT_SYMBOL(hdlcdrv_register);
791 EXPORT_SYMBOL(hdlcdrv_unregister);
792
793 /* --------------------------------------------------------------------- */
794
795 static int __init hdlcdrv_init_driver(void)
796 {
797         printk(KERN_INFO "hdlcdrv: (C) 1996-2000 Thomas Sailer HB9JNX/AE4WA\n");
798         printk(KERN_INFO "hdlcdrv: version 0.8 compiled " __TIME__ " " __DATE__ "\n");
799         return 0;
800 }
801
802 /* --------------------------------------------------------------------- */
803
804 static void __exit hdlcdrv_cleanup_driver(void)
805 {
806         printk(KERN_INFO "hdlcdrv: cleanup\n");
807 }
808
809 /* --------------------------------------------------------------------- */
810
811 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
812 MODULE_DESCRIPTION("Packet Radio network interface HDLC encoder/decoder");
813 MODULE_LICENSE("GPL");
814 module_init(hdlcdrv_init_driver);
815 module_exit(hdlcdrv_cleanup_driver);
816
817 /* --------------------------------------------------------------------- */