Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6] / 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         s->stats.rx_packets++;
166 }
167
168 void hdlcdrv_receiver(struct net_device *dev, struct hdlcdrv_state *s)
169 {
170         int i;
171         unsigned int mask1, mask2, mask3, mask4, mask5, mask6, word;
172         
173         if (!s || s->magic != HDLCDRV_MAGIC) 
174                 return;
175         if (test_and_set_bit(0, &s->hdlcrx.in_hdlc_rx))
176                 return;
177
178         while (!hdlcdrv_hbuf_empty(&s->hdlcrx.hbuf)) {
179                 word = hdlcdrv_hbuf_get(&s->hdlcrx.hbuf);       
180
181 #ifdef HDLCDRV_DEBUG
182                 hdlcdrv_add_bitbuffer_word(&s->bitbuf_hdlc, word);
183 #endif /* HDLCDRV_DEBUG */
184                 s->hdlcrx.bitstream >>= 16;
185                 s->hdlcrx.bitstream |= word << 16;
186                 s->hdlcrx.bitbuf >>= 16;
187                 s->hdlcrx.bitbuf |= word << 16;
188                 s->hdlcrx.numbits += 16;
189                 for(i = 15, mask1 = 0x1fc00, mask2 = 0x1fe00, mask3 = 0x0fc00,
190                     mask4 = 0x1f800, mask5 = 0xf800, mask6 = 0xffff; 
191                     i >= 0; 
192                     i--, mask1 <<= 1, mask2 <<= 1, mask3 <<= 1, mask4 <<= 1, 
193                     mask5 <<= 1, mask6 = (mask6 << 1) | 1) {
194                         if ((s->hdlcrx.bitstream & mask1) == mask1)
195                                 s->hdlcrx.rx_state = 0; /* abort received */
196                         else if ((s->hdlcrx.bitstream & mask2) == mask3) {
197                                 /* flag received */
198                                 if (s->hdlcrx.rx_state) {
199                                         hdlc_rx_add_bytes(s, s->hdlcrx.bitbuf 
200                                                           << (8+i),
201                                                           s->hdlcrx.numbits
202                                                           -8-i);
203                                         hdlc_rx_flag(dev, s);
204                                 }
205                                 s->hdlcrx.len = 0;
206                                 s->hdlcrx.bp = s->hdlcrx.buffer;
207                                 s->hdlcrx.rx_state = 1;
208                                 s->hdlcrx.numbits = i;
209                         } else if ((s->hdlcrx.bitstream & mask4) == mask5) {
210                                 /* stuffed bit */
211                                 s->hdlcrx.numbits--;
212                                 s->hdlcrx.bitbuf = (s->hdlcrx.bitbuf & (~mask6)) |
213                                         ((s->hdlcrx.bitbuf & mask6) << 1);
214                         }
215                 }
216                 s->hdlcrx.numbits -= hdlc_rx_add_bytes(s, s->hdlcrx.bitbuf,
217                                                        s->hdlcrx.numbits);
218         }
219         clear_bit(0, &s->hdlcrx.in_hdlc_rx);
220 }
221
222 /* ---------------------------------------------------------------------- */
223
224 static inline void do_kiss_params(struct hdlcdrv_state *s,
225                                   unsigned char *data, unsigned long len)
226 {
227
228 #ifdef KISS_VERBOSE
229 #define PKP(a,b) printk(KERN_INFO "hdlcdrv.c: channel params: " a "\n", b)
230 #else /* KISS_VERBOSE */              
231 #define PKP(a,b) 
232 #endif /* KISS_VERBOSE */             
233
234         if (len < 2)
235                 return;
236         switch(data[0]) {
237         case PARAM_TXDELAY:
238                 s->ch_params.tx_delay = data[1];
239                 PKP("TX delay = %ums", 10 * s->ch_params.tx_delay);
240                 break;
241         case PARAM_PERSIST:   
242                 s->ch_params.ppersist = data[1];
243                 PKP("p persistence = %u", s->ch_params.ppersist);
244                 break;
245         case PARAM_SLOTTIME:  
246                 s->ch_params.slottime = data[1];
247                 PKP("slot time = %ums", s->ch_params.slottime);
248                 break;
249         case PARAM_TXTAIL:    
250                 s->ch_params.tx_tail = data[1];
251                 PKP("TX tail = %ums", s->ch_params.tx_tail);
252                 break;
253         case PARAM_FULLDUP:   
254                 s->ch_params.fulldup = !!data[1];
255                 PKP("%s duplex", s->ch_params.fulldup ? "full" : "half");
256                 break;
257         default:
258                 break;
259         }
260 #undef PKP
261 }
262
263 /* ---------------------------------------------------------------------- */
264
265 void hdlcdrv_transmitter(struct net_device *dev, struct hdlcdrv_state *s)
266 {
267         unsigned int mask1, mask2, mask3;
268         int i;
269         struct sk_buff *skb;
270         int pkt_len;
271
272         if (!s || s->magic != HDLCDRV_MAGIC) 
273                 return;
274         if (test_and_set_bit(0, &s->hdlctx.in_hdlc_tx))
275                 return;
276         for (;;) {
277                 if (s->hdlctx.numbits >= 16) {
278                         if (hdlcdrv_hbuf_full(&s->hdlctx.hbuf)) {
279                                 clear_bit(0, &s->hdlctx.in_hdlc_tx);
280                                 return;
281                         }
282                         hdlcdrv_hbuf_put(&s->hdlctx.hbuf, s->hdlctx.bitbuf);
283                         s->hdlctx.bitbuf >>= 16;
284                         s->hdlctx.numbits -= 16;
285                 }
286                 switch (s->hdlctx.tx_state) {
287                 default:
288                         clear_bit(0, &s->hdlctx.in_hdlc_tx);
289                         return;
290                 case 0:
291                 case 1:
292                         if (s->hdlctx.numflags) {
293                                 s->hdlctx.numflags--;
294                                 s->hdlctx.bitbuf |= 
295                                         0x7e7e << s->hdlctx.numbits;
296                                 s->hdlctx.numbits += 16;
297                                 break;
298                         }
299                         if (s->hdlctx.tx_state == 1) {
300                                 clear_bit(0, &s->hdlctx.in_hdlc_tx);
301                                 return;
302                         }
303                         if (!(skb = s->skb)) {
304                                 int flgs = tenms_to_2flags(s, s->ch_params.tx_tail);
305                                 if (flgs < 2)
306                                         flgs = 2;
307                                 s->hdlctx.tx_state = 1;
308                                 s->hdlctx.numflags = flgs;
309                                 break;
310                         }
311                         s->skb = NULL;
312                         netif_wake_queue(dev);
313                         pkt_len = skb->len-1; /* strip KISS byte */
314                         if (pkt_len >= HDLCDRV_MAXFLEN || pkt_len < 2) {
315                                 s->hdlctx.tx_state = 0;
316                                 s->hdlctx.numflags = 1;
317                                 dev_kfree_skb_irq(skb);
318                                 break;
319                         }
320                         skb_copy_from_linear_data_offset(skb, 1,
321                                                          s->hdlctx.buffer,
322                                                          pkt_len);
323                         dev_kfree_skb_irq(skb);
324                         s->hdlctx.bp = s->hdlctx.buffer;
325                         append_crc_ccitt(s->hdlctx.buffer, pkt_len);
326                         s->hdlctx.len = pkt_len+2; /* the appended CRC */
327                         s->hdlctx.tx_state = 2;
328                         s->hdlctx.bitstream = 0;
329                         s->stats.tx_packets++;
330                         break;
331                 case 2:
332                         if (!s->hdlctx.len) {
333                                 s->hdlctx.tx_state = 0;
334                                 s->hdlctx.numflags = 1;
335                                 break;
336                         }
337                         s->hdlctx.len--;
338                         s->hdlctx.bitbuf |= *s->hdlctx.bp <<
339                                 s->hdlctx.numbits;
340                         s->hdlctx.bitstream >>= 8;
341                         s->hdlctx.bitstream |= (*s->hdlctx.bp++) << 16;
342                         mask1 = 0x1f000;
343                         mask2 = 0x10000;
344                         mask3 = 0xffffffff >> (31-s->hdlctx.numbits);
345                         s->hdlctx.numbits += 8;
346                         for(i = 0; i < 8; i++, mask1 <<= 1, mask2 <<= 1, 
347                             mask3 = (mask3 << 1) | 1) {
348                                 if ((s->hdlctx.bitstream & mask1) != mask1) 
349                                         continue;
350                                 s->hdlctx.bitstream &= ~mask2;
351                                 s->hdlctx.bitbuf = 
352                                         (s->hdlctx.bitbuf & mask3) |
353                                                 ((s->hdlctx.bitbuf & 
354                                                  (~mask3)) << 1);
355                                 s->hdlctx.numbits++;
356                                 mask3 = (mask3 << 1) | 1;
357                         }
358                         break;
359                 }
360         }
361 }
362
363 /* ---------------------------------------------------------------------- */
364
365 static void start_tx(struct net_device *dev, struct hdlcdrv_state *s)
366 {
367         s->hdlctx.tx_state = 0;
368         s->hdlctx.numflags = tenms_to_2flags(s, s->ch_params.tx_delay);
369         s->hdlctx.bitbuf = s->hdlctx.bitstream = s->hdlctx.numbits = 0;
370         hdlcdrv_transmitter(dev, s);
371         s->hdlctx.ptt = 1;
372         s->ptt_keyed++;
373 }
374
375 /* ---------------------------------------------------------------------- */
376
377 void hdlcdrv_arbitrate(struct net_device *dev, struct hdlcdrv_state *s)
378 {
379         if (!s || s->magic != HDLCDRV_MAGIC || s->hdlctx.ptt || !s->skb) 
380                 return;
381         if (s->ch_params.fulldup) {
382                 start_tx(dev, s);
383                 return;
384         }
385         if (s->hdlcrx.dcd) {
386                 s->hdlctx.slotcnt = s->ch_params.slottime;
387                 return;
388         }
389         if ((--s->hdlctx.slotcnt) > 0)
390                 return;
391         s->hdlctx.slotcnt = s->ch_params.slottime;
392         if ((random32() % 256) > s->ch_params.ppersist)
393                 return;
394         start_tx(dev, s);
395 }
396
397 /* --------------------------------------------------------------------- */
398 /*
399  * ===================== network driver interface =========================
400  */
401
402 static int hdlcdrv_send_packet(struct sk_buff *skb, struct net_device *dev)
403 {
404         struct hdlcdrv_state *sm = netdev_priv(dev);
405
406         if (skb->data[0] != 0) {
407                 do_kiss_params(sm, skb->data, skb->len);
408                 dev_kfree_skb(skb);
409                 return 0;
410         }
411         if (sm->skb)
412                 return -1;
413         netif_stop_queue(dev);
414         sm->skb = skb;
415         return 0;
416 }
417
418 /* --------------------------------------------------------------------- */
419
420 static int hdlcdrv_set_mac_address(struct net_device *dev, void *addr)
421 {
422         struct sockaddr *sa = (struct sockaddr *)addr;
423
424         /* addr is an AX.25 shifted ASCII mac address */
425         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); 
426         return 0;                                         
427 }
428
429 /* --------------------------------------------------------------------- */
430
431 static struct net_device_stats *hdlcdrv_get_stats(struct net_device *dev)
432 {
433         struct hdlcdrv_state *sm = netdev_priv(dev);
434
435         /* 
436          * Get the current statistics.  This may be called with the
437          * card open or closed. 
438          */
439         return &sm->stats;
440 }
441
442 /* --------------------------------------------------------------------- */
443 /*
444  * Open/initialize the board. This is called (in the current kernel)
445  * sometime after booting when the 'ifconfig' program is run.
446  *
447  * This routine should set everything up anew at each open, even
448  * registers that "should" only need to be set once at boot, so that
449  * there is non-reboot way to recover if something goes wrong.
450  */
451
452 static int hdlcdrv_open(struct net_device *dev)
453 {
454         struct hdlcdrv_state *s = netdev_priv(dev);
455         int i;
456
457         if (!s->ops || !s->ops->open)
458                 return -ENODEV;
459
460         /*
461          * initialise some variables
462          */
463         s->opened = 1;
464         s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
465         s->hdlcrx.in_hdlc_rx = 0;
466         s->hdlcrx.rx_state = 0;
467         
468         s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
469         s->hdlctx.in_hdlc_tx = 0;
470         s->hdlctx.tx_state = 1;
471         s->hdlctx.numflags = 0;
472         s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
473         s->hdlctx.ptt = 0;
474         s->hdlctx.slotcnt = s->ch_params.slottime;
475         s->hdlctx.calibrate = 0;
476
477         i = s->ops->open(dev);
478         if (i)
479                 return i;
480         netif_start_queue(dev);
481         return 0;
482 }
483
484 /* --------------------------------------------------------------------- */
485 /* 
486  * The inverse routine to hdlcdrv_open(). 
487  */
488
489 static int hdlcdrv_close(struct net_device *dev)
490 {
491         struct hdlcdrv_state *s = netdev_priv(dev);
492         int i = 0;
493
494         netif_stop_queue(dev);
495
496         if (s->ops && s->ops->close)
497                 i = s->ops->close(dev);
498         if (s->skb)
499                 dev_kfree_skb(s->skb);
500         s->skb = NULL;
501         s->opened = 0;
502         return i;
503 }
504
505 /* --------------------------------------------------------------------- */
506
507 static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
508 {
509         struct hdlcdrv_state *s = netdev_priv(dev);
510         struct hdlcdrv_ioctl bi;
511
512         if (cmd != SIOCDEVPRIVATE) {
513                 if (s->ops && s->ops->ioctl)
514                         return s->ops->ioctl(dev, ifr, &bi, cmd);
515                 return -ENOIOCTLCMD;
516         }
517         if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
518                 return -EFAULT;
519
520         switch (bi.cmd) {
521         default:
522                 if (s->ops && s->ops->ioctl)
523                         return s->ops->ioctl(dev, ifr, &bi, cmd);
524                 return -ENOIOCTLCMD;
525
526         case HDLCDRVCTL_GETCHANNELPAR:
527                 bi.data.cp.tx_delay = s->ch_params.tx_delay;
528                 bi.data.cp.tx_tail = s->ch_params.tx_tail;
529                 bi.data.cp.slottime = s->ch_params.slottime;
530                 bi.data.cp.ppersist = s->ch_params.ppersist;
531                 bi.data.cp.fulldup = s->ch_params.fulldup;
532                 break;
533
534         case HDLCDRVCTL_SETCHANNELPAR:
535                 if (!capable(CAP_NET_ADMIN))
536                         return -EACCES;
537                 s->ch_params.tx_delay = bi.data.cp.tx_delay;
538                 s->ch_params.tx_tail = bi.data.cp.tx_tail;
539                 s->ch_params.slottime = bi.data.cp.slottime;
540                 s->ch_params.ppersist = bi.data.cp.ppersist;
541                 s->ch_params.fulldup = bi.data.cp.fulldup;
542                 s->hdlctx.slotcnt = 1;
543                 return 0;
544                 
545         case HDLCDRVCTL_GETMODEMPAR:
546                 bi.data.mp.iobase = dev->base_addr;
547                 bi.data.mp.irq = dev->irq;
548                 bi.data.mp.dma = dev->dma;
549                 bi.data.mp.dma2 = s->ptt_out.dma2;
550                 bi.data.mp.seriobase = s->ptt_out.seriobase;
551                 bi.data.mp.pariobase = s->ptt_out.pariobase;
552                 bi.data.mp.midiiobase = s->ptt_out.midiiobase;
553                 break;
554
555         case HDLCDRVCTL_SETMODEMPAR:
556                 if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
557                         return -EACCES;
558                 dev->base_addr = bi.data.mp.iobase;
559                 dev->irq = bi.data.mp.irq;
560                 dev->dma = bi.data.mp.dma;
561                 s->ptt_out.dma2 = bi.data.mp.dma2;
562                 s->ptt_out.seriobase = bi.data.mp.seriobase;
563                 s->ptt_out.pariobase = bi.data.mp.pariobase;
564                 s->ptt_out.midiiobase = bi.data.mp.midiiobase;
565                 return 0;       
566         
567         case HDLCDRVCTL_GETSTAT:
568                 bi.data.cs.ptt = hdlcdrv_ptt(s);
569                 bi.data.cs.dcd = s->hdlcrx.dcd;
570                 bi.data.cs.ptt_keyed = s->ptt_keyed;
571                 bi.data.cs.tx_packets = s->stats.tx_packets;
572                 bi.data.cs.tx_errors = s->stats.tx_errors;
573                 bi.data.cs.rx_packets = s->stats.rx_packets;
574                 bi.data.cs.rx_errors = s->stats.rx_errors;
575                 break;          
576
577         case HDLCDRVCTL_OLDGETSTAT:
578                 bi.data.ocs.ptt = hdlcdrv_ptt(s);
579                 bi.data.ocs.dcd = s->hdlcrx.dcd;
580                 bi.data.ocs.ptt_keyed = s->ptt_keyed;
581                 break;          
582
583         case HDLCDRVCTL_CALIBRATE:
584                 if(!capable(CAP_SYS_RAWIO))
585                         return -EPERM;
586                 s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
587                 return 0;
588
589         case HDLCDRVCTL_GETSAMPLES:
590 #ifndef HDLCDRV_DEBUG
591                 return -EPERM;
592 #else /* HDLCDRV_DEBUG */
593                 if (s->bitbuf_channel.rd == s->bitbuf_channel.wr) 
594                         return -EAGAIN;
595                 bi.data.bits = 
596                         s->bitbuf_channel.buffer[s->bitbuf_channel.rd];
597                 s->bitbuf_channel.rd = (s->bitbuf_channel.rd+1) %
598                         sizeof(s->bitbuf_channel.buffer);
599                 break;
600 #endif /* HDLCDRV_DEBUG */
601                                 
602         case HDLCDRVCTL_GETBITS:
603 #ifndef HDLCDRV_DEBUG
604                 return -EPERM;
605 #else /* HDLCDRV_DEBUG */
606                 if (s->bitbuf_hdlc.rd == s->bitbuf_hdlc.wr) 
607                         return -EAGAIN;
608                 bi.data.bits = 
609                         s->bitbuf_hdlc.buffer[s->bitbuf_hdlc.rd];
610                 s->bitbuf_hdlc.rd = (s->bitbuf_hdlc.rd+1) %
611                         sizeof(s->bitbuf_hdlc.buffer);
612                 break;          
613 #endif /* HDLCDRV_DEBUG */
614
615         case HDLCDRVCTL_DRIVERNAME:
616                 if (s->ops && s->ops->drvname) {
617                         strncpy(bi.data.drivername, s->ops->drvname, 
618                                 sizeof(bi.data.drivername));
619                         break;
620                 }
621                 bi.data.drivername[0] = '\0';
622                 break;
623                 
624         }
625         if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
626                 return -EFAULT;
627         return 0;
628
629 }
630
631 /* --------------------------------------------------------------------- */
632
633 /*
634  * Initialize fields in hdlcdrv
635  */
636 static void hdlcdrv_setup(struct net_device *dev)
637 {
638         static const struct hdlcdrv_channel_params dflt_ch_params = { 
639                 20, 2, 10, 40, 0 
640         };
641         struct hdlcdrv_state *s = netdev_priv(dev);
642
643         /*
644          * initialize the hdlcdrv_state struct
645          */
646         s->ch_params = dflt_ch_params;
647         s->ptt_keyed = 0;
648
649         spin_lock_init(&s->hdlcrx.hbuf.lock);
650         s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
651         s->hdlcrx.in_hdlc_rx = 0;
652         s->hdlcrx.rx_state = 0;
653         
654         spin_lock_init(&s->hdlctx.hbuf.lock);
655         s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
656         s->hdlctx.in_hdlc_tx = 0;
657         s->hdlctx.tx_state = 1;
658         s->hdlctx.numflags = 0;
659         s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
660         s->hdlctx.ptt = 0;
661         s->hdlctx.slotcnt = s->ch_params.slottime;
662         s->hdlctx.calibrate = 0;
663
664 #ifdef HDLCDRV_DEBUG
665         s->bitbuf_channel.rd = s->bitbuf_channel.wr = 0;
666         s->bitbuf_channel.shreg = 0x80;
667
668         s->bitbuf_hdlc.rd = s->bitbuf_hdlc.wr = 0;
669         s->bitbuf_hdlc.shreg = 0x80;
670 #endif /* HDLCDRV_DEBUG */
671
672         /*
673          * initialize the device struct
674          */
675         dev->open = hdlcdrv_open;
676         dev->stop = hdlcdrv_close;
677         dev->do_ioctl = hdlcdrv_ioctl;
678         dev->hard_start_xmit = hdlcdrv_send_packet;
679         dev->get_stats = hdlcdrv_get_stats;
680
681         /* Fill in the fields of the device structure */
682
683         s->skb = NULL;
684         
685         dev->header_ops = &ax25_header_ops;
686         dev->set_mac_address = hdlcdrv_set_mac_address;
687         
688         dev->type = ARPHRD_AX25;           /* AF_AX25 device */
689         dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
690         dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
691         dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
692         memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
693         memcpy(dev->dev_addr, &ax25_defaddr, AX25_ADDR_LEN);
694         dev->tx_queue_len = 16;
695 }
696
697 /* --------------------------------------------------------------------- */
698 struct net_device *hdlcdrv_register(const struct hdlcdrv_ops *ops,
699                                     unsigned int privsize, const char *ifname,
700                                     unsigned int baseaddr, unsigned int irq, 
701                                     unsigned int dma) 
702 {
703         struct net_device *dev;
704         struct hdlcdrv_state *s;
705         int err;
706
707         BUG_ON(ops == NULL);
708
709         if (privsize < sizeof(struct hdlcdrv_state))
710                 privsize = sizeof(struct hdlcdrv_state);
711
712         dev = alloc_netdev(privsize, ifname, hdlcdrv_setup);
713         if (!dev)
714                 return ERR_PTR(-ENOMEM);
715
716         /*
717          * initialize part of the hdlcdrv_state struct
718          */
719         s = netdev_priv(dev);
720         s->magic = HDLCDRV_MAGIC;
721         s->ops = ops;
722         dev->base_addr = baseaddr;
723         dev->irq = irq;
724         dev->dma = dma;
725
726         err = register_netdev(dev);
727         if (err < 0) {
728                 printk(KERN_WARNING "hdlcdrv: cannot register net "
729                        "device %s\n", dev->name);
730                 free_netdev(dev);
731                 dev = ERR_PTR(err);
732         }
733         return dev;
734 }
735
736 /* --------------------------------------------------------------------- */
737
738 void hdlcdrv_unregister(struct net_device *dev) 
739 {
740         struct hdlcdrv_state *s = netdev_priv(dev);
741
742         BUG_ON(s->magic != HDLCDRV_MAGIC);
743
744         if (s->opened && s->ops->close)
745                 s->ops->close(dev);
746         unregister_netdev(dev);
747         
748         free_netdev(dev);
749 }
750
751 /* --------------------------------------------------------------------- */
752
753 EXPORT_SYMBOL(hdlcdrv_receiver);
754 EXPORT_SYMBOL(hdlcdrv_transmitter);
755 EXPORT_SYMBOL(hdlcdrv_arbitrate);
756 EXPORT_SYMBOL(hdlcdrv_register);
757 EXPORT_SYMBOL(hdlcdrv_unregister);
758
759 /* --------------------------------------------------------------------- */
760
761 static int __init hdlcdrv_init_driver(void)
762 {
763         printk(KERN_INFO "hdlcdrv: (C) 1996-2000 Thomas Sailer HB9JNX/AE4WA\n");
764         printk(KERN_INFO "hdlcdrv: version 0.8 compiled " __TIME__ " " __DATE__ "\n");
765         return 0;
766 }
767
768 /* --------------------------------------------------------------------- */
769
770 static void __exit hdlcdrv_cleanup_driver(void)
771 {
772         printk(KERN_INFO "hdlcdrv: cleanup\n");
773 }
774
775 /* --------------------------------------------------------------------- */
776
777 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
778 MODULE_DESCRIPTION("Packet Radio network interface HDLC encoder/decoder");
779 MODULE_LICENSE("GPL");
780 module_init(hdlcdrv_init_driver);
781 module_exit(hdlcdrv_cleanup_driver);
782
783 /* --------------------------------------------------------------------- */