Merge branches 'topic/fix/misc' and 'topic/fix/asoc' into for-linus
[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         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 /* --------------------------------------------------------------------- */