1// SPDX-License-Identifier: GPL-2.0-or-later
2/*****************************************************************************/
3
4/*
5 * hdlcdrv.c -- HDLC packet radio network driver.
6 *
7 * Copyright (C) 1996-2000 Thomas Sailer (sailer@ife.ee.ethz.ch)
8 *
9 * Please note that the GPL allows you to use the driver, NOT the radio.
10 * In order to use the radio, you need a license from the communications
11 * authority of your country.
12 *
13 * The driver was derived from Donald Beckers skeleton.c
14 * Written 1993-94 by Donald Becker.
15 *
16 * History:
17 * 0.1 21.09.1996 Started
18 * 18.10.1996 Changed to new user space access routines
19 * (copy_{to,from}_user)
20 * 0.2 21.11.1996 various small changes
21 * 0.3 03.03.1997 fixed (hopefully) IP not working with ax.25 as a module
22 * 0.4 16.04.1997 init code/data tagged
23 * 0.5 30.07.1997 made HDLC buffers bigger (solves a problem with the
24 * soundmodem driver)
25 * 0.6 05.04.1998 add spinlocks
26 * 0.7 03.08.1999 removed some old compatibility cruft
27 * 0.8 12.02.2000 adapted to softnet driver interface
28 */
29
30/*****************************************************************************/
31
32#include <linux/capability.h>
33#include <linux/compat.h>
34#include <linux/module.h>
35#include <linux/types.h>
36#include <linux/net.h>
37#include <linux/in.h>
38#include <linux/if.h>
39#include <linux/errno.h>
40#include <linux/init.h>
41#include <linux/bitops.h>
42
43#include <linux/netdevice.h>
44#include <linux/if_arp.h>
45#include <linux/skbuff.h>
46#include <linux/hdlcdrv.h>
47#include <linux/random.h>
48#include <net/ax25.h>
49#include <linux/uaccess.h>
50
51#include <linux/crc-ccitt.h>
52
53/* --------------------------------------------------------------------- */
54
55#define KISS_VERBOSE
56
57/* --------------------------------------------------------------------- */
58
59#define PARAM_TXDELAY 1
60#define PARAM_PERSIST 2
61#define PARAM_SLOTTIME 3
62#define PARAM_TXTAIL 4
63#define PARAM_FULLDUP 5
64#define PARAM_HARDWARE 6
65#define PARAM_RETURN 255
66
67/* --------------------------------------------------------------------- */
68/*
69 * the CRC routines are stolen from WAMPES
70 * by Dieter Deyke
71 */
72
73
74/*---------------------------------------------------------------------------*/
75
76static inline void append_crc_ccitt(unsigned char *buffer, int len)
77{
78 unsigned int crc = crc_ccitt(crc: 0xffff, buffer, len) ^ 0xffff;
79 buffer += len;
80 *buffer++ = crc;
81 *buffer++ = crc >> 8;
82}
83
84/*---------------------------------------------------------------------------*/
85
86static inline int check_crc_ccitt(const unsigned char *buf, int cnt)
87{
88 return (crc_ccitt(crc: 0xffff, buffer: buf, len: cnt) & 0xffff) == 0xf0b8;
89}
90
91/*---------------------------------------------------------------------------*/
92
93#if 0
94static int calc_crc_ccitt(const unsigned char *buf, int cnt)
95{
96 unsigned int crc = 0xffff;
97
98 for (; cnt > 0; cnt--)
99 crc = (crc >> 8) ^ crc_ccitt_table[(crc ^ *buf++) & 0xff];
100 crc ^= 0xffff;
101 return crc & 0xffff;
102}
103#endif
104
105/* ---------------------------------------------------------------------- */
106
107#define tenms_to_2flags(s,tenms) ((tenms * s->par.bitrate) / 100 / 16)
108
109/* ---------------------------------------------------------------------- */
110/*
111 * The HDLC routines
112 */
113
114static int hdlc_rx_add_bytes(struct hdlcdrv_state *s, unsigned int bits,
115 int num)
116{
117 int added = 0;
118
119 while (s->hdlcrx.rx_state && num >= 8) {
120 if (s->hdlcrx.len >= sizeof(s->hdlcrx.buffer)) {
121 s->hdlcrx.rx_state = 0;
122 return 0;
123 }
124 *s->hdlcrx.bp++ = bits >> (32-num);
125 s->hdlcrx.len++;
126 num -= 8;
127 added += 8;
128 }
129 return added;
130}
131
132static void hdlc_rx_flag(struct net_device *dev, struct hdlcdrv_state *s)
133{
134 struct sk_buff *skb;
135 int pkt_len;
136 unsigned char *cp;
137
138 if (s->hdlcrx.len < 4)
139 return;
140 if (!check_crc_ccitt(buf: s->hdlcrx.buffer, cnt: s->hdlcrx.len))
141 return;
142 pkt_len = s->hdlcrx.len - 2 + 1; /* KISS kludge */
143 if (!(skb = dev_alloc_skb(length: pkt_len))) {
144 printk("%s: memory squeeze, dropping packet\n", dev->name);
145 dev->stats.rx_dropped++;
146 return;
147 }
148 cp = skb_put(skb, len: pkt_len);
149 *cp++ = 0; /* KISS kludge */
150 memcpy(cp, s->hdlcrx.buffer, pkt_len - 1);
151 skb->protocol = ax25_type_trans(skb, dev);
152 netif_rx(skb);
153 dev->stats.rx_packets++;
154}
155
156void hdlcdrv_receiver(struct net_device *dev, struct hdlcdrv_state *s)
157{
158 int i;
159 unsigned int mask1, mask2, mask3, mask4, mask5, mask6, word;
160
161 if (!s || s->magic != HDLCDRV_MAGIC)
162 return;
163 if (test_and_set_bit(nr: 0, addr: &s->hdlcrx.in_hdlc_rx))
164 return;
165
166 while (!hdlcdrv_hbuf_empty(hb: &s->hdlcrx.hbuf)) {
167 word = hdlcdrv_hbuf_get(hb: &s->hdlcrx.hbuf);
168
169#ifdef HDLCDRV_DEBUG
170 hdlcdrv_add_bitbuffer_word(buf: &s->bitbuf_hdlc, bits: word);
171#endif /* HDLCDRV_DEBUG */
172 s->hdlcrx.bitstream >>= 16;
173 s->hdlcrx.bitstream |= word << 16;
174 s->hdlcrx.bitbuf >>= 16;
175 s->hdlcrx.bitbuf |= word << 16;
176 s->hdlcrx.numbits += 16;
177 for(i = 15, mask1 = 0x1fc00, mask2 = 0x1fe00, mask3 = 0x0fc00,
178 mask4 = 0x1f800, mask5 = 0xf800, mask6 = 0xffff;
179 i >= 0;
180 i--, mask1 <<= 1, mask2 <<= 1, mask3 <<= 1, mask4 <<= 1,
181 mask5 <<= 1, mask6 = (mask6 << 1) | 1) {
182 if ((s->hdlcrx.bitstream & mask1) == mask1)
183 s->hdlcrx.rx_state = 0; /* abort received */
184 else if ((s->hdlcrx.bitstream & mask2) == mask3) {
185 /* flag received */
186 if (s->hdlcrx.rx_state) {
187 hdlc_rx_add_bytes(s, bits: s->hdlcrx.bitbuf
188 << (8+i),
189 num: s->hdlcrx.numbits
190 -8-i);
191 hdlc_rx_flag(dev, s);
192 }
193 s->hdlcrx.len = 0;
194 s->hdlcrx.bp = s->hdlcrx.buffer;
195 s->hdlcrx.rx_state = 1;
196 s->hdlcrx.numbits = i;
197 } else if ((s->hdlcrx.bitstream & mask4) == mask5) {
198 /* stuffed bit */
199 s->hdlcrx.numbits--;
200 s->hdlcrx.bitbuf = (s->hdlcrx.bitbuf & (~mask6)) |
201 ((s->hdlcrx.bitbuf & mask6) << 1);
202 }
203 }
204 s->hdlcrx.numbits -= hdlc_rx_add_bytes(s, bits: s->hdlcrx.bitbuf,
205 num: s->hdlcrx.numbits);
206 }
207 clear_bit(nr: 0, addr: &s->hdlcrx.in_hdlc_rx);
208}
209
210/* ---------------------------------------------------------------------- */
211
212static inline void do_kiss_params(struct hdlcdrv_state *s,
213 unsigned char *data, unsigned long len)
214{
215
216#ifdef KISS_VERBOSE
217#define PKP(a,b) printk(KERN_INFO "hdlcdrv.c: channel params: " a "\n", b)
218#else /* KISS_VERBOSE */
219#define PKP(a,b)
220#endif /* KISS_VERBOSE */
221
222 if (len < 2)
223 return;
224 switch(data[0]) {
225 case PARAM_TXDELAY:
226 s->ch_params.tx_delay = data[1];
227 PKP("TX delay = %ums", 10 * s->ch_params.tx_delay);
228 break;
229 case PARAM_PERSIST:
230 s->ch_params.ppersist = data[1];
231 PKP("p persistence = %u", s->ch_params.ppersist);
232 break;
233 case PARAM_SLOTTIME:
234 s->ch_params.slottime = data[1];
235 PKP("slot time = %ums", s->ch_params.slottime);
236 break;
237 case PARAM_TXTAIL:
238 s->ch_params.tx_tail = data[1];
239 PKP("TX tail = %ums", s->ch_params.tx_tail);
240 break;
241 case PARAM_FULLDUP:
242 s->ch_params.fulldup = !!data[1];
243 PKP("%s duplex", s->ch_params.fulldup ? "full" : "half");
244 break;
245 default:
246 break;
247 }
248#undef PKP
249}
250
251/* ---------------------------------------------------------------------- */
252
253void hdlcdrv_transmitter(struct net_device *dev, struct hdlcdrv_state *s)
254{
255 unsigned int mask1, mask2, mask3;
256 int i;
257 struct sk_buff *skb;
258 int pkt_len;
259
260 if (!s || s->magic != HDLCDRV_MAGIC)
261 return;
262 if (test_and_set_bit(nr: 0, addr: &s->hdlctx.in_hdlc_tx))
263 return;
264 for (;;) {
265 if (s->hdlctx.numbits >= 16) {
266 if (hdlcdrv_hbuf_full(hb: &s->hdlctx.hbuf)) {
267 clear_bit(nr: 0, addr: &s->hdlctx.in_hdlc_tx);
268 return;
269 }
270 hdlcdrv_hbuf_put(hb: &s->hdlctx.hbuf, val: s->hdlctx.bitbuf);
271 s->hdlctx.bitbuf >>= 16;
272 s->hdlctx.numbits -= 16;
273 }
274 switch (s->hdlctx.tx_state) {
275 default:
276 clear_bit(nr: 0, addr: &s->hdlctx.in_hdlc_tx);
277 return;
278 case 0:
279 case 1:
280 if (s->hdlctx.numflags) {
281 s->hdlctx.numflags--;
282 s->hdlctx.bitbuf |=
283 0x7e7e << s->hdlctx.numbits;
284 s->hdlctx.numbits += 16;
285 break;
286 }
287 if (s->hdlctx.tx_state == 1) {
288 clear_bit(nr: 0, addr: &s->hdlctx.in_hdlc_tx);
289 return;
290 }
291 if (!(skb = s->skb)) {
292 int flgs = tenms_to_2flags(s, s->ch_params.tx_tail);
293 if (flgs < 2)
294 flgs = 2;
295 s->hdlctx.tx_state = 1;
296 s->hdlctx.numflags = flgs;
297 break;
298 }
299 s->skb = NULL;
300 netif_wake_queue(dev);
301 pkt_len = skb->len-1; /* strip KISS byte */
302 if (pkt_len >= HDLCDRV_MAXFLEN || pkt_len < 2) {
303 s->hdlctx.tx_state = 0;
304 s->hdlctx.numflags = 1;
305 dev_kfree_skb_irq(skb);
306 break;
307 }
308 skb_copy_from_linear_data_offset(skb, offset: 1,
309 to: s->hdlctx.buffer,
310 len: pkt_len);
311 dev_kfree_skb_irq(skb);
312 s->hdlctx.bp = s->hdlctx.buffer;
313 append_crc_ccitt(buffer: s->hdlctx.buffer, len: pkt_len);
314 s->hdlctx.len = pkt_len+2; /* the appended CRC */
315 s->hdlctx.tx_state = 2;
316 s->hdlctx.bitstream = 0;
317 dev->stats.tx_packets++;
318 break;
319 case 2:
320 if (!s->hdlctx.len) {
321 s->hdlctx.tx_state = 0;
322 s->hdlctx.numflags = 1;
323 break;
324 }
325 s->hdlctx.len--;
326 s->hdlctx.bitbuf |= *s->hdlctx.bp <<
327 s->hdlctx.numbits;
328 s->hdlctx.bitstream >>= 8;
329 s->hdlctx.bitstream |= (*s->hdlctx.bp++) << 16;
330 mask1 = 0x1f000;
331 mask2 = 0x10000;
332 mask3 = 0xffffffff >> (31-s->hdlctx.numbits);
333 s->hdlctx.numbits += 8;
334 for(i = 0; i < 8; i++, mask1 <<= 1, mask2 <<= 1,
335 mask3 = (mask3 << 1) | 1) {
336 if ((s->hdlctx.bitstream & mask1) != mask1)
337 continue;
338 s->hdlctx.bitstream &= ~mask2;
339 s->hdlctx.bitbuf =
340 (s->hdlctx.bitbuf & mask3) |
341 ((s->hdlctx.bitbuf &
342 (~mask3)) << 1);
343 s->hdlctx.numbits++;
344 mask3 = (mask3 << 1) | 1;
345 }
346 break;
347 }
348 }
349}
350
351/* ---------------------------------------------------------------------- */
352
353static void start_tx(struct net_device *dev, struct hdlcdrv_state *s)
354{
355 s->hdlctx.tx_state = 0;
356 s->hdlctx.numflags = tenms_to_2flags(s, s->ch_params.tx_delay);
357 s->hdlctx.bitbuf = s->hdlctx.bitstream = s->hdlctx.numbits = 0;
358 hdlcdrv_transmitter(dev, s);
359 s->hdlctx.ptt = 1;
360 s->ptt_keyed++;
361}
362
363/* ---------------------------------------------------------------------- */
364
365void hdlcdrv_arbitrate(struct net_device *dev, struct hdlcdrv_state *s)
366{
367 if (!s || s->magic != HDLCDRV_MAGIC || s->hdlctx.ptt || !s->skb)
368 return;
369 if (s->ch_params.fulldup) {
370 start_tx(dev, s);
371 return;
372 }
373 if (s->hdlcrx.dcd) {
374 s->hdlctx.slotcnt = s->ch_params.slottime;
375 return;
376 }
377 if ((--s->hdlctx.slotcnt) > 0)
378 return;
379 s->hdlctx.slotcnt = s->ch_params.slottime;
380 if (get_random_u8() > s->ch_params.ppersist)
381 return;
382 start_tx(dev, s);
383}
384
385/* --------------------------------------------------------------------- */
386/*
387 * ===================== network driver interface =========================
388 */
389
390static netdev_tx_t hdlcdrv_send_packet(struct sk_buff *skb,
391 struct net_device *dev)
392{
393 struct hdlcdrv_state *sm = netdev_priv(dev);
394
395 if (skb->protocol == htons(ETH_P_IP))
396 return ax25_ip_xmit(skb);
397
398 if (skb->data[0] != 0) {
399 do_kiss_params(s: sm, data: skb->data, len: skb->len);
400 dev_kfree_skb(skb);
401 return NETDEV_TX_OK;
402 }
403 if (sm->skb) {
404 dev_kfree_skb(skb);
405 return NETDEV_TX_OK;
406 }
407 netif_stop_queue(dev);
408 sm->skb = skb;
409 return NETDEV_TX_OK;
410}
411
412/* --------------------------------------------------------------------- */
413
414static int hdlcdrv_set_mac_address(struct net_device *dev, void *addr)
415{
416 struct sockaddr *sa = (struct sockaddr *)addr;
417
418 /* addr is an AX.25 shifted ASCII mac address */
419 dev_addr_set(dev, addr: sa->sa_data);
420 return 0;
421}
422
423/* --------------------------------------------------------------------- */
424/*
425 * Open/initialize the board. This is called (in the current kernel)
426 * sometime after booting when the 'ifconfig' program is run.
427 *
428 * This routine should set everything up anew at each open, even
429 * registers that "should" only need to be set once at boot, so that
430 * there is non-reboot way to recover if something goes wrong.
431 */
432
433static int hdlcdrv_open(struct net_device *dev)
434{
435 struct hdlcdrv_state *s = netdev_priv(dev);
436 int i;
437
438 if (!s->ops || !s->ops->open)
439 return -ENODEV;
440
441 /*
442 * initialise some variables
443 */
444 s->opened = 1;
445 s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
446 s->hdlcrx.in_hdlc_rx = 0;
447 s->hdlcrx.rx_state = 0;
448
449 s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
450 s->hdlctx.in_hdlc_tx = 0;
451 s->hdlctx.tx_state = 1;
452 s->hdlctx.numflags = 0;
453 s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
454 s->hdlctx.ptt = 0;
455 s->hdlctx.slotcnt = s->ch_params.slottime;
456 s->hdlctx.calibrate = 0;
457
458 i = s->ops->open(dev);
459 if (i)
460 return i;
461 netif_start_queue(dev);
462 return 0;
463}
464
465/* --------------------------------------------------------------------- */
466/*
467 * The inverse routine to hdlcdrv_open().
468 */
469
470static int hdlcdrv_close(struct net_device *dev)
471{
472 struct hdlcdrv_state *s = netdev_priv(dev);
473 int i = 0;
474
475 netif_stop_queue(dev);
476
477 if (s->ops && s->ops->close)
478 i = s->ops->close(dev);
479 dev_kfree_skb(s->skb);
480 s->skb = NULL;
481 s->opened = 0;
482 return i;
483}
484
485/* --------------------------------------------------------------------- */
486
487static int hdlcdrv_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
488 void __user *data, int cmd)
489{
490 struct hdlcdrv_state *s = netdev_priv(dev);
491 struct hdlcdrv_ioctl bi;
492
493 if (cmd != SIOCDEVPRIVATE)
494 return -ENOIOCTLCMD;
495
496 if (in_compat_syscall()) /* to be implemented */
497 return -ENOIOCTLCMD;
498
499 if (copy_from_user(to: &bi, from: data, n: sizeof(bi)))
500 return -EFAULT;
501
502 switch (bi.cmd) {
503 default:
504 if (s->ops && s->ops->ioctl)
505 return s->ops->ioctl(dev, data, &bi, cmd);
506 return -ENOIOCTLCMD;
507
508 case HDLCDRVCTL_GETCHANNELPAR:
509 bi.data.cp.tx_delay = s->ch_params.tx_delay;
510 bi.data.cp.tx_tail = s->ch_params.tx_tail;
511 bi.data.cp.slottime = s->ch_params.slottime;
512 bi.data.cp.ppersist = s->ch_params.ppersist;
513 bi.data.cp.fulldup = s->ch_params.fulldup;
514 break;
515
516 case HDLCDRVCTL_SETCHANNELPAR:
517 if (!capable(CAP_NET_ADMIN))
518 return -EACCES;
519 s->ch_params.tx_delay = bi.data.cp.tx_delay;
520 s->ch_params.tx_tail = bi.data.cp.tx_tail;
521 s->ch_params.slottime = bi.data.cp.slottime;
522 s->ch_params.ppersist = bi.data.cp.ppersist;
523 s->ch_params.fulldup = bi.data.cp.fulldup;
524 s->hdlctx.slotcnt = 1;
525 return 0;
526
527 case HDLCDRVCTL_GETMODEMPAR:
528 bi.data.mp.iobase = dev->base_addr;
529 bi.data.mp.irq = dev->irq;
530 bi.data.mp.dma = dev->dma;
531 bi.data.mp.dma2 = s->ptt_out.dma2;
532 bi.data.mp.seriobase = s->ptt_out.seriobase;
533 bi.data.mp.pariobase = s->ptt_out.pariobase;
534 bi.data.mp.midiiobase = s->ptt_out.midiiobase;
535 break;
536
537 case HDLCDRVCTL_SETMODEMPAR:
538 if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
539 return -EACCES;
540 dev->base_addr = bi.data.mp.iobase;
541 dev->irq = bi.data.mp.irq;
542 dev->dma = bi.data.mp.dma;
543 s->ptt_out.dma2 = bi.data.mp.dma2;
544 s->ptt_out.seriobase = bi.data.mp.seriobase;
545 s->ptt_out.pariobase = bi.data.mp.pariobase;
546 s->ptt_out.midiiobase = bi.data.mp.midiiobase;
547 return 0;
548
549 case HDLCDRVCTL_GETSTAT:
550 bi.data.cs.ptt = hdlcdrv_ptt(s);
551 bi.data.cs.dcd = s->hdlcrx.dcd;
552 bi.data.cs.ptt_keyed = s->ptt_keyed;
553 bi.data.cs.tx_packets = dev->stats.tx_packets;
554 bi.data.cs.tx_errors = dev->stats.tx_errors;
555 bi.data.cs.rx_packets = dev->stats.rx_packets;
556 bi.data.cs.rx_errors = dev->stats.rx_errors;
557 break;
558
559 case HDLCDRVCTL_OLDGETSTAT:
560 bi.data.ocs.ptt = hdlcdrv_ptt(s);
561 bi.data.ocs.dcd = s->hdlcrx.dcd;
562 bi.data.ocs.ptt_keyed = s->ptt_keyed;
563 break;
564
565 case HDLCDRVCTL_CALIBRATE:
566 if(!capable(CAP_SYS_RAWIO))
567 return -EPERM;
568 if (s->par.bitrate <= 0)
569 return -EINVAL;
570 if (bi.data.calibrate > INT_MAX / s->par.bitrate)
571 return -EINVAL;
572 s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
573 return 0;
574
575 case HDLCDRVCTL_GETSAMPLES:
576#ifndef HDLCDRV_DEBUG
577 return -EPERM;
578#else /* HDLCDRV_DEBUG */
579 if (s->bitbuf_channel.rd == s->bitbuf_channel.wr)
580 return -EAGAIN;
581 bi.data.bits =
582 s->bitbuf_channel.buffer[s->bitbuf_channel.rd];
583 s->bitbuf_channel.rd = (s->bitbuf_channel.rd+1) %
584 sizeof(s->bitbuf_channel.buffer);
585 break;
586#endif /* HDLCDRV_DEBUG */
587
588 case HDLCDRVCTL_GETBITS:
589#ifndef HDLCDRV_DEBUG
590 return -EPERM;
591#else /* HDLCDRV_DEBUG */
592 if (s->bitbuf_hdlc.rd == s->bitbuf_hdlc.wr)
593 return -EAGAIN;
594 bi.data.bits =
595 s->bitbuf_hdlc.buffer[s->bitbuf_hdlc.rd];
596 s->bitbuf_hdlc.rd = (s->bitbuf_hdlc.rd+1) %
597 sizeof(s->bitbuf_hdlc.buffer);
598 break;
599#endif /* HDLCDRV_DEBUG */
600
601 case HDLCDRVCTL_DRIVERNAME:
602 if (s->ops && s->ops->drvname) {
603 strscpy(p: bi.data.drivername, q: s->ops->drvname,
604 size: sizeof(bi.data.drivername));
605 break;
606 }
607 bi.data.drivername[0] = '\0';
608 break;
609
610 }
611 if (copy_to_user(to: data, from: &bi, n: sizeof(bi)))
612 return -EFAULT;
613 return 0;
614
615}
616
617/* --------------------------------------------------------------------- */
618
619static const struct net_device_ops hdlcdrv_netdev = {
620 .ndo_open = hdlcdrv_open,
621 .ndo_stop = hdlcdrv_close,
622 .ndo_start_xmit = hdlcdrv_send_packet,
623 .ndo_siocdevprivate = hdlcdrv_siocdevprivate,
624 .ndo_set_mac_address = hdlcdrv_set_mac_address,
625};
626
627/*
628 * Initialize fields in hdlcdrv
629 */
630static void hdlcdrv_setup(struct net_device *dev)
631{
632 static const struct hdlcdrv_channel_params dflt_ch_params = {
633 20, 2, 10, 40, 0
634 };
635 struct hdlcdrv_state *s = netdev_priv(dev);
636
637 /*
638 * initialize the hdlcdrv_state struct
639 */
640 s->ch_params = dflt_ch_params;
641 s->ptt_keyed = 0;
642
643 spin_lock_init(&s->hdlcrx.hbuf.lock);
644 s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
645 s->hdlcrx.in_hdlc_rx = 0;
646 s->hdlcrx.rx_state = 0;
647
648 spin_lock_init(&s->hdlctx.hbuf.lock);
649 s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
650 s->hdlctx.in_hdlc_tx = 0;
651 s->hdlctx.tx_state = 1;
652 s->hdlctx.numflags = 0;
653 s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
654 s->hdlctx.ptt = 0;
655 s->hdlctx.slotcnt = s->ch_params.slottime;
656 s->hdlctx.calibrate = 0;
657
658#ifdef HDLCDRV_DEBUG
659 s->bitbuf_channel.rd = s->bitbuf_channel.wr = 0;
660 s->bitbuf_channel.shreg = 0x80;
661
662 s->bitbuf_hdlc.rd = s->bitbuf_hdlc.wr = 0;
663 s->bitbuf_hdlc.shreg = 0x80;
664#endif /* HDLCDRV_DEBUG */
665
666
667 /* Fill in the fields of the device structure */
668
669 s->skb = NULL;
670
671 dev->netdev_ops = &hdlcdrv_netdev;
672 dev->header_ops = &ax25_header_ops;
673
674 dev->type = ARPHRD_AX25; /* AF_AX25 device */
675 dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
676 dev->mtu = AX25_DEF_PACLEN; /* eth_mtu is the default */
677 dev->addr_len = AX25_ADDR_LEN; /* sizeof an ax.25 address */
678 memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
679 dev_addr_set(dev, addr: (u8 *)&ax25_defaddr);
680 dev->tx_queue_len = 16;
681}
682
683/* --------------------------------------------------------------------- */
684struct net_device *hdlcdrv_register(const struct hdlcdrv_ops *ops,
685 unsigned int privsize, const char *ifname,
686 unsigned int baseaddr, unsigned int irq,
687 unsigned int dma)
688{
689 struct net_device *dev;
690 struct hdlcdrv_state *s;
691 int err;
692
693 if (privsize < sizeof(struct hdlcdrv_state))
694 privsize = sizeof(struct hdlcdrv_state);
695
696 dev = alloc_netdev(privsize, ifname, NET_NAME_UNKNOWN, hdlcdrv_setup);
697 if (!dev)
698 return ERR_PTR(error: -ENOMEM);
699
700 /*
701 * initialize part of the hdlcdrv_state struct
702 */
703 s = netdev_priv(dev);
704 s->magic = HDLCDRV_MAGIC;
705 s->ops = ops;
706 dev->base_addr = baseaddr;
707 dev->irq = irq;
708 dev->dma = dma;
709
710 err = register_netdev(dev);
711 if (err < 0) {
712 printk(KERN_WARNING "hdlcdrv: cannot register net "
713 "device %s\n", dev->name);
714 free_netdev(dev);
715 dev = ERR_PTR(error: err);
716 }
717 return dev;
718}
719
720/* --------------------------------------------------------------------- */
721
722void hdlcdrv_unregister(struct net_device *dev)
723{
724 struct hdlcdrv_state *s = netdev_priv(dev);
725
726 BUG_ON(s->magic != HDLCDRV_MAGIC);
727
728 if (s->opened && s->ops->close)
729 s->ops->close(dev);
730 unregister_netdev(dev);
731
732 free_netdev(dev);
733}
734
735/* --------------------------------------------------------------------- */
736
737EXPORT_SYMBOL(hdlcdrv_receiver);
738EXPORT_SYMBOL(hdlcdrv_transmitter);
739EXPORT_SYMBOL(hdlcdrv_arbitrate);
740EXPORT_SYMBOL(hdlcdrv_register);
741EXPORT_SYMBOL(hdlcdrv_unregister);
742
743/* --------------------------------------------------------------------- */
744
745static int __init hdlcdrv_init_driver(void)
746{
747 printk(KERN_INFO "hdlcdrv: (C) 1996-2000 Thomas Sailer HB9JNX/AE4WA\n");
748 printk(KERN_INFO "hdlcdrv: version 0.8\n");
749 return 0;
750}
751
752/* --------------------------------------------------------------------- */
753
754static void __exit hdlcdrv_cleanup_driver(void)
755{
756 printk(KERN_INFO "hdlcdrv: cleanup\n");
757}
758
759/* --------------------------------------------------------------------- */
760
761MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
762MODULE_DESCRIPTION("Packet Radio network interface HDLC encoder/decoder");
763MODULE_LICENSE("GPL");
764module_init(hdlcdrv_init_driver);
765module_exit(hdlcdrv_cleanup_driver);
766
767/* --------------------------------------------------------------------- */
768

source code of linux/drivers/net/hamradio/hdlcdrv.c