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v6.8
  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(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(0xffff, buf, 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(s->hdlcrx.buffer, s->hdlcrx.len)) 
141		return;
142	pkt_len = s->hdlcrx.len - 2 + 1; /* KISS kludge */
143	if (!(skb = dev_alloc_skb(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, 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(0, &s->hdlcrx.in_hdlc_rx))
164		return;
165
166	while (!hdlcdrv_hbuf_empty(&s->hdlcrx.hbuf)) {
167		word = hdlcdrv_hbuf_get(&s->hdlcrx.hbuf);	
168
169#ifdef HDLCDRV_DEBUG
170		hdlcdrv_add_bitbuffer_word(&s->bitbuf_hdlc, 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, s->hdlcrx.bitbuf 
188							  << (8+i),
189							  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, s->hdlcrx.bitbuf,
205						       s->hdlcrx.numbits);
206	}
207	clear_bit(0, &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(0, &s->hdlctx.in_hdlc_tx))
263		return;
264	for (;;) {
265		if (s->hdlctx.numbits >= 16) {
266			if (hdlcdrv_hbuf_full(&s->hdlctx.hbuf)) {
267				clear_bit(0, &s->hdlctx.in_hdlc_tx);
268				return;
269			}
270			hdlcdrv_hbuf_put(&s->hdlctx.hbuf, 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(0, &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(0, &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, 1,
309							 s->hdlctx.buffer,
310							 pkt_len);
311			dev_kfree_skb_irq(skb);
312			s->hdlctx.bp = s->hdlctx.buffer;
313			append_crc_ccitt(s->hdlctx.buffer, 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(sm, skb->data, 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, 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(&bi, data, 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(bi.data.drivername, s->ops->drvname,
604				sizeof(bi.data.drivername));
605			break;
606		}
607		bi.data.drivername[0] = '\0';
608		break;
609		
610	}
611	if (copy_to_user(data, &bi, 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, (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(-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(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/* --------------------------------------------------------------------- */
v3.1
 
  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/capability.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/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
 88static 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
 98static 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
106static 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
126static 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
144static 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		dev->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->stats.rx_packets++;
166}
167
168void 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
224static 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
265void 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			dev->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
365static 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
377void 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
402static netdev_tx_t hdlcdrv_send_packet(struct sk_buff *skb,
403				       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 NETDEV_TX_OK;
411	}
412	if (sm->skb)
413		return NETDEV_TX_LOCKED;
 
 
414	netif_stop_queue(dev);
415	sm->skb = skb;
416	return NETDEV_TX_OK;
417}
418
419/* --------------------------------------------------------------------- */
420
421static 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 * Open/initialize the board. This is called (in the current kernel)
433 * sometime after booting when the 'ifconfig' program is run.
434 *
435 * This routine should set everything up anew at each open, even
436 * registers that "should" only need to be set once at boot, so that
437 * there is non-reboot way to recover if something goes wrong.
438 */
439
440static int hdlcdrv_open(struct net_device *dev)
441{
442	struct hdlcdrv_state *s = netdev_priv(dev);
443	int i;
444
445	if (!s->ops || !s->ops->open)
446		return -ENODEV;
447
448	/*
449	 * initialise some variables
450	 */
451	s->opened = 1;
452	s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
453	s->hdlcrx.in_hdlc_rx = 0;
454	s->hdlcrx.rx_state = 0;
455	
456	s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
457	s->hdlctx.in_hdlc_tx = 0;
458	s->hdlctx.tx_state = 1;
459	s->hdlctx.numflags = 0;
460	s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
461	s->hdlctx.ptt = 0;
462	s->hdlctx.slotcnt = s->ch_params.slottime;
463	s->hdlctx.calibrate = 0;
464
465	i = s->ops->open(dev);
466	if (i)
467		return i;
468	netif_start_queue(dev);
469	return 0;
470}
471
472/* --------------------------------------------------------------------- */
473/* 
474 * The inverse routine to hdlcdrv_open(). 
475 */
476
477static int hdlcdrv_close(struct net_device *dev)
478{
479	struct hdlcdrv_state *s = netdev_priv(dev);
480	int i = 0;
481
482	netif_stop_queue(dev);
483
484	if (s->ops && s->ops->close)
485		i = s->ops->close(dev);
486	if (s->skb)
487		dev_kfree_skb(s->skb);
488	s->skb = NULL;
489	s->opened = 0;
490	return i;
491}
492
493/* --------------------------------------------------------------------- */
494
495static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 
496{
497	struct hdlcdrv_state *s = netdev_priv(dev);
498	struct hdlcdrv_ioctl bi;
499
500	if (cmd != SIOCDEVPRIVATE) {
501		if (s->ops && s->ops->ioctl)
502			return s->ops->ioctl(dev, ifr, &bi, cmd);
 
503		return -ENOIOCTLCMD;
504	}
505	if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
506		return -EFAULT;
507
508	switch (bi.cmd) {
509	default:
510		if (s->ops && s->ops->ioctl)
511			return s->ops->ioctl(dev, ifr, &bi, cmd);
512		return -ENOIOCTLCMD;
513
514	case HDLCDRVCTL_GETCHANNELPAR:
515		bi.data.cp.tx_delay = s->ch_params.tx_delay;
516		bi.data.cp.tx_tail = s->ch_params.tx_tail;
517		bi.data.cp.slottime = s->ch_params.slottime;
518		bi.data.cp.ppersist = s->ch_params.ppersist;
519		bi.data.cp.fulldup = s->ch_params.fulldup;
520		break;
521
522	case HDLCDRVCTL_SETCHANNELPAR:
523		if (!capable(CAP_NET_ADMIN))
524			return -EACCES;
525		s->ch_params.tx_delay = bi.data.cp.tx_delay;
526		s->ch_params.tx_tail = bi.data.cp.tx_tail;
527		s->ch_params.slottime = bi.data.cp.slottime;
528		s->ch_params.ppersist = bi.data.cp.ppersist;
529		s->ch_params.fulldup = bi.data.cp.fulldup;
530		s->hdlctx.slotcnt = 1;
531		return 0;
532		
533	case HDLCDRVCTL_GETMODEMPAR:
534		bi.data.mp.iobase = dev->base_addr;
535		bi.data.mp.irq = dev->irq;
536		bi.data.mp.dma = dev->dma;
537		bi.data.mp.dma2 = s->ptt_out.dma2;
538		bi.data.mp.seriobase = s->ptt_out.seriobase;
539		bi.data.mp.pariobase = s->ptt_out.pariobase;
540		bi.data.mp.midiiobase = s->ptt_out.midiiobase;
541		break;
542
543	case HDLCDRVCTL_SETMODEMPAR:
544		if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
545			return -EACCES;
546		dev->base_addr = bi.data.mp.iobase;
547		dev->irq = bi.data.mp.irq;
548		dev->dma = bi.data.mp.dma;
549		s->ptt_out.dma2 = bi.data.mp.dma2;
550		s->ptt_out.seriobase = bi.data.mp.seriobase;
551		s->ptt_out.pariobase = bi.data.mp.pariobase;
552		s->ptt_out.midiiobase = bi.data.mp.midiiobase;
553		return 0;	
554	
555	case HDLCDRVCTL_GETSTAT:
556		bi.data.cs.ptt = hdlcdrv_ptt(s);
557		bi.data.cs.dcd = s->hdlcrx.dcd;
558		bi.data.cs.ptt_keyed = s->ptt_keyed;
559		bi.data.cs.tx_packets = dev->stats.tx_packets;
560		bi.data.cs.tx_errors = dev->stats.tx_errors;
561		bi.data.cs.rx_packets = dev->stats.rx_packets;
562		bi.data.cs.rx_errors = dev->stats.rx_errors;
563		break;		
564
565	case HDLCDRVCTL_OLDGETSTAT:
566		bi.data.ocs.ptt = hdlcdrv_ptt(s);
567		bi.data.ocs.dcd = s->hdlcrx.dcd;
568		bi.data.ocs.ptt_keyed = s->ptt_keyed;
569		break;		
570
571	case HDLCDRVCTL_CALIBRATE:
572		if(!capable(CAP_SYS_RAWIO))
573			return -EPERM;
 
 
 
 
574		s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
575		return 0;
576
577	case HDLCDRVCTL_GETSAMPLES:
578#ifndef HDLCDRV_DEBUG
579		return -EPERM;
580#else /* HDLCDRV_DEBUG */
581		if (s->bitbuf_channel.rd == s->bitbuf_channel.wr) 
582			return -EAGAIN;
583		bi.data.bits = 
584			s->bitbuf_channel.buffer[s->bitbuf_channel.rd];
585		s->bitbuf_channel.rd = (s->bitbuf_channel.rd+1) %
586			sizeof(s->bitbuf_channel.buffer);
587		break;
588#endif /* HDLCDRV_DEBUG */
589				
590	case HDLCDRVCTL_GETBITS:
591#ifndef HDLCDRV_DEBUG
592		return -EPERM;
593#else /* HDLCDRV_DEBUG */
594		if (s->bitbuf_hdlc.rd == s->bitbuf_hdlc.wr) 
595			return -EAGAIN;
596		bi.data.bits = 
597			s->bitbuf_hdlc.buffer[s->bitbuf_hdlc.rd];
598		s->bitbuf_hdlc.rd = (s->bitbuf_hdlc.rd+1) %
599			sizeof(s->bitbuf_hdlc.buffer);
600		break;		
601#endif /* HDLCDRV_DEBUG */
602
603	case HDLCDRVCTL_DRIVERNAME:
604		if (s->ops && s->ops->drvname) {
605			strncpy(bi.data.drivername, s->ops->drvname, 
606				sizeof(bi.data.drivername));
607			break;
608		}
609		bi.data.drivername[0] = '\0';
610		break;
611		
612	}
613	if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
614		return -EFAULT;
615	return 0;
616
617}
618
619/* --------------------------------------------------------------------- */
620
621static const struct net_device_ops hdlcdrv_netdev = {
622	.ndo_open	= hdlcdrv_open,
623	.ndo_stop	= hdlcdrv_close,
624	.ndo_start_xmit = hdlcdrv_send_packet,
625	.ndo_do_ioctl	= hdlcdrv_ioctl,
626	.ndo_set_mac_address = hdlcdrv_set_mac_address,
627};
628
629/*
630 * Initialize fields in hdlcdrv
631 */
632static void hdlcdrv_setup(struct net_device *dev)
633{
634	static const struct hdlcdrv_channel_params dflt_ch_params = { 
635		20, 2, 10, 40, 0 
636	};
637	struct hdlcdrv_state *s = netdev_priv(dev);
638
639	/*
640	 * initialize the hdlcdrv_state struct
641	 */
642	s->ch_params = dflt_ch_params;
643	s->ptt_keyed = 0;
644
645	spin_lock_init(&s->hdlcrx.hbuf.lock);
646	s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
647	s->hdlcrx.in_hdlc_rx = 0;
648	s->hdlcrx.rx_state = 0;
649	
650	spin_lock_init(&s->hdlctx.hbuf.lock);
651	s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
652	s->hdlctx.in_hdlc_tx = 0;
653	s->hdlctx.tx_state = 1;
654	s->hdlctx.numflags = 0;
655	s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
656	s->hdlctx.ptt = 0;
657	s->hdlctx.slotcnt = s->ch_params.slottime;
658	s->hdlctx.calibrate = 0;
659
660#ifdef HDLCDRV_DEBUG
661	s->bitbuf_channel.rd = s->bitbuf_channel.wr = 0;
662	s->bitbuf_channel.shreg = 0x80;
663
664	s->bitbuf_hdlc.rd = s->bitbuf_hdlc.wr = 0;
665	s->bitbuf_hdlc.shreg = 0x80;
666#endif /* HDLCDRV_DEBUG */
667
668
669	/* Fill in the fields of the device structure */
670
671	s->skb = NULL;
672	
673	dev->netdev_ops = &hdlcdrv_netdev;
674	dev->header_ops = &ax25_header_ops;
675	
676	dev->type = ARPHRD_AX25;           /* AF_AX25 device */
677	dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
678	dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
679	dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
680	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
681	memcpy(dev->dev_addr, &ax25_defaddr, AX25_ADDR_LEN);
682	dev->tx_queue_len = 16;
683}
684
685/* --------------------------------------------------------------------- */
686struct net_device *hdlcdrv_register(const struct hdlcdrv_ops *ops,
687				    unsigned int privsize, const char *ifname,
688				    unsigned int baseaddr, unsigned int irq, 
689				    unsigned int dma) 
690{
691	struct net_device *dev;
692	struct hdlcdrv_state *s;
693	int err;
694
695	BUG_ON(ops == NULL);
696
697	if (privsize < sizeof(struct hdlcdrv_state))
698		privsize = sizeof(struct hdlcdrv_state);
699
700	dev = alloc_netdev(privsize, ifname, hdlcdrv_setup);
701	if (!dev)
702		return ERR_PTR(-ENOMEM);
703
704	/*
705	 * initialize part of the hdlcdrv_state struct
706	 */
707	s = netdev_priv(dev);
708	s->magic = HDLCDRV_MAGIC;
709	s->ops = ops;
710	dev->base_addr = baseaddr;
711	dev->irq = irq;
712	dev->dma = dma;
713
714	err = register_netdev(dev);
715	if (err < 0) {
716		printk(KERN_WARNING "hdlcdrv: cannot register net "
717		       "device %s\n", dev->name);
718		free_netdev(dev);
719		dev = ERR_PTR(err);
720	}
721	return dev;
722}
723
724/* --------------------------------------------------------------------- */
725
726void hdlcdrv_unregister(struct net_device *dev) 
727{
728	struct hdlcdrv_state *s = netdev_priv(dev);
729
730	BUG_ON(s->magic != HDLCDRV_MAGIC);
731
732	if (s->opened && s->ops->close)
733		s->ops->close(dev);
734	unregister_netdev(dev);
735	
736	free_netdev(dev);
737}
738
739/* --------------------------------------------------------------------- */
740
741EXPORT_SYMBOL(hdlcdrv_receiver);
742EXPORT_SYMBOL(hdlcdrv_transmitter);
743EXPORT_SYMBOL(hdlcdrv_arbitrate);
744EXPORT_SYMBOL(hdlcdrv_register);
745EXPORT_SYMBOL(hdlcdrv_unregister);
746
747/* --------------------------------------------------------------------- */
748
749static int __init hdlcdrv_init_driver(void)
750{
751	printk(KERN_INFO "hdlcdrv: (C) 1996-2000 Thomas Sailer HB9JNX/AE4WA\n");
752	printk(KERN_INFO "hdlcdrv: version 0.8\n");
753	return 0;
754}
755
756/* --------------------------------------------------------------------- */
757
758static void __exit hdlcdrv_cleanup_driver(void)
759{
760	printk(KERN_INFO "hdlcdrv: cleanup\n");
761}
762
763/* --------------------------------------------------------------------- */
764
765MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
766MODULE_DESCRIPTION("Packet Radio network interface HDLC encoder/decoder");
767MODULE_LICENSE("GPL");
768module_init(hdlcdrv_init_driver);
769module_exit(hdlcdrv_cleanup_driver);
770
771/* --------------------------------------------------------------------- */