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1/*****************************************************************************/
2
3/*
4 *	baycom_epp.c  -- baycom epp radio modem driver.
5 *
6 *	Copyright (C) 1998-2000
7 *          Thomas Sailer (sailer@ife.ee.ethz.ch)
8 *
9 *	This program is free software; you can redistribute it and/or modify
10 *	it under the terms of the GNU General Public License as published by
11 *	the Free Software Foundation; either version 2 of the License, or
12 *	(at your option) any later version.
13 *
14 *	This program is distributed in the hope that it will be useful,
15 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
16 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 *	GNU General Public License for more details.
18 *
19 *	You should have received a copy of the GNU General Public License
20 *	along with this program; if not, write to the Free Software
21 *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 *
23 *  Please note that the GPL allows you to use the driver, NOT the radio.
24 *  In order to use the radio, you need a license from the communications
25 *  authority of your country.
26 *
27 *
28 *  History:
29 *   0.1  xx.xx.1998  Initial version by Matthias Welwarsky (dg2fef)
30 *   0.2  21.04.1998  Massive rework by Thomas Sailer
31 *                    Integrated FPGA EPP modem configuration routines
32 *   0.3  11.05.1998  Took FPGA config out and moved it into a separate program
33 *   0.4  26.07.1999  Adapted to new lowlevel parport driver interface
34 *   0.5  03.08.1999  adapt to Linus' new __setup/__initcall
35 *                    removed some pre-2.2 kernel compatibility cruft
36 *   0.6  10.08.1999  Check if parport can do SPP and is safe to access during interrupt contexts
37 *   0.7  12.02.2000  adapted to softnet driver interface
38 *
39 */
40
41/*****************************************************************************/
42
43#include <linux/crc-ccitt.h>
44#include <linux/module.h>
45#include <linux/kernel.h>
46#include <linux/init.h>
47#include <linux/sched.h>
48#include <linux/string.h>
49#include <linux/workqueue.h>
50#include <linux/fs.h>
51#include <linux/parport.h>
52#include <linux/if_arp.h>
53#include <linux/hdlcdrv.h>
54#include <linux/baycom.h>
55#include <linux/jiffies.h>
56#include <linux/random.h>
57#include <net/ax25.h>
58#include <asm/uaccess.h>
59
60/* --------------------------------------------------------------------- */
61
62#define BAYCOM_DEBUG
63#define BAYCOM_MAGIC 19730510
64
65/* --------------------------------------------------------------------- */
66
67static const char paranoia_str[] = KERN_ERR
68	"baycom_epp: bad magic number for hdlcdrv_state struct in routine %s\n";
69
70static const char bc_drvname[] = "baycom_epp";
71static const char bc_drvinfo[] = KERN_INFO "baycom_epp: (C) 1998-2000 Thomas Sailer, HB9JNX/AE4WA\n"
72"baycom_epp: version 0.7\n";
73
74/* --------------------------------------------------------------------- */
75
76#define NR_PORTS 4
77
78static struct net_device *baycom_device[NR_PORTS];
79
80/* --------------------------------------------------------------------- */
81
82/* EPP status register */
83#define EPP_DCDBIT      0x80
84#define EPP_PTTBIT      0x08
85#define EPP_NREF        0x01
86#define EPP_NRAEF       0x02
87#define EPP_NRHF        0x04
88#define EPP_NTHF        0x20
89#define EPP_NTAEF       0x10
90#define EPP_NTEF        EPP_PTTBIT
91
92/* EPP control register */
93#define EPP_TX_FIFO_ENABLE 0x10
94#define EPP_RX_FIFO_ENABLE 0x08
95#define EPP_MODEM_ENABLE   0x20
96#define EPP_LEDS           0xC0
97#define EPP_IRQ_ENABLE     0x10
98
99/* LPT registers */
100#define LPTREG_ECONTROL       0x402
101#define LPTREG_CONFIGB        0x401
102#define LPTREG_CONFIGA        0x400
103#define LPTREG_EPPDATA        0x004
104#define LPTREG_EPPADDR        0x003
105#define LPTREG_CONTROL        0x002
106#define LPTREG_STATUS         0x001
107#define LPTREG_DATA           0x000
108
109/* LPT control register */
110#define LPTCTRL_PROGRAM       0x04   /* 0 to reprogram */
111#define LPTCTRL_WRITE         0x01
112#define LPTCTRL_ADDRSTB       0x08
113#define LPTCTRL_DATASTB       0x02
114#define LPTCTRL_INTEN         0x10
115
116/* LPT status register */
117#define LPTSTAT_SHIFT_NINTR   6
118#define LPTSTAT_WAIT          0x80
119#define LPTSTAT_NINTR         (1<<LPTSTAT_SHIFT_NINTR)
120#define LPTSTAT_PE            0x20
121#define LPTSTAT_DONE          0x10
122#define LPTSTAT_NERROR        0x08
123#define LPTSTAT_EPPTIMEOUT    0x01
124
125/* LPT data register */
126#define LPTDATA_SHIFT_TDI     0
127#define LPTDATA_SHIFT_TMS     2
128#define LPTDATA_TDI           (1<<LPTDATA_SHIFT_TDI)
129#define LPTDATA_TCK           0x02
130#define LPTDATA_TMS           (1<<LPTDATA_SHIFT_TMS)
131#define LPTDATA_INITBIAS      0x80
132
133
134/* EPP modem config/status bits */
135#define EPP_DCDBIT            0x80
136#define EPP_PTTBIT            0x08
137#define EPP_RXEBIT            0x01
138#define EPP_RXAEBIT           0x02
139#define EPP_RXHFULL           0x04
140
141#define EPP_NTHF              0x20
142#define EPP_NTAEF             0x10
143#define EPP_NTEF              EPP_PTTBIT
144
145#define EPP_TX_FIFO_ENABLE    0x10
146#define EPP_RX_FIFO_ENABLE    0x08
147#define EPP_MODEM_ENABLE      0x20
148#define EPP_LEDS              0xC0
149#define EPP_IRQ_ENABLE        0x10
150
151/* Xilinx 4k JTAG instructions */
152#define XC4K_IRLENGTH   3
153#define XC4K_EXTEST     0
154#define XC4K_PRELOAD    1
155#define XC4K_CONFIGURE  5
156#define XC4K_BYPASS     7
157
158#define EPP_CONVENTIONAL  0
159#define EPP_FPGA          1
160#define EPP_FPGAEXTSTATUS 2
161
162#define TXBUFFER_SIZE     ((HDLCDRV_MAXFLEN*6/5)+8)
163
164/* ---------------------------------------------------------------------- */
165/*
166 * Information that need to be kept for each board.
167 */
168
169struct baycom_state {
170	int magic;
171
172        struct pardevice *pdev;
173	struct net_device *dev;
174	unsigned int work_running;
175	struct delayed_work run_work;
176	unsigned int modem;
177	unsigned int bitrate;
178	unsigned char stat;
179
180	struct {
181		unsigned int intclk;
182		unsigned int fclk;
183		unsigned int bps;
184		unsigned int extmodem;
185		unsigned int loopback;
186	} cfg;
187
188        struct hdlcdrv_channel_params ch_params;
189
190        struct {
191		unsigned int bitbuf, bitstream, numbits, state;
192		unsigned char *bufptr;
193		int bufcnt;
194		unsigned char buf[TXBUFFER_SIZE];
195        } hdlcrx;
196
197        struct {
198		int calibrate;
199                int slotcnt;
200		int flags;
201		enum { tx_idle = 0, tx_keyup, tx_data, tx_tail } state;
202		unsigned char *bufptr;
203		int bufcnt;
204		unsigned char buf[TXBUFFER_SIZE];
205        } hdlctx;
206
207	unsigned int ptt_keyed;
208	struct sk_buff *skb;  /* next transmit packet  */
209
210#ifdef BAYCOM_DEBUG
211	struct debug_vals {
212		unsigned long last_jiffies;
213		unsigned cur_intcnt;
214		unsigned last_intcnt;
215		int cur_pllcorr;
216		int last_pllcorr;
217		unsigned int mod_cycles;
218		unsigned int demod_cycles;
219	} debug_vals;
220#endif /* BAYCOM_DEBUG */
221};
222
223/* --------------------------------------------------------------------- */
224
225#define KISS_VERBOSE
226
227/* --------------------------------------------------------------------- */
228
229#define PARAM_TXDELAY   1
230#define PARAM_PERSIST   2
231#define PARAM_SLOTTIME  3
232#define PARAM_TXTAIL    4
233#define PARAM_FULLDUP   5
234#define PARAM_HARDWARE  6
235#define PARAM_RETURN    255
236
237/* --------------------------------------------------------------------- */
238/*
239 * the CRC routines are stolen from WAMPES
240 * by Dieter Deyke
241 */
242
243
244/*---------------------------------------------------------------------------*/
245
246#if 0
247static inline void append_crc_ccitt(unsigned char *buffer, int len)
248{
249 	unsigned int crc = 0xffff;
250
251	for (;len>0;len--)
252		crc = (crc >> 8) ^ crc_ccitt_table[(crc ^ *buffer++) & 0xff];
253	crc ^= 0xffff;
254	*buffer++ = crc;
255	*buffer++ = crc >> 8;
256}
257#endif
258
259/*---------------------------------------------------------------------------*/
260
261static inline int check_crc_ccitt(const unsigned char *buf, int cnt)
262{
263	return (crc_ccitt(0xffff, buf, cnt) & 0xffff) == 0xf0b8;
264}
265
266/*---------------------------------------------------------------------------*/
267
268static inline int calc_crc_ccitt(const unsigned char *buf, int cnt)
269{
270	return (crc_ccitt(0xffff, buf, cnt) ^ 0xffff) & 0xffff;
271}
272
273/* ---------------------------------------------------------------------- */
274
275#define tenms_to_flags(bc,tenms) ((tenms * bc->bitrate) / 800)
276
277/* --------------------------------------------------------------------- */
278
279static inline void baycom_int_freq(struct baycom_state *bc)
280{
281#ifdef BAYCOM_DEBUG
282	unsigned long cur_jiffies = jiffies;
283	/*
284	 * measure the interrupt frequency
285	 */
286	bc->debug_vals.cur_intcnt++;
287	if (time_after_eq(cur_jiffies, bc->debug_vals.last_jiffies + HZ)) {
288		bc->debug_vals.last_jiffies = cur_jiffies;
289		bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
290		bc->debug_vals.cur_intcnt = 0;
291		bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
292		bc->debug_vals.cur_pllcorr = 0;
293	}
294#endif /* BAYCOM_DEBUG */
295}
296
297/* ---------------------------------------------------------------------- */
298/*
299 *    eppconfig_path should be setable  via /proc/sys.
300 */
301
302static char eppconfig_path[256] = "/usr/sbin/eppfpga";
303
304static char *envp[] = { "HOME=/", "TERM=linux", "PATH=/usr/bin:/bin", NULL };
305
306/* eppconfig: called during ifconfig up to configure the modem */
307static int eppconfig(struct baycom_state *bc)
308{
309	char modearg[256];
310	char portarg[16];
311        char *argv[] = { eppconfig_path, "-s", "-p", portarg, "-m", modearg,
312			 NULL };
313
314	/* set up arguments */
315	sprintf(modearg, "%sclk,%smodem,fclk=%d,bps=%d,divider=%d%s,extstat",
316		bc->cfg.intclk ? "int" : "ext",
317		bc->cfg.extmodem ? "ext" : "int", bc->cfg.fclk, bc->cfg.bps,
318		(bc->cfg.fclk + 8 * bc->cfg.bps) / (16 * bc->cfg.bps),
319		bc->cfg.loopback ? ",loopback" : "");
320	sprintf(portarg, "%ld", bc->pdev->port->base);
321	printk(KERN_DEBUG "%s: %s -s -p %s -m %s\n", bc_drvname, eppconfig_path, portarg, modearg);
322
323	return call_usermodehelper(eppconfig_path, argv, envp, UMH_WAIT_PROC);
324}
325
326/* ---------------------------------------------------------------------- */
327
328static inline void do_kiss_params(struct baycom_state *bc,
329				  unsigned char *data, unsigned long len)
330{
331
332#ifdef KISS_VERBOSE
333#define PKP(a,b) printk(KERN_INFO "baycomm_epp: channel params: " a "\n", b)
334#else /* KISS_VERBOSE */
335#define PKP(a,b)
336#endif /* KISS_VERBOSE */
337
338	if (len < 2)
339		return;
340	switch(data[0]) {
341	case PARAM_TXDELAY:
342		bc->ch_params.tx_delay = data[1];
343		PKP("TX delay = %ums", 10 * bc->ch_params.tx_delay);
344		break;
345	case PARAM_PERSIST:
346		bc->ch_params.ppersist = data[1];
347		PKP("p persistence = %u", bc->ch_params.ppersist);
348		break;
349	case PARAM_SLOTTIME:
350		bc->ch_params.slottime = data[1];
351		PKP("slot time = %ums", bc->ch_params.slottime);
352		break;
353	case PARAM_TXTAIL:
354		bc->ch_params.tx_tail = data[1];
355		PKP("TX tail = %ums", bc->ch_params.tx_tail);
356		break;
357	case PARAM_FULLDUP:
358		bc->ch_params.fulldup = !!data[1];
359		PKP("%s duplex", bc->ch_params.fulldup ? "full" : "half");
360		break;
361	default:
362		break;
363	}
364#undef PKP
365}
366
367/* --------------------------------------------------------------------- */
368
369static void encode_hdlc(struct baycom_state *bc)
370{
371	struct sk_buff *skb;
372	unsigned char *wp, *bp;
373	int pkt_len;
374        unsigned bitstream, notbitstream, bitbuf, numbit, crc;
375	unsigned char crcarr[2];
376	int j;
377
378	if (bc->hdlctx.bufcnt > 0)
379		return;
380	skb = bc->skb;
381	if (!skb)
382		return;
383	bc->skb = NULL;
384	pkt_len = skb->len-1; /* strip KISS byte */
385	wp = bc->hdlctx.buf;
386	bp = skb->data+1;
387	crc = calc_crc_ccitt(bp, pkt_len);
388	crcarr[0] = crc;
389	crcarr[1] = crc >> 8;
390	*wp++ = 0x7e;
391	bitstream = bitbuf = numbit = 0;
392	while (pkt_len > -2) {
393		bitstream >>= 8;
394		bitstream |= ((unsigned int)*bp) << 8;
395		bitbuf |= ((unsigned int)*bp) << numbit;
396		notbitstream = ~bitstream;
397		bp++;
398		pkt_len--;
399		if (!pkt_len)
400			bp = crcarr;
401		for (j = 0; j < 8; j++)
402			if (unlikely(!(notbitstream & (0x1f0 << j)))) {
403				bitstream &= ~(0x100 << j);
404 				bitbuf = (bitbuf & (((2 << j) << numbit) - 1)) |
405					((bitbuf & ~(((2 << j) << numbit) - 1)) << 1);
406				numbit++;
407				notbitstream = ~bitstream;
408			}
409		numbit += 8;
410		while (numbit >= 8) {
411			*wp++ = bitbuf;
412			bitbuf >>= 8;
413			numbit -= 8;
414		}
415	}
416	bitbuf |= 0x7e7e << numbit;
417	numbit += 16;
418	while (numbit >= 8) {
419		*wp++ = bitbuf;
420		bitbuf >>= 8;
421		numbit -= 8;
422	}
423	bc->hdlctx.bufptr = bc->hdlctx.buf;
424	bc->hdlctx.bufcnt = wp - bc->hdlctx.buf;
425	dev_kfree_skb(skb);
426	bc->dev->stats.tx_packets++;
427}
428
429/* ---------------------------------------------------------------------- */
430
431static int transmit(struct baycom_state *bc, int cnt, unsigned char stat)
432{
433	struct parport *pp = bc->pdev->port;
434	unsigned char tmp[128];
435	int i, j;
436
437	if (bc->hdlctx.state == tx_tail && !(stat & EPP_PTTBIT))
438		bc->hdlctx.state = tx_idle;
439	if (bc->hdlctx.state == tx_idle && bc->hdlctx.calibrate <= 0) {
440		if (bc->hdlctx.bufcnt <= 0)
441			encode_hdlc(bc);
442		if (bc->hdlctx.bufcnt <= 0)
443			return 0;
444		if (!bc->ch_params.fulldup) {
445			if (!(stat & EPP_DCDBIT)) {
446				bc->hdlctx.slotcnt = bc->ch_params.slottime;
447				return 0;
448			}
449			if ((--bc->hdlctx.slotcnt) > 0)
450				return 0;
451			bc->hdlctx.slotcnt = bc->ch_params.slottime;
452			if ((prandom_u32() % 256) > bc->ch_params.ppersist)
453				return 0;
454		}
455	}
456	if (bc->hdlctx.state == tx_idle && bc->hdlctx.bufcnt > 0) {
457		bc->hdlctx.state = tx_keyup;
458		bc->hdlctx.flags = tenms_to_flags(bc, bc->ch_params.tx_delay);
459		bc->ptt_keyed++;
460	}
461	while (cnt > 0) {
462		switch (bc->hdlctx.state) {
463		case tx_keyup:
464			i = min_t(int, cnt, bc->hdlctx.flags);
465			cnt -= i;
466			bc->hdlctx.flags -= i;
467			if (bc->hdlctx.flags <= 0)
468				bc->hdlctx.state = tx_data;
469			memset(tmp, 0x7e, sizeof(tmp));
470			while (i > 0) {
471				j = (i > sizeof(tmp)) ? sizeof(tmp) : i;
472				if (j != pp->ops->epp_write_data(pp, tmp, j, 0))
473					return -1;
474				i -= j;
475			}
476			break;
477
478		case tx_data:
479			if (bc->hdlctx.bufcnt <= 0) {
480				encode_hdlc(bc);
481				if (bc->hdlctx.bufcnt <= 0) {
482					bc->hdlctx.state = tx_tail;
483					bc->hdlctx.flags = tenms_to_flags(bc, bc->ch_params.tx_tail);
484					break;
485				}
486			}
487			i = min_t(int, cnt, bc->hdlctx.bufcnt);
488			bc->hdlctx.bufcnt -= i;
489			cnt -= i;
490			if (i != pp->ops->epp_write_data(pp, bc->hdlctx.bufptr, i, 0))
491					return -1;
492			bc->hdlctx.bufptr += i;
493			break;
494
495		case tx_tail:
496			encode_hdlc(bc);
497			if (bc->hdlctx.bufcnt > 0) {
498				bc->hdlctx.state = tx_data;
499				break;
500			}
501			i = min_t(int, cnt, bc->hdlctx.flags);
502			if (i) {
503				cnt -= i;
504				bc->hdlctx.flags -= i;
505				memset(tmp, 0x7e, sizeof(tmp));
506				while (i > 0) {
507					j = (i > sizeof(tmp)) ? sizeof(tmp) : i;
508					if (j != pp->ops->epp_write_data(pp, tmp, j, 0))
509						return -1;
510					i -= j;
511				}
512				break;
513			}
514
515		default:  /* fall through */
516			if (bc->hdlctx.calibrate <= 0)
517				return 0;
518			i = min_t(int, cnt, bc->hdlctx.calibrate);
519			cnt -= i;
520			bc->hdlctx.calibrate -= i;
521			memset(tmp, 0, sizeof(tmp));
522			while (i > 0) {
523				j = (i > sizeof(tmp)) ? sizeof(tmp) : i;
524				if (j != pp->ops->epp_write_data(pp, tmp, j, 0))
525					return -1;
526				i -= j;
527			}
528			break;
529		}
530	}
531	return 0;
532}
533
534/* ---------------------------------------------------------------------- */
535
536static void do_rxpacket(struct net_device *dev)
537{
538	struct baycom_state *bc = netdev_priv(dev);
539	struct sk_buff *skb;
540	unsigned char *cp;
541	unsigned pktlen;
542
543	if (bc->hdlcrx.bufcnt < 4)
544		return;
545	if (!check_crc_ccitt(bc->hdlcrx.buf, bc->hdlcrx.bufcnt))
546		return;
547	pktlen = bc->hdlcrx.bufcnt-2+1; /* KISS kludge */
548	if (!(skb = dev_alloc_skb(pktlen))) {
549		printk("%s: memory squeeze, dropping packet\n", dev->name);
550		dev->stats.rx_dropped++;
551		return;
552	}
553	cp = skb_put(skb, pktlen);
554	*cp++ = 0; /* KISS kludge */
555	memcpy(cp, bc->hdlcrx.buf, pktlen - 1);
556	skb->protocol = ax25_type_trans(skb, dev);
557	netif_rx(skb);
558	dev->stats.rx_packets++;
559}
560
561static int receive(struct net_device *dev, int cnt)
562{
563	struct baycom_state *bc = netdev_priv(dev);
564	struct parport *pp = bc->pdev->port;
565        unsigned int bitbuf, notbitstream, bitstream, numbits, state;
566	unsigned char tmp[128];
567        unsigned char *cp;
568	int cnt2, ret = 0;
569	int j;
570
571        numbits = bc->hdlcrx.numbits;
572	state = bc->hdlcrx.state;
573	bitstream = bc->hdlcrx.bitstream;
574	bitbuf = bc->hdlcrx.bitbuf;
575	while (cnt > 0) {
576		cnt2 = (cnt > sizeof(tmp)) ? sizeof(tmp) : cnt;
577		cnt -= cnt2;
578		if (cnt2 != pp->ops->epp_read_data(pp, tmp, cnt2, 0)) {
579			ret = -1;
580			break;
581		}
582		cp = tmp;
583		for (; cnt2 > 0; cnt2--, cp++) {
584			bitstream >>= 8;
585			bitstream |= (*cp) << 8;
586			bitbuf >>= 8;
587			bitbuf |= (*cp) << 8;
588			numbits += 8;
589			notbitstream = ~bitstream;
590			for (j = 0; j < 8; j++) {
591
592				/* flag or abort */
593			        if (unlikely(!(notbitstream & (0x0fc << j)))) {
594
595					/* abort received */
596					if (!(notbitstream & (0x1fc << j)))
597						state = 0;
598
599					/* flag received */
600					else if ((bitstream & (0x1fe << j)) == (0x0fc << j)) {
601						if (state)
602							do_rxpacket(dev);
603						bc->hdlcrx.bufcnt = 0;
604						bc->hdlcrx.bufptr = bc->hdlcrx.buf;
605						state = 1;
606						numbits = 7-j;
607					}
608				}
609
610				/* stuffed bit */
611				else if (unlikely((bitstream & (0x1f8 << j)) == (0xf8 << j))) {
612					numbits--;
613					bitbuf = (bitbuf & ((~0xff) << j)) | ((bitbuf & ~((~0xff) << j)) << 1);
614					}
615				}
616			while (state && numbits >= 8) {
617				if (bc->hdlcrx.bufcnt >= TXBUFFER_SIZE) {
618					state = 0;
619				} else {
620					*(bc->hdlcrx.bufptr)++ = bitbuf >> (16-numbits);
621					bc->hdlcrx.bufcnt++;
622					numbits -= 8;
623				}
624			}
625		}
626	}
627        bc->hdlcrx.numbits = numbits;
628	bc->hdlcrx.state = state;
629	bc->hdlcrx.bitstream = bitstream;
630	bc->hdlcrx.bitbuf = bitbuf;
631	return ret;
632}
633
634/* --------------------------------------------------------------------- */
635
636#ifdef __i386__
637#include <asm/msr.h>
638#define GETTICK(x)                                                \
639({                                                                \
640	if (cpu_has_tsc)                                          \
641		rdtscl(x);                                        \
642})
643#else /* __i386__ */
644#define GETTICK(x)
645#endif /* __i386__ */
646
647static void epp_bh(struct work_struct *work)
648{
649	struct net_device *dev;
650	struct baycom_state *bc;
651	struct parport *pp;
652	unsigned char stat;
653	unsigned char tmp[2];
654	unsigned int time1 = 0, time2 = 0, time3 = 0;
655	int cnt, cnt2;
656
657	bc = container_of(work, struct baycom_state, run_work.work);
658	dev = bc->dev;
659	if (!bc->work_running)
660		return;
661	baycom_int_freq(bc);
662	pp = bc->pdev->port;
663	/* update status */
664	if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
665		goto epptimeout;
666	bc->stat = stat;
667	bc->debug_vals.last_pllcorr = stat;
668	GETTICK(time1);
669	if (bc->modem == EPP_FPGAEXTSTATUS) {
670		/* get input count */
671		tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE|1;
672		if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
673			goto epptimeout;
674		if (pp->ops->epp_read_addr(pp, tmp, 2, 0) != 2)
675			goto epptimeout;
676		cnt = tmp[0] | (tmp[1] << 8);
677		cnt &= 0x7fff;
678		/* get output count */
679		tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE|2;
680		if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
681			goto epptimeout;
682		if (pp->ops->epp_read_addr(pp, tmp, 2, 0) != 2)
683			goto epptimeout;
684		cnt2 = tmp[0] | (tmp[1] << 8);
685		cnt2 = 16384 - (cnt2 & 0x7fff);
686		/* return to normal */
687		tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE;
688		if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
689			goto epptimeout;
690		if (transmit(bc, cnt2, stat))
691			goto epptimeout;
692		GETTICK(time2);
693		if (receive(dev, cnt))
694			goto epptimeout;
695		if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
696			goto epptimeout;
697		bc->stat = stat;
698	} else {
699		/* try to tx */
700		switch (stat & (EPP_NTAEF|EPP_NTHF)) {
701		case EPP_NTHF:
702			cnt = 2048 - 256;
703			break;
704
705		case EPP_NTAEF:
706			cnt = 2048 - 1793;
707			break;
708
709		case 0:
710			cnt = 0;
711			break;
712
713		default:
714			cnt = 2048 - 1025;
715			break;
716		}
717		if (transmit(bc, cnt, stat))
718			goto epptimeout;
719		GETTICK(time2);
720		/* do receiver */
721		while ((stat & (EPP_NRAEF|EPP_NRHF)) != EPP_NRHF) {
722			switch (stat & (EPP_NRAEF|EPP_NRHF)) {
723			case EPP_NRAEF:
724				cnt = 1025;
725				break;
726
727			case 0:
728				cnt = 1793;
729				break;
730
731			default:
732				cnt = 256;
733				break;
734			}
735			if (receive(dev, cnt))
736				goto epptimeout;
737			if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
738				goto epptimeout;
739		}
740		cnt = 0;
741		if (bc->bitrate < 50000)
742			cnt = 256;
743		else if (bc->bitrate < 100000)
744			cnt = 128;
745		while (cnt > 0 && stat & EPP_NREF) {
746			if (receive(dev, 1))
747				goto epptimeout;
748			cnt--;
749			if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
750				goto epptimeout;
751		}
752	}
753	GETTICK(time3);
754#ifdef BAYCOM_DEBUG
755	bc->debug_vals.mod_cycles = time2 - time1;
756	bc->debug_vals.demod_cycles = time3 - time2;
757#endif /* BAYCOM_DEBUG */
758	schedule_delayed_work(&bc->run_work, 1);
759	if (!bc->skb)
760		netif_wake_queue(dev);
761	return;
762 epptimeout:
763	printk(KERN_ERR "%s: EPP timeout!\n", bc_drvname);
764}
765
766/* ---------------------------------------------------------------------- */
767/*
768 * ===================== network driver interface =========================
769 */
770
771static int baycom_send_packet(struct sk_buff *skb, struct net_device *dev)
772{
773	struct baycom_state *bc = netdev_priv(dev);
774
775	if (skb->data[0] != 0) {
776		do_kiss_params(bc, skb->data, skb->len);
777		dev_kfree_skb(skb);
778		return NETDEV_TX_OK;
779	}
780	if (bc->skb)
781		return NETDEV_TX_LOCKED;
782	/* strip KISS byte */
783	if (skb->len >= HDLCDRV_MAXFLEN+1 || skb->len < 3) {
784		dev_kfree_skb(skb);
785		return NETDEV_TX_OK;
786	}
787	netif_stop_queue(dev);
788	bc->skb = skb;
789	return NETDEV_TX_OK;
790}
791
792/* --------------------------------------------------------------------- */
793
794static int baycom_set_mac_address(struct net_device *dev, void *addr)
795{
796	struct sockaddr *sa = (struct sockaddr *)addr;
797
798	/* addr is an AX.25 shifted ASCII mac address */
799	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
800	return 0;
801}
802
803/* --------------------------------------------------------------------- */
804
805static void epp_wakeup(void *handle)
806{
807        struct net_device *dev = (struct net_device *)handle;
808        struct baycom_state *bc = netdev_priv(dev);
809
810        printk(KERN_DEBUG "baycom_epp: %s: why am I being woken up?\n", dev->name);
811        if (!parport_claim(bc->pdev))
812                printk(KERN_DEBUG "baycom_epp: %s: I'm broken.\n", dev->name);
813}
814
815/* --------------------------------------------------------------------- */
816
817/*
818 * Open/initialize the board. This is called (in the current kernel)
819 * sometime after booting when the 'ifconfig' program is run.
820 *
821 * This routine should set everything up anew at each open, even
822 * registers that "should" only need to be set once at boot, so that
823 * there is non-reboot way to recover if something goes wrong.
824 */
825
826static int epp_open(struct net_device *dev)
827{
828	struct baycom_state *bc = netdev_priv(dev);
829        struct parport *pp = parport_find_base(dev->base_addr);
830	unsigned int i, j;
831	unsigned char tmp[128];
832	unsigned char stat;
833	unsigned long tstart;
834
835        if (!pp) {
836                printk(KERN_ERR "%s: parport at 0x%lx unknown\n", bc_drvname, dev->base_addr);
837                return -ENXIO;
838        }
839#if 0
840        if (pp->irq < 0) {
841                printk(KERN_ERR "%s: parport at 0x%lx has no irq\n", bc_drvname, pp->base);
842		parport_put_port(pp);
843                return -ENXIO;
844        }
845#endif
846	if ((~pp->modes) & (PARPORT_MODE_TRISTATE | PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT)) {
847                printk(KERN_ERR "%s: parport at 0x%lx cannot be used\n",
848		       bc_drvname, pp->base);
849		parport_put_port(pp);
850                return -EIO;
851	}
852	memset(&bc->modem, 0, sizeof(bc->modem));
853        bc->pdev = parport_register_device(pp, dev->name, NULL, epp_wakeup,
854					   NULL, PARPORT_DEV_EXCL, dev);
855	parport_put_port(pp);
856        if (!bc->pdev) {
857                printk(KERN_ERR "%s: cannot register parport at 0x%lx\n", bc_drvname, pp->base);
858                return -ENXIO;
859        }
860        if (parport_claim(bc->pdev)) {
861                printk(KERN_ERR "%s: parport at 0x%lx busy\n", bc_drvname, pp->base);
862                parport_unregister_device(bc->pdev);
863                return -EBUSY;
864        }
865        dev->irq = /*pp->irq*/ 0;
866	INIT_DELAYED_WORK(&bc->run_work, epp_bh);
867	bc->work_running = 1;
868	bc->modem = EPP_CONVENTIONAL;
869	if (eppconfig(bc))
870		printk(KERN_INFO "%s: no FPGA detected, assuming conventional EPP modem\n", bc_drvname);
871	else
872		bc->modem = /*EPP_FPGA*/ EPP_FPGAEXTSTATUS;
873	parport_write_control(pp, LPTCTRL_PROGRAM); /* prepare EPP mode; we aren't using interrupts */
874	/* reset the modem */
875	tmp[0] = 0;
876	tmp[1] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE;
877	if (pp->ops->epp_write_addr(pp, tmp, 2, 0) != 2)
878		goto epptimeout;
879	/* autoprobe baud rate */
880	tstart = jiffies;
881	i = 0;
882	while (time_before(jiffies, tstart + HZ/3)) {
883		if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
884			goto epptimeout;
885		if ((stat & (EPP_NRAEF|EPP_NRHF)) == EPP_NRHF) {
886			schedule();
887			continue;
888		}
889		if (pp->ops->epp_read_data(pp, tmp, 128, 0) != 128)
890			goto epptimeout;
891		if (pp->ops->epp_read_data(pp, tmp, 128, 0) != 128)
892			goto epptimeout;
893		i += 256;
894	}
895	for (j = 0; j < 256; j++) {
896		if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
897			goto epptimeout;
898		if (!(stat & EPP_NREF))
899			break;
900		if (pp->ops->epp_read_data(pp, tmp, 1, 0) != 1)
901			goto epptimeout;
902		i++;
903	}
904	tstart = jiffies - tstart;
905	bc->bitrate = i * (8 * HZ) / tstart;
906	j = 1;
907	i = bc->bitrate >> 3;
908	while (j < 7 && i > 150) {
909		j++;
910		i >>= 1;
911	}
912	printk(KERN_INFO "%s: autoprobed bitrate: %d  int divider: %d  int rate: %d\n",
913	       bc_drvname, bc->bitrate, j, bc->bitrate >> (j+2));
914	tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE/*|j*/;
915	if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
916		goto epptimeout;
917	/*
918	 * initialise hdlc variables
919	 */
920	bc->hdlcrx.state = 0;
921	bc->hdlcrx.numbits = 0;
922	bc->hdlctx.state = tx_idle;
923	bc->hdlctx.bufcnt = 0;
924	bc->hdlctx.slotcnt = bc->ch_params.slottime;
925	bc->hdlctx.calibrate = 0;
926	/* start the bottom half stuff */
927	schedule_delayed_work(&bc->run_work, 1);
928	netif_start_queue(dev);
929	return 0;
930
931 epptimeout:
932	printk(KERN_ERR "%s: epp timeout during bitrate probe\n", bc_drvname);
933	parport_write_control(pp, 0); /* reset the adapter */
934        parport_release(bc->pdev);
935        parport_unregister_device(bc->pdev);
936	return -EIO;
937}
938
939/* --------------------------------------------------------------------- */
940
941static int epp_close(struct net_device *dev)
942{
943	struct baycom_state *bc = netdev_priv(dev);
944	struct parport *pp = bc->pdev->port;
945	unsigned char tmp[1];
946
947	bc->work_running = 0;
948	cancel_delayed_work_sync(&bc->run_work);
949	bc->stat = EPP_DCDBIT;
950	tmp[0] = 0;
951	pp->ops->epp_write_addr(pp, tmp, 1, 0);
952	parport_write_control(pp, 0); /* reset the adapter */
953        parport_release(bc->pdev);
954        parport_unregister_device(bc->pdev);
955	if (bc->skb)
956		dev_kfree_skb(bc->skb);
957	bc->skb = NULL;
958	printk(KERN_INFO "%s: close epp at iobase 0x%lx irq %u\n",
959	       bc_drvname, dev->base_addr, dev->irq);
960	return 0;
961}
962
963/* --------------------------------------------------------------------- */
964
965static int baycom_setmode(struct baycom_state *bc, const char *modestr)
966{
967	const char *cp;
968
969	if (strstr(modestr,"intclk"))
970		bc->cfg.intclk = 1;
971	if (strstr(modestr,"extclk"))
972		bc->cfg.intclk = 0;
973	if (strstr(modestr,"intmodem"))
974		bc->cfg.extmodem = 0;
975	if (strstr(modestr,"extmodem"))
976		bc->cfg.extmodem = 1;
977	if (strstr(modestr,"noloopback"))
978		bc->cfg.loopback = 0;
979	if (strstr(modestr,"loopback"))
980		bc->cfg.loopback = 1;
981	if ((cp = strstr(modestr,"fclk="))) {
982		bc->cfg.fclk = simple_strtoul(cp+5, NULL, 0);
983		if (bc->cfg.fclk < 1000000)
984			bc->cfg.fclk = 1000000;
985		if (bc->cfg.fclk > 25000000)
986			bc->cfg.fclk = 25000000;
987	}
988	if ((cp = strstr(modestr,"bps="))) {
989		bc->cfg.bps = simple_strtoul(cp+4, NULL, 0);
990		if (bc->cfg.bps < 1000)
991			bc->cfg.bps = 1000;
992		if (bc->cfg.bps > 1500000)
993			bc->cfg.bps = 1500000;
994	}
995	return 0;
996}
997
998/* --------------------------------------------------------------------- */
999
1000static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1001{
1002	struct baycom_state *bc = netdev_priv(dev);
1003	struct hdlcdrv_ioctl hi;
1004
1005	if (cmd != SIOCDEVPRIVATE)
1006		return -ENOIOCTLCMD;
1007
1008	if (copy_from_user(&hi, ifr->ifr_data, sizeof(hi)))
1009		return -EFAULT;
1010	switch (hi.cmd) {
1011	default:
1012		return -ENOIOCTLCMD;
1013
1014	case HDLCDRVCTL_GETCHANNELPAR:
1015		hi.data.cp.tx_delay = bc->ch_params.tx_delay;
1016		hi.data.cp.tx_tail = bc->ch_params.tx_tail;
1017		hi.data.cp.slottime = bc->ch_params.slottime;
1018		hi.data.cp.ppersist = bc->ch_params.ppersist;
1019		hi.data.cp.fulldup = bc->ch_params.fulldup;
1020		break;
1021
1022	case HDLCDRVCTL_SETCHANNELPAR:
1023		if (!capable(CAP_NET_ADMIN))
1024			return -EACCES;
1025		bc->ch_params.tx_delay = hi.data.cp.tx_delay;
1026		bc->ch_params.tx_tail = hi.data.cp.tx_tail;
1027		bc->ch_params.slottime = hi.data.cp.slottime;
1028		bc->ch_params.ppersist = hi.data.cp.ppersist;
1029		bc->ch_params.fulldup = hi.data.cp.fulldup;
1030		bc->hdlctx.slotcnt = 1;
1031		return 0;
1032
1033	case HDLCDRVCTL_GETMODEMPAR:
1034		hi.data.mp.iobase = dev->base_addr;
1035		hi.data.mp.irq = dev->irq;
1036		hi.data.mp.dma = dev->dma;
1037		hi.data.mp.dma2 = 0;
1038		hi.data.mp.seriobase = 0;
1039		hi.data.mp.pariobase = 0;
1040		hi.data.mp.midiiobase = 0;
1041		break;
1042
1043	case HDLCDRVCTL_SETMODEMPAR:
1044		if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
1045			return -EACCES;
1046		dev->base_addr = hi.data.mp.iobase;
1047		dev->irq = /*hi.data.mp.irq*/0;
1048		dev->dma = /*hi.data.mp.dma*/0;
1049		return 0;
1050
1051	case HDLCDRVCTL_GETSTAT:
1052		hi.data.cs.ptt = !!(bc->stat & EPP_PTTBIT);
1053		hi.data.cs.dcd = !(bc->stat & EPP_DCDBIT);
1054		hi.data.cs.ptt_keyed = bc->ptt_keyed;
1055		hi.data.cs.tx_packets = dev->stats.tx_packets;
1056		hi.data.cs.tx_errors = dev->stats.tx_errors;
1057		hi.data.cs.rx_packets = dev->stats.rx_packets;
1058		hi.data.cs.rx_errors = dev->stats.rx_errors;
1059		break;
1060
1061	case HDLCDRVCTL_OLDGETSTAT:
1062		hi.data.ocs.ptt = !!(bc->stat & EPP_PTTBIT);
1063		hi.data.ocs.dcd = !(bc->stat & EPP_DCDBIT);
1064		hi.data.ocs.ptt_keyed = bc->ptt_keyed;
1065		break;
1066
1067	case HDLCDRVCTL_CALIBRATE:
1068		if (!capable(CAP_SYS_RAWIO))
1069			return -EACCES;
1070		bc->hdlctx.calibrate = hi.data.calibrate * bc->bitrate / 8;
1071		return 0;
1072
1073	case HDLCDRVCTL_DRIVERNAME:
1074		strncpy(hi.data.drivername, "baycom_epp", sizeof(hi.data.drivername));
1075		break;
1076
1077	case HDLCDRVCTL_GETMODE:
1078		sprintf(hi.data.modename, "%sclk,%smodem,fclk=%d,bps=%d%s",
1079			bc->cfg.intclk ? "int" : "ext",
1080			bc->cfg.extmodem ? "ext" : "int", bc->cfg.fclk, bc->cfg.bps,
1081			bc->cfg.loopback ? ",loopback" : "");
1082		break;
1083
1084	case HDLCDRVCTL_SETMODE:
1085		if (!capable(CAP_NET_ADMIN) || netif_running(dev))
1086			return -EACCES;
1087		hi.data.modename[sizeof(hi.data.modename)-1] = '\0';
1088		return baycom_setmode(bc, hi.data.modename);
1089
1090	case HDLCDRVCTL_MODELIST:
1091		strncpy(hi.data.modename, "intclk,extclk,intmodem,extmodem,divider=x",
1092			sizeof(hi.data.modename));
1093		break;
1094
1095	case HDLCDRVCTL_MODEMPARMASK:
1096		return HDLCDRV_PARMASK_IOBASE;
1097
1098	}
1099	if (copy_to_user(ifr->ifr_data, &hi, sizeof(hi)))
1100		return -EFAULT;
1101	return 0;
1102}
1103
1104/* --------------------------------------------------------------------- */
1105
1106static const struct net_device_ops baycom_netdev_ops = {
1107	.ndo_open	     = epp_open,
1108	.ndo_stop	     = epp_close,
1109	.ndo_do_ioctl	     = baycom_ioctl,
1110	.ndo_start_xmit      = baycom_send_packet,
1111	.ndo_set_mac_address = baycom_set_mac_address,
1112};
1113
1114/*
1115 * Check for a network adaptor of this type, and return '0' if one exists.
1116 * If dev->base_addr == 0, probe all likely locations.
1117 * If dev->base_addr == 1, always return failure.
1118 * If dev->base_addr == 2, allocate space for the device and return success
1119 * (detachable devices only).
1120 */
1121static void baycom_probe(struct net_device *dev)
1122{
1123	const struct hdlcdrv_channel_params dflt_ch_params = {
1124		20, 2, 10, 40, 0
1125	};
1126	struct baycom_state *bc;
1127
1128	/*
1129	 * not a real probe! only initialize data structures
1130	 */
1131	bc = netdev_priv(dev);
1132	/*
1133	 * initialize the baycom_state struct
1134	 */
1135	bc->ch_params = dflt_ch_params;
1136	bc->ptt_keyed = 0;
1137
1138	/*
1139	 * initialize the device struct
1140	 */
1141
1142	/* Fill in the fields of the device structure */
1143	bc->skb = NULL;
1144
1145	dev->netdev_ops = &baycom_netdev_ops;
1146	dev->header_ops = &ax25_header_ops;
1147
1148	dev->type = ARPHRD_AX25;           /* AF_AX25 device */
1149	dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
1150	dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
1151	dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
1152	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
1153	memcpy(dev->dev_addr, &null_ax25_address, AX25_ADDR_LEN);
1154	dev->tx_queue_len = 16;
1155
1156	/* New style flags */
1157	dev->flags = 0;
1158}
1159
1160/* --------------------------------------------------------------------- */
1161
1162/*
1163 * command line settable parameters
1164 */
1165static char *mode[NR_PORTS] = { "", };
1166static int iobase[NR_PORTS] = { 0x378, };
1167
1168module_param_array(mode, charp, NULL, 0);
1169MODULE_PARM_DESC(mode, "baycom operating mode");
1170module_param_array(iobase, int, NULL, 0);
1171MODULE_PARM_DESC(iobase, "baycom io base address");
1172
1173MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
1174MODULE_DESCRIPTION("Baycom epp amateur radio modem driver");
1175MODULE_LICENSE("GPL");
1176
1177/* --------------------------------------------------------------------- */
1178
1179static void __init baycom_epp_dev_setup(struct net_device *dev)
1180{
1181	struct baycom_state *bc = netdev_priv(dev);
1182
1183	/*
1184	 * initialize part of the baycom_state struct
1185	 */
1186	bc->dev = dev;
1187	bc->magic = BAYCOM_MAGIC;
1188	bc->cfg.fclk = 19666600;
1189	bc->cfg.bps = 9600;
1190	/*
1191	 * initialize part of the device struct
1192	 */
1193	baycom_probe(dev);
1194}
1195
1196static int __init init_baycomepp(void)
1197{
1198	int i, found = 0;
1199	char set_hw = 1;
1200
1201	printk(bc_drvinfo);
1202	/*
1203	 * register net devices
1204	 */
1205	for (i = 0; i < NR_PORTS; i++) {
1206		struct net_device *dev;
1207
1208		dev = alloc_netdev(sizeof(struct baycom_state), "bce%d",
1209				   NET_NAME_UNKNOWN, baycom_epp_dev_setup);
1210
1211		if (!dev) {
1212			printk(KERN_WARNING "bce%d : out of memory\n", i);
1213			return found ? 0 : -ENOMEM;
1214		}
1215
1216		sprintf(dev->name, "bce%d", i);
1217		dev->base_addr = iobase[i];
1218
1219		if (!mode[i])
1220			set_hw = 0;
1221		if (!set_hw)
1222			iobase[i] = 0;
1223
1224		if (register_netdev(dev)) {
1225			printk(KERN_WARNING "%s: cannot register net device %s\n", bc_drvname, dev->name);
1226			free_netdev(dev);
1227			break;
1228		}
1229		if (set_hw && baycom_setmode(netdev_priv(dev), mode[i]))
1230			set_hw = 0;
1231		baycom_device[i] = dev;
1232		found++;
1233	}
1234
1235	return found ? 0 : -ENXIO;
1236}
1237
1238static void __exit cleanup_baycomepp(void)
1239{
1240	int i;
1241
1242	for(i = 0; i < NR_PORTS; i++) {
1243		struct net_device *dev = baycom_device[i];
1244
1245		if (dev) {
1246			struct baycom_state *bc = netdev_priv(dev);
1247			if (bc->magic == BAYCOM_MAGIC) {
1248				unregister_netdev(dev);
1249				free_netdev(dev);
1250			} else
1251				printk(paranoia_str, "cleanup_module");
1252		}
1253	}
1254}
1255
1256module_init(init_baycomepp);
1257module_exit(cleanup_baycomepp);
1258
1259/* --------------------------------------------------------------------- */
1260
1261#ifndef MODULE
1262
1263/*
1264 * format: baycom_epp=io,mode
1265 * mode: fpga config options
1266 */
1267
1268static int __init baycom_epp_setup(char *str)
1269{
1270        static unsigned __initdata nr_dev = 0;
1271	int ints[2];
1272
1273        if (nr_dev >= NR_PORTS)
1274                return 0;
1275	str = get_options(str, 2, ints);
1276	if (ints[0] < 1)
1277		return 0;
1278	mode[nr_dev] = str;
1279	iobase[nr_dev] = ints[1];
1280	nr_dev++;
1281	return 1;
1282}
1283
1284__setup("baycom_epp=", baycom_epp_setup);
1285
1286#endif /* MODULE */
1287/* --------------------------------------------------------------------- */
1288