xref: /freebsd/sys/dev/ppbus/if_plip.c (revision 4cf49a43559ed9fdad601bdcccd2c55963008675)
1 /*-
2  * Copyright (c) 1997 Poul-Henning Kamp
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  *	From Id: lpt.c,v 1.55.2.1 1996/11/12 09:08:38 phk Exp
27  * $FreeBSD$
28  */
29 
30 /*
31  * Parallel port TCP/IP interfaces added.  I looked at the driver from
32  * MACH but this is a complete rewrite, and btw. incompatible, and it
33  * should perform better too.  I have never run the MACH driver though.
34  *
35  * This driver sends two bytes (0x08, 0x00) in front of each packet,
36  * to allow us to distinguish another format later.
37  *
38  * Now added an Linux/Crynwr compatibility mode which is enabled using
39  * IF_LINK0 - Tim Wilkinson.
40  *
41  * TODO:
42  *    Make HDLC/PPP mode, use IF_LLC1 to enable.
43  *
44  * Connect the two computers using a Laplink parallel cable to use this
45  * feature:
46  *
47  *      +----------------------------------------+
48  * 	|A-name	A-End	B-End	Descr.	Port/Bit |
49  *      +----------------------------------------+
50  *	|DATA0	2	15	Data	0/0x01   |
51  *	|-ERROR	15	2	   	1/0x08   |
52  *      +----------------------------------------+
53  *	|DATA1	3	13	Data	0/0x02	 |
54  *	|+SLCT	13	3	   	1/0x10   |
55  *      +----------------------------------------+
56  *	|DATA2	4	12	Data	0/0x04   |
57  *	|+PE	12	4	   	1/0x20   |
58  *      +----------------------------------------+
59  *	|DATA3	5	10	Strobe	0/0x08   |
60  *	|-ACK	10	5	   	1/0x40   |
61  *      +----------------------------------------+
62  *	|DATA4	6	11	Data	0/0x10   |
63  *	|BUSY	11	6	   	1/~0x80  |
64  *      +----------------------------------------+
65  *	|GND	18-25	18-25	GND	-        |
66  *      +----------------------------------------+
67  *
68  * Expect transfer-rates up to 75 kbyte/sec.
69  *
70  * If GCC could correctly grok
71  *	register int port asm("edx")
72  * the code would be cleaner
73  *
74  * Poul-Henning Kamp <phk@freebsd.org>
75  */
76 
77 /*
78  * Update for ppbus, PLIP support only - Nicolas Souchu
79  */
80 
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/mbuf.h>
84 #include <sys/socket.h>
85 #include <sys/sockio.h>
86 #include <sys/kernel.h>
87 #include <sys/malloc.h>
88 
89 #include <net/if.h>
90 #include <net/if_types.h>
91 #include <net/netisr.h>
92 
93 #include <netinet/in.h>
94 #include <netinet/in_var.h>
95 
96 #include <net/bpf.h>
97 
98 #include <dev/ppbus/ppbconf.h>
99 
100 #include "opt_plip.h"
101 
102 #ifndef LPMTU			/* MTU for the lp# interfaces */
103 #define	LPMTU	1500
104 #endif
105 
106 #ifndef LPMAXSPIN1		/* DELAY factor for the lp# interfaces */
107 #define	LPMAXSPIN1	8000   /* Spinning for remote intr to happen */
108 #endif
109 
110 #ifndef LPMAXSPIN2		/* DELAY factor for the lp# interfaces */
111 #define	LPMAXSPIN2	500	/* Spinning for remote handshake to happen */
112 #endif
113 
114 #ifndef LPMAXERRS		/* Max errors before !RUNNING */
115 #define	LPMAXERRS	100
116 #endif
117 
118 #define CLPIPHDRLEN	14	/* We send dummy ethernet addresses (two) + packet type in front of packet */
119 #define	CLPIP_SHAKE	0x80	/* This bit toggles between nibble reception */
120 #define MLPIPHDRLEN	CLPIPHDRLEN
121 
122 #define LPIPHDRLEN	2	/* We send 0x08, 0x00 in front of packet */
123 #define	LPIP_SHAKE	0x40	/* This bit toggles between nibble reception */
124 #if !defined(MLPIPHDRLEN) || LPIPHDRLEN > MLPIPHDRLEN
125 #define MLPIPHDRLEN	LPIPHDRLEN
126 #endif
127 
128 #define	LPIPTBLSIZE	256	/* Size of octet translation table */
129 
130 #define lprintf		if (lptflag) printf
131 
132 #ifdef PLIP_DEBUG
133 static int volatile lptflag = 1;
134 #else
135 static int volatile lptflag = 0;
136 #endif
137 
138 struct lpt_softc {
139 	unsigned short lp_unit;
140 
141 	struct ppb_device lp_dev;
142 
143 	struct  ifnet	sc_if;
144 	u_char		*sc_ifbuf;
145 	int		sc_iferrs;
146 };
147 
148 static int	nlp = 0;
149 #define MAXPLIP	8			/* XXX not much better! */
150 static struct lpt_softc *lpdata[MAXPLIP];
151 
152 
153 /* Tables for the lp# interface */
154 static u_char *txmith;
155 #define txmitl (txmith+(1*LPIPTBLSIZE))
156 #define trecvh (txmith+(2*LPIPTBLSIZE))
157 #define trecvl (txmith+(3*LPIPTBLSIZE))
158 
159 static u_char *ctxmith;
160 #define ctxmitl (ctxmith+(1*LPIPTBLSIZE))
161 #define ctrecvh (ctxmith+(2*LPIPTBLSIZE))
162 #define ctrecvl (ctxmith+(3*LPIPTBLSIZE))
163 
164 /* Functions for the lp# interface */
165 static struct ppb_device	*lpprobe(struct ppb_data *);
166 static int			lpattach(struct ppb_device *);
167 
168 static int lpinittables(void);
169 static int lpioctl(struct ifnet *, u_long, caddr_t);
170 static int lpoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
171 	struct rtentry *);
172 static void lpintr(int);
173 
174 /*
175  * Make ourselves visible as a ppbus driver
176  */
177 
178 static struct ppb_driver lpdriver = {
179     lpprobe, lpattach, "lp"
180 };
181 DATA_SET(ppbdriver_set, lpdriver);
182 
183 
184 /*
185  * lpprobe()
186  */
187 static struct ppb_device *
188 lpprobe(struct ppb_data *ppb)
189 {
190 	struct lpt_softc *lp;
191 
192 	/* if we haven't interrupts, the probe fails */
193 	if (!ppb->ppb_link->id_irq) {
194 		printf("plip: not an interrupt driven port, failed.\n");
195 		return (0);
196 	}
197 
198 	lp = (struct lpt_softc *) malloc(sizeof(struct lpt_softc),
199 							M_TEMP, M_NOWAIT);
200 	if (!lp) {
201 		printf("lp: cannot malloc!\n");
202 		return (0);
203 	}
204 	bzero(lp, sizeof(struct lpt_softc));
205 
206 	lpdata[nlp] = lp;
207 
208 	/*
209 	 * lp dependent initialisation.
210 	 */
211 	lp->lp_unit = nlp;
212 
213 	if (bootverbose)
214 		printf("plip: irq %d\n", ppb->ppb_link->id_irq);
215 
216 	/*
217 	 * ppbus dependent initialisation.
218 	 */
219 	lp->lp_dev.id_unit = lp->lp_unit;
220 	lp->lp_dev.name = lpdriver.name;
221 	lp->lp_dev.ppb = ppb;
222 	lp->lp_dev.intr = lpintr;
223 
224 	/* Ok, go to next device on next probe */
225 	nlp ++;
226 
227 	return (&lp->lp_dev);
228 }
229 
230 static int
231 lpattach (struct ppb_device *dev)
232 {
233 	int unit = dev->id_unit;
234 	struct lpt_softc *sc = lpdata[unit];
235 	struct ifnet *ifp = &sc->sc_if;
236 
237 	/*
238 	 * Report ourselves
239 	 */
240 	printf("plip%d: <PLIP network interface> on ppbus %d\n",
241 	       dev->id_unit, dev->ppb->ppb_link->adapter_unit);
242 
243 	ifp->if_softc = sc;
244 	ifp->if_name = "lp";
245 	ifp->if_unit = unit;
246 	ifp->if_mtu = LPMTU;
247 	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
248 	ifp->if_ioctl = lpioctl;
249 	ifp->if_output = lpoutput;
250 	ifp->if_type = IFT_PARA;
251 	ifp->if_hdrlen = 0;
252 	ifp->if_addrlen = 0;
253 	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
254 	if_attach(ifp);
255 
256 	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
257 
258 	return (1);
259 }
260 /*
261  * Build the translation tables for the LPIP (BSD unix) protocol.
262  * We don't want to calculate these nasties in our tight loop, so we
263  * precalculate them when we initialize.
264  */
265 static int
266 lpinittables (void)
267 {
268     int i;
269 
270     if (!txmith)
271 	txmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
272 
273     if (!txmith)
274 	return 1;
275 
276     if (!ctxmith)
277 	ctxmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
278 
279     if (!ctxmith)
280 	return 1;
281 
282     for (i=0; i < LPIPTBLSIZE; i++) {
283 	ctxmith[i] = (i & 0xF0) >> 4;
284 	ctxmitl[i] = 0x10 | (i & 0x0F);
285 	ctrecvh[i] = (i & 0x78) << 1;
286 	ctrecvl[i] = (i & 0x78) >> 3;
287     }
288 
289     for (i=0; i < LPIPTBLSIZE; i++) {
290 	txmith[i] = ((i & 0x80) >> 3) | ((i & 0x70) >> 4) | 0x08;
291 	txmitl[i] = ((i & 0x08) << 1) | (i & 0x07);
292 	trecvh[i] = ((~i) & 0x80) | ((i & 0x38) << 1);
293 	trecvl[i] = (((~i) & 0x80) >> 4) | ((i & 0x38) >> 3);
294     }
295 
296     return 0;
297 }
298 
299 /*
300  * Process an ioctl request.
301  */
302 
303 static int
304 lpioctl (struct ifnet *ifp, u_long cmd, caddr_t data)
305 {
306     struct lpt_softc *sc = lpdata[ifp->if_unit];
307     struct ifaddr *ifa = (struct ifaddr *)data;
308     struct ifreq *ifr = (struct ifreq *)data;
309     u_char *ptr;
310     int error;
311 
312     switch (cmd) {
313 
314     case SIOCSIFDSTADDR:
315     case SIOCAIFADDR:
316     case SIOCSIFADDR:
317 	if (ifa->ifa_addr->sa_family != AF_INET)
318 	    return EAFNOSUPPORT;
319 
320 	ifp->if_flags |= IFF_UP;
321 	/* FALLTHROUGH */
322     case SIOCSIFFLAGS:
323 	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
324 
325 	    ppb_wctr(&sc->lp_dev, 0x00);
326 	    ifp->if_flags &= ~IFF_RUNNING;
327 
328 	    /* IFF_UP is not set, try to release the bus anyway */
329 	    ppb_release_bus(&sc->lp_dev);
330 	    break;
331 	}
332 	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
333 
334 	    /* XXX
335 	     * Should the request be interruptible?
336 	     */
337 	    if ((error = ppb_request_bus(&sc->lp_dev, PPB_WAIT|PPB_INTR)))
338 		return (error);
339 
340 	    /* Now IFF_UP means that we own the bus */
341 
342 	    ppb_set_mode(&sc->lp_dev, PPB_COMPATIBLE);
343 
344 	    if (lpinittables()) {
345 		ppb_release_bus(&sc->lp_dev);
346 		return ENOBUFS;
347 	    }
348 
349 	    sc->sc_ifbuf = malloc(sc->sc_if.if_mtu + MLPIPHDRLEN,
350 				  M_DEVBUF, M_WAITOK);
351 	    if (!sc->sc_ifbuf) {
352 		ppb_release_bus(&sc->lp_dev);
353 		return ENOBUFS;
354 	    }
355 
356 	    ppb_wctr(&sc->lp_dev, IRQENABLE);
357 	    ifp->if_flags |= IFF_RUNNING;
358 	}
359 	break;
360 
361     case SIOCSIFMTU:
362 	ptr = sc->sc_ifbuf;
363 	sc->sc_ifbuf = malloc(ifr->ifr_mtu+MLPIPHDRLEN, M_DEVBUF, M_NOWAIT);
364 	if (!sc->sc_ifbuf) {
365 	    sc->sc_ifbuf = ptr;
366 	    return ENOBUFS;
367 	}
368 	if (ptr)
369 	    free(ptr,M_DEVBUF);
370 	sc->sc_if.if_mtu = ifr->ifr_mtu;
371 	break;
372 
373     case SIOCGIFMTU:
374 	ifr->ifr_mtu = sc->sc_if.if_mtu;
375 	break;
376 
377     case SIOCADDMULTI:
378     case SIOCDELMULTI:
379 	if (ifr == 0) {
380 	    return EAFNOSUPPORT;		/* XXX */
381 	}
382 	switch (ifr->ifr_addr.sa_family) {
383 
384 	case AF_INET:
385 	    break;
386 
387 	default:
388 	    return EAFNOSUPPORT;
389 	}
390 	break;
391 
392     case SIOCGIFMEDIA:
393 	/*
394 	 * No ifmedia support at this stage; maybe use it
395 	 * in future for eg. protocol selection.
396 	 */
397 	return EINVAL;
398 
399     default:
400 	lprintf("LP:ioctl(0x%lx)\n", cmd);
401 	return EINVAL;
402     }
403     return 0;
404 }
405 
406 static __inline int
407 clpoutbyte (u_char byte, int spin, struct ppb_device *dev)
408 {
409 	ppb_wdtr(dev, ctxmitl[byte]);
410 	while (ppb_rstr(dev) & CLPIP_SHAKE)
411 		if (--spin == 0) {
412 			return 1;
413 		}
414 	ppb_wdtr(dev, ctxmith[byte]);
415 	while (!(ppb_rstr(dev) & CLPIP_SHAKE))
416 		if (--spin == 0) {
417 			return 1;
418 		}
419 	return 0;
420 }
421 
422 static __inline int
423 clpinbyte (int spin, struct ppb_device *dev)
424 {
425 	u_char c, cl;
426 
427 	while((ppb_rstr(dev) & CLPIP_SHAKE))
428 	    if(!--spin) {
429 		return -1;
430 	    }
431 	cl = ppb_rstr(dev);
432 	ppb_wdtr(dev, 0x10);
433 
434 	while(!(ppb_rstr(dev) & CLPIP_SHAKE))
435 	    if(!--spin) {
436 		return -1;
437 	    }
438 	c = ppb_rstr(dev);
439 	ppb_wdtr(dev, 0x00);
440 
441 	return (ctrecvl[cl] | ctrecvh[c]);
442 }
443 
444 static void
445 lptap(struct ifnet *ifp, struct mbuf *m)
446 {
447 	/*
448 	 * Send a packet through bpf. We need to prepend the address family
449 	 * as a four byte field. Cons up a dummy header to pacify bpf. This
450 	 * is safe because bpf will only read from the mbuf (i.e., it won't
451 	 * try to free it or keep a pointer to it).
452 	 */
453 	u_int32_t af = AF_INET;
454 	struct mbuf m0;
455 
456 	m0.m_next = m;
457 	m0.m_len = sizeof(u_int32_t);
458 	m0.m_data = (char *)&af;
459 	bpf_mtap(ifp, &m0);
460 }
461 
462 static void
463 lpintr (int unit)
464 {
465 	struct   lpt_softc *sc = lpdata[unit];
466 	int len, s, j;
467 	u_char *bp;
468 	u_char c, cl;
469 	struct mbuf *top;
470 
471 	s = splhigh();
472 
473 	if (sc->sc_if.if_flags & IFF_LINK0) {
474 
475 	    /* Ack. the request */
476 	    ppb_wdtr(&sc->lp_dev, 0x01);
477 
478 	    /* Get the packet length */
479 	    j = clpinbyte(LPMAXSPIN2, &sc->lp_dev);
480 	    if (j == -1)
481 		goto err;
482 	    len = j;
483 	    j = clpinbyte(LPMAXSPIN2, &sc->lp_dev);
484 	    if (j == -1)
485 		goto err;
486 	    len = len + (j << 8);
487 	    if (len > sc->sc_if.if_mtu + MLPIPHDRLEN)
488 		goto err;
489 
490 	    bp  = sc->sc_ifbuf;
491 
492 	    while (len--) {
493 	        j = clpinbyte(LPMAXSPIN2, &sc->lp_dev);
494 	        if (j == -1) {
495 		    goto err;
496 	        }
497 	        *bp++ = j;
498 	    }
499 	    /* Get and ignore checksum */
500 	    j = clpinbyte(LPMAXSPIN2, &sc->lp_dev);
501 	    if (j == -1) {
502 	        goto err;
503 	    }
504 
505 	    len = bp - sc->sc_ifbuf;
506 	    if (len <= CLPIPHDRLEN)
507 	        goto err;
508 
509 	    sc->sc_iferrs = 0;
510 
511 	    if (IF_QFULL(&ipintrq)) {
512 	        lprintf("DROP");
513 	        IF_DROP(&ipintrq);
514 		goto done;
515 	    }
516 	    len -= CLPIPHDRLEN;
517 	    sc->sc_if.if_ipackets++;
518 	    sc->sc_if.if_ibytes += len;
519 	    top = m_devget(sc->sc_ifbuf + CLPIPHDRLEN, len, 0, &sc->sc_if, 0);
520 	    if (top) {
521 		if (sc->sc_if.if_bpf)
522 		    lptap(&sc->sc_if, top);
523 	        IF_ENQUEUE(&ipintrq, top);
524 	        schednetisr(NETISR_IP);
525 	    }
526 	    goto done;
527 	}
528 	while ((ppb_rstr(&sc->lp_dev) & LPIP_SHAKE)) {
529 	    len = sc->sc_if.if_mtu + LPIPHDRLEN;
530 	    bp  = sc->sc_ifbuf;
531 	    while (len--) {
532 
533 		cl = ppb_rstr(&sc->lp_dev);
534 		ppb_wdtr(&sc->lp_dev, 8);
535 
536 		j = LPMAXSPIN2;
537 		while((ppb_rstr(&sc->lp_dev) & LPIP_SHAKE))
538 		    if(!--j) goto err;
539 
540 		c = ppb_rstr(&sc->lp_dev);
541 		ppb_wdtr(&sc->lp_dev, 0);
542 
543 		*bp++= trecvh[cl] | trecvl[c];
544 
545 		j = LPMAXSPIN2;
546 		while (!((cl=ppb_rstr(&sc->lp_dev)) & LPIP_SHAKE)) {
547 		    if (cl != c &&
548 			(((cl = ppb_rstr(&sc->lp_dev)) ^ 0xb8) & 0xf8) ==
549 			  (c & 0xf8))
550 			goto end;
551 		    if (!--j) goto err;
552 		}
553 	    }
554 
555 	end:
556 	    len = bp - sc->sc_ifbuf;
557 	    if (len <= LPIPHDRLEN)
558 		goto err;
559 
560 	    sc->sc_iferrs = 0;
561 
562 	    if (IF_QFULL(&ipintrq)) {
563 		lprintf("DROP");
564 		IF_DROP(&ipintrq);
565 		goto done;
566 	    }
567 	    len -= LPIPHDRLEN;
568 	    sc->sc_if.if_ipackets++;
569 	    sc->sc_if.if_ibytes += len;
570 	    top = m_devget(sc->sc_ifbuf + LPIPHDRLEN, len, 0, &sc->sc_if, 0);
571 	    if (top) {
572 		if (sc->sc_if.if_bpf)
573 		    lptap(&sc->sc_if, top);
574 		IF_ENQUEUE(&ipintrq, top);
575 		schednetisr(NETISR_IP);
576 	    }
577 	}
578 	goto done;
579 
580     err:
581 	ppb_wdtr(&sc->lp_dev, 0);
582 	lprintf("R");
583 	sc->sc_if.if_ierrors++;
584 	sc->sc_iferrs++;
585 
586 	/*
587 	 * We are not able to send receive anything for now,
588 	 * so stop wasting our time
589 	 */
590 	if (sc->sc_iferrs > LPMAXERRS) {
591 	    printf("lp%d: Too many errors, Going off-line.\n", unit);
592 	    ppb_wctr(&sc->lp_dev, 0x00);
593 	    sc->sc_if.if_flags &= ~IFF_RUNNING;
594 	    sc->sc_iferrs=0;
595 	}
596 
597     done:
598 	splx(s);
599 	return;
600 }
601 
602 static __inline int
603 lpoutbyte (u_char byte, int spin, struct ppb_device *dev)
604 {
605     ppb_wdtr(dev, txmith[byte]);
606     while (!(ppb_rstr(dev) & LPIP_SHAKE))
607 	if (--spin == 0)
608 		return 1;
609     ppb_wdtr(dev, txmitl[byte]);
610     while (ppb_rstr(dev) & LPIP_SHAKE)
611 	if (--spin == 0)
612 		return 1;
613     return 0;
614 }
615 
616 static int
617 lpoutput (struct ifnet *ifp, struct mbuf *m,
618 	  struct sockaddr *dst, struct rtentry *rt)
619 {
620     struct lpt_softc *sc = lpdata[ifp->if_unit];
621     int s, err;
622     struct mbuf *mm;
623     u_char *cp = "\0\0";
624     u_char chksum = 0;
625     int count = 0;
626     int i, len, spin;
627 
628     /* We need a sensible value if we abort */
629     cp++;
630     ifp->if_flags |= IFF_RUNNING;
631 
632     err = 1;			/* assume we're aborting because of an error */
633 
634     s = splhigh();
635 
636     /* Suspend (on laptops) or receive-errors might have taken us offline */
637     ppb_wctr(&sc->lp_dev, IRQENABLE);
638 
639     if (ifp->if_flags & IFF_LINK0) {
640 
641 	if (!(ppb_rstr(&sc->lp_dev) & CLPIP_SHAKE)) {
642 	    lprintf("&");
643 	    lpintr(ifp->if_unit);
644 	}
645 
646 	/* Alert other end to pending packet */
647 	spin = LPMAXSPIN1;
648 	ppb_wdtr(&sc->lp_dev, 0x08);
649 	while ((ppb_rstr(&sc->lp_dev) & 0x08) == 0)
650 		if (--spin == 0) {
651 			goto nend;
652 		}
653 
654 	/* Calculate length of packet, then send that */
655 
656 	count += 14;		/* Ethernet header len */
657 
658 	mm = m;
659 	for (mm = m; mm; mm = mm->m_next) {
660 		count += mm->m_len;
661 	}
662 	if (clpoutbyte(count & 0xFF, LPMAXSPIN1, &sc->lp_dev))
663 		goto nend;
664 	if (clpoutbyte((count >> 8) & 0xFF, LPMAXSPIN1, &sc->lp_dev))
665 		goto nend;
666 
667 	/* Send dummy ethernet header */
668 	for (i = 0; i < 12; i++) {
669 		if (clpoutbyte(i, LPMAXSPIN1, &sc->lp_dev))
670 			goto nend;
671 		chksum += i;
672 	}
673 
674 	if (clpoutbyte(0x08, LPMAXSPIN1, &sc->lp_dev))
675 		goto nend;
676 	if (clpoutbyte(0x00, LPMAXSPIN1, &sc->lp_dev))
677 		goto nend;
678 	chksum += 0x08 + 0x00;		/* Add into checksum */
679 
680 	mm = m;
681 	do {
682 		cp = mtod(mm, u_char *);
683 		len = mm->m_len;
684 		while (len--) {
685 			chksum += *cp;
686 			if (clpoutbyte(*cp++, LPMAXSPIN2, &sc->lp_dev))
687 				goto nend;
688 		}
689 	} while ((mm = mm->m_next));
690 
691 	/* Send checksum */
692 	if (clpoutbyte(chksum, LPMAXSPIN2, &sc->lp_dev))
693 		goto nend;
694 
695 	/* Go quiescent */
696 	ppb_wdtr(&sc->lp_dev, 0);
697 
698 	err = 0;			/* No errors */
699 
700 	nend:
701 	if (err)  {				/* if we didn't timeout... */
702 		ifp->if_oerrors++;
703 		lprintf("X");
704 	} else {
705 		ifp->if_opackets++;
706 		ifp->if_obytes += m->m_pkthdr.len;
707 		if (ifp->if_bpf)
708 		    lptap(ifp, m);
709 	}
710 
711 	m_freem(m);
712 
713 	if (!(ppb_rstr(&sc->lp_dev) & CLPIP_SHAKE)) {
714 		lprintf("^");
715 		lpintr(ifp->if_unit);
716 	}
717 	(void) splx(s);
718 	return 0;
719     }
720 
721     if (ppb_rstr(&sc->lp_dev) & LPIP_SHAKE) {
722         lprintf("&");
723         lpintr(ifp->if_unit);
724     }
725 
726     if (lpoutbyte(0x08, LPMAXSPIN1, &sc->lp_dev))
727         goto end;
728     if (lpoutbyte(0x00, LPMAXSPIN2, &sc->lp_dev))
729         goto end;
730 
731     mm = m;
732     do {
733         cp = mtod(mm,u_char *);
734 	len = mm->m_len;
735         while (len--)
736 	    if (lpoutbyte(*cp++, LPMAXSPIN2, &sc->lp_dev))
737 	        goto end;
738     } while ((mm = mm->m_next));
739 
740     err = 0;				/* no errors were encountered */
741 
742     end:
743     --cp;
744     ppb_wdtr(&sc->lp_dev, txmitl[*cp] ^ 0x17);
745 
746     if (err)  {				/* if we didn't timeout... */
747 	ifp->if_oerrors++;
748         lprintf("X");
749     } else {
750 	ifp->if_opackets++;
751 	ifp->if_obytes += m->m_pkthdr.len;
752 	if (ifp->if_bpf)
753 	    lptap(ifp, m);
754     }
755 
756     m_freem(m);
757 
758     if (ppb_rstr(&sc->lp_dev) & LPIP_SHAKE) {
759 	lprintf("^");
760 	lpintr(ifp->if_unit);
761     }
762 
763     (void) splx(s);
764     return 0;
765 }
766