if_plip.c revision 94154 
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: head/sys/dev/ppbus/if_plip.c 94154 2002-04-07 22:06:20Z ticso $
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 "opt_plip.h"
82
83#include <sys/param.h>
84#include <sys/systm.h>
85#include <sys/module.h>
86#include <sys/bus.h>
87#include <sys/mbuf.h>
88#include <sys/socket.h>
89#include <sys/sockio.h>
90#include <sys/kernel.h>
91#include <sys/malloc.h>
92
93#include <machine/bus.h>
94#include <machine/resource.h>
95#include <sys/rman.h>
96
97#include <net/if.h>
98#include <net/if_types.h>
99#include <net/netisr.h>
100
101#include <netinet/in.h>
102#include <netinet/in_var.h>
103
104#include <net/bpf.h>
105
106#include <dev/ppbus/ppbconf.h>
107#include "ppbus_if.h"
108#include <dev/ppbus/ppbio.h>
109
110#ifndef LPMTU			/* MTU for the lp# interfaces */
111#define	LPMTU	1500
112#endif
113
114#ifndef LPMAXSPIN1		/* DELAY factor for the lp# interfaces */
115#define	LPMAXSPIN1	8000   /* Spinning for remote intr to happen */
116#endif
117
118#ifndef LPMAXSPIN2		/* DELAY factor for the lp# interfaces */
119#define	LPMAXSPIN2	500	/* Spinning for remote handshake to happen */
120#endif
121
122#ifndef LPMAXERRS		/* Max errors before !RUNNING */
123#define	LPMAXERRS	100
124#endif
125
126#define CLPIPHDRLEN	14	/* We send dummy ethernet addresses (two) + packet type in front of packet */
127#define	CLPIP_SHAKE	0x80	/* This bit toggles between nibble reception */
128#define MLPIPHDRLEN	CLPIPHDRLEN
129
130#define LPIPHDRLEN	2	/* We send 0x08, 0x00 in front of packet */
131#define	LPIP_SHAKE	0x40	/* This bit toggles between nibble reception */
132#if !defined(MLPIPHDRLEN) || LPIPHDRLEN > MLPIPHDRLEN
133#define MLPIPHDRLEN	LPIPHDRLEN
134#endif
135
136#define	LPIPTBLSIZE	256	/* Size of octet translation table */
137
138#define lprintf		if (lptflag) printf
139
140#ifdef PLIP_DEBUG
141static int volatile lptflag = 1;
142#else
143static int volatile lptflag = 0;
144#endif
145
146struct lp_data {
147	unsigned short lp_unit;
148
149	struct  ifnet	sc_if;
150	u_char		*sc_ifbuf;
151	int		sc_iferrs;
152
153	struct resource *res_irq;
154};
155
156/* Tables for the lp# interface */
157static u_char *txmith;
158#define txmitl (txmith+(1*LPIPTBLSIZE))
159#define trecvh (txmith+(2*LPIPTBLSIZE))
160#define trecvl (txmith+(3*LPIPTBLSIZE))
161
162static u_char *ctxmith;
163#define ctxmitl (ctxmith+(1*LPIPTBLSIZE))
164#define ctrecvh (ctxmith+(2*LPIPTBLSIZE))
165#define ctrecvl (ctxmith+(3*LPIPTBLSIZE))
166
167/* Functions for the lp# interface */
168static int lpinittables(void);
169static int lpioctl(struct ifnet *, u_long, caddr_t);
170static int lpoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
171	struct rtentry *);
172static void lp_intr(void *);
173
174#define DEVTOSOFTC(dev) \
175	((struct lp_data *)device_get_softc(dev))
176#define UNITOSOFTC(unit) \
177	((struct lp_data *)devclass_get_softc(lp_devclass, (unit)))
178#define UNITODEVICE(unit) \
179	(devclass_get_device(lp_devclass, (unit)))
180
181static devclass_t lp_devclass;
182
183static void
184lp_identify(driver_t *driver, device_t parent)
185{
186
187	BUS_ADD_CHILD(parent, 0, "plip", -1);
188}
189/*
190 * lpprobe()
191 */
192static int
193lp_probe(device_t dev)
194{
195	device_t ppbus = device_get_parent(dev);
196	struct lp_data *lp;
197	int zero = 0;
198	uintptr_t irq;
199
200	lp = DEVTOSOFTC(dev);
201	bzero(lp, sizeof(struct lp_data));
202
203	/* retrieve the ppbus irq */
204	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
205
206	/* if we haven't interrupts, the probe fails */
207	if (irq == -1) {
208		device_printf(dev, "not an interrupt driven port, failed.\n");
209		return (ENXIO);
210	}
211
212	/* reserve the interrupt resource, expecting irq is available to continue */
213	lp->res_irq = bus_alloc_resource(dev, SYS_RES_IRQ, &zero, irq, irq, 1,
214					 RF_SHAREABLE);
215	if (lp->res_irq == 0) {
216		device_printf(dev, "cannot reserve interrupt, failed.\n");
217		return (ENXIO);
218	}
219
220	/*
221	 * lp dependent initialisation.
222	 */
223	lp->lp_unit = device_get_unit(dev);
224
225	device_set_desc(dev, "PLIP network interface");
226
227	return (0);
228}
229
230static int
231lp_attach (device_t dev)
232{
233	struct lp_data *lp = DEVTOSOFTC(dev);
234	struct ifnet *ifp = &lp->sc_if;
235
236	ifp->if_softc = lp;
237	ifp->if_name = "lp";
238	ifp->if_unit = device_get_unit(dev);
239	ifp->if_mtu = LPMTU;
240	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
241	ifp->if_ioctl = lpioctl;
242	ifp->if_output = lpoutput;
243	ifp->if_type = IFT_PARA;
244	ifp->if_hdrlen = 0;
245	ifp->if_addrlen = 0;
246	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
247	if_attach(ifp);
248
249	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
250
251	return (0);
252}
253/*
254 * Build the translation tables for the LPIP (BSD unix) protocol.
255 * We don't want to calculate these nasties in our tight loop, so we
256 * precalculate them when we initialize.
257 */
258static int
259lpinittables (void)
260{
261    int i;
262
263    if (!txmith)
264	txmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
265
266    if (!txmith)
267	return 1;
268
269    if (!ctxmith)
270	ctxmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
271
272    if (!ctxmith)
273	return 1;
274
275    for (i=0; i < LPIPTBLSIZE; i++) {
276	ctxmith[i] = (i & 0xF0) >> 4;
277	ctxmitl[i] = 0x10 | (i & 0x0F);
278	ctrecvh[i] = (i & 0x78) << 1;
279	ctrecvl[i] = (i & 0x78) >> 3;
280    }
281
282    for (i=0; i < LPIPTBLSIZE; i++) {
283	txmith[i] = ((i & 0x80) >> 3) | ((i & 0x70) >> 4) | 0x08;
284	txmitl[i] = ((i & 0x08) << 1) | (i & 0x07);
285	trecvh[i] = ((~i) & 0x80) | ((i & 0x38) << 1);
286	trecvl[i] = (((~i) & 0x80) >> 4) | ((i & 0x38) >> 3);
287    }
288
289    return 0;
290}
291
292/*
293 * Process an ioctl request.
294 */
295
296static int
297lpioctl (struct ifnet *ifp, u_long cmd, caddr_t data)
298{
299    device_t dev = UNITODEVICE(ifp->if_unit);
300    device_t ppbus = device_get_parent(dev);
301    struct lp_data *sc = DEVTOSOFTC(dev);
302    struct ifaddr *ifa = (struct ifaddr *)data;
303    struct ifreq *ifr = (struct ifreq *)data;
304    u_char *ptr;
305    void *ih;
306    int error;
307
308    switch (cmd) {
309
310    case SIOCSIFDSTADDR:
311    case SIOCAIFADDR:
312    case SIOCSIFADDR:
313	if (ifa->ifa_addr->sa_family != AF_INET)
314	    return EAFNOSUPPORT;
315
316	ifp->if_flags |= IFF_UP;
317	/* FALLTHROUGH */
318    case SIOCSIFFLAGS:
319	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
320
321	    ppb_wctr(ppbus, 0x00);
322	    ifp->if_flags &= ~IFF_RUNNING;
323
324	    /* IFF_UP is not set, try to release the bus anyway */
325	    ppb_release_bus(ppbus, dev);
326	    break;
327	}
328	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
329
330	    /* XXX
331	     * Should the request be interruptible?
332	     */
333	    if ((error = ppb_request_bus(ppbus, dev, PPB_WAIT|PPB_INTR)))
334		return (error);
335
336	    /* Now IFF_UP means that we own the bus */
337
338	    ppb_set_mode(ppbus, PPB_COMPATIBLE);
339
340	    if (lpinittables()) {
341		ppb_release_bus(ppbus, dev);
342		return ENOBUFS;
343	    }
344
345	    sc->sc_ifbuf = malloc(sc->sc_if.if_mtu + MLPIPHDRLEN,
346				  M_DEVBUF, M_WAITOK);
347	    if (!sc->sc_ifbuf) {
348		ppb_release_bus(ppbus, dev);
349		return ENOBUFS;
350	    }
351
352	    /* attach our interrupt handler, later detached when the bus is released */
353	    if ((error = BUS_SETUP_INTR(ppbus, dev, sc->res_irq,
354					INTR_TYPE_NET, lp_intr, dev, &ih))) {
355		ppb_release_bus(ppbus, dev);
356		return (error);
357	    }
358
359	    ppb_wctr(ppbus, IRQENABLE);
360	    ifp->if_flags |= IFF_RUNNING;
361	}
362	break;
363
364    case SIOCSIFMTU:
365	ptr = sc->sc_ifbuf;
366	sc->sc_ifbuf = malloc(ifr->ifr_mtu+MLPIPHDRLEN, M_DEVBUF, M_NOWAIT);
367	if (!sc->sc_ifbuf) {
368	    sc->sc_ifbuf = ptr;
369	    return ENOBUFS;
370	}
371	if (ptr)
372	    free(ptr,M_DEVBUF);
373	sc->sc_if.if_mtu = ifr->ifr_mtu;
374	break;
375
376    case SIOCGIFMTU:
377	ifr->ifr_mtu = sc->sc_if.if_mtu;
378	break;
379
380    case SIOCADDMULTI:
381    case SIOCDELMULTI:
382	if (ifr == 0) {
383	    return EAFNOSUPPORT;		/* XXX */
384	}
385	switch (ifr->ifr_addr.sa_family) {
386
387	case AF_INET:
388	    break;
389
390	default:
391	    return EAFNOSUPPORT;
392	}
393	break;
394
395    case SIOCGIFMEDIA:
396	/*
397	 * No ifmedia support at this stage; maybe use it
398	 * in future for eg. protocol selection.
399	 */
400	return EINVAL;
401
402    default:
403	lprintf("LP:ioctl(0x%lx)\n", cmd);
404	return EINVAL;
405    }
406    return 0;
407}
408
409static __inline int
410clpoutbyte (u_char byte, int spin, device_t ppbus)
411{
412	ppb_wdtr(ppbus, ctxmitl[byte]);
413	while (ppb_rstr(ppbus) & CLPIP_SHAKE)
414		if (--spin == 0) {
415			return 1;
416		}
417	ppb_wdtr(ppbus, ctxmith[byte]);
418	while (!(ppb_rstr(ppbus) & CLPIP_SHAKE))
419		if (--spin == 0) {
420			return 1;
421		}
422	return 0;
423}
424
425static __inline int
426clpinbyte (int spin, device_t ppbus)
427{
428	u_char c, cl;
429
430	while((ppb_rstr(ppbus) & CLPIP_SHAKE))
431	    if(!--spin) {
432		return -1;
433	    }
434	cl = ppb_rstr(ppbus);
435	ppb_wdtr(ppbus, 0x10);
436
437	while(!(ppb_rstr(ppbus) & CLPIP_SHAKE))
438	    if(!--spin) {
439		return -1;
440	    }
441	c = ppb_rstr(ppbus);
442	ppb_wdtr(ppbus, 0x00);
443
444	return (ctrecvl[cl] | ctrecvh[c]);
445}
446
447static void
448lptap(struct ifnet *ifp, struct mbuf *m)
449{
450	/*
451	 * Send a packet through bpf. We need to prepend the address family
452	 * as a four byte field. Cons up a dummy header to pacify bpf. This
453	 * is safe because bpf will only read from the mbuf (i.e., it won't
454	 * try to free it or keep a pointer to it).
455	 */
456	u_int32_t af = AF_INET;
457	struct mbuf m0;
458
459	m0.m_next = m;
460	m0.m_len = sizeof(u_int32_t);
461	m0.m_data = (char *)&af;
462	bpf_mtap(ifp, &m0);
463}
464
465static void
466lp_intr (void *arg)
467{
468	device_t dev = (device_t)arg;
469        device_t ppbus = device_get_parent(dev);
470	struct lp_data *sc = DEVTOSOFTC(dev);
471	int len, s, j;
472	u_char *bp;
473	u_char c, cl;
474	struct mbuf *top;
475
476	s = splhigh();
477
478	if (sc->sc_if.if_flags & IFF_LINK0) {
479
480	    /* Ack. the request */
481	    ppb_wdtr(ppbus, 0x01);
482
483	    /* Get the packet length */
484	    j = clpinbyte(LPMAXSPIN2, ppbus);
485	    if (j == -1)
486		goto err;
487	    len = j;
488	    j = clpinbyte(LPMAXSPIN2, ppbus);
489	    if (j == -1)
490		goto err;
491	    len = len + (j << 8);
492	    if (len > sc->sc_if.if_mtu + MLPIPHDRLEN)
493		goto err;
494
495	    bp  = sc->sc_ifbuf;
496
497	    while (len--) {
498	        j = clpinbyte(LPMAXSPIN2, ppbus);
499	        if (j == -1) {
500		    goto err;
501	        }
502	        *bp++ = j;
503	    }
504	    /* Get and ignore checksum */
505	    j = clpinbyte(LPMAXSPIN2, ppbus);
506	    if (j == -1) {
507	        goto err;
508	    }
509
510	    len = bp - sc->sc_ifbuf;
511	    if (len <= CLPIPHDRLEN)
512	        goto err;
513
514	    sc->sc_iferrs = 0;
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 (! IF_HANDOFF(&ipintrq, top, NULL)) {
524	            lprintf("DROP");
525                } else {
526	            schednetisr(NETISR_IP);
527	        }
528	    }
529	    goto done;
530	}
531	while ((ppb_rstr(ppbus) & LPIP_SHAKE)) {
532	    len = sc->sc_if.if_mtu + LPIPHDRLEN;
533	    bp  = sc->sc_ifbuf;
534	    while (len--) {
535
536		cl = ppb_rstr(ppbus);
537		ppb_wdtr(ppbus, 8);
538
539		j = LPMAXSPIN2;
540		while((ppb_rstr(ppbus) & LPIP_SHAKE))
541		    if(!--j) goto err;
542
543		c = ppb_rstr(ppbus);
544		ppb_wdtr(ppbus, 0);
545
546		*bp++= trecvh[cl] | trecvl[c];
547
548		j = LPMAXSPIN2;
549		while (!((cl=ppb_rstr(ppbus)) & LPIP_SHAKE)) {
550		    if (cl != c &&
551			(((cl = ppb_rstr(ppbus)) ^ 0xb8) & 0xf8) ==
552			  (c & 0xf8))
553			goto end;
554		    if (!--j) goto err;
555		}
556	    }
557
558	end:
559	    len = bp - sc->sc_ifbuf;
560	    if (len <= LPIPHDRLEN)
561		goto err;
562
563	    sc->sc_iferrs = 0;
564
565	    len -= LPIPHDRLEN;
566	    sc->sc_if.if_ipackets++;
567	    sc->sc_if.if_ibytes += len;
568	    top = m_devget(sc->sc_ifbuf + LPIPHDRLEN, len, 0, &sc->sc_if, 0);
569	    if (top) {
570		if (sc->sc_if.if_bpf)
571		    lptap(&sc->sc_if, top);
572                if (! IF_HANDOFF(&ipintrq, top, NULL))  {
573		    lprintf("DROP");
574                } else {
575		    schednetisr(NETISR_IP);
576	        }
577	    }
578	}
579	goto done;
580
581    err:
582	ppb_wdtr(ppbus, 0);
583	lprintf("R");
584	sc->sc_if.if_ierrors++;
585	sc->sc_iferrs++;
586
587	/*
588	 * We are not able to send receive anything for now,
589	 * so stop wasting our time
590	 */
591	if (sc->sc_iferrs > LPMAXERRS) {
592	    printf("lp%d: Too many errors, Going off-line.\n", device_get_unit(dev));
593	    ppb_wctr(ppbus, 0x00);
594	    sc->sc_if.if_flags &= ~IFF_RUNNING;
595	    sc->sc_iferrs=0;
596	}
597
598    done:
599	splx(s);
600	return;
601}
602
603static __inline int
604lpoutbyte (u_char byte, int spin, device_t ppbus)
605{
606    ppb_wdtr(ppbus, txmith[byte]);
607    while (!(ppb_rstr(ppbus) & LPIP_SHAKE))
608	if (--spin == 0)
609		return 1;
610    ppb_wdtr(ppbus, txmitl[byte]);
611    while (ppb_rstr(ppbus) & LPIP_SHAKE)
612	if (--spin == 0)
613		return 1;
614    return 0;
615}
616
617static int
618lpoutput (struct ifnet *ifp, struct mbuf *m,
619	  struct sockaddr *dst, struct rtentry *rt)
620{
621    device_t dev = UNITODEVICE(ifp->if_unit);
622    device_t ppbus = device_get_parent(dev);
623    int s, err;
624    struct mbuf *mm;
625    u_char *cp = "\0\0";
626    u_char chksum = 0;
627    int count = 0;
628    int i, len, spin;
629
630    /* We need a sensible value if we abort */
631    cp++;
632    ifp->if_flags |= IFF_RUNNING;
633
634    err = 1;			/* assume we're aborting because of an error */
635
636    s = splhigh();
637
638    /* Suspend (on laptops) or receive-errors might have taken us offline */
639    ppb_wctr(ppbus, IRQENABLE);
640
641    if (ifp->if_flags & IFF_LINK0) {
642
643	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
644	    lprintf("&");
645	    lp_intr(dev);
646	}
647
648	/* Alert other end to pending packet */
649	spin = LPMAXSPIN1;
650	ppb_wdtr(ppbus, 0x08);
651	while ((ppb_rstr(ppbus) & 0x08) == 0)
652		if (--spin == 0) {
653			goto nend;
654		}
655
656	/* Calculate length of packet, then send that */
657
658	count += 14;		/* Ethernet header len */
659
660	mm = m;
661	for (mm = m; mm; mm = mm->m_next) {
662		count += mm->m_len;
663	}
664	if (clpoutbyte(count & 0xFF, LPMAXSPIN1, ppbus))
665		goto nend;
666	if (clpoutbyte((count >> 8) & 0xFF, LPMAXSPIN1, ppbus))
667		goto nend;
668
669	/* Send dummy ethernet header */
670	for (i = 0; i < 12; i++) {
671		if (clpoutbyte(i, LPMAXSPIN1, ppbus))
672			goto nend;
673		chksum += i;
674	}
675
676	if (clpoutbyte(0x08, LPMAXSPIN1, ppbus))
677		goto nend;
678	if (clpoutbyte(0x00, LPMAXSPIN1, ppbus))
679		goto nend;
680	chksum += 0x08 + 0x00;		/* Add into checksum */
681
682	mm = m;
683	do {
684		cp = mtod(mm, u_char *);
685		len = mm->m_len;
686		while (len--) {
687			chksum += *cp;
688			if (clpoutbyte(*cp++, LPMAXSPIN2, ppbus))
689				goto nend;
690		}
691	} while ((mm = mm->m_next));
692
693	/* Send checksum */
694	if (clpoutbyte(chksum, LPMAXSPIN2, ppbus))
695		goto nend;
696
697	/* Go quiescent */
698	ppb_wdtr(ppbus, 0);
699
700	err = 0;			/* No errors */
701
702	nend:
703	if (err)  {				/* if we didn't timeout... */
704		ifp->if_oerrors++;
705		lprintf("X");
706	} else {
707		ifp->if_opackets++;
708		ifp->if_obytes += m->m_pkthdr.len;
709		if (ifp->if_bpf)
710		    lptap(ifp, m);
711	}
712
713	m_freem(m);
714
715	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
716		lprintf("^");
717		lp_intr(dev);
718	}
719	(void) splx(s);
720	return 0;
721    }
722
723    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
724        lprintf("&");
725        lp_intr(dev);
726    }
727
728    if (lpoutbyte(0x08, LPMAXSPIN1, ppbus))
729        goto end;
730    if (lpoutbyte(0x00, LPMAXSPIN2, ppbus))
731        goto end;
732
733    mm = m;
734    do {
735        cp = mtod(mm,u_char *);
736	len = mm->m_len;
737        while (len--)
738	    if (lpoutbyte(*cp++, LPMAXSPIN2, ppbus))
739	        goto end;
740    } while ((mm = mm->m_next));
741
742    err = 0;				/* no errors were encountered */
743
744    end:
745    --cp;
746    ppb_wdtr(ppbus, txmitl[*cp] ^ 0x17);
747
748    if (err)  {				/* if we didn't timeout... */
749	ifp->if_oerrors++;
750        lprintf("X");
751    } else {
752	ifp->if_opackets++;
753	ifp->if_obytes += m->m_pkthdr.len;
754	if (ifp->if_bpf)
755	    lptap(ifp, m);
756    }
757
758    m_freem(m);
759
760    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
761	lprintf("^");
762	lp_intr(dev);
763    }
764
765    (void) splx(s);
766    return 0;
767}
768
769static device_method_t lp_methods[] = {
770  	/* device interface */
771	DEVMETHOD(device_identify,	lp_identify),
772	DEVMETHOD(device_probe,		lp_probe),
773	DEVMETHOD(device_attach,	lp_attach),
774
775	{ 0, 0 }
776};
777
778static driver_t lp_driver = {
779  "plip",
780  lp_methods,
781  sizeof(struct lp_data),
782};
783
784DRIVER_MODULE(plip, ppbus, lp_driver, lp_devclass, 0, 0);
785