if_plip.c revision 148887 
1104483Ssam/*-
2104483Ssam * Copyright (c) 1997 Poul-Henning Kamp
3319182Sngie * All rights reserved.
4104483Ssam *
5112127Ssam * Redistribution and use in source and binary forms, with or without
6104483Ssam * modification, are permitted provided that the following conditions
7167755Ssam * are met:
8104483Ssam * 1. Redistributions of source code must retain the above copyright
9151350Syar *    notice, this list of conditions and the following disclaimer.
10112127Ssam * 2. Redistributions in binary form must reproduce the above copyright
11182668Simp *    notice, this list of conditions and the following disclaimer in the
12151350Syar *    documentation and/or other materials provided with the distribution.
13112127Ssam *
14104483Ssam * 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 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/dev/ppbus/if_plip.c 148887 2005-08-09 10:20:02Z rwatson $");
31
32/*
33 * Parallel port TCP/IP interfaces added.  I looked at the driver from
34 * MACH but this is a complete rewrite, and btw. incompatible, and it
35 * should perform better too.  I have never run the MACH driver though.
36 *
37 * This driver sends two bytes (0x08, 0x00) in front of each packet,
38 * to allow us to distinguish another format later.
39 *
40 * Now added a Linux/Crynwr compatibility mode which is enabled using
41 * IF_LINK0 - Tim Wilkinson.
42 *
43 * TODO:
44 *    Make HDLC/PPP mode, use IF_LLC1 to enable.
45 *
46 * Connect the two computers using a Laplink parallel cable to use this
47 * feature:
48 *
49 *      +----------------------------------------+
50 * 	|A-name	A-End	B-End	Descr.	Port/Bit |
51 *      +----------------------------------------+
52 *	|DATA0	2	15	Data	0/0x01   |
53 *	|-ERROR	15	2	   	1/0x08   |
54 *      +----------------------------------------+
55 *	|DATA1	3	13	Data	0/0x02	 |
56 *	|+SLCT	13	3	   	1/0x10   |
57 *      +----------------------------------------+
58 *	|DATA2	4	12	Data	0/0x04   |
59 *	|+PE	12	4	   	1/0x20   |
60 *      +----------------------------------------+
61 *	|DATA3	5	10	Strobe	0/0x08   |
62 *	|-ACK	10	5	   	1/0x40   |
63 *      +----------------------------------------+
64 *	|DATA4	6	11	Data	0/0x10   |
65 *	|BUSY	11	6	   	1/~0x80  |
66 *      +----------------------------------------+
67 *	|GND	18-25	18-25	GND	-        |
68 *      +----------------------------------------+
69 *
70 * Expect transfer-rates up to 75 kbyte/sec.
71 *
72 * If GCC could correctly grok
73 *	register int port asm("edx")
74 * the code would be cleaner
75 *
76 * Poul-Henning Kamp <phk@freebsd.org>
77 */
78
79/*
80 * Update for ppbus, PLIP support only - Nicolas Souchu
81 */
82
83#include "opt_plip.h"
84
85#include <sys/param.h>
86#include <sys/systm.h>
87#include <sys/module.h>
88#include <sys/bus.h>
89#include <sys/mbuf.h>
90#include <sys/socket.h>
91#include <sys/sockio.h>
92#include <sys/kernel.h>
93#include <sys/malloc.h>
94
95#include <machine/bus.h>
96#include <machine/resource.h>
97#include <sys/rman.h>
98
99#include <net/if.h>
100#include <net/if_types.h>
101#include <net/netisr.h>
102
103#include <netinet/in.h>
104#include <netinet/in_var.h>
105
106#include <net/bpf.h>
107
108#include <dev/ppbus/ppbconf.h>
109#include "ppbus_if.h"
110#include <dev/ppbus/ppbio.h>
111
112#ifndef LPMTU			/* MTU for the lp# interfaces */
113#define	LPMTU	1500
114#endif
115
116#ifndef LPMAXSPIN1		/* DELAY factor for the lp# interfaces */
117#define	LPMAXSPIN1	8000   /* Spinning for remote intr to happen */
118#endif
119
120#ifndef LPMAXSPIN2		/* DELAY factor for the lp# interfaces */
121#define	LPMAXSPIN2	500	/* Spinning for remote handshake to happen */
122#endif
123
124#ifndef LPMAXERRS		/* Max errors before !RUNNING */
125#define	LPMAXERRS	100
126#endif
127
128#define CLPIPHDRLEN	14	/* We send dummy ethernet addresses (two) + packet type in front of packet */
129#define	CLPIP_SHAKE	0x80	/* This bit toggles between nibble reception */
130#define MLPIPHDRLEN	CLPIPHDRLEN
131
132#define LPIPHDRLEN	2	/* We send 0x08, 0x00 in front of packet */
133#define	LPIP_SHAKE	0x40	/* This bit toggles between nibble reception */
134#if !defined(MLPIPHDRLEN) || LPIPHDRLEN > MLPIPHDRLEN
135#define MLPIPHDRLEN	LPIPHDRLEN
136#endif
137
138#define	LPIPTBLSIZE	256	/* Size of octet translation table */
139
140#define lprintf		if (lptflag) printf
141
142#ifdef PLIP_DEBUG
143static int volatile lptflag = 1;
144#else
145static int volatile lptflag = 0;
146#endif
147
148struct lp_data {
149	struct  ifnet	*sc_ifp;
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	device_t dev;
187
188	dev = device_find_child(parent, "plip", 0);
189	if (!dev)
190		BUS_ADD_CHILD(parent, 0, "plip", -1);
191}
192/*
193 * lpprobe()
194 */
195static int
196lp_probe(device_t dev)
197{
198	device_t ppbus = device_get_parent(dev);
199	struct lp_data *lp;
200	int zero = 0;
201	uintptr_t irq;
202
203	lp = DEVTOSOFTC(dev);
204
205	/* retrieve the ppbus irq */
206	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
207
208	/* if we haven't interrupts, the probe fails */
209	if (irq == -1) {
210		device_printf(dev, "not an interrupt driven port, failed.\n");
211		return (ENXIO);
212	}
213
214	/* reserve the interrupt resource, expecting irq is available to continue */
215	lp->res_irq = bus_alloc_resource(dev, SYS_RES_IRQ, &zero, irq, irq, 1,
216					 RF_SHAREABLE);
217	if (lp->res_irq == 0) {
218		device_printf(dev, "cannot reserve interrupt, failed.\n");
219		return (ENXIO);
220	}
221
222	/*
223	 * lp dependent initialisation.
224	 */
225
226	device_set_desc(dev, "PLIP network interface");
227
228	return (0);
229}
230
231static int
232lp_attach (device_t dev)
233{
234	struct lp_data *lp = DEVTOSOFTC(dev);
235	struct ifnet *ifp;
236
237	ifp = lp->sc_ifp = if_alloc(IFT_PARA);
238	if (ifp == NULL) {
239		return (ENOSPC);
240	}
241
242	ifp->if_softc = lp;
243	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
244	ifp->if_mtu = LPMTU;
245	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST |
246	    IFF_NEEDSGIANT;
247	ifp->if_ioctl = lpioctl;
248	ifp->if_output = lpoutput;
249	ifp->if_hdrlen = 0;
250	ifp->if_addrlen = 0;
251	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
252	if_attach(ifp);
253
254	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
255
256	return (0);
257}
258/*
259 * Build the translation tables for the LPIP (BSD unix) protocol.
260 * We don't want to calculate these nasties in our tight loop, so we
261 * precalculate them when we initialize.
262 */
263static int
264lpinittables (void)
265{
266    int i;
267
268    if (!txmith)
269	txmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
270
271    if (!txmith)
272	return 1;
273
274    if (!ctxmith)
275	ctxmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
276
277    if (!ctxmith)
278	return 1;
279
280    for (i=0; i < LPIPTBLSIZE; i++) {
281	ctxmith[i] = (i & 0xF0) >> 4;
282	ctxmitl[i] = 0x10 | (i & 0x0F);
283	ctrecvh[i] = (i & 0x78) << 1;
284	ctrecvl[i] = (i & 0x78) >> 3;
285    }
286
287    for (i=0; i < LPIPTBLSIZE; i++) {
288	txmith[i] = ((i & 0x80) >> 3) | ((i & 0x70) >> 4) | 0x08;
289	txmitl[i] = ((i & 0x08) << 1) | (i & 0x07);
290	trecvh[i] = ((~i) & 0x80) | ((i & 0x38) << 1);
291	trecvl[i] = (((~i) & 0x80) >> 4) | ((i & 0x38) >> 3);
292    }
293
294    return 0;
295}
296
297/*
298 * Process an ioctl request.
299 */
300
301static int
302lpioctl (struct ifnet *ifp, u_long cmd, caddr_t data)
303{
304    device_t dev = UNITODEVICE(ifp->if_dunit);
305    device_t ppbus = device_get_parent(dev);
306    struct lp_data *sc = DEVTOSOFTC(dev);
307    struct ifaddr *ifa = (struct ifaddr *)data;
308    struct ifreq *ifr = (struct ifreq *)data;
309    u_char *ptr;
310    void *ih;
311    int error;
312
313    switch (cmd) {
314
315    case SIOCSIFDSTADDR:
316    case SIOCAIFADDR:
317    case SIOCSIFADDR:
318	if (ifa->ifa_addr->sa_family != AF_INET)
319	    return EAFNOSUPPORT;
320
321	ifp->if_flags |= IFF_UP;
322	/* FALLTHROUGH */
323    case SIOCSIFFLAGS:
324	if ((!(ifp->if_flags & IFF_UP)) &&
325	  (ifp->if_drv_flags & IFF_DRV_RUNNING)) {
326
327	    ppb_wctr(ppbus, 0x00);
328	    ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
329
330	    /* IFF_UP is not set, try to release the bus anyway */
331	    ppb_release_bus(ppbus, dev);
332	    break;
333	}
334	if (((ifp->if_flags & IFF_UP)) &&
335	  (!(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
336
337	    /* XXX
338	     * Should the request be interruptible?
339	     */
340	    if ((error = ppb_request_bus(ppbus, dev, PPB_WAIT|PPB_INTR)))
341		return (error);
342
343	    /* Now IFF_UP means that we own the bus */
344
345	    ppb_set_mode(ppbus, PPB_COMPATIBLE);
346
347	    if (lpinittables()) {
348		ppb_release_bus(ppbus, dev);
349		return ENOBUFS;
350	    }
351
352	    sc->sc_ifbuf = malloc(sc->sc_ifp->if_mtu + MLPIPHDRLEN,
353				  M_DEVBUF, M_WAITOK);
354	    if (!sc->sc_ifbuf) {
355		ppb_release_bus(ppbus, dev);
356		return ENOBUFS;
357	    }
358
359	    /* attach our interrupt handler, later detached when the bus is released */
360	    if ((error = BUS_SETUP_INTR(ppbus, dev, sc->res_irq,
361					INTR_TYPE_NET, lp_intr, dev, &ih))) {
362		ppb_release_bus(ppbus, dev);
363		return (error);
364	    }
365
366	    ppb_wctr(ppbus, IRQENABLE);
367	    ifp->if_drv_flags |= IFF_DRV_RUNNING;
368	}
369	break;
370
371    case SIOCSIFMTU:
372	ptr = sc->sc_ifbuf;
373	sc->sc_ifbuf = malloc(ifr->ifr_mtu+MLPIPHDRLEN, M_DEVBUF, M_NOWAIT);
374	if (!sc->sc_ifbuf) {
375	    sc->sc_ifbuf = ptr;
376	    return ENOBUFS;
377	}
378	if (ptr)
379	    free(ptr,M_DEVBUF);
380	sc->sc_ifp->if_mtu = ifr->ifr_mtu;
381	break;
382
383    case SIOCGIFMTU:
384	ifr->ifr_mtu = sc->sc_ifp->if_mtu;
385	break;
386
387    case SIOCADDMULTI:
388    case SIOCDELMULTI:
389	if (ifr == 0) {
390	    return EAFNOSUPPORT;		/* XXX */
391	}
392	switch (ifr->ifr_addr.sa_family) {
393
394	case AF_INET:
395	    break;
396
397	default:
398	    return EAFNOSUPPORT;
399	}
400	break;
401
402    case SIOCGIFMEDIA:
403	/*
404	 * No ifmedia support at this stage; maybe use it
405	 * in future for eg. protocol selection.
406	 */
407	return EINVAL;
408
409    default:
410	lprintf("LP:ioctl(0x%lx)\n", cmd);
411	return EINVAL;
412    }
413    return 0;
414}
415
416static __inline int
417clpoutbyte (u_char byte, int spin, device_t ppbus)
418{
419	ppb_wdtr(ppbus, ctxmitl[byte]);
420	while (ppb_rstr(ppbus) & CLPIP_SHAKE)
421		if (--spin == 0) {
422			return 1;
423		}
424	ppb_wdtr(ppbus, ctxmith[byte]);
425	while (!(ppb_rstr(ppbus) & CLPIP_SHAKE))
426		if (--spin == 0) {
427			return 1;
428		}
429	return 0;
430}
431
432static __inline int
433clpinbyte (int spin, device_t ppbus)
434{
435	u_char c, cl;
436
437	while((ppb_rstr(ppbus) & CLPIP_SHAKE))
438	    if(!--spin) {
439		return -1;
440	    }
441	cl = ppb_rstr(ppbus);
442	ppb_wdtr(ppbus, 0x10);
443
444	while(!(ppb_rstr(ppbus) & CLPIP_SHAKE))
445	    if(!--spin) {
446		return -1;
447	    }
448	c = ppb_rstr(ppbus);
449	ppb_wdtr(ppbus, 0x00);
450
451	return (ctrecvl[cl] | ctrecvh[c]);
452}
453
454static void
455lptap(struct ifnet *ifp, struct mbuf *m)
456{
457	u_int32_t af = AF_INET;
458	BPF_MTAP2(ifp, &af, sizeof(af), m);
459}
460
461static void
462lp_intr (void *arg)
463{
464	device_t dev = (device_t)arg;
465        device_t ppbus = device_get_parent(dev);
466	struct lp_data *sc = DEVTOSOFTC(dev);
467	int len, s, j;
468	u_char *bp;
469	u_char c, cl;
470	struct mbuf *top;
471
472	s = splhigh();
473
474	if (sc->sc_ifp->if_flags & IFF_LINK0) {
475
476	    /* Ack. the request */
477	    ppb_wdtr(ppbus, 0x01);
478
479	    /* Get the packet length */
480	    j = clpinbyte(LPMAXSPIN2, ppbus);
481	    if (j == -1)
482		goto err;
483	    len = j;
484	    j = clpinbyte(LPMAXSPIN2, ppbus);
485	    if (j == -1)
486		goto err;
487	    len = len + (j << 8);
488	    if (len > sc->sc_ifp->if_mtu + MLPIPHDRLEN)
489		goto err;
490
491	    bp  = sc->sc_ifbuf;
492
493	    while (len--) {
494	        j = clpinbyte(LPMAXSPIN2, ppbus);
495	        if (j == -1) {
496		    goto err;
497	        }
498	        *bp++ = j;
499	    }
500	    /* Get and ignore checksum */
501	    j = clpinbyte(LPMAXSPIN2, ppbus);
502	    if (j == -1) {
503	        goto err;
504	    }
505
506	    len = bp - sc->sc_ifbuf;
507	    if (len <= CLPIPHDRLEN)
508	        goto err;
509
510	    sc->sc_iferrs = 0;
511
512	    len -= CLPIPHDRLEN;
513	    sc->sc_ifp->if_ipackets++;
514	    sc->sc_ifp->if_ibytes += len;
515	    top = m_devget(sc->sc_ifbuf + CLPIPHDRLEN, len, 0, sc->sc_ifp, 0);
516	    if (top) {
517		if (sc->sc_ifp->if_bpf)
518		    lptap(sc->sc_ifp, top);
519		netisr_queue(NETISR_IP, top);	/* mbuf is free'd on failure. */
520	    }
521	    goto done;
522	}
523	while ((ppb_rstr(ppbus) & LPIP_SHAKE)) {
524	    len = sc->sc_ifp->if_mtu + LPIPHDRLEN;
525	    bp  = sc->sc_ifbuf;
526	    while (len--) {
527
528		cl = ppb_rstr(ppbus);
529		ppb_wdtr(ppbus, 8);
530
531		j = LPMAXSPIN2;
532		while((ppb_rstr(ppbus) & LPIP_SHAKE))
533		    if(!--j) goto err;
534
535		c = ppb_rstr(ppbus);
536		ppb_wdtr(ppbus, 0);
537
538		*bp++= trecvh[cl] | trecvl[c];
539
540		j = LPMAXSPIN2;
541		while (!((cl=ppb_rstr(ppbus)) & LPIP_SHAKE)) {
542		    if (cl != c &&
543			(((cl = ppb_rstr(ppbus)) ^ 0xb8) & 0xf8) ==
544			  (c & 0xf8))
545			goto end;
546		    if (!--j) goto err;
547		}
548	    }
549
550	end:
551	    len = bp - sc->sc_ifbuf;
552	    if (len <= LPIPHDRLEN)
553		goto err;
554
555	    sc->sc_iferrs = 0;
556
557	    len -= LPIPHDRLEN;
558	    sc->sc_ifp->if_ipackets++;
559	    sc->sc_ifp->if_ibytes += len;
560	    top = m_devget(sc->sc_ifbuf + LPIPHDRLEN, len, 0, sc->sc_ifp, 0);
561	    if (top) {
562		if (sc->sc_ifp->if_bpf)
563		    lptap(sc->sc_ifp, top);
564		netisr_queue(NETISR_IP, top);	/* mbuf is free'd on failure. */
565	    }
566	}
567	goto done;
568
569    err:
570	ppb_wdtr(ppbus, 0);
571	lprintf("R");
572	sc->sc_ifp->if_ierrors++;
573	sc->sc_iferrs++;
574
575	/*
576	 * We are not able to send receive anything for now,
577	 * so stop wasting our time
578	 */
579	if (sc->sc_iferrs > LPMAXERRS) {
580	    printf("lp%d: Too many errors, Going off-line.\n", device_get_unit(dev));
581	    ppb_wctr(ppbus, 0x00);
582	    sc->sc_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
583	    sc->sc_iferrs=0;
584	}
585
586    done:
587	splx(s);
588	return;
589}
590
591static __inline int
592lpoutbyte (u_char byte, int spin, device_t ppbus)
593{
594    ppb_wdtr(ppbus, txmith[byte]);
595    while (!(ppb_rstr(ppbus) & LPIP_SHAKE))
596	if (--spin == 0)
597		return 1;
598    ppb_wdtr(ppbus, txmitl[byte]);
599    while (ppb_rstr(ppbus) & LPIP_SHAKE)
600	if (--spin == 0)
601		return 1;
602    return 0;
603}
604
605static int
606lpoutput (struct ifnet *ifp, struct mbuf *m,
607	  struct sockaddr *dst, struct rtentry *rt)
608{
609    device_t dev = UNITODEVICE(ifp->if_dunit);
610    device_t ppbus = device_get_parent(dev);
611    int s, err;
612    struct mbuf *mm;
613    u_char *cp = "\0\0";
614    u_char chksum = 0;
615    int count = 0;
616    int i, len, spin;
617
618    /* We need a sensible value if we abort */
619    cp++;
620    ifp->if_drv_flags |= IFF_DRV_RUNNING;
621
622    err = 1;			/* assume we're aborting because of an error */
623
624    s = splhigh();
625
626    /* Suspend (on laptops) or receive-errors might have taken us offline */
627    ppb_wctr(ppbus, IRQENABLE);
628
629    if (ifp->if_flags & IFF_LINK0) {
630
631	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
632	    lprintf("&");
633	    lp_intr(dev);
634	}
635
636	/* Alert other end to pending packet */
637	spin = LPMAXSPIN1;
638	ppb_wdtr(ppbus, 0x08);
639	while ((ppb_rstr(ppbus) & 0x08) == 0)
640		if (--spin == 0) {
641			goto nend;
642		}
643
644	/* Calculate length of packet, then send that */
645
646	count += 14;		/* Ethernet header len */
647
648	mm = m;
649	for (mm = m; mm; mm = mm->m_next) {
650		count += mm->m_len;
651	}
652	if (clpoutbyte(count & 0xFF, LPMAXSPIN1, ppbus))
653		goto nend;
654	if (clpoutbyte((count >> 8) & 0xFF, LPMAXSPIN1, ppbus))
655		goto nend;
656
657	/* Send dummy ethernet header */
658	for (i = 0; i < 12; i++) {
659		if (clpoutbyte(i, LPMAXSPIN1, ppbus))
660			goto nend;
661		chksum += i;
662	}
663
664	if (clpoutbyte(0x08, LPMAXSPIN1, ppbus))
665		goto nend;
666	if (clpoutbyte(0x00, LPMAXSPIN1, ppbus))
667		goto nend;
668	chksum += 0x08 + 0x00;		/* Add into checksum */
669
670	mm = m;
671	do {
672		cp = mtod(mm, u_char *);
673		len = mm->m_len;
674		while (len--) {
675			chksum += *cp;
676			if (clpoutbyte(*cp++, LPMAXSPIN2, ppbus))
677				goto nend;
678		}
679	} while ((mm = mm->m_next));
680
681	/* Send checksum */
682	if (clpoutbyte(chksum, LPMAXSPIN2, ppbus))
683		goto nend;
684
685	/* Go quiescent */
686	ppb_wdtr(ppbus, 0);
687
688	err = 0;			/* No errors */
689
690	nend:
691	if (err)  {				/* if we didn't timeout... */
692		ifp->if_oerrors++;
693		lprintf("X");
694	} else {
695		ifp->if_opackets++;
696		ifp->if_obytes += m->m_pkthdr.len;
697		if (ifp->if_bpf)
698		    lptap(ifp, m);
699	}
700
701	m_freem(m);
702
703	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
704		lprintf("^");
705		lp_intr(dev);
706	}
707	(void) splx(s);
708	return 0;
709    }
710
711    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
712        lprintf("&");
713        lp_intr(dev);
714    }
715
716    if (lpoutbyte(0x08, LPMAXSPIN1, ppbus))
717        goto end;
718    if (lpoutbyte(0x00, LPMAXSPIN2, ppbus))
719        goto end;
720
721    mm = m;
722    do {
723        cp = mtod(mm,u_char *);
724	len = mm->m_len;
725        while (len--)
726	    if (lpoutbyte(*cp++, LPMAXSPIN2, ppbus))
727	        goto end;
728    } while ((mm = mm->m_next));
729
730    err = 0;				/* no errors were encountered */
731
732    end:
733    --cp;
734    ppb_wdtr(ppbus, txmitl[*cp] ^ 0x17);
735
736    if (err)  {				/* if we didn't timeout... */
737	ifp->if_oerrors++;
738        lprintf("X");
739    } else {
740	ifp->if_opackets++;
741	ifp->if_obytes += m->m_pkthdr.len;
742	if (ifp->if_bpf)
743	    lptap(ifp, m);
744    }
745
746    m_freem(m);
747
748    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
749	lprintf("^");
750	lp_intr(dev);
751    }
752
753    (void) splx(s);
754    return 0;
755}
756
757static device_method_t lp_methods[] = {
758  	/* device interface */
759	DEVMETHOD(device_identify,	lp_identify),
760	DEVMETHOD(device_probe,		lp_probe),
761	DEVMETHOD(device_attach,	lp_attach),
762
763	{ 0, 0 }
764};
765
766static driver_t lp_driver = {
767  "plip",
768  lp_methods,
769  sizeof(struct lp_data),
770};
771
772DRIVER_MODULE(plip, ppbus, lp_driver, lp_devclass, 0, 0);
773