if_plip.c revision 121816
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 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/dev/ppbus/if_plip.c 121816 2003-10-31 18:32:15Z brooks $");
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_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
224	device_set_desc(dev, "PLIP network interface");
225
226	return (0);
227}
228
229static int
230lp_attach (device_t dev)
231{
232	struct lp_data *lp = DEVTOSOFTC(dev);
233	struct ifnet *ifp = &lp->sc_if;
234
235	ifp->if_softc = lp;
236	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
237	ifp->if_mtu = LPMTU;
238	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
239	ifp->if_ioctl = lpioctl;
240	ifp->if_output = lpoutput;
241	ifp->if_type = IFT_PARA;
242	ifp->if_hdrlen = 0;
243	ifp->if_addrlen = 0;
244	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
245	if_attach(ifp);
246
247	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
248
249	return (0);
250}
251/*
252 * Build the translation tables for the LPIP (BSD unix) protocol.
253 * We don't want to calculate these nasties in our tight loop, so we
254 * precalculate them when we initialize.
255 */
256static int
257lpinittables (void)
258{
259    int i;
260
261    if (!txmith)
262	txmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
263
264    if (!txmith)
265	return 1;
266
267    if (!ctxmith)
268	ctxmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
269
270    if (!ctxmith)
271	return 1;
272
273    for (i=0; i < LPIPTBLSIZE; i++) {
274	ctxmith[i] = (i & 0xF0) >> 4;
275	ctxmitl[i] = 0x10 | (i & 0x0F);
276	ctrecvh[i] = (i & 0x78) << 1;
277	ctrecvl[i] = (i & 0x78) >> 3;
278    }
279
280    for (i=0; i < LPIPTBLSIZE; i++) {
281	txmith[i] = ((i & 0x80) >> 3) | ((i & 0x70) >> 4) | 0x08;
282	txmitl[i] = ((i & 0x08) << 1) | (i & 0x07);
283	trecvh[i] = ((~i) & 0x80) | ((i & 0x38) << 1);
284	trecvl[i] = (((~i) & 0x80) >> 4) | ((i & 0x38) >> 3);
285    }
286
287    return 0;
288}
289
290/*
291 * Process an ioctl request.
292 */
293
294static int
295lpioctl (struct ifnet *ifp, u_long cmd, caddr_t data)
296{
297    device_t dev = UNITODEVICE(ifp->if_dunit);
298    device_t ppbus = device_get_parent(dev);
299    struct lp_data *sc = DEVTOSOFTC(dev);
300    struct ifaddr *ifa = (struct ifaddr *)data;
301    struct ifreq *ifr = (struct ifreq *)data;
302    u_char *ptr;
303    void *ih;
304    int error;
305
306    switch (cmd) {
307
308    case SIOCSIFDSTADDR:
309    case SIOCAIFADDR:
310    case SIOCSIFADDR:
311	if (ifa->ifa_addr->sa_family != AF_INET)
312	    return EAFNOSUPPORT;
313
314	ifp->if_flags |= IFF_UP;
315	/* FALLTHROUGH */
316    case SIOCSIFFLAGS:
317	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
318
319	    ppb_wctr(ppbus, 0x00);
320	    ifp->if_flags &= ~IFF_RUNNING;
321
322	    /* IFF_UP is not set, try to release the bus anyway */
323	    ppb_release_bus(ppbus, dev);
324	    break;
325	}
326	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
327
328	    /* XXX
329	     * Should the request be interruptible?
330	     */
331	    if ((error = ppb_request_bus(ppbus, dev, PPB_WAIT|PPB_INTR)))
332		return (error);
333
334	    /* Now IFF_UP means that we own the bus */
335
336	    ppb_set_mode(ppbus, PPB_COMPATIBLE);
337
338	    if (lpinittables()) {
339		ppb_release_bus(ppbus, dev);
340		return ENOBUFS;
341	    }
342
343	    sc->sc_ifbuf = malloc(sc->sc_if.if_mtu + MLPIPHDRLEN,
344				  M_DEVBUF, M_WAITOK);
345	    if (!sc->sc_ifbuf) {
346		ppb_release_bus(ppbus, dev);
347		return ENOBUFS;
348	    }
349
350	    /* attach our interrupt handler, later detached when the bus is released */
351	    if ((error = BUS_SETUP_INTR(ppbus, dev, sc->res_irq,
352					INTR_TYPE_NET, lp_intr, dev, &ih))) {
353		ppb_release_bus(ppbus, dev);
354		return (error);
355	    }
356
357	    ppb_wctr(ppbus, IRQENABLE);
358	    ifp->if_flags |= IFF_RUNNING;
359	}
360	break;
361
362    case SIOCSIFMTU:
363	ptr = sc->sc_ifbuf;
364	sc->sc_ifbuf = malloc(ifr->ifr_mtu+MLPIPHDRLEN, M_DEVBUF, M_NOWAIT);
365	if (!sc->sc_ifbuf) {
366	    sc->sc_ifbuf = ptr;
367	    return ENOBUFS;
368	}
369	if (ptr)
370	    free(ptr,M_DEVBUF);
371	sc->sc_if.if_mtu = ifr->ifr_mtu;
372	break;
373
374    case SIOCGIFMTU:
375	ifr->ifr_mtu = sc->sc_if.if_mtu;
376	break;
377
378    case SIOCADDMULTI:
379    case SIOCDELMULTI:
380	if (ifr == 0) {
381	    return EAFNOSUPPORT;		/* XXX */
382	}
383	switch (ifr->ifr_addr.sa_family) {
384
385	case AF_INET:
386	    break;
387
388	default:
389	    return EAFNOSUPPORT;
390	}
391	break;
392
393    case SIOCGIFMEDIA:
394	/*
395	 * No ifmedia support at this stage; maybe use it
396	 * in future for eg. protocol selection.
397	 */
398	return EINVAL;
399
400    default:
401	lprintf("LP:ioctl(0x%lx)\n", cmd);
402	return EINVAL;
403    }
404    return 0;
405}
406
407static __inline int
408clpoutbyte (u_char byte, int spin, device_t ppbus)
409{
410	ppb_wdtr(ppbus, ctxmitl[byte]);
411	while (ppb_rstr(ppbus) & CLPIP_SHAKE)
412		if (--spin == 0) {
413			return 1;
414		}
415	ppb_wdtr(ppbus, ctxmith[byte]);
416	while (!(ppb_rstr(ppbus) & CLPIP_SHAKE))
417		if (--spin == 0) {
418			return 1;
419		}
420	return 0;
421}
422
423static __inline int
424clpinbyte (int spin, device_t ppbus)
425{
426	u_char c, cl;
427
428	while((ppb_rstr(ppbus) & CLPIP_SHAKE))
429	    if(!--spin) {
430		return -1;
431	    }
432	cl = ppb_rstr(ppbus);
433	ppb_wdtr(ppbus, 0x10);
434
435	while(!(ppb_rstr(ppbus) & CLPIP_SHAKE))
436	    if(!--spin) {
437		return -1;
438	    }
439	c = ppb_rstr(ppbus);
440	ppb_wdtr(ppbus, 0x00);
441
442	return (ctrecvl[cl] | ctrecvh[c]);
443}
444
445static void
446lptap(struct ifnet *ifp, struct mbuf *m)
447{
448	/*
449	 * Send a packet through bpf. We need to prepend the address family
450	 * as a four byte field. Cons up a dummy header to pacify bpf. This
451	 * is safe because bpf will only read from the mbuf (i.e., it won't
452	 * try to free it or keep a pointer to it).
453	 */
454	u_int32_t af = AF_INET;
455	struct mbuf m0;
456
457	m0.m_next = m;
458	m0.m_len = sizeof(u_int32_t);
459	m0.m_data = (char *)&af;
460	BPF_MTAP(ifp, &m0);
461}
462
463static void
464lp_intr (void *arg)
465{
466	device_t dev = (device_t)arg;
467        device_t ppbus = device_get_parent(dev);
468	struct lp_data *sc = DEVTOSOFTC(dev);
469	int len, s, j;
470	u_char *bp;
471	u_char c, cl;
472	struct mbuf *top;
473
474	s = splhigh();
475
476	if (sc->sc_if.if_flags & IFF_LINK0) {
477
478	    /* Ack. the request */
479	    ppb_wdtr(ppbus, 0x01);
480
481	    /* Get the packet length */
482	    j = clpinbyte(LPMAXSPIN2, ppbus);
483	    if (j == -1)
484		goto err;
485	    len = j;
486	    j = clpinbyte(LPMAXSPIN2, ppbus);
487	    if (j == -1)
488		goto err;
489	    len = len + (j << 8);
490	    if (len > sc->sc_if.if_mtu + MLPIPHDRLEN)
491		goto err;
492
493	    bp  = sc->sc_ifbuf;
494
495	    while (len--) {
496	        j = clpinbyte(LPMAXSPIN2, ppbus);
497	        if (j == -1) {
498		    goto err;
499	        }
500	        *bp++ = j;
501	    }
502	    /* Get and ignore checksum */
503	    j = clpinbyte(LPMAXSPIN2, ppbus);
504	    if (j == -1) {
505	        goto err;
506	    }
507
508	    len = bp - sc->sc_ifbuf;
509	    if (len <= CLPIPHDRLEN)
510	        goto err;
511
512	    sc->sc_iferrs = 0;
513
514	    len -= CLPIPHDRLEN;
515	    sc->sc_if.if_ipackets++;
516	    sc->sc_if.if_ibytes += len;
517	    top = m_devget(sc->sc_ifbuf + CLPIPHDRLEN, len, 0, &sc->sc_if, 0);
518	    if (top) {
519		if (sc->sc_if.if_bpf)
520		    lptap(&sc->sc_if, top);
521		netisr_queue(NETISR_IP, top);
522	    }
523	    goto done;
524	}
525	while ((ppb_rstr(ppbus) & LPIP_SHAKE)) {
526	    len = sc->sc_if.if_mtu + LPIPHDRLEN;
527	    bp  = sc->sc_ifbuf;
528	    while (len--) {
529
530		cl = ppb_rstr(ppbus);
531		ppb_wdtr(ppbus, 8);
532
533		j = LPMAXSPIN2;
534		while((ppb_rstr(ppbus) & LPIP_SHAKE))
535		    if(!--j) goto err;
536
537		c = ppb_rstr(ppbus);
538		ppb_wdtr(ppbus, 0);
539
540		*bp++= trecvh[cl] | trecvl[c];
541
542		j = LPMAXSPIN2;
543		while (!((cl=ppb_rstr(ppbus)) & LPIP_SHAKE)) {
544		    if (cl != c &&
545			(((cl = ppb_rstr(ppbus)) ^ 0xb8) & 0xf8) ==
546			  (c & 0xf8))
547			goto end;
548		    if (!--j) goto err;
549		}
550	    }
551
552	end:
553	    len = bp - sc->sc_ifbuf;
554	    if (len <= LPIPHDRLEN)
555		goto err;
556
557	    sc->sc_iferrs = 0;
558
559	    len -= LPIPHDRLEN;
560	    sc->sc_if.if_ipackets++;
561	    sc->sc_if.if_ibytes += len;
562	    top = m_devget(sc->sc_ifbuf + LPIPHDRLEN, len, 0, &sc->sc_if, 0);
563	    if (top) {
564		if (sc->sc_if.if_bpf)
565		    lptap(&sc->sc_if, top);
566		netisr_queue(NETISR_IP, top);
567	    }
568	}
569	goto done;
570
571    err:
572	ppb_wdtr(ppbus, 0);
573	lprintf("R");
574	sc->sc_if.if_ierrors++;
575	sc->sc_iferrs++;
576
577	/*
578	 * We are not able to send receive anything for now,
579	 * so stop wasting our time
580	 */
581	if (sc->sc_iferrs > LPMAXERRS) {
582	    printf("lp%d: Too many errors, Going off-line.\n", device_get_unit(dev));
583	    ppb_wctr(ppbus, 0x00);
584	    sc->sc_if.if_flags &= ~IFF_RUNNING;
585	    sc->sc_iferrs=0;
586	}
587
588    done:
589	splx(s);
590	return;
591}
592
593static __inline int
594lpoutbyte (u_char byte, int spin, device_t ppbus)
595{
596    ppb_wdtr(ppbus, txmith[byte]);
597    while (!(ppb_rstr(ppbus) & LPIP_SHAKE))
598	if (--spin == 0)
599		return 1;
600    ppb_wdtr(ppbus, txmitl[byte]);
601    while (ppb_rstr(ppbus) & LPIP_SHAKE)
602	if (--spin == 0)
603		return 1;
604    return 0;
605}
606
607static int
608lpoutput (struct ifnet *ifp, struct mbuf *m,
609	  struct sockaddr *dst, struct rtentry *rt)
610{
611    device_t dev = UNITODEVICE(ifp->if_dunit);
612    device_t ppbus = device_get_parent(dev);
613    int s, err;
614    struct mbuf *mm;
615    u_char *cp = "\0\0";
616    u_char chksum = 0;
617    int count = 0;
618    int i, len, spin;
619
620    /* We need a sensible value if we abort */
621    cp++;
622    ifp->if_flags |= IFF_RUNNING;
623
624    err = 1;			/* assume we're aborting because of an error */
625
626    s = splhigh();
627
628    /* Suspend (on laptops) or receive-errors might have taken us offline */
629    ppb_wctr(ppbus, IRQENABLE);
630
631    if (ifp->if_flags & IFF_LINK0) {
632
633	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
634	    lprintf("&");
635	    lp_intr(dev);
636	}
637
638	/* Alert other end to pending packet */
639	spin = LPMAXSPIN1;
640	ppb_wdtr(ppbus, 0x08);
641	while ((ppb_rstr(ppbus) & 0x08) == 0)
642		if (--spin == 0) {
643			goto nend;
644		}
645
646	/* Calculate length of packet, then send that */
647
648	count += 14;		/* Ethernet header len */
649
650	mm = m;
651	for (mm = m; mm; mm = mm->m_next) {
652		count += mm->m_len;
653	}
654	if (clpoutbyte(count & 0xFF, LPMAXSPIN1, ppbus))
655		goto nend;
656	if (clpoutbyte((count >> 8) & 0xFF, LPMAXSPIN1, ppbus))
657		goto nend;
658
659	/* Send dummy ethernet header */
660	for (i = 0; i < 12; i++) {
661		if (clpoutbyte(i, LPMAXSPIN1, ppbus))
662			goto nend;
663		chksum += i;
664	}
665
666	if (clpoutbyte(0x08, LPMAXSPIN1, ppbus))
667		goto nend;
668	if (clpoutbyte(0x00, LPMAXSPIN1, ppbus))
669		goto nend;
670	chksum += 0x08 + 0x00;		/* Add into checksum */
671
672	mm = m;
673	do {
674		cp = mtod(mm, u_char *);
675		len = mm->m_len;
676		while (len--) {
677			chksum += *cp;
678			if (clpoutbyte(*cp++, LPMAXSPIN2, ppbus))
679				goto nend;
680		}
681	} while ((mm = mm->m_next));
682
683	/* Send checksum */
684	if (clpoutbyte(chksum, LPMAXSPIN2, ppbus))
685		goto nend;
686
687	/* Go quiescent */
688	ppb_wdtr(ppbus, 0);
689
690	err = 0;			/* No errors */
691
692	nend:
693	if (err)  {				/* if we didn't timeout... */
694		ifp->if_oerrors++;
695		lprintf("X");
696	} else {
697		ifp->if_opackets++;
698		ifp->if_obytes += m->m_pkthdr.len;
699		if (ifp->if_bpf)
700		    lptap(ifp, m);
701	}
702
703	m_freem(m);
704
705	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
706		lprintf("^");
707		lp_intr(dev);
708	}
709	(void) splx(s);
710	return 0;
711    }
712
713    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
714        lprintf("&");
715        lp_intr(dev);
716    }
717
718    if (lpoutbyte(0x08, LPMAXSPIN1, ppbus))
719        goto end;
720    if (lpoutbyte(0x00, LPMAXSPIN2, ppbus))
721        goto end;
722
723    mm = m;
724    do {
725        cp = mtod(mm,u_char *);
726	len = mm->m_len;
727        while (len--)
728	    if (lpoutbyte(*cp++, LPMAXSPIN2, ppbus))
729	        goto end;
730    } while ((mm = mm->m_next));
731
732    err = 0;				/* no errors were encountered */
733
734    end:
735    --cp;
736    ppb_wdtr(ppbus, txmitl[*cp] ^ 0x17);
737
738    if (err)  {				/* if we didn't timeout... */
739	ifp->if_oerrors++;
740        lprintf("X");
741    } else {
742	ifp->if_opackets++;
743	ifp->if_obytes += m->m_pkthdr.len;
744	if (ifp->if_bpf)
745	    lptap(ifp, m);
746    }
747
748    m_freem(m);
749
750    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
751	lprintf("^");
752	lp_intr(dev);
753    }
754
755    (void) splx(s);
756    return 0;
757}
758
759static device_method_t lp_methods[] = {
760  	/* device interface */
761	DEVMETHOD(device_identify,	lp_identify),
762	DEVMETHOD(device_probe,		lp_probe),
763	DEVMETHOD(device_attach,	lp_attach),
764
765	{ 0, 0 }
766};
767
768static driver_t lp_driver = {
769  "plip",
770  lp_methods,
771  sizeof(struct lp_data),
772};
773
774DRIVER_MODULE(plip, ppbus, lp_driver, lp_devclass, 0, 0);
775