if_plip.c revision 121775 
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 121775 2003-10-30 23:30:35Z 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	ifp->if_name = "lp";
237	ifp->if_unit = device_get_unit(dev);
238	ifp->if_mtu = LPMTU;
239	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
240	ifp->if_ioctl = lpioctl;
241	ifp->if_output = lpoutput;
242	ifp->if_type = IFT_PARA;
243	ifp->if_hdrlen = 0;
244	ifp->if_addrlen = 0;
245	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
246	if_attach(ifp);
247
248	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
249
250	return (0);
251}
252/*
253 * Build the translation tables for the LPIP (BSD unix) protocol.
254 * We don't want to calculate these nasties in our tight loop, so we
255 * precalculate them when we initialize.
256 */
257static int
258lpinittables (void)
259{
260    int i;
261
262    if (!txmith)
263	txmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
264
265    if (!txmith)
266	return 1;
267
268    if (!ctxmith)
269	ctxmith = malloc(4*LPIPTBLSIZE, M_DEVBUF, M_NOWAIT);
270
271    if (!ctxmith)
272	return 1;
273
274    for (i=0; i < LPIPTBLSIZE; i++) {
275	ctxmith[i] = (i & 0xF0) >> 4;
276	ctxmitl[i] = 0x10 | (i & 0x0F);
277	ctrecvh[i] = (i & 0x78) << 1;
278	ctrecvl[i] = (i & 0x78) >> 3;
279    }
280
281    for (i=0; i < LPIPTBLSIZE; i++) {
282	txmith[i] = ((i & 0x80) >> 3) | ((i & 0x70) >> 4) | 0x08;
283	txmitl[i] = ((i & 0x08) << 1) | (i & 0x07);
284	trecvh[i] = ((~i) & 0x80) | ((i & 0x38) << 1);
285	trecvl[i] = (((~i) & 0x80) >> 4) | ((i & 0x38) >> 3);
286    }
287
288    return 0;
289}
290
291/*
292 * Process an ioctl request.
293 */
294
295static int
296lpioctl (struct ifnet *ifp, u_long cmd, caddr_t data)
297{
298    device_t dev = UNITODEVICE(ifp->if_unit);
299    device_t ppbus = device_get_parent(dev);
300    struct lp_data *sc = DEVTOSOFTC(dev);
301    struct ifaddr *ifa = (struct ifaddr *)data;
302    struct ifreq *ifr = (struct ifreq *)data;
303    u_char *ptr;
304    void *ih;
305    int error;
306
307    switch (cmd) {
308
309    case SIOCSIFDSTADDR:
310    case SIOCAIFADDR:
311    case SIOCSIFADDR:
312	if (ifa->ifa_addr->sa_family != AF_INET)
313	    return EAFNOSUPPORT;
314
315	ifp->if_flags |= IFF_UP;
316	/* FALLTHROUGH */
317    case SIOCSIFFLAGS:
318	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
319
320	    ppb_wctr(ppbus, 0x00);
321	    ifp->if_flags &= ~IFF_RUNNING;
322
323	    /* IFF_UP is not set, try to release the bus anyway */
324	    ppb_release_bus(ppbus, dev);
325	    break;
326	}
327	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
328
329	    /* XXX
330	     * Should the request be interruptible?
331	     */
332	    if ((error = ppb_request_bus(ppbus, dev, PPB_WAIT|PPB_INTR)))
333		return (error);
334
335	    /* Now IFF_UP means that we own the bus */
336
337	    ppb_set_mode(ppbus, PPB_COMPATIBLE);
338
339	    if (lpinittables()) {
340		ppb_release_bus(ppbus, dev);
341		return ENOBUFS;
342	    }
343
344	    sc->sc_ifbuf = malloc(sc->sc_if.if_mtu + MLPIPHDRLEN,
345				  M_DEVBUF, M_WAITOK);
346	    if (!sc->sc_ifbuf) {
347		ppb_release_bus(ppbus, dev);
348		return ENOBUFS;
349	    }
350
351	    /* attach our interrupt handler, later detached when the bus is released */
352	    if ((error = BUS_SETUP_INTR(ppbus, dev, sc->res_irq,
353					INTR_TYPE_NET, lp_intr, dev, &ih))) {
354		ppb_release_bus(ppbus, dev);
355		return (error);
356	    }
357
358	    ppb_wctr(ppbus, IRQENABLE);
359	    ifp->if_flags |= IFF_RUNNING;
360	}
361	break;
362
363    case SIOCSIFMTU:
364	ptr = sc->sc_ifbuf;
365	sc->sc_ifbuf = malloc(ifr->ifr_mtu+MLPIPHDRLEN, M_DEVBUF, M_NOWAIT);
366	if (!sc->sc_ifbuf) {
367	    sc->sc_ifbuf = ptr;
368	    return ENOBUFS;
369	}
370	if (ptr)
371	    free(ptr,M_DEVBUF);
372	sc->sc_if.if_mtu = ifr->ifr_mtu;
373	break;
374
375    case SIOCGIFMTU:
376	ifr->ifr_mtu = sc->sc_if.if_mtu;
377	break;
378
379    case SIOCADDMULTI:
380    case SIOCDELMULTI:
381	if (ifr == 0) {
382	    return EAFNOSUPPORT;		/* XXX */
383	}
384	switch (ifr->ifr_addr.sa_family) {
385
386	case AF_INET:
387	    break;
388
389	default:
390	    return EAFNOSUPPORT;
391	}
392	break;
393
394    case SIOCGIFMEDIA:
395	/*
396	 * No ifmedia support at this stage; maybe use it
397	 * in future for eg. protocol selection.
398	 */
399	return EINVAL;
400
401    default:
402	lprintf("LP:ioctl(0x%lx)\n", cmd);
403	return EINVAL;
404    }
405    return 0;
406}
407
408static __inline int
409clpoutbyte (u_char byte, int spin, device_t ppbus)
410{
411	ppb_wdtr(ppbus, ctxmitl[byte]);
412	while (ppb_rstr(ppbus) & CLPIP_SHAKE)
413		if (--spin == 0) {
414			return 1;
415		}
416	ppb_wdtr(ppbus, ctxmith[byte]);
417	while (!(ppb_rstr(ppbus) & CLPIP_SHAKE))
418		if (--spin == 0) {
419			return 1;
420		}
421	return 0;
422}
423
424static __inline int
425clpinbyte (int spin, device_t ppbus)
426{
427	u_char c, cl;
428
429	while((ppb_rstr(ppbus) & CLPIP_SHAKE))
430	    if(!--spin) {
431		return -1;
432	    }
433	cl = ppb_rstr(ppbus);
434	ppb_wdtr(ppbus, 0x10);
435
436	while(!(ppb_rstr(ppbus) & CLPIP_SHAKE))
437	    if(!--spin) {
438		return -1;
439	    }
440	c = ppb_rstr(ppbus);
441	ppb_wdtr(ppbus, 0x00);
442
443	return (ctrecvl[cl] | ctrecvh[c]);
444}
445
446static void
447lptap(struct ifnet *ifp, struct mbuf *m)
448{
449	/*
450	 * Send a packet through bpf. We need to prepend the address family
451	 * as a four byte field. Cons up a dummy header to pacify bpf. This
452	 * is safe because bpf will only read from the mbuf (i.e., it won't
453	 * try to free it or keep a pointer to it).
454	 */
455	u_int32_t af = AF_INET;
456	struct mbuf m0;
457
458	m0.m_next = m;
459	m0.m_len = sizeof(u_int32_t);
460	m0.m_data = (char *)&af;
461	BPF_MTAP(ifp, &m0);
462}
463
464static void
465lp_intr (void *arg)
466{
467	device_t dev = (device_t)arg;
468        device_t ppbus = device_get_parent(dev);
469	struct lp_data *sc = DEVTOSOFTC(dev);
470	int len, s, j;
471	u_char *bp;
472	u_char c, cl;
473	struct mbuf *top;
474
475	s = splhigh();
476
477	if (sc->sc_if.if_flags & IFF_LINK0) {
478
479	    /* Ack. the request */
480	    ppb_wdtr(ppbus, 0x01);
481
482	    /* Get the packet length */
483	    j = clpinbyte(LPMAXSPIN2, ppbus);
484	    if (j == -1)
485		goto err;
486	    len = j;
487	    j = clpinbyte(LPMAXSPIN2, ppbus);
488	    if (j == -1)
489		goto err;
490	    len = len + (j << 8);
491	    if (len > sc->sc_if.if_mtu + MLPIPHDRLEN)
492		goto err;
493
494	    bp  = sc->sc_ifbuf;
495
496	    while (len--) {
497	        j = clpinbyte(LPMAXSPIN2, ppbus);
498	        if (j == -1) {
499		    goto err;
500	        }
501	        *bp++ = j;
502	    }
503	    /* Get and ignore checksum */
504	    j = clpinbyte(LPMAXSPIN2, ppbus);
505	    if (j == -1) {
506	        goto err;
507	    }
508
509	    len = bp - sc->sc_ifbuf;
510	    if (len <= CLPIPHDRLEN)
511	        goto err;
512
513	    sc->sc_iferrs = 0;
514
515	    len -= CLPIPHDRLEN;
516	    sc->sc_if.if_ipackets++;
517	    sc->sc_if.if_ibytes += len;
518	    top = m_devget(sc->sc_ifbuf + CLPIPHDRLEN, len, 0, &sc->sc_if, 0);
519	    if (top) {
520		if (sc->sc_if.if_bpf)
521		    lptap(&sc->sc_if, top);
522		netisr_queue(NETISR_IP, top);
523	    }
524	    goto done;
525	}
526	while ((ppb_rstr(ppbus) & LPIP_SHAKE)) {
527	    len = sc->sc_if.if_mtu + LPIPHDRLEN;
528	    bp  = sc->sc_ifbuf;
529	    while (len--) {
530
531		cl = ppb_rstr(ppbus);
532		ppb_wdtr(ppbus, 8);
533
534		j = LPMAXSPIN2;
535		while((ppb_rstr(ppbus) & LPIP_SHAKE))
536		    if(!--j) goto err;
537
538		c = ppb_rstr(ppbus);
539		ppb_wdtr(ppbus, 0);
540
541		*bp++= trecvh[cl] | trecvl[c];
542
543		j = LPMAXSPIN2;
544		while (!((cl=ppb_rstr(ppbus)) & LPIP_SHAKE)) {
545		    if (cl != c &&
546			(((cl = ppb_rstr(ppbus)) ^ 0xb8) & 0xf8) ==
547			  (c & 0xf8))
548			goto end;
549		    if (!--j) goto err;
550		}
551	    }
552
553	end:
554	    len = bp - sc->sc_ifbuf;
555	    if (len <= LPIPHDRLEN)
556		goto err;
557
558	    sc->sc_iferrs = 0;
559
560	    len -= LPIPHDRLEN;
561	    sc->sc_if.if_ipackets++;
562	    sc->sc_if.if_ibytes += len;
563	    top = m_devget(sc->sc_ifbuf + LPIPHDRLEN, len, 0, &sc->sc_if, 0);
564	    if (top) {
565		if (sc->sc_if.if_bpf)
566		    lptap(&sc->sc_if, top);
567		netisr_queue(NETISR_IP, top);
568	    }
569	}
570	goto done;
571
572    err:
573	ppb_wdtr(ppbus, 0);
574	lprintf("R");
575	sc->sc_if.if_ierrors++;
576	sc->sc_iferrs++;
577
578	/*
579	 * We are not able to send receive anything for now,
580	 * so stop wasting our time
581	 */
582	if (sc->sc_iferrs > LPMAXERRS) {
583	    printf("lp%d: Too many errors, Going off-line.\n", device_get_unit(dev));
584	    ppb_wctr(ppbus, 0x00);
585	    sc->sc_if.if_flags &= ~IFF_RUNNING;
586	    sc->sc_iferrs=0;
587	}
588
589    done:
590	splx(s);
591	return;
592}
593
594static __inline int
595lpoutbyte (u_char byte, int spin, device_t ppbus)
596{
597    ppb_wdtr(ppbus, txmith[byte]);
598    while (!(ppb_rstr(ppbus) & LPIP_SHAKE))
599	if (--spin == 0)
600		return 1;
601    ppb_wdtr(ppbus, txmitl[byte]);
602    while (ppb_rstr(ppbus) & LPIP_SHAKE)
603	if (--spin == 0)
604		return 1;
605    return 0;
606}
607
608static int
609lpoutput (struct ifnet *ifp, struct mbuf *m,
610	  struct sockaddr *dst, struct rtentry *rt)
611{
612    device_t dev = UNITODEVICE(ifp->if_unit);
613    device_t ppbus = device_get_parent(dev);
614    int s, err;
615    struct mbuf *mm;
616    u_char *cp = "\0\0";
617    u_char chksum = 0;
618    int count = 0;
619    int i, len, spin;
620
621    /* We need a sensible value if we abort */
622    cp++;
623    ifp->if_flags |= IFF_RUNNING;
624
625    err = 1;			/* assume we're aborting because of an error */
626
627    s = splhigh();
628
629    /* Suspend (on laptops) or receive-errors might have taken us offline */
630    ppb_wctr(ppbus, IRQENABLE);
631
632    if (ifp->if_flags & IFF_LINK0) {
633
634	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
635	    lprintf("&");
636	    lp_intr(dev);
637	}
638
639	/* Alert other end to pending packet */
640	spin = LPMAXSPIN1;
641	ppb_wdtr(ppbus, 0x08);
642	while ((ppb_rstr(ppbus) & 0x08) == 0)
643		if (--spin == 0) {
644			goto nend;
645		}
646
647	/* Calculate length of packet, then send that */
648
649	count += 14;		/* Ethernet header len */
650
651	mm = m;
652	for (mm = m; mm; mm = mm->m_next) {
653		count += mm->m_len;
654	}
655	if (clpoutbyte(count & 0xFF, LPMAXSPIN1, ppbus))
656		goto nend;
657	if (clpoutbyte((count >> 8) & 0xFF, LPMAXSPIN1, ppbus))
658		goto nend;
659
660	/* Send dummy ethernet header */
661	for (i = 0; i < 12; i++) {
662		if (clpoutbyte(i, LPMAXSPIN1, ppbus))
663			goto nend;
664		chksum += i;
665	}
666
667	if (clpoutbyte(0x08, LPMAXSPIN1, ppbus))
668		goto nend;
669	if (clpoutbyte(0x00, LPMAXSPIN1, ppbus))
670		goto nend;
671	chksum += 0x08 + 0x00;		/* Add into checksum */
672
673	mm = m;
674	do {
675		cp = mtod(mm, u_char *);
676		len = mm->m_len;
677		while (len--) {
678			chksum += *cp;
679			if (clpoutbyte(*cp++, LPMAXSPIN2, ppbus))
680				goto nend;
681		}
682	} while ((mm = mm->m_next));
683
684	/* Send checksum */
685	if (clpoutbyte(chksum, LPMAXSPIN2, ppbus))
686		goto nend;
687
688	/* Go quiescent */
689	ppb_wdtr(ppbus, 0);
690
691	err = 0;			/* No errors */
692
693	nend:
694	if (err)  {				/* if we didn't timeout... */
695		ifp->if_oerrors++;
696		lprintf("X");
697	} else {
698		ifp->if_opackets++;
699		ifp->if_obytes += m->m_pkthdr.len;
700		if (ifp->if_bpf)
701		    lptap(ifp, m);
702	}
703
704	m_freem(m);
705
706	if (!(ppb_rstr(ppbus) & CLPIP_SHAKE)) {
707		lprintf("^");
708		lp_intr(dev);
709	}
710	(void) splx(s);
711	return 0;
712    }
713
714    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
715        lprintf("&");
716        lp_intr(dev);
717    }
718
719    if (lpoutbyte(0x08, LPMAXSPIN1, ppbus))
720        goto end;
721    if (lpoutbyte(0x00, LPMAXSPIN2, ppbus))
722        goto end;
723
724    mm = m;
725    do {
726        cp = mtod(mm,u_char *);
727	len = mm->m_len;
728        while (len--)
729	    if (lpoutbyte(*cp++, LPMAXSPIN2, ppbus))
730	        goto end;
731    } while ((mm = mm->m_next));
732
733    err = 0;				/* no errors were encountered */
734
735    end:
736    --cp;
737    ppb_wdtr(ppbus, txmitl[*cp] ^ 0x17);
738
739    if (err)  {				/* if we didn't timeout... */
740	ifp->if_oerrors++;
741        lprintf("X");
742    } else {
743	ifp->if_opackets++;
744	ifp->if_obytes += m->m_pkthdr.len;
745	if (ifp->if_bpf)
746	    lptap(ifp, m);
747    }
748
749    m_freem(m);
750
751    if (ppb_rstr(ppbus) & LPIP_SHAKE) {
752	lprintf("^");
753	lp_intr(dev);
754    }
755
756    (void) splx(s);
757    return 0;
758}
759
760static device_method_t lp_methods[] = {
761  	/* device interface */
762	DEVMETHOD(device_identify,	lp_identify),
763	DEVMETHOD(device_probe,		lp_probe),
764	DEVMETHOD(device_attach,	lp_attach),
765
766	{ 0, 0 }
767};
768
769static driver_t lp_driver = {
770  "plip",
771  lp_methods,
772  sizeof(struct lp_data),
773};
774
775DRIVER_MODULE(plip, ppbus, lp_driver, lp_devclass, 0, 0);
776