xref: /dragonfly/sys/dev/misc/lpt/lpt.c (revision 03be034e)
1 /*
2  * Copyright (c) 1990 William F. Jolitz, TeleMuse
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This software is a component of "386BSD" developed by
16  *	William F. Jolitz, TeleMuse.
17  * 4. Neither the name of the developer nor the name "386BSD"
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ
22  * AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS
23  * SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT.
24  * THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT
25  * NOT MAKE USE OF THIS WORK.
26  *
27  * FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
28  * BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN
29  * REFERENCES SUCH AS THE  "PORTING UNIX TO THE 386" SERIES
30  * (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING
31  * JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND
32  * LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE
33  * ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS
34  * OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
35  *
36  * THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``AS IS'' AND
37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE DEVELOPER BE LIABLE
40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46  * SUCH DAMAGE.
47  *
48  *	from: unknown origin, 386BSD 0.1
49  *	From Id: lpt.c,v 1.55.2.1 1996/11/12 09:08:38 phk Exp
50  *	From Id: nlpt.c,v 1.14 1999/02/08 13:55:43 des Exp
51  * $FreeBSD: src/sys/dev/ppbus/lpt.c,v 1.15.2.3 2000/07/07 00:30:40 obrien Exp $
52  * $DragonFly: src/sys/dev/misc/lpt/lpt.c,v 1.12 2005/06/16 16:21:30 joerg Exp $
53  */
54 
55 /*
56  * Device Driver for AT parallel printer port
57  * Written by William Jolitz 12/18/90
58  */
59 
60 /*
61  * Updated for ppbus by Nicolas Souchu
62  * [Mon Jul 28 1997]
63  */
64 
65 #include "opt_lpt.h"
66 
67 #include <sys/param.h>
68 #include <sys/systm.h>
69 #include <sys/module.h>
70 #include <sys/bus.h>
71 #include <sys/conf.h>
72 #include <sys/kernel.h>
73 #include <sys/uio.h>
74 #include <sys/syslog.h>
75 #include <sys/thread2.h>
76 #include <sys/malloc.h>
77 
78 #include <machine/clock.h>
79 #include <machine/bus.h>
80 #include <machine/resource.h>
81 #include <sys/rman.h>
82 
83 #include "lptio.h"
84 #include <bus/ppbus/ppbconf.h>
85 #include <bus/ppbus/ppb_1284.h>
86 #include "lpt.h"
87 #include "ppbus_if.h"
88 #include <bus/ppbus/ppbio.h>
89 
90 MALLOC_DEFINE(M_LPT, "lpt", "LPT buffers");
91 
92 #ifndef LPT_DEBUG
93 #define lprintf(args)
94 #else
95 #define lprintf(args)						\
96 		do {						\
97 			if (lptflag)				\
98 				printf args;			\
99 		} while (0)
100 static int volatile lptflag = 1;
101 #endif
102 
103 #define	LPINITRDY	4	/* wait up to 4 seconds for a ready */
104 #define	LPTOUTINITIAL	10	/* initial timeout to wait for ready 1/10 s */
105 #define	LPTOUTMAX	1	/* maximal timeout 1 s */
106 #define	BUFSIZE		1024
107 #define	BUFSTATSIZE	32
108 
109 #define	LPTUNIT(s)	((s)&0x03)
110 #define	LPTFLAGS(s)	((s)&0xfc)
111 
112 struct lpt_data {
113 	short	sc_state;
114 	/* default case: negative prime, negative ack, handshake strobe,
115 	   prime once */
116 	u_char	sc_control;
117 	char	sc_flags;
118 #define LP_UNITMASK	0x03	/* up to 4 units */
119 #define LP_POS_INIT	0x04	/* if we are a postive init signal */
120 #define LP_POS_ACK	0x08	/* if we are a positive going ack */
121 #define LP_NO_PRIME	0x10	/* don't prime the printer at all */
122 #define LP_PRIMEOPEN	0x20	/* prime on every open */
123 #define LP_AUTOLF	0x40	/* tell printer to do an automatic lf */
124 #define LP_BYPASS	0x80	/* bypass  printer ready checks */
125 	void	*sc_inbuf;
126 	void	*sc_statbuf;
127 	short	sc_xfercnt ;
128 	char	sc_primed;
129 	char	*sc_cp ;
130 	u_short	sc_irq ;	/* IRQ status of port */
131 #define LP_HAS_IRQ	0x01	/* we have an irq available */
132 #define LP_USE_IRQ	0x02	/* we are using our irq */
133 #define LP_ENABLE_IRQ	0x04	/* enable IRQ on open */
134 #define LP_ENABLE_EXT	0x10	/* we shall use advanced mode when possible */
135 	u_char	sc_backoff ;	/* time to call lptout() again */
136 
137 	struct resource *intr_resource;	/* interrupt resource */
138 	void *intr_cookie;		/* interrupt registration cookie */
139 	struct callout	sc_callout;
140 };
141 
142 #define LPT_NAME	"lpt"		/* our official name */
143 
144 static timeout_t lptout;
145 static int	lpt_port_test(device_t dev, u_char data, u_char mask);
146 static int	lpt_detect(device_t dev);
147 
148 #define DEVTOSOFTC(dev) \
149 	((struct lpt_data *)device_get_softc(dev))
150 #define UNITOSOFTC(unit) \
151 	((struct lpt_data *)devclass_get_softc(lpt_devclass, (unit)))
152 #define UNITODEVICE(unit) \
153 	(devclass_get_device(lpt_devclass, (unit)))
154 
155 static void lptintr(device_t dev);
156 static void lpt_intr(void *arg);	/* without spls */
157 
158 static devclass_t lpt_devclass;
159 
160 
161 /* bits for state */
162 #define	OPEN		(1<<0)	/* device is open */
163 #define	ASLP		(1<<1)	/* awaiting draining of printer */
164 #define	EERROR		(1<<2)	/* error was received from printer */
165 #define	OBUSY		(1<<3)	/* printer is busy doing output */
166 #define LPTOUT		(1<<4)	/* timeout while not selected */
167 #define TOUT		(1<<5)	/* timeout while not selected */
168 #define LPTINIT		(1<<6)	/* waiting to initialize for open */
169 #define INTERRUPTED	(1<<7)	/* write call was interrupted */
170 
171 #define HAVEBUS		(1<<8)	/* the driver owns the bus */
172 
173 
174 /* status masks to interrogate printer status */
175 #define RDY_MASK	(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)	/* ready ? */
176 #define LP_READY	(LPS_SEL|LPS_NBSY|LPS_NERR)
177 
178 /* Printer Ready condition  - from lpa.c */
179 /* Only used in polling code */
180 #define	LPS_INVERT	(LPS_NBSY | LPS_NACK |           LPS_SEL | LPS_NERR)
181 #define	LPS_MASK	(LPS_NBSY | LPS_NACK | LPS_OUT | LPS_SEL | LPS_NERR)
182 #define	NOT_READY(ppbus) ((ppb_rstr(ppbus)^LPS_INVERT)&LPS_MASK)
183 
184 #define	MAX_SLEEP	(hz*5)	/* Timeout while waiting for device ready */
185 #define	MAX_SPIN	20	/* Max delay for device ready in usecs */
186 
187 
188 static	d_open_t	lptopen;
189 static	d_close_t	lptclose;
190 static	d_write_t	lptwrite;
191 static	d_read_t	lptread;
192 static	d_ioctl_t	lptioctl;
193 
194 #define CDEV_MAJOR 16
195 static struct cdevsw lpt_cdevsw = {
196 	/* name */	LPT_NAME,
197 	/* maj */	CDEV_MAJOR,
198 	/* flags */	0,
199 	/* port */	NULL,
200 	/* clone */	NULL,
201 
202 	/* open */	lptopen,
203 	/* close */	lptclose,
204 	/* read */	lptread,
205 	/* write */	lptwrite,
206 	/* ioctl */	lptioctl,
207 	/* poll */	nopoll,
208 	/* mmap */	nommap,
209 	/* strategy */	nostrategy,
210 	/* dump */	nodump,
211 	/* psize */	nopsize
212 };
213 
214 static int
215 lpt_request_ppbus(device_t dev, int how)
216 {
217 	device_t ppbus = device_get_parent(dev);
218 	struct lpt_data *sc = DEVTOSOFTC(dev);
219 	int error;
220 
221 	if (sc->sc_state & HAVEBUS)
222 		return (0);
223 
224 	/* we have the bus only if the request succeded */
225 	if ((error = ppb_request_bus(ppbus, dev, how)) == 0)
226 		sc->sc_state |= HAVEBUS;
227 
228 	return (error);
229 }
230 
231 static int
232 lpt_release_ppbus(device_t dev)
233 {
234 	device_t ppbus = device_get_parent(dev);
235 	struct lpt_data *sc = DEVTOSOFTC(dev);
236 	int error = 0;
237 
238 	if ((error = ppb_release_bus(ppbus, dev)) == 0)
239 		sc->sc_state &= ~HAVEBUS;
240 
241 	return (error);
242 }
243 
244 /*
245  * Internal routine to lptprobe to do port tests of one byte value
246  */
247 static int
248 lpt_port_test(device_t ppbus, u_char data, u_char mask)
249 {
250 	int	temp, timeout;
251 
252 	data = data & mask;
253 	ppb_wdtr(ppbus, data);
254 	timeout = 10000;
255 	do {
256 		DELAY(10);
257 		temp = ppb_rdtr(ppbus) & mask;
258 	}
259 	while (temp != data && --timeout);
260 	lprintf(("out=%x\tin=%x\ttout=%d\n", data, temp, timeout));
261 	return (temp == data);
262 }
263 
264 /*
265  * Probe simplified by replacing multiple loops with a hardcoded
266  * test pattern - 1999/02/08 des@freebsd.org
267  *
268  * New lpt port probe Geoff Rehmet - Rhodes University - 14/2/94
269  * Based partially on Rod Grimes' printer probe
270  *
271  * Logic:
272  *	1) If no port address was given, use the bios detected ports
273  *	   and autodetect what ports the printers are on.
274  *	2) Otherwise, probe the data port at the address given,
275  *	   using the method in Rod Grimes' port probe.
276  *	   (Much code ripped off directly from Rod's probe.)
277  *
278  * Comments from Rod's probe:
279  * Logic:
280  *	1) You should be able to write to and read back the same value
281  *	   to the data port.  Do an alternating zeros, alternating ones,
282  *	   walking zero, and walking one test to check for stuck bits.
283  *
284  *	2) You should be able to write to and read back the same value
285  *	   to the control port lower 5 bits, the upper 3 bits are reserved
286  *	   per the IBM PC technical reference manauls and different boards
287  *	   do different things with them.  Do an alternating zeros, alternating
288  *	   ones, walking zero, and walking one test to check for stuck bits.
289  *
290  *	   Some printers drag the strobe line down when the are powered off
291  * 	   so this bit has been masked out of the control port test.
292  *
293  *	   XXX Some printers may not like a fast pulse on init or strobe, I
294  *	   don't know at this point, if that becomes a problem these bits
295  *	   should be turned off in the mask byte for the control port test.
296  *
297  *	   We are finally left with a mask of 0x14, due to some printers
298  *	   being adamant about holding other bits high ........
299  *
300  *	   Before probing the control port, we write a 0 to the data port -
301  *	   If not, some printers chuck out garbage when the strobe line
302  *	   gets toggled.
303  *
304  *	3) Set the data and control ports to a value of 0
305  *
306  *	This probe routine has been tested on Epson Lx-800, HP LJ3P,
307  *	Epson FX-1170 and C.Itoh 8510RM
308  *	printers.
309  *	Quick exit on fail added.
310  */
311 static int
312 lpt_detect(device_t dev)
313 {
314 	device_t ppbus = device_get_parent(dev);
315 
316 	static u_char	testbyte[18] = {
317 		0x55,			/* alternating zeros */
318 		0xaa,			/* alternating ones */
319 		0xfe, 0xfd, 0xfb, 0xf7,
320 		0xef, 0xdf, 0xbf, 0x7f,	/* walking zero */
321 		0x01, 0x02, 0x04, 0x08,
322 		0x10, 0x20, 0x40, 0x80	/* walking one */
323 	};
324 	int		i, error, status;
325 
326 	status = 1;				/* assume success */
327 
328 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
329 		printf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
330 		status = 0;
331 		goto end_probe;
332 	}
333 
334 	for (i = 0; i < 18 && status; i++)
335 		if (!lpt_port_test(ppbus, testbyte[i], 0xff)) {
336 			status = 0;
337 			goto end_probe;
338 		}
339 
340 end_probe:
341 	/* write 0's to control and data ports */
342 	ppb_wdtr(ppbus, 0);
343 	ppb_wctr(ppbus, 0);
344 
345 	lpt_release_ppbus(dev);
346 
347 	return (status);
348 }
349 
350 static void
351 lpt_identify(driver_t *driver, device_t parent)
352 {
353 
354 	BUS_ADD_CHILD(parent, 0, LPT_NAME, 0);
355 }
356 
357 /*
358  * lpt_probe()
359  */
360 static int
361 lpt_probe(device_t dev)
362 {
363 	struct lpt_data *sc;
364 
365 	sc = DEVTOSOFTC(dev);
366 	bzero(sc, sizeof(struct lpt_data));
367 
368 	/*
369 	 * Now, try to detect the printer.
370 	 */
371 	if (!lpt_detect(dev))
372 		return (ENXIO);
373 
374 	device_set_desc(dev, "Printer");
375 
376 	return (0);
377 }
378 
379 static int
380 lpt_attach(device_t dev)
381 {
382 	device_t ppbus = device_get_parent(dev);
383 	struct lpt_data *sc = DEVTOSOFTC(dev);
384 	int zero = 0, unit = device_get_unit(dev);
385 	int error;
386 	uintptr_t irq;
387 
388 	sc->sc_primed = 0;	/* not primed yet */
389 	callout_init(&sc->sc_callout);
390 
391 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
392 		printf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
393 		return (0);
394 	}
395 
396 	ppb_wctr(ppbus, LPC_NINIT);
397 
398 	/* check if we can use interrupt, should be done by ppc stuff */
399 	lprintf(("oldirq %x\n", sc->sc_irq));
400 
401 	/* retrieve the ppbus irq */
402 	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
403 
404 	if (irq > 0) {
405 		/* declare our interrupt handler */
406 		sc->intr_resource = bus_alloc_resource(dev, SYS_RES_IRQ,
407 						       &zero, irq, irq, 1, RF_SHAREABLE);
408 	}
409 	if (sc->intr_resource) {
410 		sc->sc_irq = LP_HAS_IRQ | LP_USE_IRQ | LP_ENABLE_IRQ;
411 		device_printf(dev, "Interrupt-driven port\n");
412 	} else {
413 		sc->sc_irq = 0;
414 		device_printf(dev, "Polled port\n");
415 	}
416 	lprintf(("irq %x %x\n", irq, sc->sc_irq));
417 
418 	lpt_release_ppbus(dev);
419 
420 	cdevsw_add(&lpt_cdevsw, LP_UNITMASK, unit);
421 	make_dev(&lpt_cdevsw, unit,
422 	    UID_ROOT, GID_WHEEL, 0600, LPT_NAME "%d", unit);
423 	make_dev(&lpt_cdevsw, unit | LP_BYPASS,
424 	    UID_ROOT, GID_WHEEL, 0600, LPT_NAME "%d.ctl", unit);
425 	return (0);
426 }
427 
428 static void
429 lptout(void *arg)
430 {
431 	device_t dev = (device_t)arg;
432 	struct lpt_data *sc = DEVTOSOFTC(dev);
433 #ifdef LPT_DEBUG
434 	device_t ppbus = device_get_parent(dev);
435 #endif
436 
437 	lprintf(("T %x ", ppb_rstr(ppbus)));
438 	if (sc->sc_state & OPEN) {
439 		sc->sc_backoff++;
440 		if (sc->sc_backoff > hz/LPTOUTMAX)
441 			sc->sc_backoff = sc->sc_backoff > hz/LPTOUTMAX;
442 		callout_reset(&sc->sc_callout, sc->sc_backoff, lptout, dev);
443 	} else {
444 		sc->sc_state &= ~TOUT;
445 	}
446 
447 	if (sc->sc_state & EERROR)
448 		sc->sc_state &= ~EERROR;
449 
450 	/*
451 	 * Avoid possible hangs due to missed interrupts
452 	 */
453 	if (sc->sc_xfercnt) {
454 		lptintr(dev);
455 	} else {
456 		sc->sc_state &= ~OBUSY;
457 		wakeup((caddr_t)dev);
458 	}
459 }
460 
461 /*
462  * lptopen -- reset the printer, then wait until it's selected and not busy.
463  *	If LP_BYPASS flag is selected, then we do not try to select the
464  *	printer -- this is just used for passing ioctls.
465  */
466 
467 static	int
468 lptopen(dev_t dev, int flags, int fmt, struct thread *p)
469 {
470 	int trys, err;
471 	u_int unit = LPTUNIT(minor(dev));
472 	struct lpt_data *sc = UNITOSOFTC(unit);
473 	device_t lptdev = UNITODEVICE(unit);
474 	device_t ppbus = device_get_parent(lptdev);
475 
476 	if (!sc)
477 		return (ENXIO);
478 
479 	if (sc->sc_state) {
480 		lprintf((LPT_NAME ": still open %x\n", sc->sc_state));
481 		return(EBUSY);
482 	} else
483 		sc->sc_state |= LPTINIT;
484 
485 	sc->sc_flags = LPTFLAGS(minor(dev));
486 
487 	/* Check for open with BYPASS flag set. */
488 	if (sc->sc_flags & LP_BYPASS) {
489 		sc->sc_state = OPEN;
490 		return(0);
491 	}
492 
493 	/* request the ppbus only if we don't have it already */
494 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0) {
495 		/* give it a chance to try later */
496 		sc->sc_state = 0;
497 		return (err);
498 	}
499 
500 	crit_enter();
501 	lprintf((LPT_NAME " flags 0x%x\n", sc->sc_flags));
502 
503 	/* set IRQ status according to ENABLE_IRQ flag
504 	 */
505 	if (sc->sc_irq & LP_ENABLE_IRQ)
506 		sc->sc_irq |= LP_USE_IRQ;
507 	else
508 		sc->sc_irq &= ~LP_USE_IRQ;
509 
510 	/* init printer */
511 	if ((sc->sc_flags & LP_NO_PRIME) == 0) {
512 		if((sc->sc_flags & LP_PRIMEOPEN) || sc->sc_primed == 0) {
513 			ppb_wctr(ppbus, 0);
514 			sc->sc_primed++;
515 			DELAY(500);
516 		}
517 	}
518 
519 	ppb_wctr(ppbus, LPC_SEL|LPC_NINIT);
520 
521 	/* wait till ready (printer running diagnostics) */
522 	trys = 0;
523 	do {
524 		/* ran out of waiting for the printer */
525 		if (trys++ >= LPINITRDY*4) {
526 			crit_exit();
527 			sc->sc_state = 0;
528 			lprintf(("status %x\n", ppb_rstr(ppbus)));
529 
530 			lpt_release_ppbus(lptdev);
531 			return (EBUSY);
532 		}
533 
534 		/* wait 1/4 second, give up if we get a signal */
535 		if (tsleep((caddr_t)lptdev, PCATCH, "lptinit", hz/4) !=
536 		    EWOULDBLOCK) {
537 			sc->sc_state = 0;
538 			crit_exit();
539 
540 			lpt_release_ppbus(lptdev);
541 			return (EBUSY);
542 		}
543 
544 		/* is printer online and ready for output */
545 	} while ((ppb_rstr(ppbus) &
546 			(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
547 					(LPS_SEL|LPS_NBSY|LPS_NERR));
548 
549 	sc->sc_control = LPC_SEL|LPC_NINIT;
550 	if (sc->sc_flags & LP_AUTOLF)
551 		sc->sc_control |= LPC_AUTOL;
552 
553 	/* enable interrupt if interrupt-driven */
554 	if (sc->sc_irq & LP_USE_IRQ)
555 		sc->sc_control |= LPC_ENA;
556 
557 	ppb_wctr(ppbus, sc->sc_control);
558 
559 	sc->sc_state = OPEN;
560 	sc->sc_inbuf = malloc(BUFSIZE, M_LPT, M_WAITOK);
561 	sc->sc_statbuf = malloc(BUFSTATSIZE, M_LPT, M_WAITOK);
562 	sc->sc_xfercnt = 0;
563 
564 	crit_exit();
565 
566 	/* release the ppbus */
567 	lpt_release_ppbus(lptdev);
568 
569 	/* only use timeout if using interrupt */
570 	lprintf(("irq %x\n", sc->sc_irq));
571 	if (sc->sc_irq & LP_USE_IRQ) {
572 		sc->sc_state |= TOUT;
573 		sc->sc_backoff = hz / LPTOUTINITIAL;
574 		callout_reset(&sc->sc_callout, sc->sc_backoff, lptout, lptdev);
575 	}
576 
577 	lprintf(("opened.\n"));
578 	return(0);
579 }
580 
581 /*
582  * lptclose -- close the device, free the local line buffer.
583  *
584  * Check for interrupted write call added.
585  */
586 
587 static	int
588 lptclose(dev_t dev, int flags, int fmt, struct thread *p)
589 {
590 	u_int unit = LPTUNIT(minor(dev));
591 	struct lpt_data *sc = UNITOSOFTC(unit);
592 	device_t lptdev = UNITODEVICE(unit);
593         device_t ppbus = device_get_parent(lptdev);
594 	int err;
595 
596 	if(sc->sc_flags & LP_BYPASS)
597 		goto end_close;
598 
599 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
600 		return (err);
601 
602 	sc->sc_state &= ~OPEN;
603 
604 	/* if the last write was interrupted, don't complete it */
605 	if((!(sc->sc_state & INTERRUPTED)) && (sc->sc_irq & LP_USE_IRQ)) {
606 		while ((ppb_rstr(ppbus) &
607 		    (LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
608 		    (LPS_SEL|LPS_NBSY|LPS_NERR) || sc->sc_xfercnt) {
609 			/* wait 1/4 second, give up if we get a signal */
610 			if (tsleep((caddr_t)lptdev, PCATCH,
611 			    "lpclose", hz) != EWOULDBLOCK) {
612 				break;
613 			}
614 		}
615 	}
616 	callout_stop(&sc->sc_callout);
617 	ppb_wctr(ppbus, LPC_NINIT);
618 	free(sc->sc_inbuf, M_LPT);
619 	free(sc->sc_statbuf, M_LPT);
620 
621 end_close:
622 	/* release the bus anyway
623 	 * unregistration of interrupt forced by release
624 	 */
625 	lpt_release_ppbus(lptdev);
626 
627 	sc->sc_state = 0;
628 	sc->sc_xfercnt = 0;
629 	lprintf(("closed.\n"));
630 	return(0);
631 }
632 
633 /*
634  * lpt_pushbytes()
635  *	Workhorse for actually spinning and writing bytes to printer
636  *	Derived from lpa.c
637  *	Originally by ?
638  *
639  *	This code is only used when we are polling the port
640  */
641 static int
642 lpt_pushbytes(device_t dev)
643 {
644 	struct lpt_data *sc = DEVTOSOFTC(dev);
645 	device_t ppbus = device_get_parent(dev);
646 	int spin, err, tic;
647 	char ch;
648 
649 	lprintf(("p"));
650 	/* loop for every character .. */
651 	while (sc->sc_xfercnt > 0) {
652 		/* printer data */
653 		ch = *(sc->sc_cp);
654 		sc->sc_cp++;
655 		sc->sc_xfercnt--;
656 
657 		/*
658 		 * Wait for printer ready.
659 		 * Loop 20 usecs testing BUSY bit, then sleep
660 		 * for exponentially increasing timeout. (vak)
661 		 */
662 		for (spin = 0; NOT_READY(ppbus) && spin < MAX_SPIN; ++spin)
663 			DELAY(1);	/* XXX delay is NOT this accurate! */
664 		if (spin >= MAX_SPIN) {
665 			tic = 0;
666 			while (NOT_READY(ppbus)) {
667 				/*
668 				 * Now sleep, every cycle a
669 				 * little longer ..
670 				 */
671 				tic = tic + tic + 1;
672 				/*
673 				 * But no more than 10 seconds. (vak)
674 				 */
675 				if (tic > MAX_SLEEP)
676 					tic = MAX_SLEEP;
677 				err = tsleep((caddr_t)dev, 0,
678 					LPT_NAME "poll", tic);
679 				if (err != EWOULDBLOCK) {
680 					return (err);
681 				}
682 			}
683 		}
684 
685 		/* output data */
686 		ppb_wdtr(ppbus, ch);
687 		/* strobe */
688 		ppb_wctr(ppbus, sc->sc_control|LPC_STB);
689 		ppb_wctr(ppbus, sc->sc_control);
690 
691 	}
692 	return(0);
693 }
694 
695 /*
696  * lptread --retrieve printer status in IEEE1284 NIBBLE mode
697  */
698 
699 static int
700 lptread(dev_t dev, struct uio *uio, int ioflag)
701 {
702         u_int	unit = LPTUNIT(minor(dev));
703 	struct lpt_data *sc = UNITOSOFTC(unit);
704 	device_t lptdev = UNITODEVICE(unit);
705         device_t ppbus = device_get_parent(lptdev);
706 	int error = 0, len;
707 
708 	if (sc->sc_flags & LP_BYPASS) {
709 		/* we can't do reads in bypass mode */
710 		return (EPERM);
711 	}
712 
713 	if ((error = ppb_1284_negociate(ppbus, PPB_NIBBLE, 0)))
714 		return (error);
715 
716 	/* read data in an other buffer, read/write may be simultaneous */
717 	len = 0;
718 	while (uio->uio_resid) {
719 		if ((error = ppb_1284_read(ppbus, PPB_NIBBLE,
720 				sc->sc_statbuf, min(BUFSTATSIZE,
721 				uio->uio_resid), &len))) {
722 			goto error;
723 		}
724 
725 		if (!len)
726 			goto error;		/* no more data */
727 
728 		if ((error = uiomove(sc->sc_statbuf, len, uio)))
729 			goto error;
730 	}
731 
732 error:
733 	ppb_1284_terminate(ppbus);
734 	return (error);
735 }
736 
737 /*
738  * lptwrite --copy a line from user space to a local buffer, then call
739  * putc to get the chars moved to the output queue.
740  *
741  * Flagging of interrupted write added.
742  */
743 
744 static	int
745 lptwrite(dev_t dev, struct uio *uio, int ioflag)
746 {
747 	unsigned n;
748 	int err;
749         u_int	unit = LPTUNIT(minor(dev));
750 	struct lpt_data *sc = UNITOSOFTC(unit);
751 	device_t lptdev = UNITODEVICE(unit);
752         device_t ppbus = device_get_parent(lptdev);
753 
754 	if(sc->sc_flags & LP_BYPASS) {
755 		/* we can't do writes in bypass mode */
756 		return(EPERM);
757 	}
758 
759 	/* request the ppbus only if we don't have it already */
760 	/* XXX interrupt registration?! */
761 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
762 		return (err);
763 
764 	/* if interrupts are working, register the handler */
765 	if (sc->sc_irq & LP_USE_IRQ) {
766 		/* register our interrupt handler */
767 		err = BUS_SETUP_INTR(ppbus, lptdev, sc->intr_resource,
768 			       INTR_TYPE_TTY, lpt_intr, lptdev,
769 			       &sc->intr_cookie, NULL);
770 		if (err) {
771 			device_printf(lptdev, "handler registration failed, polled mode.\n");
772 			sc->sc_irq &= ~LP_USE_IRQ;
773 		}
774 	}
775 
776 	sc->sc_state &= ~INTERRUPTED;
777 	while ((n = min(BUFSIZE, uio->uio_resid)) != 0) {
778 		sc->sc_cp = sc->sc_inbuf;
779 		uiomove(sc->sc_cp, n, uio);
780 		sc->sc_xfercnt = n ;
781 
782 		if (sc->sc_irq & LP_ENABLE_EXT) {
783 			/* try any extended mode */
784 			err = ppb_write(ppbus, sc->sc_cp,
785 					sc->sc_xfercnt, 0);
786 			switch (err) {
787 			case 0:
788 				/* if not all data was sent, we could rely
789 				 * on polling for the last bytes */
790 				sc->sc_xfercnt = 0;
791 				break;
792 			case EINTR:
793 				sc->sc_state |= INTERRUPTED;
794 				return(err);
795 			case EINVAL:
796 				/* advanced mode not avail */
797 				log(LOG_NOTICE, LPT_NAME "%d: advanced mode not avail, polling\n", unit);
798 				break;
799 			default:
800 				return(err);
801 			}
802 		} else while ((sc->sc_xfercnt > 0)&&(sc->sc_irq & LP_USE_IRQ)) {
803 			lprintf(("i"));
804 			/* if the printer is ready for a char, */
805 			/* give it one */
806 			if ((sc->sc_state & OBUSY) == 0){
807 				lprintf(("\nC %d. ", sc->sc_xfercnt));
808 				lptintr(lptdev);
809 			}
810 			lprintf(("W "));
811 			if (sc->sc_state & OBUSY)
812 				if ((err = tsleep((caddr_t)lptdev,
813 					 PCATCH, LPT_NAME "write", 0))) {
814 					sc->sc_state |= INTERRUPTED;
815 					return(err);
816 				}
817 		}
818 
819 		/* check to see if we must do a polled write */
820 		if(!(sc->sc_irq & LP_USE_IRQ) && (sc->sc_xfercnt)) {
821 			lprintf(("p"));
822 
823 			err = lpt_pushbytes(lptdev);
824 
825 			if (err)
826 				return(err);
827 		}
828 	}
829 
830 	/* we have not been interrupted, release the ppbus */
831 	lpt_release_ppbus(lptdev);
832 
833 	return(0);
834 }
835 
836 /*
837  * lpt_intr -- handle printer interrupts which occur when the printer is
838  * ready to accept another char.
839  *
840  * do checking for interrupted write call.
841  */
842 
843 static void
844 lpt_intr(void *arg)
845 {
846 	device_t lptdev = (device_t)arg;
847         device_t ppbus = device_get_parent(lptdev);
848 	struct lpt_data *sc = DEVTOSOFTC(lptdev);
849 	int sts = 0;
850 	int i;
851 
852 	/* we must own the bus to use it */
853 	if ((sc->sc_state & HAVEBUS) == 0)
854 		return;
855 
856 	/*
857 	 * Is printer online and ready for output?
858 	 *
859 	 * Avoid falling back to lptout() too quickly.  First spin-loop
860 	 * to see if the printer will become ready ``really soon now''.
861 	 */
862 	for (i = 0; i < 100 &&
863 	     ((sts=ppb_rstr(ppbus)) & RDY_MASK) != LP_READY; i++) ;
864 
865 	if ((sts & RDY_MASK) == LP_READY) {
866 		sc->sc_state = (sc->sc_state | OBUSY) & ~EERROR;
867 		sc->sc_backoff = hz/LPTOUTINITIAL;
868 
869 		if (sc->sc_xfercnt) {
870 			/* send char */
871 			/*lprintf(("%x ", *sc->sc_cp)); */
872 			ppb_wdtr(ppbus, *sc->sc_cp++) ;
873 			ppb_wctr(ppbus, sc->sc_control|LPC_STB);
874 			/* DELAY(X) */
875 			ppb_wctr(ppbus, sc->sc_control);
876 
877 			/* any more data for printer */
878 			if(--(sc->sc_xfercnt) > 0) return;
879 		}
880 
881 		/*
882 		 * No more data waiting for printer.
883 		 * Wakeup is not done if write call was not interrupted.
884 		 */
885 		sc->sc_state &= ~OBUSY;
886 
887 		if(!(sc->sc_state & INTERRUPTED))
888 			wakeup((caddr_t)lptdev);
889 		lprintf(("w "));
890 		return;
891 	} else	{	/* check for error */
892 		if(((sts & (LPS_NERR | LPS_OUT) ) != LPS_NERR) &&
893 				(sc->sc_state & OPEN))
894 			sc->sc_state |= EERROR;
895 		/* lptout() will jump in and try to restart. */
896 	}
897 	lprintf(("sts %x ", sts));
898 }
899 
900 static void
901 lptintr(device_t dev)
902 {
903 	/* call the interrupt at required spl level */
904 	crit_enter();
905 
906 	lpt_intr(dev);
907 
908 	crit_exit();
909 }
910 
911 static	int
912 lptioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *p)
913 {
914 	int	error = 0;
915         u_int	unit = LPTUNIT(minor(dev));
916         struct	lpt_data *sc = UNITOSOFTC(unit);
917 	u_char	old_sc_irq;	/* old printer IRQ status */
918 
919 	switch (cmd) {
920 	case LPT_IRQ :
921 		if(sc->sc_irq & LP_HAS_IRQ) {
922 			/*
923 			 * NOTE:
924 			 * If the IRQ status is changed,
925 			 * this will only be visible on the
926 			 * next open.
927 			 *
928 			 * If interrupt status changes,
929 			 * this gets syslog'd.
930 			 */
931 			old_sc_irq = sc->sc_irq;
932 			switch(*(int*)data) {
933 			case 0:
934 				sc->sc_irq &= (~LP_ENABLE_IRQ);
935 				break;
936 			case 1:
937 				sc->sc_irq &= (~LP_ENABLE_EXT);
938 				sc->sc_irq |= LP_ENABLE_IRQ;
939 				break;
940 			case 2:
941 				/* classic irq based transfer and advanced
942 				 * modes are in conflict
943 				 */
944 				sc->sc_irq &= (~LP_ENABLE_IRQ);
945 				sc->sc_irq |= LP_ENABLE_EXT;
946 				break;
947 			case 3:
948 				sc->sc_irq &= (~LP_ENABLE_EXT);
949 				break;
950 			default:
951 				break;
952 			}
953 
954 			if (old_sc_irq != sc->sc_irq )
955 				log(LOG_NOTICE, LPT_NAME "%d: switched to %s %s mode\n",
956 					unit,
957 					(sc->sc_irq & LP_ENABLE_IRQ)?
958 					"interrupt-driven":"polled",
959 					(sc->sc_irq & LP_ENABLE_EXT)?
960 					"extended":"standard");
961 		} else /* polled port */
962 			error = EOPNOTSUPP;
963 		break;
964 	default:
965 		error = ENODEV;
966 	}
967 
968 	return(error);
969 }
970 
971 static device_method_t lpt_methods[] = {
972 	/* device interface */
973 	DEVMETHOD(device_identify,	lpt_identify),
974 	DEVMETHOD(device_probe,		lpt_probe),
975 	DEVMETHOD(device_attach,	lpt_attach),
976 
977 	{ 0, 0 }
978 };
979 
980 static driver_t lpt_driver = {
981 	LPT_NAME,
982 	lpt_methods,
983 	sizeof(struct lpt_data),
984 };
985 
986 DRIVER_MODULE(lpt, ppbus, lpt_driver, lpt_devclass, 0, 0);
987