xref: /dragonfly/sys/dev/misc/lpt/lpt.c (revision ef2b2b9d)
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  */
53 
54 /*
55  * Device Driver for AT parallel printer port
56  * Written by William Jolitz 12/18/90
57  */
58 
59 /*
60  * Updated for ppbus by Nicolas Souchu
61  * [Mon Jul 28 1997]
62  */
63 
64 #include "opt_lpt.h"
65 
66 #include <sys/param.h>
67 #include <sys/systm.h>
68 #include <sys/module.h>
69 #include <sys/bus.h>
70 #include <sys/conf.h>
71 #include <sys/device.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 #include <sys/rman.h>
78 
79 #include <machine/clock.h>
80 #include <machine/inttypes.h>
81 
82 #include "lptio.h"
83 #include <bus/ppbus/ppbconf.h>
84 #include <bus/ppbus/ppb_1284.h>
85 #include "lpt.h"
86 #include "ppbus_if.h"
87 #include <bus/ppbus/ppbio.h>
88 
89 MALLOC_DEFINE(M_LPT, "lpt", "LPT buffers");
90 
91 #ifndef LPT_DEBUG
92 #define	lprintf(args)
93 #else
94 #define	lprintf(args)						\
95 		do {						\
96 			if (lptflag)				\
97 				kprintf args;			\
98 		} while (0)
99 static int volatile lptflag = 1;
100 #endif
101 
102 #define	LPINITRDY	4	/* wait up to 4 seconds for a ready */
103 #define	LPTOUTINITIAL	10	/* initial timeout to wait for ready 1/10 s */
104 #define	LPTOUTMAX	1	/* maximal timeout 1 s */
105 #define	BUFSIZE		1024
106 #define	BUFSTATSIZE	32
107 
108 #define	LPTUNIT(s)	((s)&0x03)
109 #define	LPTFLAGS(s)	((s)&0xfc)
110 
111 struct lpt_data {
112 	short	sc_state;
113 	/* default case: negative prime, negative ack, handshake strobe,
114 	   prime once */
115 	u_char	sc_control;
116 	char	sc_flags;
117 #define	LP_UNITMASK	0x03	/* up to 4 units */
118 #define	LP_POS_INIT	0x04	/* if we are a postive init signal */
119 #define	LP_POS_ACK	0x08	/* if we are a positive going ack */
120 #define	LP_NO_PRIME	0x10	/* don't prime the printer at all */
121 #define	LP_PRIMEOPEN	0x20	/* prime on every open */
122 #define	LP_AUTOLF	0x40	/* tell printer to do an automatic lf */
123 #define	LP_BYPASS	0x80	/* bypass  printer ready checks */
124 	void	*sc_inbuf;
125 	void	*sc_statbuf;
126 	short	sc_xfercnt ;
127 	char	sc_primed;
128 	char	*sc_cp ;
129 	u_short	sc_irq ;	/* IRQ status of port */
130 #define	LP_HAS_IRQ	0x01	/* we have an irq available */
131 #define	LP_USE_IRQ	0x02	/* we are using our irq */
132 #define	LP_ENABLE_IRQ	0x04	/* enable IRQ on open */
133 #define	LP_ENABLE_EXT	0x10	/* we shall use advanced mode when possible */
134 	u_char	sc_backoff ;	/* time to call lptout() again */
135 
136 	struct resource *intr_resource;	/* interrupt resource */
137 	void *intr_cookie;		/* interrupt registration cookie */
138 	struct callout	sc_callout;
139 };
140 
141 #define	LPT_NAME	"lpt"		/* our official name */
142 
143 static timeout_t lptout;
144 static int	lpt_port_test(device_t dev, u_char data, u_char mask);
145 static int	lpt_detect(device_t dev);
146 
147 #define	DEVTOSOFTC(dev) \
148 	((struct lpt_data *)device_get_softc(dev))
149 #define	UNITOSOFTC(unit) \
150 	((struct lpt_data *)devclass_get_softc(lpt_devclass, (unit)))
151 #define	UNITODEVICE(unit) \
152 	(devclass_get_device(lpt_devclass, (unit)))
153 
154 static void lptintr(device_t dev);
155 static void lpt_intr(void *arg);	/* without spls */
156 
157 static devclass_t lpt_devclass;
158 
159 
160 /* bits for state */
161 #define	OPEN		(1<<0)	/* device is open */
162 #define	ASLP		(1<<1)	/* awaiting draining of printer */
163 #define	EERROR		(1<<2)	/* error was received from printer */
164 #define	OBUSY		(1<<3)	/* printer is busy doing output */
165 #define	LPTOUT		(1<<4)	/* timeout while not selected */
166 #define	TOUT		(1<<5)	/* timeout while not selected */
167 #define	LPTINIT		(1<<6)	/* waiting to initialize for open */
168 #define	INTERRUPTED	(1<<7)	/* write call was interrupted */
169 #define	HAVEBUS		(1<<8)	/* the driver owns the bus */
170 
171 /* status masks to interrogate printer status */
172 #define	RDY_MASK	(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)	/* ready ? */
173 #define	LP_READY	(LPS_SEL|LPS_NBSY|LPS_NERR)
174 
175 /* Printer Ready condition  - from lpa.c */
176 /* Only used in polling code */
177 #define	LPS_INVERT	(LPS_NBSY | LPS_NACK |           LPS_SEL | LPS_NERR)
178 #define	LPS_MASK	(LPS_NBSY | LPS_NACK | LPS_OUT | LPS_SEL | LPS_NERR)
179 #define	NOT_READY(ppbus) ((ppb_rstr(ppbus)^LPS_INVERT)&LPS_MASK)
180 
181 #define	MAX_SLEEP	(hz*5)	/* Timeout while waiting for device ready */
182 #define	MAX_SPIN	20	/* Max delay for device ready in usecs */
183 
184 
185 static	d_open_t	lptopen;
186 static	d_close_t	lptclose;
187 static	d_write_t	lptwrite;
188 static	d_read_t	lptread;
189 static	d_ioctl_t	lptioctl;
190 
191 static struct dev_ops lpt_ops = {
192 	{ LPT_NAME, 0, 0 },
193 	.d_open =	lptopen,
194 	.d_close =	lptclose,
195 	.d_read =	lptread,
196 	.d_write =	lptwrite,
197 	.d_ioctl =	lptioctl,
198 };
199 
200 static int
201 lpt_request_ppbus(device_t dev, int how)
202 {
203 	device_t ppbus = device_get_parent(dev);
204 	struct lpt_data *sc = DEVTOSOFTC(dev);
205 	int error;
206 
207 	if (sc->sc_state & HAVEBUS)
208 		return (0);
209 
210 	/* we have the bus only if the request succeeded */
211 	if ((error = ppb_request_bus(ppbus, dev, how)) == 0)
212 		sc->sc_state |= HAVEBUS;
213 
214 	return (error);
215 }
216 
217 static int
218 lpt_release_ppbus(device_t dev)
219 {
220 	device_t ppbus = device_get_parent(dev);
221 	struct lpt_data *sc = DEVTOSOFTC(dev);
222 	int error = 0;
223 
224 	if ((error = ppb_release_bus(ppbus, dev)) == 0)
225 		sc->sc_state &= ~HAVEBUS;
226 
227 	return (error);
228 }
229 
230 /*
231  * Internal routine to lptprobe to do port tests of one byte value
232  */
233 static int
234 lpt_port_test(device_t ppbus, u_char data, u_char mask)
235 {
236 	int	temp, timeout;
237 
238 	data = data & mask;
239 	ppb_wdtr(ppbus, data);
240 	timeout = 10000;
241 	do {
242 		DELAY(10);
243 		temp = ppb_rdtr(ppbus) & mask;
244 	}
245 	while (temp != data && --timeout);
246 	lprintf(("out=%x\tin=%x\ttout=%d\n", data, temp, timeout));
247 	return (temp == data);
248 }
249 
250 /*
251  * Probe simplified by replacing multiple loops with a hardcoded
252  * test pattern - 1999/02/08 des@freebsd.org
253  *
254  * New lpt port probe Geoff Rehmet - Rhodes University - 14/2/94
255  * Based partially on Rod Grimes' printer probe
256  *
257  * Logic:
258  *	1) If no port address was given, use the bios detected ports
259  *	   and autodetect what ports the printers are on.
260  *	2) Otherwise, probe the data port at the address given,
261  *	   using the method in Rod Grimes' port probe.
262  *	   (Much code ripped off directly from Rod's probe.)
263  *
264  * Comments from Rod's probe:
265  * Logic:
266  *	1) You should be able to write to and read back the same value
267  *	   to the data port.  Do an alternating zeros, alternating ones,
268  *	   walking zero, and walking one test to check for stuck bits.
269  *
270  *	2) You should be able to write to and read back the same value
271  *	   to the control port lower 5 bits, the upper 3 bits are reserved
272  *	   per the IBM PC technical reference manauls and different boards
273  *	   do different things with them.  Do an alternating zeros, alternating
274  *	   ones, walking zero, and walking one test to check for stuck bits.
275  *
276  *	   Some printers drag the strobe line down when the are powered off
277  * 	   so this bit has been masked out of the control port test.
278  *
279  *	   XXX Some printers may not like a fast pulse on init or strobe, I
280  *	   don't know at this point, if that becomes a problem these bits
281  *	   should be turned off in the mask byte for the control port test.
282  *
283  *	   We are finally left with a mask of 0x14, due to some printers
284  *	   being adamant about holding other bits high ........
285  *
286  *	   Before probing the control port, we write a 0 to the data port -
287  *	   If not, some printers chuck out garbage when the strobe line
288  *	   gets toggled.
289  *
290  *	3) Set the data and control ports to a value of 0
291  *
292  *	This probe routine has been tested on Epson Lx-800, HP LJ3P,
293  *	Epson FX-1170 and C.Itoh 8510RM
294  *	printers.
295  *	Quick exit on fail added.
296  */
297 static int
298 lpt_detect(device_t dev)
299 {
300 	device_t ppbus = device_get_parent(dev);
301 
302 	static u_char	testbyte[18] = {
303 		0x55,			/* alternating zeros */
304 		0xaa,			/* alternating ones */
305 		0xfe, 0xfd, 0xfb, 0xf7,
306 		0xef, 0xdf, 0xbf, 0x7f,	/* walking zero */
307 		0x01, 0x02, 0x04, 0x08,
308 		0x10, 0x20, 0x40, 0x80	/* walking one */
309 	};
310 	int		i, error, status;
311 
312 	status = 1;				/* assume success */
313 
314 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
315 		kprintf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
316 		status = 0;
317 		goto end_probe;
318 	}
319 
320 	for (i = 0; i < 18 && status; i++)
321 		if (!lpt_port_test(ppbus, testbyte[i], 0xff)) {
322 			status = 0;
323 			goto end_probe;
324 		}
325 
326 end_probe:
327 	/* write 0's to control and data ports */
328 	ppb_wdtr(ppbus, 0);
329 	ppb_wctr(ppbus, 0);
330 
331 	lpt_release_ppbus(dev);
332 
333 	return (status);
334 }
335 
336 /*
337  * lpt_probe()
338  */
339 static int
340 lpt_probe(device_t dev)
341 {
342 	struct lpt_data *sc;
343 
344 	sc = DEVTOSOFTC(dev);
345 	bzero(sc, sizeof(struct lpt_data));
346 
347 	/*
348 	 * Now, try to detect the printer.
349 	 */
350 	if (!lpt_detect(dev))
351 		return (ENXIO);
352 
353 	device_set_desc(dev, "Printer");
354 
355 	return (0);
356 }
357 
358 static int
359 lpt_attach(device_t dev)
360 {
361 	device_t ppbus = device_get_parent(dev);
362 	struct lpt_data *sc = DEVTOSOFTC(dev);
363 	int zero = 0, unit = device_get_unit(dev);
364 	int error;
365 	uintptr_t irq;
366 
367 	sc->sc_primed = 0;	/* not primed yet */
368 	callout_init(&sc->sc_callout);
369 
370 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
371 		kprintf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
372 		return (0);
373 	}
374 
375 	ppb_wctr(ppbus, LPC_NINIT);
376 
377 	/* check if we can use interrupt, should be done by ppc stuff */
378 	lprintf(("oldirq %x\n", sc->sc_irq));
379 
380 	/* retrieve the ppbus irq */
381 	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
382 
383 	if (irq > 0) {
384 		/* declare our interrupt handler */
385 		sc->intr_resource = bus_alloc_legacy_irq_resource(dev, &zero,
386 		    irq, RF_SHAREABLE);
387 	}
388 	if (sc->intr_resource) {
389 		sc->sc_irq = LP_HAS_IRQ | LP_USE_IRQ | LP_ENABLE_IRQ;
390 		device_printf(dev, "Interrupt-driven port\n");
391 	} else {
392 		sc->sc_irq = 0;
393 		device_printf(dev, "Polled port\n");
394 	}
395 	lprintf(("irq %"PRIxPTR" %x\n", irq, sc->sc_irq));
396 
397 	lpt_release_ppbus(dev);
398 
399 	make_dev(&lpt_ops, unit, UID_ROOT, GID_WHEEL,
400 		 0600, LPT_NAME "%d", unit);
401 	make_dev(&lpt_ops, unit | LP_BYPASS, UID_ROOT, GID_WHEEL,
402 		 0600, LPT_NAME "%d.ctl", unit);
403 	return (0);
404 }
405 
406 static void
407 lptout(void *arg)
408 {
409 	device_t dev = (device_t)arg;
410 	struct lpt_data *sc = DEVTOSOFTC(dev);
411 #ifdef LPT_DEBUG
412 	device_t ppbus = device_get_parent(dev);
413 #endif
414 
415 	lprintf(("T %x ", ppb_rstr(ppbus)));
416 	if (sc->sc_state & OPEN) {
417 		sc->sc_backoff++;
418 		if (sc->sc_backoff > hz/LPTOUTMAX)
419 			sc->sc_backoff = sc->sc_backoff > hz/LPTOUTMAX;
420 		callout_reset(&sc->sc_callout, sc->sc_backoff, lptout, dev);
421 	} else {
422 		sc->sc_state &= ~TOUT;
423 	}
424 
425 	if (sc->sc_state & EERROR)
426 		sc->sc_state &= ~EERROR;
427 
428 	/*
429 	 * Avoid possible hangs due to missed interrupts
430 	 */
431 	if (sc->sc_xfercnt) {
432 		lptintr(dev);
433 	} else {
434 		sc->sc_state &= ~OBUSY;
435 		wakeup((caddr_t)dev);
436 	}
437 }
438 
439 /*
440  * lptopen -- reset the printer, then wait until it's selected and not busy.
441  *	If LP_BYPASS flag is selected, then we do not try to select the
442  *	printer -- this is just used for passing ioctls.
443  */
444 
445 static	int
446 lptopen(struct dev_open_args *ap)
447 {
448 	cdev_t dev = ap->a_head.a_dev;
449 	int trys, err;
450 	u_int unit = LPTUNIT(minor(dev));
451 	struct lpt_data *sc = UNITOSOFTC(unit);
452 	device_t lptdev = UNITODEVICE(unit);
453 	device_t ppbus = device_get_parent(lptdev);
454 
455 	if (!sc)
456 		return (ENXIO);
457 
458 	if (sc->sc_state) {
459 		lprintf((LPT_NAME ": still open %x\n", sc->sc_state));
460 		return(EBUSY);
461 	} else
462 		sc->sc_state |= LPTINIT;
463 
464 	sc->sc_flags = LPTFLAGS(minor(dev));
465 
466 	/* Check for open with BYPASS flag set. */
467 	if (sc->sc_flags & LP_BYPASS) {
468 		sc->sc_state = OPEN;
469 		return(0);
470 	}
471 
472 	/* request the ppbus only if we don't have it already */
473 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0) {
474 		/* give it a chance to try later */
475 		sc->sc_state = 0;
476 		return (err);
477 	}
478 
479 	crit_enter();
480 	lprintf((LPT_NAME " flags 0x%x\n", sc->sc_flags));
481 
482 	/* set IRQ status according to ENABLE_IRQ flag
483 	 */
484 	if (sc->sc_irq & LP_ENABLE_IRQ)
485 		sc->sc_irq |= LP_USE_IRQ;
486 	else
487 		sc->sc_irq &= ~LP_USE_IRQ;
488 
489 	/* init printer */
490 	if ((sc->sc_flags & LP_NO_PRIME) == 0) {
491 		if ((sc->sc_flags & LP_PRIMEOPEN) || sc->sc_primed == 0) {
492 			ppb_wctr(ppbus, 0);
493 			sc->sc_primed++;
494 			DELAY(500);
495 		}
496 	}
497 
498 	ppb_wctr(ppbus, LPC_SEL|LPC_NINIT);
499 
500 	/* wait till ready (printer running diagnostics) */
501 	trys = 0;
502 	do {
503 		/* ran out of waiting for the printer */
504 		if (trys++ >= LPINITRDY*4) {
505 			crit_exit();
506 			sc->sc_state = 0;
507 			lprintf(("status %x\n", ppb_rstr(ppbus)));
508 
509 			lpt_release_ppbus(lptdev);
510 			return (EBUSY);
511 		}
512 
513 		/* wait 1/4 second, give up if we get a signal */
514 		if (tsleep((caddr_t)lptdev, PCATCH, "lptinit", hz/4) !=
515 		    EWOULDBLOCK) {
516 			sc->sc_state = 0;
517 			crit_exit();
518 
519 			lpt_release_ppbus(lptdev);
520 			return (EBUSY);
521 		}
522 
523 		/* is printer online and ready for output */
524 	} while ((ppb_rstr(ppbus) &
525 			(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
526 					(LPS_SEL|LPS_NBSY|LPS_NERR));
527 
528 	sc->sc_control = LPC_SEL|LPC_NINIT;
529 	if (sc->sc_flags & LP_AUTOLF)
530 		sc->sc_control |= LPC_AUTOL;
531 
532 	/* enable interrupt if interrupt-driven */
533 	if (sc->sc_irq & LP_USE_IRQ)
534 		sc->sc_control |= LPC_ENA;
535 
536 	ppb_wctr(ppbus, sc->sc_control);
537 
538 	sc->sc_state = OPEN;
539 	sc->sc_inbuf = kmalloc(BUFSIZE, M_LPT, M_WAITOK);
540 	sc->sc_statbuf = kmalloc(BUFSTATSIZE, M_LPT, M_WAITOK);
541 	sc->sc_xfercnt = 0;
542 
543 	crit_exit();
544 
545 	/* release the ppbus */
546 	lpt_release_ppbus(lptdev);
547 
548 	/* only use timeout if using interrupt */
549 	lprintf(("irq %x\n", sc->sc_irq));
550 	if (sc->sc_irq & LP_USE_IRQ) {
551 		sc->sc_state |= TOUT;
552 		sc->sc_backoff = hz / LPTOUTINITIAL;
553 		callout_reset(&sc->sc_callout, sc->sc_backoff, lptout, lptdev);
554 	}
555 
556 	lprintf(("opened.\n"));
557 	return(0);
558 }
559 
560 /*
561  * lptclose -- close the device, free the local line buffer.
562  *
563  * Check for interrupted write call added.
564  */
565 
566 static	int
567 lptclose(struct dev_close_args *ap)
568 {
569 	cdev_t dev = ap->a_head.a_dev;
570 	u_int unit = LPTUNIT(minor(dev));
571 	struct lpt_data *sc = UNITOSOFTC(unit);
572 	device_t lptdev = UNITODEVICE(unit);
573 	device_t ppbus = device_get_parent(lptdev);
574 	int err;
575 
576 	if(sc->sc_flags & LP_BYPASS)
577 		goto end_close;
578 
579 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
580 		return (err);
581 
582 	sc->sc_state &= ~OPEN;
583 
584 	/* if the last write was interrupted, don't complete it */
585 	if((!(sc->sc_state & INTERRUPTED)) && (sc->sc_irq & LP_USE_IRQ)) {
586 		while ((ppb_rstr(ppbus) &
587 		    (LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
588 		    (LPS_SEL|LPS_NBSY|LPS_NERR) || sc->sc_xfercnt) {
589 			/* wait 1/4 second, give up if we get a signal */
590 			if (tsleep((caddr_t)lptdev, PCATCH,
591 			    "lpclose", hz) != EWOULDBLOCK) {
592 				break;
593 			}
594 		}
595 	}
596 	callout_stop(&sc->sc_callout);
597 	ppb_wctr(ppbus, LPC_NINIT);
598 	kfree(sc->sc_inbuf, M_LPT);
599 	kfree(sc->sc_statbuf, M_LPT);
600 
601 end_close:
602 	/* release the bus anyway
603 	 * unregistration of interrupt forced by release
604 	 */
605 	lpt_release_ppbus(lptdev);
606 
607 	sc->sc_state = 0;
608 	sc->sc_xfercnt = 0;
609 	lprintf(("closed.\n"));
610 	return(0);
611 }
612 
613 /*
614  * lpt_pushbytes()
615  *	Workhorse for actually spinning and writing bytes to printer
616  *	Derived from lpa.c
617  *	Originally by ?
618  *
619  *	This code is only used when we are polling the port
620  */
621 static int
622 lpt_pushbytes(device_t dev)
623 {
624 	struct lpt_data *sc = DEVTOSOFTC(dev);
625 	device_t ppbus = device_get_parent(dev);
626 	int spin, err, tic;
627 	char ch;
628 
629 	lprintf(("p"));
630 	/* loop for every character .. */
631 	while (sc->sc_xfercnt > 0) {
632 		/* printer data */
633 		ch = *(sc->sc_cp);
634 		sc->sc_cp++;
635 		sc->sc_xfercnt--;
636 
637 		/*
638 		 * Wait for printer ready.
639 		 * Loop 20 usecs testing BUSY bit, then sleep
640 		 * for exponentially increasing timeout. (vak)
641 		 */
642 		for (spin = 0; NOT_READY(ppbus) && spin < MAX_SPIN; ++spin)
643 			DELAY(1);	/* XXX delay is NOT this accurate! */
644 		if (spin >= MAX_SPIN) {
645 			tic = 0;
646 			while (NOT_READY(ppbus)) {
647 				/*
648 				 * Now sleep, every cycle a
649 				 * little longer ..
650 				 */
651 				tic = tic + tic + 1;
652 				/*
653 				 * But no more than 10 seconds. (vak)
654 				 */
655 				if (tic > MAX_SLEEP)
656 					tic = MAX_SLEEP;
657 				err = tsleep((caddr_t)dev, 0,
658 					LPT_NAME "poll", tic);
659 				if (err != EWOULDBLOCK) {
660 					return (err);
661 				}
662 			}
663 		}
664 
665 		/* output data */
666 		ppb_wdtr(ppbus, ch);
667 		/* strobe */
668 		ppb_wctr(ppbus, sc->sc_control|LPC_STB);
669 		ppb_wctr(ppbus, sc->sc_control);
670 
671 	}
672 	return(0);
673 }
674 
675 /*
676  * lptread --retrieve printer status in IEEE1284 NIBBLE mode
677  */
678 
679 static int
680 lptread(struct dev_read_args *ap)
681 {
682 	cdev_t dev = ap->a_head.a_dev;
683 	struct uio *uio = ap->a_uio;
684 	u_int	unit = LPTUNIT(minor(dev));
685 	struct lpt_data *sc = UNITOSOFTC(unit);
686 	device_t lptdev = UNITODEVICE(unit);
687 	device_t ppbus = device_get_parent(lptdev);
688 	int error = 0, len;
689 
690 	if (sc->sc_flags & LP_BYPASS) {
691 		/* we can't do reads in bypass mode */
692 		return (EPERM);
693 	}
694 
695 	if ((error = ppb_1284_negotiate(ppbus, PPB_NIBBLE, 0)))
696 		return (error);
697 
698 	/* read data in an other buffer, read/write may be simultaneous */
699 	len = 0;
700 	while (uio->uio_resid) {
701 		error = ppb_1284_read(ppbus, PPB_NIBBLE, sc->sc_statbuf,
702 				      (int)szmin(BUFSTATSIZE, uio->uio_resid),
703 				      &len);
704 		if (error)
705 			goto error;
706 
707 		if (!len)
708 			goto error;		/* no more data */
709 
710 		if ((error = uiomove(sc->sc_statbuf, (size_t)len, uio)))
711 			goto error;
712 	}
713 
714 error:
715 	ppb_1284_terminate(ppbus);
716 	return (error);
717 }
718 
719 /*
720  * lptwrite --copy a line from user space to a local buffer, then call
721  * putc to get the chars moved to the output queue.
722  *
723  * Flagging of interrupted write added.
724  */
725 
726 static	int
727 lptwrite(struct dev_write_args *ap)
728 {
729 	cdev_t dev = ap->a_head.a_dev;
730 	struct uio *uio = ap->a_uio;
731 	unsigned n;
732 	int err;
733 	u_int	unit = LPTUNIT(minor(dev));
734 	struct lpt_data *sc = UNITOSOFTC(unit);
735 	device_t lptdev = UNITODEVICE(unit);
736 	device_t ppbus = device_get_parent(lptdev);
737 
738 	if (sc->sc_flags & LP_BYPASS) {
739 		/* we can't do writes in bypass mode */
740 		return (EPERM);
741 	}
742 
743 	/* request the ppbus only if we don't have it already */
744 	/* XXX interrupt registration?! */
745 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
746 		return (err);
747 
748 	/* if interrupts are working, register the handler */
749 	if (sc->sc_irq & LP_USE_IRQ) {
750 		/* register our interrupt handler */
751 		err = BUS_SETUP_INTR(ppbus, lptdev, sc->intr_resource,
752 			       0, lpt_intr, lptdev,
753 			       &sc->intr_cookie, NULL, NULL);
754 		if (err) {
755 			device_printf(lptdev, "handler registration failed, polled mode.\n");
756 			sc->sc_irq &= ~LP_USE_IRQ;
757 		}
758 	}
759 
760 	sc->sc_state &= ~INTERRUPTED;
761 	while ((n = (unsigned)szmin(BUFSIZE, uio->uio_resid)) != 0) {
762 		sc->sc_cp = sc->sc_inbuf;
763 		uiomove(sc->sc_cp, (size_t)n, uio);
764 		sc->sc_xfercnt = n;
765 
766 		if (sc->sc_irq & LP_ENABLE_EXT) {
767 			/* try any extended mode */
768 			err = ppb_write(ppbus, sc->sc_cp,
769 					sc->sc_xfercnt, 0);
770 			switch (err) {
771 			case 0:
772 				/* if not all data was sent, we could rely
773 				 * on polling for the last bytes */
774 				sc->sc_xfercnt = 0;
775 				break;
776 			case EINTR:
777 				sc->sc_state |= INTERRUPTED;
778 				return (err);
779 			case EINVAL:
780 				/* advanced mode not avail */
781 				log(LOG_NOTICE, LPT_NAME "%d: advanced mode not avail, polling\n", unit);
782 				break;
783 			default:
784 				return (err);
785 			}
786 		} else while ((sc->sc_xfercnt > 0)&&(sc->sc_irq & LP_USE_IRQ)) {
787 			lprintf(("i"));
788 			/* if the printer is ready for a char, */
789 			/* give it one */
790 			if ((sc->sc_state & OBUSY) == 0){
791 				lprintf(("\nC %d. ", sc->sc_xfercnt));
792 				lptintr(lptdev);
793 			}
794 			lprintf(("W "));
795 			if (sc->sc_state & OBUSY)
796 				if ((err = tsleep((caddr_t)lptdev,
797 					 PCATCH, LPT_NAME "write", 0))) {
798 					sc->sc_state |= INTERRUPTED;
799 					return(err);
800 				}
801 		}
802 
803 		/* check to see if we must do a polled write */
804 		if (!(sc->sc_irq & LP_USE_IRQ) && (sc->sc_xfercnt)) {
805 			lprintf(("p"));
806 
807 			err = lpt_pushbytes(lptdev);
808 
809 			if (err)
810 				return (err);
811 		}
812 	}
813 
814 	/* we have not been interrupted, release the ppbus */
815 	lpt_release_ppbus(lptdev);
816 
817 	return (0);
818 }
819 
820 /*
821  * lpt_intr -- handle printer interrupts which occur when the printer is
822  * ready to accept another char.
823  *
824  * do checking for interrupted write call.
825  */
826 
827 static void
828 lpt_intr(void *arg)
829 {
830 	device_t lptdev = (device_t)arg;
831 	device_t ppbus = device_get_parent(lptdev);
832 	struct lpt_data *sc = DEVTOSOFTC(lptdev);
833 	int sts = 0;
834 	int i;
835 
836 	/* we must own the bus to use it */
837 	if ((sc->sc_state & HAVEBUS) == 0)
838 		return;
839 
840 	/*
841 	 * Is printer online and ready for output?
842 	 *
843 	 * Avoid falling back to lptout() too quickly.  First spin-loop
844 	 * to see if the printer will become ready ``really soon now''.
845 	 */
846 	for (i = 0; i < 100 &&
847 	     ((sts=ppb_rstr(ppbus)) & RDY_MASK) != LP_READY; i++) ;
848 
849 	if ((sts & RDY_MASK) == LP_READY) {
850 		sc->sc_state = (sc->sc_state | OBUSY) & ~EERROR;
851 		sc->sc_backoff = hz / LPTOUTINITIAL;
852 
853 		if (sc->sc_xfercnt) {
854 			/* send char */
855 			/*lprintf(("%x ", *sc->sc_cp)); */
856 			ppb_wdtr(ppbus, *sc->sc_cp++) ;
857 			ppb_wctr(ppbus, sc->sc_control|LPC_STB);
858 			/* DELAY(X) */
859 			ppb_wctr(ppbus, sc->sc_control);
860 
861 			/* any more data for printer */
862 			if (--(sc->sc_xfercnt) > 0)
863 				return;
864 		}
865 
866 		/*
867 		 * No more data waiting for printer.
868 		 * Wakeup is not done if write call was not interrupted.
869 		 */
870 		sc->sc_state &= ~OBUSY;
871 
872 		if (!(sc->sc_state & INTERRUPTED))
873 			wakeup((caddr_t)lptdev);
874 		lprintf(("w "));
875 		return;
876 	} else	{	/* check for error */
877 		if (((sts & (LPS_NERR | LPS_OUT) ) != LPS_NERR) &&
878 				(sc->sc_state & OPEN))
879 			sc->sc_state |= EERROR;
880 		/* lptout() will jump in and try to restart. */
881 	}
882 	lprintf(("sts %x ", sts));
883 }
884 
885 static void
886 lptintr(device_t dev)
887 {
888 	/* call the interrupt at required spl level */
889 	crit_enter();
890 
891 	lpt_intr(dev);
892 
893 	crit_exit();
894 }
895 
896 static	int
897 lptioctl(struct dev_ioctl_args *ap)
898 {
899 	cdev_t dev = ap->a_head.a_dev;
900 	int	error = 0;
901 	u_int	unit = LPTUNIT(minor(dev));
902 	struct	lpt_data *sc = UNITOSOFTC(unit);
903 	u_char	old_sc_irq;	/* old printer IRQ status */
904 
905 	switch (ap->a_cmd) {
906 	case LPT_IRQ :
907 		if (sc->sc_irq & LP_HAS_IRQ) {
908 			/*
909 			 * NOTE:
910 			 * If the IRQ status is changed,
911 			 * this will only be visible on the
912 			 * next open.
913 			 *
914 			 * If interrupt status changes,
915 			 * this gets syslog'd.
916 			 */
917 			old_sc_irq = sc->sc_irq;
918 			switch (*(int*)ap->a_data) {
919 			case 0:
920 				sc->sc_irq &= (~LP_ENABLE_IRQ);
921 				break;
922 			case 1:
923 				sc->sc_irq &= (~LP_ENABLE_EXT);
924 				sc->sc_irq |= LP_ENABLE_IRQ;
925 				break;
926 			case 2:
927 				/* classic irq based transfer and advanced
928 				 * modes are in conflict
929 				 */
930 				sc->sc_irq &= (~LP_ENABLE_IRQ);
931 				sc->sc_irq |= LP_ENABLE_EXT;
932 				break;
933 			case 3:
934 				sc->sc_irq &= (~LP_ENABLE_EXT);
935 				break;
936 			default:
937 				break;
938 			}
939 
940 			if (old_sc_irq != sc->sc_irq )
941 				log(LOG_NOTICE, LPT_NAME "%d: switched to %s %s mode\n",
942 					unit,
943 					(sc->sc_irq & LP_ENABLE_IRQ)?
944 					"interrupt-driven":"polled",
945 					(sc->sc_irq & LP_ENABLE_EXT)?
946 					"extended":"standard");
947 		} else /* polled port */
948 			error = EOPNOTSUPP;
949 		break;
950 	default:
951 		error = ENODEV;
952 	}
953 
954 	return(error);
955 }
956 
957 /*
958  * Because lpt is a static device that always exists under a ppbus device,
959  * and not scanned by the ppbus device, we need an identify function to
960  * install its device.
961  */
962 static device_method_t lpt_methods[] = {
963 	/* device interface */
964 	DEVMETHOD(device_identify,	bus_generic_identify),
965 	DEVMETHOD(device_probe,		lpt_probe),
966 	DEVMETHOD(device_attach,	lpt_attach),
967 
968 	DEVMETHOD_END
969 };
970 
971 static driver_t lpt_driver = {
972 	LPT_NAME,
973 	lpt_methods,
974 	sizeof(struct lpt_data),
975 };
976 
977 DRIVER_MODULE(lpt, ppbus, lpt_driver, lpt_devclass, NULL, NULL);
978