xref: /freebsd/sys/dev/ppbus/lpt.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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  */
52 
53 #include <sys/cdefs.h>
54 __FBSDID("$FreeBSD$");
55 
56 /*
57  * Device Driver for AT parallel printer port
58  * Written by William Jolitz 12/18/90
59  */
60 
61 /*
62  * Updated for ppbus by Nicolas Souchu
63  * [Mon Jul 28 1997]
64  */
65 
66 #include "opt_lpt.h"
67 
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/module.h>
71 #include <sys/bus.h>
72 #include <sys/conf.h>
73 #include <sys/kernel.h>
74 #include <sys/uio.h>
75 #include <sys/syslog.h>
76 #include <sys/malloc.h>
77 
78 #include <machine/bus.h>
79 #include <machine/resource.h>
80 #include <sys/rman.h>
81 
82 #include <dev/ppbus/lptio.h>
83 #include <dev/ppbus/ppbconf.h>
84 #include <dev/ppbus/ppb_1284.h>
85 #include <dev/ppbus/lpt.h>
86 #include "ppbus_if.h"
87 #include <dev/ppbus/ppbio.h>
88 
89 #ifndef LPT_DEBUG
90 #define lprintf(args)
91 #else
92 #define lprintf(args)						\
93 		do {						\
94 			if (lptflag)				\
95 				printf args;			\
96 		} while (0)
97 static int volatile lptflag = 1;
98 #endif
99 
100 #define	LPINITRDY	4	/* wait up to 4 seconds for a ready */
101 #define	LPTOUTINITIAL	10	/* initial timeout to wait for ready 1/10 s */
102 #define	LPTOUTMAX	1	/* maximal timeout 1 s */
103 #define	LPPRI		(PZERO+8)
104 #define	BUFSIZE		1024
105 #define	BUFSTATSIZE	32
106 
107 #define	LPTUNIT(s)	((s)&0x03)
108 #define	LPTFLAGS(s)	((s)&0xfc)
109 
110 struct lpt_data {
111 
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_POS_INIT	0x04	/* if we are a postive init signal */
118 #define LP_POS_ACK	0x08	/* if we are a positive going ack */
119 #define LP_NO_PRIME	0x10	/* don't prime the printer at all */
120 #define LP_PRIMEOPEN	0x20	/* prime on every open */
121 #define LP_AUTOLF	0x40	/* tell printer to do an automatic lf */
122 #define LP_BYPASS	0x80	/* bypass  printer ready checks */
123 	void	*sc_inbuf;
124 	void	*sc_statbuf;
125 	short	sc_xfercnt ;
126 	char	sc_primed;
127 	char	*sc_cp ;
128 	u_short	sc_irq ;	/* IRQ status of port */
129 #define LP_HAS_IRQ	0x01	/* we have an irq available */
130 #define LP_USE_IRQ	0x02	/* we are using our irq */
131 #define LP_ENABLE_IRQ	0x04	/* enable IRQ on open */
132 #define LP_ENABLE_EXT	0x10	/* we shall use advanced mode when possible */
133 	u_char	sc_backoff ;	/* time to call lptout() again */
134 
135 	struct resource *intr_resource;	/* interrupt resource */
136 	void *intr_cookie;		/* interrupt registration cookie */
137 
138 };
139 
140 #define LPT_NAME	"lpt"		/* our official name */
141 
142 static timeout_t lptout;
143 static int	lpt_port_test(device_t dev, u_char data, u_char mask);
144 static int	lpt_detect(device_t dev);
145 
146 #define DEVTOSOFTC(dev) \
147 	((struct lpt_data *)device_get_softc(dev))
148 #define UNITOSOFTC(unit) \
149 	((struct lpt_data *)devclass_get_softc(lpt_devclass, (unit)))
150 #define UNITODEVICE(unit) \
151 	(devclass_get_device(lpt_devclass, (unit)))
152 
153 static void lptintr(device_t dev);
154 static void lpt_intr(void *arg);	/* without spls */
155 
156 static devclass_t lpt_devclass;
157 
158 
159 /* bits for state */
160 #define	OPEN		(1<<0)	/* device is open */
161 #define	ASLP		(1<<1)	/* awaiting draining of printer */
162 #define	EERROR		(1<<2)	/* error was received from printer */
163 #define	OBUSY		(1<<3)	/* printer is busy doing output */
164 #define LPTOUT		(1<<4)	/* timeout while not selected */
165 #define TOUT		(1<<5)	/* timeout while not selected */
166 #define LPTINIT		(1<<6)	/* waiting to initialize for open */
167 #define INTERRUPTED	(1<<7)	/* write call was interrupted */
168 
169 #define HAVEBUS		(1<<8)	/* the driver owns the bus */
170 
171 
172 /* status masks to interrogate printer status */
173 #define RDY_MASK	(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)	/* ready ? */
174 #define LP_READY	(LPS_SEL|LPS_NBSY|LPS_NERR)
175 
176 /* Printer Ready condition  - from lpa.c */
177 /* Only used in polling code */
178 #define	LPS_INVERT	(LPS_NBSY | LPS_NACK |           LPS_SEL | LPS_NERR)
179 #define	LPS_MASK	(LPS_NBSY | LPS_NACK | LPS_OUT | LPS_SEL | LPS_NERR)
180 #define	NOT_READY(ppbus) ((ppb_rstr(ppbus)^LPS_INVERT)&LPS_MASK)
181 
182 #define	MAX_SLEEP	(hz*5)	/* Timeout while waiting for device ready */
183 #define	MAX_SPIN	20	/* Max delay for device ready in usecs */
184 
185 
186 static	d_open_t	lptopen;
187 static	d_close_t	lptclose;
188 static	d_write_t	lptwrite;
189 static	d_read_t	lptread;
190 static	d_ioctl_t	lptioctl;
191 
192 static struct cdevsw lpt_cdevsw = {
193 	.d_version =	D_VERSION,
194 	.d_flags =	D_NEEDGIANT,
195 	.d_open =	lptopen,
196 	.d_close =	lptclose,
197 	.d_read =	lptread,
198 	.d_write =	lptwrite,
199 	.d_ioctl =	lptioctl,
200 	.d_name =	LPT_NAME,
201 };
202 
203 static int
204 lpt_request_ppbus(device_t dev, int how)
205 {
206 	device_t ppbus = device_get_parent(dev);
207 	struct lpt_data *sc = DEVTOSOFTC(dev);
208 	int error;
209 
210 	if (sc->sc_state & HAVEBUS)
211 		return (0);
212 
213 	/* we have the bus only if the request succeded */
214 	if ((error = ppb_request_bus(ppbus, dev, how)) == 0)
215 		sc->sc_state |= HAVEBUS;
216 
217 	return (error);
218 }
219 
220 static int
221 lpt_release_ppbus(device_t dev)
222 {
223 	device_t ppbus = device_get_parent(dev);
224 	struct lpt_data *sc = DEVTOSOFTC(dev);
225 	int error = 0;
226 
227 	if ((error = ppb_release_bus(ppbus, dev)) == 0)
228 		sc->sc_state &= ~HAVEBUS;
229 
230 	return (error);
231 }
232 
233 /*
234  * Internal routine to lptprobe to do port tests of one byte value
235  */
236 static int
237 lpt_port_test(device_t ppbus, u_char data, u_char mask)
238 {
239 	int	temp, timeout;
240 
241 	data = data & mask;
242 	ppb_wdtr(ppbus, data);
243 	timeout = 10000;
244 	do {
245 		DELAY(10);
246 		temp = ppb_rdtr(ppbus) & mask;
247 	}
248 	while (temp != data && --timeout);
249 	lprintf(("out=%x\tin=%x\ttout=%d\n", data, temp, timeout));
250 	return (temp == data);
251 }
252 
253 /*
254  * Probe simplified by replacing multiple loops with a hardcoded
255  * test pattern - 1999/02/08 des@freebsd.org
256  *
257  * New lpt port probe Geoff Rehmet - Rhodes University - 14/2/94
258  * Based partially on Rod Grimes' printer probe
259  *
260  * Logic:
261  *	1) If no port address was given, use the bios detected ports
262  *	   and autodetect what ports the printers are on.
263  *	2) Otherwise, probe the data port at the address given,
264  *	   using the method in Rod Grimes' port probe.
265  *	   (Much code ripped off directly from Rod's probe.)
266  *
267  * Comments from Rod's probe:
268  * Logic:
269  *	1) You should be able to write to and read back the same value
270  *	   to the data port.  Do an alternating zeros, alternating ones,
271  *	   walking zero, and walking one test to check for stuck bits.
272  *
273  *	2) You should be able to write to and read back the same value
274  *	   to the control port lower 5 bits, the upper 3 bits are reserved
275  *	   per the IBM PC technical reference manauls and different boards
276  *	   do different things with them.  Do an alternating zeros, alternating
277  *	   ones, walking zero, and walking one test to check for stuck bits.
278  *
279  *	   Some printers drag the strobe line down when the are powered off
280  * 	   so this bit has been masked out of the control port test.
281  *
282  *	   XXX Some printers may not like a fast pulse on init or strobe, I
283  *	   don't know at this point, if that becomes a problem these bits
284  *	   should be turned off in the mask byte for the control port test.
285  *
286  *	   We are finally left with a mask of 0x14, due to some printers
287  *	   being adamant about holding other bits high ........
288  *
289  *	   Before probing the control port, we write a 0 to the data port -
290  *	   If not, some printers chuck out garbage when the strobe line
291  *	   gets toggled.
292  *
293  *	3) Set the data and control ports to a value of 0
294  *
295  *	This probe routine has been tested on Epson Lx-800, HP LJ3P,
296  *	Epson FX-1170 and C.Itoh 8510RM
297  *	printers.
298  *	Quick exit on fail added.
299  */
300 static int
301 lpt_detect(device_t dev)
302 {
303 	device_t ppbus = device_get_parent(dev);
304 
305 	static u_char	testbyte[18] = {
306 		0x55,			/* alternating zeros */
307 		0xaa,			/* alternating ones */
308 		0xfe, 0xfd, 0xfb, 0xf7,
309 		0xef, 0xdf, 0xbf, 0x7f,	/* walking zero */
310 		0x01, 0x02, 0x04, 0x08,
311 		0x10, 0x20, 0x40, 0x80	/* walking one */
312 	};
313 	int		i, error, status;
314 
315 	status = 1;				/* assume success */
316 
317 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
318 		printf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
319 		status = 0;
320 		goto end_probe;
321 	}
322 
323 	for (i = 0; i < 18 && status; i++)
324 		if (!lpt_port_test(ppbus, testbyte[i], 0xff)) {
325 			status = 0;
326 			goto end_probe;
327 		}
328 
329 end_probe:
330 	/* write 0's to control and data ports */
331 	ppb_wdtr(ppbus, 0);
332 	ppb_wctr(ppbus, 0);
333 
334 	lpt_release_ppbus(dev);
335 
336 	return (status);
337 }
338 
339 static void
340 lpt_identify(driver_t *driver, device_t parent)
341 {
342 
343 	device_t dev;
344 
345 	dev = device_find_child(parent, LPT_NAME, -1);
346 	if (!dev)
347 		BUS_ADD_CHILD(parent, 0, LPT_NAME, -1);
348 }
349 
350 /*
351  * lpt_probe()
352  */
353 static int
354 lpt_probe(device_t dev)
355 {
356 
357 	if (!lpt_detect(dev))
358 		return (ENXIO);
359 
360 	device_set_desc(dev, "Printer");
361 
362 	return (0);
363 }
364 
365 static int
366 lpt_attach(device_t dev)
367 {
368 	device_t ppbus = device_get_parent(dev);
369 	struct lpt_data *sc = DEVTOSOFTC(dev);
370 	int zero = 0, unit = device_get_unit(dev);
371 	int error;
372 	intptr_t irq;
373 
374 	sc->sc_primed = 0;	/* not primed yet */
375 
376 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
377 		printf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
378 		return (0);
379 	}
380 
381 	ppb_wctr(ppbus, LPC_NINIT);
382 
383 	/* check if we can use interrupt, should be done by ppc stuff */
384 	lprintf(("oldirq %x\n", sc->sc_irq));
385 
386 	/* retrieve the ppbus irq */
387 	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
388 
389 	if (irq > 0) {
390 		/* declare our interrupt handler */
391 		sc->intr_resource = bus_alloc_resource(dev, SYS_RES_IRQ,
392 						       &zero, irq, irq, 1, RF_SHAREABLE);
393 	}
394 	if (sc->intr_resource) {
395 		sc->sc_irq = LP_HAS_IRQ | LP_USE_IRQ | LP_ENABLE_IRQ;
396 		device_printf(dev, "Interrupt-driven port\n");
397 	} else {
398 		sc->sc_irq = 0;
399 		device_printf(dev, "Polled port\n");
400 	}
401 	lprintf(("irq %x %x\n", (int)irq, sc->sc_irq));
402 
403 	lpt_release_ppbus(dev);
404 
405 	make_dev(&lpt_cdevsw, unit,
406 	    UID_ROOT, GID_WHEEL, 0600, LPT_NAME "%d", unit);
407 	make_dev(&lpt_cdevsw, unit | LP_BYPASS,
408 	    UID_ROOT, GID_WHEEL, 0600, LPT_NAME "%d.ctl", unit);
409 	return (0);
410 }
411 
412 static int
413 lpt_detach(device_t dev)
414 {
415 	struct lpt_data *sc = DEVTOSOFTC(dev);
416 
417 	lpt_release_ppbus(dev);
418 	if (sc->intr_resource != 0) {
419 		BUS_TEARDOWN_INTR(device_get_parent(dev), dev,
420 		    sc->intr_resource, sc->intr_cookie);
421 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->intr_resource);
422 	}
423 
424 	return (0);
425 }
426 
427 static void
428 lptout(void *arg)
429 {
430 	device_t dev = (device_t)arg;
431 	struct lpt_data *sc = DEVTOSOFTC(dev);
432 #ifdef LPT_DEBUG
433 	device_t ppbus = device_get_parent(dev);
434 #endif
435 
436 	lprintf(("T %x ", ppb_rstr(ppbus)));
437 	if (sc->sc_state & OPEN) {
438 		sc->sc_backoff++;
439 		if (sc->sc_backoff > hz/LPTOUTMAX)
440 			sc->sc_backoff = sc->sc_backoff > hz/LPTOUTMAX;
441 		timeout(lptout, (caddr_t)dev, sc->sc_backoff);
442 	} else
443 		sc->sc_state &= ~TOUT;
444 
445 	if (sc->sc_state & EERROR)
446 		sc->sc_state &= ~EERROR;
447 
448 	/*
449 	 * Avoid possible hangs due to missed interrupts
450 	 */
451 	if (sc->sc_xfercnt) {
452 		lptintr(dev);
453 	} else {
454 		sc->sc_state &= ~OBUSY;
455 		wakeup(dev);
456 	}
457 }
458 
459 /*
460  * lptopen -- reset the printer, then wait until it's selected and not busy.
461  *	If LP_BYPASS flag is selected, then we do not try to select the
462  *	printer -- this is just used for passing ioctls.
463  */
464 
465 static	int
466 lptopen(struct cdev *dev, int flags, int fmt, struct thread *td)
467 {
468 	int s;
469 	int trys, err;
470 	u_int unit = LPTUNIT(minor(dev));
471 	struct lpt_data *sc = UNITOSOFTC(unit);
472 	device_t lptdev = UNITODEVICE(unit);
473 	device_t ppbus = device_get_parent(lptdev);
474 
475 	if (!sc)
476 		return (ENXIO);
477 
478 	if (sc->sc_state) {
479 		lprintf((LPT_NAME ": still open %x\n", sc->sc_state));
480 		return(EBUSY);
481 	} else
482 		sc->sc_state |= LPTINIT;
483 
484 	sc->sc_flags = LPTFLAGS(minor(dev));
485 
486 	/* Check for open with BYPASS flag set. */
487 	if (sc->sc_flags & LP_BYPASS) {
488 		sc->sc_state = OPEN;
489 		return(0);
490 	}
491 
492 	/* request the ppbus only if we don't have it already */
493 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0) {
494 		/* give it a chance to try later */
495 		sc->sc_state = 0;
496 		return (err);
497 	}
498 
499 	s = spltty();
500 	lprintf((LPT_NAME " flags 0x%x\n", sc->sc_flags));
501 
502 	/* set IRQ status according to ENABLE_IRQ flag
503 	 */
504 	if (sc->sc_irq & LP_ENABLE_IRQ)
505 		sc->sc_irq |= LP_USE_IRQ;
506 	else
507 		sc->sc_irq &= ~LP_USE_IRQ;
508 
509 	/* init printer */
510 	if ((sc->sc_flags & LP_NO_PRIME) == 0) {
511 		if((sc->sc_flags & LP_PRIMEOPEN) || sc->sc_primed == 0) {
512 			ppb_wctr(ppbus, 0);
513 			sc->sc_primed++;
514 			DELAY(500);
515 		}
516 	}
517 
518 	ppb_wctr(ppbus, LPC_SEL|LPC_NINIT);
519 
520 	/* wait till ready (printer running diagnostics) */
521 	trys = 0;
522 	do {
523 		/* ran out of waiting for the printer */
524 		if (trys++ >= LPINITRDY*4) {
525 			splx(s);
526 			sc->sc_state = 0;
527 			lprintf(("status %x\n", ppb_rstr(ppbus)));
528 
529 			lpt_release_ppbus(lptdev);
530 			return (EBUSY);
531 		}
532 
533 		/* wait 1/4 second, give up if we get a signal */
534 		if (tsleep(lptdev, LPPRI|PCATCH, "lptinit", hz/4) !=
535 		    EWOULDBLOCK) {
536 			sc->sc_state = 0;
537 			splx(s);
538 
539 			lpt_release_ppbus(lptdev);
540 			return (EBUSY);
541 		}
542 
543 		/* is printer online and ready for output */
544 	} while ((ppb_rstr(ppbus) &
545 			(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
546 					(LPS_SEL|LPS_NBSY|LPS_NERR));
547 
548 	sc->sc_control = LPC_SEL|LPC_NINIT;
549 	if (sc->sc_flags & LP_AUTOLF)
550 		sc->sc_control |= LPC_AUTOL;
551 
552 	/* enable interrupt if interrupt-driven */
553 	if (sc->sc_irq & LP_USE_IRQ)
554 		sc->sc_control |= LPC_ENA;
555 
556 	ppb_wctr(ppbus, sc->sc_control);
557 
558 	sc->sc_state = OPEN;
559 	sc->sc_inbuf = malloc(BUFSIZE, M_DEVBUF, M_WAITOK);
560 	sc->sc_statbuf = malloc(BUFSTATSIZE, M_DEVBUF, M_WAITOK);
561 	sc->sc_xfercnt = 0;
562 	splx(s);
563 
564 	/* release the ppbus */
565 	lpt_release_ppbus(lptdev);
566 
567 	/* only use timeout if using interrupt */
568 	lprintf(("irq %x\n", sc->sc_irq));
569 	if (sc->sc_irq & LP_USE_IRQ) {
570 		sc->sc_state |= TOUT;
571 		timeout(lptout, (caddr_t)lptdev,
572 			 (sc->sc_backoff = hz/LPTOUTINITIAL));
573 	}
574 
575 	lprintf(("opened.\n"));
576 	return(0);
577 }
578 
579 /*
580  * lptclose -- close the device, free the local line buffer.
581  *
582  * Check for interrupted write call added.
583  */
584 
585 static	int
586 lptclose(struct cdev *dev, int flags, int fmt, struct thread *td)
587 {
588 	u_int unit = LPTUNIT(minor(dev));
589 	struct lpt_data *sc = UNITOSOFTC(unit);
590 	device_t lptdev = UNITODEVICE(unit);
591         device_t ppbus = device_get_parent(lptdev);
592 	int err;
593 
594 	if(sc->sc_flags & LP_BYPASS)
595 		goto end_close;
596 
597 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
598 		return (err);
599 
600 	sc->sc_state &= ~OPEN;
601 
602 	/* if the last write was interrupted, don't complete it */
603 	if((!(sc->sc_state  & INTERRUPTED)) && (sc->sc_irq & LP_USE_IRQ))
604 		while ((ppb_rstr(ppbus) &
605 			(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
606 			(LPS_SEL|LPS_NBSY|LPS_NERR) || sc->sc_xfercnt)
607 			/* wait 1/4 second, give up if we get a signal */
608 			if (tsleep(lptdev, LPPRI|PCATCH,
609 				"lpclose", hz) != EWOULDBLOCK)
610 				break;
611 
612 	ppb_wctr(ppbus, LPC_NINIT);
613 	free(sc->sc_inbuf, M_DEVBUF);
614 	free(sc->sc_statbuf, M_DEVBUF);
615 
616 end_close:
617 	/* release the bus anyway
618 	 * unregistration of interrupt forced by release
619 	 */
620 	lpt_release_ppbus(lptdev);
621 
622 	sc->sc_state = 0;
623 	sc->sc_xfercnt = 0;
624 	lprintf(("closed.\n"));
625 	return(0);
626 }
627 
628 /*
629  * lpt_pushbytes()
630  *	Workhorse for actually spinning and writing bytes to printer
631  *	Derived from lpa.c
632  *	Originally by ?
633  *
634  *	This code is only used when we are polling the port
635  */
636 static int
637 lpt_pushbytes(device_t dev)
638 {
639 	struct lpt_data *sc = DEVTOSOFTC(dev);
640 	device_t ppbus = device_get_parent(dev);
641 	int spin, err, tic;
642 	char ch;
643 
644 	lprintf(("p"));
645 	/* loop for every character .. */
646 	while (sc->sc_xfercnt > 0) {
647 		/* printer data */
648 		ch = *(sc->sc_cp);
649 		sc->sc_cp++;
650 		sc->sc_xfercnt--;
651 
652 		/*
653 		 * Wait for printer ready.
654 		 * Loop 20 usecs testing BUSY bit, then sleep
655 		 * for exponentially increasing timeout. (vak)
656 		 */
657 		for (spin = 0; NOT_READY(ppbus) && spin < MAX_SPIN; ++spin)
658 			DELAY(1);	/* XXX delay is NOT this accurate! */
659 		if (spin >= MAX_SPIN) {
660 			tic = 0;
661 			while (NOT_READY(ppbus)) {
662 				/*
663 				 * Now sleep, every cycle a
664 				 * little longer ..
665 				 */
666 				tic = tic + tic + 1;
667 				/*
668 				 * But no more than 10 seconds. (vak)
669 				 */
670 				if (tic > MAX_SLEEP)
671 					tic = MAX_SLEEP;
672 				err = tsleep(dev, LPPRI,
673 					LPT_NAME "poll", tic);
674 				if (err != EWOULDBLOCK) {
675 					return (err);
676 				}
677 			}
678 		}
679 
680 		/* output data */
681 		ppb_wdtr(ppbus, ch);
682 		/* strobe */
683 		ppb_wctr(ppbus, sc->sc_control|LPC_STB);
684 		ppb_wctr(ppbus, sc->sc_control);
685 
686 	}
687 	return(0);
688 }
689 
690 /*
691  * lptread --retrieve printer status in IEEE1284 NIBBLE mode
692  */
693 
694 static int
695 lptread(struct cdev *dev, struct uio *uio, int ioflag)
696 {
697         u_int	unit = LPTUNIT(minor(dev));
698 	struct lpt_data *sc = UNITOSOFTC(unit);
699 	device_t lptdev = UNITODEVICE(unit);
700         device_t ppbus = device_get_parent(lptdev);
701 	int error = 0, len;
702 
703 	if (sc->sc_flags & LP_BYPASS) {
704 		/* we can't do reads in bypass mode */
705 		return (EPERM);
706 	}
707 
708 	if ((error = ppb_1284_negociate(ppbus, PPB_NIBBLE, 0)))
709 		return (error);
710 
711 	/* read data in an other buffer, read/write may be simultaneous */
712 	len = 0;
713 	while (uio->uio_resid) {
714 		if ((error = ppb_1284_read(ppbus, PPB_NIBBLE,
715 				sc->sc_statbuf, min(BUFSTATSIZE,
716 				uio->uio_resid), &len))) {
717 			goto error;
718 		}
719 
720 		if (!len)
721 			goto error;		/* no more data */
722 
723 		if ((error = uiomove(sc->sc_statbuf, len, uio)))
724 			goto error;
725 	}
726 
727 error:
728 	ppb_1284_terminate(ppbus);
729 	return (error);
730 }
731 
732 /*
733  * lptwrite --copy a line from user space to a local buffer, then call
734  * putc to get the chars moved to the output queue.
735  *
736  * Flagging of interrupted write added.
737  */
738 
739 static	int
740 lptwrite(struct cdev *dev, struct uio *uio, int ioflag)
741 {
742 	register unsigned n;
743 	int err;
744         u_int	unit = LPTUNIT(minor(dev));
745 	struct lpt_data *sc = UNITOSOFTC(unit);
746 	device_t lptdev = UNITODEVICE(unit);
747         device_t ppbus = device_get_parent(lptdev);
748 
749 	if(sc->sc_flags & LP_BYPASS) {
750 		/* we can't do writes in bypass mode */
751 		return(EPERM);
752 	}
753 
754 	/* request the ppbus only if we don't have it already */
755 	/* XXX interrupt registration?! */
756 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
757 		return (err);
758 
759 	/* if interrupts are working, register the handler */
760 	if (sc->sc_irq & LP_USE_IRQ) {
761 		/* register our interrupt handler */
762 		err = bus_setup_intr(lptdev, sc->intr_resource,
763 			       INTR_TYPE_TTY, NULL, lpt_intr, lptdev,
764 			       &sc->intr_cookie);
765 		if (err) {
766 			device_printf(lptdev, "handler registration failed, polled mode.\n");
767 			sc->sc_irq &= ~LP_USE_IRQ;
768 		}
769 	}
770 
771 	sc->sc_state &= ~INTERRUPTED;
772 	while ((n = min(BUFSIZE, uio->uio_resid)) != 0) {
773 		sc->sc_cp = sc->sc_inbuf;
774 		uiomove(sc->sc_cp, n, uio);
775 		sc->sc_xfercnt = n ;
776 
777 		if (sc->sc_irq & LP_ENABLE_EXT) {
778 			/* try any extended mode */
779 			err = ppb_write(ppbus, sc->sc_cp,
780 					sc->sc_xfercnt, 0);
781 			switch (err) {
782 			case 0:
783 				/* if not all data was sent, we could rely
784 				 * on polling for the last bytes */
785 				sc->sc_xfercnt = 0;
786 				break;
787 			case EINTR:
788 				sc->sc_state |= INTERRUPTED;
789 				return(err);
790 			case EINVAL:
791 				/* advanced mode not avail */
792 				log(LOG_NOTICE, LPT_NAME "%d: advanced mode not avail, polling\n", unit);
793 				break;
794 			default:
795 				return(err);
796 			}
797 		} else while ((sc->sc_xfercnt > 0)&&(sc->sc_irq & LP_USE_IRQ)) {
798 			lprintf(("i"));
799 			/* if the printer is ready for a char, */
800 			/* give it one */
801 			if ((sc->sc_state & OBUSY) == 0){
802 				lprintf(("\nC %d. ", sc->sc_xfercnt));
803 				lptintr(lptdev);
804 			}
805 			lprintf(("W "));
806 			if (sc->sc_state & OBUSY)
807 				if ((err = tsleep(lptdev,
808 					 LPPRI|PCATCH, LPT_NAME "write", 0))) {
809 					sc->sc_state |= INTERRUPTED;
810 					return(err);
811 				}
812 		}
813 
814 		/* check to see if we must do a polled write */
815 		if(!(sc->sc_irq & LP_USE_IRQ) && (sc->sc_xfercnt)) {
816 			lprintf(("p"));
817 
818 			err = lpt_pushbytes(lptdev);
819 
820 			if (err)
821 				return(err);
822 		}
823 	}
824 
825 	/* we have not been interrupted, release the ppbus */
826 	lpt_release_ppbus(lptdev);
827 
828 	return(0);
829 }
830 
831 /*
832  * lpt_intr -- handle printer interrupts which occur when the printer is
833  * ready to accept another char.
834  *
835  * do checking for interrupted write call.
836  */
837 
838 static void
839 lpt_intr(void *arg)
840 {
841 	device_t lptdev = (device_t)arg;
842         device_t ppbus = device_get_parent(lptdev);
843 	struct lpt_data *sc = DEVTOSOFTC(lptdev);
844 	int sts = 0;
845 	int i;
846 
847 	/* we must own the bus to use it */
848 	if ((sc->sc_state & HAVEBUS) == 0)
849 		return;
850 
851 	/*
852 	 * Is printer online and ready for output?
853 	 *
854 	 * Avoid falling back to lptout() too quickly.  First spin-loop
855 	 * to see if the printer will become ready ``really soon now''.
856 	 */
857 	for (i = 0; i < 100 &&
858 	     ((sts=ppb_rstr(ppbus)) & RDY_MASK) != LP_READY; i++) ;
859 
860 	if ((sts & RDY_MASK) == LP_READY) {
861 		sc->sc_state = (sc->sc_state | OBUSY) & ~EERROR;
862 		sc->sc_backoff = hz/LPTOUTINITIAL;
863 
864 		if (sc->sc_xfercnt) {
865 			/* send char */
866 			/*lprintf(("%x ", *sc->sc_cp)); */
867 			ppb_wdtr(ppbus, *sc->sc_cp++) ;
868 			ppb_wctr(ppbus, sc->sc_control|LPC_STB);
869 			/* DELAY(X) */
870 			ppb_wctr(ppbus, sc->sc_control);
871 
872 			/* any more data for printer */
873 			if(--(sc->sc_xfercnt) > 0) return;
874 		}
875 
876 		/*
877 		 * No more data waiting for printer.
878 		 * Wakeup is not done if write call was not interrupted.
879 		 */
880 		sc->sc_state &= ~OBUSY;
881 
882 		if(!(sc->sc_state & INTERRUPTED))
883 			wakeup(lptdev);
884 		lprintf(("w "));
885 		return;
886 	} else	{	/* check for error */
887 		if(((sts & (LPS_NERR | LPS_OUT) ) != LPS_NERR) &&
888 				(sc->sc_state & OPEN))
889 			sc->sc_state |= EERROR;
890 		/* lptout() will jump in and try to restart. */
891 	}
892 	lprintf(("sts %x ", sts));
893 }
894 
895 static void
896 lptintr(device_t dev)
897 {
898 	/* call the interrupt at required spl level */
899 	int s = spltty();
900 
901 	lpt_intr(dev);
902 
903 	splx(s);
904 	return;
905 }
906 
907 static	int
908 lptioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
909 {
910 	int	error = 0;
911         u_int	unit = LPTUNIT(minor(dev));
912         struct	lpt_data *sc = UNITOSOFTC(unit);
913 	u_char	old_sc_irq;	/* old printer IRQ status */
914 
915 	switch (cmd) {
916 	case LPT_IRQ :
917 		if(sc->sc_irq & LP_HAS_IRQ) {
918 			/*
919 			 * NOTE:
920 			 * If the IRQ status is changed,
921 			 * this will only be visible on the
922 			 * next open.
923 			 *
924 			 * If interrupt status changes,
925 			 * this gets syslog'd.
926 			 */
927 			old_sc_irq = sc->sc_irq;
928 			switch(*(int*)data) {
929 			case 0:
930 				sc->sc_irq &= (~LP_ENABLE_IRQ);
931 				break;
932 			case 1:
933 				sc->sc_irq &= (~LP_ENABLE_EXT);
934 				sc->sc_irq |= LP_ENABLE_IRQ;
935 				break;
936 			case 2:
937 				/* classic irq based transfer and advanced
938 				 * modes are in conflict
939 				 */
940 				sc->sc_irq &= (~LP_ENABLE_IRQ);
941 				sc->sc_irq |= LP_ENABLE_EXT;
942 				break;
943 			case 3:
944 				sc->sc_irq &= (~LP_ENABLE_EXT);
945 				break;
946 			default:
947 				break;
948 			}
949 
950 			if (old_sc_irq != sc->sc_irq )
951 				log(LOG_NOTICE, LPT_NAME "%d: switched to %s %s mode\n",
952 					unit,
953 					(sc->sc_irq & LP_ENABLE_IRQ)?
954 					"interrupt-driven":"polled",
955 					(sc->sc_irq & LP_ENABLE_EXT)?
956 					"extended":"standard");
957 		} else /* polled port */
958 			error = EOPNOTSUPP;
959 		break;
960 	default:
961 		error = ENODEV;
962 	}
963 
964 	return(error);
965 }
966 
967 static device_method_t lpt_methods[] = {
968 	/* device interface */
969 	DEVMETHOD(device_identify,	lpt_identify),
970 	DEVMETHOD(device_probe,		lpt_probe),
971 	DEVMETHOD(device_attach,	lpt_attach),
972 	DEVMETHOD(device_detach,	lpt_detach),
973 
974 	{ 0, 0 }
975 };
976 
977 static driver_t lpt_driver = {
978 	LPT_NAME,
979 	lpt_methods,
980 	sizeof(struct lpt_data),
981 };
982 
983 DRIVER_MODULE(lpt, ppbus, lpt_driver, lpt_devclass, 0, 0);
984 MODULE_DEPEND(lpt, ppbus, 1, 1, 1);
985