xref: /freebsd/sys/dev/ppbus/lpt.c (revision 2a4a1db342263067035ce69a4017c645da63455d)
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  * $FreeBSD$
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/kernel.h>
72 #include <sys/uio.h>
73 #include <sys/syslog.h>
74 #include <sys/malloc.h>
75 
76 #include <machine/bus.h>
77 #include <machine/resource.h>
78 #include <sys/rman.h>
79 
80 #include <dev/ppbus/lptio.h>
81 #include <dev/ppbus/ppbconf.h>
82 #include <dev/ppbus/ppb_1284.h>
83 #include <dev/ppbus/lpt.h>
84 #include "ppbus_if.h"
85 #include <dev/ppbus/ppbio.h>
86 
87 #ifndef LPT_DEBUG
88 #define lprintf(args)
89 #else
90 #define lprintf(args)						\
91 		do {						\
92 			if (lptflag)				\
93 				printf args;			\
94 		} while (0)
95 static int volatile lptflag = 1;
96 #endif
97 
98 #define	LPINITRDY	4	/* wait up to 4 seconds for a ready */
99 #define	LPTOUTINITIAL	10	/* initial timeout to wait for ready 1/10 s */
100 #define	LPTOUTMAX	1	/* maximal timeout 1 s */
101 #define	LPPRI		(PZERO+8)
102 #define	BUFSIZE		1024
103 #define	BUFSTATSIZE	32
104 
105 #define	LPTUNIT(s)	((s)&0x03)
106 #define	LPTFLAGS(s)	((s)&0xfc)
107 
108 struct lpt_data {
109 
110 	short	sc_state;
111 	/* default case: negative prime, negative ack, handshake strobe,
112 	   prime once */
113 	u_char	sc_control;
114 	char	sc_flags;
115 #define LP_POS_INIT	0x04	/* if we are a postive init signal */
116 #define LP_POS_ACK	0x08	/* if we are a positive going ack */
117 #define LP_NO_PRIME	0x10	/* don't prime the printer at all */
118 #define LP_PRIMEOPEN	0x20	/* prime on every open */
119 #define LP_AUTOLF	0x40	/* tell printer to do an automatic lf */
120 #define LP_BYPASS	0x80	/* bypass  printer ready checks */
121 	void	*sc_inbuf;
122 	void	*sc_statbuf;
123 	short	sc_xfercnt ;
124 	char	sc_primed;
125 	char	*sc_cp ;
126 	u_short	sc_irq ;	/* IRQ status of port */
127 #define LP_HAS_IRQ	0x01	/* we have an irq available */
128 #define LP_USE_IRQ	0x02	/* we are using our irq */
129 #define LP_ENABLE_IRQ	0x04	/* enable IRQ on open */
130 #define LP_ENABLE_EXT	0x10	/* we shall use advanced mode when possible */
131 	u_char	sc_backoff ;	/* time to call lptout() again */
132 
133 	struct resource *intr_resource;	/* interrupt resource */
134 	void *intr_cookie;		/* interrupt registration cookie */
135 
136 };
137 
138 #define LPT_NAME	"lpt"		/* our official name */
139 
140 static timeout_t lptout;
141 static int	lpt_port_test(device_t dev, u_char data, u_char mask);
142 static int	lpt_detect(device_t dev);
143 
144 #define DEVTOSOFTC(dev) \
145 	((struct lpt_data *)device_get_softc(dev))
146 #define UNITOSOFTC(unit) \
147 	((struct lpt_data *)devclass_get_softc(lpt_devclass, (unit)))
148 #define UNITODEVICE(unit) \
149 	(devclass_get_device(lpt_devclass, (unit)))
150 
151 static void lptintr(device_t dev);
152 static void lpt_intr(void *arg);	/* without spls */
153 
154 static devclass_t lpt_devclass;
155 
156 
157 /* bits for state */
158 #define	OPEN		(1<<0)	/* device is open */
159 #define	ASLP		(1<<1)	/* awaiting draining of printer */
160 #define	EERROR		(1<<2)	/* error was received from printer */
161 #define	OBUSY		(1<<3)	/* printer is busy doing output */
162 #define LPTOUT		(1<<4)	/* timeout while not selected */
163 #define TOUT		(1<<5)	/* timeout while not selected */
164 #define LPTINIT		(1<<6)	/* waiting to initialize for open */
165 #define INTERRUPTED	(1<<7)	/* write call was interrupted */
166 
167 #define HAVEBUS		(1<<8)	/* the driver owns the bus */
168 
169 
170 /* status masks to interrogate printer status */
171 #define RDY_MASK	(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)	/* ready ? */
172 #define LP_READY	(LPS_SEL|LPS_NBSY|LPS_NERR)
173 
174 /* Printer Ready condition  - from lpa.c */
175 /* Only used in polling code */
176 #define	LPS_INVERT	(LPS_NBSY | LPS_NACK |           LPS_SEL | LPS_NERR)
177 #define	LPS_MASK	(LPS_NBSY | LPS_NACK | LPS_OUT | LPS_SEL | LPS_NERR)
178 #define	NOT_READY(ppbus) ((ppb_rstr(ppbus)^LPS_INVERT)&LPS_MASK)
179 
180 #define	MAX_SLEEP	(hz*5)	/* Timeout while waiting for device ready */
181 #define	MAX_SPIN	20	/* Max delay for device ready in usecs */
182 
183 
184 static	d_open_t	lptopen;
185 static	d_close_t	lptclose;
186 static	d_write_t	lptwrite;
187 static	d_read_t	lptread;
188 static	d_ioctl_t	lptioctl;
189 
190 #define CDEV_MAJOR 16
191 static struct cdevsw lpt_cdevsw = {
192 	/* open */	lptopen,
193 	/* close */	lptclose,
194 	/* read */	lptread,
195 	/* write */	lptwrite,
196 	/* ioctl */	lptioctl,
197 	/* poll */	nopoll,
198 	/* mmap */	nommap,
199 	/* strategy */	nostrategy,
200 	/* name */	LPT_NAME,
201 	/* maj */	CDEV_MAJOR,
202 	/* dump */	nodump,
203 	/* psize */	nopsize,
204 	/* flags */	0,
205 };
206 
207 static int
208 lpt_request_ppbus(device_t dev, int how)
209 {
210 	device_t ppbus = device_get_parent(dev);
211 	struct lpt_data *sc = DEVTOSOFTC(dev);
212 	int error;
213 
214 	if (sc->sc_state & HAVEBUS)
215 		return (0);
216 
217 	/* we have the bus only if the request succeded */
218 	if ((error = ppb_request_bus(ppbus, dev, how)) == 0)
219 		sc->sc_state |= HAVEBUS;
220 
221 	return (error);
222 }
223 
224 static int
225 lpt_release_ppbus(device_t dev)
226 {
227 	device_t ppbus = device_get_parent(dev);
228 	struct lpt_data *sc = DEVTOSOFTC(dev);
229 	int error = 0;
230 
231 	if ((error = ppb_release_bus(ppbus, dev)) == 0)
232 		sc->sc_state &= ~HAVEBUS;
233 
234 	return (error);
235 }
236 
237 /*
238  * Internal routine to lptprobe to do port tests of one byte value
239  */
240 static int
241 lpt_port_test(device_t ppbus, u_char data, u_char mask)
242 {
243 	int	temp, timeout;
244 
245 	data = data & mask;
246 	ppb_wdtr(ppbus, data);
247 	timeout = 10000;
248 	do {
249 		DELAY(10);
250 		temp = ppb_rdtr(ppbus) & mask;
251 	}
252 	while (temp != data && --timeout);
253 	lprintf(("out=%x\tin=%x\ttout=%d\n", data, temp, timeout));
254 	return (temp == data);
255 }
256 
257 /*
258  * Probe simplified by replacing multiple loops with a hardcoded
259  * test pattern - 1999/02/08 des@freebsd.org
260  *
261  * New lpt port probe Geoff Rehmet - Rhodes University - 14/2/94
262  * Based partially on Rod Grimes' printer probe
263  *
264  * Logic:
265  *	1) If no port address was given, use the bios detected ports
266  *	   and autodetect what ports the printers are on.
267  *	2) Otherwise, probe the data port at the address given,
268  *	   using the method in Rod Grimes' port probe.
269  *	   (Much code ripped off directly from Rod's probe.)
270  *
271  * Comments from Rod's probe:
272  * Logic:
273  *	1) You should be able to write to and read back the same value
274  *	   to the data port.  Do an alternating zeros, alternating ones,
275  *	   walking zero, and walking one test to check for stuck bits.
276  *
277  *	2) You should be able to write to and read back the same value
278  *	   to the control port lower 5 bits, the upper 3 bits are reserved
279  *	   per the IBM PC technical reference manauls and different boards
280  *	   do different things with them.  Do an alternating zeros, alternating
281  *	   ones, walking zero, and walking one test to check for stuck bits.
282  *
283  *	   Some printers drag the strobe line down when the are powered off
284  * 	   so this bit has been masked out of the control port test.
285  *
286  *	   XXX Some printers may not like a fast pulse on init or strobe, I
287  *	   don't know at this point, if that becomes a problem these bits
288  *	   should be turned off in the mask byte for the control port test.
289  *
290  *	   We are finally left with a mask of 0x14, due to some printers
291  *	   being adamant about holding other bits high ........
292  *
293  *	   Before probing the control port, we write a 0 to the data port -
294  *	   If not, some printers chuck out garbage when the strobe line
295  *	   gets toggled.
296  *
297  *	3) Set the data and control ports to a value of 0
298  *
299  *	This probe routine has been tested on Epson Lx-800, HP LJ3P,
300  *	Epson FX-1170 and C.Itoh 8510RM
301  *	printers.
302  *	Quick exit on fail added.
303  */
304 static int
305 lpt_detect(device_t dev)
306 {
307 	device_t ppbus = device_get_parent(dev);
308 
309 	static u_char	testbyte[18] = {
310 		0x55,			/* alternating zeros */
311 		0xaa,			/* alternating ones */
312 		0xfe, 0xfd, 0xfb, 0xf7,
313 		0xef, 0xdf, 0xbf, 0x7f,	/* walking zero */
314 		0x01, 0x02, 0x04, 0x08,
315 		0x10, 0x20, 0x40, 0x80	/* walking one */
316 	};
317 	int		i, error, status;
318 
319 	status = 1;				/* assume success */
320 
321 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
322 		printf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
323 		status = 0;
324 		goto end_probe;
325 	}
326 
327 	for (i = 0; i < 18 && status; i++)
328 		if (!lpt_port_test(ppbus, testbyte[i], 0xff)) {
329 			status = 0;
330 			goto end_probe;
331 		}
332 
333 end_probe:
334 	/* write 0's to control and data ports */
335 	ppb_wdtr(ppbus, 0);
336 	ppb_wctr(ppbus, 0);
337 
338 	lpt_release_ppbus(dev);
339 
340 	return (status);
341 }
342 
343 static void
344 lpt_identify(driver_t *driver, device_t parent)
345 {
346 
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 	struct lpt_data *sc;
357 
358 	sc = DEVTOSOFTC(dev);
359 	bzero(sc, sizeof(struct lpt_data));
360 
361 	/*
362 	 * Now, try to detect the printer.
363 	 */
364 	if (!lpt_detect(dev))
365 		return (ENXIO);
366 
367 	device_set_desc(dev, "Printer");
368 
369 	return (0);
370 }
371 
372 static int
373 lpt_attach(device_t dev)
374 {
375 	device_t ppbus = device_get_parent(dev);
376 	struct lpt_data *sc = DEVTOSOFTC(dev);
377 	int zero = 0, unit = device_get_unit(dev);
378 	int error;
379 	uintptr_t irq;
380 
381 	sc->sc_primed = 0;	/* not primed yet */
382 
383 	if ((error = lpt_request_ppbus(dev, PPB_DONTWAIT))) {
384 		printf(LPT_NAME ": cannot alloc ppbus (%d)!\n", error);
385 		return (0);
386 	}
387 
388 	ppb_wctr(ppbus, LPC_NINIT);
389 
390 	/* check if we can use interrupt, should be done by ppc stuff */
391 	lprintf(("oldirq %x\n", sc->sc_irq));
392 
393 	/* retrieve the ppbus irq */
394 	BUS_READ_IVAR(ppbus, dev, PPBUS_IVAR_IRQ, &irq);
395 
396 	if (irq > 0) {
397 		/* declare our interrupt handler */
398 		sc->intr_resource = bus_alloc_resource(dev, SYS_RES_IRQ,
399 						       &zero, irq, irq, 1, RF_SHAREABLE);
400 	}
401 	if (sc->intr_resource) {
402 		sc->sc_irq = LP_HAS_IRQ | LP_USE_IRQ | LP_ENABLE_IRQ;
403 		device_printf(dev, "Interrupt-driven port\n");
404 	} else {
405 		sc->sc_irq = 0;
406 		device_printf(dev, "Polled port\n");
407 	}
408 	lprintf(("irq %x %x\n", irq, sc->sc_irq));
409 
410 	lpt_release_ppbus(dev);
411 
412 	make_dev(&lpt_cdevsw, unit,
413 	    UID_ROOT, GID_WHEEL, 0600, LPT_NAME "%d", unit);
414 	make_dev(&lpt_cdevsw, unit | LP_BYPASS,
415 	    UID_ROOT, GID_WHEEL, 0600, LPT_NAME "%d.ctl", unit);
416 	return (0);
417 }
418 
419 static void
420 lptout(void *arg)
421 {
422 	device_t dev = (device_t)arg;
423 	struct lpt_data *sc = DEVTOSOFTC(dev);
424 #ifdef LPT_DEBUG
425 	device_t ppbus = device_get_parent(dev);
426 #endif
427 
428 	lprintf(("T %x ", ppb_rstr(ppbus)));
429 	if (sc->sc_state & OPEN) {
430 		sc->sc_backoff++;
431 		if (sc->sc_backoff > hz/LPTOUTMAX)
432 			sc->sc_backoff = sc->sc_backoff > hz/LPTOUTMAX;
433 		timeout(lptout, (caddr_t)dev, sc->sc_backoff);
434 	} else
435 		sc->sc_state &= ~TOUT;
436 
437 	if (sc->sc_state & EERROR)
438 		sc->sc_state &= ~EERROR;
439 
440 	/*
441 	 * Avoid possible hangs due to missed interrupts
442 	 */
443 	if (sc->sc_xfercnt) {
444 		lptintr(dev);
445 	} else {
446 		sc->sc_state &= ~OBUSY;
447 		wakeup((caddr_t)dev);
448 	}
449 }
450 
451 /*
452  * lptopen -- reset the printer, then wait until it's selected and not busy.
453  *	If LP_BYPASS flag is selected, then we do not try to select the
454  *	printer -- this is just used for passing ioctls.
455  */
456 
457 static	int
458 lptopen(dev_t dev, int flags, int fmt, struct thread *td)
459 {
460 	int s;
461 	int trys, err;
462 	u_int unit = LPTUNIT(minor(dev));
463 	struct lpt_data *sc = UNITOSOFTC(unit);
464 	device_t lptdev = UNITODEVICE(unit);
465 	device_t ppbus = device_get_parent(lptdev);
466 
467 	if (!sc)
468 		return (ENXIO);
469 
470 	if (sc->sc_state) {
471 		lprintf((LPT_NAME ": still open %x\n", sc->sc_state));
472 		return(EBUSY);
473 	} else
474 		sc->sc_state |= LPTINIT;
475 
476 	sc->sc_flags = LPTFLAGS(minor(dev));
477 
478 	/* Check for open with BYPASS flag set. */
479 	if (sc->sc_flags & LP_BYPASS) {
480 		sc->sc_state = OPEN;
481 		return(0);
482 	}
483 
484 	/* request the ppbus only if we don't have it already */
485 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0) {
486 		/* give it a chance to try later */
487 		sc->sc_state = 0;
488 		return (err);
489 	}
490 
491 	s = spltty();
492 	lprintf((LPT_NAME " flags 0x%x\n", sc->sc_flags));
493 
494 	/* set IRQ status according to ENABLE_IRQ flag
495 	 */
496 	if (sc->sc_irq & LP_ENABLE_IRQ)
497 		sc->sc_irq |= LP_USE_IRQ;
498 	else
499 		sc->sc_irq &= ~LP_USE_IRQ;
500 
501 	/* init printer */
502 	if ((sc->sc_flags & LP_NO_PRIME) == 0) {
503 		if((sc->sc_flags & LP_PRIMEOPEN) || sc->sc_primed == 0) {
504 			ppb_wctr(ppbus, 0);
505 			sc->sc_primed++;
506 			DELAY(500);
507 		}
508 	}
509 
510 	ppb_wctr(ppbus, LPC_SEL|LPC_NINIT);
511 
512 	/* wait till ready (printer running diagnostics) */
513 	trys = 0;
514 	do {
515 		/* ran out of waiting for the printer */
516 		if (trys++ >= LPINITRDY*4) {
517 			splx(s);
518 			sc->sc_state = 0;
519 			lprintf(("status %x\n", ppb_rstr(ppbus)));
520 
521 			lpt_release_ppbus(lptdev);
522 			return (EBUSY);
523 		}
524 
525 		/* wait 1/4 second, give up if we get a signal */
526 		if (tsleep((caddr_t)lptdev, LPPRI|PCATCH, "lptinit", hz/4) !=
527 		    EWOULDBLOCK) {
528 			sc->sc_state = 0;
529 			splx(s);
530 
531 			lpt_release_ppbus(lptdev);
532 			return (EBUSY);
533 		}
534 
535 		/* is printer online and ready for output */
536 	} while ((ppb_rstr(ppbus) &
537 			(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
538 					(LPS_SEL|LPS_NBSY|LPS_NERR));
539 
540 	sc->sc_control = LPC_SEL|LPC_NINIT;
541 	if (sc->sc_flags & LP_AUTOLF)
542 		sc->sc_control |= LPC_AUTOL;
543 
544 	/* enable interrupt if interrupt-driven */
545 	if (sc->sc_irq & LP_USE_IRQ)
546 		sc->sc_control |= LPC_ENA;
547 
548 	ppb_wctr(ppbus, sc->sc_control);
549 
550 	sc->sc_state = OPEN;
551 	sc->sc_inbuf = malloc(BUFSIZE, M_DEVBUF, M_WAITOK);
552 	sc->sc_statbuf = malloc(BUFSTATSIZE, M_DEVBUF, M_WAITOK);
553 	sc->sc_xfercnt = 0;
554 	splx(s);
555 
556 	/* release the ppbus */
557 	lpt_release_ppbus(lptdev);
558 
559 	/* only use timeout if using interrupt */
560 	lprintf(("irq %x\n", sc->sc_irq));
561 	if (sc->sc_irq & LP_USE_IRQ) {
562 		sc->sc_state |= TOUT;
563 		timeout(lptout, (caddr_t)lptdev,
564 			 (sc->sc_backoff = hz/LPTOUTINITIAL));
565 	}
566 
567 	lprintf(("opened.\n"));
568 	return(0);
569 }
570 
571 /*
572  * lptclose -- close the device, free the local line buffer.
573  *
574  * Check for interrupted write call added.
575  */
576 
577 static	int
578 lptclose(dev_t dev, int flags, int fmt, struct thread *td)
579 {
580 	u_int unit = LPTUNIT(minor(dev));
581 	struct lpt_data *sc = UNITOSOFTC(unit);
582 	device_t lptdev = UNITODEVICE(unit);
583         device_t ppbus = device_get_parent(lptdev);
584 	int err;
585 
586 	if(sc->sc_flags & LP_BYPASS)
587 		goto end_close;
588 
589 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
590 		return (err);
591 
592 	sc->sc_state &= ~OPEN;
593 
594 	/* if the last write was interrupted, don't complete it */
595 	if((!(sc->sc_state  & INTERRUPTED)) && (sc->sc_irq & LP_USE_IRQ))
596 		while ((ppb_rstr(ppbus) &
597 			(LPS_SEL|LPS_OUT|LPS_NBSY|LPS_NERR)) !=
598 			(LPS_SEL|LPS_NBSY|LPS_NERR) || sc->sc_xfercnt)
599 			/* wait 1/4 second, give up if we get a signal */
600 			if (tsleep((caddr_t)lptdev, LPPRI|PCATCH,
601 				"lpclose", hz) != EWOULDBLOCK)
602 				break;
603 
604 	ppb_wctr(ppbus, LPC_NINIT);
605 	free(sc->sc_inbuf, M_DEVBUF);
606 	free(sc->sc_statbuf, M_DEVBUF);
607 
608 end_close:
609 	/* release the bus anyway
610 	 * unregistration of interrupt forced by release
611 	 */
612 	lpt_release_ppbus(lptdev);
613 
614 	sc->sc_state = 0;
615 	sc->sc_xfercnt = 0;
616 	lprintf(("closed.\n"));
617 	return(0);
618 }
619 
620 /*
621  * lpt_pushbytes()
622  *	Workhorse for actually spinning and writing bytes to printer
623  *	Derived from lpa.c
624  *	Originally by ?
625  *
626  *	This code is only used when we are polling the port
627  */
628 static int
629 lpt_pushbytes(device_t dev)
630 {
631 	struct lpt_data *sc = DEVTOSOFTC(dev);
632 	device_t ppbus = device_get_parent(dev);
633 	int spin, err, tic;
634 	char ch;
635 
636 	lprintf(("p"));
637 	/* loop for every character .. */
638 	while (sc->sc_xfercnt > 0) {
639 		/* printer data */
640 		ch = *(sc->sc_cp);
641 		sc->sc_cp++;
642 		sc->sc_xfercnt--;
643 
644 		/*
645 		 * Wait for printer ready.
646 		 * Loop 20 usecs testing BUSY bit, then sleep
647 		 * for exponentially increasing timeout. (vak)
648 		 */
649 		for (spin = 0; NOT_READY(ppbus) && spin < MAX_SPIN; ++spin)
650 			DELAY(1);	/* XXX delay is NOT this accurate! */
651 		if (spin >= MAX_SPIN) {
652 			tic = 0;
653 			while (NOT_READY(ppbus)) {
654 				/*
655 				 * Now sleep, every cycle a
656 				 * little longer ..
657 				 */
658 				tic = tic + tic + 1;
659 				/*
660 				 * But no more than 10 seconds. (vak)
661 				 */
662 				if (tic > MAX_SLEEP)
663 					tic = MAX_SLEEP;
664 				err = tsleep((caddr_t)dev, LPPRI,
665 					LPT_NAME "poll", tic);
666 				if (err != EWOULDBLOCK) {
667 					return (err);
668 				}
669 			}
670 		}
671 
672 		/* output data */
673 		ppb_wdtr(ppbus, ch);
674 		/* strobe */
675 		ppb_wctr(ppbus, sc->sc_control|LPC_STB);
676 		ppb_wctr(ppbus, sc->sc_control);
677 
678 	}
679 	return(0);
680 }
681 
682 /*
683  * lptread --retrieve printer status in IEEE1284 NIBBLE mode
684  */
685 
686 static int
687 lptread(dev_t dev, struct uio *uio, int ioflag)
688 {
689         u_int	unit = LPTUNIT(minor(dev));
690 	struct lpt_data *sc = UNITOSOFTC(unit);
691 	device_t lptdev = UNITODEVICE(unit);
692         device_t ppbus = device_get_parent(lptdev);
693 	int error = 0, len;
694 
695 	if (sc->sc_flags & LP_BYPASS) {
696 		/* we can't do reads in bypass mode */
697 		return (EPERM);
698 	}
699 
700 	if ((error = ppb_1284_negociate(ppbus, PPB_NIBBLE, 0)))
701 		return (error);
702 
703 	/* read data in an other buffer, read/write may be simultaneous */
704 	len = 0;
705 	while (uio->uio_resid) {
706 		if ((error = ppb_1284_read(ppbus, PPB_NIBBLE,
707 				sc->sc_statbuf, min(BUFSTATSIZE,
708 				uio->uio_resid), &len))) {
709 			goto error;
710 		}
711 
712 		if (!len)
713 			goto error;		/* no more data */
714 
715 		if ((error = uiomove(sc->sc_statbuf, len, uio)))
716 			goto error;
717 	}
718 
719 error:
720 	ppb_1284_terminate(ppbus);
721 	return (error);
722 }
723 
724 /*
725  * lptwrite --copy a line from user space to a local buffer, then call
726  * putc to get the chars moved to the output queue.
727  *
728  * Flagging of interrupted write added.
729  */
730 
731 static	int
732 lptwrite(dev_t dev, struct uio *uio, int ioflag)
733 {
734 	register unsigned n;
735 	int err;
736         u_int	unit = LPTUNIT(minor(dev));
737 	struct lpt_data *sc = UNITOSOFTC(unit);
738 	device_t lptdev = UNITODEVICE(unit);
739         device_t ppbus = device_get_parent(lptdev);
740 
741 	if(sc->sc_flags & LP_BYPASS) {
742 		/* we can't do writes in bypass mode */
743 		return(EPERM);
744 	}
745 
746 	/* request the ppbus only if we don't have it already */
747 	/* XXX interrupt registration?! */
748 	if ((err = lpt_request_ppbus(lptdev, PPB_WAIT|PPB_INTR)) != 0)
749 		return (err);
750 
751 	/* if interrupts are working, register the handler */
752 	if (sc->sc_irq & LP_USE_IRQ) {
753 		/* register our interrupt handler */
754 		err = BUS_SETUP_INTR(ppbus, lptdev, sc->intr_resource,
755 			       INTR_TYPE_TTY, lpt_intr, lptdev,
756 			       &sc->intr_cookie);
757 		if (err) {
758 			device_printf(lptdev, "handler registration failed, polled mode.\n");
759 			sc->sc_irq &= ~LP_USE_IRQ;
760 		}
761 	}
762 
763 	sc->sc_state &= ~INTERRUPTED;
764 	while ((n = min(BUFSIZE, uio->uio_resid)) != 0) {
765 		sc->sc_cp = sc->sc_inbuf;
766 		uiomove(sc->sc_cp, n, uio);
767 		sc->sc_xfercnt = n ;
768 
769 		if (sc->sc_irq & LP_ENABLE_EXT) {
770 			/* try any extended mode */
771 			err = ppb_write(ppbus, sc->sc_cp,
772 					sc->sc_xfercnt, 0);
773 			switch (err) {
774 			case 0:
775 				/* if not all data was sent, we could rely
776 				 * on polling for the last bytes */
777 				sc->sc_xfercnt = 0;
778 				break;
779 			case EINTR:
780 				sc->sc_state |= INTERRUPTED;
781 				return(err);
782 			case EINVAL:
783 				/* advanced mode not avail */
784 				log(LOG_NOTICE, LPT_NAME "%d: advanced mode not avail, polling\n", unit);
785 				break;
786 			default:
787 				return(err);
788 			}
789 		} else while ((sc->sc_xfercnt > 0)&&(sc->sc_irq & LP_USE_IRQ)) {
790 			lprintf(("i"));
791 			/* if the printer is ready for a char, */
792 			/* give it one */
793 			if ((sc->sc_state & OBUSY) == 0){
794 				lprintf(("\nC %d. ", sc->sc_xfercnt));
795 				lptintr(lptdev);
796 			}
797 			lprintf(("W "));
798 			if (sc->sc_state & OBUSY)
799 				if ((err = tsleep((caddr_t)lptdev,
800 					 LPPRI|PCATCH, LPT_NAME "write", 0))) {
801 					sc->sc_state |= INTERRUPTED;
802 					return(err);
803 				}
804 		}
805 
806 		/* check to see if we must do a polled write */
807 		if(!(sc->sc_irq & LP_USE_IRQ) && (sc->sc_xfercnt)) {
808 			lprintf(("p"));
809 
810 			err = lpt_pushbytes(lptdev);
811 
812 			if (err)
813 				return(err);
814 		}
815 	}
816 
817 	/* we have not been interrupted, release the ppbus */
818 	lpt_release_ppbus(lptdev);
819 
820 	return(0);
821 }
822 
823 /*
824  * lpt_intr -- handle printer interrupts which occur when the printer is
825  * ready to accept another char.
826  *
827  * do checking for interrupted write call.
828  */
829 
830 static void
831 lpt_intr(void *arg)
832 {
833 	device_t lptdev = (device_t)arg;
834         device_t ppbus = device_get_parent(lptdev);
835 	struct lpt_data *sc = DEVTOSOFTC(lptdev);
836 	int sts = 0;
837 	int i;
838 
839 	/* we must own the bus to use it */
840 	if ((sc->sc_state & HAVEBUS) == 0)
841 		return;
842 
843 	/*
844 	 * Is printer online and ready for output?
845 	 *
846 	 * Avoid falling back to lptout() too quickly.  First spin-loop
847 	 * to see if the printer will become ready ``really soon now''.
848 	 */
849 	for (i = 0; i < 100 &&
850 	     ((sts=ppb_rstr(ppbus)) & RDY_MASK) != LP_READY; i++) ;
851 
852 	if ((sts & RDY_MASK) == LP_READY) {
853 		sc->sc_state = (sc->sc_state | OBUSY) & ~EERROR;
854 		sc->sc_backoff = hz/LPTOUTINITIAL;
855 
856 		if (sc->sc_xfercnt) {
857 			/* send char */
858 			/*lprintf(("%x ", *sc->sc_cp)); */
859 			ppb_wdtr(ppbus, *sc->sc_cp++) ;
860 			ppb_wctr(ppbus, sc->sc_control|LPC_STB);
861 			/* DELAY(X) */
862 			ppb_wctr(ppbus, sc->sc_control);
863 
864 			/* any more data for printer */
865 			if(--(sc->sc_xfercnt) > 0) return;
866 		}
867 
868 		/*
869 		 * No more data waiting for printer.
870 		 * Wakeup is not done if write call was not interrupted.
871 		 */
872 		sc->sc_state &= ~OBUSY;
873 
874 		if(!(sc->sc_state & INTERRUPTED))
875 			wakeup((caddr_t)lptdev);
876 		lprintf(("w "));
877 		return;
878 	} else	{	/* check for error */
879 		if(((sts & (LPS_NERR | LPS_OUT) ) != LPS_NERR) &&
880 				(sc->sc_state & OPEN))
881 			sc->sc_state |= EERROR;
882 		/* lptout() will jump in and try to restart. */
883 	}
884 	lprintf(("sts %x ", sts));
885 }
886 
887 static void
888 lptintr(device_t dev)
889 {
890 	/* call the interrupt at required spl level */
891 	int s = spltty();
892 
893 	lpt_intr(dev);
894 
895 	splx(s);
896 	return;
897 }
898 
899 static	int
900 lptioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
901 {
902 	int	error = 0;
903         u_int	unit = LPTUNIT(minor(dev));
904         struct	lpt_data *sc = UNITOSOFTC(unit);
905 	u_char	old_sc_irq;	/* old printer IRQ status */
906 
907 	switch (cmd) {
908 	case LPT_IRQ :
909 		if(sc->sc_irq & LP_HAS_IRQ) {
910 			/*
911 			 * NOTE:
912 			 * If the IRQ status is changed,
913 			 * this will only be visible on the
914 			 * next open.
915 			 *
916 			 * If interrupt status changes,
917 			 * this gets syslog'd.
918 			 */
919 			old_sc_irq = sc->sc_irq;
920 			switch(*(int*)data) {
921 			case 0:
922 				sc->sc_irq &= (~LP_ENABLE_IRQ);
923 				break;
924 			case 1:
925 				sc->sc_irq &= (~LP_ENABLE_EXT);
926 				sc->sc_irq |= LP_ENABLE_IRQ;
927 				break;
928 			case 2:
929 				/* classic irq based transfer and advanced
930 				 * modes are in conflict
931 				 */
932 				sc->sc_irq &= (~LP_ENABLE_IRQ);
933 				sc->sc_irq |= LP_ENABLE_EXT;
934 				break;
935 			case 3:
936 				sc->sc_irq &= (~LP_ENABLE_EXT);
937 				break;
938 			default:
939 				break;
940 			}
941 
942 			if (old_sc_irq != sc->sc_irq )
943 				log(LOG_NOTICE, LPT_NAME "%d: switched to %s %s mode\n",
944 					unit,
945 					(sc->sc_irq & LP_ENABLE_IRQ)?
946 					"interrupt-driven":"polled",
947 					(sc->sc_irq & LP_ENABLE_EXT)?
948 					"extended":"standard");
949 		} else /* polled port */
950 			error = EOPNOTSUPP;
951 		break;
952 	default:
953 		error = ENODEV;
954 	}
955 
956 	return(error);
957 }
958 
959 static device_method_t lpt_methods[] = {
960 	/* device interface */
961 	DEVMETHOD(device_identify,	lpt_identify),
962 	DEVMETHOD(device_probe,		lpt_probe),
963 	DEVMETHOD(device_attach,	lpt_attach),
964 
965 	{ 0, 0 }
966 };
967 
968 static driver_t lpt_driver = {
969 	LPT_NAME,
970 	lpt_methods,
971 	sizeof(struct lpt_data),
972 };
973 
974 DRIVER_MODULE(lpt, ppbus, lpt_driver, lpt_devclass, 0, 0);
975