xref: /netbsd/sys/dev/ic/cy.c (revision bf9ec67e)
1 /*	$NetBSD: cy.c,v 1.26 2002/03/17 19:40:57 atatat Exp $	*/
2 
3 /*
4  * cy.c
5  *
6  * Driver for Cyclades Cyclom-8/16/32 multiport serial cards
7  * (currently not tested with Cyclom-32 cards)
8  *
9  * Timo Rossi, 1996
10  *
11  * Supports both ISA and PCI Cyclom cards
12  *
13  * Lots of debug output can be enabled by defining CY_DEBUG
14  * Some debugging counters (number of receive/transmit interrupts etc.)
15  * can be enabled by defining CY_DEBUG1
16  */
17 
18 #include <sys/cdefs.h>
19 __KERNEL_RCSID(0, "$NetBSD: cy.c,v 1.26 2002/03/17 19:40:57 atatat Exp $");
20 
21 #include <sys/param.h>
22 #include <sys/ioctl.h>
23 #include <sys/syslog.h>
24 #include <sys/fcntl.h>
25 #include <sys/tty.h>
26 #include <sys/proc.h>
27 #include <sys/conf.h>
28 #include <sys/user.h>
29 #include <sys/ioctl.h>
30 #include <sys/select.h>
31 #include <sys/device.h>
32 #include <sys/malloc.h>
33 #include <sys/systm.h>
34 #include <sys/callout.h>
35 
36 #include <machine/bus.h>
37 
38 #include <dev/ic/cd1400reg.h>
39 #include <dev/ic/cyreg.h>
40 #include <dev/ic/cyvar.h>
41 
42 /* Macros to clear/set/test flags. */
43 #define	SET(t, f)	(t) |= (f)
44 #define	CLR(t, f)	(t) &= ~(f)
45 #define	ISSET(t, f)	((t) & (f))
46 
47 int	cyparam(struct tty *, struct termios *);
48 void	cystart(struct tty *);
49 void	cy_poll(void *);
50 int	cy_modem_control(struct cy_softc *, struct cy_port *, int, int);
51 void	cy_enable_transmitter(struct cy_softc *, struct cy_port *);
52 void	cd1400_channel_cmd(struct cy_softc *, struct cy_port *, int);
53 int	cy_speed(speed_t, int *, int *, int);
54 
55 extern struct cfdriver cy_cd;
56 
57 static int      cy_open = 0;
58 static int      cy_events = 0;
59 
60 int	cy_attached_ttys;
61 
62 cdev_decl(cy);
63 
64 struct callout cy_poll_callout = CALLOUT_INITIALIZER;
65 
66 /*
67  * Common probe routine
68  */
69 int
70 cy_find(struct cy_softc *sc)
71 {
72 	int cy_chip, chip;
73 	u_char firmware_ver;
74 	bus_space_tag_t tag = sc->sc_memt;
75 	bus_space_handle_t bsh = sc->sc_bsh;
76 	int bustype = sc->sc_bustype;
77 
78 	/* Cyclom card hardware reset */
79 	bus_space_write_1(tag, bsh, CY16_RESET << bustype, 0);
80 	DELAY(500);		/* wait for reset to complete */
81 	bus_space_write_1(tag, bsh, CY_CLEAR_INTR << bustype, 0);
82 
83 #ifdef CY_DEBUG
84 	printf("cy: card reset done\n");
85 #endif
86 	sc->sc_nchips = 0;
87 
88 	for (cy_chip = 0, chip = 0; cy_chip < CY_MAX_CD1400s;
89 	    cy_chip++, chip += (CY_CD1400_MEMSPACING << bustype)) {
90 		int i;
91 
92 		/*
93 		 * the last 4 nchips are 'interleaved' with the first 4 on
94 		 * 32-port boards
95 		 */
96 		if (cy_chip == 4)
97 			chip -= (CY32_ADDR_FIX << bustype);
98 
99 #ifdef CY_DEBUG
100 		printf("%s probe chip %d offset 0x%x ... ",
101 		    sc->sc_dev.dv_xname, cy_chip, chip);
102 #endif
103 
104 		/* wait until the chip is ready for command */
105 		DELAY(1000);
106 		if (bus_space_read_1(tag, bsh, chip +
107 		    ((CD1400_CCR << 1) << bustype)) != 0) {
108 #ifdef CY_DEBUG
109 			printf("not ready for command\n");
110 #endif
111 			break;
112 		}
113 		/* clear the firmware version reg. */
114 		bus_space_write_1(tag, bsh, chip +
115 		    ((CD1400_GFRCR << 1) << bustype), 0);
116 
117 		/*
118 	         * On Cyclom-16 references to non-existent chip 4
119 	         * actually access chip 0 (address line 9 not decoded).
120 	         * Here we check if the clearing of chip 4 GFRCR actually
121 	         * cleared chip 0 GFRCR. In that case we have a 16 port card.
122 	         */
123 		if (cy_chip == 4 &&
124 		    bus_space_read_1(tag, bsh, /* off for chip 0 (0) + */
125 		       ((CD1400_GFRCR << 1) << bustype)) == 0)
126 			break;
127 
128 		/* reset the chip */
129 		bus_space_write_1(tag, bsh, chip +
130 		    ((CD1400_CCR << 1) << bustype),
131 		    CD1400_CCR_CMDRESET | CD1400_CCR_FULLRESET);
132 
133 		/* wait for the chip to initialize itself */
134 		for (i = 0; i < 200; i++) {
135 			DELAY(50);
136 			firmware_ver = bus_space_read_1(tag, bsh, chip +
137 			    ((CD1400_GFRCR << 1) << bustype));
138 			if ((firmware_ver & 0xf0) == 0x40) /* found a CD1400 */
139 				break;
140 		}
141 #ifdef CY_DEBUG
142 		printf("firmware version 0x%x\n", firmware_ver);
143 #endif
144 
145 		if ((firmware_ver & 0xf0) != 0x40)
146 			break;
147 
148 		/* firmware version OK, CD1400 found */
149 		sc->sc_nchips++;
150 	}
151 
152 	if (sc->sc_nchips == 0) {
153 #ifdef CY_DEBUG
154 		printf("no CD1400s found\n");
155 #endif
156 		return 0;
157 	}
158 #ifdef CY_DEBUG
159 	printf("found %d CD1400s\n", sc->sc_nchips);
160 #endif
161 
162 	return 1;
163 }
164 
165 void
166 cy_attach(struct cy_softc *sc)
167 {
168 	int port, cy_chip, num_chips, cdu, chip;
169 	int cy_clock;
170 
171 	num_chips = sc->sc_nchips;
172 	if (num_chips == 0)
173 		return;
174 
175 	memset(sc->sc_ports, 0, sizeof(sc->sc_ports));
176 
177 	port = 0;
178 	for (cy_chip = 0, chip = 0; cy_chip < num_chips; cy_chip++,
179 	    chip += (CY_CD1400_MEMSPACING << sc->sc_bustype)) {
180 
181 		if (cy_chip == 4)
182 			chip -= (CY32_ADDR_FIX << sc->sc_bustype);
183 
184 #ifdef CY_DEBUG
185 		printf("attach CD1400 #%d offset 0x%x\n", cy_chip, chip);
186 #endif
187 		sc->sc_cd1400_offs[cy_chip] = chip;
188 
189 		/*
190 		 * configure port 0 as serial port (should already be after
191 		 * reset)
192 		 */
193 		cd_write_reg(sc, cy_chip, CD1400_GCR, 0);
194 
195 		if (cd_read_reg(sc, cy_chip, CD1400_GFRCR) <= 0x46)
196 			cy_clock = CY_CLOCK;
197 		else
198 			cy_clock = CY_CLOCK_60;
199 
200 		/* set up a receive timeout period (1ms) */
201 		cd_write_reg(sc, cy_chip, CD1400_PPR,
202 		    (cy_clock / CD1400_PPR_PRESCALER / 1000) + 1);
203 
204 		for (cdu = 0; cdu < CD1400_NO_OF_CHANNELS; cdu++) {
205 			sc->sc_ports[port].cy_softc = sc;
206 			sc->sc_ports[port].cy_port_num = port;
207 			sc->sc_ports[port].cy_chip = cy_chip;
208 			sc->sc_ports[port].cy_clock = cy_clock;
209 
210 			/* should we initialize anything else here? */
211 			port++;
212 		} /* for(each port on one CD1400...) */
213 
214 	} /* for(each CD1400 on a card... ) */
215 
216 	sc->sc_nchannels = port;
217 
218 	printf("%s: %d channels (ttyCY%03d..ttyCY%03d)\n",
219 	    sc->sc_dev.dv_xname, sc->sc_nchannels, cy_attached_ttys,
220 	    cy_attached_ttys + (sc->sc_nchannels - 1));
221 
222 	cy_attached_ttys += sc->sc_nchannels;
223 
224 	/* ensure an edge for the next interrupt */
225 	bus_space_write_1(sc->sc_memt, sc->sc_bsh,
226 	    CY_CLEAR_INTR << sc->sc_bustype, 0);
227 }
228 
229 #define	CYDIALOUT_MASK		0x80000
230 #define	CY_DIALOUT(dev)		(minor(dev) & CYDIALOUT_MASK)
231 
232 #define	CY_PORT(dev)		cy_getport((dev))
233 #define	CY_BOARD(cy)		((cy)->cy_softc)
234 
235 static struct cy_port *
236 cy_getport(dev_t dev)
237 {
238 	int i, j, k, u = minor(dev) & ~CYDIALOUT_MASK;
239 	struct cy_softc *sc;
240 
241 	for (i = 0, j = 0; i < cy_cd.cd_ndevs; i++) {
242 		k = j;
243 		sc = device_lookup(&cy_cd, i);
244 		if (sc == NULL)
245 			continue;
246 		if (sc->sc_nchannels == 0)
247 			continue;
248 		j += sc->sc_nchannels;
249 		if (j > u)
250 			break;
251 	}
252 
253 	if (i == cy_cd.cd_ndevs)
254 		return (NULL);
255 	else
256 		return (&sc->sc_ports[u - k]);
257 }
258 
259 /*
260  * open routine. returns zero if successfull, else error code
261  */
262 int
263 cyopen(dev_t dev, int flag, int mode, struct proc *p)
264 {
265 	struct cy_softc *sc;
266 	struct cy_port *cy;
267 	struct tty *tp;
268 	int s, error;
269 
270 	cy = CY_PORT(dev);
271 	if (cy == NULL)
272 		return (ENXIO);
273 	sc = CY_BOARD(cy);
274 
275 	s = spltty();
276 	if (cy->cy_tty == NULL) {
277 		if ((cy->cy_tty = ttymalloc()) == NULL) {
278 			splx(s);
279 			printf("%s: port %d: can't allocate tty\n",
280 			    sc->sc_dev.dv_xname, cy->cy_port_num);
281 			return (ENOMEM);
282 		}
283 		tty_attach(cy->cy_tty);
284 	}
285 	splx(s);
286 
287 	tp = cy->cy_tty;
288 	tp->t_oproc = cystart;
289 	tp->t_param = cyparam;
290 	tp->t_dev = dev;
291 
292 	if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
293 		ttychars(tp);
294 		tp->t_iflag = TTYDEF_IFLAG;
295 		tp->t_oflag = TTYDEF_OFLAG;
296 		tp->t_cflag = TTYDEF_CFLAG;
297 		if (ISSET(cy->cy_openflags, TIOCFLAG_CLOCAL))
298 			SET(tp->t_cflag, CLOCAL);
299 		if (ISSET(cy->cy_openflags, TIOCFLAG_CRTSCTS))
300 			SET(tp->t_cflag, CRTSCTS);
301 		if (ISSET(cy->cy_openflags, TIOCFLAG_MDMBUF))
302 			SET(tp->t_cflag, MDMBUF);
303 		tp->t_lflag = TTYDEF_LFLAG;
304 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
305 
306 		s = spltty();
307 
308 		/*
309 		 * Allocate input ring buffer if we don't already have one
310 		 */
311 		if (cy->cy_ibuf == NULL) {
312 			cy->cy_ibuf = malloc(CY_IBUF_SIZE, M_DEVBUF, M_NOWAIT);
313 			if (cy->cy_ibuf == NULL) {
314 				printf("%s: port %d: can't allocate input buffer\n",
315 				       sc->sc_dev.dv_xname, cy->cy_port_num);
316 				splx(s);
317 				return ENOMEM;
318 			}
319 			cy->cy_ibuf_end = cy->cy_ibuf + CY_IBUF_SIZE;
320 		}
321 		/* mark the ring buffer as empty */
322 		cy->cy_ibuf_rd_ptr = cy->cy_ibuf_wr_ptr = cy->cy_ibuf;
323 
324 		/* select CD1400 channel */
325 		cd_write_reg(sc, cy->cy_chip, CD1400_CAR,
326 		    cy->cy_port_num & CD1400_CAR_CHAN);
327 		/* reset the channel */
328 		cd1400_channel_cmd(sc, cy, CD1400_CCR_CMDRESET);
329 		/* encode unit (port) number in LIVR */
330 		/* there is just enough space for 5 bits (32 ports) */
331 		cd_write_reg(sc, cy->cy_chip, CD1400_LIVR,
332 		    cy->cy_port_num << 3);
333 
334 		cy->cy_channel_control = 0;
335 
336 		/* hmm... need spltty() here? */
337 		if (cy_open == 0) {
338 			cy_open = 1;
339 			callout_reset(&cy_poll_callout, 1, cy_poll, NULL);
340 		}
341 		/* this sets parameters and raises DTR */
342 		cyparam(tp, &tp->t_termios);
343 
344 		ttsetwater(tp);
345 
346 		/* raise RTS too */
347 		cy_modem_control(sc, cy, TIOCM_RTS, DMBIS);
348 
349 		cy->cy_carrier_stat =
350 			cd_read_reg(sc, cy->cy_chip, CD1400_MSVR2);
351 
352 		/* enable receiver and modem change interrupts */
353 		cd_write_reg(sc, cy->cy_chip, CD1400_SRER,
354 		    CD1400_SRER_MDMCH | CD1400_SRER_RXDATA);
355 
356 		if (CY_DIALOUT(dev) ||
357 		    ISSET(cy->cy_openflags, TIOCFLAG_SOFTCAR) ||
358 		    ISSET(tp->t_cflag, MDMBUF) ||
359 		    ISSET(cy->cy_carrier_stat, CD1400_MSVR2_CD))
360 			SET(tp->t_state, TS_CARR_ON);
361 		else
362 			CLR(tp->t_state, TS_CARR_ON);
363 	} else if (ISSET(tp->t_state, TS_XCLUDE) && p->p_ucred->cr_uid != 0) {
364 		return EBUSY;
365 	} else {
366 		s = spltty();
367 	}
368 
369 	/* wait for carrier if necessary */
370 	if (!ISSET(flag, O_NONBLOCK)) {
371 		while (!ISSET(tp->t_cflag, CLOCAL) &&
372 		    !ISSET(tp->t_state, TS_CARR_ON)) {
373 			tp->t_wopen++;
374 			error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH,
375 			    "cydcd", 0);
376 			tp->t_wopen--;
377 			if (error != 0) {
378 				splx(s);
379 				return error;
380 			}
381 		}
382 	}
383 	splx(s);
384 
385 	return (*tp->t_linesw->l_open) (dev, tp);
386 }
387 
388 /*
389  * close routine. returns zero if successfull, else error code
390  */
391 int
392 cyclose(dev_t dev, int flag, int mode, struct proc *p)
393 {
394 	struct cy_softc *sc;
395 	struct cy_port *cy;
396 	struct tty *tp;
397 	int s;
398 
399 	cy = CY_PORT(dev);
400 	sc = CY_BOARD(cy);
401 	tp = cy->cy_tty;
402 
403 	(*tp->t_linesw->l_close) (tp, flag);
404 	s = spltty();
405 
406 	if (ISSET(tp->t_cflag, HUPCL) &&
407 	    !ISSET(cy->cy_openflags, TIOCFLAG_SOFTCAR)) {
408 		/*
409 		 * drop DTR and RTS (should we wait for output buffer to
410 		 * become empty first?)
411 		 */
412 		cy_modem_control(sc, cy, 0, DMSET);
413 	}
414 	/*
415 	 * XXX should we disable modem change and
416 	 * receive interrupts here or somewhere ?
417 	 */
418 	CLR(tp->t_state, TS_BUSY | TS_FLUSH);
419 
420 	splx(s);
421 	ttyclose(tp);
422 
423 	return 0;
424 }
425 
426 /*
427  * Read routine
428  */
429 int
430 cyread(dev_t dev, struct uio *uio, int flag)
431 {
432 	struct cy_port *cy;
433 	struct tty *tp;
434 
435 	cy = CY_PORT(dev);
436 	tp = cy->cy_tty;
437 
438 	return ((*tp->t_linesw->l_read)(tp, uio, flag));
439 }
440 
441 /*
442  * Write routine
443  */
444 int
445 cywrite(dev_t dev, struct uio *uio, int flag)
446 {
447 	struct cy_port *cy;
448 	struct tty *tp;
449 
450 	cy = CY_PORT(dev);
451 	tp = cy->cy_tty;
452 
453 	return ((*tp->t_linesw->l_write)(tp, uio, flag));
454 }
455 
456 /*
457  * Poll routine
458  */
459 int
460 cypoll(dev, events, p)
461 	dev_t dev;
462 	int events;
463 	struct proc *p;
464 {
465 	struct cy_port *cy;
466 	struct tty *tp;
467 
468 	cy = CY_PORT(dev);
469 	tp = cy->cy_tty;
470 
471 	return ((*tp->t_linesw->l_poll)(tp, events, p));
472 }
473 
474 /*
475  * return tty pointer
476  */
477 struct tty *
478 cytty(dev_t dev)
479 {
480 	struct cy_port *cy;
481 
482 	cy = CY_PORT(dev);
483 
484 	return (cy->cy_tty);
485 }
486 
487 /*
488  * ioctl routine
489  */
490 int
491 cyioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
492 {
493 	struct cy_softc *sc;
494 	struct cy_port *cy;
495 	struct tty *tp;
496 	int error;
497 
498 	cy = CY_PORT(dev);
499 	sc = CY_BOARD(cy);
500 	tp = cy->cy_tty;
501 
502 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p);
503 	if (error != EPASSTHROUGH)
504 		return error;
505 
506 	error = ttioctl(tp, cmd, data, flag, p);
507 	if (error != EPASSTHROUGH)
508 		return error;
509 
510 	/* XXX should not allow dropping DTR when dialin? */
511 
512 	switch (cmd) {
513 	case TIOCSBRK:		/* start break */
514 		SET(cy->cy_flags, CY_F_START_BREAK);
515 		cy_enable_transmitter(sc, cy);
516 		break;
517 
518 	case TIOCCBRK:		/* stop break */
519 		SET(cy->cy_flags, CY_F_END_BREAK);
520 		cy_enable_transmitter(sc, cy);
521 		break;
522 
523 	case TIOCSDTR:		/* DTR on */
524 		cy_modem_control(sc, cy, TIOCM_DTR, DMBIS);
525 		break;
526 
527 	case TIOCCDTR:		/* DTR off */
528 		cy_modem_control(sc, cy, TIOCM_DTR, DMBIC);
529 		break;
530 
531 	case TIOCMSET:		/* set new modem control line values */
532 		cy_modem_control(sc, cy, *((int *) data), DMSET);
533 		break;
534 
535 	case TIOCMBIS:		/* turn modem control bits on */
536 		cy_modem_control(sc, cy, *((int *) data), DMBIS);
537 		break;
538 
539 	case TIOCMBIC:		/* turn modem control bits off */
540 		cy_modem_control(sc, cy, *((int *) data), DMBIC);
541 		break;
542 
543 	case TIOCMGET:		/* get modem control/status line state */
544 		*((int *) data) = cy_modem_control(sc, cy, 0, DMGET);
545 		break;
546 
547 	case TIOCGFLAGS:
548 		*((int *) data) = cy->cy_openflags |
549 			(CY_DIALOUT(dev) ? TIOCFLAG_SOFTCAR : 0);
550 		break;
551 
552 	case TIOCSFLAGS:
553 		error = suser(p->p_ucred, &p->p_acflag);
554 		if (error != 0)
555 			return EPERM;
556 
557 		cy->cy_openflags = *((int *) data) &
558 		    (TIOCFLAG_SOFTCAR | TIOCFLAG_CLOCAL |
559 		     TIOCFLAG_CRTSCTS | TIOCFLAG_MDMBUF);
560 		break;
561 
562 	default:
563 		return EPASSTHROUGH;
564 	}
565 
566 	return 0;
567 }
568 
569 /*
570  * start output
571  */
572 void
573 cystart(struct tty *tp)
574 {
575 	struct cy_softc *sc;
576 	struct cy_port *cy;
577 	int s;
578 
579 	cy = CY_PORT(tp->t_dev);
580 	sc = cy->cy_softc;
581 
582 	s = spltty();
583 
584 #ifdef CY_DEBUG1
585 	cy->cy_start_count++;
586 #endif
587 
588 	if (!ISSET(tp->t_state, TS_TTSTOP | TS_TIMEOUT | TS_BUSY)) {
589 		if (tp->t_outq.c_cc <= tp->t_lowat) {
590 			if (ISSET(tp->t_state, TS_ASLEEP)) {
591 				CLR(tp->t_state, TS_ASLEEP);
592 				wakeup(&tp->t_outq);
593 			}
594 			selwakeup(&tp->t_wsel);
595 
596 			if (tp->t_outq.c_cc == 0)
597 				goto out;
598 		}
599 		SET(tp->t_state, TS_BUSY);
600 		cy_enable_transmitter(sc, cy);
601 	}
602 out:
603 
604 	splx(s);
605 }
606 
607 /*
608  * stop output
609  */
610 void
611 cystop(struct tty *tp, int flag)
612 {
613 	struct cy_port *cy;
614 	int s;
615 
616 	cy = CY_PORT(tp->t_dev);
617 
618 	s = spltty();
619 	if (ISSET(tp->t_state, TS_BUSY)) {
620 		if (!ISSET(tp->t_state, TS_TTSTOP))
621 			SET(tp->t_state, TS_FLUSH);
622 
623 		/*
624 		 * the transmit interrupt routine will disable transmit when it
625 		 * notices that CY_F_STOP has been set.
626 		 */
627 		SET(cy->cy_flags, CY_F_STOP);
628 	}
629 	splx(s);
630 }
631 
632 /*
633  * parameter setting routine.
634  * returns 0 if successfull, else returns error code
635  */
636 int
637 cyparam(struct tty *tp, struct termios *t)
638 {
639 	struct cy_softc *sc;
640 	struct cy_port *cy;
641 	int ibpr, obpr, i_clk_opt, o_clk_opt, s, opt;
642 
643 	cy = CY_PORT(tp->t_dev);
644 	sc = CY_BOARD(cy);
645 
646 	if (t->c_ospeed != 0 && cy_speed(t->c_ospeed, &o_clk_opt, &obpr, cy->cy_clock) < 0)
647 		return EINVAL;
648 
649 	if (t->c_ispeed != 0 && cy_speed(t->c_ispeed, &i_clk_opt, &ibpr, cy->cy_clock) < 0)
650 		return EINVAL;
651 
652 	s = spltty();
653 
654 	/* hang up the line is ospeed is zero, else turn DTR on */
655 	cy_modem_control(sc, cy, TIOCM_DTR, (t->c_ospeed == 0 ? DMBIC : DMBIS));
656 
657 	/* channel was selected by the above call to cy_modem_control() */
658 #if 0
659 	cd_write_reg(sc, cy->cy_chip, CD1400_CAR, port & CD1400_CAR_CHAN);
660 #endif
661 
662 	/* set transmit speed */
663 	if (t->c_ospeed != 0) {
664 		cd_write_reg(sc, cy->cy_chip, CD1400_TCOR, o_clk_opt);
665 		cd_write_reg(sc, cy->cy_chip, CD1400_TBPR, obpr);
666 	}
667 	/* set receive speed */
668 	if (t->c_ispeed != 0) {
669 		cd_write_reg(sc, cy->cy_chip, CD1400_RCOR, i_clk_opt);
670 		cd_write_reg(sc, cy->cy_chip, CD1400_RBPR, ibpr);
671 	}
672 	opt = CD1400_CCR_CMDCHANCTL | CD1400_CCR_XMTEN
673 		| (ISSET(t->c_cflag, CREAD) ? CD1400_CCR_RCVEN : CD1400_CCR_RCVDIS);
674 
675 	if (opt != cy->cy_channel_control) {
676 		cy->cy_channel_control = opt;
677 		cd1400_channel_cmd(sc, cy, opt);
678 	}
679 	/* compute COR1 contents */
680 	opt = 0;
681 	if (ISSET(t->c_cflag, PARENB)) {
682 		if (ISSET(t->c_cflag, PARODD))
683 			opt |= CD1400_COR1_PARODD;
684 		opt |= CD1400_COR1_PARNORMAL;
685 	}
686 	if (!ISSET(t->c_iflag, INPCK))
687 		opt |= CD1400_COR1_NOINPCK;	/* no parity checking */
688 
689 	if (ISSET(t->c_cflag, CSTOPB))
690 		opt |= CD1400_COR1_STOP2;
691 
692 	switch (t->c_cflag & CSIZE) {
693 	case CS5:
694 		opt |= CD1400_COR1_CS5;
695 		break;
696 
697 	case CS6:
698 		opt |= CD1400_COR1_CS6;
699 		break;
700 
701 	case CS7:
702 		opt |= CD1400_COR1_CS7;
703 		break;
704 
705 	default:
706 		opt |= CD1400_COR1_CS8;
707 		break;
708 	}
709 
710 	cd_write_reg(sc, cy->cy_chip, CD1400_COR1, opt);
711 
712 #ifdef CY_DEBUG
713 	printf("cor1 = 0x%x...", opt);
714 #endif
715 
716 	/*
717 	 * use the CD1400 automatic CTS flow control if CRTSCTS is set
718 	 *
719 	 * CD1400_COR2_ETC is used because breaks are generated with
720 	 * embedded transmit commands
721 	 */
722 	cd_write_reg(sc, cy->cy_chip, CD1400_COR2,
723 		     CD1400_COR2_ETC |
724 		 (ISSET(t->c_cflag, CRTSCTS) ? CD1400_COR2_CCTS_OFLOW : 0));
725 
726 	cd_write_reg(sc, cy->cy_chip, CD1400_COR3, CY_RX_FIFO_THRESHOLD);
727 
728 	cd1400_channel_cmd(sc, cy, CD1400_CCR_CMDCORCHG |
729 	    CD1400_CCR_COR1 | CD1400_CCR_COR2 | CD1400_CCR_COR3);
730 
731 	cd_write_reg(sc, cy->cy_chip, CD1400_COR4, CD1400_COR4_PFO_EXCEPTION);
732 	cd_write_reg(sc, cy->cy_chip, CD1400_COR5, 0);
733 
734 	/*
735          * set modem change option registers to generate interrupts
736          * on carrier detect changes.
737          *
738          * if hardware RTS handshaking is used
739          * also set the handshaking threshold.
740          */
741 	if (cy->cy_clock == CY_CLOCK_60) {
742 	   cd_write_reg(sc, cy->cy_chip, CD1400_MCOR1, CD1400_MCOR1_CDzd |
743     	      (ISSET(t->c_cflag, CRTSCTS) ? CY_RX_DTR_THRESHOLD : 0));
744 	} else {
745 	   cd_write_reg(sc, cy->cy_chip, CD1400_MCOR1, CD1400_MCOR1_CDzd);
746 	}
747 
748 	cd_write_reg(sc, cy->cy_chip, CD1400_MCOR2, CD1400_MCOR2_CDod);
749 
750 	/*
751          * set receive timeout to approx. 2ms
752          * could use more complex logic here...
753          * (but is it actually needed or even useful?)
754          */
755 	cd_write_reg(sc, cy->cy_chip, CD1400_RTPR, 2);
756 
757 	/*
758          * should do anything else here?
759          * XXX check MDMBUF handshaking like in com.c?
760          */
761 
762 	splx(s);
763 	return 0;
764 }
765 
766 /*
767  * set/get modem line status
768  *
769  * bits can be: TIOCM_DTR, TIOCM_RTS, TIOCM_CTS, TIOCM_CD, TIOCM_RI, TIOCM_DSR
770  */
771 int
772 cy_modem_control(struct cy_softc *sc, struct cy_port *cy, int bits, int howto)
773 {
774 	struct tty *tp = cy->cy_tty;
775 	int s, msvr;
776 
777 	s = spltty();
778 
779 	/* select channel */
780 	cd_write_reg(sc, cy->cy_chip, CD1400_CAR,
781 	    cy->cy_port_num & CD1400_CAR_CHAN);
782 
783 	/* Does not manipulate RTS if it is used for flow control. */
784 	switch (howto) {
785 	case DMGET:
786 		bits = 0;
787 		if (cy->cy_channel_control & CD1400_CCR_RCVEN)
788 			bits |= TIOCM_LE;
789 		msvr = cd_read_reg(sc, cy->cy_chip, CD1400_MSVR2);
790 		if (cy->cy_clock == CY_CLOCK_60) {
791 			if (cd_read_reg(sc, cy->cy_chip, CD1400_MSVR1) &
792 		    		CD1400_MSVR1_RTS)
793 				bits |= TIOCM_DTR;
794 			if (msvr & CD1400_MSVR2_DTR)
795 				bits |= TIOCM_RTS;
796 		} else {
797 			if (cd_read_reg(sc, cy->cy_chip, CD1400_MSVR1) &
798 			    CD1400_MSVR1_RTS)
799 				bits |= TIOCM_RTS;
800 			if (msvr & CD1400_MSVR2_DTR)
801 				bits |= TIOCM_DTR;
802 		}
803 		if (msvr & CD1400_MSVR2_CTS)
804 			bits |= TIOCM_CTS;
805 		if (msvr & CD1400_MSVR2_CD)
806 			bits |= TIOCM_CD;
807 		/* Not connected on some Cyclom-Y boards? */
808 		if (msvr & CD1400_MSVR2_DSR)
809 			bits |= TIOCM_DSR;
810 		/* Not connected on some Cyclom-8Y boards? */
811 		if (msvr & CD1400_MSVR2_RI)
812 			bits |= TIOCM_RI;
813 		break;
814 
815 	case DMSET:		/* replace old values with new ones */
816 		if (cy->cy_clock == CY_CLOCK_60) {
817 			if (!ISSET(tp->t_cflag, CRTSCTS))
818 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR2,
819 				   ((bits & TIOCM_RTS) ? CD1400_MSVR2_DTR : 0));
820 			cd_write_reg(sc, cy->cy_chip, CD1400_MSVR1,
821 			    ((bits & TIOCM_DTR) ? CD1400_MSVR1_RTS : 0));
822 		} else {
823 			if (!ISSET(tp->t_cflag, CRTSCTS))
824 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR1,
825 				   ((bits & TIOCM_RTS) ? CD1400_MSVR1_RTS : 0));
826 			cd_write_reg(sc, cy->cy_chip, CD1400_MSVR2,
827 			    ((bits & TIOCM_DTR) ? CD1400_MSVR2_DTR : 0));
828 		}
829 		break;
830 
831 	case DMBIS:		/* set bits */
832 		if (cy->cy_clock == CY_CLOCK_60) {
833 			if (!ISSET(tp->t_cflag, CRTSCTS) &&
834 			    (bits & TIOCM_RTS) != 0)
835 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR2,
836 				    CD1400_MSVR2_DTR);
837 			if (bits & TIOCM_DTR)
838 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR1,
839 				    CD1400_MSVR1_RTS);
840 		} else {
841 			if (!ISSET(tp->t_cflag, CRTSCTS) &&
842 			    (bits & TIOCM_RTS) != 0)
843 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR1,
844 				    CD1400_MSVR1_RTS);
845 			if (bits & TIOCM_DTR)
846 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR2,
847 				    CD1400_MSVR2_DTR);
848 		}
849 		break;
850 
851 	case DMBIC:		/* clear bits */
852 		if (cy->cy_clock == CY_CLOCK_60) {
853 			if (!ISSET(tp->t_cflag, CRTSCTS) && (bits & TIOCM_RTS))
854 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR2, 0);
855 			if (bits & TIOCM_DTR)
856 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR1, 0);
857 		} else {
858 			if (!ISSET(tp->t_cflag, CRTSCTS) && (bits & TIOCM_RTS))
859 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR1, 0);
860 			if (bits & TIOCM_DTR)
861 				cd_write_reg(sc, cy->cy_chip, CD1400_MSVR2, 0);
862 		}
863 		break;
864 	}
865 	splx(s);
866 	return ((howto == DMGET) ? bits : 0);
867 }
868 
869 /*
870  * Upper-level handler loop (called from timer interrupt?)
871  * This routine is common for multiple cards
872  */
873 void
874 cy_poll(void *arg)
875 {
876 	int card, port;
877 	struct cy_softc *sc;
878 	struct cy_port *cy;
879 	struct tty *tp;
880 	static int counter = 0;
881 #ifdef CY_DEBUG1
882 	int did_something;
883 #endif
884 	int s = spltty();
885 
886 	if (cy_events == 0 && ++counter < 200) {
887 		splx(s);
888 		goto out;
889 	}
890 	cy_events = 0;
891 	splx(s);
892 
893 	for (card = 0; card < cy_cd.cd_ndevs; card++) {
894 		sc = device_lookup(&cy_cd, card);
895 		if (sc == NULL)
896 			continue;
897 
898 #ifdef CY_DEBUG1
899 		sc->sc_poll_count1++;
900 		did_something = 0;
901 #endif
902 
903 		for (port = 0; port < sc->sc_nchannels; port++) {
904 			cy = &sc->sc_ports[port];
905 			if ((tp = cy->cy_tty) == NULL || cy->cy_ibuf == NULL ||
906 			    (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0))
907 				continue;
908 
909 			/*
910 		         * handle received data
911 		         */
912 			while (cy->cy_ibuf_rd_ptr != cy->cy_ibuf_wr_ptr) {
913 				u_char line_stat;
914 				int chr;
915 
916 				line_stat = cy->cy_ibuf_rd_ptr[0];
917 				chr = cy->cy_ibuf_rd_ptr[1];
918 
919 				if (line_stat &
920 				    (CD1400_RDSR_BREAK | CD1400_RDSR_FE))
921 					chr |= TTY_FE;
922 				if (line_stat & CD1400_RDSR_PE)
923 					chr |= TTY_PE;
924 
925 				/*
926 				 * on an overrun error the data is treated as
927 				 * good just as it should be.
928 				 */
929 
930 #ifdef CY_DEBUG
931 				printf("%s: port %d ttyinput 0x%x\n",
932 				    sc->sc_dev.dv_xname, port, chr);
933 #endif
934 
935 				(*tp->t_linesw->l_rint) (chr, tp);
936 
937 				s = spltty();	/* really necessary? */
938 				if ((cy->cy_ibuf_rd_ptr += 2) ==
939 				    cy->cy_ibuf_end)
940 					cy->cy_ibuf_rd_ptr = cy->cy_ibuf;
941 				splx(s);
942 
943 #ifdef CY_DEBUG1
944 				did_something = 1;
945 #endif
946 			}
947 
948 			/*
949 			 * If we don't have any received data in ibuf and
950 			 * CRTSCTS is on and RTS is turned off, it is time to
951 			 * turn RTS back on
952 			 */
953 			if (ISSET(tp->t_cflag, CRTSCTS)) {
954 				/*
955 				 * we can't use cy_modem_control() here as it
956 				 * doesn't change RTS if RTSCTS is on
957 				 */
958 				cd_write_reg(sc, cy->cy_chip, CD1400_CAR,
959 				    port & CD1400_CAR_CHAN);
960 
961 				if (cy->cy_clock == CY_CLOCK_60) {
962 				  if ((cd_read_reg(sc, cy->cy_chip,
963 				    CD1400_MSVR2) & CD1400_MSVR2_DTR) == 0) {
964 					cd_write_reg(sc, cy->cy_chip,
965 					CD1400_MSVR2,CD1400_MSVR2_DTR);
966 #ifdef CY_DEBUG1
967 					did_something = 1;
968 #endif
969 				  }
970 				} else {
971 				  if ((cd_read_reg(sc, cy->cy_chip,
972 				    CD1400_MSVR1) & CD1400_MSVR1_RTS) == 0) {
973 					cd_write_reg(sc, cy->cy_chip,
974 					CD1400_MSVR1,CD1400_MSVR1_RTS);
975 #ifdef CY_DEBUG1
976 					did_something = 1;
977 #endif
978 				  }
979 				}
980 			}
981 
982 			/*
983 		         * handle carrier changes
984 		         */
985 			s = spltty();
986 			if (ISSET(cy->cy_flags, CY_F_CARRIER_CHANGED)) {
987 				int             carrier;
988 
989 				CLR(cy->cy_flags, CY_F_CARRIER_CHANGED);
990 				splx(s);
991 
992 				carrier = ((cy->cy_carrier_stat &
993 				    CD1400_MSVR2_CD) != 0);
994 
995 #ifdef CY_DEBUG
996 				printf("cy_poll: carrier change "
997 				    "(card %d, port %d, carrier %d)\n",
998 				    card, port, carrier);
999 #endif
1000 				if (CY_DIALOUT(tp->t_dev) == 0 &&
1001 				    !(*tp->t_linesw->l_modem)(tp, carrier))
1002 					cy_modem_control(sc, cy,
1003 					    TIOCM_DTR, DMBIC);
1004 
1005 #ifdef CY_DEBUG1
1006 				did_something = 1;
1007 #endif
1008 			} else
1009 				splx(s);
1010 
1011 			s = spltty();
1012 			if (ISSET(cy->cy_flags, CY_F_START)) {
1013 				CLR(cy->cy_flags, CY_F_START);
1014 				splx(s);
1015 
1016 				(*tp->t_linesw->l_start) (tp);
1017 
1018 #ifdef CY_DEBUG1
1019 				did_something = 1;
1020 #endif
1021 			} else
1022 				splx(s);
1023 
1024 			/* could move this to even upper level... */
1025 			if (cy->cy_fifo_overruns) {
1026 				cy->cy_fifo_overruns = 0;
1027 				/*
1028 				 * doesn't report overrun count, but
1029 				 * shouldn't really matter
1030 				 */
1031 				log(LOG_WARNING, "%s: port %d fifo overrun\n",
1032 				    sc->sc_dev.dv_xname, port);
1033 			}
1034 			if (cy->cy_ibuf_overruns) {
1035 				cy->cy_ibuf_overruns = 0;
1036 				log(LOG_WARNING, "%s: port %d ibuf overrun\n",
1037 				    sc->sc_dev.dv_xname, port);
1038 			}
1039 		}		/* for(port...) */
1040 #ifdef CY_DEBUG1
1041 		if (did_something && counter >= 200)
1042 			sc->sc_poll_count2++;
1043 #endif
1044 	} /* for(card...) */
1045 
1046 	counter = 0;
1047 
1048 out:
1049 	callout_reset(&cy_poll_callout, 1, cy_poll, NULL);
1050 }
1051 
1052 /*
1053  * hardware interrupt routine
1054  */
1055 int
1056 cy_intr(void *arg)
1057 {
1058 	struct cy_softc *sc = arg;
1059 	struct cy_port *cy;
1060 	int cy_chip, stat;
1061 	int int_serviced = 0;
1062 
1063 	/*
1064 	 * Check interrupt status of each CD1400 chip on this card
1065 	 * (multiple cards cannot share the same interrupt)
1066 	 */
1067 	for (cy_chip = 0; cy_chip < sc->sc_nchips; cy_chip++) {
1068 
1069 		stat = cd_read_reg(sc, cy_chip, CD1400_SVRR);
1070 		if (stat == 0)
1071 			continue;
1072 
1073 		if (ISSET(stat, CD1400_SVRR_RXRDY)) {
1074 			u_char save_car, save_rir, serv_type;
1075 			u_char line_stat, recv_data, n_chars;
1076 			u_char *buf_p;
1077 
1078 			save_rir = cd_read_reg(sc, cy_chip, CD1400_RIR);
1079 			save_car = cd_read_reg(sc, cy_chip, CD1400_CAR);
1080 			/* enter rx service */
1081 			cd_write_reg(sc, cy_chip, CD1400_CAR, save_rir);
1082 
1083 			serv_type = cd_read_reg(sc, cy_chip, CD1400_RIVR);
1084 			cy = &sc->sc_ports[serv_type >> 3];
1085 
1086 #ifdef CY_DEBUG1
1087 			cy->cy_rx_int_count++;
1088 #endif
1089 
1090 			buf_p = cy->cy_ibuf_wr_ptr;
1091 
1092 			if (ISSET(serv_type, CD1400_RIVR_EXCEPTION)) {
1093 				line_stat = cd_read_reg(sc, cy->cy_chip,
1094 				    CD1400_RDSR);
1095 				recv_data = cd_read_reg(sc, cy->cy_chip,
1096 				    CD1400_RDSR);
1097 
1098 				if (cy->cy_tty == NULL ||
1099 				    !ISSET(cy->cy_tty->t_state, TS_ISOPEN))
1100 					goto end_rx_serv;
1101 
1102 #ifdef CY_DEBUG
1103 				printf("%s port %d recv exception, line_stat 0x%x, char 0x%x\n",
1104 				sc->sc_dev.dv_xname, cy->cy_port_num, line_stat, recv_data);
1105 #endif
1106 				if (ISSET(line_stat, CD1400_RDSR_OE))
1107 					cy->cy_fifo_overruns++;
1108 
1109 				*buf_p++ = line_stat;
1110 				*buf_p++ = recv_data;
1111 				if (buf_p == cy->cy_ibuf_end)
1112 					buf_p = cy->cy_ibuf;
1113 
1114 				if (buf_p == cy->cy_ibuf_rd_ptr) {
1115 					if (buf_p == cy->cy_ibuf)
1116 						buf_p = cy->cy_ibuf_end;
1117 					buf_p -= 2;
1118 					cy->cy_ibuf_overruns++;
1119 				}
1120 				cy_events = 1;
1121 			} else {/* no exception, received data OK */
1122 				n_chars = cd_read_reg(sc, cy->cy_chip,
1123 				    CD1400_RDCR);
1124 
1125 				/* If no tty or not open, discard data */
1126 				if (cy->cy_tty == NULL ||
1127 				    !ISSET(cy->cy_tty->t_state, TS_ISOPEN)) {
1128 					while (n_chars--)
1129 						cd_read_reg(sc, cy->cy_chip,
1130 							    CD1400_RDSR);
1131 					goto end_rx_serv;
1132 				}
1133 
1134 #ifdef CY_DEBUG
1135 				printf("%s port %d receive ok %d chars\n",
1136 				    sc->sc_dev.dv_xname, cy->cy_port_num, n_chars);
1137 #endif
1138 				while (n_chars--) {
1139 					*buf_p++ = 0;	/* status: OK */
1140 					/* data byte */
1141 					*buf_p++ = cd_read_reg(sc,
1142 					    cy->cy_chip, CD1400_RDSR);
1143 					if (buf_p == cy->cy_ibuf_end)
1144 						buf_p = cy->cy_ibuf;
1145 					if (buf_p == cy->cy_ibuf_rd_ptr) {
1146 						if (buf_p == cy->cy_ibuf)
1147 							buf_p = cy->cy_ibuf_end;
1148 						buf_p -= 2;
1149 						cy->cy_ibuf_overruns++;
1150 						break;
1151 					}
1152 				}
1153 				cy_events = 1;
1154 			}
1155 
1156 			cy->cy_ibuf_wr_ptr = buf_p;
1157 
1158 			/* RTS handshaking for incoming data */
1159 			if (ISSET(cy->cy_tty->t_cflag, CRTSCTS)) {
1160 				int bf, msvr;
1161 
1162 				bf = buf_p - cy->cy_ibuf_rd_ptr;
1163 				if (bf < 0)
1164 					bf += CY_IBUF_SIZE;
1165 
1166 				if (bf > (CY_IBUF_SIZE / 2)) {
1167 					/* turn RTS off */
1168 					if (cy->cy_clock == CY_CLOCK_60)
1169 						msvr = CD1400_MSVR2;
1170 					else
1171 						msvr = CD1400_MSVR1;
1172 					cd_write_reg(sc, cy->cy_chip, msvr, 0);
1173 				}
1174 			}
1175 
1176 	end_rx_serv:
1177 			/* terminate service context */
1178 			cd_write_reg(sc, cy->cy_chip, CD1400_RIR,
1179 				     save_rir & 0x3f);
1180 			cd_write_reg(sc, cy->cy_chip, CD1400_CAR, save_car);
1181 			int_serviced = 1;
1182 		} /* if (rx_service...) */
1183 		if (ISSET(stat, CD1400_SVRR_MDMCH)) {
1184 			u_char save_car, save_mir, serv_type, modem_stat;
1185 
1186 			save_mir = cd_read_reg(sc, cy_chip, CD1400_MIR);
1187 			save_car = cd_read_reg(sc, cy_chip, CD1400_CAR);
1188 			/* enter modem service */
1189 			cd_write_reg(sc, cy_chip, CD1400_CAR, save_mir);
1190 
1191 			serv_type = cd_read_reg(sc, cy_chip, CD1400_MIVR);
1192 			cy = &sc->sc_ports[serv_type >> 3];
1193 
1194 #ifdef CY_DEBUG1
1195 			cy->cy_modem_int_count++;
1196 #endif
1197 
1198 			modem_stat = cd_read_reg(sc, cy->cy_chip, CD1400_MSVR2);
1199 
1200 #ifdef CY_DEBUG
1201 			printf("%s port %d modem line change, new stat 0x%x\n",
1202 			       sc->sc_dev.dv_xname, cy->cy_port_num, modem_stat);
1203 #endif
1204 			if (ISSET((cy->cy_carrier_stat ^ modem_stat), CD1400_MSVR2_CD)) {
1205 				SET(cy->cy_flags, CY_F_CARRIER_CHANGED);
1206 				cy_events = 1;
1207 			}
1208 			cy->cy_carrier_stat = modem_stat;
1209 
1210 			/* terminate service context */
1211 			cd_write_reg(sc, cy->cy_chip, CD1400_MIR, save_mir & 0x3f);
1212 			cd_write_reg(sc, cy->cy_chip, CD1400_CAR, save_car);
1213 			int_serviced = 1;
1214 		} /* if (modem_service...) */
1215 		if (ISSET(stat, CD1400_SVRR_TXRDY)) {
1216 			u_char          save_car, save_tir, serv_type,
1217 			                count, ch;
1218 			struct tty     *tp;
1219 
1220 			save_tir = cd_read_reg(sc, cy_chip, CD1400_TIR);
1221 			save_car = cd_read_reg(sc, cy_chip, CD1400_CAR);
1222 			/* enter tx service */
1223 			cd_write_reg(sc, cy_chip, CD1400_CAR, save_tir);
1224 
1225 			serv_type = cd_read_reg(sc, cy_chip, CD1400_TIVR);
1226 			cy = &sc->sc_ports[serv_type >> 3];
1227 
1228 #ifdef CY_DEBUG1
1229 			cy->cy_tx_int_count++;
1230 #endif
1231 #ifdef CY_DEBUG
1232 			printf("%s port %d tx service\n", sc->sc_dev.dv_xname,
1233 			    cy->cy_port_num);
1234 #endif
1235 
1236 			/* stop transmitting if no tty or CY_F_STOP set */
1237 			tp = cy->cy_tty;
1238 			if (tp == NULL || ISSET(cy->cy_flags, CY_F_STOP))
1239 				goto txdone;
1240 
1241 			count = 0;
1242 			if (ISSET(cy->cy_flags, CY_F_SEND_NUL)) {
1243 				cd_write_reg(sc, cy->cy_chip, CD1400_TDR, 0);
1244 				cd_write_reg(sc, cy->cy_chip, CD1400_TDR, 0);
1245 				count += 2;
1246 				CLR(cy->cy_flags, CY_F_SEND_NUL);
1247 			}
1248 			if (tp->t_outq.c_cc > 0) {
1249 				SET(tp->t_state, TS_BUSY);
1250 				while (tp->t_outq.c_cc > 0 &&
1251 				    count < CD1400_TX_FIFO_SIZE) {
1252 					ch = getc(&tp->t_outq);
1253 					/*
1254 					 * remember to double NUL characters
1255 					 * because embedded transmit commands
1256 					 * are enabled
1257 					 */
1258 					if (ch == 0) {
1259 						if (count >= CD1400_TX_FIFO_SIZE - 2) {
1260 							SET(cy->cy_flags, CY_F_SEND_NUL);
1261 							break;
1262 						}
1263 						cd_write_reg(sc, cy->cy_chip,
1264 						    CD1400_TDR, ch);
1265 						count++;
1266 					}
1267 					cd_write_reg(sc, cy->cy_chip,
1268 					    CD1400_TDR, ch);
1269 					count++;
1270 				}
1271 			} else {
1272 				/*
1273 				 * no data to send -- check if we should
1274 				 * start/stop a break
1275 				 */
1276 				/*
1277 				 * XXX does this cause too much delay before
1278 				 * breaks?
1279 				 */
1280 				if (ISSET(cy->cy_flags, CY_F_START_BREAK)) {
1281 					cd_write_reg(sc, cy->cy_chip,
1282 					    CD1400_TDR, 0);
1283 					cd_write_reg(sc, cy->cy_chip,
1284 					    CD1400_TDR, 0x81);
1285 					CLR(cy->cy_flags, CY_F_START_BREAK);
1286 				}
1287 				if (ISSET(cy->cy_flags, CY_F_END_BREAK)) {
1288 					cd_write_reg(sc, cy->cy_chip,
1289 					    CD1400_TDR, 0);
1290 					cd_write_reg(sc, cy->cy_chip,
1291 					    CD1400_TDR, 0x83);
1292 					CLR(cy->cy_flags, CY_F_END_BREAK);
1293 				}
1294 			}
1295 
1296 			if (tp->t_outq.c_cc == 0) {
1297 		txdone:
1298 				/*
1299 				 * No data to send or requested to stop.
1300 				 * Disable transmit interrupt
1301 				 */
1302 				cd_write_reg(sc, cy->cy_chip, CD1400_SRER,
1303 				     cd_read_reg(sc, cy->cy_chip, CD1400_SRER)
1304 				     & ~CD1400_SRER_TXRDY);
1305 				CLR(cy->cy_flags, CY_F_STOP);
1306 				CLR(tp->t_state, TS_BUSY);
1307 			}
1308 			if (tp->t_outq.c_cc <= tp->t_lowat) {
1309 				SET(cy->cy_flags, CY_F_START);
1310 				cy_events = 1;
1311 			}
1312 			/* terminate service context */
1313 			cd_write_reg(sc, cy->cy_chip, CD1400_TIR, save_tir & 0x3f);
1314 			cd_write_reg(sc, cy->cy_chip, CD1400_CAR, save_car);
1315 			int_serviced = 1;
1316 		}		/* if (tx_service...) */
1317 	}			/* for(...all CD1400s on a card) */
1318 
1319 	/* ensure an edge for next interrupt */
1320 	bus_space_write_1(sc->sc_memt, sc->sc_bsh,
1321 			CY_CLEAR_INTR << sc->sc_bustype, 0);
1322 	return int_serviced;
1323 }
1324 
1325 /*
1326  * subroutine to enable CD1400 transmitter
1327  */
1328 void
1329 cy_enable_transmitter(struct cy_softc *sc, struct cy_port *cy)
1330 {
1331 	int s = spltty();
1332 	cd_write_reg(sc, cy->cy_chip, CD1400_CAR,
1333 	    cy->cy_port_num & CD1400_CAR_CHAN);
1334 	cd_write_reg(sc, cy->cy_chip, CD1400_SRER,
1335 	    cd_read_reg(sc, cy->cy_chip, CD1400_SRER) | CD1400_SRER_TXRDY);
1336 	splx(s);
1337 }
1338 
1339 /*
1340  * Execute a CD1400 channel command
1341  */
1342 void
1343 cd1400_channel_cmd(struct cy_softc *sc, struct cy_port *cy, int cmd)
1344 {
1345 	u_int waitcnt = 5 * 8 * 1024;	/* approx 5 ms */
1346 
1347 #ifdef CY_DEBUG
1348 	printf("c1400_channel_cmd cy %p command 0x%x\n", cy, cmd);
1349 #endif
1350 
1351 	/* wait until cd1400 is ready to process a new command */
1352 	while (cd_read_reg(sc, cy->cy_chip, CD1400_CCR) != 0 && waitcnt-- > 0);
1353 
1354 	if (waitcnt == 0)
1355 		log(LOG_ERR, "%s: channel command timeout\n",
1356 		    sc->sc_dev.dv_xname);
1357 
1358 	cd_write_reg(sc, cy->cy_chip, CD1400_CCR, cmd);
1359 }
1360 
1361 /*
1362  * Compute clock option register and baud rate register values
1363  * for a given speed. Return 0 on success, -1 on failure.
1364  *
1365  * The error between requested and actual speed seems
1366  * to be well within allowed limits (less than 3%)
1367  * with every speed value between 50 and 150000 bps.
1368  */
1369 int
1370 cy_speed(speed_t speed, int *cor, int *bpr, int cy_clock)
1371 {
1372 	int c, co, br;
1373 
1374 	if (speed < 50 || speed > 150000)
1375 		return -1;
1376 
1377 	for (c = 0, co = 8; co <= 2048; co <<= 2, c++) {
1378 		br = (cy_clock + (co * speed) / 2) / (co * speed);
1379 		if (br < 0x100) {
1380 			*bpr = br;
1381 			*cor = c;
1382 			return 0;
1383 		}
1384 	}
1385 
1386 	return -1;
1387 }
1388