xref: /titanic_50/usr/src/uts/common/io/asy.c (revision d2b5b2d357ee3172eacb6860be1891259902203d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*	Copyright (c) 1990, 1991 UNIX System Laboratories, Inc.	*/
23 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T	*/
24 /*	  All Rights Reserved					*/
25 
26 /*
27  * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
28  */
29 
30 
31 /*
32  * Serial I/O driver for 8250/16450/16550A/16650/16750 chips.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/types.h>
37 #include <sys/signal.h>
38 #include <sys/stream.h>
39 #include <sys/termio.h>
40 #include <sys/errno.h>
41 #include <sys/file.h>
42 #include <sys/cmn_err.h>
43 #include <sys/stropts.h>
44 #include <sys/strsubr.h>
45 #include <sys/strtty.h>
46 #include <sys/debug.h>
47 #include <sys/kbio.h>
48 #include <sys/cred.h>
49 #include <sys/stat.h>
50 #include <sys/consdev.h>
51 #include <sys/mkdev.h>
52 #include <sys/kmem.h>
53 #include <sys/cred.h>
54 #include <sys/strsun.h>
55 #ifdef DEBUG
56 #include <sys/promif.h>
57 #endif
58 #include <sys/modctl.h>
59 #include <sys/ddi.h>
60 #include <sys/sunddi.h>
61 #include <sys/pci.h>
62 #include <sys/asy.h>
63 #include <sys/policy.h>
64 
65 /*
66  * set the RX FIFO trigger_level to half the RX FIFO size for now
67  * we may want to make this configurable later.
68  */
69 static	int asy_trig_level = FIFO_TRIG_8;
70 
71 int asy_drain_check = 15000000;		/* tunable: exit drain check time */
72 int asy_min_dtr_low = 500000;		/* tunable: minimum DTR down time */
73 int asy_min_utbrk = 100000;		/* tunable: minumum untimed brk time */
74 
75 int asymaxchip = ASY16750;	/* tunable: limit chip support we look for */
76 
77 /*
78  * Just in case someone has a chip with broken loopback mode, we provide a
79  * means to disable the loopback test. By default, we only loopback test
80  * UARTs which look like they have FIFOs bigger than 16 bytes.
81  * Set to 0 to suppress test, or to 2 to enable test on any size FIFO.
82  */
83 int asy_fifo_test = 1;		/* tunable: set to 0, 1, or 2 */
84 
85 /*
86  * Allow ability to switch off testing of the scratch register.
87  * Some UART emulators might not have it. This will also disable the test
88  * for Exar/Startech ST16C650, as that requires use of the SCR register.
89  */
90 int asy_scr_test = 1;		/* tunable: set to 0 to disable SCR reg test */
91 
92 /*
93  * As we don't yet support on-chip flow control, it's a bad idea to put a
94  * large number of characters in the TX FIFO, since if other end tells us
95  * to stop transmitting, we can only stop filling the TX FIFO, but it will
96  * still carry on draining by itself, so remote end still gets what's left
97  * in the FIFO.
98  */
99 int asy_max_tx_fifo = 16;	/* tunable: max fill of TX FIFO */
100 
101 #define	async_stopc	async_ttycommon.t_stopc
102 #define	async_startc	async_ttycommon.t_startc
103 
104 #define	ASY_INIT	1
105 #define	ASY_NOINIT	0
106 
107 /* enum value for sw and hw flow control action */
108 typedef enum {
109 	FLOW_CHECK,
110 	FLOW_STOP,
111 	FLOW_START
112 } async_flowc_action;
113 
114 #ifdef DEBUG
115 #define	ASY_DEBUG_INIT	0x0001	/* Output msgs during driver initialization. */
116 #define	ASY_DEBUG_INPUT	0x0002	/* Report characters received during int. */
117 #define	ASY_DEBUG_EOT	0x0004	/* Output msgs when wait for xmit to finish. */
118 #define	ASY_DEBUG_CLOSE	0x0008	/* Output msgs when driver open/close called */
119 #define	ASY_DEBUG_HFLOW	0x0010	/* Output msgs when H/W flowcontrol is active */
120 #define	ASY_DEBUG_PROCS	0x0020	/* Output each proc name as it is entered. */
121 #define	ASY_DEBUG_STATE	0x0040	/* Output value of Interrupt Service Reg. */
122 #define	ASY_DEBUG_INTR	0x0080	/* Output value of Interrupt Service Reg. */
123 #define	ASY_DEBUG_OUT	0x0100	/* Output msgs about output events. */
124 #define	ASY_DEBUG_BUSY	0x0200	/* Output msgs when xmit is enabled/disabled */
125 #define	ASY_DEBUG_MODEM	0x0400	/* Output msgs about modem status & control. */
126 #define	ASY_DEBUG_MODM2	0x0800	/* Output msgs about modem status & control. */
127 #define	ASY_DEBUG_IOCTL	0x1000	/* Output msgs about ioctl messages. */
128 #define	ASY_DEBUG_CHIP	0x2000	/* Output msgs about chip identification. */
129 #define	ASY_DEBUG_SFLOW	0x4000	/* Output msgs when S/W flowcontrol is active */
130 #define	ASY_DEBUG(x) (debug & (x))
131 static	int debug  = 0;
132 #else
133 #define	ASY_DEBUG(x) B_FALSE
134 #endif
135 
136 /* pnpISA compressed device ids */
137 #define	pnpMTS0219 0xb6930219	/* Multitech MT5634ZTX modem */
138 
139 /*
140  * PPS (Pulse Per Second) support.
141  */
142 void ddi_hardpps();
143 /*
144  * This is protected by the asy_excl_hi of the port on which PPS event
145  * handling is enabled.  Note that only one port should have this enabled at
146  * any one time.  Enabling PPS handling on multiple ports will result in
147  * unpredictable (but benign) results.
148  */
149 static struct ppsclockev asy_ppsev;
150 
151 #ifdef PPSCLOCKLED
152 /* XXX Use these to observe PPS latencies and jitter on a scope */
153 #define	LED_ON
154 #define	LED_OFF
155 #else
156 #define	LED_ON
157 #define	LED_OFF
158 #endif
159 
160 static	int max_asy_instance = -1;
161 
162 static	uint_t	asysoftintr(caddr_t intarg);
163 static	uint_t	asyintr(caddr_t argasy);
164 
165 static boolean_t abort_charseq_recognize(uchar_t ch);
166 
167 /* The async interrupt entry points */
168 static void	async_txint(struct asycom *asy);
169 static void	async_rxint(struct asycom *asy, uchar_t lsr);
170 static void	async_msint(struct asycom *asy);
171 static void	async_softint(struct asycom *asy);
172 
173 static void	async_ioctl(struct asyncline *async, queue_t *q, mblk_t *mp);
174 static void	async_reioctl(void *unit);
175 static void	async_iocdata(queue_t *q, mblk_t *mp);
176 static void	async_restart(void *arg);
177 static void	async_start(struct asyncline *async);
178 static void	async_nstart(struct asyncline *async, int mode);
179 static void	async_resume(struct asyncline *async);
180 static void	asy_program(struct asycom *asy, int mode);
181 static void	asyinit(struct asycom *asy);
182 static void	asy_waiteot(struct asycom *asy);
183 static void	asyputchar(cons_polledio_arg_t, uchar_t c);
184 static int	asygetchar(cons_polledio_arg_t);
185 static boolean_t	asyischar(cons_polledio_arg_t);
186 
187 static int	asymctl(struct asycom *, int, int);
188 static int	asytodm(int, int);
189 static int	dmtoasy(int);
190 /*PRINTFLIKE2*/
191 static void	asyerror(int level, const char *fmt, ...) __KPRINTFLIKE(2);
192 static void	asy_parse_mode(dev_info_t *devi, struct asycom *asy);
193 static void	asy_soft_state_free(struct asycom *);
194 static char	*asy_hw_name(struct asycom *asy);
195 static void	async_hold_utbrk(void *arg);
196 static void	async_resume_utbrk(struct asyncline *async);
197 static void	async_dtr_free(struct asyncline *async);
198 static int	asy_identify_chip(dev_info_t *devi, struct asycom *asy);
199 static void	asy_reset_fifo(struct asycom *asy, uchar_t flags);
200 static int	asy_getproperty(dev_info_t *devi, struct asycom *asy,
201 		    const char *property);
202 static boolean_t	async_flowcontrol_sw_input(struct asycom *asy,
203 			    async_flowc_action onoff, int type);
204 static void	async_flowcontrol_sw_output(struct asycom *asy,
205 		    async_flowc_action onoff);
206 static void	async_flowcontrol_hw_input(struct asycom *asy,
207 		    async_flowc_action onoff, int type);
208 static void	async_flowcontrol_hw_output(struct asycom *asy,
209 		    async_flowc_action onoff);
210 
211 #define	GET_PROP(devi, pname, pflag, pval, plen) \
212 		(ddi_prop_op(DDI_DEV_T_ANY, (devi), PROP_LEN_AND_VAL_BUF, \
213 		(pflag), (pname), (caddr_t)(pval), (plen)))
214 
215 kmutex_t asy_glob_lock; /* lock protecting global data manipulation */
216 void *asy_soft_state;
217 
218 /* Standard COM port I/O addresses */
219 static const int standard_com_ports[] = {
220 	COM1_IOADDR, COM2_IOADDR, COM3_IOADDR, COM4_IOADDR
221 };
222 
223 static int *com_ports;
224 static uint_t num_com_ports;
225 
226 #ifdef	DEBUG
227 /*
228  * Set this to true to make the driver pretend to do a suspend.  Useful
229  * for debugging suspend/resume code with a serial debugger.
230  */
231 boolean_t	asy_nosuspend = B_FALSE;
232 #endif
233 
234 
235 /*
236  * Baud rate table. Indexed by #defines found in sys/termios.h
237  */
238 ushort_t asyspdtab[] = {
239 	0,	/* 0 baud rate */
240 	0x900,	/* 50 baud rate */
241 	0x600,	/* 75 baud rate */
242 	0x417,	/* 110 baud rate (%0.026) */
243 	0x359,	/* 134 baud rate (%0.058) */
244 	0x300,	/* 150 baud rate */
245 	0x240,	/* 200 baud rate */
246 	0x180,	/* 300 baud rate */
247 	0x0c0,	/* 600 baud rate */
248 	0x060,	/* 1200 baud rate */
249 	0x040,	/* 1800 baud rate */
250 	0x030,	/* 2400 baud rate */
251 	0x018,	/* 4800 baud rate */
252 	0x00c,	/* 9600 baud rate */
253 	0x006,	/* 19200 baud rate */
254 	0x003,	/* 38400 baud rate */
255 
256 	0x002,	/* 57600 baud rate */
257 	0x0,	/* 76800 baud rate not supported */
258 	0x001,	/* 115200 baud rate */
259 	0x0,	/* 153600 baud rate not supported */
260 	0x0,	/* 0x8002 (SMC chip) 230400 baud rate not supported */
261 	0x0,	/* 307200 baud rate not supported */
262 	0x0,	/* 0x8001 (SMC chip) 460800 baud rate not supported */
263 	0x0,	/* unused */
264 	0x0,	/* unused */
265 	0x0,	/* unused */
266 	0x0,	/* unused */
267 	0x0,	/* unused */
268 	0x0,	/* unused */
269 	0x0,	/* unused */
270 	0x0,	/* unused */
271 	0x0,	/* unused */
272 };
273 
274 static int asyrsrv(queue_t *q);
275 static int asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr);
276 static int asyclose(queue_t *q, int flag, cred_t *credp);
277 static int asywputdo(queue_t *q, mblk_t *mp, boolean_t);
278 static int asywput(queue_t *q, mblk_t *mp);
279 
280 struct module_info asy_info = {
281 	0,
282 	"asy",
283 	0,
284 	INFPSZ,
285 	4096,
286 	128
287 };
288 
289 static struct qinit asy_rint = {
290 	putq,
291 	asyrsrv,
292 	asyopen,
293 	asyclose,
294 	NULL,
295 	&asy_info,
296 	NULL
297 };
298 
299 static struct qinit asy_wint = {
300 	asywput,
301 	NULL,
302 	NULL,
303 	NULL,
304 	NULL,
305 	&asy_info,
306 	NULL
307 };
308 
309 struct streamtab asy_str_info = {
310 	&asy_rint,
311 	&asy_wint,
312 	NULL,
313 	NULL
314 };
315 
316 static int asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
317 		void **result);
318 static int asyprobe(dev_info_t *);
319 static int asyattach(dev_info_t *, ddi_attach_cmd_t);
320 static int asydetach(dev_info_t *, ddi_detach_cmd_t);
321 static int asyquiesce(dev_info_t *);
322 
323 static 	struct cb_ops cb_asy_ops = {
324 	nodev,			/* cb_open */
325 	nodev,			/* cb_close */
326 	nodev,			/* cb_strategy */
327 	nodev,			/* cb_print */
328 	nodev,			/* cb_dump */
329 	nodev,			/* cb_read */
330 	nodev,			/* cb_write */
331 	nodev,			/* cb_ioctl */
332 	nodev,			/* cb_devmap */
333 	nodev,			/* cb_mmap */
334 	nodev,			/* cb_segmap */
335 	nochpoll,		/* cb_chpoll */
336 	ddi_prop_op,		/* cb_prop_op */
337 	&asy_str_info,		/* cb_stream */
338 	D_MP			/* cb_flag */
339 };
340 
341 struct dev_ops asy_ops = {
342 	DEVO_REV,		/* devo_rev */
343 	0,			/* devo_refcnt */
344 	asyinfo,		/* devo_getinfo */
345 	nulldev,		/* devo_identify */
346 	asyprobe,		/* devo_probe */
347 	asyattach,		/* devo_attach */
348 	asydetach,		/* devo_detach */
349 	nodev,			/* devo_reset */
350 	&cb_asy_ops,		/* devo_cb_ops */
351 	NULL,			/* devo_bus_ops */
352 	NULL,			/* power */
353 	asyquiesce,		/* quiesce */
354 };
355 
356 static struct modldrv modldrv = {
357 	&mod_driverops, /* Type of module.  This one is a driver */
358 	"ASY driver",
359 	&asy_ops,	/* driver ops */
360 };
361 
362 static struct modlinkage modlinkage = {
363 	MODREV_1,
364 	(void *)&modldrv,
365 	NULL
366 };
367 
368 int
369 _init(void)
370 {
371 	int i;
372 
373 	i = ddi_soft_state_init(&asy_soft_state, sizeof (struct asycom), 2);
374 	if (i == 0) {
375 		mutex_init(&asy_glob_lock, NULL, MUTEX_DRIVER, NULL);
376 		if ((i = mod_install(&modlinkage)) != 0) {
377 			mutex_destroy(&asy_glob_lock);
378 			ddi_soft_state_fini(&asy_soft_state);
379 		} else {
380 			DEBUGCONT2(ASY_DEBUG_INIT, "%s, debug = %x\n",
381 			    modldrv.drv_linkinfo, debug);
382 		}
383 	}
384 	return (i);
385 }
386 
387 int
388 _fini(void)
389 {
390 	int i;
391 
392 	if ((i = mod_remove(&modlinkage)) == 0) {
393 		DEBUGCONT1(ASY_DEBUG_INIT, "%s unloading\n",
394 		    modldrv.drv_linkinfo);
395 		ASSERT(max_asy_instance == -1);
396 		mutex_destroy(&asy_glob_lock);
397 		/* free "motherboard-serial-ports" property if allocated */
398 		if (com_ports != NULL && com_ports != (int *)standard_com_ports)
399 			ddi_prop_free(com_ports);
400 		com_ports = NULL;
401 		ddi_soft_state_fini(&asy_soft_state);
402 	}
403 	return (i);
404 }
405 
406 int
407 _info(struct modinfo *modinfop)
408 {
409 	return (mod_info(&modlinkage, modinfop));
410 }
411 
412 void
413 async_put_suspq(struct asycom *asy, mblk_t *mp)
414 {
415 	struct asyncline *async = asy->asy_priv;
416 
417 	ASSERT(mutex_owned(&asy->asy_excl));
418 
419 	if (async->async_suspqf == NULL)
420 		async->async_suspqf = mp;
421 	else
422 		async->async_suspqb->b_next = mp;
423 
424 	async->async_suspqb = mp;
425 }
426 
427 static mblk_t *
428 async_get_suspq(struct asycom *asy)
429 {
430 	struct asyncline *async = asy->asy_priv;
431 	mblk_t *mp;
432 
433 	ASSERT(mutex_owned(&asy->asy_excl));
434 
435 	if ((mp = async->async_suspqf) != NULL) {
436 		async->async_suspqf = mp->b_next;
437 		mp->b_next = NULL;
438 	} else {
439 		async->async_suspqb = NULL;
440 	}
441 	return (mp);
442 }
443 
444 static void
445 async_process_suspq(struct asycom *asy)
446 {
447 	struct asyncline *async = asy->asy_priv;
448 	mblk_t *mp;
449 
450 	ASSERT(mutex_owned(&asy->asy_excl));
451 
452 	while ((mp = async_get_suspq(asy)) != NULL) {
453 		queue_t *q;
454 
455 		q = async->async_ttycommon.t_writeq;
456 		ASSERT(q != NULL);
457 		mutex_exit(&asy->asy_excl);
458 		(void) asywputdo(q, mp, B_FALSE);
459 		mutex_enter(&asy->asy_excl);
460 	}
461 	async->async_flags &= ~ASYNC_DDI_SUSPENDED;
462 	cv_broadcast(&async->async_flags_cv);
463 }
464 
465 static int
466 asy_get_bus_type(dev_info_t *devinfo)
467 {
468 	char	parent_type[16];
469 	int	parentlen;
470 
471 	parentlen = sizeof (parent_type);
472 
473 	if (ddi_prop_op(DDI_DEV_T_ANY, devinfo, PROP_LEN_AND_VAL_BUF, 0,
474 	    "device_type", (caddr_t)parent_type, &parentlen)
475 	    != DDI_PROP_SUCCESS && ddi_prop_op(DDI_DEV_T_ANY, devinfo,
476 	    PROP_LEN_AND_VAL_BUF, 0, "bus-type", (caddr_t)parent_type,
477 	    &parentlen) != DDI_PROP_SUCCESS) {
478 			cmn_err(CE_WARN,
479 			    "asy: can't figure out device type for"
480 			    " parent \"%s\"",
481 			    ddi_get_name(ddi_get_parent(devinfo)));
482 			return (ASY_BUS_UNKNOWN);
483 	}
484 	if (strcmp(parent_type, "isa") == 0)
485 		return (ASY_BUS_ISA);
486 	else if (strcmp(parent_type, "pci") == 0)
487 		return (ASY_BUS_PCI);
488 	else
489 		return (ASY_BUS_UNKNOWN);
490 }
491 
492 static int
493 asy_get_io_regnum_pci(dev_info_t *devi, struct asycom *asy)
494 {
495 	int reglen, nregs;
496 	int regnum, i;
497 	uint64_t size;
498 	struct pci_phys_spec *reglist;
499 
500 	if (ddi_getlongprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS,
501 	    "reg", (caddr_t)&reglist, &reglen) != DDI_PROP_SUCCESS) {
502 		cmn_err(CE_WARN, "asy_get_io_regnum_pci: reg property"
503 		    " not found in devices property list");
504 		return (-1);
505 	}
506 
507 	/*
508 	 * PCI devices are assumed to not have broken FIFOs;
509 	 * Agere/Lucent Venus PCI modem chipsets are an example
510 	 */
511 	if (asy)
512 		asy->asy_flags2 |= ASY2_NO_LOOPBACK;
513 
514 	regnum = -1;
515 	nregs = reglen / sizeof (*reglist);
516 	for (i = 0; i < nregs; i++) {
517 		switch (reglist[i].pci_phys_hi & PCI_ADDR_MASK) {
518 		case PCI_ADDR_IO:		/* I/O bus reg property */
519 			if (regnum == -1) /* use only the first one */
520 				regnum = i;
521 			break;
522 
523 		default:
524 			break;
525 		}
526 	}
527 
528 	/* check for valid count of registers */
529 	if (regnum >= 0) {
530 		size = ((uint64_t)reglist[regnum].pci_size_low) |
531 		    ((uint64_t)reglist[regnum].pci_size_hi) << 32;
532 		if (size < 8)
533 			regnum = -1;
534 	}
535 	kmem_free(reglist, reglen);
536 	return (regnum);
537 }
538 
539 static int
540 asy_get_io_regnum_isa(dev_info_t *devi, struct asycom *asy)
541 {
542 	int reglen, nregs;
543 	int regnum, i;
544 	struct {
545 		uint_t bustype;
546 		int base;
547 		int size;
548 	} *reglist;
549 
550 	if (ddi_getlongprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS,
551 	    "reg", (caddr_t)&reglist, &reglen) != DDI_PROP_SUCCESS) {
552 		cmn_err(CE_WARN, "asy_get_io_regnum: reg property not found "
553 		    "in devices property list");
554 		return (-1);
555 	}
556 
557 	regnum = -1;
558 	nregs = reglen / sizeof (*reglist);
559 	for (i = 0; i < nregs; i++) {
560 		switch (reglist[i].bustype) {
561 		case 1:			/* I/O bus reg property */
562 			if (regnum == -1) /* only use the first one */
563 				regnum = i;
564 			break;
565 
566 		case pnpMTS0219:	/* Multitech MT5634ZTX modem */
567 			/* Venus chipset can't do loopback test */
568 			if (asy)
569 				asy->asy_flags2 |= ASY2_NO_LOOPBACK;
570 			break;
571 
572 		default:
573 			break;
574 		}
575 	}
576 
577 	/* check for valid count of registers */
578 	if ((regnum < 0) || (reglist[regnum].size < 8))
579 		regnum = -1;
580 	kmem_free(reglist, reglen);
581 	return (regnum);
582 }
583 
584 static int
585 asy_get_io_regnum(dev_info_t *devinfo, struct asycom *asy)
586 {
587 	switch (asy_get_bus_type(devinfo)) {
588 	case ASY_BUS_ISA:
589 		return (asy_get_io_regnum_isa(devinfo, asy));
590 	case ASY_BUS_PCI:
591 		return (asy_get_io_regnum_pci(devinfo, asy));
592 	default:
593 		return (-1);
594 	}
595 }
596 
597 static int
598 asydetach(dev_info_t *devi, ddi_detach_cmd_t cmd)
599 {
600 	int instance;
601 	struct asycom *asy;
602 	struct asyncline *async;
603 
604 	instance = ddi_get_instance(devi);	/* find out which unit */
605 
606 	asy = ddi_get_soft_state(asy_soft_state, instance);
607 	if (asy == NULL)
608 		return (DDI_FAILURE);
609 	async = asy->asy_priv;
610 
611 	switch (cmd) {
612 	case DDI_DETACH:
613 		DEBUGNOTE2(ASY_DEBUG_INIT, "asy%d: %s shutdown.",
614 		    instance, asy_hw_name(asy));
615 
616 		/* cancel DTR hold timeout */
617 		if (async->async_dtrtid != 0) {
618 			(void) untimeout(async->async_dtrtid);
619 			async->async_dtrtid = 0;
620 		}
621 
622 		/* remove all minor device node(s) for this device */
623 		ddi_remove_minor_node(devi, NULL);
624 
625 		mutex_destroy(&asy->asy_excl);
626 		mutex_destroy(&asy->asy_excl_hi);
627 		cv_destroy(&async->async_flags_cv);
628 		ddi_remove_intr(devi, 0, asy->asy_iblock);
629 		ddi_regs_map_free(&asy->asy_iohandle);
630 		ddi_remove_softintr(asy->asy_softintr_id);
631 		mutex_destroy(&asy->asy_soft_lock);
632 		asy_soft_state_free(asy);
633 		DEBUGNOTE1(ASY_DEBUG_INIT, "asy%d: shutdown complete",
634 		    instance);
635 		break;
636 	case DDI_SUSPEND:
637 		{
638 		unsigned i;
639 		uchar_t lsr;
640 
641 #ifdef	DEBUG
642 		if (asy_nosuspend)
643 			return (DDI_SUCCESS);
644 #endif
645 		mutex_enter(&asy->asy_excl);
646 
647 		ASSERT(async->async_ops >= 0);
648 		while (async->async_ops > 0)
649 			cv_wait(&async->async_ops_cv, &asy->asy_excl);
650 
651 		async->async_flags |= ASYNC_DDI_SUSPENDED;
652 
653 		/* Wait for timed break and delay to complete */
654 		while ((async->async_flags & (ASYNC_BREAK|ASYNC_DELAY))) {
655 			if (cv_wait_sig(&async->async_flags_cv, &asy->asy_excl)
656 			    == 0) {
657 				async_process_suspq(asy);
658 				mutex_exit(&asy->asy_excl);
659 				return (DDI_FAILURE);
660 			}
661 		}
662 
663 		/* Clear untimed break */
664 		if (async->async_flags & ASYNC_OUT_SUSPEND)
665 			async_resume_utbrk(async);
666 
667 		mutex_exit(&asy->asy_excl);
668 
669 		mutex_enter(&asy->asy_soft_sr);
670 		mutex_enter(&asy->asy_excl);
671 		if (async->async_wbufcid != 0) {
672 			bufcall_id_t bcid = async->async_wbufcid;
673 			async->async_wbufcid = 0;
674 			async->async_flags |= ASYNC_RESUME_BUFCALL;
675 			mutex_exit(&asy->asy_excl);
676 			unbufcall(bcid);
677 			mutex_enter(&asy->asy_excl);
678 		}
679 		mutex_enter(&asy->asy_excl_hi);
680 
681 		/* Disable interrupts from chip */
682 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
683 		asy->asy_flags |= ASY_DDI_SUSPENDED;
684 
685 		/*
686 		 * Hardware interrupts are disabled we can drop our high level
687 		 * lock and proceed.
688 		 */
689 		mutex_exit(&asy->asy_excl_hi);
690 
691 		/* Process remaining RX characters and RX errors, if any */
692 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
693 		async_rxint(asy, lsr);
694 
695 		/* Wait for TX to drain */
696 		for (i = 1000; i > 0; i--) {
697 			lsr = ddi_get8(asy->asy_iohandle,
698 			    asy->asy_ioaddr + LSR);
699 			if ((lsr & (XSRE | XHRE)) == (XSRE | XHRE))
700 				break;
701 			delay(drv_usectohz(10000));
702 		}
703 		if (i == 0)
704 			cmn_err(CE_WARN,
705 			    "asy: transmitter wasn't drained before "
706 			    "driver was suspended");
707 
708 		mutex_exit(&asy->asy_excl);
709 		mutex_exit(&asy->asy_soft_sr);
710 		break;
711 	}
712 	default:
713 		return (DDI_FAILURE);
714 	}
715 
716 	return (DDI_SUCCESS);
717 }
718 
719 /*
720  * asyprobe
721  * We don't bother probing for the hardware, as since Solaris 2.6, device
722  * nodes are only created for auto-detected hardware or nodes explicitly
723  * created by the user, e.g. via the DCA. However, we should check the
724  * device node is at least vaguely usable, i.e. we have a block of 8 i/o
725  * ports. This prevents attempting to attach to bogus serial ports which
726  * some BIOSs still partially report when they are disabled in the BIOS.
727  */
728 static int
729 asyprobe(dev_info_t *devi)
730 {
731 	return ((asy_get_io_regnum(devi, NULL) < 0) ?
732 	    DDI_PROBE_FAILURE : DDI_PROBE_DONTCARE);
733 }
734 
735 static int
736 asyattach(dev_info_t *devi, ddi_attach_cmd_t cmd)
737 {
738 	int instance;
739 	int mcr;
740 	int ret;
741 	int regnum = 0;
742 	int i;
743 	struct asycom *asy;
744 	char name[ASY_MINOR_LEN];
745 	int status;
746 	static ddi_device_acc_attr_t ioattr = {
747 		DDI_DEVICE_ATTR_V0,
748 		DDI_NEVERSWAP_ACC,
749 		DDI_STRICTORDER_ACC,
750 	};
751 
752 	instance = ddi_get_instance(devi);	/* find out which unit */
753 
754 	switch (cmd) {
755 	case DDI_ATTACH:
756 		break;
757 	case DDI_RESUME:
758 	{
759 		struct asyncline *async;
760 
761 #ifdef	DEBUG
762 		if (asy_nosuspend)
763 			return (DDI_SUCCESS);
764 #endif
765 		asy = ddi_get_soft_state(asy_soft_state, instance);
766 		if (asy == NULL)
767 			return (DDI_FAILURE);
768 
769 		mutex_enter(&asy->asy_soft_sr);
770 		mutex_enter(&asy->asy_excl);
771 		mutex_enter(&asy->asy_excl_hi);
772 
773 		async = asy->asy_priv;
774 		/* Disable interrupts */
775 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
776 		if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
777 			mutex_exit(&asy->asy_excl_hi);
778 			mutex_exit(&asy->asy_excl);
779 			mutex_exit(&asy->asy_soft_sr);
780 			cmn_err(CE_WARN, "!Cannot identify UART chip at %p\n",
781 			    (void *)asy->asy_ioaddr);
782 			return (DDI_FAILURE);
783 		}
784 		asy->asy_flags &= ~ASY_DDI_SUSPENDED;
785 		if (async->async_flags & ASYNC_ISOPEN) {
786 			asy_program(asy, ASY_INIT);
787 			/* Kick off output */
788 			if (async->async_ocnt > 0) {
789 				async_resume(async);
790 			} else {
791 				mutex_exit(&asy->asy_excl_hi);
792 				if (async->async_xmitblk)
793 					freeb(async->async_xmitblk);
794 				async->async_xmitblk = NULL;
795 				async_start(async);
796 				mutex_enter(&asy->asy_excl_hi);
797 			}
798 			ASYSETSOFT(asy);
799 		}
800 		mutex_exit(&asy->asy_excl_hi);
801 		mutex_exit(&asy->asy_excl);
802 		mutex_exit(&asy->asy_soft_sr);
803 
804 		mutex_enter(&asy->asy_excl);
805 		if (async->async_flags & ASYNC_RESUME_BUFCALL) {
806 			async->async_wbufcid = bufcall(async->async_wbufcds,
807 			    BPRI_HI, (void (*)(void *)) async_reioctl,
808 			    (void *)(intptr_t)async->async_common->asy_unit);
809 			async->async_flags &= ~ASYNC_RESUME_BUFCALL;
810 		}
811 		async_process_suspq(asy);
812 		mutex_exit(&asy->asy_excl);
813 		return (DDI_SUCCESS);
814 	}
815 	default:
816 		return (DDI_FAILURE);
817 	}
818 
819 	ret = ddi_soft_state_zalloc(asy_soft_state, instance);
820 	if (ret != DDI_SUCCESS)
821 		return (DDI_FAILURE);
822 	asy = ddi_get_soft_state(asy_soft_state, instance);
823 	ASSERT(asy != NULL);	/* can't fail - we only just allocated it */
824 	asy->asy_unit = instance;
825 	mutex_enter(&asy_glob_lock);
826 	if (instance > max_asy_instance)
827 		max_asy_instance = instance;
828 	mutex_exit(&asy_glob_lock);
829 
830 	regnum = asy_get_io_regnum(devi, asy);
831 
832 	if (regnum < 0 ||
833 	    ddi_regs_map_setup(devi, regnum, (caddr_t *)&asy->asy_ioaddr,
834 	    (offset_t)0, (offset_t)0, &ioattr, &asy->asy_iohandle)
835 	    != DDI_SUCCESS) {
836 		cmn_err(CE_WARN, "asy%d: could not map UART registers @ %p",
837 		    instance, (void *)asy->asy_ioaddr);
838 
839 		asy_soft_state_free(asy);
840 		return (DDI_FAILURE);
841 	}
842 
843 	DEBUGCONT2(ASY_DEBUG_INIT, "asy%dattach: UART @ %p\n",
844 	    instance, (void *)asy->asy_ioaddr);
845 
846 	mutex_enter(&asy_glob_lock);
847 	if (com_ports == NULL) {	/* need to initialize com_ports */
848 		if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, devi, 0,
849 		    "motherboard-serial-ports", &com_ports, &num_com_ports) !=
850 		    DDI_PROP_SUCCESS) {
851 			/* Use our built-in COM[1234] values */
852 			com_ports = (int *)standard_com_ports;
853 			num_com_ports = sizeof (standard_com_ports) /
854 			    sizeof (standard_com_ports[0]);
855 		}
856 		if (num_com_ports > 10) {
857 			/* We run out of single digits for device properties */
858 			num_com_ports = 10;
859 			cmn_err(CE_WARN,
860 			    "More than %d motherboard-serial-ports",
861 			    num_com_ports);
862 		}
863 	}
864 	mutex_exit(&asy_glob_lock);
865 
866 	/*
867 	 * Lookup the i/o address to see if this is a standard COM port
868 	 * in which case we assign it the correct tty[a-d] to match the
869 	 * COM port number, or some other i/o address in which case it
870 	 * will be assigned /dev/term/[0123...] in some rather arbitrary
871 	 * fashion.
872 	 */
873 
874 	for (i = 0; i < num_com_ports; i++) {
875 		if (asy->asy_ioaddr == (uint8_t *)(uintptr_t)com_ports[i]) {
876 			asy->asy_com_port = i + 1;
877 			break;
878 		}
879 	}
880 
881 	/*
882 	 * It appears that there was async hardware that on reset
883 	 * did not clear ICR.  Hence when we get to
884 	 * ddi_get_iblock_cookie below, this hardware would cause
885 	 * the system to hang if there was input available.
886 	 */
887 
888 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0x00);
889 
890 	/* establish default usage */
891 	asy->asy_mcr |= RTS|DTR;		/* do use RTS/DTR after open */
892 	asy->asy_lcr = STOP1|BITS8;		/* default to 1 stop 8 bits */
893 	asy->asy_bidx = B9600;			/* default to 9600  */
894 #ifdef DEBUG
895 	asy->asy_msint_cnt = 0;			/* # of times in async_msint */
896 #endif
897 	mcr = 0;				/* don't enable until open */
898 
899 	if (asy->asy_com_port != 0) {
900 		/*
901 		 * For motherboard ports, emulate tty eeprom properties.
902 		 * Actually, we can't tell if a port is motherboard or not,
903 		 * so for "motherboard ports", read standard DOS COM ports.
904 		 */
905 		switch (asy_getproperty(devi, asy, "ignore-cd")) {
906 		case 0:				/* *-ignore-cd=False */
907 			DEBUGCONT1(ASY_DEBUG_MODEM,
908 			    "asy%dattach: clear ASY_IGNORE_CD\n", instance);
909 			asy->asy_flags &= ~ASY_IGNORE_CD; /* wait for cd */
910 			break;
911 		case 1:				/* *-ignore-cd=True */
912 			/*FALLTHRU*/
913 		default:			/* *-ignore-cd not defined */
914 			/*
915 			 * We set rather silly defaults of soft carrier on
916 			 * and DTR/RTS raised here because it might be that
917 			 * one of the motherboard ports is the system console.
918 			 */
919 			DEBUGCONT1(ASY_DEBUG_MODEM,
920 			    "asy%dattach: set ASY_IGNORE_CD, set RTS & DTR\n",
921 			    instance);
922 			mcr = asy->asy_mcr;		/* rts/dtr on */
923 			asy->asy_flags |= ASY_IGNORE_CD;	/* ignore cd */
924 			break;
925 		}
926 
927 		/* Property for not raising DTR/RTS */
928 		switch (asy_getproperty(devi, asy, "rts-dtr-off")) {
929 		case 0:				/* *-rts-dtr-off=False */
930 			asy->asy_flags |= ASY_RTS_DTR_OFF;	/* OFF */
931 			mcr = asy->asy_mcr;		/* rts/dtr on */
932 			DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dattach: "
933 			    "ASY_RTS_DTR_OFF set and DTR & RTS set\n",
934 			    instance);
935 			break;
936 		case 1:				/* *-rts-dtr-off=True */
937 			/*FALLTHRU*/
938 		default:			/* *-rts-dtr-off undefined */
939 			break;
940 		}
941 
942 		/* Parse property for tty modes */
943 		asy_parse_mode(devi, asy);
944 	} else {
945 		DEBUGCONT1(ASY_DEBUG_MODEM,
946 		    "asy%dattach: clear ASY_IGNORE_CD, clear RTS & DTR\n",
947 		    instance);
948 		asy->asy_flags &= ~ASY_IGNORE_CD;	/* wait for cd */
949 	}
950 
951 	/*
952 	 * Initialize the port with default settings.
953 	 */
954 
955 	asy->asy_fifo_buf = 1;
956 	asy->asy_use_fifo = FIFO_OFF;
957 
958 	/*
959 	 * Get icookie for mutexes initialization
960 	 */
961 	if ((ddi_get_iblock_cookie(devi, 0, &asy->asy_iblock) !=
962 	    DDI_SUCCESS) ||
963 	    (ddi_get_soft_iblock_cookie(devi, DDI_SOFTINT_MED,
964 	    &asy->asy_soft_iblock) != DDI_SUCCESS)) {
965 		ddi_regs_map_free(&asy->asy_iohandle);
966 		cmn_err(CE_CONT,
967 		    "asy%d: could not hook interrupt for UART @ %p\n",
968 		    instance, (void *)asy->asy_ioaddr);
969 		asy_soft_state_free(asy);
970 		return (DDI_FAILURE);
971 	}
972 
973 	/*
974 	 * Initialize mutexes before accessing the hardware
975 	 */
976 	mutex_init(&asy->asy_soft_lock, NULL, MUTEX_DRIVER,
977 	    (void *)asy->asy_soft_iblock);
978 	mutex_init(&asy->asy_excl, NULL, MUTEX_DRIVER, NULL);
979 	mutex_init(&asy->asy_excl_hi, NULL, MUTEX_DRIVER,
980 	    (void *)asy->asy_iblock);
981 	mutex_init(&asy->asy_soft_sr, NULL, MUTEX_DRIVER,
982 	    (void *)asy->asy_soft_iblock);
983 	mutex_enter(&asy->asy_excl);
984 	mutex_enter(&asy->asy_excl_hi);
985 
986 	if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
987 		mutex_exit(&asy->asy_excl_hi);
988 		mutex_exit(&asy->asy_excl);
989 		mutex_destroy(&asy->asy_soft_lock);
990 		mutex_destroy(&asy->asy_excl);
991 		mutex_destroy(&asy->asy_excl_hi);
992 		mutex_destroy(&asy->asy_soft_sr);
993 		ddi_regs_map_free(&asy->asy_iohandle);
994 		cmn_err(CE_CONT, "!Cannot identify UART chip at %p\n",
995 		    (void *)asy->asy_ioaddr);
996 		asy_soft_state_free(asy);
997 		return (DDI_FAILURE);
998 	}
999 
1000 	/* disable all interrupts */
1001 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
1002 	/* select baud rate generator */
1003 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
1004 	/* Set the baud rate to 9600 */
1005 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLL),
1006 	    asyspdtab[asy->asy_bidx] & 0xff);
1007 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLH),
1008 	    (asyspdtab[asy->asy_bidx] >> 8) & 0xff);
1009 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, asy->asy_lcr);
1010 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1011 
1012 	mutex_exit(&asy->asy_excl_hi);
1013 	mutex_exit(&asy->asy_excl);
1014 
1015 	/*
1016 	 * Set up the other components of the asycom structure for this port.
1017 	 */
1018 	asy->asy_dip = devi;
1019 
1020 	/*
1021 	 * Install per instance software interrupt handler.
1022 	 */
1023 	if (ddi_add_softintr(devi, DDI_SOFTINT_MED,
1024 	    &(asy->asy_softintr_id), NULL, 0, asysoftintr,
1025 	    (caddr_t)asy) != DDI_SUCCESS) {
1026 		mutex_destroy(&asy->asy_soft_lock);
1027 		mutex_destroy(&asy->asy_excl);
1028 		mutex_destroy(&asy->asy_excl_hi);
1029 		ddi_regs_map_free(&asy->asy_iohandle);
1030 		cmn_err(CE_CONT,
1031 		    "Can not set soft interrupt for ASY driver\n");
1032 		asy_soft_state_free(asy);
1033 		return (DDI_FAILURE);
1034 	}
1035 
1036 	mutex_enter(&asy->asy_excl);
1037 	mutex_enter(&asy->asy_excl_hi);
1038 
1039 	/*
1040 	 * Install interrupt handler for this device.
1041 	 */
1042 	if (ddi_add_intr(devi, 0, NULL, 0, asyintr,
1043 	    (caddr_t)asy) != DDI_SUCCESS) {
1044 		mutex_exit(&asy->asy_excl_hi);
1045 		mutex_exit(&asy->asy_excl);
1046 		ddi_remove_softintr(asy->asy_softintr_id);
1047 		mutex_destroy(&asy->asy_soft_lock);
1048 		mutex_destroy(&asy->asy_excl);
1049 		mutex_destroy(&asy->asy_excl_hi);
1050 		ddi_regs_map_free(&asy->asy_iohandle);
1051 		cmn_err(CE_CONT,
1052 		    "Can not set device interrupt for ASY driver\n");
1053 		asy_soft_state_free(asy);
1054 		return (DDI_FAILURE);
1055 	}
1056 
1057 	mutex_exit(&asy->asy_excl_hi);
1058 	mutex_exit(&asy->asy_excl);
1059 
1060 	asyinit(asy);	/* initialize the asyncline structure */
1061 
1062 	/* create minor device nodes for this device */
1063 	if (asy->asy_com_port != 0) {
1064 		/*
1065 		 * For DOS COM ports, add letter suffix so
1066 		 * devfsadm can create correct link names.
1067 		 */
1068 		name[0] = asy->asy_com_port + 'a' - 1;
1069 		name[1] = '\0';
1070 	} else {
1071 		/*
1072 		 * asy port which isn't a standard DOS COM
1073 		 * port gets a numeric name based on instance
1074 		 */
1075 		(void) snprintf(name, ASY_MINOR_LEN, "%d", instance);
1076 	}
1077 	status = ddi_create_minor_node(devi, name, S_IFCHR, instance,
1078 	    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB : DDI_NT_SERIAL, NULL);
1079 	if (status == DDI_SUCCESS) {
1080 		(void) strcat(name, ",cu");
1081 		status = ddi_create_minor_node(devi, name, S_IFCHR,
1082 		    OUTLINE | instance,
1083 		    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB_DO :
1084 		    DDI_NT_SERIAL_DO, NULL);
1085 	}
1086 
1087 	if (status != DDI_SUCCESS) {
1088 		struct asyncline *async = asy->asy_priv;
1089 
1090 		ddi_remove_minor_node(devi, NULL);
1091 		ddi_remove_intr(devi, 0, asy->asy_iblock);
1092 		ddi_remove_softintr(asy->asy_softintr_id);
1093 		mutex_destroy(&asy->asy_soft_lock);
1094 		mutex_destroy(&asy->asy_excl);
1095 		mutex_destroy(&asy->asy_excl_hi);
1096 		cv_destroy(&async->async_flags_cv);
1097 		ddi_regs_map_free(&asy->asy_iohandle);
1098 		asy_soft_state_free(asy);
1099 		return (DDI_FAILURE);
1100 	}
1101 
1102 	/*
1103 	 * Fill in the polled I/O structure.
1104 	 */
1105 	asy->polledio.cons_polledio_version = CONSPOLLEDIO_V0;
1106 	asy->polledio.cons_polledio_argument = (cons_polledio_arg_t)asy;
1107 	asy->polledio.cons_polledio_putchar = asyputchar;
1108 	asy->polledio.cons_polledio_getchar = asygetchar;
1109 	asy->polledio.cons_polledio_ischar = asyischar;
1110 	asy->polledio.cons_polledio_enter = NULL;
1111 	asy->polledio.cons_polledio_exit = NULL;
1112 
1113 	ddi_report_dev(devi);
1114 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dattach: done\n", instance);
1115 	return (DDI_SUCCESS);
1116 }
1117 
1118 /*ARGSUSED*/
1119 static int
1120 asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
1121 	void **result)
1122 {
1123 	dev_t dev = (dev_t)arg;
1124 	int instance, error;
1125 	struct asycom *asy;
1126 
1127 	instance = UNIT(dev);
1128 
1129 	switch (infocmd) {
1130 	case DDI_INFO_DEVT2DEVINFO:
1131 		asy = ddi_get_soft_state(asy_soft_state, instance);
1132 		if ((asy == NULL) || (asy->asy_dip == NULL))
1133 			error = DDI_FAILURE;
1134 		else {
1135 			*result = (void *) asy->asy_dip;
1136 			error = DDI_SUCCESS;
1137 		}
1138 		break;
1139 	case DDI_INFO_DEVT2INSTANCE:
1140 		*result = (void *)(intptr_t)instance;
1141 		error = DDI_SUCCESS;
1142 		break;
1143 	default:
1144 		error = DDI_FAILURE;
1145 	}
1146 	return (error);
1147 }
1148 
1149 /* asy_getproperty -- walk through all name variants until we find a match */
1150 
1151 static int
1152 asy_getproperty(dev_info_t *devi, struct asycom *asy, const char *property)
1153 {
1154 	int len;
1155 	int ret;
1156 	char letter = asy->asy_com_port + 'a' - 1;	/* for ttya */
1157 	char number = asy->asy_com_port + '0';		/* for COM1 */
1158 	char val[40];
1159 	char name[40];
1160 
1161 	/* Property for ignoring DCD */
1162 	(void) sprintf(name, "tty%c-%s", letter, property);
1163 	len = sizeof (val);
1164 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1165 	if (ret != DDI_PROP_SUCCESS) {
1166 		(void) sprintf(name, "com%c-%s", number, property);
1167 		len = sizeof (val);
1168 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1169 	}
1170 	if (ret != DDI_PROP_SUCCESS) {
1171 		(void) sprintf(name, "tty0%c-%s", number, property);
1172 		len = sizeof (val);
1173 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1174 	}
1175 	if (ret != DDI_PROP_SUCCESS) {
1176 		(void) sprintf(name, "port-%c-%s", letter, property);
1177 		len = sizeof (val);
1178 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1179 	}
1180 	if (ret != DDI_PROP_SUCCESS)
1181 		return (-1);		/* property non-existant */
1182 	if (val[0] == 'f' || val[0] == 'F' || val[0] == '0')
1183 		return (0);		/* property false/0 */
1184 	return (1);			/* property true/!0 */
1185 }
1186 
1187 /* asy_soft_state_free - local wrapper for ddi_soft_state_free(9F) */
1188 
1189 static void
1190 asy_soft_state_free(struct asycom *asy)
1191 {
1192 	mutex_enter(&asy_glob_lock);
1193 	/* If we were the max_asy_instance, work out new value */
1194 	if (asy->asy_unit == max_asy_instance) {
1195 		while (--max_asy_instance >= 0) {
1196 			if (ddi_get_soft_state(asy_soft_state,
1197 			    max_asy_instance) != NULL)
1198 				break;
1199 		}
1200 	}
1201 	mutex_exit(&asy_glob_lock);
1202 
1203 	if (asy->asy_priv != NULL) {
1204 		kmem_free(asy->asy_priv, sizeof (struct asyncline));
1205 		asy->asy_priv = NULL;
1206 	}
1207 	ddi_soft_state_free(asy_soft_state, asy->asy_unit);
1208 }
1209 
1210 static char *
1211 asy_hw_name(struct asycom *asy)
1212 {
1213 	switch (asy->asy_hwtype) {
1214 	case ASY8250A:
1215 		return ("8250A/16450");
1216 	case ASY16550:
1217 		return ("16550");
1218 	case ASY16550A:
1219 		return ("16550A");
1220 	case ASY16650:
1221 		return ("16650");
1222 	case ASY16750:
1223 		return ("16750");
1224 	default:
1225 		DEBUGNOTE2(ASY_DEBUG_INIT,
1226 		    "asy%d: asy_hw_name: unknown asy_hwtype: %d",
1227 		    asy->asy_unit, asy->asy_hwtype);
1228 		return ("?");
1229 	}
1230 }
1231 
1232 static int
1233 asy_identify_chip(dev_info_t *devi, struct asycom *asy)
1234 {
1235 	int ret;
1236 	int mcr;
1237 	dev_t dev;
1238 	uint_t hwtype;
1239 
1240 	if (asy_scr_test) {
1241 		/* Check scratch register works. */
1242 
1243 		/* write to scratch register */
1244 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, SCRTEST);
1245 		/* make sure that pattern doesn't just linger on the bus */
1246 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR, 0x00);
1247 		/* read data back from scratch register */
1248 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1249 		if (ret != SCRTEST) {
1250 			/*
1251 			 * Scratch register not working.
1252 			 * Probably not an async chip.
1253 			 * 8250 and 8250B don't have scratch registers,
1254 			 * but only worked in ancient PC XT's anyway.
1255 			 */
1256 			cmn_err(CE_CONT, "!asy%d: UART @ %p "
1257 			    "scratch register: expected 0x5a, got 0x%02x\n",
1258 			    asy->asy_unit, (void *)asy->asy_ioaddr, ret);
1259 			return (DDI_FAILURE);
1260 		}
1261 	}
1262 	/*
1263 	 * Use 16550 fifo reset sequence specified in NS application
1264 	 * note. Disable fifos until chip is initialized.
1265 	 */
1266 	ddi_put8(asy->asy_iohandle,
1267 	    asy->asy_ioaddr + FIFOR, 0x00);	/* clear */
1268 	ddi_put8(asy->asy_iohandle,
1269 	    asy->asy_ioaddr + FIFOR, FIFO_ON);	/* enable */
1270 	ddi_put8(asy->asy_iohandle,
1271 	    asy->asy_ioaddr + FIFOR, FIFO_ON | FIFORXFLSH);
1272 						/* reset */
1273 	if (asymaxchip >= ASY16650 && asy_scr_test) {
1274 		/*
1275 		 * Reset 16650 enhanced regs also, in case we have one of these
1276 		 */
1277 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1278 		    EFRACCESS);
1279 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1280 		    0);
1281 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1282 		    STOP1|BITS8);
1283 	}
1284 
1285 	/*
1286 	 * See what sort of FIFO we have.
1287 	 * Try enabling it and see what chip makes of this.
1288 	 */
1289 
1290 	asy->asy_fifor = 0;
1291 	asy->asy_hwtype = asymaxchip; /* just for asy_reset_fifo() */
1292 	if (asymaxchip >= ASY16550A)
1293 		asy->asy_fifor |=
1294 		    FIFO_ON | FIFODMA | (asy_trig_level & 0xff);
1295 	if (asymaxchip >= ASY16650)
1296 		asy->asy_fifor |= FIFOEXTRA1 | FIFOEXTRA2;
1297 
1298 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1299 
1300 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1301 	ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
1302 	DEBUGCONT4(ASY_DEBUG_CHIP,
1303 	    "asy%d: probe fifo FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1304 	    asy->asy_unit, asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH,
1305 	    ret, mcr);
1306 	switch (ret & 0xf0) {
1307 	case 0x40:
1308 		hwtype = ASY16550; /* 16550 with broken FIFO */
1309 		asy->asy_fifor = 0;
1310 		break;
1311 	case 0xc0:
1312 		hwtype = ASY16550A;
1313 		asy->asy_fifo_buf = 16;
1314 		asy->asy_use_fifo = FIFO_ON;
1315 		asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1316 		break;
1317 	case 0xe0:
1318 		hwtype = ASY16650;
1319 		asy->asy_fifo_buf = 32;
1320 		asy->asy_use_fifo = FIFO_ON;
1321 		asy->asy_fifor &= ~(FIFOEXTRA1);
1322 		break;
1323 	case 0xf0:
1324 		/*
1325 		 * Note we get 0xff if chip didn't return us anything,
1326 		 * e.g. if there's no chip there.
1327 		 */
1328 		if (ret == 0xff) {
1329 			cmn_err(CE_CONT, "asy%d: UART @ %p "
1330 			    "interrupt register: got 0xff\n",
1331 			    asy->asy_unit, (void *)asy->asy_ioaddr);
1332 			return (DDI_FAILURE);
1333 		}
1334 		/*FALLTHRU*/
1335 	case 0xd0:
1336 		hwtype = ASY16750;
1337 		asy->asy_fifo_buf = 64;
1338 		asy->asy_use_fifo = FIFO_ON;
1339 		break;
1340 	default:
1341 		hwtype = ASY8250A; /* No FIFO */
1342 		asy->asy_fifor = 0;
1343 	}
1344 
1345 	if (hwtype > asymaxchip) {
1346 		cmn_err(CE_CONT, "asy%d: UART @ %p "
1347 		    "unexpected probe result: "
1348 		    "FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1349 		    asy->asy_unit, (void *)asy->asy_ioaddr,
1350 		    asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH, ret, mcr);
1351 		return (DDI_FAILURE);
1352 	}
1353 
1354 	/*
1355 	 * Now reset the FIFO operation appropriate for the chip type.
1356 	 * Note we must call asy_reset_fifo() before any possible
1357 	 * downgrade of the asy->asy_hwtype, or it may not disable
1358 	 * the more advanced features we specifically want downgraded.
1359 	 */
1360 	asy_reset_fifo(asy, 0);
1361 	asy->asy_hwtype = hwtype;
1362 
1363 	/*
1364 	 * Check for Exar/Startech ST16C650, which will still look like a
1365 	 * 16550A until we enable its enhanced mode.
1366 	 */
1367 	if (asy->asy_hwtype == ASY16550A && asymaxchip >= ASY16650 &&
1368 	    asy_scr_test) {
1369 		/* Enable enhanced mode register access */
1370 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1371 		    EFRACCESS);
1372 		/* zero scratch register (not scratch register if enhanced) */
1373 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, 0);
1374 		/* Disable enhanced mode register access */
1375 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1376 		    STOP1|BITS8);
1377 		/* read back scratch register */
1378 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1379 		if (ret == SCRTEST) {
1380 			/* looks like we have an ST16650 -- enable it */
1381 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1382 			    EFRACCESS);
1383 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1384 			    ENHENABLE);
1385 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1386 			    STOP1|BITS8);
1387 			asy->asy_hwtype = ASY16650;
1388 			asy->asy_fifo_buf = 32;
1389 			asy->asy_fifor |= 0x10; /* 24 byte txfifo trigger */
1390 			asy_reset_fifo(asy, 0);
1391 		}
1392 	}
1393 
1394 	/*
1395 	 * If we think we might have a FIFO larger than 16 characters,
1396 	 * measure FIFO size and check it against expected.
1397 	 */
1398 	if (asy_fifo_test > 0 &&
1399 	    !(asy->asy_flags2 & ASY2_NO_LOOPBACK) &&
1400 	    (asy->asy_fifo_buf > 16 ||
1401 	    (asy_fifo_test > 1 && asy->asy_use_fifo == FIFO_ON) ||
1402 	    ASY_DEBUG(ASY_DEBUG_CHIP))) {
1403 		int i;
1404 
1405 		/* Set baud rate to 57600 (fairly arbitrary choice) */
1406 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1407 		    DLAB);
1408 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
1409 		    asyspdtab[B57600] & 0xff);
1410 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1411 		    (asyspdtab[B57600] >> 8) & 0xff);
1412 		/* Set 8 bits, 1 stop bit */
1413 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1414 		    STOP1|BITS8);
1415 		/* Set loopback mode */
1416 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1417 		    DTR | RTS | ASY_LOOP | OUT1 | OUT2);
1418 
1419 		/* Overfill fifo */
1420 		for (i = 0; i < asy->asy_fifo_buf * 2; i++) {
1421 			ddi_put8(asy->asy_iohandle,
1422 			    asy->asy_ioaddr + DAT, i);
1423 		}
1424 		/*
1425 		 * Now there's an interesting question here about which
1426 		 * FIFO we're testing the size of, RX or TX. We just
1427 		 * filled the TX FIFO much faster than it can empty,
1428 		 * although it is possible one or two characters may
1429 		 * have gone from it to the TX shift register.
1430 		 * We wait for enough time for all the characters to
1431 		 * move into the RX FIFO and any excess characters to
1432 		 * have been lost, and then read all the RX FIFO. So
1433 		 * the answer we finally get will be the size which is
1434 		 * the MIN(RX FIFO,(TX FIFO + 1 or 2)). The critical
1435 		 * one is actually the TX FIFO, because if we overfill
1436 		 * it in normal operation, the excess characters are
1437 		 * lost with no warning.
1438 		 */
1439 		/*
1440 		 * Wait for characters to move into RX FIFO.
1441 		 * In theory, 200 * asy->asy_fifo_buf * 2 should be
1442 		 * enough. However, in practice it isn't always, so we
1443 		 * increase to 400 so some slow 16550A's finish, and we
1444 		 * increase to 3 so we spot more characters coming back
1445 		 * than we sent, in case that should ever happen.
1446 		 */
1447 		delay(drv_usectohz(400 * asy->asy_fifo_buf * 3));
1448 
1449 		/* Now see how many characters we can read back */
1450 		for (i = 0; i < asy->asy_fifo_buf * 3; i++) {
1451 			ret = ddi_get8(asy->asy_iohandle,
1452 			    asy->asy_ioaddr + LSR);
1453 			if (!(ret & RCA))
1454 				break;	/* FIFO emptied */
1455 			(void) ddi_get8(asy->asy_iohandle,
1456 			    asy->asy_ioaddr + DAT); /* lose another */
1457 		}
1458 
1459 		DEBUGCONT3(ASY_DEBUG_CHIP,
1460 		    "asy%d FIFO size: expected=%d, measured=%d\n",
1461 		    asy->asy_unit, asy->asy_fifo_buf, i);
1462 
1463 		hwtype = asy->asy_hwtype;
1464 		if (i < asy->asy_fifo_buf) {
1465 			/*
1466 			 * FIFO is somewhat smaller than we anticipated.
1467 			 * If we have 16 characters usable, then this
1468 			 * UART will probably work well enough in
1469 			 * 16550A mode. If less than 16 characters,
1470 			 * then we'd better not use it at all.
1471 			 * UARTs with busted FIFOs do crop up.
1472 			 */
1473 			if (i >= 16 && asy->asy_fifo_buf >= 16) {
1474 				/* fall back to a 16550A */
1475 				hwtype = ASY16550A;
1476 				asy->asy_fifo_buf = 16;
1477 				asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1478 			} else {
1479 				/* fall back to no FIFO at all */
1480 				hwtype = ASY16550;
1481 				asy->asy_fifo_buf = 1;
1482 				asy->asy_use_fifo = FIFO_OFF;
1483 				asy->asy_fifor &=
1484 				    ~(FIFO_ON | FIFOEXTRA1 | FIFOEXTRA2);
1485 			}
1486 		}
1487 		/*
1488 		 * We will need to reprogram the FIFO if we changed
1489 		 * our mind about how to drive it above, and in any
1490 		 * case, it would be a good idea to flush any garbage
1491 		 * out incase the loopback test left anything behind.
1492 		 * Again as earlier above, we must call asy_reset_fifo()
1493 		 * before any possible downgrade of asy->asy_hwtype.
1494 		 */
1495 		if (asy->asy_hwtype >= ASY16650 && hwtype < ASY16650) {
1496 			/* Disable 16650 enhanced mode */
1497 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1498 			    EFRACCESS);
1499 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1500 			    0);
1501 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1502 			    STOP1|BITS8);
1503 		}
1504 		asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1505 		asy->asy_hwtype = hwtype;
1506 
1507 		/* Clear loopback mode and restore DTR/RTS */
1508 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1509 	}
1510 
1511 	DEBUGNOTE3(ASY_DEBUG_CHIP, "asy%d %s @ %p",
1512 	    asy->asy_unit, asy_hw_name(asy), (void *)asy->asy_ioaddr);
1513 
1514 	/* Make UART type visible in device tree for prtconf, etc */
1515 	dev = makedevice(DDI_MAJOR_T_UNKNOWN, asy->asy_unit);
1516 	(void) ddi_prop_update_string(dev, devi, "uart", asy_hw_name(asy));
1517 
1518 	if (asy->asy_hwtype == ASY16550)	/* for broken 16550's, */
1519 		asy->asy_hwtype = ASY8250A;	/* drive them as 8250A */
1520 
1521 	return (DDI_SUCCESS);
1522 }
1523 
1524 /*
1525  * asyinit() initializes the TTY protocol-private data for this channel
1526  * before enabling the interrupts.
1527  */
1528 static void
1529 asyinit(struct asycom *asy)
1530 {
1531 	struct asyncline *async;
1532 
1533 	asy->asy_priv = kmem_zalloc(sizeof (struct asyncline), KM_SLEEP);
1534 	async = asy->asy_priv;
1535 	mutex_enter(&asy->asy_excl);
1536 	async->async_common = asy;
1537 	cv_init(&async->async_flags_cv, NULL, CV_DRIVER, NULL);
1538 	mutex_exit(&asy->asy_excl);
1539 }
1540 
1541 /*ARGSUSED3*/
1542 static int
1543 asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr)
1544 {
1545 	struct asycom	*asy;
1546 	struct asyncline *async;
1547 	int		mcr;
1548 	int		unit;
1549 	int 		len;
1550 	struct termios 	*termiosp;
1551 
1552 	unit = UNIT(*dev);
1553 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dopen\n", unit);
1554 	asy = ddi_get_soft_state(asy_soft_state, unit);
1555 	if (asy == NULL)
1556 		return (ENXIO);		/* unit not configured */
1557 	async = asy->asy_priv;
1558 	mutex_enter(&asy->asy_excl);
1559 
1560 again:
1561 	mutex_enter(&asy->asy_excl_hi);
1562 
1563 	/*
1564 	 * Block waiting for carrier to come up, unless this is a no-delay open.
1565 	 */
1566 	if (!(async->async_flags & ASYNC_ISOPEN)) {
1567 		/*
1568 		 * Set the default termios settings (cflag).
1569 		 * Others are set in ldterm.
1570 		 */
1571 		mutex_exit(&asy->asy_excl_hi);
1572 
1573 		if (ddi_getlongprop(DDI_DEV_T_ANY, ddi_root_node(),
1574 		    0, "ttymodes",
1575 		    (caddr_t)&termiosp, &len) == DDI_PROP_SUCCESS &&
1576 		    len == sizeof (struct termios)) {
1577 			async->async_ttycommon.t_cflag = termiosp->c_cflag;
1578 			kmem_free(termiosp, len);
1579 		} else
1580 			cmn_err(CE_WARN,
1581 			    "asy: couldn't get ttymodes property!");
1582 		mutex_enter(&asy->asy_excl_hi);
1583 
1584 		/* eeprom mode support - respect properties */
1585 		if (asy->asy_cflag)
1586 			async->async_ttycommon.t_cflag = asy->asy_cflag;
1587 
1588 		async->async_ttycommon.t_iflag = 0;
1589 		async->async_ttycommon.t_iocpending = NULL;
1590 		async->async_ttycommon.t_size.ws_row = 0;
1591 		async->async_ttycommon.t_size.ws_col = 0;
1592 		async->async_ttycommon.t_size.ws_xpixel = 0;
1593 		async->async_ttycommon.t_size.ws_ypixel = 0;
1594 		async->async_dev = *dev;
1595 		async->async_wbufcid = 0;
1596 
1597 		async->async_startc = CSTART;
1598 		async->async_stopc = CSTOP;
1599 		asy_program(asy, ASY_INIT);
1600 	} else
1601 		if ((async->async_ttycommon.t_flags & TS_XCLUDE) &&
1602 		    secpolicy_excl_open(cr) != 0) {
1603 		mutex_exit(&asy->asy_excl_hi);
1604 		mutex_exit(&asy->asy_excl);
1605 		return (EBUSY);
1606 	} else if ((*dev & OUTLINE) && !(async->async_flags & ASYNC_OUT)) {
1607 		mutex_exit(&asy->asy_excl_hi);
1608 		mutex_exit(&asy->asy_excl);
1609 		return (EBUSY);
1610 	}
1611 
1612 	if (*dev & OUTLINE)
1613 		async->async_flags |= ASYNC_OUT;
1614 
1615 	/* Raise DTR on every open, but delay if it was just lowered. */
1616 	while (async->async_flags & ASYNC_DTR_DELAY) {
1617 		DEBUGCONT1(ASY_DEBUG_MODEM,
1618 		    "asy%dopen: waiting for the ASYNC_DTR_DELAY to be clear\n",
1619 		    unit);
1620 		mutex_exit(&asy->asy_excl_hi);
1621 		if (cv_wait_sig(&async->async_flags_cv,
1622 		    &asy->asy_excl) == 0) {
1623 			DEBUGCONT1(ASY_DEBUG_MODEM,
1624 			    "asy%dopen: interrupted by signal, exiting\n",
1625 			    unit);
1626 			mutex_exit(&asy->asy_excl);
1627 			return (EINTR);
1628 		}
1629 		mutex_enter(&asy->asy_excl_hi);
1630 	}
1631 
1632 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1633 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1634 	    mcr|(asy->asy_mcr&DTR));
1635 
1636 	DEBUGCONT3(ASY_DEBUG_INIT,
1637 	    "asy%dopen: \"Raise DTR on every open\": make mcr = %x, "
1638 	    "make TS_SOFTCAR = %s\n",
1639 	    unit, mcr|(asy->asy_mcr&DTR),
1640 	    (asy->asy_flags & ASY_IGNORE_CD) ? "ON" : "OFF");
1641 
1642 	if (asy->asy_flags & ASY_IGNORE_CD) {
1643 		DEBUGCONT1(ASY_DEBUG_MODEM,
1644 		    "asy%dopen: ASY_IGNORE_CD set, set TS_SOFTCAR\n",
1645 		    unit);
1646 		async->async_ttycommon.t_flags |= TS_SOFTCAR;
1647 	}
1648 	else
1649 		async->async_ttycommon.t_flags &= ~TS_SOFTCAR;
1650 
1651 	/*
1652 	 * Check carrier.
1653 	 */
1654 	asy->asy_msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
1655 	DEBUGCONT3(ASY_DEBUG_INIT, "asy%dopen: TS_SOFTCAR is %s, "
1656 	    "MSR & DCD is %s\n",
1657 	    unit,
1658 	    (async->async_ttycommon.t_flags & TS_SOFTCAR) ? "set" : "clear",
1659 	    (asy->asy_msr & DCD) ? "set" : "clear");
1660 
1661 	if (asy->asy_msr & DCD)
1662 		async->async_flags |= ASYNC_CARR_ON;
1663 	else
1664 		async->async_flags &= ~ASYNC_CARR_ON;
1665 	mutex_exit(&asy->asy_excl_hi);
1666 
1667 	/*
1668 	 * If FNDELAY and FNONBLOCK are clear, block until carrier up.
1669 	 * Quit on interrupt.
1670 	 */
1671 	if (!(flag & (FNDELAY|FNONBLOCK)) &&
1672 	    !(async->async_ttycommon.t_cflag & CLOCAL)) {
1673 		if ((!(async->async_flags & (ASYNC_CARR_ON|ASYNC_OUT)) &&
1674 		    !(async->async_ttycommon.t_flags & TS_SOFTCAR)) ||
1675 		    ((async->async_flags & ASYNC_OUT) &&
1676 		    !(*dev & OUTLINE))) {
1677 			async->async_flags |= ASYNC_WOPEN;
1678 			if (cv_wait_sig(&async->async_flags_cv,
1679 			    &asy->asy_excl) == B_FALSE) {
1680 				async->async_flags &= ~ASYNC_WOPEN;
1681 				mutex_exit(&asy->asy_excl);
1682 				return (EINTR);
1683 			}
1684 			async->async_flags &= ~ASYNC_WOPEN;
1685 			goto again;
1686 		}
1687 	} else if ((async->async_flags & ASYNC_OUT) && !(*dev & OUTLINE)) {
1688 		mutex_exit(&asy->asy_excl);
1689 		return (EBUSY);
1690 	}
1691 
1692 	async->async_ttycommon.t_readq = rq;
1693 	async->async_ttycommon.t_writeq = WR(rq);
1694 	rq->q_ptr = WR(rq)->q_ptr = (caddr_t)async;
1695 	mutex_exit(&asy->asy_excl);
1696 	/*
1697 	 * Caution here -- qprocson sets the pointers that are used by canput
1698 	 * called by async_softint.  ASYNC_ISOPEN must *not* be set until those
1699 	 * pointers are valid.
1700 	 */
1701 	qprocson(rq);
1702 	async->async_flags |= ASYNC_ISOPEN;
1703 	async->async_polltid = 0;
1704 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dopen: done\n", unit);
1705 	return (0);
1706 }
1707 
1708 static void
1709 async_progress_check(void *arg)
1710 {
1711 	struct asyncline *async = arg;
1712 	struct asycom	 *asy = async->async_common;
1713 	mblk_t *bp;
1714 
1715 	/*
1716 	 * We define "progress" as either waiting on a timed break or delay, or
1717 	 * having had at least one transmitter interrupt.  If none of these are
1718 	 * true, then just terminate the output and wake up that close thread.
1719 	 */
1720 	mutex_enter(&asy->asy_excl);
1721 	mutex_enter(&asy->asy_excl_hi);
1722 	if (!(async->async_flags & (ASYNC_BREAK|ASYNC_DELAY|ASYNC_PROGRESS))) {
1723 		async->async_ocnt = 0;
1724 		async->async_flags &= ~ASYNC_BUSY;
1725 		async->async_timer = 0;
1726 		bp = async->async_xmitblk;
1727 		async->async_xmitblk = NULL;
1728 		mutex_exit(&asy->asy_excl_hi);
1729 		if (bp != NULL)
1730 			freeb(bp);
1731 		/*
1732 		 * Since this timer is running, we know that we're in exit(2).
1733 		 * That means that the user can't possibly be waiting on any
1734 		 * valid ioctl(2) completion anymore, and we should just flush
1735 		 * everything.
1736 		 */
1737 		flushq(async->async_ttycommon.t_writeq, FLUSHALL);
1738 		cv_broadcast(&async->async_flags_cv);
1739 	} else {
1740 		async->async_flags &= ~ASYNC_PROGRESS;
1741 		async->async_timer = timeout(async_progress_check, async,
1742 		    drv_usectohz(asy_drain_check));
1743 		mutex_exit(&asy->asy_excl_hi);
1744 	}
1745 	mutex_exit(&asy->asy_excl);
1746 }
1747 
1748 /*
1749  * Release DTR so that asyopen() can raise it.
1750  */
1751 static void
1752 async_dtr_free(struct asyncline *async)
1753 {
1754 	struct asycom *asy = async->async_common;
1755 
1756 	DEBUGCONT0(ASY_DEBUG_MODEM,
1757 	    "async_dtr_free, clearing ASYNC_DTR_DELAY\n");
1758 	mutex_enter(&asy->asy_excl);
1759 	async->async_flags &= ~ASYNC_DTR_DELAY;
1760 	async->async_dtrtid = 0;
1761 	cv_broadcast(&async->async_flags_cv);
1762 	mutex_exit(&asy->asy_excl);
1763 }
1764 
1765 /*
1766  * Close routine.
1767  */
1768 /*ARGSUSED2*/
1769 static int
1770 asyclose(queue_t *q, int flag, cred_t *credp)
1771 {
1772 	struct asyncline *async;
1773 	struct asycom	 *asy;
1774 	int icr, lcr;
1775 #ifdef DEBUG
1776 	int instance;
1777 #endif
1778 
1779 	async = (struct asyncline *)q->q_ptr;
1780 	ASSERT(async != NULL);
1781 #ifdef DEBUG
1782 	instance = UNIT(async->async_dev);
1783 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose\n", instance);
1784 #endif
1785 	asy = async->async_common;
1786 
1787 	mutex_enter(&asy->asy_excl);
1788 	async->async_flags |= ASYNC_CLOSING;
1789 
1790 	/*
1791 	 * Turn off PPS handling early to avoid events occuring during
1792 	 * close.  Also reset the DCD edge monitoring bit.
1793 	 */
1794 	mutex_enter(&asy->asy_excl_hi);
1795 	asy->asy_flags &= ~(ASY_PPS | ASY_PPS_EDGE);
1796 	mutex_exit(&asy->asy_excl_hi);
1797 
1798 	/*
1799 	 * There are two flavors of break -- timed (M_BREAK or TCSBRK) and
1800 	 * untimed (TIOCSBRK).  For the timed case, these are enqueued on our
1801 	 * write queue and there's a timer running, so we don't have to worry
1802 	 * about them.  For the untimed case, though, the user obviously made a
1803 	 * mistake, because these are handled immediately.  We'll terminate the
1804 	 * break now and honor his implicit request by discarding the rest of
1805 	 * the data.
1806 	 */
1807 	if (async->async_flags & ASYNC_OUT_SUSPEND) {
1808 		if (async->async_utbrktid != 0) {
1809 			(void) untimeout(async->async_utbrktid);
1810 			async->async_utbrktid = 0;
1811 		}
1812 		mutex_enter(&asy->asy_excl_hi);
1813 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1814 		ddi_put8(asy->asy_iohandle,
1815 		    asy->asy_ioaddr + LCR, (lcr & ~SETBREAK));
1816 		mutex_exit(&asy->asy_excl_hi);
1817 		async->async_flags &= ~ASYNC_OUT_SUSPEND;
1818 		goto nodrain;
1819 	}
1820 
1821 	/*
1822 	 * If the user told us not to delay the close ("non-blocking"), then
1823 	 * don't bother trying to drain.
1824 	 *
1825 	 * If the user did M_STOP (ASYNC_STOPPED), there's no hope of ever
1826 	 * getting an M_START (since these messages aren't enqueued), and the
1827 	 * only other way to clear the stop condition is by loss of DCD, which
1828 	 * would discard the queue data.  Thus, we drop the output data if
1829 	 * ASYNC_STOPPED is set.
1830 	 */
1831 	if ((flag & (FNDELAY|FNONBLOCK)) ||
1832 	    (async->async_flags & ASYNC_STOPPED)) {
1833 		goto nodrain;
1834 	}
1835 
1836 	/*
1837 	 * If there's any pending output, then we have to try to drain it.
1838 	 * There are two main cases to be handled:
1839 	 *	- called by close(2): need to drain until done or until
1840 	 *	  a signal is received.  No timeout.
1841 	 *	- called by exit(2): need to drain while making progress
1842 	 *	  or until a timeout occurs.  No signals.
1843 	 *
1844 	 * If we can't rely on receiving a signal to get us out of a hung
1845 	 * session, then we have to use a timer.  In this case, we set a timer
1846 	 * to check for progress in sending the output data -- all that we ask
1847 	 * (at each interval) is that there's been some progress made.  Since
1848 	 * the interrupt routine grabs buffers from the write queue, we can't
1849 	 * trust changes in async_ocnt.  Instead, we use a progress flag.
1850 	 *
1851 	 * Note that loss of carrier will cause the output queue to be flushed,
1852 	 * and we'll wake up again and finish normally.
1853 	 */
1854 	if (!ddi_can_receive_sig() && asy_drain_check != 0) {
1855 		async->async_flags &= ~ASYNC_PROGRESS;
1856 		async->async_timer = timeout(async_progress_check, async,
1857 		    drv_usectohz(asy_drain_check));
1858 	}
1859 	while (async->async_ocnt > 0 ||
1860 	    async->async_ttycommon.t_writeq->q_first != NULL ||
1861 	    (async->async_flags & (ASYNC_BUSY|ASYNC_BREAK|ASYNC_DELAY))) {
1862 		if (cv_wait_sig(&async->async_flags_cv, &asy->asy_excl) == 0)
1863 			break;
1864 	}
1865 	if (async->async_timer != 0) {
1866 		(void) untimeout(async->async_timer);
1867 		async->async_timer = 0;
1868 	}
1869 
1870 nodrain:
1871 	async->async_ocnt = 0;
1872 	if (async->async_xmitblk != NULL)
1873 		freeb(async->async_xmitblk);
1874 	async->async_xmitblk = NULL;
1875 
1876 	/*
1877 	 * If line has HUPCL set or is incompletely opened fix up the modem
1878 	 * lines.
1879 	 */
1880 	DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dclose: next check HUPCL flag\n",
1881 	    instance);
1882 	mutex_enter(&asy->asy_excl_hi);
1883 	if ((async->async_ttycommon.t_cflag & HUPCL) ||
1884 	    (async->async_flags & ASYNC_WOPEN)) {
1885 		DEBUGCONT3(ASY_DEBUG_MODEM,
1886 		    "asy%dclose: HUPCL flag = %x, ASYNC_WOPEN flag = %x\n",
1887 		    instance,
1888 		    async->async_ttycommon.t_cflag & HUPCL,
1889 		    async->async_ttycommon.t_cflag & ASYNC_WOPEN);
1890 		async->async_flags |= ASYNC_DTR_DELAY;
1891 
1892 		/* turn off DTR, RTS but NOT interrupt to 386 */
1893 		if (asy->asy_flags & (ASY_IGNORE_CD|ASY_RTS_DTR_OFF)) {
1894 			DEBUGCONT3(ASY_DEBUG_MODEM,
1895 			    "asy%dclose: ASY_IGNORE_CD flag = %x, "
1896 			    "ASY_RTS_DTR_OFF flag = %x\n",
1897 			    instance,
1898 			    asy->asy_flags & ASY_IGNORE_CD,
1899 			    asy->asy_flags & ASY_RTS_DTR_OFF);
1900 
1901 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1902 			    asy->asy_mcr|OUT2);
1903 		} else {
1904 			DEBUGCONT1(ASY_DEBUG_MODEM,
1905 			    "asy%dclose: Dropping DTR and RTS\n", instance);
1906 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1907 			    OUT2);
1908 		}
1909 		async->async_dtrtid =
1910 		    timeout((void (*)())async_dtr_free,
1911 		    (caddr_t)async, drv_usectohz(asy_min_dtr_low));
1912 	}
1913 	/*
1914 	 * If nobody's using it now, turn off receiver interrupts.
1915 	 */
1916 	if ((async->async_flags & (ASYNC_WOPEN|ASYNC_ISOPEN)) == 0) {
1917 		icr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ICR);
1918 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1919 		    (icr & ~RIEN));
1920 	}
1921 	mutex_exit(&asy->asy_excl_hi);
1922 out:
1923 	ttycommon_close(&async->async_ttycommon);
1924 
1925 	/*
1926 	 * Cancel outstanding "bufcall" request.
1927 	 */
1928 	if (async->async_wbufcid != 0) {
1929 		unbufcall(async->async_wbufcid);
1930 		async->async_wbufcid = 0;
1931 	}
1932 
1933 	/* Note that qprocsoff can't be done until after interrupts are off */
1934 	qprocsoff(q);
1935 	q->q_ptr = WR(q)->q_ptr = NULL;
1936 	async->async_ttycommon.t_readq = NULL;
1937 	async->async_ttycommon.t_writeq = NULL;
1938 
1939 	/*
1940 	 * Clear out device state, except persistant device property flags.
1941 	 */
1942 	async->async_flags &= (ASYNC_DTR_DELAY|ASY_RTS_DTR_OFF);
1943 	cv_broadcast(&async->async_flags_cv);
1944 	mutex_exit(&asy->asy_excl);
1945 
1946 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose: done\n", instance);
1947 	return (0);
1948 }
1949 
1950 static boolean_t
1951 asy_isbusy(struct asycom *asy)
1952 {
1953 	struct asyncline *async;
1954 
1955 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_isbusy\n");
1956 	async = asy->asy_priv;
1957 	ASSERT(mutex_owned(&asy->asy_excl));
1958 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1959 /*
1960  * XXXX this should be recoded
1961  */
1962 	return ((async->async_ocnt > 0) ||
1963 	    ((ddi_get8(asy->asy_iohandle,
1964 	    asy->asy_ioaddr + LSR) & (XSRE|XHRE)) == 0));
1965 }
1966 
1967 static void
1968 asy_waiteot(struct asycom *asy)
1969 {
1970 	/*
1971 	 * Wait for the current transmission block and the
1972 	 * current fifo data to transmit. Once this is done
1973 	 * we may go on.
1974 	 */
1975 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_waiteot\n");
1976 	ASSERT(mutex_owned(&asy->asy_excl));
1977 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1978 	while (asy_isbusy(asy)) {
1979 		mutex_exit(&asy->asy_excl_hi);
1980 		mutex_exit(&asy->asy_excl);
1981 		drv_usecwait(10000);		/* wait .01 */
1982 		mutex_enter(&asy->asy_excl);
1983 		mutex_enter(&asy->asy_excl_hi);
1984 	}
1985 }
1986 
1987 /* asy_reset_fifo -- flush fifos and [re]program fifo control register */
1988 static void
1989 asy_reset_fifo(struct asycom *asy, uchar_t flush)
1990 {
1991 	uchar_t lcr;
1992 
1993 	/* On a 16750, we have to set DLAB in order to set FIFOEXTRA. */
1994 
1995 	if (asy->asy_hwtype >= ASY16750) {
1996 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1997 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1998 		    lcr | DLAB);
1999 	}
2000 
2001 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR,
2002 	    asy->asy_fifor | flush);
2003 
2004 	/* Clear DLAB */
2005 
2006 	if (asy->asy_hwtype >= ASY16750) {
2007 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
2008 	}
2009 }
2010 
2011 /*
2012  * Program the ASY port. Most of the async operation is based on the values
2013  * of 'c_iflag' and 'c_cflag'.
2014  */
2015 
2016 #define	BAUDINDEX(cflg)	(((cflg) & CBAUDEXT) ? \
2017 			(((cflg) & CBAUD) + CBAUD + 1) : ((cflg) & CBAUD))
2018 
2019 static void
2020 asy_program(struct asycom *asy, int mode)
2021 {
2022 	struct asyncline *async;
2023 	int baudrate, c_flag;
2024 	int icr, lcr;
2025 	int flush_reg;
2026 	int ocflags;
2027 #ifdef DEBUG
2028 	int instance;
2029 #endif
2030 
2031 	ASSERT(mutex_owned(&asy->asy_excl));
2032 	ASSERT(mutex_owned(&asy->asy_excl_hi));
2033 
2034 	async = asy->asy_priv;
2035 #ifdef DEBUG
2036 	instance = UNIT(async->async_dev);
2037 	DEBUGCONT2(ASY_DEBUG_PROCS,
2038 	    "asy%d_program: mode = 0x%08X, enter\n", instance, mode);
2039 #endif
2040 
2041 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
2042 
2043 	async->async_ttycommon.t_cflag &= ~(CIBAUD);
2044 
2045 	if (baudrate > CBAUD) {
2046 		async->async_ttycommon.t_cflag |= CIBAUDEXT;
2047 		async->async_ttycommon.t_cflag |=
2048 		    (((baudrate - CBAUD - 1) << IBSHIFT) & CIBAUD);
2049 	} else {
2050 		async->async_ttycommon.t_cflag &= ~CIBAUDEXT;
2051 		async->async_ttycommon.t_cflag |=
2052 		    ((baudrate << IBSHIFT) & CIBAUD);
2053 	}
2054 
2055 	c_flag = async->async_ttycommon.t_cflag &
2056 	    (CLOCAL|CREAD|CSTOPB|CSIZE|PARENB|PARODD|CBAUD|CBAUDEXT);
2057 
2058 	/* disable interrupts */
2059 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
2060 
2061 	ocflags = asy->asy_ocflag;
2062 
2063 	/* flush/reset the status registers */
2064 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
2065 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2066 	asy->asy_msr = flush_reg = ddi_get8(asy->asy_iohandle,
2067 	    asy->asy_ioaddr + MSR);
2068 	/*
2069 	 * The device is programmed in the open sequence, if we
2070 	 * have to hardware handshake, then this is a good time
2071 	 * to check if the device can receive any data.
2072 	 */
2073 
2074 	if ((CRTSCTS & async->async_ttycommon.t_cflag) && !(flush_reg & CTS)) {
2075 		async_flowcontrol_hw_output(asy, FLOW_STOP);
2076 	} else {
2077 		/*
2078 		 * We can not use async_flowcontrol_hw_output(asy, FLOW_START)
2079 		 * here, because if CRTSCTS is clear, we need clear
2080 		 * ASYNC_HW_OUT_FLW bit.
2081 		 */
2082 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
2083 	}
2084 
2085 	/*
2086 	 * If IXON is not set, clear ASYNC_SW_OUT_FLW;
2087 	 * If IXON is set, no matter what IXON flag is before this
2088 	 * function call to asy_program,
2089 	 * we will use the old ASYNC_SW_OUT_FLW status.
2090 	 * Because of handling IXON in the driver, we also should re-calculate
2091 	 * the value of ASYNC_OUT_FLW_RESUME bit, but in fact,
2092 	 * the TCSET* commands which call asy_program
2093 	 * are put into the write queue, so there is no output needed to
2094 	 * be resumed at this point.
2095 	 */
2096 	if (!(IXON & async->async_ttycommon.t_iflag))
2097 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
2098 
2099 	/* manually flush receive buffer or fifo (workaround for buggy fifos) */
2100 	if (mode == ASY_INIT)
2101 		if (asy->asy_use_fifo == FIFO_ON) {
2102 			for (flush_reg = asy->asy_fifo_buf; flush_reg-- > 0; ) {
2103 				(void) ddi_get8(asy->asy_iohandle,
2104 				    asy->asy_ioaddr + DAT);
2105 			}
2106 		} else {
2107 			flush_reg = ddi_get8(asy->asy_iohandle,
2108 			    asy->asy_ioaddr + DAT);
2109 		}
2110 
2111 	if (ocflags != (c_flag & ~CLOCAL) || mode == ASY_INIT) {
2112 		/* Set line control */
2113 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
2114 		lcr &= ~(WLS0|WLS1|STB|PEN|EPS);
2115 
2116 		if (c_flag & CSTOPB)
2117 			lcr |= STB;	/* 2 stop bits */
2118 
2119 		if (c_flag & PARENB)
2120 			lcr |= PEN;
2121 
2122 		if ((c_flag & PARODD) == 0)
2123 			lcr |= EPS;
2124 
2125 		switch (c_flag & CSIZE) {
2126 		case CS5:
2127 			lcr |= BITS5;
2128 			break;
2129 		case CS6:
2130 			lcr |= BITS6;
2131 			break;
2132 		case CS7:
2133 			lcr |= BITS7;
2134 			break;
2135 		case CS8:
2136 			lcr |= BITS8;
2137 			break;
2138 		}
2139 
2140 		/* set the baud rate, unless it is "0" */
2141 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
2142 
2143 		if (baudrate != 0) {
2144 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
2145 			    asyspdtab[baudrate] & 0xff);
2146 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
2147 			    (asyspdtab[baudrate] >> 8) & 0xff);
2148 		}
2149 		/* set the line control modes */
2150 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
2151 
2152 		/*
2153 		 * If we have a FIFO buffer, enable/flush
2154 		 * at intialize time, flush if transitioning from
2155 		 * CREAD off to CREAD on.
2156 		 */
2157 		if ((ocflags & CREAD) == 0 && (c_flag & CREAD) ||
2158 		    mode == ASY_INIT)
2159 			if (asy->asy_use_fifo == FIFO_ON)
2160 				asy_reset_fifo(asy, FIFORXFLSH);
2161 
2162 		/* remember the new cflags */
2163 		asy->asy_ocflag = c_flag & ~CLOCAL;
2164 	}
2165 
2166 	if (baudrate == 0)
2167 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
2168 		    (asy->asy_mcr & RTS) | OUT2);
2169 	else
2170 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
2171 		    asy->asy_mcr | OUT2);
2172 
2173 	/*
2174 	 * Call the modem status interrupt handler to check for the carrier
2175 	 * in case CLOCAL was turned off after the carrier came on.
2176 	 * (Note: Modem status interrupt is not enabled if CLOCAL is ON.)
2177 	 */
2178 	async_msint(asy);
2179 
2180 	/* Set interrupt control */
2181 	DEBUGCONT3(ASY_DEBUG_MODM2,
2182 	    "asy%d_program: c_flag & CLOCAL = %x t_cflag & CRTSCTS = %x\n",
2183 	    instance, c_flag & CLOCAL,
2184 	    async->async_ttycommon.t_cflag & CRTSCTS);
2185 
2186 	if ((c_flag & CLOCAL) && !(async->async_ttycommon.t_cflag & CRTSCTS))
2187 		/*
2188 		 * direct-wired line ignores DCD, so we don't enable modem
2189 		 * status interrupts.
2190 		 */
2191 		icr = (TIEN | SIEN);
2192 	else
2193 		icr = (TIEN | SIEN | MIEN);
2194 
2195 	if (c_flag & CREAD)
2196 		icr |= RIEN;
2197 
2198 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, icr);
2199 	DEBUGCONT1(ASY_DEBUG_PROCS, "asy%d_program: done\n", instance);
2200 }
2201 
2202 static boolean_t
2203 asy_baudok(struct asycom *asy)
2204 {
2205 	struct asyncline *async = asy->asy_priv;
2206 	int baudrate;
2207 
2208 
2209 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
2210 
2211 	if (baudrate >= sizeof (asyspdtab)/sizeof (*asyspdtab))
2212 		return (0);
2213 
2214 	return (baudrate == 0 || asyspdtab[baudrate]);
2215 }
2216 
2217 /*
2218  * asyintr() is the High Level Interrupt Handler.
2219  *
2220  * There are four different interrupt types indexed by ISR register values:
2221  *		0: modem
2222  *		1: Tx holding register is empty, ready for next char
2223  *		2: Rx register now holds a char to be picked up
2224  *		3: error or break on line
2225  * This routine checks the Bit 0 (interrupt-not-pending) to determine if
2226  * the interrupt is from this port.
2227  */
2228 uint_t
2229 asyintr(caddr_t argasy)
2230 {
2231 	struct asycom		*asy = (struct asycom *)argasy;
2232 	struct asyncline	*async;
2233 	int			ret_status = DDI_INTR_UNCLAIMED;
2234 	uchar_t			interrupt_id, lsr;
2235 
2236 	interrupt_id = ddi_get8(asy->asy_iohandle,
2237 	    asy->asy_ioaddr + ISR) & 0x0F;
2238 	async = asy->asy_priv;
2239 
2240 	if ((async == NULL) ||
2241 	    !(async->async_flags & (ASYNC_ISOPEN|ASYNC_WOPEN))) {
2242 		if (interrupt_id & NOINTERRUPT)
2243 			return (DDI_INTR_UNCLAIMED);
2244 		else {
2245 			/*
2246 			 * reset the device by:
2247 			 *	reading line status
2248 			 *	reading any data from data status register
2249 			 *	reading modem status
2250 			 */
2251 			(void) ddi_get8(asy->asy_iohandle,
2252 			    asy->asy_ioaddr + LSR);
2253 			(void) ddi_get8(asy->asy_iohandle,
2254 			    asy->asy_ioaddr + DAT);
2255 			asy->asy_msr = ddi_get8(asy->asy_iohandle,
2256 			    asy->asy_ioaddr + MSR);
2257 			return (DDI_INTR_CLAIMED);
2258 		}
2259 	}
2260 
2261 	mutex_enter(&asy->asy_excl_hi);
2262 
2263 	if (asy->asy_flags & ASY_DDI_SUSPENDED) {
2264 		mutex_exit(&asy->asy_excl_hi);
2265 		return (DDI_INTR_CLAIMED);
2266 	}
2267 
2268 	/*
2269 	 * We will loop until the interrupt line is pulled low. asy
2270 	 * interrupt is edge triggered.
2271 	 */
2272 	/* CSTYLED */
2273 	for (;; interrupt_id =
2274 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR) & 0x0F)) {
2275 
2276 		if (interrupt_id & NOINTERRUPT)
2277 			break;
2278 		ret_status = DDI_INTR_CLAIMED;
2279 
2280 		DEBUGCONT1(ASY_DEBUG_INTR, "asyintr: interrupt_id = 0x%d\n",
2281 		    interrupt_id);
2282 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2283 		switch (interrupt_id) {
2284 		case RxRDY:
2285 		case RSTATUS:
2286 		case FFTMOUT:
2287 			/* receiver interrupt or receiver errors */
2288 			async_rxint(asy, lsr);
2289 			break;
2290 		case TxRDY:
2291 			/* transmit interrupt */
2292 			async_txint(asy);
2293 			continue;
2294 		case MSTATUS:
2295 			/* modem status interrupt */
2296 			async_msint(asy);
2297 			break;
2298 		}
2299 		if ((lsr & XHRE) && (async->async_flags & ASYNC_BUSY) &&
2300 		    (async->async_ocnt > 0))
2301 			async_txint(asy);
2302 	}
2303 	mutex_exit(&asy->asy_excl_hi);
2304 	return (ret_status);
2305 }
2306 
2307 /*
2308  * Transmitter interrupt service routine.
2309  * If there is more data to transmit in the current pseudo-DMA block,
2310  * send the next character if output is not stopped or draining.
2311  * Otherwise, queue up a soft interrupt.
2312  *
2313  * XXX -  Needs review for HW FIFOs.
2314  */
2315 static void
2316 async_txint(struct asycom *asy)
2317 {
2318 	struct asyncline *async = asy->asy_priv;
2319 	int		fifo_len;
2320 
2321 	/*
2322 	 * If ASYNC_BREAK or ASYNC_OUT_SUSPEND has been set, return to
2323 	 * asyintr()'s context to claim the interrupt without performing
2324 	 * any action. No character will be loaded into FIFO/THR until
2325 	 * timed or untimed break is removed
2326 	 */
2327 	if (async->async_flags & (ASYNC_BREAK|ASYNC_OUT_SUSPEND))
2328 		return;
2329 
2330 	fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
2331 	if (fifo_len > asy_max_tx_fifo)
2332 		fifo_len = asy_max_tx_fifo;
2333 
2334 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
2335 		fifo_len--;
2336 
2337 	if (async->async_ocnt > 0 && fifo_len > 0 &&
2338 	    !(async->async_flags &
2339 	    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_STOPPED))) {
2340 		while (fifo_len-- > 0 && async->async_ocnt-- > 0) {
2341 			ddi_put8(asy->asy_iohandle,
2342 			    asy->asy_ioaddr + DAT, *async->async_optr++);
2343 		}
2344 		async->async_flags |= ASYNC_PROGRESS;
2345 	}
2346 
2347 	if (fifo_len <= 0)
2348 		return;
2349 
2350 	ASYSETSOFT(asy);
2351 }
2352 
2353 /*
2354  * Interrupt on port: handle PPS event.  This function is only called
2355  * for a port on which PPS event handling has been enabled.
2356  */
2357 static void
2358 asy_ppsevent(struct asycom *asy, int msr)
2359 {
2360 	if (asy->asy_flags & ASY_PPS_EDGE) {
2361 		/* Have seen leading edge, now look for and record drop */
2362 		if ((msr & DCD) == 0)
2363 			asy->asy_flags &= ~ASY_PPS_EDGE;
2364 		/*
2365 		 * Waiting for leading edge, look for rise; stamp event and
2366 		 * calibrate kernel clock.
2367 		 */
2368 	} else if (msr & DCD) {
2369 			/*
2370 			 * This code captures a timestamp at the designated
2371 			 * transition of the PPS signal (DCD asserted).  The
2372 			 * code provides a pointer to the timestamp, as well
2373 			 * as the hardware counter value at the capture.
2374 			 *
2375 			 * Note: the kernel has nano based time values while
2376 			 * NTP requires micro based, an in-line fast algorithm
2377 			 * to convert nsec to usec is used here -- see hrt2ts()
2378 			 * in common/os/timers.c for a full description.
2379 			 */
2380 			struct timeval *tvp = &asy_ppsev.tv;
2381 			timestruc_t ts;
2382 			long nsec, usec;
2383 
2384 			asy->asy_flags |= ASY_PPS_EDGE;
2385 			LED_OFF;
2386 			gethrestime(&ts);
2387 			LED_ON;
2388 			nsec = ts.tv_nsec;
2389 			usec = nsec + (nsec >> 2);
2390 			usec = nsec + (usec >> 1);
2391 			usec = nsec + (usec >> 2);
2392 			usec = nsec + (usec >> 4);
2393 			usec = nsec - (usec >> 3);
2394 			usec = nsec + (usec >> 2);
2395 			usec = nsec + (usec >> 3);
2396 			usec = nsec + (usec >> 4);
2397 			usec = nsec + (usec >> 1);
2398 			usec = nsec + (usec >> 6);
2399 			tvp->tv_usec = usec >> 10;
2400 			tvp->tv_sec = ts.tv_sec;
2401 
2402 			++asy_ppsev.serial;
2403 
2404 			/*
2405 			 * Because the kernel keeps a high-resolution time,
2406 			 * pass the current highres timestamp in tvp and zero
2407 			 * in usec.
2408 			 */
2409 			ddi_hardpps(tvp, 0);
2410 	}
2411 }
2412 
2413 /*
2414  * Receiver interrupt: RxRDY interrupt, FIFO timeout interrupt or receive
2415  * error interrupt.
2416  * Try to put the character into the circular buffer for this line; if it
2417  * overflows, indicate a circular buffer overrun. If this port is always
2418  * to be serviced immediately, or the character is a STOP character, or
2419  * more than 15 characters have arrived, queue up a soft interrupt to
2420  * drain the circular buffer.
2421  * XXX - needs review for hw FIFOs support.
2422  */
2423 
2424 static void
2425 async_rxint(struct asycom *asy, uchar_t lsr)
2426 {
2427 	struct asyncline *async = asy->asy_priv;
2428 	uchar_t c;
2429 	uint_t s, needsoft = 0;
2430 	tty_common_t *tp;
2431 	int looplim = asy->asy_fifo_buf * 2;
2432 
2433 	tp = &async->async_ttycommon;
2434 	if (!(tp->t_cflag & CREAD)) {
2435 		while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2436 			(void) (ddi_get8(asy->asy_iohandle,
2437 			    asy->asy_ioaddr + DAT) & 0xff);
2438 			lsr = ddi_get8(asy->asy_iohandle,
2439 			    asy->asy_ioaddr + LSR);
2440 			if (looplim-- < 0)		/* limit loop */
2441 				break;
2442 		}
2443 		return; /* line is not open for read? */
2444 	}
2445 
2446 	while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2447 		c = 0;
2448 		s = 0;				/* reset error status */
2449 		if (lsr & RCA) {
2450 			c = ddi_get8(asy->asy_iohandle,
2451 			    asy->asy_ioaddr + DAT) & 0xff;
2452 
2453 			/*
2454 			 * We handle XON/XOFF char if IXON is set,
2455 			 * but if received char is _POSIX_VDISABLE,
2456 			 * we left it to the up level module.
2457 			 */
2458 			if (tp->t_iflag & IXON) {
2459 				if ((c == async->async_stopc) &&
2460 				    (c != _POSIX_VDISABLE)) {
2461 					async_flowcontrol_sw_output(asy,
2462 					    FLOW_STOP);
2463 					goto check_looplim;
2464 				} else if ((c == async->async_startc) &&
2465 				    (c != _POSIX_VDISABLE)) {
2466 					async_flowcontrol_sw_output(asy,
2467 					    FLOW_START);
2468 					needsoft = 1;
2469 					goto check_looplim;
2470 				}
2471 				if ((tp->t_iflag & IXANY) &&
2472 				    (async->async_flags & ASYNC_SW_OUT_FLW)) {
2473 					async_flowcontrol_sw_output(asy,
2474 					    FLOW_START);
2475 					needsoft = 1;
2476 				}
2477 			}
2478 		}
2479 
2480 		/*
2481 		 * Check for character break sequence
2482 		 */
2483 		if ((abort_enable == KIOCABORTALTERNATE) &&
2484 		    (asy->asy_flags & ASY_CONSOLE)) {
2485 			if (abort_charseq_recognize(c))
2486 				abort_sequence_enter((char *)NULL);
2487 		}
2488 
2489 		/* Handle framing errors */
2490 		if (lsr & (PARERR|FRMERR|BRKDET|OVRRUN)) {
2491 			if (lsr & PARERR) {
2492 				if (tp->t_iflag & INPCK) /* parity enabled */
2493 					s |= PERROR;
2494 			}
2495 
2496 			if (lsr & (FRMERR|BRKDET))
2497 				s |= FRERROR;
2498 			if (lsr & OVRRUN) {
2499 				async->async_hw_overrun = 1;
2500 				s |= OVERRUN;
2501 			}
2502 		}
2503 
2504 		if (s == 0)
2505 			if ((tp->t_iflag & PARMRK) &&
2506 			    !(tp->t_iflag & (IGNPAR|ISTRIP)) &&
2507 			    (c == 0377))
2508 				if (RING_POK(async, 2)) {
2509 					RING_PUT(async, 0377);
2510 					RING_PUT(async, c);
2511 				} else
2512 					async->async_sw_overrun = 1;
2513 			else
2514 				if (RING_POK(async, 1))
2515 					RING_PUT(async, c);
2516 				else
2517 					async->async_sw_overrun = 1;
2518 		else
2519 			if (s & FRERROR) /* Handle framing errors */
2520 				if (c == 0)
2521 					if ((asy->asy_flags & ASY_CONSOLE) &&
2522 					    (abort_enable !=
2523 					    KIOCABORTALTERNATE))
2524 						abort_sequence_enter((char *)0);
2525 					else
2526 						async->async_break++;
2527 				else
2528 					if (RING_POK(async, 1))
2529 						RING_MARK(async, c, s);
2530 					else
2531 						async->async_sw_overrun = 1;
2532 			else /* Parity errors are handled by ldterm */
2533 				if (RING_POK(async, 1))
2534 					RING_MARK(async, c, s);
2535 				else
2536 					async->async_sw_overrun = 1;
2537 check_looplim:
2538 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2539 		if (looplim-- < 0)		/* limit loop */
2540 			break;
2541 	}
2542 	if ((RING_CNT(async) > (RINGSIZE * 3)/4) &&
2543 	    !(async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2544 		async_flowcontrol_hw_input(asy, FLOW_STOP, IN_FLOW_RINGBUFF);
2545 		(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2546 		    IN_FLOW_RINGBUFF);
2547 	}
2548 
2549 	if ((async->async_flags & ASYNC_SERVICEIMM) || needsoft ||
2550 	    (RING_FRAC(async)) || (async->async_polltid == 0))
2551 		ASYSETSOFT(asy);	/* need a soft interrupt */
2552 }
2553 
2554 /*
2555  * Modem status interrupt.
2556  *
2557  * (Note: It is assumed that the MSR hasn't been read by asyintr().)
2558  */
2559 
2560 static void
2561 async_msint(struct asycom *asy)
2562 {
2563 	struct asyncline *async = asy->asy_priv;
2564 	int msr, t_cflag = async->async_ttycommon.t_cflag;
2565 #ifdef DEBUG
2566 	int instance = UNIT(async->async_dev);
2567 #endif
2568 
2569 async_msint_retry:
2570 	/* this resets the interrupt */
2571 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2572 	DEBUGCONT10(ASY_DEBUG_STATE,
2573 	    "async%d_msint call #%d:\n"
2574 	    "   transition: %3s %3s %3s %3s\n"
2575 	    "current state: %3s %3s %3s %3s\n",
2576 	    instance,
2577 	    ++(asy->asy_msint_cnt),
2578 	    (msr & DCTS) ? "DCTS" : "    ",
2579 	    (msr & DDSR) ? "DDSR" : "    ",
2580 	    (msr & DRI)  ? "DRI " : "    ",
2581 	    (msr & DDCD) ? "DDCD" : "    ",
2582 	    (msr & CTS)  ? "CTS " : "    ",
2583 	    (msr & DSR)  ? "DSR " : "    ",
2584 	    (msr & RI)   ? "RI  " : "    ",
2585 	    (msr & DCD)  ? "DCD " : "    ");
2586 
2587 	/* If CTS status is changed, do H/W output flow control */
2588 	if ((t_cflag & CRTSCTS) && (((asy->asy_msr ^ msr) & CTS) != 0))
2589 		async_flowcontrol_hw_output(asy,
2590 		    msr & CTS ? FLOW_START : FLOW_STOP);
2591 	/*
2592 	 * Reading MSR resets the interrupt, we save the
2593 	 * value of msr so that other functions could examine MSR by
2594 	 * looking at asy_msr.
2595 	 */
2596 	asy->asy_msr = (uchar_t)msr;
2597 
2598 	/* Handle PPS event */
2599 	if (asy->asy_flags & ASY_PPS)
2600 		asy_ppsevent(asy, msr);
2601 
2602 	async->async_ext++;
2603 	ASYSETSOFT(asy);
2604 	/*
2605 	 * We will make sure that the modem status presented to us
2606 	 * during the previous read has not changed. If the chip samples
2607 	 * the modem status on the falling edge of the interrupt line,
2608 	 * and uses this state as the base for detecting change of modem
2609 	 * status, we would miss a change of modem status event that occured
2610 	 * after we initiated a read MSR operation.
2611 	 */
2612 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2613 	if (STATES(msr) != STATES(asy->asy_msr))
2614 		goto	async_msint_retry;
2615 }
2616 
2617 /*
2618  * Handle a second-stage interrupt.
2619  */
2620 /*ARGSUSED*/
2621 uint_t
2622 asysoftintr(caddr_t intarg)
2623 {
2624 	struct asycom *asy = (struct asycom *)intarg;
2625 	struct asyncline *async;
2626 	int rv;
2627 	uint_t cc;
2628 
2629 	/*
2630 	 * Test and clear soft interrupt.
2631 	 */
2632 	mutex_enter(&asy->asy_soft_lock);
2633 	DEBUGCONT0(ASY_DEBUG_PROCS, "asysoftintr: enter\n");
2634 	rv = asy->asysoftpend;
2635 	if (rv != 0)
2636 		asy->asysoftpend = 0;
2637 	mutex_exit(&asy->asy_soft_lock);
2638 
2639 	if (rv) {
2640 		if (asy->asy_priv == NULL)
2641 			return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2642 		async = (struct asyncline *)asy->asy_priv;
2643 		mutex_enter(&asy->asy_excl_hi);
2644 		if (asy->asy_flags & ASY_NEEDSOFT) {
2645 			asy->asy_flags &= ~ASY_NEEDSOFT;
2646 			mutex_exit(&asy->asy_excl_hi);
2647 			async_softint(asy);
2648 			mutex_enter(&asy->asy_excl_hi);
2649 		}
2650 
2651 		/*
2652 		 * There are some instances where the softintr is not
2653 		 * scheduled and hence not called. It so happens that
2654 		 * causes the last few characters to be stuck in the
2655 		 * ringbuffer. Hence, call the handler once again so
2656 		 * the last few characters are cleared.
2657 		 */
2658 		cc = RING_CNT(async);
2659 		mutex_exit(&asy->asy_excl_hi);
2660 		if (cc > 0)
2661 			(void) async_softint(asy);
2662 	}
2663 	return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2664 }
2665 
2666 /*
2667  * Handle a software interrupt.
2668  */
2669 static void
2670 async_softint(struct asycom *asy)
2671 {
2672 	struct asyncline *async = asy->asy_priv;
2673 	uint_t	cc;
2674 	mblk_t	*bp;
2675 	queue_t	*q;
2676 	uchar_t	val;
2677 	uchar_t	c;
2678 	tty_common_t	*tp;
2679 	int nb;
2680 	int instance = UNIT(async->async_dev);
2681 
2682 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint\n", instance);
2683 	mutex_enter(&asy->asy_excl_hi);
2684 	if (asy->asy_flags & ASY_DOINGSOFT) {
2685 		asy->asy_flags |= ASY_DOINGSOFT_RETRY;
2686 		mutex_exit(&asy->asy_excl_hi);
2687 		return;
2688 	}
2689 	asy->asy_flags |= ASY_DOINGSOFT;
2690 begin:
2691 	asy->asy_flags &= ~ASY_DOINGSOFT_RETRY;
2692 	mutex_exit(&asy->asy_excl_hi);
2693 	mutex_enter(&asy->asy_excl);
2694 	tp = &async->async_ttycommon;
2695 	q = tp->t_readq;
2696 	if (async->async_flags & ASYNC_OUT_FLW_RESUME) {
2697 		if (async->async_ocnt > 0) {
2698 			mutex_enter(&asy->asy_excl_hi);
2699 			async_resume(async);
2700 			mutex_exit(&asy->asy_excl_hi);
2701 		} else {
2702 			if (async->async_xmitblk)
2703 				freeb(async->async_xmitblk);
2704 			async->async_xmitblk = NULL;
2705 			async_start(async);
2706 		}
2707 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
2708 	}
2709 	mutex_enter(&asy->asy_excl_hi);
2710 	if (async->async_ext) {
2711 		async->async_ext = 0;
2712 		/* check for carrier up */
2713 		DEBUGCONT3(ASY_DEBUG_MODM2,
2714 		    "async%d_softint: asy_msr & DCD = %x, "
2715 		    "tp->t_flags & TS_SOFTCAR = %x\n",
2716 		    instance, asy->asy_msr & DCD, tp->t_flags & TS_SOFTCAR);
2717 
2718 		if (asy->asy_msr & DCD) {
2719 			/* carrier present */
2720 			if ((async->async_flags & ASYNC_CARR_ON) == 0) {
2721 				DEBUGCONT1(ASY_DEBUG_MODM2,
2722 				    "async%d_softint: set ASYNC_CARR_ON\n",
2723 				    instance);
2724 				async->async_flags |= ASYNC_CARR_ON;
2725 				if (async->async_flags & ASYNC_ISOPEN) {
2726 					mutex_exit(&asy->asy_excl_hi);
2727 					mutex_exit(&asy->asy_excl);
2728 					(void) putctl(q, M_UNHANGUP);
2729 					mutex_enter(&asy->asy_excl);
2730 					mutex_enter(&asy->asy_excl_hi);
2731 				}
2732 				cv_broadcast(&async->async_flags_cv);
2733 			}
2734 		} else {
2735 			if ((async->async_flags & ASYNC_CARR_ON) &&
2736 			    !(tp->t_cflag & CLOCAL) &&
2737 			    !(tp->t_flags & TS_SOFTCAR)) {
2738 				int flushflag;
2739 
2740 				DEBUGCONT1(ASY_DEBUG_MODEM,
2741 				    "async%d_softint: carrier dropped, "
2742 				    "so drop DTR\n",
2743 				    instance);
2744 				/*
2745 				 * Carrier went away.
2746 				 * Drop DTR, abort any output in
2747 				 * progress, indicate that output is
2748 				 * not stopped, and send a hangup
2749 				 * notification upstream.
2750 				 */
2751 				val = ddi_get8(asy->asy_iohandle,
2752 				    asy->asy_ioaddr + MCR);
2753 				ddi_put8(asy->asy_iohandle,
2754 				    asy->asy_ioaddr + MCR, (val & ~DTR));
2755 
2756 				if (async->async_flags & ASYNC_BUSY) {
2757 					DEBUGCONT0(ASY_DEBUG_BUSY,
2758 					    "async_softint: "
2759 					    "Carrier dropped.  "
2760 					    "Clearing async_ocnt\n");
2761 					async->async_ocnt = 0;
2762 				}	/* if */
2763 
2764 				async->async_flags &= ~ASYNC_STOPPED;
2765 				if (async->async_flags & ASYNC_ISOPEN) {
2766 					mutex_exit(&asy->asy_excl_hi);
2767 					mutex_exit(&asy->asy_excl);
2768 					(void) putctl(q, M_HANGUP);
2769 					mutex_enter(&asy->asy_excl);
2770 					DEBUGCONT1(ASY_DEBUG_MODEM,
2771 					    "async%d_softint: "
2772 					    "putctl(q, M_HANGUP)\n",
2773 					    instance);
2774 					/*
2775 					 * Flush FIFO buffers
2776 					 * Any data left in there is invalid now
2777 					 */
2778 					if (asy->asy_use_fifo == FIFO_ON)
2779 						asy_reset_fifo(asy, FIFOTXFLSH);
2780 					/*
2781 					 * Flush our write queue if we have one.
2782 					 * If we're in the midst of close, then
2783 					 * flush everything. Don't leave stale
2784 					 * ioctls lying about.
2785 					 */
2786 					flushflag = (async->async_flags &
2787 					    ASYNC_CLOSING) ? FLUSHALL :
2788 					    FLUSHDATA;
2789 					flushq(tp->t_writeq, flushflag);
2790 
2791 					/* active msg */
2792 					bp = async->async_xmitblk;
2793 					if (bp != NULL) {
2794 						freeb(bp);
2795 						async->async_xmitblk = NULL;
2796 					}
2797 
2798 					mutex_enter(&asy->asy_excl_hi);
2799 					async->async_flags &= ~ASYNC_BUSY;
2800 					/*
2801 					 * This message warns of Carrier loss
2802 					 * with data left to transmit can hang
2803 					 * the system.
2804 					 */
2805 					DEBUGCONT0(ASY_DEBUG_MODEM,
2806 					    "async_softint: Flushing to "
2807 					    "prevent HUPCL hanging\n");
2808 				}	/* if (ASYNC_ISOPEN) */
2809 			}	/* if (ASYNC_CARR_ON && CLOCAL) */
2810 			async->async_flags &= ~ASYNC_CARR_ON;
2811 			cv_broadcast(&async->async_flags_cv);
2812 		}	/* else */
2813 	}	/* if (async->async_ext) */
2814 
2815 	mutex_exit(&asy->asy_excl_hi);
2816 
2817 	/*
2818 	 * If data has been added to the circular buffer, remove
2819 	 * it from the buffer, and send it up the stream if there's
2820 	 * somebody listening. Try to do it 16 bytes at a time. If we
2821 	 * have more than 16 bytes to move, move 16 byte chunks and
2822 	 * leave the rest for next time around (maybe it will grow).
2823 	 */
2824 	mutex_enter(&asy->asy_excl_hi);
2825 	if (!(async->async_flags & ASYNC_ISOPEN)) {
2826 		RING_INIT(async);
2827 		goto rv;
2828 	}
2829 	if ((cc = RING_CNT(async)) == 0)
2830 		goto rv;
2831 	mutex_exit(&asy->asy_excl_hi);
2832 
2833 	if (!canput(q)) {
2834 		mutex_enter(&asy->asy_excl_hi);
2835 		if (!(async->async_inflow_source & IN_FLOW_STREAMS)) {
2836 			async_flowcontrol_hw_input(asy, FLOW_STOP,
2837 			    IN_FLOW_STREAMS);
2838 			(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2839 			    IN_FLOW_STREAMS);
2840 		}
2841 		goto rv;
2842 	}
2843 	if (async->async_inflow_source & IN_FLOW_STREAMS) {
2844 		mutex_enter(&asy->asy_excl_hi);
2845 		async_flowcontrol_hw_input(asy, FLOW_START,
2846 		    IN_FLOW_STREAMS);
2847 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2848 		    IN_FLOW_STREAMS);
2849 		mutex_exit(&asy->asy_excl_hi);
2850 	}
2851 
2852 	DEBUGCONT2(ASY_DEBUG_INPUT, "async%d_softint: %d char(s) in queue.\n",
2853 	    instance, cc);
2854 
2855 	if (!(bp = allocb(cc, BPRI_MED))) {
2856 		mutex_exit(&asy->asy_excl);
2857 		ttycommon_qfull(&async->async_ttycommon, q);
2858 		mutex_enter(&asy->asy_excl);
2859 		mutex_enter(&asy->asy_excl_hi);
2860 		goto rv;
2861 	}
2862 	mutex_enter(&asy->asy_excl_hi);
2863 	do {
2864 		if (RING_ERR(async, S_ERRORS)) {
2865 			RING_UNMARK(async);
2866 			c = RING_GET(async);
2867 			break;
2868 		} else
2869 			*bp->b_wptr++ = RING_GET(async);
2870 	} while (--cc);
2871 	mutex_exit(&asy->asy_excl_hi);
2872 	mutex_exit(&asy->asy_excl);
2873 	if (bp->b_wptr > bp->b_rptr) {
2874 			if (!canput(q)) {
2875 				asyerror(CE_NOTE, "asy%d: local queue full",
2876 				    instance);
2877 				freemsg(bp);
2878 			} else
2879 				(void) putq(q, bp);
2880 	} else
2881 		freemsg(bp);
2882 	/*
2883 	 * If we have a parity error, then send
2884 	 * up an M_BREAK with the "bad"
2885 	 * character as an argument. Let ldterm
2886 	 * figure out what to do with the error.
2887 	 */
2888 	if (cc) {
2889 		(void) putctl1(q, M_BREAK, c);
2890 		ASYSETSOFT(async->async_common);	/* finish cc chars */
2891 	}
2892 	mutex_enter(&asy->asy_excl);
2893 	mutex_enter(&asy->asy_excl_hi);
2894 rv:
2895 	if ((RING_CNT(async) < (RINGSIZE/4)) &&
2896 	    (async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2897 		async_flowcontrol_hw_input(asy, FLOW_START, IN_FLOW_RINGBUFF);
2898 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2899 		    IN_FLOW_RINGBUFF);
2900 	}
2901 
2902 	/*
2903 	 * If a transmission has finished, indicate that it's finished,
2904 	 * and start that line up again.
2905 	 */
2906 	if (async->async_break > 0) {
2907 		nb = async->async_break;
2908 		async->async_break = 0;
2909 		if (async->async_flags & ASYNC_ISOPEN) {
2910 			mutex_exit(&asy->asy_excl_hi);
2911 			mutex_exit(&asy->asy_excl);
2912 			for (; nb > 0; nb--)
2913 				(void) putctl(q, M_BREAK);
2914 			mutex_enter(&asy->asy_excl);
2915 			mutex_enter(&asy->asy_excl_hi);
2916 		}
2917 	}
2918 	if (async->async_ocnt <= 0 && (async->async_flags & ASYNC_BUSY)) {
2919 		DEBUGCONT2(ASY_DEBUG_BUSY,
2920 		    "async%d_softint: Clearing ASYNC_BUSY.  async_ocnt=%d\n",
2921 		    instance,
2922 		    async->async_ocnt);
2923 		async->async_flags &= ~ASYNC_BUSY;
2924 		mutex_exit(&asy->asy_excl_hi);
2925 		if (async->async_xmitblk)
2926 			freeb(async->async_xmitblk);
2927 		async->async_xmitblk = NULL;
2928 		async_start(async);
2929 		/*
2930 		 * If the flag isn't set after doing the async_start above, we
2931 		 * may have finished all the queued output.  Signal any thread
2932 		 * stuck in close.
2933 		 */
2934 		if (!(async->async_flags & ASYNC_BUSY))
2935 			cv_broadcast(&async->async_flags_cv);
2936 		mutex_enter(&asy->asy_excl_hi);
2937 	}
2938 	/*
2939 	 * A note about these overrun bits: all they do is *tell* someone
2940 	 * about an error- They do not track multiple errors. In fact,
2941 	 * you could consider them latched register bits if you like.
2942 	 * We are only interested in printing the error message once for
2943 	 * any cluster of overrun errrors.
2944 	 */
2945 	if (async->async_hw_overrun) {
2946 		if (async->async_flags & ASYNC_ISOPEN) {
2947 			mutex_exit(&asy->asy_excl_hi);
2948 			mutex_exit(&asy->asy_excl);
2949 			asyerror(CE_NOTE, "asy%d: silo overflow", instance);
2950 			mutex_enter(&asy->asy_excl);
2951 			mutex_enter(&asy->asy_excl_hi);
2952 		}
2953 		async->async_hw_overrun = 0;
2954 	}
2955 	if (async->async_sw_overrun) {
2956 		if (async->async_flags & ASYNC_ISOPEN) {
2957 			mutex_exit(&asy->asy_excl_hi);
2958 			mutex_exit(&asy->asy_excl);
2959 			asyerror(CE_NOTE, "asy%d: ring buffer overflow",
2960 			    instance);
2961 			mutex_enter(&asy->asy_excl);
2962 			mutex_enter(&asy->asy_excl_hi);
2963 		}
2964 		async->async_sw_overrun = 0;
2965 	}
2966 	if (asy->asy_flags & ASY_DOINGSOFT_RETRY) {
2967 		mutex_exit(&asy->asy_excl);
2968 		goto begin;
2969 	}
2970 	asy->asy_flags &= ~ASY_DOINGSOFT;
2971 	mutex_exit(&asy->asy_excl_hi);
2972 	mutex_exit(&asy->asy_excl);
2973 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint: done\n", instance);
2974 }
2975 
2976 /*
2977  * Restart output on a line after a delay or break timer expired.
2978  */
2979 static void
2980 async_restart(void *arg)
2981 {
2982 	struct asyncline *async = (struct asyncline *)arg;
2983 	struct asycom *asy = async->async_common;
2984 	uchar_t lcr;
2985 
2986 	/*
2987 	 * If break timer expired, turn off the break bit.
2988 	 */
2989 #ifdef DEBUG
2990 	int instance = UNIT(async->async_dev);
2991 
2992 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_restart\n", instance);
2993 #endif
2994 	mutex_enter(&asy->asy_excl);
2995 	/*
2996 	 * If ASYNC_OUT_SUSPEND is also set, we don't really
2997 	 * clean the HW break, TIOCCBRK is responsible for this.
2998 	 */
2999 	if ((async->async_flags & ASYNC_BREAK) &&
3000 	    !(async->async_flags & ASYNC_OUT_SUSPEND)) {
3001 		mutex_enter(&asy->asy_excl_hi);
3002 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
3003 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3004 		    (lcr & ~SETBREAK));
3005 		mutex_exit(&asy->asy_excl_hi);
3006 	}
3007 	async->async_flags &= ~(ASYNC_DELAY|ASYNC_BREAK);
3008 	cv_broadcast(&async->async_flags_cv);
3009 	async_start(async);
3010 
3011 	mutex_exit(&asy->asy_excl);
3012 }
3013 
3014 static void
3015 async_start(struct asyncline *async)
3016 {
3017 	async_nstart(async, 0);
3018 }
3019 
3020 /*
3021  * Start output on a line, unless it's busy, frozen, or otherwise.
3022  */
3023 /*ARGSUSED*/
3024 static void
3025 async_nstart(struct asyncline *async, int mode)
3026 {
3027 	struct asycom *asy = async->async_common;
3028 	int cc;
3029 	queue_t *q;
3030 	mblk_t *bp;
3031 	uchar_t *xmit_addr;
3032 	uchar_t	val;
3033 	int	fifo_len = 1;
3034 	boolean_t didsome;
3035 	mblk_t *nbp;
3036 
3037 #ifdef DEBUG
3038 	int instance = UNIT(async->async_dev);
3039 
3040 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_nstart\n", instance);
3041 #endif
3042 	if (asy->asy_use_fifo == FIFO_ON) {
3043 		fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
3044 		if (fifo_len > asy_max_tx_fifo)
3045 			fifo_len = asy_max_tx_fifo;
3046 	}
3047 
3048 	ASSERT(mutex_owned(&asy->asy_excl));
3049 
3050 	/*
3051 	 * If the chip is busy (i.e., we're waiting for a break timeout
3052 	 * to expire, or for the current transmission to finish, or for
3053 	 * output to finish draining from chip), don't grab anything new.
3054 	 */
3055 	if (async->async_flags & (ASYNC_BREAK|ASYNC_BUSY)) {
3056 		DEBUGCONT2((mode? ASY_DEBUG_OUT : 0),
3057 		    "async%d_nstart: start %s.\n",
3058 		    instance,
3059 		    async->async_flags & ASYNC_BREAK ? "break" : "busy");
3060 		return;
3061 	}
3062 
3063 	/*
3064 	 * Check only pended sw input flow control.
3065 	 */
3066 	mutex_enter(&asy->asy_excl_hi);
3067 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
3068 		fifo_len--;
3069 	mutex_exit(&asy->asy_excl_hi);
3070 
3071 	/*
3072 	 * If we're waiting for a delay timeout to expire, don't grab
3073 	 * anything new.
3074 	 */
3075 	if (async->async_flags & ASYNC_DELAY) {
3076 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
3077 		    "async%d_nstart: start ASYNC_DELAY.\n", instance);
3078 		return;
3079 	}
3080 
3081 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
3082 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
3083 		    "async%d_nstart: start writeq is null.\n", instance);
3084 		return;	/* not attached to a stream */
3085 	}
3086 
3087 	for (;;) {
3088 		if ((bp = getq(q)) == NULL)
3089 			return;	/* no data to transmit */
3090 
3091 		/*
3092 		 * We have a message block to work on.
3093 		 * Check whether it's a break, a delay, or an ioctl (the latter
3094 		 * occurs if the ioctl in question was waiting for the output
3095 		 * to drain).  If it's one of those, process it immediately.
3096 		 */
3097 		switch (bp->b_datap->db_type) {
3098 
3099 		case M_BREAK:
3100 			/*
3101 			 * Set the break bit, and arrange for "async_restart"
3102 			 * to be called in 1/4 second; it will turn the
3103 			 * break bit off, and call "async_start" to grab
3104 			 * the next message.
3105 			 */
3106 			mutex_enter(&asy->asy_excl_hi);
3107 			val = ddi_get8(asy->asy_iohandle,
3108 			    asy->asy_ioaddr + LCR);
3109 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3110 			    (val | SETBREAK));
3111 			mutex_exit(&asy->asy_excl_hi);
3112 			async->async_flags |= ASYNC_BREAK;
3113 			(void) timeout(async_restart, (caddr_t)async,
3114 			    drv_usectohz(1000000)/4);
3115 			freemsg(bp);
3116 			return;	/* wait for this to finish */
3117 
3118 		case M_DELAY:
3119 			/*
3120 			 * Arrange for "async_restart" to be called when the
3121 			 * delay expires; it will turn ASYNC_DELAY off,
3122 			 * and call "async_start" to grab the next message.
3123 			 */
3124 			(void) timeout(async_restart, (caddr_t)async,
3125 			    (int)(*(unsigned char *)bp->b_rptr + 6));
3126 			async->async_flags |= ASYNC_DELAY;
3127 			freemsg(bp);
3128 			return;	/* wait for this to finish */
3129 
3130 		case M_IOCTL:
3131 			/*
3132 			 * This ioctl was waiting for the output ahead of
3133 			 * it to drain; obviously, it has.  Do it, and
3134 			 * then grab the next message after it.
3135 			 */
3136 			mutex_exit(&asy->asy_excl);
3137 			async_ioctl(async, q, bp);
3138 			mutex_enter(&asy->asy_excl);
3139 			continue;
3140 		}
3141 
3142 		while (bp != NULL && ((cc = MBLKL(bp)) == 0)) {
3143 			nbp = bp->b_cont;
3144 			freeb(bp);
3145 			bp = nbp;
3146 		}
3147 		if (bp != NULL)
3148 			break;
3149 	}
3150 
3151 	/*
3152 	 * We have data to transmit.  If output is stopped, put
3153 	 * it back and try again later.
3154 	 */
3155 	if (async->async_flags & (ASYNC_HW_OUT_FLW | ASYNC_SW_OUT_FLW |
3156 	    ASYNC_STOPPED | ASYNC_OUT_SUSPEND)) {
3157 		(void) putbq(q, bp);
3158 		return;
3159 	}
3160 
3161 	async->async_xmitblk = bp;
3162 	xmit_addr = bp->b_rptr;
3163 	bp = bp->b_cont;
3164 	if (bp != NULL)
3165 		(void) putbq(q, bp);	/* not done with this message yet */
3166 
3167 	/*
3168 	 * In 5-bit mode, the high order bits are used
3169 	 * to indicate character sizes less than five,
3170 	 * so we need to explicitly mask before transmitting
3171 	 */
3172 	if ((async->async_ttycommon.t_cflag & CSIZE) == CS5) {
3173 		unsigned char *p = xmit_addr;
3174 		int cnt = cc;
3175 
3176 		while (cnt--)
3177 			*p++ &= (unsigned char) 0x1f;
3178 	}
3179 
3180 	/*
3181 	 * Set up this block for pseudo-DMA.
3182 	 */
3183 	mutex_enter(&asy->asy_excl_hi);
3184 	/*
3185 	 * If the transmitter is ready, shove the first
3186 	 * character out.
3187 	 */
3188 	didsome = B_FALSE;
3189 	while (--fifo_len >= 0 && cc > 0) {
3190 		if (!(ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) &
3191 		    XHRE))
3192 			break;
3193 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
3194 		    *xmit_addr++);
3195 		cc--;
3196 		didsome = B_TRUE;
3197 	}
3198 	async->async_optr = xmit_addr;
3199 	async->async_ocnt = cc;
3200 	if (didsome)
3201 		async->async_flags |= ASYNC_PROGRESS;
3202 	DEBUGCONT2(ASY_DEBUG_BUSY,
3203 	    "async%d_nstart: Set ASYNC_BUSY.  async_ocnt=%d\n",
3204 	    instance, async->async_ocnt);
3205 	async->async_flags |= ASYNC_BUSY;
3206 	mutex_exit(&asy->asy_excl_hi);
3207 }
3208 
3209 /*
3210  * Resume output by poking the transmitter.
3211  */
3212 static void
3213 async_resume(struct asyncline *async)
3214 {
3215 	struct asycom *asy = async->async_common;
3216 #ifdef DEBUG
3217 	int instance;
3218 #endif
3219 
3220 	ASSERT(mutex_owned(&asy->asy_excl_hi));
3221 #ifdef DEBUG
3222 	instance = UNIT(async->async_dev);
3223 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_resume\n", instance);
3224 #endif
3225 
3226 	if (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE) {
3227 		if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
3228 			return;
3229 		if (async->async_ocnt > 0 &&
3230 		    !(async->async_flags &
3231 		    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_OUT_SUSPEND))) {
3232 			ddi_put8(asy->asy_iohandle,
3233 			    asy->asy_ioaddr + DAT, *async->async_optr++);
3234 			async->async_ocnt--;
3235 			async->async_flags |= ASYNC_PROGRESS;
3236 		}
3237 	}
3238 }
3239 
3240 /*
3241  * Hold the untimed break to last the minimum time.
3242  */
3243 static void
3244 async_hold_utbrk(void *arg)
3245 {
3246 	struct asyncline *async = arg;
3247 	struct asycom *asy = async->async_common;
3248 
3249 	mutex_enter(&asy->asy_excl);
3250 	async->async_flags &= ~ASYNC_HOLD_UTBRK;
3251 	cv_broadcast(&async->async_flags_cv);
3252 	async->async_utbrktid = 0;
3253 	mutex_exit(&asy->asy_excl);
3254 }
3255 
3256 /*
3257  * Resume the untimed break.
3258  */
3259 static void
3260 async_resume_utbrk(struct asyncline *async)
3261 {
3262 	uchar_t	val;
3263 	struct asycom *asy = async->async_common;
3264 	ASSERT(mutex_owned(&asy->asy_excl));
3265 
3266 	/*
3267 	 * Because the wait time is very short,
3268 	 * so we use uninterruptably wait.
3269 	 */
3270 	while (async->async_flags & ASYNC_HOLD_UTBRK) {
3271 		cv_wait(&async->async_flags_cv, &asy->asy_excl);
3272 	}
3273 	mutex_enter(&asy->asy_excl_hi);
3274 	/*
3275 	 * Timed break and untimed break can exist simultaneously,
3276 	 * if ASYNC_BREAK is also set at here, we don't
3277 	 * really clean the HW break.
3278 	 */
3279 	if (!(async->async_flags & ASYNC_BREAK)) {
3280 		val = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
3281 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3282 		    (val & ~SETBREAK));
3283 	}
3284 	async->async_flags &= ~ASYNC_OUT_SUSPEND;
3285 	cv_broadcast(&async->async_flags_cv);
3286 	if (async->async_ocnt > 0) {
3287 		async_resume(async);
3288 		mutex_exit(&asy->asy_excl_hi);
3289 	} else {
3290 		async->async_flags &= ~ASYNC_BUSY;
3291 		mutex_exit(&asy->asy_excl_hi);
3292 		if (async->async_xmitblk != NULL) {
3293 			freeb(async->async_xmitblk);
3294 			async->async_xmitblk = NULL;
3295 		}
3296 		async_start(async);
3297 	}
3298 }
3299 
3300 /*
3301  * Process an "ioctl" message sent down to us.
3302  * Note that we don't need to get any locks until we are ready to access
3303  * the hardware.  Nothing we access until then is going to be altered
3304  * outside of the STREAMS framework, so we should be safe.
3305  */
3306 int asydelay = 10000;
3307 static void
3308 async_ioctl(struct asyncline *async, queue_t *wq, mblk_t *mp)
3309 {
3310 	struct asycom *asy = async->async_common;
3311 	tty_common_t  *tp = &async->async_ttycommon;
3312 	struct iocblk *iocp;
3313 	unsigned datasize;
3314 	int error = 0;
3315 	uchar_t val;
3316 	mblk_t *datamp;
3317 	unsigned int index;
3318 
3319 #ifdef DEBUG
3320 	int instance = UNIT(async->async_dev);
3321 
3322 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl\n", instance);
3323 #endif
3324 
3325 	if (tp->t_iocpending != NULL) {
3326 		/*
3327 		 * We were holding an "ioctl" response pending the
3328 		 * availability of an "mblk" to hold data to be passed up;
3329 		 * another "ioctl" came through, which means that "ioctl"
3330 		 * must have timed out or been aborted.
3331 		 */
3332 		freemsg(async->async_ttycommon.t_iocpending);
3333 		async->async_ttycommon.t_iocpending = NULL;
3334 	}
3335 
3336 	iocp = (struct iocblk *)mp->b_rptr;
3337 
3338 	/*
3339 	 * For TIOCMGET and the PPS ioctls, do NOT call ttycommon_ioctl()
3340 	 * because this function frees up the message block (mp->b_cont) that
3341 	 * contains the user location where we pass back the results.
3342 	 *
3343 	 * Similarly, CONSOPENPOLLEDIO needs ioc_count, which ttycommon_ioctl
3344 	 * zaps.  We know that ttycommon_ioctl doesn't know any CONS*
3345 	 * ioctls, so keep the others safe too.
3346 	 */
3347 	DEBUGCONT2(ASY_DEBUG_IOCTL, "async%d_ioctl: %s\n",
3348 	    instance,
3349 	    iocp->ioc_cmd == TIOCMGET ? "TIOCMGET" :
3350 	    iocp->ioc_cmd == TIOCMSET ? "TIOCMSET" :
3351 	    iocp->ioc_cmd == TIOCMBIS ? "TIOCMBIS" :
3352 	    iocp->ioc_cmd == TIOCMBIC ? "TIOCMBIC" :
3353 	    "other");
3354 
3355 	switch (iocp->ioc_cmd) {
3356 	case TIOCMGET:
3357 	case TIOCGPPS:
3358 	case TIOCSPPS:
3359 	case TIOCGPPSEV:
3360 	case CONSOPENPOLLEDIO:
3361 	case CONSCLOSEPOLLEDIO:
3362 	case CONSSETABORTENABLE:
3363 	case CONSGETABORTENABLE:
3364 		error = -1; /* Do Nothing */
3365 		break;
3366 	default:
3367 
3368 		/*
3369 		 * The only way in which "ttycommon_ioctl" can fail is if the
3370 		 * "ioctl" requires a response containing data to be returned
3371 		 * to the user, and no mblk could be allocated for the data.
3372 		 * No such "ioctl" alters our state.  Thus, we always go ahead
3373 		 * and do any state-changes the "ioctl" calls for.  If we
3374 		 * couldn't allocate the data, "ttycommon_ioctl" has stashed
3375 		 * the "ioctl" away safely, so we just call "bufcall" to
3376 		 * request that we be called back when we stand a better
3377 		 * chance of allocating the data.
3378 		 */
3379 		if ((datasize = ttycommon_ioctl(tp, wq, mp, &error)) != 0) {
3380 			if (async->async_wbufcid)
3381 				unbufcall(async->async_wbufcid);
3382 			async->async_wbufcid = bufcall(datasize, BPRI_HI,
3383 			    (void (*)(void *)) async_reioctl,
3384 			    (void *)(intptr_t)async->async_common->asy_unit);
3385 			return;
3386 		}
3387 	}
3388 
3389 	mutex_enter(&asy->asy_excl);
3390 
3391 	if (error == 0) {
3392 		/*
3393 		 * "ttycommon_ioctl" did most of the work; we just use the
3394 		 * data it set up.
3395 		 */
3396 		switch (iocp->ioc_cmd) {
3397 
3398 		case TCSETS:
3399 			mutex_enter(&asy->asy_excl_hi);
3400 			if (asy_baudok(asy))
3401 				asy_program(asy, ASY_NOINIT);
3402 			else
3403 				error = EINVAL;
3404 			mutex_exit(&asy->asy_excl_hi);
3405 			break;
3406 		case TCSETSF:
3407 		case TCSETSW:
3408 		case TCSETA:
3409 		case TCSETAW:
3410 		case TCSETAF:
3411 			mutex_enter(&asy->asy_excl_hi);
3412 			if (!asy_baudok(asy))
3413 				error = EINVAL;
3414 			else {
3415 				if (asy_isbusy(asy))
3416 					asy_waiteot(asy);
3417 				asy_program(asy, ASY_NOINIT);
3418 			}
3419 			mutex_exit(&asy->asy_excl_hi);
3420 			break;
3421 		}
3422 	} else if (error < 0) {
3423 		/*
3424 		 * "ttycommon_ioctl" didn't do anything; we process it here.
3425 		 */
3426 		error = 0;
3427 		switch (iocp->ioc_cmd) {
3428 
3429 		case TIOCGPPS:
3430 			/*
3431 			 * Get PPS on/off.
3432 			 */
3433 			if (mp->b_cont != NULL)
3434 				freemsg(mp->b_cont);
3435 
3436 			mp->b_cont = allocb(sizeof (int), BPRI_HI);
3437 			if (mp->b_cont == NULL) {
3438 				error = ENOMEM;
3439 				break;
3440 			}
3441 			if (asy->asy_flags & ASY_PPS)
3442 				*(int *)mp->b_cont->b_wptr = 1;
3443 			else
3444 				*(int *)mp->b_cont->b_wptr = 0;
3445 			mp->b_cont->b_wptr += sizeof (int);
3446 			mp->b_datap->db_type = M_IOCACK;
3447 			iocp->ioc_count = sizeof (int);
3448 			break;
3449 
3450 		case TIOCSPPS:
3451 			/*
3452 			 * Set PPS on/off.
3453 			 */
3454 			error = miocpullup(mp, sizeof (int));
3455 			if (error != 0)
3456 				break;
3457 
3458 			mutex_enter(&asy->asy_excl_hi);
3459 			if (*(int *)mp->b_cont->b_rptr)
3460 				asy->asy_flags |= ASY_PPS;
3461 			else
3462 				asy->asy_flags &= ~ASY_PPS;
3463 			/* Reset edge sense */
3464 			asy->asy_flags &= ~ASY_PPS_EDGE;
3465 			mutex_exit(&asy->asy_excl_hi);
3466 			mp->b_datap->db_type = M_IOCACK;
3467 			break;
3468 
3469 		case TIOCGPPSEV:
3470 		{
3471 			/*
3472 			 * Get PPS event data.
3473 			 */
3474 			mblk_t *bp;
3475 			void *buf;
3476 #ifdef _SYSCALL32_IMPL
3477 			struct ppsclockev32 p32;
3478 #endif
3479 			struct ppsclockev ppsclockev;
3480 
3481 			if (mp->b_cont != NULL) {
3482 				freemsg(mp->b_cont);
3483 				mp->b_cont = NULL;
3484 			}
3485 
3486 			if ((asy->asy_flags & ASY_PPS) == 0) {
3487 				error = ENXIO;
3488 				break;
3489 			}
3490 
3491 			/* Protect from incomplete asy_ppsev */
3492 			mutex_enter(&asy->asy_excl_hi);
3493 			ppsclockev = asy_ppsev;
3494 			mutex_exit(&asy->asy_excl_hi);
3495 
3496 #ifdef _SYSCALL32_IMPL
3497 			if ((iocp->ioc_flag & IOC_MODELS) != IOC_NATIVE) {
3498 				TIMEVAL_TO_TIMEVAL32(&p32.tv, &ppsclockev.tv);
3499 				p32.serial = ppsclockev.serial;
3500 				buf = &p32;
3501 				iocp->ioc_count = sizeof (struct ppsclockev32);
3502 			} else
3503 #endif
3504 			{
3505 				buf = &ppsclockev;
3506 				iocp->ioc_count = sizeof (struct ppsclockev);
3507 			}
3508 
3509 			if ((bp = allocb(iocp->ioc_count, BPRI_HI)) == NULL) {
3510 				error = ENOMEM;
3511 				break;
3512 			}
3513 			mp->b_cont = bp;
3514 
3515 			bcopy(buf, bp->b_wptr, iocp->ioc_count);
3516 			bp->b_wptr += iocp->ioc_count;
3517 			mp->b_datap->db_type = M_IOCACK;
3518 			break;
3519 		}
3520 
3521 		case TCSBRK:
3522 			error = miocpullup(mp, sizeof (int));
3523 			if (error != 0)
3524 				break;
3525 
3526 			if (*(int *)mp->b_cont->b_rptr == 0) {
3527 
3528 				/*
3529 				 * XXX Arrangements to ensure that a break
3530 				 * isn't in progress should be sufficient.
3531 				 * This ugly delay() is the only thing
3532 				 * that seems to work on the NCR Worldmark.
3533 				 * It should be replaced. Note that an
3534 				 * asy_waiteot() also does not work.
3535 				 */
3536 				if (asydelay)
3537 					delay(drv_usectohz(asydelay));
3538 
3539 				while (async->async_flags & ASYNC_BREAK) {
3540 					cv_wait(&async->async_flags_cv,
3541 					    &asy->asy_excl);
3542 				}
3543 				mutex_enter(&asy->asy_excl_hi);
3544 				/*
3545 				 * We loop until the TSR is empty and then
3546 				 * set the break.  ASYNC_BREAK has been set
3547 				 * to ensure that no characters are
3548 				 * transmitted while the TSR is being
3549 				 * flushed and SOUT is being used for the
3550 				 * break signal.
3551 				 *
3552 				 * The wait period is equal to
3553 				 * clock / (baud * 16) * 16 * 2.
3554 				 */
3555 				index = BAUDINDEX(
3556 				    async->async_ttycommon.t_cflag);
3557 				async->async_flags |= ASYNC_BREAK;
3558 
3559 				while ((ddi_get8(asy->asy_iohandle,
3560 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3561 					mutex_exit(&asy->asy_excl_hi);
3562 					mutex_exit(&asy->asy_excl);
3563 					drv_usecwait(
3564 					    32*asyspdtab[index] & 0xfff);
3565 					mutex_enter(&asy->asy_excl);
3566 					mutex_enter(&asy->asy_excl_hi);
3567 				}
3568 				/*
3569 				 * Arrange for "async_restart"
3570 				 * to be called in 1/4 second;
3571 				 * it will turn the break bit off, and call
3572 				 * "async_start" to grab the next message.
3573 				 */
3574 				val = ddi_get8(asy->asy_iohandle,
3575 				    asy->asy_ioaddr + LCR);
3576 				ddi_put8(asy->asy_iohandle,
3577 				    asy->asy_ioaddr + LCR,
3578 				    (val | SETBREAK));
3579 				mutex_exit(&asy->asy_excl_hi);
3580 				(void) timeout(async_restart, (caddr_t)async,
3581 				    drv_usectohz(1000000)/4);
3582 			} else {
3583 				DEBUGCONT1(ASY_DEBUG_OUT,
3584 				    "async%d_ioctl: wait for flush.\n",
3585 				    instance);
3586 				mutex_enter(&asy->asy_excl_hi);
3587 				asy_waiteot(asy);
3588 				mutex_exit(&asy->asy_excl_hi);
3589 				DEBUGCONT1(ASY_DEBUG_OUT,
3590 				    "async%d_ioctl: ldterm satisfied.\n",
3591 				    instance);
3592 			}
3593 			break;
3594 
3595 		case TIOCSBRK:
3596 			if (!(async->async_flags & ASYNC_OUT_SUSPEND)) {
3597 				mutex_enter(&asy->asy_excl_hi);
3598 				async->async_flags |= ASYNC_OUT_SUSPEND;
3599 				async->async_flags |= ASYNC_HOLD_UTBRK;
3600 				index = BAUDINDEX(
3601 				    async->async_ttycommon.t_cflag);
3602 				while ((ddi_get8(asy->asy_iohandle,
3603 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3604 					mutex_exit(&asy->asy_excl_hi);
3605 					mutex_exit(&asy->asy_excl);
3606 					drv_usecwait(
3607 					    32*asyspdtab[index] & 0xfff);
3608 					mutex_enter(&asy->asy_excl);
3609 					mutex_enter(&asy->asy_excl_hi);
3610 				}
3611 				val = ddi_get8(asy->asy_iohandle,
3612 				    asy->asy_ioaddr + LCR);
3613 				ddi_put8(asy->asy_iohandle,
3614 				    asy->asy_ioaddr + LCR, (val | SETBREAK));
3615 				mutex_exit(&asy->asy_excl_hi);
3616 				/* wait for 100ms to hold BREAK */
3617 				async->async_utbrktid =
3618 				    timeout((void (*)())async_hold_utbrk,
3619 				    (caddr_t)async,
3620 				    drv_usectohz(asy_min_utbrk));
3621 			}
3622 			mioc2ack(mp, NULL, 0, 0);
3623 			break;
3624 
3625 		case TIOCCBRK:
3626 			if (async->async_flags & ASYNC_OUT_SUSPEND)
3627 				async_resume_utbrk(async);
3628 			mioc2ack(mp, NULL, 0, 0);
3629 			break;
3630 
3631 		case TIOCMSET:
3632 		case TIOCMBIS:
3633 		case TIOCMBIC:
3634 			if (iocp->ioc_count != TRANSPARENT) {
3635 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3636 				    "non-transparent\n", instance);
3637 
3638 				error = miocpullup(mp, sizeof (int));
3639 				if (error != 0)
3640 					break;
3641 
3642 				mutex_enter(&asy->asy_excl_hi);
3643 				(void) asymctl(asy,
3644 				    dmtoasy(*(int *)mp->b_cont->b_rptr),
3645 				    iocp->ioc_cmd);
3646 				mutex_exit(&asy->asy_excl_hi);
3647 				iocp->ioc_error = 0;
3648 				mp->b_datap->db_type = M_IOCACK;
3649 			} else {
3650 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3651 				    "transparent\n", instance);
3652 				mcopyin(mp, NULL, sizeof (int), NULL);
3653 			}
3654 			break;
3655 
3656 		case TIOCMGET:
3657 			datamp = allocb(sizeof (int), BPRI_MED);
3658 			if (datamp == NULL) {
3659 				error = EAGAIN;
3660 				break;
3661 			}
3662 
3663 			mutex_enter(&asy->asy_excl_hi);
3664 			*(int *)datamp->b_rptr = asymctl(asy, 0, TIOCMGET);
3665 			mutex_exit(&asy->asy_excl_hi);
3666 
3667 			if (iocp->ioc_count == TRANSPARENT) {
3668 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3669 				    "transparent\n", instance);
3670 				mcopyout(mp, NULL, sizeof (int), NULL, datamp);
3671 			} else {
3672 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3673 				    "non-transparent\n", instance);
3674 				mioc2ack(mp, datamp, sizeof (int), 0);
3675 			}
3676 			break;
3677 
3678 		case CONSOPENPOLLEDIO:
3679 			error = miocpullup(mp, sizeof (struct cons_polledio *));
3680 			if (error != 0)
3681 				break;
3682 
3683 			*(struct cons_polledio **)mp->b_cont->b_rptr =
3684 			    &asy->polledio;
3685 
3686 			mp->b_datap->db_type = M_IOCACK;
3687 			break;
3688 
3689 		case CONSCLOSEPOLLEDIO:
3690 			mp->b_datap->db_type = M_IOCACK;
3691 			iocp->ioc_error = 0;
3692 			iocp->ioc_rval = 0;
3693 			break;
3694 
3695 		case CONSSETABORTENABLE:
3696 			error = secpolicy_console(iocp->ioc_cr);
3697 			if (error != 0)
3698 				break;
3699 
3700 			if (iocp->ioc_count != TRANSPARENT) {
3701 				error = EINVAL;
3702 				break;
3703 			}
3704 
3705 			if (*(intptr_t *)mp->b_cont->b_rptr)
3706 				asy->asy_flags |= ASY_CONSOLE;
3707 			else
3708 				asy->asy_flags &= ~ASY_CONSOLE;
3709 
3710 			mp->b_datap->db_type = M_IOCACK;
3711 			iocp->ioc_error = 0;
3712 			iocp->ioc_rval = 0;
3713 			break;
3714 
3715 		case CONSGETABORTENABLE:
3716 			/*CONSTANTCONDITION*/
3717 			ASSERT(sizeof (boolean_t) <= sizeof (boolean_t *));
3718 			/*
3719 			 * Store the return value right in the payload
3720 			 * we were passed.  Crude.
3721 			 */
3722 			mcopyout(mp, NULL, sizeof (boolean_t), NULL, NULL);
3723 			*(boolean_t *)mp->b_cont->b_rptr =
3724 			    (asy->asy_flags & ASY_CONSOLE) != 0;
3725 			break;
3726 
3727 		default:
3728 			/*
3729 			 * If we don't understand it, it's an error.  NAK it.
3730 			 */
3731 			error = EINVAL;
3732 			break;
3733 		}
3734 	}
3735 	if (error != 0) {
3736 		iocp->ioc_error = error;
3737 		mp->b_datap->db_type = M_IOCNAK;
3738 	}
3739 	mutex_exit(&asy->asy_excl);
3740 	qreply(wq, mp);
3741 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl: done\n", instance);
3742 }
3743 
3744 static int
3745 asyrsrv(queue_t *q)
3746 {
3747 	mblk_t *bp;
3748 	struct asyncline *async;
3749 
3750 	async = (struct asyncline *)q->q_ptr;
3751 
3752 	while (canputnext(q) && (bp = getq(q)))
3753 		putnext(q, bp);
3754 	ASYSETSOFT(async->async_common);
3755 	async->async_polltid = 0;
3756 	return (0);
3757 }
3758 
3759 /*
3760  * The ASYWPUTDO_NOT_SUSP macro indicates to asywputdo() whether it should
3761  * handle messages as though the driver is operating normally or is
3762  * suspended.  In the suspended case, some or all of the processing may have
3763  * to be delayed until the driver is resumed.
3764  */
3765 #define	ASYWPUTDO_NOT_SUSP(async, wput) \
3766 	!((wput) && ((async)->async_flags & ASYNC_DDI_SUSPENDED))
3767 
3768 /*
3769  * Processing for write queue put procedure.
3770  * Respond to M_STOP, M_START, M_IOCTL, and M_FLUSH messages here;
3771  * set the flow control character for M_STOPI and M_STARTI messages;
3772  * queue up M_BREAK, M_DELAY, and M_DATA messages for processing
3773  * by the start routine, and then call the start routine; discard
3774  * everything else.  Note that this driver does not incorporate any
3775  * mechanism to negotiate to handle the canonicalization process.
3776  * It expects that these functions are handled in upper module(s),
3777  * as we do in ldterm.
3778  */
3779 static int
3780 asywputdo(queue_t *q, mblk_t *mp, boolean_t wput)
3781 {
3782 	struct asyncline *async;
3783 	struct asycom *asy;
3784 #ifdef DEBUG
3785 	int instance;
3786 #endif
3787 	int error;
3788 
3789 	async = (struct asyncline *)q->q_ptr;
3790 
3791 #ifdef DEBUG
3792 	instance = UNIT(async->async_dev);
3793 #endif
3794 	asy = async->async_common;
3795 
3796 	switch (mp->b_datap->db_type) {
3797 
3798 	case M_STOP:
3799 		/*
3800 		 * Since we don't do real DMA, we can just let the
3801 		 * chip coast to a stop after applying the brakes.
3802 		 */
3803 		mutex_enter(&asy->asy_excl);
3804 		async->async_flags |= ASYNC_STOPPED;
3805 		mutex_exit(&asy->asy_excl);
3806 		freemsg(mp);
3807 		break;
3808 
3809 	case M_START:
3810 		mutex_enter(&asy->asy_excl);
3811 		if (async->async_flags & ASYNC_STOPPED) {
3812 			async->async_flags &= ~ASYNC_STOPPED;
3813 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3814 				/*
3815 				 * If an output operation is in progress,
3816 				 * resume it.  Otherwise, prod the start
3817 				 * routine.
3818 				 */
3819 				if (async->async_ocnt > 0) {
3820 					mutex_enter(&asy->asy_excl_hi);
3821 					async_resume(async);
3822 					mutex_exit(&asy->asy_excl_hi);
3823 				} else {
3824 					async_start(async);
3825 				}
3826 			}
3827 		}
3828 		mutex_exit(&asy->asy_excl);
3829 		freemsg(mp);
3830 		break;
3831 
3832 	case M_IOCTL:
3833 		switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
3834 
3835 		case TCSBRK:
3836 			error = miocpullup(mp, sizeof (int));
3837 			if (error != 0) {
3838 				miocnak(q, mp, 0, error);
3839 				return (0);
3840 			}
3841 
3842 			if (*(int *)mp->b_cont->b_rptr != 0) {
3843 				DEBUGCONT1(ASY_DEBUG_OUT,
3844 				    "async%d_ioctl: flush request.\n",
3845 				    instance);
3846 				(void) putq(q, mp);
3847 
3848 				mutex_enter(&asy->asy_excl);
3849 				if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3850 					/*
3851 					 * If an TIOCSBRK is in progress,
3852 					 * clean it as TIOCCBRK does,
3853 					 * then kick off output.
3854 					 * If TIOCSBRK is not in progress,
3855 					 * just kick off output.
3856 					 */
3857 					async_resume_utbrk(async);
3858 				}
3859 				mutex_exit(&asy->asy_excl);
3860 				break;
3861 			}
3862 			/*FALLTHROUGH*/
3863 		case TCSETSW:
3864 		case TCSETSF:
3865 		case TCSETAW:
3866 		case TCSETAF:
3867 			/*
3868 			 * The changes do not take effect until all
3869 			 * output queued before them is drained.
3870 			 * Put this message on the queue, so that
3871 			 * "async_start" will see it when it's done
3872 			 * with the output before it.  Poke the
3873 			 * start routine, just in case.
3874 			 */
3875 			(void) putq(q, mp);
3876 
3877 			mutex_enter(&asy->asy_excl);
3878 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3879 				/*
3880 				 * If an TIOCSBRK is in progress,
3881 				 * clean it as TIOCCBRK does.
3882 				 * then kick off output.
3883 				 * If TIOCSBRK is not in progress,
3884 				 * just kick off output.
3885 				 */
3886 				async_resume_utbrk(async);
3887 			}
3888 			mutex_exit(&asy->asy_excl);
3889 			break;
3890 
3891 		default:
3892 			/*
3893 			 * Do it now.
3894 			 */
3895 			mutex_enter(&asy->asy_excl);
3896 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3897 				mutex_exit(&asy->asy_excl);
3898 				async_ioctl(async, q, mp);
3899 				break;
3900 			}
3901 			async_put_suspq(asy, mp);
3902 			mutex_exit(&asy->asy_excl);
3903 			break;
3904 		}
3905 		break;
3906 
3907 	case M_FLUSH:
3908 		if (*mp->b_rptr & FLUSHW) {
3909 			mutex_enter(&asy->asy_excl);
3910 
3911 			/*
3912 			 * Abort any output in progress.
3913 			 */
3914 			mutex_enter(&asy->asy_excl_hi);
3915 			if (async->async_flags & ASYNC_BUSY) {
3916 				DEBUGCONT1(ASY_DEBUG_BUSY, "asy%dwput: "
3917 				    "Clearing async_ocnt, "
3918 				    "leaving ASYNC_BUSY set\n",
3919 				    instance);
3920 				async->async_ocnt = 0;
3921 				async->async_flags &= ~ASYNC_BUSY;
3922 			} /* if */
3923 
3924 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3925 				/* Flush FIFO buffers */
3926 				if (asy->asy_use_fifo == FIFO_ON) {
3927 					asy_reset_fifo(asy, FIFOTXFLSH);
3928 				}
3929 			}
3930 			mutex_exit(&asy->asy_excl_hi);
3931 
3932 			/* Flush FIFO buffers */
3933 			if (asy->asy_use_fifo == FIFO_ON) {
3934 				asy_reset_fifo(asy, FIFOTXFLSH);
3935 			}
3936 
3937 			/*
3938 			 * Flush our write queue.
3939 			 */
3940 			flushq(q, FLUSHDATA);	/* XXX doesn't flush M_DELAY */
3941 			if (async->async_xmitblk != NULL) {
3942 				freeb(async->async_xmitblk);
3943 				async->async_xmitblk = NULL;
3944 			}
3945 			mutex_exit(&asy->asy_excl);
3946 			*mp->b_rptr &= ~FLUSHW;	/* it has been flushed */
3947 		}
3948 		if (*mp->b_rptr & FLUSHR) {
3949 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3950 				/* Flush FIFO buffers */
3951 				if (asy->asy_use_fifo == FIFO_ON) {
3952 					asy_reset_fifo(asy, FIFORXFLSH);
3953 				}
3954 			}
3955 			flushq(RD(q), FLUSHDATA);
3956 			qreply(q, mp);	/* give the read queues a crack at it */
3957 		} else {
3958 			freemsg(mp);
3959 		}
3960 
3961 		/*
3962 		 * We must make sure we process messages that survive the
3963 		 * write-side flush.
3964 		 */
3965 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3966 			mutex_enter(&asy->asy_excl);
3967 			async_start(async);
3968 			mutex_exit(&asy->asy_excl);
3969 		}
3970 		break;
3971 
3972 	case M_BREAK:
3973 	case M_DELAY:
3974 	case M_DATA:
3975 		/*
3976 		 * Queue the message up to be transmitted,
3977 		 * and poke the start routine.
3978 		 */
3979 		(void) putq(q, mp);
3980 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3981 			mutex_enter(&asy->asy_excl);
3982 			async_start(async);
3983 			mutex_exit(&asy->asy_excl);
3984 		}
3985 		break;
3986 
3987 	case M_STOPI:
3988 		mutex_enter(&asy->asy_excl);
3989 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3990 			mutex_enter(&asy->asy_excl_hi);
3991 			if (!(async->async_inflow_source & IN_FLOW_USER)) {
3992 				async_flowcontrol_hw_input(asy, FLOW_STOP,
3993 				    IN_FLOW_USER);
3994 				(void) async_flowcontrol_sw_input(asy,
3995 				    FLOW_STOP, IN_FLOW_USER);
3996 			}
3997 			mutex_exit(&asy->asy_excl_hi);
3998 			mutex_exit(&asy->asy_excl);
3999 			freemsg(mp);
4000 			break;
4001 		}
4002 		async_put_suspq(asy, mp);
4003 		mutex_exit(&asy->asy_excl);
4004 		break;
4005 
4006 	case M_STARTI:
4007 		mutex_enter(&asy->asy_excl);
4008 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4009 			mutex_enter(&asy->asy_excl_hi);
4010 			if (async->async_inflow_source & IN_FLOW_USER) {
4011 				async_flowcontrol_hw_input(asy, FLOW_START,
4012 				    IN_FLOW_USER);
4013 				(void) async_flowcontrol_sw_input(asy,
4014 				    FLOW_START, IN_FLOW_USER);
4015 			}
4016 			mutex_exit(&asy->asy_excl_hi);
4017 			mutex_exit(&asy->asy_excl);
4018 			freemsg(mp);
4019 			break;
4020 		}
4021 		async_put_suspq(asy, mp);
4022 		mutex_exit(&asy->asy_excl);
4023 		break;
4024 
4025 	case M_CTL:
4026 		if (MBLKL(mp) >= sizeof (struct iocblk) &&
4027 		    ((struct iocblk *)mp->b_rptr)->ioc_cmd == MC_POSIXQUERY) {
4028 			mutex_enter(&asy->asy_excl);
4029 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4030 				((struct iocblk *)mp->b_rptr)->ioc_cmd =
4031 				    MC_HAS_POSIX;
4032 				mutex_exit(&asy->asy_excl);
4033 				qreply(q, mp);
4034 				break;
4035 			} else {
4036 				async_put_suspq(asy, mp);
4037 			}
4038 		} else {
4039 			/*
4040 			 * These MC_SERVICE type messages are used by upper
4041 			 * modules to tell this driver to send input up
4042 			 * immediately, or that it can wait for normal
4043 			 * processing that may or may not be done.  Sun
4044 			 * requires these for the mouse module.
4045 			 * (XXX - for x86?)
4046 			 */
4047 			mutex_enter(&asy->asy_excl);
4048 			switch (*mp->b_rptr) {
4049 
4050 			case MC_SERVICEIMM:
4051 				async->async_flags |= ASYNC_SERVICEIMM;
4052 				break;
4053 
4054 			case MC_SERVICEDEF:
4055 				async->async_flags &= ~ASYNC_SERVICEIMM;
4056 				break;
4057 			}
4058 			mutex_exit(&asy->asy_excl);
4059 			freemsg(mp);
4060 		}
4061 		break;
4062 
4063 	case M_IOCDATA:
4064 		mutex_enter(&asy->asy_excl);
4065 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4066 			mutex_exit(&asy->asy_excl);
4067 			async_iocdata(q, mp);
4068 			break;
4069 		}
4070 		async_put_suspq(asy, mp);
4071 		mutex_exit(&asy->asy_excl);
4072 		break;
4073 
4074 	default:
4075 		freemsg(mp);
4076 		break;
4077 	}
4078 	return (0);
4079 }
4080 
4081 static int
4082 asywput(queue_t *q, mblk_t *mp)
4083 {
4084 	return (asywputdo(q, mp, B_TRUE));
4085 }
4086 
4087 /*
4088  * Retry an "ioctl", now that "bufcall" claims we may be able to allocate
4089  * the buffer we need.
4090  */
4091 static void
4092 async_reioctl(void *unit)
4093 {
4094 	int instance = (uintptr_t)unit;
4095 	struct asyncline *async;
4096 	struct asycom *asy;
4097 	queue_t	*q;
4098 	mblk_t	*mp;
4099 
4100 	asy = ddi_get_soft_state(asy_soft_state, instance);
4101 	ASSERT(asy != NULL);
4102 	async = asy->asy_priv;
4103 
4104 	/*
4105 	 * The bufcall is no longer pending.
4106 	 */
4107 	mutex_enter(&asy->asy_excl);
4108 	async->async_wbufcid = 0;
4109 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
4110 		mutex_exit(&asy->asy_excl);
4111 		return;
4112 	}
4113 	if ((mp = async->async_ttycommon.t_iocpending) != NULL) {
4114 		/* not pending any more */
4115 		async->async_ttycommon.t_iocpending = NULL;
4116 		mutex_exit(&asy->asy_excl);
4117 		async_ioctl(async, q, mp);
4118 	} else
4119 		mutex_exit(&asy->asy_excl);
4120 }
4121 
4122 static void
4123 async_iocdata(queue_t *q, mblk_t *mp)
4124 {
4125 	struct asyncline	*async = (struct asyncline *)q->q_ptr;
4126 	struct asycom		*asy;
4127 	struct iocblk *ip;
4128 	struct copyresp *csp;
4129 #ifdef DEBUG
4130 	int instance = UNIT(async->async_dev);
4131 #endif
4132 
4133 	asy = async->async_common;
4134 	ip = (struct iocblk *)mp->b_rptr;
4135 	csp = (struct copyresp *)mp->b_rptr;
4136 
4137 	if (csp->cp_rval != 0) {
4138 		if (csp->cp_private)
4139 			freemsg(csp->cp_private);
4140 		freemsg(mp);
4141 		return;
4142 	}
4143 
4144 	mutex_enter(&asy->asy_excl);
4145 	DEBUGCONT2(ASY_DEBUG_MODEM, "async%d_iocdata: case %s\n",
4146 	    instance,
4147 	    csp->cp_cmd == TIOCMGET ? "TIOCMGET" :
4148 	    csp->cp_cmd == TIOCMSET ? "TIOCMSET" :
4149 	    csp->cp_cmd == TIOCMBIS ? "TIOCMBIS" :
4150 	    "TIOCMBIC");
4151 	switch (csp->cp_cmd) {
4152 
4153 	case TIOCMGET:
4154 		if (mp->b_cont) {
4155 			freemsg(mp->b_cont);
4156 			mp->b_cont = NULL;
4157 		}
4158 		mp->b_datap->db_type = M_IOCACK;
4159 		ip->ioc_error = 0;
4160 		ip->ioc_count = 0;
4161 		ip->ioc_rval = 0;
4162 		mp->b_wptr = mp->b_rptr + sizeof (struct iocblk);
4163 		break;
4164 
4165 	case TIOCMSET:
4166 	case TIOCMBIS:
4167 	case TIOCMBIC:
4168 		mutex_enter(&asy->asy_excl_hi);
4169 		(void) asymctl(asy, dmtoasy(*(int *)mp->b_cont->b_rptr),
4170 		    csp->cp_cmd);
4171 		mutex_exit(&asy->asy_excl_hi);
4172 		mioc2ack(mp, NULL, 0, 0);
4173 		break;
4174 
4175 	default:
4176 		mp->b_datap->db_type = M_IOCNAK;
4177 		ip->ioc_error = EINVAL;
4178 		break;
4179 	}
4180 	qreply(q, mp);
4181 	mutex_exit(&asy->asy_excl);
4182 }
4183 
4184 /*
4185  * debugger/console support routines.
4186  */
4187 
4188 /*
4189  * put a character out
4190  * Do not use interrupts.  If char is LF, put out CR, LF.
4191  */
4192 static void
4193 asyputchar(cons_polledio_arg_t arg, uchar_t c)
4194 {
4195 	struct asycom *asy = (struct asycom *)arg;
4196 
4197 	if (c == '\n')
4198 		asyputchar(arg, '\r');
4199 
4200 	while ((ddi_get8(asy->asy_iohandle,
4201 	    asy->asy_ioaddr + LSR) & XHRE) == 0) {
4202 		/* wait for xmit to finish */
4203 		drv_usecwait(10);
4204 	}
4205 
4206 	/* put the character out */
4207 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT, c);
4208 }
4209 
4210 /*
4211  * See if there's a character available. If no character is
4212  * available, return 0. Run in polled mode, no interrupts.
4213  */
4214 static boolean_t
4215 asyischar(cons_polledio_arg_t arg)
4216 {
4217 	struct asycom *asy = (struct asycom *)arg;
4218 
4219 	return ((ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & RCA)
4220 	    != 0);
4221 }
4222 
4223 /*
4224  * Get a character. Run in polled mode, no interrupts.
4225  */
4226 static int
4227 asygetchar(cons_polledio_arg_t arg)
4228 {
4229 	struct asycom *asy = (struct asycom *)arg;
4230 
4231 	while (!asyischar(arg))
4232 		drv_usecwait(10);
4233 	return (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + DAT));
4234 }
4235 
4236 /*
4237  * Set or get the modem control status.
4238  */
4239 static int
4240 asymctl(struct asycom *asy, int bits, int how)
4241 {
4242 	int mcr_r, msr_r;
4243 	int instance = asy->asy_unit;
4244 
4245 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4246 	ASSERT(mutex_owned(&asy->asy_excl));
4247 
4248 	/* Read Modem Control Registers */
4249 	mcr_r = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4250 
4251 	switch (how) {
4252 
4253 	case TIOCMSET:
4254 		DEBUGCONT2(ASY_DEBUG_MODEM,
4255 		    "asy%dmctl: TIOCMSET, bits = %x\n", instance, bits);
4256 		mcr_r = bits;		/* Set bits	*/
4257 		break;
4258 
4259 	case TIOCMBIS:
4260 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIS, bits = %x\n",
4261 		    instance, bits);
4262 		mcr_r |= bits;		/* Mask in bits	*/
4263 		break;
4264 
4265 	case TIOCMBIC:
4266 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIC, bits = %x\n",
4267 		    instance, bits);
4268 		mcr_r &= ~bits;		/* Mask out bits */
4269 		break;
4270 
4271 	case TIOCMGET:
4272 		/* Read Modem Status Registers */
4273 		/*
4274 		 * If modem interrupts are enabled, we return the
4275 		 * saved value of msr. We read MSR only in async_msint()
4276 		 */
4277 		if (ddi_get8(asy->asy_iohandle,
4278 		    asy->asy_ioaddr + ICR) & MIEN) {
4279 			msr_r = asy->asy_msr;
4280 			DEBUGCONT2(ASY_DEBUG_MODEM,
4281 			    "asy%dmctl: TIOCMGET, read msr_r = %x\n",
4282 			    instance, msr_r);
4283 		} else {
4284 			msr_r = ddi_get8(asy->asy_iohandle,
4285 			    asy->asy_ioaddr + MSR);
4286 			DEBUGCONT2(ASY_DEBUG_MODEM,
4287 			    "asy%dmctl: TIOCMGET, read MSR = %x\n",
4288 			    instance, msr_r);
4289 		}
4290 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dtodm: modem_lines = %x\n",
4291 		    instance, asytodm(mcr_r, msr_r));
4292 		return (asytodm(mcr_r, msr_r));
4293 	}
4294 
4295 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr_r);
4296 
4297 	return (mcr_r);
4298 }
4299 
4300 static int
4301 asytodm(int mcr_r, int msr_r)
4302 {
4303 	int b = 0;
4304 
4305 	/* MCR registers */
4306 	if (mcr_r & RTS)
4307 		b |= TIOCM_RTS;
4308 
4309 	if (mcr_r & DTR)
4310 		b |= TIOCM_DTR;
4311 
4312 	/* MSR registers */
4313 	if (msr_r & DCD)
4314 		b |= TIOCM_CAR;
4315 
4316 	if (msr_r & CTS)
4317 		b |= TIOCM_CTS;
4318 
4319 	if (msr_r & DSR)
4320 		b |= TIOCM_DSR;
4321 
4322 	if (msr_r & RI)
4323 		b |= TIOCM_RNG;
4324 	return (b);
4325 }
4326 
4327 static int
4328 dmtoasy(int bits)
4329 {
4330 	int b = 0;
4331 
4332 	DEBUGCONT1(ASY_DEBUG_MODEM, "dmtoasy: bits = %x\n", bits);
4333 #ifdef	CAN_NOT_SET	/* only DTR and RTS can be set */
4334 	if (bits & TIOCM_CAR)
4335 		b |= DCD;
4336 	if (bits & TIOCM_CTS)
4337 		b |= CTS;
4338 	if (bits & TIOCM_DSR)
4339 		b |= DSR;
4340 	if (bits & TIOCM_RNG)
4341 		b |= RI;
4342 #endif
4343 
4344 	if (bits & TIOCM_RTS) {
4345 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & RTS\n");
4346 		b |= RTS;
4347 	}
4348 	if (bits & TIOCM_DTR) {
4349 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & DTR\n");
4350 		b |= DTR;
4351 	}
4352 
4353 	return (b);
4354 }
4355 
4356 static void
4357 asyerror(int level, const char *fmt, ...)
4358 {
4359 	va_list adx;
4360 	static	time_t	last;
4361 	static	const char *lastfmt;
4362 	time_t	now;
4363 
4364 	/*
4365 	 * Don't print the same error message too often.
4366 	 * Print the message only if we have not printed the
4367 	 * message within the last second.
4368 	 * Note: that fmt cannot be a pointer to a string
4369 	 * stored on the stack. The fmt pointer
4370 	 * must be in the data segment otherwise lastfmt would point
4371 	 * to non-sense.
4372 	 */
4373 	now = gethrestime_sec();
4374 	if (last == now && lastfmt == fmt)
4375 		return;
4376 
4377 	last = now;
4378 	lastfmt = fmt;
4379 
4380 	va_start(adx, fmt);
4381 	vcmn_err(level, fmt, adx);
4382 	va_end(adx);
4383 }
4384 
4385 /*
4386  * asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4387  * The value of this property is in the form of "9600,8,n,1,-"
4388  * 1) speed: 9600, 4800, ...
4389  * 2) data bits
4390  * 3) parity: n(none), e(even), o(odd)
4391  * 4) stop bits
4392  * 5) handshake: -(none), h(hardware: rts/cts), s(software: xon/off)
4393  *
4394  * This parsing came from a SPARCstation eeprom.
4395  */
4396 static void
4397 asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4398 {
4399 	char		name[40];
4400 	char		val[40];
4401 	int		len;
4402 	int		ret;
4403 	char		*p;
4404 	char		*p1;
4405 
4406 	ASSERT(asy->asy_com_port != 0);
4407 
4408 	/*
4409 	 * Parse the ttyx-mode property
4410 	 */
4411 	(void) sprintf(name, "tty%c-mode", asy->asy_com_port + 'a' - 1);
4412 	len = sizeof (val);
4413 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4414 	if (ret != DDI_PROP_SUCCESS) {
4415 		(void) sprintf(name, "com%c-mode", asy->asy_com_port + '0');
4416 		len = sizeof (val);
4417 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4418 	}
4419 
4420 	/* no property to parse */
4421 	asy->asy_cflag = 0;
4422 	if (ret != DDI_PROP_SUCCESS)
4423 		return;
4424 
4425 	p = val;
4426 	/* ---- baud rate ---- */
4427 	asy->asy_cflag = CREAD|B9600;		/* initial default */
4428 	if (p && (p1 = strchr(p, ',')) != 0) {
4429 		*p1++ = '\0';
4430 	} else {
4431 		asy->asy_cflag |= BITS8;	/* add default bits */
4432 		return;
4433 	}
4434 
4435 	if (strcmp(p, "110") == 0)
4436 		asy->asy_bidx = B110;
4437 	else if (strcmp(p, "150") == 0)
4438 		asy->asy_bidx = B150;
4439 	else if (strcmp(p, "300") == 0)
4440 		asy->asy_bidx = B300;
4441 	else if (strcmp(p, "600") == 0)
4442 		asy->asy_bidx = B600;
4443 	else if (strcmp(p, "1200") == 0)
4444 		asy->asy_bidx = B1200;
4445 	else if (strcmp(p, "2400") == 0)
4446 		asy->asy_bidx = B2400;
4447 	else if (strcmp(p, "4800") == 0)
4448 		asy->asy_bidx = B4800;
4449 	else if (strcmp(p, "9600") == 0)
4450 		asy->asy_bidx = B9600;
4451 	else if (strcmp(p, "19200") == 0)
4452 		asy->asy_bidx = B19200;
4453 	else if (strcmp(p, "38400") == 0)
4454 		asy->asy_bidx = B38400;
4455 	else if (strcmp(p, "57600") == 0)
4456 		asy->asy_bidx = B57600;
4457 	else if (strcmp(p, "115200") == 0)
4458 		asy->asy_bidx = B115200;
4459 	else
4460 		asy->asy_bidx = B9600;
4461 
4462 	asy->asy_cflag &= ~CBAUD;
4463 	if (asy->asy_bidx > CBAUD) {	/* > 38400 uses the CBAUDEXT bit */
4464 		asy->asy_cflag |= CBAUDEXT;
4465 		asy->asy_cflag |= asy->asy_bidx - CBAUD - 1;
4466 	} else {
4467 		asy->asy_cflag |= asy->asy_bidx;
4468 	}
4469 
4470 	ASSERT(asy->asy_bidx == BAUDINDEX(asy->asy_cflag));
4471 
4472 	/* ---- Next item is data bits ---- */
4473 	p = p1;
4474 	if (p && (p1 = strchr(p, ',')) != 0)  {
4475 		*p1++ = '\0';
4476 	} else {
4477 		asy->asy_cflag |= BITS8;	/* add default bits */
4478 		return;
4479 	}
4480 	switch (*p) {
4481 		default:
4482 		case '8':
4483 			asy->asy_cflag |= CS8;
4484 			asy->asy_lcr = BITS8;
4485 			break;
4486 		case '7':
4487 			asy->asy_cflag |= CS7;
4488 			asy->asy_lcr = BITS7;
4489 			break;
4490 		case '6':
4491 			asy->asy_cflag |= CS6;
4492 			asy->asy_lcr = BITS6;
4493 			break;
4494 		case '5':
4495 			/* LINTED: CS5 is currently zero (but might change) */
4496 			asy->asy_cflag |= CS5;
4497 			asy->asy_lcr = BITS5;
4498 			break;
4499 	}
4500 
4501 	/* ---- Parity info ---- */
4502 	p = p1;
4503 	if (p && (p1 = strchr(p, ',')) != 0)  {
4504 		*p1++ = '\0';
4505 	} else {
4506 		return;
4507 	}
4508 	switch (*p)  {
4509 		default:
4510 		case 'n':
4511 			break;
4512 		case 'e':
4513 			asy->asy_cflag |= PARENB;
4514 			asy->asy_lcr |= PEN; break;
4515 		case 'o':
4516 			asy->asy_cflag |= PARENB|PARODD;
4517 			asy->asy_lcr |= PEN|EPS;
4518 			break;
4519 	}
4520 
4521 	/* ---- Find stop bits ---- */
4522 	p = p1;
4523 	if (p && (p1 = strchr(p, ',')) != 0)  {
4524 		*p1++ = '\0';
4525 	} else {
4526 		return;
4527 	}
4528 	if (*p == '2') {
4529 		asy->asy_cflag |= CSTOPB;
4530 		asy->asy_lcr |= STB;
4531 	}
4532 
4533 	/* ---- handshake is next ---- */
4534 	p = p1;
4535 	if (p) {
4536 		if ((p1 = strchr(p, ',')) != 0)
4537 			*p1++ = '\0';
4538 
4539 		if (*p == 'h')
4540 			asy->asy_cflag |= CRTSCTS;
4541 		else if (*p == 's')
4542 			asy->asy_cflag |= CRTSXOFF;
4543 	}
4544 }
4545 
4546 /*
4547  * Check for abort character sequence
4548  */
4549 static boolean_t
4550 abort_charseq_recognize(uchar_t ch)
4551 {
4552 	static int state = 0;
4553 #define	CNTRL(c) ((c)&037)
4554 	static char sequence[] = { '\r', '~', CNTRL('b') };
4555 
4556 	if (ch == sequence[state]) {
4557 		if (++state >= sizeof (sequence)) {
4558 			state = 0;
4559 			return (B_TRUE);
4560 		}
4561 	} else {
4562 		state = (ch == sequence[0]) ? 1 : 0;
4563 	}
4564 	return (B_FALSE);
4565 }
4566 
4567 /*
4568  * Flow control functions
4569  */
4570 /*
4571  * Software input flow control
4572  * This function can execute software input flow control sucessfully
4573  * at most of situations except that the line is in BREAK status
4574  * (timed and untimed break).
4575  * INPUT VALUE of onoff:
4576  *               FLOW_START means to send out a XON char
4577  *                          and clear SW input flow control flag.
4578  *               FLOW_STOP means to send out a XOFF char
4579  *                          and set SW input flow control flag.
4580  *               FLOW_CHECK means to check whether there is pending XON/XOFF
4581  *                          if it is true, send it out.
4582  * INPUT VALUE of type:
4583  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4584  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4585  *		 IN_FLOW_USER means flow control is due to user's commands
4586  * RETURN VALUE: B_FALSE means no flow control char is sent
4587  *               B_TRUE means one flow control char is sent
4588  */
4589 static boolean_t
4590 async_flowcontrol_sw_input(struct asycom *asy, async_flowc_action onoff,
4591     int type)
4592 {
4593 	struct asyncline *async = asy->asy_priv;
4594 	int instance = UNIT(async->async_dev);
4595 	int rval = B_FALSE;
4596 
4597 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4598 
4599 	if (!(async->async_ttycommon.t_iflag & IXOFF))
4600 		return (rval);
4601 
4602 	/*
4603 	 * If we get this far, then we know IXOFF is set.
4604 	 */
4605 	switch (onoff) {
4606 	case FLOW_STOP:
4607 		async->async_inflow_source |= type;
4608 
4609 		/*
4610 		 * We'll send an XOFF character for each of up to
4611 		 * three different input flow control attempts to stop input.
4612 		 * If we already send out one XOFF, but FLOW_STOP comes again,
4613 		 * it seems that input flow control becomes more serious,
4614 		 * then send XOFF again.
4615 		 */
4616 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4617 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4618 			async->async_flags |= ASYNC_SW_IN_FLOW |
4619 			    ASYNC_SW_IN_NEEDED;
4620 		DEBUGCONT2(ASY_DEBUG_SFLOW, "async%d: input sflow stop, "
4621 		    "type = %x\n", instance, async->async_inflow_source);
4622 		break;
4623 	case FLOW_START:
4624 		async->async_inflow_source &= ~type;
4625 		if (async->async_inflow_source == 0) {
4626 			async->async_flags = (async->async_flags &
4627 			    ~ASYNC_SW_IN_FLOW) | ASYNC_SW_IN_NEEDED;
4628 			DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: "
4629 			    "input sflow start\n", instance);
4630 		}
4631 		break;
4632 	default:
4633 		break;
4634 	}
4635 
4636 	if (((async->async_flags & (ASYNC_SW_IN_NEEDED | ASYNC_BREAK |
4637 	    ASYNC_OUT_SUSPEND)) == ASYNC_SW_IN_NEEDED) &&
4638 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE)) {
4639 		/*
4640 		 * If we get this far, then we know we need to send out
4641 		 * XON or XOFF char.
4642 		 */
4643 		async->async_flags = (async->async_flags &
4644 		    ~ASYNC_SW_IN_NEEDED) | ASYNC_BUSY;
4645 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
4646 		    async->async_flags & ASYNC_SW_IN_FLOW ?
4647 		    async->async_stopc : async->async_startc);
4648 		rval = B_TRUE;
4649 	}
4650 	return (rval);
4651 }
4652 
4653 /*
4654  * Software output flow control
4655  * This function can be executed sucessfully at any situation.
4656  * It does not handle HW, and just change the SW output flow control flag.
4657  * INPUT VALUE of onoff:
4658  *                 FLOW_START means to clear SW output flow control flag,
4659  *			also combine with HW output flow control status to
4660  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4661  *                 FLOW_STOP means to set SW output flow control flag,
4662  *			also clear ASYNC_OUT_FLW_RESUME.
4663  */
4664 static void
4665 async_flowcontrol_sw_output(struct asycom *asy, async_flowc_action onoff)
4666 {
4667 	struct asyncline *async = asy->asy_priv;
4668 	int instance = UNIT(async->async_dev);
4669 
4670 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4671 
4672 	if (!(async->async_ttycommon.t_iflag & IXON))
4673 		return;
4674 
4675 	switch (onoff) {
4676 	case FLOW_STOP:
4677 		async->async_flags |= ASYNC_SW_OUT_FLW;
4678 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4679 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow stop\n",
4680 		    instance);
4681 		break;
4682 	case FLOW_START:
4683 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
4684 		if (!(async->async_flags & ASYNC_HW_OUT_FLW))
4685 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4686 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow start\n",
4687 		    instance);
4688 		break;
4689 	default:
4690 		break;
4691 	}
4692 }
4693 
4694 /*
4695  * Hardware input flow control
4696  * This function can be executed sucessfully at any situation.
4697  * It directly changes RTS depending on input parameter onoff.
4698  * INPUT VALUE of onoff:
4699  *       FLOW_START means to clear HW input flow control flag,
4700  *                  and pull up RTS if it is low.
4701  *       FLOW_STOP means to set HW input flow control flag,
4702  *                  and low RTS if it is high.
4703  * INPUT VALUE of type:
4704  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4705  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4706  *		 IN_FLOW_USER means flow control is due to user's commands
4707  */
4708 static void
4709 async_flowcontrol_hw_input(struct asycom *asy, async_flowc_action onoff,
4710     int type)
4711 {
4712 	uchar_t	mcr;
4713 	uchar_t	flag;
4714 	struct asyncline *async = asy->asy_priv;
4715 	int instance = UNIT(async->async_dev);
4716 
4717 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4718 
4719 	if (!(async->async_ttycommon.t_cflag & CRTSXOFF))
4720 		return;
4721 
4722 	switch (onoff) {
4723 	case FLOW_STOP:
4724 		async->async_inflow_source |= type;
4725 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4726 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4727 			async->async_flags |= ASYNC_HW_IN_FLOW;
4728 		DEBUGCONT2(ASY_DEBUG_HFLOW, "async%d: input hflow stop, "
4729 		    "type = %x\n", instance, async->async_inflow_source);
4730 		break;
4731 	case FLOW_START:
4732 		async->async_inflow_source &= ~type;
4733 		if (async->async_inflow_source == 0) {
4734 			async->async_flags &= ~ASYNC_HW_IN_FLOW;
4735 			DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: "
4736 			    "input hflow start\n", instance);
4737 		}
4738 		break;
4739 	default:
4740 		break;
4741 	}
4742 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4743 	flag = (async->async_flags & ASYNC_HW_IN_FLOW) ? 0 : RTS;
4744 
4745 	if (((mcr ^ flag) & RTS) != 0) {
4746 		ddi_put8(asy->asy_iohandle,
4747 		    asy->asy_ioaddr + MCR, (mcr ^ RTS));
4748 	}
4749 }
4750 
4751 /*
4752  * Hardware output flow control
4753  * This function can execute HW output flow control sucessfully
4754  * at any situation.
4755  * It doesn't really change RTS, and just change
4756  * HW output flow control flag depending on CTS status.
4757  * INPUT VALUE of onoff:
4758  *                FLOW_START means to clear HW output flow control flag.
4759  *			also combine with SW output flow control status to
4760  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4761  *                FLOW_STOP means to set HW output flow control flag.
4762  *			also clear ASYNC_OUT_FLW_RESUME.
4763  */
4764 static void
4765 async_flowcontrol_hw_output(struct asycom *asy, async_flowc_action onoff)
4766 {
4767 	struct asyncline *async = asy->asy_priv;
4768 	int instance = UNIT(async->async_dev);
4769 
4770 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4771 
4772 	if (!(async->async_ttycommon.t_cflag & CRTSCTS))
4773 		return;
4774 
4775 	switch (onoff) {
4776 	case FLOW_STOP:
4777 		async->async_flags |= ASYNC_HW_OUT_FLW;
4778 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4779 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow stop\n",
4780 		    instance);
4781 		break;
4782 	case FLOW_START:
4783 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
4784 		if (!(async->async_flags & ASYNC_SW_OUT_FLW))
4785 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4786 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow start\n",
4787 		    instance);
4788 		break;
4789 	default:
4790 		break;
4791 	}
4792 }
4793 
4794 
4795 /*
4796  * quiesce(9E) entry point.
4797  *
4798  * This function is called when the system is single-threaded at high
4799  * PIL with preemption disabled. Therefore, this function must not be
4800  * blocked.
4801  *
4802  * This function returns DDI_SUCCESS on success, or DDI_FAILURE on failure.
4803  * DDI_FAILURE indicates an error condition and should almost never happen.
4804  */
4805 static int
4806 asyquiesce(dev_info_t *devi)
4807 {
4808 	int instance;
4809 	struct asycom *asy;
4810 
4811 	instance = ddi_get_instance(devi);	/* find out which unit */
4812 
4813 	asy = ddi_get_soft_state(asy_soft_state, instance);
4814 	if (asy == NULL)
4815 		return (DDI_FAILURE);
4816 
4817 	/* disable all interrupts */
4818 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
4819 
4820 	/* reset the FIFO */
4821 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
4822 
4823 	return (DDI_SUCCESS);
4824 }
4825