xref: /illumos-gate/usr/src/uts/common/io/asy.c (revision 3fced4392c3510db4e569c4f8188c45bb5b5f5d3)
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 		/* Process remaining RX characters and RX errors, if any */
686 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
687 		async_rxint(asy, lsr);
688 
689 		/* Wait for TX to drain */
690 		for (i = 1000; i > 0; i--) {
691 			lsr = ddi_get8(asy->asy_iohandle,
692 			    asy->asy_ioaddr + LSR);
693 			if ((lsr & (XSRE | XHRE)) == (XSRE | XHRE))
694 				break;
695 			delay(drv_usectohz(10000));
696 		}
697 		if (i == 0)
698 			cmn_err(CE_WARN,
699 			    "asy: transmitter wasn't drained before "
700 			    "driver was suspended");
701 
702 		mutex_exit(&asy->asy_excl_hi);
703 		mutex_exit(&asy->asy_excl);
704 		mutex_exit(&asy->asy_soft_sr);
705 		break;
706 	}
707 	default:
708 		return (DDI_FAILURE);
709 	}
710 
711 	return (DDI_SUCCESS);
712 }
713 
714 /*
715  * asyprobe
716  * We don't bother probing for the hardware, as since Solaris 2.6, device
717  * nodes are only created for auto-detected hardware or nodes explicitly
718  * created by the user, e.g. via the DCA. However, we should check the
719  * device node is at least vaguely usable, i.e. we have a block of 8 i/o
720  * ports. This prevents attempting to attach to bogus serial ports which
721  * some BIOSs still partially report when they are disabled in the BIOS.
722  */
723 static int
724 asyprobe(dev_info_t *devi)
725 {
726 	return ((asy_get_io_regnum(devi, NULL) < 0) ?
727 	    DDI_PROBE_FAILURE : DDI_PROBE_DONTCARE);
728 }
729 
730 static int
731 asyattach(dev_info_t *devi, ddi_attach_cmd_t cmd)
732 {
733 	int instance;
734 	int mcr;
735 	int ret;
736 	int regnum = 0;
737 	int i;
738 	struct asycom *asy;
739 	char name[ASY_MINOR_LEN];
740 	int status;
741 	static ddi_device_acc_attr_t ioattr = {
742 		DDI_DEVICE_ATTR_V0,
743 		DDI_NEVERSWAP_ACC,
744 		DDI_STRICTORDER_ACC,
745 	};
746 
747 	instance = ddi_get_instance(devi);	/* find out which unit */
748 
749 	switch (cmd) {
750 	case DDI_ATTACH:
751 		break;
752 	case DDI_RESUME:
753 	{
754 		struct asyncline *async;
755 
756 #ifdef	DEBUG
757 		if (asy_nosuspend)
758 			return (DDI_SUCCESS);
759 #endif
760 		asy = ddi_get_soft_state(asy_soft_state, instance);
761 		if (asy == NULL)
762 			return (DDI_FAILURE);
763 
764 		mutex_enter(&asy->asy_soft_sr);
765 		mutex_enter(&asy->asy_excl);
766 		mutex_enter(&asy->asy_excl_hi);
767 
768 		async = asy->asy_priv;
769 		/* Disable interrupts */
770 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
771 		if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
772 			mutex_exit(&asy->asy_excl_hi);
773 			mutex_exit(&asy->asy_excl);
774 			mutex_exit(&asy->asy_soft_sr);
775 			cmn_err(CE_WARN, "!Cannot identify UART chip at %p\n",
776 			    (void *)asy->asy_ioaddr);
777 			return (DDI_FAILURE);
778 		}
779 		asy->asy_flags &= ~ASY_DDI_SUSPENDED;
780 		if (async->async_flags & ASYNC_ISOPEN) {
781 			asy_program(asy, ASY_INIT);
782 			/* Kick off output */
783 			if (async->async_ocnt > 0) {
784 				async_resume(async);
785 			} else {
786 				mutex_exit(&asy->asy_excl_hi);
787 				if (async->async_xmitblk)
788 					freeb(async->async_xmitblk);
789 				async->async_xmitblk = NULL;
790 				async_start(async);
791 				mutex_enter(&asy->asy_excl_hi);
792 			}
793 			ASYSETSOFT(asy);
794 		}
795 		mutex_exit(&asy->asy_excl_hi);
796 		mutex_exit(&asy->asy_excl);
797 		mutex_exit(&asy->asy_soft_sr);
798 
799 		mutex_enter(&asy->asy_excl);
800 		if (async->async_flags & ASYNC_RESUME_BUFCALL) {
801 			async->async_wbufcid = bufcall(async->async_wbufcds,
802 			    BPRI_HI, (void (*)(void *)) async_reioctl,
803 			    (void *)(intptr_t)async->async_common->asy_unit);
804 			async->async_flags &= ~ASYNC_RESUME_BUFCALL;
805 		}
806 		async_process_suspq(asy);
807 		mutex_exit(&asy->asy_excl);
808 		return (DDI_SUCCESS);
809 	}
810 	default:
811 		return (DDI_FAILURE);
812 	}
813 
814 	ret = ddi_soft_state_zalloc(asy_soft_state, instance);
815 	if (ret != DDI_SUCCESS)
816 		return (DDI_FAILURE);
817 	asy = ddi_get_soft_state(asy_soft_state, instance);
818 	ASSERT(asy != NULL);	/* can't fail - we only just allocated it */
819 	asy->asy_unit = instance;
820 	mutex_enter(&asy_glob_lock);
821 	if (instance > max_asy_instance)
822 		max_asy_instance = instance;
823 	mutex_exit(&asy_glob_lock);
824 
825 	regnum = asy_get_io_regnum(devi, asy);
826 
827 	if (regnum < 0 ||
828 	    ddi_regs_map_setup(devi, regnum, (caddr_t *)&asy->asy_ioaddr,
829 	    (offset_t)0, (offset_t)0, &ioattr, &asy->asy_iohandle)
830 	    != DDI_SUCCESS) {
831 		cmn_err(CE_WARN, "asy%d: could not map UART registers @ %p",
832 		    instance, (void *)asy->asy_ioaddr);
833 
834 		asy_soft_state_free(asy);
835 		return (DDI_FAILURE);
836 	}
837 
838 	DEBUGCONT2(ASY_DEBUG_INIT, "asy%dattach: UART @ %p\n",
839 	    instance, (void *)asy->asy_ioaddr);
840 
841 	mutex_enter(&asy_glob_lock);
842 	if (com_ports == NULL) {	/* need to initialize com_ports */
843 		if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, devi, 0,
844 		    "motherboard-serial-ports", &com_ports, &num_com_ports) !=
845 		    DDI_PROP_SUCCESS) {
846 			/* Use our built-in COM[1234] values */
847 			com_ports = (int *)standard_com_ports;
848 			num_com_ports = sizeof (standard_com_ports) /
849 			    sizeof (standard_com_ports[0]);
850 		}
851 		if (num_com_ports > 10) {
852 			/* We run out of single digits for device properties */
853 			num_com_ports = 10;
854 			cmn_err(CE_WARN,
855 			    "More than %d motherboard-serial-ports",
856 			    num_com_ports);
857 		}
858 	}
859 	mutex_exit(&asy_glob_lock);
860 
861 	/*
862 	 * Lookup the i/o address to see if this is a standard COM port
863 	 * in which case we assign it the correct tty[a-d] to match the
864 	 * COM port number, or some other i/o address in which case it
865 	 * will be assigned /dev/term/[0123...] in some rather arbitrary
866 	 * fashion.
867 	 */
868 
869 	for (i = 0; i < num_com_ports; i++) {
870 		if (asy->asy_ioaddr == (uint8_t *)(uintptr_t)com_ports[i]) {
871 			asy->asy_com_port = i + 1;
872 			break;
873 		}
874 	}
875 
876 	/*
877 	 * It appears that there was async hardware that on reset
878 	 * did not clear ICR.  Hence when we get to
879 	 * ddi_get_iblock_cookie below, this hardware would cause
880 	 * the system to hang if there was input available.
881 	 */
882 
883 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0x00);
884 
885 	/* establish default usage */
886 	asy->asy_mcr |= RTS|DTR;		/* do use RTS/DTR after open */
887 	asy->asy_lcr = STOP1|BITS8;		/* default to 1 stop 8 bits */
888 	asy->asy_bidx = B9600;			/* default to 9600  */
889 #ifdef DEBUG
890 	asy->asy_msint_cnt = 0;			/* # of times in async_msint */
891 #endif
892 	mcr = 0;				/* don't enable until open */
893 
894 	if (asy->asy_com_port != 0) {
895 		/*
896 		 * For motherboard ports, emulate tty eeprom properties.
897 		 * Actually, we can't tell if a port is motherboard or not,
898 		 * so for "motherboard ports", read standard DOS COM ports.
899 		 */
900 		switch (asy_getproperty(devi, asy, "ignore-cd")) {
901 		case 0:				/* *-ignore-cd=False */
902 			DEBUGCONT1(ASY_DEBUG_MODEM,
903 			    "asy%dattach: clear ASY_IGNORE_CD\n", instance);
904 			asy->asy_flags &= ~ASY_IGNORE_CD; /* wait for cd */
905 			break;
906 		case 1:				/* *-ignore-cd=True */
907 			/*FALLTHRU*/
908 		default:			/* *-ignore-cd not defined */
909 			/*
910 			 * We set rather silly defaults of soft carrier on
911 			 * and DTR/RTS raised here because it might be that
912 			 * one of the motherboard ports is the system console.
913 			 */
914 			DEBUGCONT1(ASY_DEBUG_MODEM,
915 			    "asy%dattach: set ASY_IGNORE_CD, set RTS & DTR\n",
916 			    instance);
917 			mcr = asy->asy_mcr;		/* rts/dtr on */
918 			asy->asy_flags |= ASY_IGNORE_CD;	/* ignore cd */
919 			break;
920 		}
921 
922 		/* Property for not raising DTR/RTS */
923 		switch (asy_getproperty(devi, asy, "rts-dtr-off")) {
924 		case 0:				/* *-rts-dtr-off=False */
925 			asy->asy_flags |= ASY_RTS_DTR_OFF;	/* OFF */
926 			mcr = asy->asy_mcr;		/* rts/dtr on */
927 			DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dattach: "
928 			    "ASY_RTS_DTR_OFF set and DTR & RTS set\n",
929 			    instance);
930 			break;
931 		case 1:				/* *-rts-dtr-off=True */
932 			/*FALLTHRU*/
933 		default:			/* *-rts-dtr-off undefined */
934 			break;
935 		}
936 
937 		/* Parse property for tty modes */
938 		asy_parse_mode(devi, asy);
939 	} else {
940 		DEBUGCONT1(ASY_DEBUG_MODEM,
941 		    "asy%dattach: clear ASY_IGNORE_CD, clear RTS & DTR\n",
942 		    instance);
943 		asy->asy_flags &= ~ASY_IGNORE_CD;	/* wait for cd */
944 	}
945 
946 	/*
947 	 * Initialize the port with default settings.
948 	 */
949 
950 	asy->asy_fifo_buf = 1;
951 	asy->asy_use_fifo = FIFO_OFF;
952 
953 	/*
954 	 * Get icookie for mutexes initialization
955 	 */
956 	if ((ddi_get_iblock_cookie(devi, 0, &asy->asy_iblock) !=
957 	    DDI_SUCCESS) ||
958 	    (ddi_get_soft_iblock_cookie(devi, DDI_SOFTINT_MED,
959 	    &asy->asy_soft_iblock) != DDI_SUCCESS)) {
960 		ddi_regs_map_free(&asy->asy_iohandle);
961 		cmn_err(CE_CONT,
962 		    "asy%d: could not hook interrupt for UART @ %p\n",
963 		    instance, (void *)asy->asy_ioaddr);
964 		asy_soft_state_free(asy);
965 		return (DDI_FAILURE);
966 	}
967 
968 	/*
969 	 * Initialize mutexes before accessing the hardware
970 	 */
971 	mutex_init(&asy->asy_soft_lock, NULL, MUTEX_DRIVER,
972 	    (void *)asy->asy_soft_iblock);
973 	mutex_init(&asy->asy_excl, NULL, MUTEX_DRIVER, NULL);
974 	mutex_init(&asy->asy_excl_hi, NULL, MUTEX_DRIVER,
975 	    (void *)asy->asy_iblock);
976 	mutex_init(&asy->asy_soft_sr, NULL, MUTEX_DRIVER,
977 	    (void *)asy->asy_soft_iblock);
978 	mutex_enter(&asy->asy_excl);
979 	mutex_enter(&asy->asy_excl_hi);
980 
981 	if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
982 		mutex_exit(&asy->asy_excl_hi);
983 		mutex_exit(&asy->asy_excl);
984 		mutex_destroy(&asy->asy_soft_lock);
985 		mutex_destroy(&asy->asy_excl);
986 		mutex_destroy(&asy->asy_excl_hi);
987 		mutex_destroy(&asy->asy_soft_sr);
988 		ddi_regs_map_free(&asy->asy_iohandle);
989 		cmn_err(CE_CONT, "!Cannot identify UART chip at %p\n",
990 		    (void *)asy->asy_ioaddr);
991 		asy_soft_state_free(asy);
992 		return (DDI_FAILURE);
993 	}
994 
995 	/* disable all interrupts */
996 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
997 	/* select baud rate generator */
998 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
999 	/* Set the baud rate to 9600 */
1000 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLL),
1001 	    asyspdtab[asy->asy_bidx] & 0xff);
1002 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLH),
1003 	    (asyspdtab[asy->asy_bidx] >> 8) & 0xff);
1004 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, asy->asy_lcr);
1005 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1006 
1007 	mutex_exit(&asy->asy_excl_hi);
1008 	mutex_exit(&asy->asy_excl);
1009 
1010 	/*
1011 	 * Set up the other components of the asycom structure for this port.
1012 	 */
1013 	asy->asy_dip = devi;
1014 
1015 	/*
1016 	 * Install per instance software interrupt handler.
1017 	 */
1018 	if (ddi_add_softintr(devi, DDI_SOFTINT_MED,
1019 	    &(asy->asy_softintr_id), NULL, 0, asysoftintr,
1020 	    (caddr_t)asy) != DDI_SUCCESS) {
1021 		mutex_destroy(&asy->asy_soft_lock);
1022 		mutex_destroy(&asy->asy_excl);
1023 		mutex_destroy(&asy->asy_excl_hi);
1024 		ddi_regs_map_free(&asy->asy_iohandle);
1025 		cmn_err(CE_CONT,
1026 		    "Can not set soft interrupt for ASY driver\n");
1027 		asy_soft_state_free(asy);
1028 		return (DDI_FAILURE);
1029 	}
1030 
1031 	mutex_enter(&asy->asy_excl);
1032 	mutex_enter(&asy->asy_excl_hi);
1033 
1034 	/*
1035 	 * Install interrupt handler for this device.
1036 	 */
1037 	if (ddi_add_intr(devi, 0, NULL, 0, asyintr,
1038 	    (caddr_t)asy) != DDI_SUCCESS) {
1039 		mutex_exit(&asy->asy_excl_hi);
1040 		mutex_exit(&asy->asy_excl);
1041 		ddi_remove_softintr(asy->asy_softintr_id);
1042 		mutex_destroy(&asy->asy_soft_lock);
1043 		mutex_destroy(&asy->asy_excl);
1044 		mutex_destroy(&asy->asy_excl_hi);
1045 		ddi_regs_map_free(&asy->asy_iohandle);
1046 		cmn_err(CE_CONT,
1047 		    "Can not set device interrupt for ASY driver\n");
1048 		asy_soft_state_free(asy);
1049 		return (DDI_FAILURE);
1050 	}
1051 
1052 	mutex_exit(&asy->asy_excl_hi);
1053 	mutex_exit(&asy->asy_excl);
1054 
1055 	asyinit(asy);	/* initialize the asyncline structure */
1056 
1057 	/* create minor device nodes for this device */
1058 	if (asy->asy_com_port != 0) {
1059 		/*
1060 		 * For DOS COM ports, add letter suffix so
1061 		 * devfsadm can create correct link names.
1062 		 */
1063 		name[0] = asy->asy_com_port + 'a' - 1;
1064 		name[1] = '\0';
1065 	} else {
1066 		/*
1067 		 * asy port which isn't a standard DOS COM
1068 		 * port gets a numeric name based on instance
1069 		 */
1070 		(void) snprintf(name, ASY_MINOR_LEN, "%d", instance);
1071 	}
1072 	status = ddi_create_minor_node(devi, name, S_IFCHR, instance,
1073 	    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB : DDI_NT_SERIAL, NULL);
1074 	if (status == DDI_SUCCESS) {
1075 		(void) strcat(name, ",cu");
1076 		status = ddi_create_minor_node(devi, name, S_IFCHR,
1077 		    OUTLINE | instance,
1078 		    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB_DO :
1079 		    DDI_NT_SERIAL_DO, NULL);
1080 	}
1081 
1082 	if (status != DDI_SUCCESS) {
1083 		struct asyncline *async = asy->asy_priv;
1084 
1085 		ddi_remove_minor_node(devi, NULL);
1086 		ddi_remove_intr(devi, 0, asy->asy_iblock);
1087 		ddi_remove_softintr(asy->asy_softintr_id);
1088 		mutex_destroy(&asy->asy_soft_lock);
1089 		mutex_destroy(&asy->asy_excl);
1090 		mutex_destroy(&asy->asy_excl_hi);
1091 		cv_destroy(&async->async_flags_cv);
1092 		ddi_regs_map_free(&asy->asy_iohandle);
1093 		asy_soft_state_free(asy);
1094 		return (DDI_FAILURE);
1095 	}
1096 
1097 	/*
1098 	 * Fill in the polled I/O structure.
1099 	 */
1100 	asy->polledio.cons_polledio_version = CONSPOLLEDIO_V0;
1101 	asy->polledio.cons_polledio_argument = (cons_polledio_arg_t)asy;
1102 	asy->polledio.cons_polledio_putchar = asyputchar;
1103 	asy->polledio.cons_polledio_getchar = asygetchar;
1104 	asy->polledio.cons_polledio_ischar = asyischar;
1105 	asy->polledio.cons_polledio_enter = NULL;
1106 	asy->polledio.cons_polledio_exit = NULL;
1107 
1108 	ddi_report_dev(devi);
1109 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dattach: done\n", instance);
1110 	return (DDI_SUCCESS);
1111 }
1112 
1113 /*ARGSUSED*/
1114 static int
1115 asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
1116 	void **result)
1117 {
1118 	dev_t dev = (dev_t)arg;
1119 	int instance, error;
1120 	struct asycom *asy;
1121 
1122 	instance = UNIT(dev);
1123 
1124 	switch (infocmd) {
1125 	case DDI_INFO_DEVT2DEVINFO:
1126 		asy = ddi_get_soft_state(asy_soft_state, instance);
1127 		if ((asy == NULL) || (asy->asy_dip == NULL))
1128 			error = DDI_FAILURE;
1129 		else {
1130 			*result = (void *) asy->asy_dip;
1131 			error = DDI_SUCCESS;
1132 		}
1133 		break;
1134 	case DDI_INFO_DEVT2INSTANCE:
1135 		*result = (void *)(intptr_t)instance;
1136 		error = DDI_SUCCESS;
1137 		break;
1138 	default:
1139 		error = DDI_FAILURE;
1140 	}
1141 	return (error);
1142 }
1143 
1144 /* asy_getproperty -- walk through all name variants until we find a match */
1145 
1146 static int
1147 asy_getproperty(dev_info_t *devi, struct asycom *asy, const char *property)
1148 {
1149 	int len;
1150 	int ret;
1151 	char letter = asy->asy_com_port + 'a' - 1;	/* for ttya */
1152 	char number = asy->asy_com_port + '0';		/* for COM1 */
1153 	char val[40];
1154 	char name[40];
1155 
1156 	/* Property for ignoring DCD */
1157 	(void) sprintf(name, "tty%c-%s", letter, property);
1158 	len = sizeof (val);
1159 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1160 	if (ret != DDI_PROP_SUCCESS) {
1161 		(void) sprintf(name, "com%c-%s", number, property);
1162 		len = sizeof (val);
1163 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1164 	}
1165 	if (ret != DDI_PROP_SUCCESS) {
1166 		(void) sprintf(name, "tty0%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, "port-%c-%s", letter, property);
1172 		len = sizeof (val);
1173 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1174 	}
1175 	if (ret != DDI_PROP_SUCCESS)
1176 		return (-1);		/* property non-existant */
1177 	if (val[0] == 'f' || val[0] == 'F' || val[0] == '0')
1178 		return (0);		/* property false/0 */
1179 	return (1);			/* property true/!0 */
1180 }
1181 
1182 /* asy_soft_state_free - local wrapper for ddi_soft_state_free(9F) */
1183 
1184 static void
1185 asy_soft_state_free(struct asycom *asy)
1186 {
1187 	mutex_enter(&asy_glob_lock);
1188 	/* If we were the max_asy_instance, work out new value */
1189 	if (asy->asy_unit == max_asy_instance) {
1190 		while (--max_asy_instance >= 0) {
1191 			if (ddi_get_soft_state(asy_soft_state,
1192 			    max_asy_instance) != NULL)
1193 				break;
1194 		}
1195 	}
1196 	mutex_exit(&asy_glob_lock);
1197 
1198 	if (asy->asy_priv != NULL) {
1199 		kmem_free(asy->asy_priv, sizeof (struct asyncline));
1200 		asy->asy_priv = NULL;
1201 	}
1202 	ddi_soft_state_free(asy_soft_state, asy->asy_unit);
1203 }
1204 
1205 static char *
1206 asy_hw_name(struct asycom *asy)
1207 {
1208 	switch (asy->asy_hwtype) {
1209 	case ASY8250A:
1210 		return ("8250A/16450");
1211 	case ASY16550:
1212 		return ("16550");
1213 	case ASY16550A:
1214 		return ("16550A");
1215 	case ASY16650:
1216 		return ("16650");
1217 	case ASY16750:
1218 		return ("16750");
1219 	default:
1220 		DEBUGNOTE2(ASY_DEBUG_INIT,
1221 		    "asy%d: asy_hw_name: unknown asy_hwtype: %d",
1222 		    asy->asy_unit, asy->asy_hwtype);
1223 		return ("?");
1224 	}
1225 }
1226 
1227 static int
1228 asy_identify_chip(dev_info_t *devi, struct asycom *asy)
1229 {
1230 	int ret;
1231 	int mcr;
1232 	dev_t dev;
1233 	uint_t hwtype;
1234 
1235 	if (asy_scr_test) {
1236 		/* Check scratch register works. */
1237 
1238 		/* write to scratch register */
1239 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, SCRTEST);
1240 		/* make sure that pattern doesn't just linger on the bus */
1241 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR, 0x00);
1242 		/* read data back from scratch register */
1243 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1244 		if (ret != SCRTEST) {
1245 			/*
1246 			 * Scratch register not working.
1247 			 * Probably not an async chip.
1248 			 * 8250 and 8250B don't have scratch registers,
1249 			 * but only worked in ancient PC XT's anyway.
1250 			 */
1251 			cmn_err(CE_CONT, "!asy%d: UART @ %p "
1252 			    "scratch register: expected 0x5a, got 0x%02x\n",
1253 			    asy->asy_unit, (void *)asy->asy_ioaddr, ret);
1254 			return (DDI_FAILURE);
1255 		}
1256 	}
1257 	/*
1258 	 * Use 16550 fifo reset sequence specified in NS application
1259 	 * note. Disable fifos until chip is initialized.
1260 	 */
1261 	ddi_put8(asy->asy_iohandle,
1262 	    asy->asy_ioaddr + FIFOR, 0x00);	/* clear */
1263 	ddi_put8(asy->asy_iohandle,
1264 	    asy->asy_ioaddr + FIFOR, FIFO_ON);	/* enable */
1265 	ddi_put8(asy->asy_iohandle,
1266 	    asy->asy_ioaddr + FIFOR, FIFO_ON | FIFORXFLSH);
1267 						/* reset */
1268 	if (asymaxchip >= ASY16650 && asy_scr_test) {
1269 		/*
1270 		 * Reset 16650 enhanced regs also, in case we have one of these
1271 		 */
1272 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1273 		    EFRACCESS);
1274 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1275 		    0);
1276 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1277 		    STOP1|BITS8);
1278 	}
1279 
1280 	/*
1281 	 * See what sort of FIFO we have.
1282 	 * Try enabling it and see what chip makes of this.
1283 	 */
1284 
1285 	asy->asy_fifor = 0;
1286 	asy->asy_hwtype = asymaxchip; /* just for asy_reset_fifo() */
1287 	if (asymaxchip >= ASY16550A)
1288 		asy->asy_fifor |=
1289 		    FIFO_ON | FIFODMA | (asy_trig_level & 0xff);
1290 	if (asymaxchip >= ASY16650)
1291 		asy->asy_fifor |= FIFOEXTRA1 | FIFOEXTRA2;
1292 
1293 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1294 
1295 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1296 	ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
1297 	DEBUGCONT4(ASY_DEBUG_CHIP,
1298 	    "asy%d: probe fifo FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1299 	    asy->asy_unit, asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH,
1300 	    ret, mcr);
1301 	switch (ret & 0xf0) {
1302 	case 0x40:
1303 		hwtype = ASY16550; /* 16550 with broken FIFO */
1304 		asy->asy_fifor = 0;
1305 		break;
1306 	case 0xc0:
1307 		hwtype = ASY16550A;
1308 		asy->asy_fifo_buf = 16;
1309 		asy->asy_use_fifo = FIFO_ON;
1310 		asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1311 		break;
1312 	case 0xe0:
1313 		hwtype = ASY16650;
1314 		asy->asy_fifo_buf = 32;
1315 		asy->asy_use_fifo = FIFO_ON;
1316 		asy->asy_fifor &= ~(FIFOEXTRA1);
1317 		break;
1318 	case 0xf0:
1319 		/*
1320 		 * Note we get 0xff if chip didn't return us anything,
1321 		 * e.g. if there's no chip there.
1322 		 */
1323 		if (ret == 0xff) {
1324 			cmn_err(CE_CONT, "asy%d: UART @ %p "
1325 			    "interrupt register: got 0xff\n",
1326 			    asy->asy_unit, (void *)asy->asy_ioaddr);
1327 			return (DDI_FAILURE);
1328 		}
1329 		/*FALLTHRU*/
1330 	case 0xd0:
1331 		hwtype = ASY16750;
1332 		asy->asy_fifo_buf = 64;
1333 		asy->asy_use_fifo = FIFO_ON;
1334 		break;
1335 	default:
1336 		hwtype = ASY8250A; /* No FIFO */
1337 		asy->asy_fifor = 0;
1338 	}
1339 
1340 	if (hwtype > asymaxchip) {
1341 		cmn_err(CE_CONT, "asy%d: UART @ %p "
1342 		    "unexpected probe result: "
1343 		    "FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1344 		    asy->asy_unit, (void *)asy->asy_ioaddr,
1345 		    asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH, ret, mcr);
1346 		return (DDI_FAILURE);
1347 	}
1348 
1349 	/*
1350 	 * Now reset the FIFO operation appropriate for the chip type.
1351 	 * Note we must call asy_reset_fifo() before any possible
1352 	 * downgrade of the asy->asy_hwtype, or it may not disable
1353 	 * the more advanced features we specifically want downgraded.
1354 	 */
1355 	asy_reset_fifo(asy, 0);
1356 	asy->asy_hwtype = hwtype;
1357 
1358 	/*
1359 	 * Check for Exar/Startech ST16C650, which will still look like a
1360 	 * 16550A until we enable its enhanced mode.
1361 	 */
1362 	if (asy->asy_hwtype == ASY16550A && asymaxchip >= ASY16650 &&
1363 	    asy_scr_test) {
1364 		/* Enable enhanced mode register access */
1365 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1366 		    EFRACCESS);
1367 		/* zero scratch register (not scratch register if enhanced) */
1368 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, 0);
1369 		/* Disable enhanced mode register access */
1370 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1371 		    STOP1|BITS8);
1372 		/* read back scratch register */
1373 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1374 		if (ret == SCRTEST) {
1375 			/* looks like we have an ST16650 -- enable it */
1376 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1377 			    EFRACCESS);
1378 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1379 			    ENHENABLE);
1380 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1381 			    STOP1|BITS8);
1382 			asy->asy_hwtype = ASY16650;
1383 			asy->asy_fifo_buf = 32;
1384 			asy->asy_fifor |= 0x10; /* 24 byte txfifo trigger */
1385 			asy_reset_fifo(asy, 0);
1386 		}
1387 	}
1388 
1389 	/*
1390 	 * If we think we might have a FIFO larger than 16 characters,
1391 	 * measure FIFO size and check it against expected.
1392 	 */
1393 	if (asy_fifo_test > 0 &&
1394 	    !(asy->asy_flags2 & ASY2_NO_LOOPBACK) &&
1395 	    (asy->asy_fifo_buf > 16 ||
1396 	    (asy_fifo_test > 1 && asy->asy_use_fifo == FIFO_ON) ||
1397 	    ASY_DEBUG(ASY_DEBUG_CHIP))) {
1398 		int i;
1399 
1400 		/* Set baud rate to 57600 (fairly arbitrary choice) */
1401 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1402 		    DLAB);
1403 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
1404 		    asyspdtab[B57600] & 0xff);
1405 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1406 		    (asyspdtab[B57600] >> 8) & 0xff);
1407 		/* Set 8 bits, 1 stop bit */
1408 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1409 		    STOP1|BITS8);
1410 		/* Set loopback mode */
1411 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1412 		    DTR | RTS | ASY_LOOP | OUT1 | OUT2);
1413 
1414 		/* Overfill fifo */
1415 		for (i = 0; i < asy->asy_fifo_buf * 2; i++) {
1416 			ddi_put8(asy->asy_iohandle,
1417 			    asy->asy_ioaddr + DAT, i);
1418 		}
1419 		/*
1420 		 * Now there's an interesting question here about which
1421 		 * FIFO we're testing the size of, RX or TX. We just
1422 		 * filled the TX FIFO much faster than it can empty,
1423 		 * although it is possible one or two characters may
1424 		 * have gone from it to the TX shift register.
1425 		 * We wait for enough time for all the characters to
1426 		 * move into the RX FIFO and any excess characters to
1427 		 * have been lost, and then read all the RX FIFO. So
1428 		 * the answer we finally get will be the size which is
1429 		 * the MIN(RX FIFO,(TX FIFO + 1 or 2)). The critical
1430 		 * one is actually the TX FIFO, because if we overfill
1431 		 * it in normal operation, the excess characters are
1432 		 * lost with no warning.
1433 		 */
1434 		/*
1435 		 * Wait for characters to move into RX FIFO.
1436 		 * In theory, 200 * asy->asy_fifo_buf * 2 should be
1437 		 * enough. However, in practice it isn't always, so we
1438 		 * increase to 400 so some slow 16550A's finish, and we
1439 		 * increase to 3 so we spot more characters coming back
1440 		 * than we sent, in case that should ever happen.
1441 		 */
1442 		delay(drv_usectohz(400 * asy->asy_fifo_buf * 3));
1443 
1444 		/* Now see how many characters we can read back */
1445 		for (i = 0; i < asy->asy_fifo_buf * 3; i++) {
1446 			ret = ddi_get8(asy->asy_iohandle,
1447 			    asy->asy_ioaddr + LSR);
1448 			if (!(ret & RCA))
1449 				break;	/* FIFO emptied */
1450 			(void) ddi_get8(asy->asy_iohandle,
1451 			    asy->asy_ioaddr + DAT); /* lose another */
1452 		}
1453 
1454 		DEBUGCONT3(ASY_DEBUG_CHIP,
1455 		    "asy%d FIFO size: expected=%d, measured=%d\n",
1456 		    asy->asy_unit, asy->asy_fifo_buf, i);
1457 
1458 		hwtype = asy->asy_hwtype;
1459 		if (i < asy->asy_fifo_buf) {
1460 			/*
1461 			 * FIFO is somewhat smaller than we anticipated.
1462 			 * If we have 16 characters usable, then this
1463 			 * UART will probably work well enough in
1464 			 * 16550A mode. If less than 16 characters,
1465 			 * then we'd better not use it at all.
1466 			 * UARTs with busted FIFOs do crop up.
1467 			 */
1468 			if (i >= 16 && asy->asy_fifo_buf >= 16) {
1469 				/* fall back to a 16550A */
1470 				hwtype = ASY16550A;
1471 				asy->asy_fifo_buf = 16;
1472 				asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1473 			} else {
1474 				/* fall back to no FIFO at all */
1475 				hwtype = ASY16550;
1476 				asy->asy_fifo_buf = 1;
1477 				asy->asy_use_fifo = FIFO_OFF;
1478 				asy->asy_fifor &=
1479 				    ~(FIFO_ON | FIFOEXTRA1 | FIFOEXTRA2);
1480 			}
1481 		}
1482 		/*
1483 		 * We will need to reprogram the FIFO if we changed
1484 		 * our mind about how to drive it above, and in any
1485 		 * case, it would be a good idea to flush any garbage
1486 		 * out incase the loopback test left anything behind.
1487 		 * Again as earlier above, we must call asy_reset_fifo()
1488 		 * before any possible downgrade of asy->asy_hwtype.
1489 		 */
1490 		if (asy->asy_hwtype >= ASY16650 && hwtype < ASY16650) {
1491 			/* Disable 16650 enhanced mode */
1492 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1493 			    EFRACCESS);
1494 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1495 			    0);
1496 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1497 			    STOP1|BITS8);
1498 		}
1499 		asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1500 		asy->asy_hwtype = hwtype;
1501 
1502 		/* Clear loopback mode and restore DTR/RTS */
1503 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1504 	}
1505 
1506 	DEBUGNOTE3(ASY_DEBUG_CHIP, "asy%d %s @ %p",
1507 	    asy->asy_unit, asy_hw_name(asy), (void *)asy->asy_ioaddr);
1508 
1509 	/* Make UART type visible in device tree for prtconf, etc */
1510 	dev = makedevice(DDI_MAJOR_T_UNKNOWN, asy->asy_unit);
1511 	(void) ddi_prop_update_string(dev, devi, "uart", asy_hw_name(asy));
1512 
1513 	if (asy->asy_hwtype == ASY16550)	/* for broken 16550's, */
1514 		asy->asy_hwtype = ASY8250A;	/* drive them as 8250A */
1515 
1516 	return (DDI_SUCCESS);
1517 }
1518 
1519 /*
1520  * asyinit() initializes the TTY protocol-private data for this channel
1521  * before enabling the interrupts.
1522  */
1523 static void
1524 asyinit(struct asycom *asy)
1525 {
1526 	struct asyncline *async;
1527 
1528 	asy->asy_priv = kmem_zalloc(sizeof (struct asyncline), KM_SLEEP);
1529 	async = asy->asy_priv;
1530 	mutex_enter(&asy->asy_excl);
1531 	async->async_common = asy;
1532 	cv_init(&async->async_flags_cv, NULL, CV_DRIVER, NULL);
1533 	mutex_exit(&asy->asy_excl);
1534 }
1535 
1536 /*ARGSUSED3*/
1537 static int
1538 asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr)
1539 {
1540 	struct asycom	*asy;
1541 	struct asyncline *async;
1542 	int		mcr;
1543 	int		unit;
1544 	int 		len;
1545 	struct termios 	*termiosp;
1546 
1547 	unit = UNIT(*dev);
1548 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dopen\n", unit);
1549 	asy = ddi_get_soft_state(asy_soft_state, unit);
1550 	if (asy == NULL)
1551 		return (ENXIO);		/* unit not configured */
1552 	async = asy->asy_priv;
1553 	mutex_enter(&asy->asy_excl);
1554 
1555 again:
1556 	mutex_enter(&asy->asy_excl_hi);
1557 
1558 	/*
1559 	 * Block waiting for carrier to come up, unless this is a no-delay open.
1560 	 */
1561 	if (!(async->async_flags & ASYNC_ISOPEN)) {
1562 		/*
1563 		 * Set the default termios settings (cflag).
1564 		 * Others are set in ldterm.
1565 		 */
1566 		mutex_exit(&asy->asy_excl_hi);
1567 
1568 		if (ddi_getlongprop(DDI_DEV_T_ANY, ddi_root_node(),
1569 		    0, "ttymodes",
1570 		    (caddr_t)&termiosp, &len) == DDI_PROP_SUCCESS &&
1571 		    len == sizeof (struct termios)) {
1572 			async->async_ttycommon.t_cflag = termiosp->c_cflag;
1573 			kmem_free(termiosp, len);
1574 		} else
1575 			cmn_err(CE_WARN,
1576 			    "asy: couldn't get ttymodes property!");
1577 		mutex_enter(&asy->asy_excl_hi);
1578 
1579 		/* eeprom mode support - respect properties */
1580 		if (asy->asy_cflag)
1581 			async->async_ttycommon.t_cflag = asy->asy_cflag;
1582 
1583 		async->async_ttycommon.t_iflag = 0;
1584 		async->async_ttycommon.t_iocpending = NULL;
1585 		async->async_ttycommon.t_size.ws_row = 0;
1586 		async->async_ttycommon.t_size.ws_col = 0;
1587 		async->async_ttycommon.t_size.ws_xpixel = 0;
1588 		async->async_ttycommon.t_size.ws_ypixel = 0;
1589 		async->async_dev = *dev;
1590 		async->async_wbufcid = 0;
1591 
1592 		async->async_startc = CSTART;
1593 		async->async_stopc = CSTOP;
1594 		asy_program(asy, ASY_INIT);
1595 	} else
1596 		if ((async->async_ttycommon.t_flags & TS_XCLUDE) &&
1597 		    secpolicy_excl_open(cr) != 0) {
1598 		mutex_exit(&asy->asy_excl_hi);
1599 		mutex_exit(&asy->asy_excl);
1600 		return (EBUSY);
1601 	} else if ((*dev & OUTLINE) && !(async->async_flags & ASYNC_OUT)) {
1602 		mutex_exit(&asy->asy_excl_hi);
1603 		mutex_exit(&asy->asy_excl);
1604 		return (EBUSY);
1605 	}
1606 
1607 	if (*dev & OUTLINE)
1608 		async->async_flags |= ASYNC_OUT;
1609 
1610 	/* Raise DTR on every open, but delay if it was just lowered. */
1611 	while (async->async_flags & ASYNC_DTR_DELAY) {
1612 		DEBUGCONT1(ASY_DEBUG_MODEM,
1613 		    "asy%dopen: waiting for the ASYNC_DTR_DELAY to be clear\n",
1614 		    unit);
1615 		mutex_exit(&asy->asy_excl_hi);
1616 		if (cv_wait_sig(&async->async_flags_cv,
1617 		    &asy->asy_excl) == 0) {
1618 			DEBUGCONT1(ASY_DEBUG_MODEM,
1619 			    "asy%dopen: interrupted by signal, exiting\n",
1620 			    unit);
1621 			mutex_exit(&asy->asy_excl);
1622 			return (EINTR);
1623 		}
1624 		mutex_enter(&asy->asy_excl_hi);
1625 	}
1626 
1627 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1628 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1629 	    mcr|(asy->asy_mcr&DTR));
1630 
1631 	DEBUGCONT3(ASY_DEBUG_INIT,
1632 	    "asy%dopen: \"Raise DTR on every open\": make mcr = %x, "
1633 	    "make TS_SOFTCAR = %s\n",
1634 	    unit, mcr|(asy->asy_mcr&DTR),
1635 	    (asy->asy_flags & ASY_IGNORE_CD) ? "ON" : "OFF");
1636 
1637 	if (asy->asy_flags & ASY_IGNORE_CD) {
1638 		DEBUGCONT1(ASY_DEBUG_MODEM,
1639 		    "asy%dopen: ASY_IGNORE_CD set, set TS_SOFTCAR\n",
1640 		    unit);
1641 		async->async_ttycommon.t_flags |= TS_SOFTCAR;
1642 	}
1643 	else
1644 		async->async_ttycommon.t_flags &= ~TS_SOFTCAR;
1645 
1646 	/*
1647 	 * Check carrier.
1648 	 */
1649 	asy->asy_msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
1650 	DEBUGCONT3(ASY_DEBUG_INIT, "asy%dopen: TS_SOFTCAR is %s, "
1651 	    "MSR & DCD is %s\n",
1652 	    unit,
1653 	    (async->async_ttycommon.t_flags & TS_SOFTCAR) ? "set" : "clear",
1654 	    (asy->asy_msr & DCD) ? "set" : "clear");
1655 
1656 	if (asy->asy_msr & DCD)
1657 		async->async_flags |= ASYNC_CARR_ON;
1658 	else
1659 		async->async_flags &= ~ASYNC_CARR_ON;
1660 	mutex_exit(&asy->asy_excl_hi);
1661 
1662 	/*
1663 	 * If FNDELAY and FNONBLOCK are clear, block until carrier up.
1664 	 * Quit on interrupt.
1665 	 */
1666 	if (!(flag & (FNDELAY|FNONBLOCK)) &&
1667 	    !(async->async_ttycommon.t_cflag & CLOCAL)) {
1668 		if ((!(async->async_flags & (ASYNC_CARR_ON|ASYNC_OUT)) &&
1669 		    !(async->async_ttycommon.t_flags & TS_SOFTCAR)) ||
1670 		    ((async->async_flags & ASYNC_OUT) &&
1671 		    !(*dev & OUTLINE))) {
1672 			async->async_flags |= ASYNC_WOPEN;
1673 			if (cv_wait_sig(&async->async_flags_cv,
1674 			    &asy->asy_excl) == B_FALSE) {
1675 				async->async_flags &= ~ASYNC_WOPEN;
1676 				mutex_exit(&asy->asy_excl);
1677 				return (EINTR);
1678 			}
1679 			async->async_flags &= ~ASYNC_WOPEN;
1680 			goto again;
1681 		}
1682 	} else if ((async->async_flags & ASYNC_OUT) && !(*dev & OUTLINE)) {
1683 		mutex_exit(&asy->asy_excl);
1684 		return (EBUSY);
1685 	}
1686 
1687 	async->async_ttycommon.t_readq = rq;
1688 	async->async_ttycommon.t_writeq = WR(rq);
1689 	rq->q_ptr = WR(rq)->q_ptr = (caddr_t)async;
1690 	mutex_exit(&asy->asy_excl);
1691 	/*
1692 	 * Caution here -- qprocson sets the pointers that are used by canput
1693 	 * called by async_softint.  ASYNC_ISOPEN must *not* be set until those
1694 	 * pointers are valid.
1695 	 */
1696 	qprocson(rq);
1697 	async->async_flags |= ASYNC_ISOPEN;
1698 	async->async_polltid = 0;
1699 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dopen: done\n", unit);
1700 	return (0);
1701 }
1702 
1703 static void
1704 async_progress_check(void *arg)
1705 {
1706 	struct asyncline *async = arg;
1707 	struct asycom	 *asy = async->async_common;
1708 	mblk_t *bp;
1709 
1710 	/*
1711 	 * We define "progress" as either waiting on a timed break or delay, or
1712 	 * having had at least one transmitter interrupt.  If none of these are
1713 	 * true, then just terminate the output and wake up that close thread.
1714 	 */
1715 	mutex_enter(&asy->asy_excl);
1716 	mutex_enter(&asy->asy_excl_hi);
1717 	if (!(async->async_flags & (ASYNC_BREAK|ASYNC_DELAY|ASYNC_PROGRESS))) {
1718 		async->async_ocnt = 0;
1719 		async->async_flags &= ~ASYNC_BUSY;
1720 		async->async_timer = 0;
1721 		bp = async->async_xmitblk;
1722 		async->async_xmitblk = NULL;
1723 		mutex_exit(&asy->asy_excl_hi);
1724 		if (bp != NULL)
1725 			freeb(bp);
1726 		/*
1727 		 * Since this timer is running, we know that we're in exit(2).
1728 		 * That means that the user can't possibly be waiting on any
1729 		 * valid ioctl(2) completion anymore, and we should just flush
1730 		 * everything.
1731 		 */
1732 		flushq(async->async_ttycommon.t_writeq, FLUSHALL);
1733 		cv_broadcast(&async->async_flags_cv);
1734 	} else {
1735 		async->async_flags &= ~ASYNC_PROGRESS;
1736 		async->async_timer = timeout(async_progress_check, async,
1737 		    drv_usectohz(asy_drain_check));
1738 		mutex_exit(&asy->asy_excl_hi);
1739 	}
1740 	mutex_exit(&asy->asy_excl);
1741 }
1742 
1743 /*
1744  * Release DTR so that asyopen() can raise it.
1745  */
1746 static void
1747 async_dtr_free(struct asyncline *async)
1748 {
1749 	struct asycom *asy = async->async_common;
1750 
1751 	DEBUGCONT0(ASY_DEBUG_MODEM,
1752 	    "async_dtr_free, clearing ASYNC_DTR_DELAY\n");
1753 	mutex_enter(&asy->asy_excl);
1754 	async->async_flags &= ~ASYNC_DTR_DELAY;
1755 	async->async_dtrtid = 0;
1756 	cv_broadcast(&async->async_flags_cv);
1757 	mutex_exit(&asy->asy_excl);
1758 }
1759 
1760 /*
1761  * Close routine.
1762  */
1763 /*ARGSUSED2*/
1764 static int
1765 asyclose(queue_t *q, int flag, cred_t *credp)
1766 {
1767 	struct asyncline *async;
1768 	struct asycom	 *asy;
1769 	int icr, lcr;
1770 #ifdef DEBUG
1771 	int instance;
1772 #endif
1773 
1774 	async = (struct asyncline *)q->q_ptr;
1775 	ASSERT(async != NULL);
1776 #ifdef DEBUG
1777 	instance = UNIT(async->async_dev);
1778 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose\n", instance);
1779 #endif
1780 	asy = async->async_common;
1781 
1782 	mutex_enter(&asy->asy_excl);
1783 	async->async_flags |= ASYNC_CLOSING;
1784 
1785 	/*
1786 	 * Turn off PPS handling early to avoid events occuring during
1787 	 * close.  Also reset the DCD edge monitoring bit.
1788 	 */
1789 	mutex_enter(&asy->asy_excl_hi);
1790 	asy->asy_flags &= ~(ASY_PPS | ASY_PPS_EDGE);
1791 	mutex_exit(&asy->asy_excl_hi);
1792 
1793 	/*
1794 	 * There are two flavors of break -- timed (M_BREAK or TCSBRK) and
1795 	 * untimed (TIOCSBRK).  For the timed case, these are enqueued on our
1796 	 * write queue and there's a timer running, so we don't have to worry
1797 	 * about them.  For the untimed case, though, the user obviously made a
1798 	 * mistake, because these are handled immediately.  We'll terminate the
1799 	 * break now and honor his implicit request by discarding the rest of
1800 	 * the data.
1801 	 */
1802 	if (async->async_flags & ASYNC_OUT_SUSPEND) {
1803 		if (async->async_utbrktid != 0) {
1804 			(void) untimeout(async->async_utbrktid);
1805 			async->async_utbrktid = 0;
1806 		}
1807 		mutex_enter(&asy->asy_excl_hi);
1808 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1809 		ddi_put8(asy->asy_iohandle,
1810 		    asy->asy_ioaddr + LCR, (lcr & ~SETBREAK));
1811 		mutex_exit(&asy->asy_excl_hi);
1812 		async->async_flags &= ~ASYNC_OUT_SUSPEND;
1813 		goto nodrain;
1814 	}
1815 
1816 	/*
1817 	 * If the user told us not to delay the close ("non-blocking"), then
1818 	 * don't bother trying to drain.
1819 	 *
1820 	 * If the user did M_STOP (ASYNC_STOPPED), there's no hope of ever
1821 	 * getting an M_START (since these messages aren't enqueued), and the
1822 	 * only other way to clear the stop condition is by loss of DCD, which
1823 	 * would discard the queue data.  Thus, we drop the output data if
1824 	 * ASYNC_STOPPED is set.
1825 	 */
1826 	if ((flag & (FNDELAY|FNONBLOCK)) ||
1827 	    (async->async_flags & ASYNC_STOPPED)) {
1828 		goto nodrain;
1829 	}
1830 
1831 	/*
1832 	 * If there's any pending output, then we have to try to drain it.
1833 	 * There are two main cases to be handled:
1834 	 *	- called by close(2): need to drain until done or until
1835 	 *	  a signal is received.  No timeout.
1836 	 *	- called by exit(2): need to drain while making progress
1837 	 *	  or until a timeout occurs.  No signals.
1838 	 *
1839 	 * If we can't rely on receiving a signal to get us out of a hung
1840 	 * session, then we have to use a timer.  In this case, we set a timer
1841 	 * to check for progress in sending the output data -- all that we ask
1842 	 * (at each interval) is that there's been some progress made.  Since
1843 	 * the interrupt routine grabs buffers from the write queue, we can't
1844 	 * trust changes in async_ocnt.  Instead, we use a progress flag.
1845 	 *
1846 	 * Note that loss of carrier will cause the output queue to be flushed,
1847 	 * and we'll wake up again and finish normally.
1848 	 */
1849 	if (!ddi_can_receive_sig() && asy_drain_check != 0) {
1850 		async->async_flags &= ~ASYNC_PROGRESS;
1851 		async->async_timer = timeout(async_progress_check, async,
1852 		    drv_usectohz(asy_drain_check));
1853 	}
1854 	while (async->async_ocnt > 0 ||
1855 	    async->async_ttycommon.t_writeq->q_first != NULL ||
1856 	    (async->async_flags & (ASYNC_BUSY|ASYNC_BREAK|ASYNC_DELAY))) {
1857 		if (cv_wait_sig(&async->async_flags_cv, &asy->asy_excl) == 0)
1858 			break;
1859 	}
1860 	if (async->async_timer != 0) {
1861 		(void) untimeout(async->async_timer);
1862 		async->async_timer = 0;
1863 	}
1864 
1865 nodrain:
1866 	async->async_ocnt = 0;
1867 	if (async->async_xmitblk != NULL)
1868 		freeb(async->async_xmitblk);
1869 	async->async_xmitblk = NULL;
1870 
1871 	/*
1872 	 * If line has HUPCL set or is incompletely opened fix up the modem
1873 	 * lines.
1874 	 */
1875 	DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dclose: next check HUPCL flag\n",
1876 	    instance);
1877 	mutex_enter(&asy->asy_excl_hi);
1878 	if ((async->async_ttycommon.t_cflag & HUPCL) ||
1879 	    (async->async_flags & ASYNC_WOPEN)) {
1880 		DEBUGCONT3(ASY_DEBUG_MODEM,
1881 		    "asy%dclose: HUPCL flag = %x, ASYNC_WOPEN flag = %x\n",
1882 		    instance,
1883 		    async->async_ttycommon.t_cflag & HUPCL,
1884 		    async->async_ttycommon.t_cflag & ASYNC_WOPEN);
1885 		async->async_flags |= ASYNC_DTR_DELAY;
1886 
1887 		/* turn off DTR, RTS but NOT interrupt to 386 */
1888 		if (asy->asy_flags & (ASY_IGNORE_CD|ASY_RTS_DTR_OFF)) {
1889 			DEBUGCONT3(ASY_DEBUG_MODEM,
1890 			    "asy%dclose: ASY_IGNORE_CD flag = %x, "
1891 			    "ASY_RTS_DTR_OFF flag = %x\n",
1892 			    instance,
1893 			    asy->asy_flags & ASY_IGNORE_CD,
1894 			    asy->asy_flags & ASY_RTS_DTR_OFF);
1895 
1896 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1897 			    asy->asy_mcr|OUT2);
1898 		} else {
1899 			DEBUGCONT1(ASY_DEBUG_MODEM,
1900 			    "asy%dclose: Dropping DTR and RTS\n", instance);
1901 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1902 			    OUT2);
1903 		}
1904 		async->async_dtrtid =
1905 		    timeout((void (*)())async_dtr_free,
1906 		    (caddr_t)async, drv_usectohz(asy_min_dtr_low));
1907 	}
1908 	/*
1909 	 * If nobody's using it now, turn off receiver interrupts.
1910 	 */
1911 	if ((async->async_flags & (ASYNC_WOPEN|ASYNC_ISOPEN)) == 0) {
1912 		icr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ICR);
1913 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1914 		    (icr & ~RIEN));
1915 	}
1916 	mutex_exit(&asy->asy_excl_hi);
1917 out:
1918 	ttycommon_close(&async->async_ttycommon);
1919 
1920 	/*
1921 	 * Cancel outstanding "bufcall" request.
1922 	 */
1923 	if (async->async_wbufcid != 0) {
1924 		unbufcall(async->async_wbufcid);
1925 		async->async_wbufcid = 0;
1926 	}
1927 
1928 	/* Note that qprocsoff can't be done until after interrupts are off */
1929 	qprocsoff(q);
1930 	q->q_ptr = WR(q)->q_ptr = NULL;
1931 	async->async_ttycommon.t_readq = NULL;
1932 	async->async_ttycommon.t_writeq = NULL;
1933 
1934 	/*
1935 	 * Clear out device state, except persistant device property flags.
1936 	 */
1937 	async->async_flags &= (ASYNC_DTR_DELAY|ASY_RTS_DTR_OFF);
1938 	cv_broadcast(&async->async_flags_cv);
1939 	mutex_exit(&asy->asy_excl);
1940 
1941 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose: done\n", instance);
1942 	return (0);
1943 }
1944 
1945 static boolean_t
1946 asy_isbusy(struct asycom *asy)
1947 {
1948 	struct asyncline *async;
1949 
1950 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_isbusy\n");
1951 	async = asy->asy_priv;
1952 	ASSERT(mutex_owned(&asy->asy_excl));
1953 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1954 /*
1955  * XXXX this should be recoded
1956  */
1957 	return ((async->async_ocnt > 0) ||
1958 	    ((ddi_get8(asy->asy_iohandle,
1959 	    asy->asy_ioaddr + LSR) & (XSRE|XHRE)) == 0));
1960 }
1961 
1962 static void
1963 asy_waiteot(struct asycom *asy)
1964 {
1965 	/*
1966 	 * Wait for the current transmission block and the
1967 	 * current fifo data to transmit. Once this is done
1968 	 * we may go on.
1969 	 */
1970 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_waiteot\n");
1971 	ASSERT(mutex_owned(&asy->asy_excl));
1972 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1973 	while (asy_isbusy(asy)) {
1974 		mutex_exit(&asy->asy_excl_hi);
1975 		mutex_exit(&asy->asy_excl);
1976 		drv_usecwait(10000);		/* wait .01 */
1977 		mutex_enter(&asy->asy_excl);
1978 		mutex_enter(&asy->asy_excl_hi);
1979 	}
1980 }
1981 
1982 /* asy_reset_fifo -- flush fifos and [re]program fifo control register */
1983 static void
1984 asy_reset_fifo(struct asycom *asy, uchar_t flush)
1985 {
1986 	uchar_t lcr;
1987 
1988 	/* On a 16750, we have to set DLAB in order to set FIFOEXTRA. */
1989 
1990 	if (asy->asy_hwtype >= ASY16750) {
1991 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1992 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1993 		    lcr | DLAB);
1994 	}
1995 
1996 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR,
1997 	    asy->asy_fifor | flush);
1998 
1999 	/* Clear DLAB */
2000 
2001 	if (asy->asy_hwtype >= ASY16750) {
2002 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
2003 	}
2004 }
2005 
2006 /*
2007  * Program the ASY port. Most of the async operation is based on the values
2008  * of 'c_iflag' and 'c_cflag'.
2009  */
2010 
2011 #define	BAUDINDEX(cflg)	(((cflg) & CBAUDEXT) ? \
2012 			(((cflg) & CBAUD) + CBAUD + 1) : ((cflg) & CBAUD))
2013 
2014 static void
2015 asy_program(struct asycom *asy, int mode)
2016 {
2017 	struct asyncline *async;
2018 	int baudrate, c_flag;
2019 	int icr, lcr;
2020 	int flush_reg;
2021 	int ocflags;
2022 #ifdef DEBUG
2023 	int instance;
2024 #endif
2025 
2026 	ASSERT(mutex_owned(&asy->asy_excl));
2027 	ASSERT(mutex_owned(&asy->asy_excl_hi));
2028 
2029 	async = asy->asy_priv;
2030 #ifdef DEBUG
2031 	instance = UNIT(async->async_dev);
2032 	DEBUGCONT2(ASY_DEBUG_PROCS,
2033 	    "asy%d_program: mode = 0x%08X, enter\n", instance, mode);
2034 #endif
2035 
2036 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
2037 
2038 	async->async_ttycommon.t_cflag &= ~(CIBAUD);
2039 
2040 	if (baudrate > CBAUD) {
2041 		async->async_ttycommon.t_cflag |= CIBAUDEXT;
2042 		async->async_ttycommon.t_cflag |=
2043 		    (((baudrate - CBAUD - 1) << IBSHIFT) & CIBAUD);
2044 	} else {
2045 		async->async_ttycommon.t_cflag &= ~CIBAUDEXT;
2046 		async->async_ttycommon.t_cflag |=
2047 		    ((baudrate << IBSHIFT) & CIBAUD);
2048 	}
2049 
2050 	c_flag = async->async_ttycommon.t_cflag &
2051 	    (CLOCAL|CREAD|CSTOPB|CSIZE|PARENB|PARODD|CBAUD|CBAUDEXT);
2052 
2053 	/* disable interrupts */
2054 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
2055 
2056 	ocflags = asy->asy_ocflag;
2057 
2058 	/* flush/reset the status registers */
2059 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
2060 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2061 	asy->asy_msr = flush_reg = ddi_get8(asy->asy_iohandle,
2062 	    asy->asy_ioaddr + MSR);
2063 	/*
2064 	 * The device is programmed in the open sequence, if we
2065 	 * have to hardware handshake, then this is a good time
2066 	 * to check if the device can receive any data.
2067 	 */
2068 
2069 	if ((CRTSCTS & async->async_ttycommon.t_cflag) && !(flush_reg & CTS)) {
2070 		async_flowcontrol_hw_output(asy, FLOW_STOP);
2071 	} else {
2072 		/*
2073 		 * We can not use async_flowcontrol_hw_output(asy, FLOW_START)
2074 		 * here, because if CRTSCTS is clear, we need clear
2075 		 * ASYNC_HW_OUT_FLW bit.
2076 		 */
2077 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
2078 	}
2079 
2080 	/*
2081 	 * If IXON is not set, clear ASYNC_SW_OUT_FLW;
2082 	 * If IXON is set, no matter what IXON flag is before this
2083 	 * function call to asy_program,
2084 	 * we will use the old ASYNC_SW_OUT_FLW status.
2085 	 * Because of handling IXON in the driver, we also should re-calculate
2086 	 * the value of ASYNC_OUT_FLW_RESUME bit, but in fact,
2087 	 * the TCSET* commands which call asy_program
2088 	 * are put into the write queue, so there is no output needed to
2089 	 * be resumed at this point.
2090 	 */
2091 	if (!(IXON & async->async_ttycommon.t_iflag))
2092 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
2093 
2094 	/* manually flush receive buffer or fifo (workaround for buggy fifos) */
2095 	if (mode == ASY_INIT)
2096 		if (asy->asy_use_fifo == FIFO_ON) {
2097 			for (flush_reg = asy->asy_fifo_buf; flush_reg-- > 0; ) {
2098 				(void) ddi_get8(asy->asy_iohandle,
2099 				    asy->asy_ioaddr + DAT);
2100 			}
2101 		} else {
2102 			flush_reg = ddi_get8(asy->asy_iohandle,
2103 			    asy->asy_ioaddr + DAT);
2104 		}
2105 
2106 	if (ocflags != (c_flag & ~CLOCAL) || mode == ASY_INIT) {
2107 		/* Set line control */
2108 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
2109 		lcr &= ~(WLS0|WLS1|STB|PEN|EPS);
2110 
2111 		if (c_flag & CSTOPB)
2112 			lcr |= STB;	/* 2 stop bits */
2113 
2114 		if (c_flag & PARENB)
2115 			lcr |= PEN;
2116 
2117 		if ((c_flag & PARODD) == 0)
2118 			lcr |= EPS;
2119 
2120 		switch (c_flag & CSIZE) {
2121 		case CS5:
2122 			lcr |= BITS5;
2123 			break;
2124 		case CS6:
2125 			lcr |= BITS6;
2126 			break;
2127 		case CS7:
2128 			lcr |= BITS7;
2129 			break;
2130 		case CS8:
2131 			lcr |= BITS8;
2132 			break;
2133 		}
2134 
2135 		/* set the baud rate, unless it is "0" */
2136 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
2137 
2138 		if (baudrate != 0) {
2139 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
2140 			    asyspdtab[baudrate] & 0xff);
2141 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
2142 			    (asyspdtab[baudrate] >> 8) & 0xff);
2143 		}
2144 		/* set the line control modes */
2145 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
2146 
2147 		/*
2148 		 * If we have a FIFO buffer, enable/flush
2149 		 * at intialize time, flush if transitioning from
2150 		 * CREAD off to CREAD on.
2151 		 */
2152 		if ((ocflags & CREAD) == 0 && (c_flag & CREAD) ||
2153 		    mode == ASY_INIT)
2154 			if (asy->asy_use_fifo == FIFO_ON)
2155 				asy_reset_fifo(asy, FIFORXFLSH);
2156 
2157 		/* remember the new cflags */
2158 		asy->asy_ocflag = c_flag & ~CLOCAL;
2159 	}
2160 
2161 	if (baudrate == 0)
2162 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
2163 		    (asy->asy_mcr & RTS) | OUT2);
2164 	else
2165 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
2166 		    asy->asy_mcr | OUT2);
2167 
2168 	/*
2169 	 * Call the modem status interrupt handler to check for the carrier
2170 	 * in case CLOCAL was turned off after the carrier came on.
2171 	 * (Note: Modem status interrupt is not enabled if CLOCAL is ON.)
2172 	 */
2173 	async_msint(asy);
2174 
2175 	/* Set interrupt control */
2176 	DEBUGCONT3(ASY_DEBUG_MODM2,
2177 	    "asy%d_program: c_flag & CLOCAL = %x t_cflag & CRTSCTS = %x\n",
2178 	    instance, c_flag & CLOCAL,
2179 	    async->async_ttycommon.t_cflag & CRTSCTS);
2180 
2181 	if ((c_flag & CLOCAL) && !(async->async_ttycommon.t_cflag & CRTSCTS))
2182 		/*
2183 		 * direct-wired line ignores DCD, so we don't enable modem
2184 		 * status interrupts.
2185 		 */
2186 		icr = (TIEN | SIEN);
2187 	else
2188 		icr = (TIEN | SIEN | MIEN);
2189 
2190 	if (c_flag & CREAD)
2191 		icr |= RIEN;
2192 
2193 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, icr);
2194 	DEBUGCONT1(ASY_DEBUG_PROCS, "asy%d_program: done\n", instance);
2195 }
2196 
2197 static boolean_t
2198 asy_baudok(struct asycom *asy)
2199 {
2200 	struct asyncline *async = asy->asy_priv;
2201 	int baudrate;
2202 
2203 
2204 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
2205 
2206 	if (baudrate >= sizeof (asyspdtab)/sizeof (*asyspdtab))
2207 		return (0);
2208 
2209 	return (baudrate == 0 || asyspdtab[baudrate]);
2210 }
2211 
2212 /*
2213  * asyintr() is the High Level Interrupt Handler.
2214  *
2215  * There are four different interrupt types indexed by ISR register values:
2216  *		0: modem
2217  *		1: Tx holding register is empty, ready for next char
2218  *		2: Rx register now holds a char to be picked up
2219  *		3: error or break on line
2220  * This routine checks the Bit 0 (interrupt-not-pending) to determine if
2221  * the interrupt is from this port.
2222  */
2223 uint_t
2224 asyintr(caddr_t argasy)
2225 {
2226 	struct asycom		*asy = (struct asycom *)argasy;
2227 	struct asyncline	*async;
2228 	int			ret_status = DDI_INTR_UNCLAIMED;
2229 	uchar_t			interrupt_id, lsr;
2230 
2231 	interrupt_id = ddi_get8(asy->asy_iohandle,
2232 	    asy->asy_ioaddr + ISR) & 0x0F;
2233 	async = asy->asy_priv;
2234 
2235 	if ((async == NULL) ||
2236 	    !(async->async_flags & (ASYNC_ISOPEN|ASYNC_WOPEN))) {
2237 		if (interrupt_id & NOINTERRUPT)
2238 			return (DDI_INTR_UNCLAIMED);
2239 		else {
2240 			/*
2241 			 * reset the device by:
2242 			 *	reading line status
2243 			 *	reading any data from data status register
2244 			 *	reading modem status
2245 			 */
2246 			(void) ddi_get8(asy->asy_iohandle,
2247 			    asy->asy_ioaddr + LSR);
2248 			(void) ddi_get8(asy->asy_iohandle,
2249 			    asy->asy_ioaddr + DAT);
2250 			asy->asy_msr = ddi_get8(asy->asy_iohandle,
2251 			    asy->asy_ioaddr + MSR);
2252 			return (DDI_INTR_CLAIMED);
2253 		}
2254 	}
2255 
2256 	mutex_enter(&asy->asy_excl_hi);
2257 	/*
2258 	 * We will loop until the interrupt line is pulled low. asy
2259 	 * interrupt is edge triggered.
2260 	 */
2261 	/* CSTYLED */
2262 	for (;; interrupt_id =
2263 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR) & 0x0F)) {
2264 
2265 		if (interrupt_id & NOINTERRUPT)
2266 			break;
2267 		ret_status = DDI_INTR_CLAIMED;
2268 
2269 		DEBUGCONT1(ASY_DEBUG_INTR, "asyintr: interrupt_id = 0x%d\n",
2270 		    interrupt_id);
2271 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2272 		switch (interrupt_id) {
2273 		case RxRDY:
2274 		case RSTATUS:
2275 		case FFTMOUT:
2276 			/* receiver interrupt or receiver errors */
2277 			async_rxint(asy, lsr);
2278 			break;
2279 		case TxRDY:
2280 			/* transmit interrupt */
2281 			async_txint(asy);
2282 			continue;
2283 		case MSTATUS:
2284 			/* modem status interrupt */
2285 			async_msint(asy);
2286 			break;
2287 		}
2288 		if ((lsr & XHRE) && (async->async_flags & ASYNC_BUSY) &&
2289 		    (async->async_ocnt > 0))
2290 			async_txint(asy);
2291 	}
2292 	mutex_exit(&asy->asy_excl_hi);
2293 	return (ret_status);
2294 }
2295 
2296 /*
2297  * Transmitter interrupt service routine.
2298  * If there is more data to transmit in the current pseudo-DMA block,
2299  * send the next character if output is not stopped or draining.
2300  * Otherwise, queue up a soft interrupt.
2301  *
2302  * XXX -  Needs review for HW FIFOs.
2303  */
2304 static void
2305 async_txint(struct asycom *asy)
2306 {
2307 	struct asyncline *async = asy->asy_priv;
2308 	int		fifo_len;
2309 
2310 	/*
2311 	 * If ASYNC_BREAK or ASYNC_OUT_SUSPEND has been set, return to
2312 	 * asyintr()'s context to claim the interrupt without performing
2313 	 * any action. No character will be loaded into FIFO/THR until
2314 	 * timed or untimed break is removed
2315 	 */
2316 	if (async->async_flags & (ASYNC_BREAK|ASYNC_OUT_SUSPEND))
2317 		return;
2318 
2319 	fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
2320 	if (fifo_len > asy_max_tx_fifo)
2321 		fifo_len = asy_max_tx_fifo;
2322 
2323 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
2324 		fifo_len--;
2325 
2326 	if (async->async_ocnt > 0 && fifo_len > 0 &&
2327 	    !(async->async_flags &
2328 	    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_STOPPED))) {
2329 		while (fifo_len-- > 0 && async->async_ocnt-- > 0) {
2330 			ddi_put8(asy->asy_iohandle,
2331 			    asy->asy_ioaddr + DAT, *async->async_optr++);
2332 		}
2333 		async->async_flags |= ASYNC_PROGRESS;
2334 	}
2335 
2336 	if (fifo_len <= 0)
2337 		return;
2338 
2339 	ASYSETSOFT(asy);
2340 }
2341 
2342 /*
2343  * Interrupt on port: handle PPS event.  This function is only called
2344  * for a port on which PPS event handling has been enabled.
2345  */
2346 static void
2347 asy_ppsevent(struct asycom *asy, int msr)
2348 {
2349 	if (asy->asy_flags & ASY_PPS_EDGE) {
2350 		/* Have seen leading edge, now look for and record drop */
2351 		if ((msr & DCD) == 0)
2352 			asy->asy_flags &= ~ASY_PPS_EDGE;
2353 		/*
2354 		 * Waiting for leading edge, look for rise; stamp event and
2355 		 * calibrate kernel clock.
2356 		 */
2357 	} else if (msr & DCD) {
2358 			/*
2359 			 * This code captures a timestamp at the designated
2360 			 * transition of the PPS signal (DCD asserted).  The
2361 			 * code provides a pointer to the timestamp, as well
2362 			 * as the hardware counter value at the capture.
2363 			 *
2364 			 * Note: the kernel has nano based time values while
2365 			 * NTP requires micro based, an in-line fast algorithm
2366 			 * to convert nsec to usec is used here -- see hrt2ts()
2367 			 * in common/os/timers.c for a full description.
2368 			 */
2369 			struct timeval *tvp = &asy_ppsev.tv;
2370 			timestruc_t ts;
2371 			long nsec, usec;
2372 
2373 			asy->asy_flags |= ASY_PPS_EDGE;
2374 			LED_OFF;
2375 			gethrestime(&ts);
2376 			LED_ON;
2377 			nsec = ts.tv_nsec;
2378 			usec = nsec + (nsec >> 2);
2379 			usec = nsec + (usec >> 1);
2380 			usec = nsec + (usec >> 2);
2381 			usec = nsec + (usec >> 4);
2382 			usec = nsec - (usec >> 3);
2383 			usec = nsec + (usec >> 2);
2384 			usec = nsec + (usec >> 3);
2385 			usec = nsec + (usec >> 4);
2386 			usec = nsec + (usec >> 1);
2387 			usec = nsec + (usec >> 6);
2388 			tvp->tv_usec = usec >> 10;
2389 			tvp->tv_sec = ts.tv_sec;
2390 
2391 			++asy_ppsev.serial;
2392 
2393 			/*
2394 			 * Because the kernel keeps a high-resolution time,
2395 			 * pass the current highres timestamp in tvp and zero
2396 			 * in usec.
2397 			 */
2398 			ddi_hardpps(tvp, 0);
2399 	}
2400 }
2401 
2402 /*
2403  * Receiver interrupt: RxRDY interrupt, FIFO timeout interrupt or receive
2404  * error interrupt.
2405  * Try to put the character into the circular buffer for this line; if it
2406  * overflows, indicate a circular buffer overrun. If this port is always
2407  * to be serviced immediately, or the character is a STOP character, or
2408  * more than 15 characters have arrived, queue up a soft interrupt to
2409  * drain the circular buffer.
2410  * XXX - needs review for hw FIFOs support.
2411  */
2412 
2413 static void
2414 async_rxint(struct asycom *asy, uchar_t lsr)
2415 {
2416 	struct asyncline *async = asy->asy_priv;
2417 	uchar_t c;
2418 	uint_t s, needsoft = 0;
2419 	tty_common_t *tp;
2420 	int looplim = asy->asy_fifo_buf * 2;
2421 
2422 	tp = &async->async_ttycommon;
2423 	if (!(tp->t_cflag & CREAD)) {
2424 		while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2425 			(void) (ddi_get8(asy->asy_iohandle,
2426 			    asy->asy_ioaddr + DAT) & 0xff);
2427 			lsr = ddi_get8(asy->asy_iohandle,
2428 			    asy->asy_ioaddr + LSR);
2429 			if (looplim-- < 0)		/* limit loop */
2430 				break;
2431 		}
2432 		return; /* line is not open for read? */
2433 	}
2434 
2435 	while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2436 		c = 0;
2437 		s = 0;				/* reset error status */
2438 		if (lsr & RCA) {
2439 			c = ddi_get8(asy->asy_iohandle,
2440 			    asy->asy_ioaddr + DAT) & 0xff;
2441 
2442 			/*
2443 			 * We handle XON/XOFF char if IXON is set,
2444 			 * but if received char is _POSIX_VDISABLE,
2445 			 * we left it to the up level module.
2446 			 */
2447 			if (tp->t_iflag & IXON) {
2448 				if ((c == async->async_stopc) &&
2449 				    (c != _POSIX_VDISABLE)) {
2450 					async_flowcontrol_sw_output(asy,
2451 					    FLOW_STOP);
2452 					goto check_looplim;
2453 				} else if ((c == async->async_startc) &&
2454 				    (c != _POSIX_VDISABLE)) {
2455 					async_flowcontrol_sw_output(asy,
2456 					    FLOW_START);
2457 					needsoft = 1;
2458 					goto check_looplim;
2459 				}
2460 				if ((tp->t_iflag & IXANY) &&
2461 				    (async->async_flags & ASYNC_SW_OUT_FLW)) {
2462 					async_flowcontrol_sw_output(asy,
2463 					    FLOW_START);
2464 					needsoft = 1;
2465 				}
2466 			}
2467 		}
2468 
2469 		/*
2470 		 * Check for character break sequence
2471 		 */
2472 		if ((abort_enable == KIOCABORTALTERNATE) &&
2473 		    (asy->asy_flags & ASY_CONSOLE)) {
2474 			if (abort_charseq_recognize(c))
2475 				abort_sequence_enter((char *)NULL);
2476 		}
2477 
2478 		/* Handle framing errors */
2479 		if (lsr & (PARERR|FRMERR|BRKDET|OVRRUN)) {
2480 			if (lsr & PARERR) {
2481 				if (tp->t_iflag & INPCK) /* parity enabled */
2482 					s |= PERROR;
2483 			}
2484 
2485 			if (lsr & (FRMERR|BRKDET))
2486 				s |= FRERROR;
2487 			if (lsr & OVRRUN) {
2488 				async->async_hw_overrun = 1;
2489 				s |= OVERRUN;
2490 			}
2491 		}
2492 
2493 		if (s == 0)
2494 			if ((tp->t_iflag & PARMRK) &&
2495 			    !(tp->t_iflag & (IGNPAR|ISTRIP)) &&
2496 			    (c == 0377))
2497 				if (RING_POK(async, 2)) {
2498 					RING_PUT(async, 0377);
2499 					RING_PUT(async, c);
2500 				} else
2501 					async->async_sw_overrun = 1;
2502 			else
2503 				if (RING_POK(async, 1))
2504 					RING_PUT(async, c);
2505 				else
2506 					async->async_sw_overrun = 1;
2507 		else
2508 			if (s & FRERROR) /* Handle framing errors */
2509 				if (c == 0)
2510 					if ((asy->asy_flags & ASY_CONSOLE) &&
2511 					    (abort_enable !=
2512 					    KIOCABORTALTERNATE))
2513 						abort_sequence_enter((char *)0);
2514 					else
2515 						async->async_break++;
2516 				else
2517 					if (RING_POK(async, 1))
2518 						RING_MARK(async, c, s);
2519 					else
2520 						async->async_sw_overrun = 1;
2521 			else /* Parity errors are handled by ldterm */
2522 				if (RING_POK(async, 1))
2523 					RING_MARK(async, c, s);
2524 				else
2525 					async->async_sw_overrun = 1;
2526 check_looplim:
2527 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2528 		if (looplim-- < 0)		/* limit loop */
2529 			break;
2530 	}
2531 	if ((RING_CNT(async) > (RINGSIZE * 3)/4) &&
2532 	    !(async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2533 		async_flowcontrol_hw_input(asy, FLOW_STOP, IN_FLOW_RINGBUFF);
2534 		(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2535 		    IN_FLOW_RINGBUFF);
2536 	}
2537 
2538 	if ((async->async_flags & ASYNC_SERVICEIMM) || needsoft ||
2539 	    (RING_FRAC(async)) || (async->async_polltid == 0))
2540 		ASYSETSOFT(asy);	/* need a soft interrupt */
2541 }
2542 
2543 /*
2544  * Modem status interrupt.
2545  *
2546  * (Note: It is assumed that the MSR hasn't been read by asyintr().)
2547  */
2548 
2549 static void
2550 async_msint(struct asycom *asy)
2551 {
2552 	struct asyncline *async = asy->asy_priv;
2553 	int msr, t_cflag = async->async_ttycommon.t_cflag;
2554 #ifdef DEBUG
2555 	int instance = UNIT(async->async_dev);
2556 #endif
2557 
2558 async_msint_retry:
2559 	/* this resets the interrupt */
2560 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2561 	DEBUGCONT10(ASY_DEBUG_STATE,
2562 	    "async%d_msint call #%d:\n"
2563 	    "   transition: %3s %3s %3s %3s\n"
2564 	    "current state: %3s %3s %3s %3s\n",
2565 	    instance,
2566 	    ++(asy->asy_msint_cnt),
2567 	    (msr & DCTS) ? "DCTS" : "    ",
2568 	    (msr & DDSR) ? "DDSR" : "    ",
2569 	    (msr & DRI)  ? "DRI " : "    ",
2570 	    (msr & DDCD) ? "DDCD" : "    ",
2571 	    (msr & CTS)  ? "CTS " : "    ",
2572 	    (msr & DSR)  ? "DSR " : "    ",
2573 	    (msr & RI)   ? "RI  " : "    ",
2574 	    (msr & DCD)  ? "DCD " : "    ");
2575 
2576 	/* If CTS status is changed, do H/W output flow control */
2577 	if ((t_cflag & CRTSCTS) && (((asy->asy_msr ^ msr) & CTS) != 0))
2578 		async_flowcontrol_hw_output(asy,
2579 		    msr & CTS ? FLOW_START : FLOW_STOP);
2580 	/*
2581 	 * Reading MSR resets the interrupt, we save the
2582 	 * value of msr so that other functions could examine MSR by
2583 	 * looking at asy_msr.
2584 	 */
2585 	asy->asy_msr = (uchar_t)msr;
2586 
2587 	/* Handle PPS event */
2588 	if (asy->asy_flags & ASY_PPS)
2589 		asy_ppsevent(asy, msr);
2590 
2591 	async->async_ext++;
2592 	ASYSETSOFT(asy);
2593 	/*
2594 	 * We will make sure that the modem status presented to us
2595 	 * during the previous read has not changed. If the chip samples
2596 	 * the modem status on the falling edge of the interrupt line,
2597 	 * and uses this state as the base for detecting change of modem
2598 	 * status, we would miss a change of modem status event that occured
2599 	 * after we initiated a read MSR operation.
2600 	 */
2601 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2602 	if (STATES(msr) != STATES(asy->asy_msr))
2603 		goto	async_msint_retry;
2604 }
2605 
2606 /*
2607  * Handle a second-stage interrupt.
2608  */
2609 /*ARGSUSED*/
2610 uint_t
2611 asysoftintr(caddr_t intarg)
2612 {
2613 	struct asycom *asy = (struct asycom *)intarg;
2614 	struct asyncline *async;
2615 	int rv;
2616 	uint_t cc;
2617 
2618 	/*
2619 	 * Test and clear soft interrupt.
2620 	 */
2621 	mutex_enter(&asy->asy_soft_lock);
2622 	DEBUGCONT0(ASY_DEBUG_PROCS, "asysoftintr: enter\n");
2623 	rv = asy->asysoftpend;
2624 	if (rv != 0)
2625 		asy->asysoftpend = 0;
2626 	mutex_exit(&asy->asy_soft_lock);
2627 
2628 	if (rv) {
2629 		if (asy->asy_priv == NULL)
2630 			return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2631 		async = (struct asyncline *)asy->asy_priv;
2632 		mutex_enter(&asy->asy_excl_hi);
2633 		if (asy->asy_flags & ASY_NEEDSOFT) {
2634 			asy->asy_flags &= ~ASY_NEEDSOFT;
2635 			mutex_exit(&asy->asy_excl_hi);
2636 			async_softint(asy);
2637 			mutex_enter(&asy->asy_excl_hi);
2638 		}
2639 
2640 		/*
2641 		 * There are some instances where the softintr is not
2642 		 * scheduled and hence not called. It so happens that
2643 		 * causes the last few characters to be stuck in the
2644 		 * ringbuffer. Hence, call the handler once again so
2645 		 * the last few characters are cleared.
2646 		 */
2647 		cc = RING_CNT(async);
2648 		mutex_exit(&asy->asy_excl_hi);
2649 		if (cc > 0)
2650 			(void) async_softint(asy);
2651 	}
2652 	return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2653 }
2654 
2655 /*
2656  * Handle a software interrupt.
2657  */
2658 static void
2659 async_softint(struct asycom *asy)
2660 {
2661 	struct asyncline *async = asy->asy_priv;
2662 	uint_t	cc;
2663 	mblk_t	*bp;
2664 	queue_t	*q;
2665 	uchar_t	val;
2666 	uchar_t	c;
2667 	tty_common_t	*tp;
2668 	int nb;
2669 	int instance = UNIT(async->async_dev);
2670 
2671 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint\n", instance);
2672 	mutex_enter(&asy->asy_excl_hi);
2673 	if (asy->asy_flags & ASY_DOINGSOFT) {
2674 		asy->asy_flags |= ASY_DOINGSOFT_RETRY;
2675 		mutex_exit(&asy->asy_excl_hi);
2676 		return;
2677 	}
2678 	asy->asy_flags |= ASY_DOINGSOFT;
2679 begin:
2680 	asy->asy_flags &= ~ASY_DOINGSOFT_RETRY;
2681 	mutex_exit(&asy->asy_excl_hi);
2682 	mutex_enter(&asy->asy_excl);
2683 	tp = &async->async_ttycommon;
2684 	q = tp->t_readq;
2685 	if (async->async_flags & ASYNC_OUT_FLW_RESUME) {
2686 		if (async->async_ocnt > 0) {
2687 			mutex_enter(&asy->asy_excl_hi);
2688 			async_resume(async);
2689 			mutex_exit(&asy->asy_excl_hi);
2690 		} else {
2691 			if (async->async_xmitblk)
2692 				freeb(async->async_xmitblk);
2693 			async->async_xmitblk = NULL;
2694 			async_start(async);
2695 		}
2696 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
2697 	}
2698 	mutex_enter(&asy->asy_excl_hi);
2699 	if (async->async_ext) {
2700 		async->async_ext = 0;
2701 		/* check for carrier up */
2702 		DEBUGCONT3(ASY_DEBUG_MODM2,
2703 		    "async%d_softint: asy_msr & DCD = %x, "
2704 		    "tp->t_flags & TS_SOFTCAR = %x\n",
2705 		    instance, asy->asy_msr & DCD, tp->t_flags & TS_SOFTCAR);
2706 
2707 		if (asy->asy_msr & DCD) {
2708 			/* carrier present */
2709 			if ((async->async_flags & ASYNC_CARR_ON) == 0) {
2710 				DEBUGCONT1(ASY_DEBUG_MODM2,
2711 				    "async%d_softint: set ASYNC_CARR_ON\n",
2712 				    instance);
2713 				async->async_flags |= ASYNC_CARR_ON;
2714 				if (async->async_flags & ASYNC_ISOPEN) {
2715 					mutex_exit(&asy->asy_excl_hi);
2716 					mutex_exit(&asy->asy_excl);
2717 					(void) putctl(q, M_UNHANGUP);
2718 					mutex_enter(&asy->asy_excl);
2719 					mutex_enter(&asy->asy_excl_hi);
2720 				}
2721 				cv_broadcast(&async->async_flags_cv);
2722 			}
2723 		} else {
2724 			if ((async->async_flags & ASYNC_CARR_ON) &&
2725 			    !(tp->t_cflag & CLOCAL) &&
2726 			    !(tp->t_flags & TS_SOFTCAR)) {
2727 				int flushflag;
2728 
2729 				DEBUGCONT1(ASY_DEBUG_MODEM,
2730 				    "async%d_softint: carrier dropped, "
2731 				    "so drop DTR\n",
2732 				    instance);
2733 				/*
2734 				 * Carrier went away.
2735 				 * Drop DTR, abort any output in
2736 				 * progress, indicate that output is
2737 				 * not stopped, and send a hangup
2738 				 * notification upstream.
2739 				 */
2740 				val = ddi_get8(asy->asy_iohandle,
2741 				    asy->asy_ioaddr + MCR);
2742 				ddi_put8(asy->asy_iohandle,
2743 				    asy->asy_ioaddr + MCR, (val & ~DTR));
2744 
2745 				if (async->async_flags & ASYNC_BUSY) {
2746 					DEBUGCONT0(ASY_DEBUG_BUSY,
2747 					    "async_softint: "
2748 					    "Carrier dropped.  "
2749 					    "Clearing async_ocnt\n");
2750 					async->async_ocnt = 0;
2751 				}	/* if */
2752 
2753 				async->async_flags &= ~ASYNC_STOPPED;
2754 				if (async->async_flags & ASYNC_ISOPEN) {
2755 					mutex_exit(&asy->asy_excl_hi);
2756 					mutex_exit(&asy->asy_excl);
2757 					(void) putctl(q, M_HANGUP);
2758 					mutex_enter(&asy->asy_excl);
2759 					DEBUGCONT1(ASY_DEBUG_MODEM,
2760 					    "async%d_softint: "
2761 					    "putctl(q, M_HANGUP)\n",
2762 					    instance);
2763 					/*
2764 					 * Flush FIFO buffers
2765 					 * Any data left in there is invalid now
2766 					 */
2767 					if (asy->asy_use_fifo == FIFO_ON)
2768 						asy_reset_fifo(asy, FIFOTXFLSH);
2769 					/*
2770 					 * Flush our write queue if we have one.
2771 					 * If we're in the midst of close, then
2772 					 * flush everything. Don't leave stale
2773 					 * ioctls lying about.
2774 					 */
2775 					flushflag = (async->async_flags &
2776 					    ASYNC_CLOSING) ? FLUSHALL :
2777 					    FLUSHDATA;
2778 					flushq(tp->t_writeq, flushflag);
2779 
2780 					/* active msg */
2781 					bp = async->async_xmitblk;
2782 					if (bp != NULL) {
2783 						freeb(bp);
2784 						async->async_xmitblk = NULL;
2785 					}
2786 
2787 					mutex_enter(&asy->asy_excl_hi);
2788 					async->async_flags &= ~ASYNC_BUSY;
2789 					/*
2790 					 * This message warns of Carrier loss
2791 					 * with data left to transmit can hang
2792 					 * the system.
2793 					 */
2794 					DEBUGCONT0(ASY_DEBUG_MODEM,
2795 					    "async_softint: Flushing to "
2796 					    "prevent HUPCL hanging\n");
2797 				}	/* if (ASYNC_ISOPEN) */
2798 			}	/* if (ASYNC_CARR_ON && CLOCAL) */
2799 			async->async_flags &= ~ASYNC_CARR_ON;
2800 			cv_broadcast(&async->async_flags_cv);
2801 		}	/* else */
2802 	}	/* if (async->async_ext) */
2803 
2804 	mutex_exit(&asy->asy_excl_hi);
2805 
2806 	/*
2807 	 * If data has been added to the circular buffer, remove
2808 	 * it from the buffer, and send it up the stream if there's
2809 	 * somebody listening. Try to do it 16 bytes at a time. If we
2810 	 * have more than 16 bytes to move, move 16 byte chunks and
2811 	 * leave the rest for next time around (maybe it will grow).
2812 	 */
2813 	mutex_enter(&asy->asy_excl_hi);
2814 	if (!(async->async_flags & ASYNC_ISOPEN)) {
2815 		RING_INIT(async);
2816 		goto rv;
2817 	}
2818 	if ((cc = RING_CNT(async)) == 0)
2819 		goto rv;
2820 	mutex_exit(&asy->asy_excl_hi);
2821 
2822 	if (!canput(q)) {
2823 		mutex_enter(&asy->asy_excl_hi);
2824 		if (!(async->async_inflow_source & IN_FLOW_STREAMS)) {
2825 			async_flowcontrol_hw_input(asy, FLOW_STOP,
2826 			    IN_FLOW_STREAMS);
2827 			(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2828 			    IN_FLOW_STREAMS);
2829 		}
2830 		goto rv;
2831 	}
2832 	if (async->async_inflow_source & IN_FLOW_STREAMS) {
2833 		mutex_enter(&asy->asy_excl_hi);
2834 		async_flowcontrol_hw_input(asy, FLOW_START,
2835 		    IN_FLOW_STREAMS);
2836 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2837 		    IN_FLOW_STREAMS);
2838 		mutex_exit(&asy->asy_excl_hi);
2839 	}
2840 
2841 	DEBUGCONT2(ASY_DEBUG_INPUT, "async%d_softint: %d char(s) in queue.\n",
2842 	    instance, cc);
2843 
2844 	if (!(bp = allocb(cc, BPRI_MED))) {
2845 		mutex_exit(&asy->asy_excl);
2846 		ttycommon_qfull(&async->async_ttycommon, q);
2847 		mutex_enter(&asy->asy_excl);
2848 		mutex_enter(&asy->asy_excl_hi);
2849 		goto rv;
2850 	}
2851 	mutex_enter(&asy->asy_excl_hi);
2852 	do {
2853 		if (RING_ERR(async, S_ERRORS)) {
2854 			RING_UNMARK(async);
2855 			c = RING_GET(async);
2856 			break;
2857 		} else
2858 			*bp->b_wptr++ = RING_GET(async);
2859 	} while (--cc);
2860 	mutex_exit(&asy->asy_excl_hi);
2861 	mutex_exit(&asy->asy_excl);
2862 	if (bp->b_wptr > bp->b_rptr) {
2863 			if (!canput(q)) {
2864 				asyerror(CE_NOTE, "asy%d: local queue full",
2865 				    instance);
2866 				freemsg(bp);
2867 			} else
2868 				(void) putq(q, bp);
2869 	} else
2870 		freemsg(bp);
2871 	/*
2872 	 * If we have a parity error, then send
2873 	 * up an M_BREAK with the "bad"
2874 	 * character as an argument. Let ldterm
2875 	 * figure out what to do with the error.
2876 	 */
2877 	if (cc) {
2878 		(void) putctl1(q, M_BREAK, c);
2879 		ASYSETSOFT(async->async_common);	/* finish cc chars */
2880 	}
2881 	mutex_enter(&asy->asy_excl);
2882 	mutex_enter(&asy->asy_excl_hi);
2883 rv:
2884 	if ((RING_CNT(async) < (RINGSIZE/4)) &&
2885 	    (async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2886 		async_flowcontrol_hw_input(asy, FLOW_START, IN_FLOW_RINGBUFF);
2887 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2888 		    IN_FLOW_RINGBUFF);
2889 	}
2890 
2891 	/*
2892 	 * If a transmission has finished, indicate that it's finished,
2893 	 * and start that line up again.
2894 	 */
2895 	if (async->async_break > 0) {
2896 		nb = async->async_break;
2897 		async->async_break = 0;
2898 		if (async->async_flags & ASYNC_ISOPEN) {
2899 			mutex_exit(&asy->asy_excl_hi);
2900 			mutex_exit(&asy->asy_excl);
2901 			for (; nb > 0; nb--)
2902 				(void) putctl(q, M_BREAK);
2903 			mutex_enter(&asy->asy_excl);
2904 			mutex_enter(&asy->asy_excl_hi);
2905 		}
2906 	}
2907 	if (async->async_ocnt <= 0 && (async->async_flags & ASYNC_BUSY)) {
2908 		DEBUGCONT2(ASY_DEBUG_BUSY,
2909 		    "async%d_softint: Clearing ASYNC_BUSY.  async_ocnt=%d\n",
2910 		    instance,
2911 		    async->async_ocnt);
2912 		async->async_flags &= ~ASYNC_BUSY;
2913 		mutex_exit(&asy->asy_excl_hi);
2914 		if (async->async_xmitblk)
2915 			freeb(async->async_xmitblk);
2916 		async->async_xmitblk = NULL;
2917 		async_start(async);
2918 		/*
2919 		 * If the flag isn't set after doing the async_start above, we
2920 		 * may have finished all the queued output.  Signal any thread
2921 		 * stuck in close.
2922 		 */
2923 		if (!(async->async_flags & ASYNC_BUSY))
2924 			cv_broadcast(&async->async_flags_cv);
2925 		mutex_enter(&asy->asy_excl_hi);
2926 	}
2927 	/*
2928 	 * A note about these overrun bits: all they do is *tell* someone
2929 	 * about an error- They do not track multiple errors. In fact,
2930 	 * you could consider them latched register bits if you like.
2931 	 * We are only interested in printing the error message once for
2932 	 * any cluster of overrun errrors.
2933 	 */
2934 	if (async->async_hw_overrun) {
2935 		if (async->async_flags & ASYNC_ISOPEN) {
2936 			mutex_exit(&asy->asy_excl_hi);
2937 			mutex_exit(&asy->asy_excl);
2938 			asyerror(CE_NOTE, "asy%d: silo overflow", instance);
2939 			mutex_enter(&asy->asy_excl);
2940 			mutex_enter(&asy->asy_excl_hi);
2941 		}
2942 		async->async_hw_overrun = 0;
2943 	}
2944 	if (async->async_sw_overrun) {
2945 		if (async->async_flags & ASYNC_ISOPEN) {
2946 			mutex_exit(&asy->asy_excl_hi);
2947 			mutex_exit(&asy->asy_excl);
2948 			asyerror(CE_NOTE, "asy%d: ring buffer overflow",
2949 			    instance);
2950 			mutex_enter(&asy->asy_excl);
2951 			mutex_enter(&asy->asy_excl_hi);
2952 		}
2953 		async->async_sw_overrun = 0;
2954 	}
2955 	if (asy->asy_flags & ASY_DOINGSOFT_RETRY) {
2956 		mutex_exit(&asy->asy_excl_hi);
2957 		mutex_exit(&asy->asy_excl);
2958 		goto begin;
2959 	}
2960 	asy->asy_flags &= ~ASY_DOINGSOFT;
2961 	mutex_exit(&asy->asy_excl_hi);
2962 	mutex_exit(&asy->asy_excl);
2963 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint: done\n", instance);
2964 }
2965 
2966 /*
2967  * Restart output on a line after a delay or break timer expired.
2968  */
2969 static void
2970 async_restart(void *arg)
2971 {
2972 	struct asyncline *async = (struct asyncline *)arg;
2973 	struct asycom *asy = async->async_common;
2974 	uchar_t lcr;
2975 
2976 	/*
2977 	 * If break timer expired, turn off the break bit.
2978 	 */
2979 #ifdef DEBUG
2980 	int instance = UNIT(async->async_dev);
2981 
2982 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_restart\n", instance);
2983 #endif
2984 	mutex_enter(&asy->asy_excl);
2985 	/*
2986 	 * If ASYNC_OUT_SUSPEND is also set, we don't really
2987 	 * clean the HW break, TIOCCBRK is responsible for this.
2988 	 */
2989 	if ((async->async_flags & ASYNC_BREAK) &&
2990 	    !(async->async_flags & ASYNC_OUT_SUSPEND)) {
2991 		mutex_enter(&asy->asy_excl_hi);
2992 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
2993 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
2994 		    (lcr & ~SETBREAK));
2995 		mutex_exit(&asy->asy_excl_hi);
2996 	}
2997 	async->async_flags &= ~(ASYNC_DELAY|ASYNC_BREAK);
2998 	cv_broadcast(&async->async_flags_cv);
2999 	async_start(async);
3000 
3001 	mutex_exit(&asy->asy_excl);
3002 }
3003 
3004 static void
3005 async_start(struct asyncline *async)
3006 {
3007 	async_nstart(async, 0);
3008 }
3009 
3010 /*
3011  * Start output on a line, unless it's busy, frozen, or otherwise.
3012  */
3013 /*ARGSUSED*/
3014 static void
3015 async_nstart(struct asyncline *async, int mode)
3016 {
3017 	struct asycom *asy = async->async_common;
3018 	int cc;
3019 	queue_t *q;
3020 	mblk_t *bp;
3021 	uchar_t *xmit_addr;
3022 	uchar_t	val;
3023 	int	fifo_len = 1;
3024 	boolean_t didsome;
3025 	mblk_t *nbp;
3026 
3027 #ifdef DEBUG
3028 	int instance = UNIT(async->async_dev);
3029 
3030 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_nstart\n", instance);
3031 #endif
3032 	if (asy->asy_use_fifo == FIFO_ON) {
3033 		fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
3034 		if (fifo_len > asy_max_tx_fifo)
3035 			fifo_len = asy_max_tx_fifo;
3036 	}
3037 
3038 	ASSERT(mutex_owned(&asy->asy_excl));
3039 
3040 	/*
3041 	 * If the chip is busy (i.e., we're waiting for a break timeout
3042 	 * to expire, or for the current transmission to finish, or for
3043 	 * output to finish draining from chip), don't grab anything new.
3044 	 */
3045 	if (async->async_flags & (ASYNC_BREAK|ASYNC_BUSY)) {
3046 		DEBUGCONT2((mode? ASY_DEBUG_OUT : 0),
3047 		    "async%d_nstart: start %s.\n",
3048 		    instance,
3049 		    async->async_flags & ASYNC_BREAK ? "break" : "busy");
3050 		return;
3051 	}
3052 
3053 	/*
3054 	 * Check only pended sw input flow control.
3055 	 */
3056 	mutex_enter(&asy->asy_excl_hi);
3057 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
3058 		fifo_len--;
3059 	mutex_exit(&asy->asy_excl_hi);
3060 
3061 	/*
3062 	 * If we're waiting for a delay timeout to expire, don't grab
3063 	 * anything new.
3064 	 */
3065 	if (async->async_flags & ASYNC_DELAY) {
3066 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
3067 		    "async%d_nstart: start ASYNC_DELAY.\n", instance);
3068 		return;
3069 	}
3070 
3071 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
3072 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
3073 		    "async%d_nstart: start writeq is null.\n", instance);
3074 		return;	/* not attached to a stream */
3075 	}
3076 
3077 	for (;;) {
3078 		if ((bp = getq(q)) == NULL)
3079 			return;	/* no data to transmit */
3080 
3081 		/*
3082 		 * We have a message block to work on.
3083 		 * Check whether it's a break, a delay, or an ioctl (the latter
3084 		 * occurs if the ioctl in question was waiting for the output
3085 		 * to drain).  If it's one of those, process it immediately.
3086 		 */
3087 		switch (bp->b_datap->db_type) {
3088 
3089 		case M_BREAK:
3090 			/*
3091 			 * Set the break bit, and arrange for "async_restart"
3092 			 * to be called in 1/4 second; it will turn the
3093 			 * break bit off, and call "async_start" to grab
3094 			 * the next message.
3095 			 */
3096 			mutex_enter(&asy->asy_excl_hi);
3097 			val = ddi_get8(asy->asy_iohandle,
3098 			    asy->asy_ioaddr + LCR);
3099 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3100 			    (val | SETBREAK));
3101 			mutex_exit(&asy->asy_excl_hi);
3102 			async->async_flags |= ASYNC_BREAK;
3103 			(void) timeout(async_restart, (caddr_t)async,
3104 			    drv_usectohz(1000000)/4);
3105 			freemsg(bp);
3106 			return;	/* wait for this to finish */
3107 
3108 		case M_DELAY:
3109 			/*
3110 			 * Arrange for "async_restart" to be called when the
3111 			 * delay expires; it will turn ASYNC_DELAY off,
3112 			 * and call "async_start" to grab the next message.
3113 			 */
3114 			(void) timeout(async_restart, (caddr_t)async,
3115 			    (int)(*(unsigned char *)bp->b_rptr + 6));
3116 			async->async_flags |= ASYNC_DELAY;
3117 			freemsg(bp);
3118 			return;	/* wait for this to finish */
3119 
3120 		case M_IOCTL:
3121 			/*
3122 			 * This ioctl was waiting for the output ahead of
3123 			 * it to drain; obviously, it has.  Do it, and
3124 			 * then grab the next message after it.
3125 			 */
3126 			mutex_exit(&asy->asy_excl);
3127 			async_ioctl(async, q, bp);
3128 			mutex_enter(&asy->asy_excl);
3129 			continue;
3130 		}
3131 
3132 		while (bp != NULL && ((cc = MBLKL(bp)) == 0)) {
3133 			nbp = bp->b_cont;
3134 			freeb(bp);
3135 			bp = nbp;
3136 		}
3137 		if (bp != NULL)
3138 			break;
3139 	}
3140 
3141 	/*
3142 	 * We have data to transmit.  If output is stopped, put
3143 	 * it back and try again later.
3144 	 */
3145 	if (async->async_flags & (ASYNC_HW_OUT_FLW | ASYNC_SW_OUT_FLW |
3146 	    ASYNC_STOPPED | ASYNC_OUT_SUSPEND)) {
3147 		(void) putbq(q, bp);
3148 		return;
3149 	}
3150 
3151 	async->async_xmitblk = bp;
3152 	xmit_addr = bp->b_rptr;
3153 	bp = bp->b_cont;
3154 	if (bp != NULL)
3155 		(void) putbq(q, bp);	/* not done with this message yet */
3156 
3157 	/*
3158 	 * In 5-bit mode, the high order bits are used
3159 	 * to indicate character sizes less than five,
3160 	 * so we need to explicitly mask before transmitting
3161 	 */
3162 	if ((async->async_ttycommon.t_cflag & CSIZE) == CS5) {
3163 		unsigned char *p = xmit_addr;
3164 		int cnt = cc;
3165 
3166 		while (cnt--)
3167 			*p++ &= (unsigned char) 0x1f;
3168 	}
3169 
3170 	/*
3171 	 * Set up this block for pseudo-DMA.
3172 	 */
3173 	mutex_enter(&asy->asy_excl_hi);
3174 	/*
3175 	 * If the transmitter is ready, shove the first
3176 	 * character out.
3177 	 */
3178 	didsome = B_FALSE;
3179 	while (--fifo_len >= 0 && cc > 0) {
3180 		if (!(ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) &
3181 		    XHRE))
3182 			break;
3183 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
3184 		    *xmit_addr++);
3185 		cc--;
3186 		didsome = B_TRUE;
3187 	}
3188 	async->async_optr = xmit_addr;
3189 	async->async_ocnt = cc;
3190 	if (didsome)
3191 		async->async_flags |= ASYNC_PROGRESS;
3192 	DEBUGCONT2(ASY_DEBUG_BUSY,
3193 	    "async%d_nstart: Set ASYNC_BUSY.  async_ocnt=%d\n",
3194 	    instance, async->async_ocnt);
3195 	async->async_flags |= ASYNC_BUSY;
3196 	mutex_exit(&asy->asy_excl_hi);
3197 }
3198 
3199 /*
3200  * Resume output by poking the transmitter.
3201  */
3202 static void
3203 async_resume(struct asyncline *async)
3204 {
3205 	struct asycom *asy = async->async_common;
3206 #ifdef DEBUG
3207 	int instance;
3208 #endif
3209 
3210 	ASSERT(mutex_owned(&asy->asy_excl_hi));
3211 #ifdef DEBUG
3212 	instance = UNIT(async->async_dev);
3213 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_resume\n", instance);
3214 #endif
3215 
3216 	if (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE) {
3217 		if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
3218 			return;
3219 		if (async->async_ocnt > 0 &&
3220 		    !(async->async_flags &
3221 		    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_OUT_SUSPEND))) {
3222 			ddi_put8(asy->asy_iohandle,
3223 			    asy->asy_ioaddr + DAT, *async->async_optr++);
3224 			async->async_ocnt--;
3225 			async->async_flags |= ASYNC_PROGRESS;
3226 		}
3227 	}
3228 }
3229 
3230 /*
3231  * Hold the untimed break to last the minimum time.
3232  */
3233 static void
3234 async_hold_utbrk(void *arg)
3235 {
3236 	struct asyncline *async = arg;
3237 	struct asycom *asy = async->async_common;
3238 
3239 	mutex_enter(&asy->asy_excl);
3240 	async->async_flags &= ~ASYNC_HOLD_UTBRK;
3241 	cv_broadcast(&async->async_flags_cv);
3242 	async->async_utbrktid = 0;
3243 	mutex_exit(&asy->asy_excl);
3244 }
3245 
3246 /*
3247  * Resume the untimed break.
3248  */
3249 static void
3250 async_resume_utbrk(struct asyncline *async)
3251 {
3252 	uchar_t	val;
3253 	struct asycom *asy = async->async_common;
3254 	ASSERT(mutex_owned(&asy->asy_excl));
3255 
3256 	/*
3257 	 * Because the wait time is very short,
3258 	 * so we use uninterruptably wait.
3259 	 */
3260 	while (async->async_flags & ASYNC_HOLD_UTBRK) {
3261 		cv_wait(&async->async_flags_cv, &asy->asy_excl);
3262 	}
3263 	mutex_enter(&asy->asy_excl_hi);
3264 	/*
3265 	 * Timed break and untimed break can exist simultaneously,
3266 	 * if ASYNC_BREAK is also set at here, we don't
3267 	 * really clean the HW break.
3268 	 */
3269 	if (!(async->async_flags & ASYNC_BREAK)) {
3270 		val = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
3271 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3272 		    (val & ~SETBREAK));
3273 	}
3274 	async->async_flags &= ~ASYNC_OUT_SUSPEND;
3275 	cv_broadcast(&async->async_flags_cv);
3276 	if (async->async_ocnt > 0) {
3277 		async_resume(async);
3278 		mutex_exit(&asy->asy_excl_hi);
3279 	} else {
3280 		async->async_flags &= ~ASYNC_BUSY;
3281 		mutex_exit(&asy->asy_excl_hi);
3282 		if (async->async_xmitblk != NULL) {
3283 			freeb(async->async_xmitblk);
3284 			async->async_xmitblk = NULL;
3285 		}
3286 		async_start(async);
3287 	}
3288 }
3289 
3290 /*
3291  * Process an "ioctl" message sent down to us.
3292  * Note that we don't need to get any locks until we are ready to access
3293  * the hardware.  Nothing we access until then is going to be altered
3294  * outside of the STREAMS framework, so we should be safe.
3295  */
3296 int asydelay = 10000;
3297 static void
3298 async_ioctl(struct asyncline *async, queue_t *wq, mblk_t *mp)
3299 {
3300 	struct asycom *asy = async->async_common;
3301 	tty_common_t  *tp = &async->async_ttycommon;
3302 	struct iocblk *iocp;
3303 	unsigned datasize;
3304 	int error = 0;
3305 	uchar_t val;
3306 	mblk_t *datamp;
3307 	unsigned int index;
3308 
3309 #ifdef DEBUG
3310 	int instance = UNIT(async->async_dev);
3311 
3312 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl\n", instance);
3313 #endif
3314 
3315 	if (tp->t_iocpending != NULL) {
3316 		/*
3317 		 * We were holding an "ioctl" response pending the
3318 		 * availability of an "mblk" to hold data to be passed up;
3319 		 * another "ioctl" came through, which means that "ioctl"
3320 		 * must have timed out or been aborted.
3321 		 */
3322 		freemsg(async->async_ttycommon.t_iocpending);
3323 		async->async_ttycommon.t_iocpending = NULL;
3324 	}
3325 
3326 	iocp = (struct iocblk *)mp->b_rptr;
3327 
3328 	/*
3329 	 * For TIOCMGET and the PPS ioctls, do NOT call ttycommon_ioctl()
3330 	 * because this function frees up the message block (mp->b_cont) that
3331 	 * contains the user location where we pass back the results.
3332 	 *
3333 	 * Similarly, CONSOPENPOLLEDIO needs ioc_count, which ttycommon_ioctl
3334 	 * zaps.  We know that ttycommon_ioctl doesn't know any CONS*
3335 	 * ioctls, so keep the others safe too.
3336 	 */
3337 	DEBUGCONT2(ASY_DEBUG_IOCTL, "async%d_ioctl: %s\n",
3338 	    instance,
3339 	    iocp->ioc_cmd == TIOCMGET ? "TIOCMGET" :
3340 	    iocp->ioc_cmd == TIOCMSET ? "TIOCMSET" :
3341 	    iocp->ioc_cmd == TIOCMBIS ? "TIOCMBIS" :
3342 	    iocp->ioc_cmd == TIOCMBIC ? "TIOCMBIC" :
3343 	    "other");
3344 
3345 	switch (iocp->ioc_cmd) {
3346 	case TIOCMGET:
3347 	case TIOCGPPS:
3348 	case TIOCSPPS:
3349 	case TIOCGPPSEV:
3350 	case CONSOPENPOLLEDIO:
3351 	case CONSCLOSEPOLLEDIO:
3352 	case CONSSETABORTENABLE:
3353 	case CONSGETABORTENABLE:
3354 		error = -1; /* Do Nothing */
3355 		break;
3356 	default:
3357 
3358 		/*
3359 		 * The only way in which "ttycommon_ioctl" can fail is if the
3360 		 * "ioctl" requires a response containing data to be returned
3361 		 * to the user, and no mblk could be allocated for the data.
3362 		 * No such "ioctl" alters our state.  Thus, we always go ahead
3363 		 * and do any state-changes the "ioctl" calls for.  If we
3364 		 * couldn't allocate the data, "ttycommon_ioctl" has stashed
3365 		 * the "ioctl" away safely, so we just call "bufcall" to
3366 		 * request that we be called back when we stand a better
3367 		 * chance of allocating the data.
3368 		 */
3369 		if ((datasize = ttycommon_ioctl(tp, wq, mp, &error)) != 0) {
3370 			if (async->async_wbufcid)
3371 				unbufcall(async->async_wbufcid);
3372 			async->async_wbufcid = bufcall(datasize, BPRI_HI,
3373 			    (void (*)(void *)) async_reioctl,
3374 			    (void *)(intptr_t)async->async_common->asy_unit);
3375 			return;
3376 		}
3377 	}
3378 
3379 	mutex_enter(&asy->asy_excl);
3380 
3381 	if (error == 0) {
3382 		/*
3383 		 * "ttycommon_ioctl" did most of the work; we just use the
3384 		 * data it set up.
3385 		 */
3386 		switch (iocp->ioc_cmd) {
3387 
3388 		case TCSETS:
3389 			mutex_enter(&asy->asy_excl_hi);
3390 			if (asy_baudok(asy))
3391 				asy_program(asy, ASY_NOINIT);
3392 			else
3393 				error = EINVAL;
3394 			mutex_exit(&asy->asy_excl_hi);
3395 			break;
3396 		case TCSETSF:
3397 		case TCSETSW:
3398 		case TCSETA:
3399 		case TCSETAW:
3400 		case TCSETAF:
3401 			mutex_enter(&asy->asy_excl_hi);
3402 			if (!asy_baudok(asy))
3403 				error = EINVAL;
3404 			else {
3405 				if (asy_isbusy(asy))
3406 					asy_waiteot(asy);
3407 				asy_program(asy, ASY_NOINIT);
3408 			}
3409 			mutex_exit(&asy->asy_excl_hi);
3410 			break;
3411 		}
3412 	} else if (error < 0) {
3413 		/*
3414 		 * "ttycommon_ioctl" didn't do anything; we process it here.
3415 		 */
3416 		error = 0;
3417 		switch (iocp->ioc_cmd) {
3418 
3419 		case TIOCGPPS:
3420 			/*
3421 			 * Get PPS on/off.
3422 			 */
3423 			if (mp->b_cont != NULL)
3424 				freemsg(mp->b_cont);
3425 
3426 			mp->b_cont = allocb(sizeof (int), BPRI_HI);
3427 			if (mp->b_cont == NULL) {
3428 				error = ENOMEM;
3429 				break;
3430 			}
3431 			if (asy->asy_flags & ASY_PPS)
3432 				*(int *)mp->b_cont->b_wptr = 1;
3433 			else
3434 				*(int *)mp->b_cont->b_wptr = 0;
3435 			mp->b_cont->b_wptr += sizeof (int);
3436 			mp->b_datap->db_type = M_IOCACK;
3437 			iocp->ioc_count = sizeof (int);
3438 			break;
3439 
3440 		case TIOCSPPS:
3441 			/*
3442 			 * Set PPS on/off.
3443 			 */
3444 			error = miocpullup(mp, sizeof (int));
3445 			if (error != 0)
3446 				break;
3447 
3448 			mutex_enter(&asy->asy_excl_hi);
3449 			if (*(int *)mp->b_cont->b_rptr)
3450 				asy->asy_flags |= ASY_PPS;
3451 			else
3452 				asy->asy_flags &= ~ASY_PPS;
3453 			/* Reset edge sense */
3454 			asy->asy_flags &= ~ASY_PPS_EDGE;
3455 			mutex_exit(&asy->asy_excl_hi);
3456 			mp->b_datap->db_type = M_IOCACK;
3457 			break;
3458 
3459 		case TIOCGPPSEV:
3460 		{
3461 			/*
3462 			 * Get PPS event data.
3463 			 */
3464 			mblk_t *bp;
3465 			void *buf;
3466 #ifdef _SYSCALL32_IMPL
3467 			struct ppsclockev32 p32;
3468 #endif
3469 			struct ppsclockev ppsclockev;
3470 
3471 			if (mp->b_cont != NULL) {
3472 				freemsg(mp->b_cont);
3473 				mp->b_cont = NULL;
3474 			}
3475 
3476 			if ((asy->asy_flags & ASY_PPS) == 0) {
3477 				error = ENXIO;
3478 				break;
3479 			}
3480 
3481 			/* Protect from incomplete asy_ppsev */
3482 			mutex_enter(&asy->asy_excl_hi);
3483 			ppsclockev = asy_ppsev;
3484 			mutex_exit(&asy->asy_excl_hi);
3485 
3486 #ifdef _SYSCALL32_IMPL
3487 			if ((iocp->ioc_flag & IOC_MODELS) != IOC_NATIVE) {
3488 				TIMEVAL_TO_TIMEVAL32(&p32.tv, &ppsclockev.tv);
3489 				p32.serial = ppsclockev.serial;
3490 				buf = &p32;
3491 				iocp->ioc_count = sizeof (struct ppsclockev32);
3492 			} else
3493 #endif
3494 			{
3495 				buf = &ppsclockev;
3496 				iocp->ioc_count = sizeof (struct ppsclockev);
3497 			}
3498 
3499 			if ((bp = allocb(iocp->ioc_count, BPRI_HI)) == NULL) {
3500 				error = ENOMEM;
3501 				break;
3502 			}
3503 			mp->b_cont = bp;
3504 
3505 			bcopy(buf, bp->b_wptr, iocp->ioc_count);
3506 			bp->b_wptr += iocp->ioc_count;
3507 			mp->b_datap->db_type = M_IOCACK;
3508 			break;
3509 		}
3510 
3511 		case TCSBRK:
3512 			error = miocpullup(mp, sizeof (int));
3513 			if (error != 0)
3514 				break;
3515 
3516 			if (*(int *)mp->b_cont->b_rptr == 0) {
3517 
3518 				/*
3519 				 * XXX Arrangements to ensure that a break
3520 				 * isn't in progress should be sufficient.
3521 				 * This ugly delay() is the only thing
3522 				 * that seems to work on the NCR Worldmark.
3523 				 * It should be replaced. Note that an
3524 				 * asy_waiteot() also does not work.
3525 				 */
3526 				if (asydelay)
3527 					delay(drv_usectohz(asydelay));
3528 
3529 				while (async->async_flags & ASYNC_BREAK) {
3530 					cv_wait(&async->async_flags_cv,
3531 					    &asy->asy_excl);
3532 				}
3533 				mutex_enter(&asy->asy_excl_hi);
3534 				/*
3535 				 * We loop until the TSR is empty and then
3536 				 * set the break.  ASYNC_BREAK has been set
3537 				 * to ensure that no characters are
3538 				 * transmitted while the TSR is being
3539 				 * flushed and SOUT is being used for the
3540 				 * break signal.
3541 				 *
3542 				 * The wait period is equal to
3543 				 * clock / (baud * 16) * 16 * 2.
3544 				 */
3545 				index = BAUDINDEX(
3546 				    async->async_ttycommon.t_cflag);
3547 				async->async_flags |= ASYNC_BREAK;
3548 
3549 				while ((ddi_get8(asy->asy_iohandle,
3550 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3551 					mutex_exit(&asy->asy_excl_hi);
3552 					mutex_exit(&asy->asy_excl);
3553 					drv_usecwait(
3554 					    32*asyspdtab[index] & 0xfff);
3555 					mutex_enter(&asy->asy_excl);
3556 					mutex_enter(&asy->asy_excl_hi);
3557 				}
3558 				/*
3559 				 * Arrange for "async_restart"
3560 				 * to be called in 1/4 second;
3561 				 * it will turn the break bit off, and call
3562 				 * "async_start" to grab the next message.
3563 				 */
3564 				val = ddi_get8(asy->asy_iohandle,
3565 				    asy->asy_ioaddr + LCR);
3566 				ddi_put8(asy->asy_iohandle,
3567 				    asy->asy_ioaddr + LCR,
3568 				    (val | SETBREAK));
3569 				mutex_exit(&asy->asy_excl_hi);
3570 				(void) timeout(async_restart, (caddr_t)async,
3571 				    drv_usectohz(1000000)/4);
3572 			} else {
3573 				DEBUGCONT1(ASY_DEBUG_OUT,
3574 				    "async%d_ioctl: wait for flush.\n",
3575 				    instance);
3576 				mutex_enter(&asy->asy_excl_hi);
3577 				asy_waiteot(asy);
3578 				mutex_exit(&asy->asy_excl_hi);
3579 				DEBUGCONT1(ASY_DEBUG_OUT,
3580 				    "async%d_ioctl: ldterm satisfied.\n",
3581 				    instance);
3582 			}
3583 			break;
3584 
3585 		case TIOCSBRK:
3586 			if (!(async->async_flags & ASYNC_OUT_SUSPEND)) {
3587 				mutex_enter(&asy->asy_excl_hi);
3588 				async->async_flags |= ASYNC_OUT_SUSPEND;
3589 				async->async_flags |= ASYNC_HOLD_UTBRK;
3590 				index = BAUDINDEX(
3591 				    async->async_ttycommon.t_cflag);
3592 				while ((ddi_get8(asy->asy_iohandle,
3593 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3594 					mutex_exit(&asy->asy_excl_hi);
3595 					mutex_exit(&asy->asy_excl);
3596 					drv_usecwait(
3597 					    32*asyspdtab[index] & 0xfff);
3598 					mutex_enter(&asy->asy_excl);
3599 					mutex_enter(&asy->asy_excl_hi);
3600 				}
3601 				val = ddi_get8(asy->asy_iohandle,
3602 				    asy->asy_ioaddr + LCR);
3603 				ddi_put8(asy->asy_iohandle,
3604 				    asy->asy_ioaddr + LCR, (val | SETBREAK));
3605 				mutex_exit(&asy->asy_excl_hi);
3606 				/* wait for 100ms to hold BREAK */
3607 				async->async_utbrktid =
3608 				    timeout((void (*)())async_hold_utbrk,
3609 				    (caddr_t)async,
3610 				    drv_usectohz(asy_min_utbrk));
3611 			}
3612 			mioc2ack(mp, NULL, 0, 0);
3613 			break;
3614 
3615 		case TIOCCBRK:
3616 			if (async->async_flags & ASYNC_OUT_SUSPEND)
3617 				async_resume_utbrk(async);
3618 			mioc2ack(mp, NULL, 0, 0);
3619 			break;
3620 
3621 		case TIOCMSET:
3622 		case TIOCMBIS:
3623 		case TIOCMBIC:
3624 			if (iocp->ioc_count != TRANSPARENT) {
3625 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3626 				    "non-transparent\n", instance);
3627 
3628 				error = miocpullup(mp, sizeof (int));
3629 				if (error != 0)
3630 					break;
3631 
3632 				mutex_enter(&asy->asy_excl_hi);
3633 				(void) asymctl(asy,
3634 				    dmtoasy(*(int *)mp->b_cont->b_rptr),
3635 				    iocp->ioc_cmd);
3636 				mutex_exit(&asy->asy_excl_hi);
3637 				iocp->ioc_error = 0;
3638 				mp->b_datap->db_type = M_IOCACK;
3639 			} else {
3640 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3641 				    "transparent\n", instance);
3642 				mcopyin(mp, NULL, sizeof (int), NULL);
3643 			}
3644 			break;
3645 
3646 		case TIOCMGET:
3647 			datamp = allocb(sizeof (int), BPRI_MED);
3648 			if (datamp == NULL) {
3649 				error = EAGAIN;
3650 				break;
3651 			}
3652 
3653 			mutex_enter(&asy->asy_excl_hi);
3654 			*(int *)datamp->b_rptr = asymctl(asy, 0, TIOCMGET);
3655 			mutex_exit(&asy->asy_excl_hi);
3656 
3657 			if (iocp->ioc_count == TRANSPARENT) {
3658 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3659 				    "transparent\n", instance);
3660 				mcopyout(mp, NULL, sizeof (int), NULL, datamp);
3661 			} else {
3662 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3663 				    "non-transparent\n", instance);
3664 				mioc2ack(mp, datamp, sizeof (int), 0);
3665 			}
3666 			break;
3667 
3668 		case CONSOPENPOLLEDIO:
3669 			error = miocpullup(mp, sizeof (struct cons_polledio *));
3670 			if (error != 0)
3671 				break;
3672 
3673 			*(struct cons_polledio **)mp->b_cont->b_rptr =
3674 			    &asy->polledio;
3675 
3676 			mp->b_datap->db_type = M_IOCACK;
3677 			break;
3678 
3679 		case CONSCLOSEPOLLEDIO:
3680 			mp->b_datap->db_type = M_IOCACK;
3681 			iocp->ioc_error = 0;
3682 			iocp->ioc_rval = 0;
3683 			break;
3684 
3685 		case CONSSETABORTENABLE:
3686 			error = secpolicy_console(iocp->ioc_cr);
3687 			if (error != 0)
3688 				break;
3689 
3690 			if (iocp->ioc_count != TRANSPARENT) {
3691 				error = EINVAL;
3692 				break;
3693 			}
3694 
3695 			if (*(intptr_t *)mp->b_cont->b_rptr)
3696 				asy->asy_flags |= ASY_CONSOLE;
3697 			else
3698 				asy->asy_flags &= ~ASY_CONSOLE;
3699 
3700 			mp->b_datap->db_type = M_IOCACK;
3701 			iocp->ioc_error = 0;
3702 			iocp->ioc_rval = 0;
3703 			break;
3704 
3705 		case CONSGETABORTENABLE:
3706 			/*CONSTANTCONDITION*/
3707 			ASSERT(sizeof (boolean_t) <= sizeof (boolean_t *));
3708 			/*
3709 			 * Store the return value right in the payload
3710 			 * we were passed.  Crude.
3711 			 */
3712 			mcopyout(mp, NULL, sizeof (boolean_t), NULL, NULL);
3713 			*(boolean_t *)mp->b_cont->b_rptr =
3714 			    (asy->asy_flags & ASY_CONSOLE) != 0;
3715 			break;
3716 
3717 		default:
3718 			/*
3719 			 * If we don't understand it, it's an error.  NAK it.
3720 			 */
3721 			error = EINVAL;
3722 			break;
3723 		}
3724 	}
3725 	if (error != 0) {
3726 		iocp->ioc_error = error;
3727 		mp->b_datap->db_type = M_IOCNAK;
3728 	}
3729 	mutex_exit(&asy->asy_excl);
3730 	qreply(wq, mp);
3731 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl: done\n", instance);
3732 }
3733 
3734 static int
3735 asyrsrv(queue_t *q)
3736 {
3737 	mblk_t *bp;
3738 	struct asyncline *async;
3739 
3740 	async = (struct asyncline *)q->q_ptr;
3741 
3742 	while (canputnext(q) && (bp = getq(q)))
3743 		putnext(q, bp);
3744 	ASYSETSOFT(async->async_common);
3745 	async->async_polltid = 0;
3746 	return (0);
3747 }
3748 
3749 /*
3750  * The ASYWPUTDO_NOT_SUSP macro indicates to asywputdo() whether it should
3751  * handle messages as though the driver is operating normally or is
3752  * suspended.  In the suspended case, some or all of the processing may have
3753  * to be delayed until the driver is resumed.
3754  */
3755 #define	ASYWPUTDO_NOT_SUSP(async, wput) \
3756 	!((wput) && ((async)->async_flags & ASYNC_DDI_SUSPENDED))
3757 
3758 /*
3759  * Processing for write queue put procedure.
3760  * Respond to M_STOP, M_START, M_IOCTL, and M_FLUSH messages here;
3761  * set the flow control character for M_STOPI and M_STARTI messages;
3762  * queue up M_BREAK, M_DELAY, and M_DATA messages for processing
3763  * by the start routine, and then call the start routine; discard
3764  * everything else.  Note that this driver does not incorporate any
3765  * mechanism to negotiate to handle the canonicalization process.
3766  * It expects that these functions are handled in upper module(s),
3767  * as we do in ldterm.
3768  */
3769 static int
3770 asywputdo(queue_t *q, mblk_t *mp, boolean_t wput)
3771 {
3772 	struct asyncline *async;
3773 	struct asycom *asy;
3774 #ifdef DEBUG
3775 	int instance;
3776 #endif
3777 	int error;
3778 
3779 	async = (struct asyncline *)q->q_ptr;
3780 
3781 #ifdef DEBUG
3782 	instance = UNIT(async->async_dev);
3783 #endif
3784 	asy = async->async_common;
3785 
3786 	switch (mp->b_datap->db_type) {
3787 
3788 	case M_STOP:
3789 		/*
3790 		 * Since we don't do real DMA, we can just let the
3791 		 * chip coast to a stop after applying the brakes.
3792 		 */
3793 		mutex_enter(&asy->asy_excl);
3794 		async->async_flags |= ASYNC_STOPPED;
3795 		mutex_exit(&asy->asy_excl);
3796 		freemsg(mp);
3797 		break;
3798 
3799 	case M_START:
3800 		mutex_enter(&asy->asy_excl);
3801 		if (async->async_flags & ASYNC_STOPPED) {
3802 			async->async_flags &= ~ASYNC_STOPPED;
3803 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3804 				/*
3805 				 * If an output operation is in progress,
3806 				 * resume it.  Otherwise, prod the start
3807 				 * routine.
3808 				 */
3809 				if (async->async_ocnt > 0) {
3810 					mutex_enter(&asy->asy_excl_hi);
3811 					async_resume(async);
3812 					mutex_exit(&asy->asy_excl_hi);
3813 				} else {
3814 					async_start(async);
3815 				}
3816 			}
3817 		}
3818 		mutex_exit(&asy->asy_excl);
3819 		freemsg(mp);
3820 		break;
3821 
3822 	case M_IOCTL:
3823 		switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
3824 
3825 		case TCSBRK:
3826 			error = miocpullup(mp, sizeof (int));
3827 			if (error != 0) {
3828 				miocnak(q, mp, 0, error);
3829 				return (0);
3830 			}
3831 
3832 			if (*(int *)mp->b_cont->b_rptr != 0) {
3833 				DEBUGCONT1(ASY_DEBUG_OUT,
3834 				    "async%d_ioctl: flush request.\n",
3835 				    instance);
3836 				(void) putq(q, mp);
3837 
3838 				mutex_enter(&asy->asy_excl);
3839 				if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3840 					/*
3841 					 * If an TIOCSBRK is in progress,
3842 					 * clean it as TIOCCBRK does,
3843 					 * then kick off output.
3844 					 * If TIOCSBRK is not in progress,
3845 					 * just kick off output.
3846 					 */
3847 					async_resume_utbrk(async);
3848 				}
3849 				mutex_exit(&asy->asy_excl);
3850 				break;
3851 			}
3852 			/*FALLTHROUGH*/
3853 		case TCSETSW:
3854 		case TCSETSF:
3855 		case TCSETAW:
3856 		case TCSETAF:
3857 			/*
3858 			 * The changes do not take effect until all
3859 			 * output queued before them is drained.
3860 			 * Put this message on the queue, so that
3861 			 * "async_start" will see it when it's done
3862 			 * with the output before it.  Poke the
3863 			 * start routine, just in case.
3864 			 */
3865 			(void) putq(q, mp);
3866 
3867 			mutex_enter(&asy->asy_excl);
3868 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3869 				/*
3870 				 * If an TIOCSBRK is in progress,
3871 				 * clean it as TIOCCBRK does.
3872 				 * then kick off output.
3873 				 * If TIOCSBRK is not in progress,
3874 				 * just kick off output.
3875 				 */
3876 				async_resume_utbrk(async);
3877 			}
3878 			mutex_exit(&asy->asy_excl);
3879 			break;
3880 
3881 		default:
3882 			/*
3883 			 * Do it now.
3884 			 */
3885 			mutex_enter(&asy->asy_excl);
3886 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3887 				mutex_exit(&asy->asy_excl);
3888 				async_ioctl(async, q, mp);
3889 				break;
3890 			}
3891 			async_put_suspq(asy, mp);
3892 			mutex_exit(&asy->asy_excl);
3893 			break;
3894 		}
3895 		break;
3896 
3897 	case M_FLUSH:
3898 		if (*mp->b_rptr & FLUSHW) {
3899 			mutex_enter(&asy->asy_excl);
3900 
3901 			/*
3902 			 * Abort any output in progress.
3903 			 */
3904 			mutex_enter(&asy->asy_excl_hi);
3905 			if (async->async_flags & ASYNC_BUSY) {
3906 				DEBUGCONT1(ASY_DEBUG_BUSY, "asy%dwput: "
3907 				    "Clearing async_ocnt, "
3908 				    "leaving ASYNC_BUSY set\n",
3909 				    instance);
3910 				async->async_ocnt = 0;
3911 				async->async_flags &= ~ASYNC_BUSY;
3912 			} /* if */
3913 
3914 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3915 				/* Flush FIFO buffers */
3916 				if (asy->asy_use_fifo == FIFO_ON) {
3917 					asy_reset_fifo(asy, FIFOTXFLSH);
3918 				}
3919 			}
3920 			mutex_exit(&asy->asy_excl_hi);
3921 
3922 			/* Flush FIFO buffers */
3923 			if (asy->asy_use_fifo == FIFO_ON) {
3924 				asy_reset_fifo(asy, FIFOTXFLSH);
3925 			}
3926 
3927 			/*
3928 			 * Flush our write queue.
3929 			 */
3930 			flushq(q, FLUSHDATA);	/* XXX doesn't flush M_DELAY */
3931 			if (async->async_xmitblk != NULL) {
3932 				freeb(async->async_xmitblk);
3933 				async->async_xmitblk = NULL;
3934 			}
3935 			mutex_exit(&asy->asy_excl);
3936 			*mp->b_rptr &= ~FLUSHW;	/* it has been flushed */
3937 		}
3938 		if (*mp->b_rptr & FLUSHR) {
3939 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3940 				/* Flush FIFO buffers */
3941 				if (asy->asy_use_fifo == FIFO_ON) {
3942 					asy_reset_fifo(asy, FIFORXFLSH);
3943 				}
3944 			}
3945 			flushq(RD(q), FLUSHDATA);
3946 			qreply(q, mp);	/* give the read queues a crack at it */
3947 		} else {
3948 			freemsg(mp);
3949 		}
3950 
3951 		/*
3952 		 * We must make sure we process messages that survive the
3953 		 * write-side flush.
3954 		 */
3955 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3956 			mutex_enter(&asy->asy_excl);
3957 			async_start(async);
3958 			mutex_exit(&asy->asy_excl);
3959 		}
3960 		break;
3961 
3962 	case M_BREAK:
3963 	case M_DELAY:
3964 	case M_DATA:
3965 		/*
3966 		 * Queue the message up to be transmitted,
3967 		 * and poke the start routine.
3968 		 */
3969 		(void) putq(q, mp);
3970 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3971 			mutex_enter(&asy->asy_excl);
3972 			async_start(async);
3973 			mutex_exit(&asy->asy_excl);
3974 		}
3975 		break;
3976 
3977 	case M_STOPI:
3978 		mutex_enter(&asy->asy_excl);
3979 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3980 			mutex_enter(&asy->asy_excl_hi);
3981 			if (!(async->async_inflow_source & IN_FLOW_USER)) {
3982 				async_flowcontrol_hw_input(asy, FLOW_STOP,
3983 				    IN_FLOW_USER);
3984 				(void) async_flowcontrol_sw_input(asy,
3985 				    FLOW_STOP, IN_FLOW_USER);
3986 			}
3987 			mutex_exit(&asy->asy_excl_hi);
3988 			mutex_exit(&asy->asy_excl);
3989 			freemsg(mp);
3990 			break;
3991 		}
3992 		async_put_suspq(asy, mp);
3993 		mutex_exit(&asy->asy_excl);
3994 		break;
3995 
3996 	case M_STARTI:
3997 		mutex_enter(&asy->asy_excl);
3998 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3999 			mutex_enter(&asy->asy_excl_hi);
4000 			if (async->async_inflow_source & IN_FLOW_USER) {
4001 				async_flowcontrol_hw_input(asy, FLOW_START,
4002 				    IN_FLOW_USER);
4003 				(void) async_flowcontrol_sw_input(asy,
4004 				    FLOW_START, IN_FLOW_USER);
4005 			}
4006 			mutex_exit(&asy->asy_excl_hi);
4007 			mutex_exit(&asy->asy_excl);
4008 			freemsg(mp);
4009 			break;
4010 		}
4011 		async_put_suspq(asy, mp);
4012 		mutex_exit(&asy->asy_excl);
4013 		break;
4014 
4015 	case M_CTL:
4016 		if (MBLKL(mp) >= sizeof (struct iocblk) &&
4017 		    ((struct iocblk *)mp->b_rptr)->ioc_cmd == MC_POSIXQUERY) {
4018 			mutex_enter(&asy->asy_excl);
4019 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4020 				((struct iocblk *)mp->b_rptr)->ioc_cmd =
4021 				    MC_HAS_POSIX;
4022 				mutex_exit(&asy->asy_excl);
4023 				qreply(q, mp);
4024 				break;
4025 			} else {
4026 				async_put_suspq(asy, mp);
4027 			}
4028 		} else {
4029 			/*
4030 			 * These MC_SERVICE type messages are used by upper
4031 			 * modules to tell this driver to send input up
4032 			 * immediately, or that it can wait for normal
4033 			 * processing that may or may not be done.  Sun
4034 			 * requires these for the mouse module.
4035 			 * (XXX - for x86?)
4036 			 */
4037 			mutex_enter(&asy->asy_excl);
4038 			switch (*mp->b_rptr) {
4039 
4040 			case MC_SERVICEIMM:
4041 				async->async_flags |= ASYNC_SERVICEIMM;
4042 				break;
4043 
4044 			case MC_SERVICEDEF:
4045 				async->async_flags &= ~ASYNC_SERVICEIMM;
4046 				break;
4047 			}
4048 			mutex_exit(&asy->asy_excl);
4049 			freemsg(mp);
4050 		}
4051 		break;
4052 
4053 	case M_IOCDATA:
4054 		mutex_enter(&asy->asy_excl);
4055 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4056 			mutex_exit(&asy->asy_excl);
4057 			async_iocdata(q, mp);
4058 			break;
4059 		}
4060 		async_put_suspq(asy, mp);
4061 		mutex_exit(&asy->asy_excl);
4062 		break;
4063 
4064 	default:
4065 		freemsg(mp);
4066 		break;
4067 	}
4068 	return (0);
4069 }
4070 
4071 static int
4072 asywput(queue_t *q, mblk_t *mp)
4073 {
4074 	return (asywputdo(q, mp, B_TRUE));
4075 }
4076 
4077 /*
4078  * Retry an "ioctl", now that "bufcall" claims we may be able to allocate
4079  * the buffer we need.
4080  */
4081 static void
4082 async_reioctl(void *unit)
4083 {
4084 	int instance = (uintptr_t)unit;
4085 	struct asyncline *async;
4086 	struct asycom *asy;
4087 	queue_t	*q;
4088 	mblk_t	*mp;
4089 
4090 	asy = ddi_get_soft_state(asy_soft_state, instance);
4091 	ASSERT(asy != NULL);
4092 	async = asy->asy_priv;
4093 
4094 	/*
4095 	 * The bufcall is no longer pending.
4096 	 */
4097 	mutex_enter(&asy->asy_excl);
4098 	async->async_wbufcid = 0;
4099 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
4100 		mutex_exit(&asy->asy_excl);
4101 		return;
4102 	}
4103 	if ((mp = async->async_ttycommon.t_iocpending) != NULL) {
4104 		/* not pending any more */
4105 		async->async_ttycommon.t_iocpending = NULL;
4106 		mutex_exit(&asy->asy_excl);
4107 		async_ioctl(async, q, mp);
4108 	} else
4109 		mutex_exit(&asy->asy_excl);
4110 }
4111 
4112 static void
4113 async_iocdata(queue_t *q, mblk_t *mp)
4114 {
4115 	struct asyncline	*async = (struct asyncline *)q->q_ptr;
4116 	struct asycom		*asy;
4117 	struct iocblk *ip;
4118 	struct copyresp *csp;
4119 #ifdef DEBUG
4120 	int instance = UNIT(async->async_dev);
4121 #endif
4122 
4123 	asy = async->async_common;
4124 	ip = (struct iocblk *)mp->b_rptr;
4125 	csp = (struct copyresp *)mp->b_rptr;
4126 
4127 	if (csp->cp_rval != 0) {
4128 		if (csp->cp_private)
4129 			freemsg(csp->cp_private);
4130 		freemsg(mp);
4131 		return;
4132 	}
4133 
4134 	mutex_enter(&asy->asy_excl);
4135 	DEBUGCONT2(ASY_DEBUG_MODEM, "async%d_iocdata: case %s\n",
4136 	    instance,
4137 	    csp->cp_cmd == TIOCMGET ? "TIOCMGET" :
4138 	    csp->cp_cmd == TIOCMSET ? "TIOCMSET" :
4139 	    csp->cp_cmd == TIOCMBIS ? "TIOCMBIS" :
4140 	    "TIOCMBIC");
4141 	switch (csp->cp_cmd) {
4142 
4143 	case TIOCMGET:
4144 		if (mp->b_cont) {
4145 			freemsg(mp->b_cont);
4146 			mp->b_cont = NULL;
4147 		}
4148 		mp->b_datap->db_type = M_IOCACK;
4149 		ip->ioc_error = 0;
4150 		ip->ioc_count = 0;
4151 		ip->ioc_rval = 0;
4152 		mp->b_wptr = mp->b_rptr + sizeof (struct iocblk);
4153 		break;
4154 
4155 	case TIOCMSET:
4156 	case TIOCMBIS:
4157 	case TIOCMBIC:
4158 		mutex_enter(&asy->asy_excl_hi);
4159 		(void) asymctl(asy, dmtoasy(*(int *)mp->b_cont->b_rptr),
4160 		    csp->cp_cmd);
4161 		mutex_exit(&asy->asy_excl_hi);
4162 		mioc2ack(mp, NULL, 0, 0);
4163 		break;
4164 
4165 	default:
4166 		mp->b_datap->db_type = M_IOCNAK;
4167 		ip->ioc_error = EINVAL;
4168 		break;
4169 	}
4170 	qreply(q, mp);
4171 	mutex_exit(&asy->asy_excl);
4172 }
4173 
4174 /*
4175  * debugger/console support routines.
4176  */
4177 
4178 /*
4179  * put a character out
4180  * Do not use interrupts.  If char is LF, put out CR, LF.
4181  */
4182 static void
4183 asyputchar(cons_polledio_arg_t arg, uchar_t c)
4184 {
4185 	struct asycom *asy = (struct asycom *)arg;
4186 
4187 	if (c == '\n')
4188 		asyputchar(arg, '\r');
4189 
4190 	while ((ddi_get8(asy->asy_iohandle,
4191 	    asy->asy_ioaddr + LSR) & XHRE) == 0) {
4192 		/* wait for xmit to finish */
4193 		drv_usecwait(10);
4194 	}
4195 
4196 	/* put the character out */
4197 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT, c);
4198 }
4199 
4200 /*
4201  * See if there's a character available. If no character is
4202  * available, return 0. Run in polled mode, no interrupts.
4203  */
4204 static boolean_t
4205 asyischar(cons_polledio_arg_t arg)
4206 {
4207 	struct asycom *asy = (struct asycom *)arg;
4208 
4209 	return ((ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & RCA)
4210 	    != 0);
4211 }
4212 
4213 /*
4214  * Get a character. Run in polled mode, no interrupts.
4215  */
4216 static int
4217 asygetchar(cons_polledio_arg_t arg)
4218 {
4219 	struct asycom *asy = (struct asycom *)arg;
4220 
4221 	while (!asyischar(arg))
4222 		drv_usecwait(10);
4223 	return (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + DAT));
4224 }
4225 
4226 /*
4227  * Set or get the modem control status.
4228  */
4229 static int
4230 asymctl(struct asycom *asy, int bits, int how)
4231 {
4232 	int mcr_r, msr_r;
4233 	int instance = asy->asy_unit;
4234 
4235 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4236 	ASSERT(mutex_owned(&asy->asy_excl));
4237 
4238 	/* Read Modem Control Registers */
4239 	mcr_r = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4240 
4241 	switch (how) {
4242 
4243 	case TIOCMSET:
4244 		DEBUGCONT2(ASY_DEBUG_MODEM,
4245 		    "asy%dmctl: TIOCMSET, bits = %x\n", instance, bits);
4246 		mcr_r = bits;		/* Set bits	*/
4247 		break;
4248 
4249 	case TIOCMBIS:
4250 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIS, bits = %x\n",
4251 		    instance, bits);
4252 		mcr_r |= bits;		/* Mask in bits	*/
4253 		break;
4254 
4255 	case TIOCMBIC:
4256 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIC, bits = %x\n",
4257 		    instance, bits);
4258 		mcr_r &= ~bits;		/* Mask out bits */
4259 		break;
4260 
4261 	case TIOCMGET:
4262 		/* Read Modem Status Registers */
4263 		/*
4264 		 * If modem interrupts are enabled, we return the
4265 		 * saved value of msr. We read MSR only in async_msint()
4266 		 */
4267 		if (ddi_get8(asy->asy_iohandle,
4268 		    asy->asy_ioaddr + ICR) & MIEN) {
4269 			msr_r = asy->asy_msr;
4270 			DEBUGCONT2(ASY_DEBUG_MODEM,
4271 			    "asy%dmctl: TIOCMGET, read msr_r = %x\n",
4272 			    instance, msr_r);
4273 		} else {
4274 			msr_r = ddi_get8(asy->asy_iohandle,
4275 			    asy->asy_ioaddr + MSR);
4276 			DEBUGCONT2(ASY_DEBUG_MODEM,
4277 			    "asy%dmctl: TIOCMGET, read MSR = %x\n",
4278 			    instance, msr_r);
4279 		}
4280 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dtodm: modem_lines = %x\n",
4281 		    instance, asytodm(mcr_r, msr_r));
4282 		return (asytodm(mcr_r, msr_r));
4283 	}
4284 
4285 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr_r);
4286 
4287 	return (mcr_r);
4288 }
4289 
4290 static int
4291 asytodm(int mcr_r, int msr_r)
4292 {
4293 	int b = 0;
4294 
4295 	/* MCR registers */
4296 	if (mcr_r & RTS)
4297 		b |= TIOCM_RTS;
4298 
4299 	if (mcr_r & DTR)
4300 		b |= TIOCM_DTR;
4301 
4302 	/* MSR registers */
4303 	if (msr_r & DCD)
4304 		b |= TIOCM_CAR;
4305 
4306 	if (msr_r & CTS)
4307 		b |= TIOCM_CTS;
4308 
4309 	if (msr_r & DSR)
4310 		b |= TIOCM_DSR;
4311 
4312 	if (msr_r & RI)
4313 		b |= TIOCM_RNG;
4314 	return (b);
4315 }
4316 
4317 static int
4318 dmtoasy(int bits)
4319 {
4320 	int b = 0;
4321 
4322 	DEBUGCONT1(ASY_DEBUG_MODEM, "dmtoasy: bits = %x\n", bits);
4323 #ifdef	CAN_NOT_SET	/* only DTR and RTS can be set */
4324 	if (bits & TIOCM_CAR)
4325 		b |= DCD;
4326 	if (bits & TIOCM_CTS)
4327 		b |= CTS;
4328 	if (bits & TIOCM_DSR)
4329 		b |= DSR;
4330 	if (bits & TIOCM_RNG)
4331 		b |= RI;
4332 #endif
4333 
4334 	if (bits & TIOCM_RTS) {
4335 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & RTS\n");
4336 		b |= RTS;
4337 	}
4338 	if (bits & TIOCM_DTR) {
4339 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & DTR\n");
4340 		b |= DTR;
4341 	}
4342 
4343 	return (b);
4344 }
4345 
4346 static void
4347 asyerror(int level, const char *fmt, ...)
4348 {
4349 	va_list adx;
4350 	static	time_t	last;
4351 	static	const char *lastfmt;
4352 	time_t	now;
4353 
4354 	/*
4355 	 * Don't print the same error message too often.
4356 	 * Print the message only if we have not printed the
4357 	 * message within the last second.
4358 	 * Note: that fmt cannot be a pointer to a string
4359 	 * stored on the stack. The fmt pointer
4360 	 * must be in the data segment otherwise lastfmt would point
4361 	 * to non-sense.
4362 	 */
4363 	now = gethrestime_sec();
4364 	if (last == now && lastfmt == fmt)
4365 		return;
4366 
4367 	last = now;
4368 	lastfmt = fmt;
4369 
4370 	va_start(adx, fmt);
4371 	vcmn_err(level, fmt, adx);
4372 	va_end(adx);
4373 }
4374 
4375 /*
4376  * asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4377  * The value of this property is in the form of "9600,8,n,1,-"
4378  * 1) speed: 9600, 4800, ...
4379  * 2) data bits
4380  * 3) parity: n(none), e(even), o(odd)
4381  * 4) stop bits
4382  * 5) handshake: -(none), h(hardware: rts/cts), s(software: xon/off)
4383  *
4384  * This parsing came from a SPARCstation eeprom.
4385  */
4386 static void
4387 asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4388 {
4389 	char		name[40];
4390 	char		val[40];
4391 	int		len;
4392 	int		ret;
4393 	char		*p;
4394 	char		*p1;
4395 
4396 	ASSERT(asy->asy_com_port != 0);
4397 
4398 	/*
4399 	 * Parse the ttyx-mode property
4400 	 */
4401 	(void) sprintf(name, "tty%c-mode", asy->asy_com_port + 'a' - 1);
4402 	len = sizeof (val);
4403 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4404 	if (ret != DDI_PROP_SUCCESS) {
4405 		(void) sprintf(name, "com%c-mode", asy->asy_com_port + '0');
4406 		len = sizeof (val);
4407 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4408 	}
4409 
4410 	/* no property to parse */
4411 	asy->asy_cflag = 0;
4412 	if (ret != DDI_PROP_SUCCESS)
4413 		return;
4414 
4415 	p = val;
4416 	/* ---- baud rate ---- */
4417 	asy->asy_cflag = CREAD|B9600;		/* initial default */
4418 	if (p && (p1 = strchr(p, ',')) != 0) {
4419 		*p1++ = '\0';
4420 	} else {
4421 		asy->asy_cflag |= BITS8;	/* add default bits */
4422 		return;
4423 	}
4424 
4425 	if (strcmp(p, "110") == 0)
4426 		asy->asy_bidx = B110;
4427 	else if (strcmp(p, "150") == 0)
4428 		asy->asy_bidx = B150;
4429 	else if (strcmp(p, "300") == 0)
4430 		asy->asy_bidx = B300;
4431 	else if (strcmp(p, "600") == 0)
4432 		asy->asy_bidx = B600;
4433 	else if (strcmp(p, "1200") == 0)
4434 		asy->asy_bidx = B1200;
4435 	else if (strcmp(p, "2400") == 0)
4436 		asy->asy_bidx = B2400;
4437 	else if (strcmp(p, "4800") == 0)
4438 		asy->asy_bidx = B4800;
4439 	else if (strcmp(p, "9600") == 0)
4440 		asy->asy_bidx = B9600;
4441 	else if (strcmp(p, "19200") == 0)
4442 		asy->asy_bidx = B19200;
4443 	else if (strcmp(p, "38400") == 0)
4444 		asy->asy_bidx = B38400;
4445 	else if (strcmp(p, "57600") == 0)
4446 		asy->asy_bidx = B57600;
4447 	else if (strcmp(p, "115200") == 0)
4448 		asy->asy_bidx = B115200;
4449 	else
4450 		asy->asy_bidx = B9600;
4451 
4452 	asy->asy_cflag &= ~CBAUD;
4453 	if (asy->asy_bidx > CBAUD) {	/* > 38400 uses the CBAUDEXT bit */
4454 		asy->asy_cflag |= CBAUDEXT;
4455 		asy->asy_cflag |= asy->asy_bidx - CBAUD - 1;
4456 	} else {
4457 		asy->asy_cflag |= asy->asy_bidx;
4458 	}
4459 
4460 	ASSERT(asy->asy_bidx == BAUDINDEX(asy->asy_cflag));
4461 
4462 	/* ---- Next item is data bits ---- */
4463 	p = p1;
4464 	if (p && (p1 = strchr(p, ',')) != 0)  {
4465 		*p1++ = '\0';
4466 	} else {
4467 		asy->asy_cflag |= BITS8;	/* add default bits */
4468 		return;
4469 	}
4470 	switch (*p) {
4471 		default:
4472 		case '8':
4473 			asy->asy_cflag |= CS8;
4474 			asy->asy_lcr = BITS8;
4475 			break;
4476 		case '7':
4477 			asy->asy_cflag |= CS7;
4478 			asy->asy_lcr = BITS7;
4479 			break;
4480 		case '6':
4481 			asy->asy_cflag |= CS6;
4482 			asy->asy_lcr = BITS6;
4483 			break;
4484 		case '5':
4485 			/* LINTED: CS5 is currently zero (but might change) */
4486 			asy->asy_cflag |= CS5;
4487 			asy->asy_lcr = BITS5;
4488 			break;
4489 	}
4490 
4491 	/* ---- Parity info ---- */
4492 	p = p1;
4493 	if (p && (p1 = strchr(p, ',')) != 0)  {
4494 		*p1++ = '\0';
4495 	} else {
4496 		return;
4497 	}
4498 	switch (*p)  {
4499 		default:
4500 		case 'n':
4501 			break;
4502 		case 'e':
4503 			asy->asy_cflag |= PARENB;
4504 			asy->asy_lcr |= PEN; break;
4505 		case 'o':
4506 			asy->asy_cflag |= PARENB|PARODD;
4507 			asy->asy_lcr |= PEN|EPS;
4508 			break;
4509 	}
4510 
4511 	/* ---- Find stop bits ---- */
4512 	p = p1;
4513 	if (p && (p1 = strchr(p, ',')) != 0)  {
4514 		*p1++ = '\0';
4515 	} else {
4516 		return;
4517 	}
4518 	if (*p == '2') {
4519 		asy->asy_cflag |= CSTOPB;
4520 		asy->asy_lcr |= STB;
4521 	}
4522 
4523 	/* ---- handshake is next ---- */
4524 	p = p1;
4525 	if (p) {
4526 		if ((p1 = strchr(p, ',')) != 0)
4527 			*p1++ = '\0';
4528 
4529 		if (*p == 'h')
4530 			asy->asy_cflag |= CRTSCTS;
4531 		else if (*p == 's')
4532 			asy->asy_cflag |= CRTSXOFF;
4533 	}
4534 }
4535 
4536 /*
4537  * Check for abort character sequence
4538  */
4539 static boolean_t
4540 abort_charseq_recognize(uchar_t ch)
4541 {
4542 	static int state = 0;
4543 #define	CNTRL(c) ((c)&037)
4544 	static char sequence[] = { '\r', '~', CNTRL('b') };
4545 
4546 	if (ch == sequence[state]) {
4547 		if (++state >= sizeof (sequence)) {
4548 			state = 0;
4549 			return (B_TRUE);
4550 		}
4551 	} else {
4552 		state = (ch == sequence[0]) ? 1 : 0;
4553 	}
4554 	return (B_FALSE);
4555 }
4556 
4557 /*
4558  * Flow control functions
4559  */
4560 /*
4561  * Software input flow control
4562  * This function can execute software input flow control sucessfully
4563  * at most of situations except that the line is in BREAK status
4564  * (timed and untimed break).
4565  * INPUT VALUE of onoff:
4566  *               FLOW_START means to send out a XON char
4567  *                          and clear SW input flow control flag.
4568  *               FLOW_STOP means to send out a XOFF char
4569  *                          and set SW input flow control flag.
4570  *               FLOW_CHECK means to check whether there is pending XON/XOFF
4571  *                          if it is true, send it out.
4572  * INPUT VALUE of type:
4573  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4574  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4575  *		 IN_FLOW_USER means flow control is due to user's commands
4576  * RETURN VALUE: B_FALSE means no flow control char is sent
4577  *               B_TRUE means one flow control char is sent
4578  */
4579 static boolean_t
4580 async_flowcontrol_sw_input(struct asycom *asy, async_flowc_action onoff,
4581     int type)
4582 {
4583 	struct asyncline *async = asy->asy_priv;
4584 	int instance = UNIT(async->async_dev);
4585 	int rval = B_FALSE;
4586 
4587 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4588 
4589 	if (!(async->async_ttycommon.t_iflag & IXOFF))
4590 		return (rval);
4591 
4592 	/*
4593 	 * If we get this far, then we know IXOFF is set.
4594 	 */
4595 	switch (onoff) {
4596 	case FLOW_STOP:
4597 		async->async_inflow_source |= type;
4598 
4599 		/*
4600 		 * We'll send an XOFF character for each of up to
4601 		 * three different input flow control attempts to stop input.
4602 		 * If we already send out one XOFF, but FLOW_STOP comes again,
4603 		 * it seems that input flow control becomes more serious,
4604 		 * then send XOFF again.
4605 		 */
4606 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4607 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4608 			async->async_flags |= ASYNC_SW_IN_FLOW |
4609 			    ASYNC_SW_IN_NEEDED;
4610 		DEBUGCONT2(ASY_DEBUG_SFLOW, "async%d: input sflow stop, "
4611 		    "type = %x\n", instance, async->async_inflow_source);
4612 		break;
4613 	case FLOW_START:
4614 		async->async_inflow_source &= ~type;
4615 		if (async->async_inflow_source == 0) {
4616 			async->async_flags = (async->async_flags &
4617 			    ~ASYNC_SW_IN_FLOW) | ASYNC_SW_IN_NEEDED;
4618 			DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: "
4619 			    "input sflow start\n", instance);
4620 		}
4621 		break;
4622 	default:
4623 		break;
4624 	}
4625 
4626 	if (((async->async_flags & (ASYNC_SW_IN_NEEDED | ASYNC_BREAK |
4627 	    ASYNC_OUT_SUSPEND)) == ASYNC_SW_IN_NEEDED) &&
4628 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE)) {
4629 		/*
4630 		 * If we get this far, then we know we need to send out
4631 		 * XON or XOFF char.
4632 		 */
4633 		async->async_flags = (async->async_flags &
4634 		    ~ASYNC_SW_IN_NEEDED) | ASYNC_BUSY;
4635 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
4636 		    async->async_flags & ASYNC_SW_IN_FLOW ?
4637 		    async->async_stopc : async->async_startc);
4638 		rval = B_TRUE;
4639 	}
4640 	return (rval);
4641 }
4642 
4643 /*
4644  * Software output flow control
4645  * This function can be executed sucessfully at any situation.
4646  * It does not handle HW, and just change the SW output flow control flag.
4647  * INPUT VALUE of onoff:
4648  *                 FLOW_START means to clear SW output flow control flag,
4649  *			also combine with HW output flow control status to
4650  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4651  *                 FLOW_STOP means to set SW output flow control flag,
4652  *			also clear ASYNC_OUT_FLW_RESUME.
4653  */
4654 static void
4655 async_flowcontrol_sw_output(struct asycom *asy, async_flowc_action onoff)
4656 {
4657 	struct asyncline *async = asy->asy_priv;
4658 	int instance = UNIT(async->async_dev);
4659 
4660 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4661 
4662 	if (!(async->async_ttycommon.t_iflag & IXON))
4663 		return;
4664 
4665 	switch (onoff) {
4666 	case FLOW_STOP:
4667 		async->async_flags |= ASYNC_SW_OUT_FLW;
4668 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4669 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow stop\n",
4670 		    instance);
4671 		break;
4672 	case FLOW_START:
4673 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
4674 		if (!(async->async_flags & ASYNC_HW_OUT_FLW))
4675 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4676 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow start\n",
4677 		    instance);
4678 		break;
4679 	default:
4680 		break;
4681 	}
4682 }
4683 
4684 /*
4685  * Hardware input flow control
4686  * This function can be executed sucessfully at any situation.
4687  * It directly changes RTS depending on input parameter onoff.
4688  * INPUT VALUE of onoff:
4689  *       FLOW_START means to clear HW input flow control flag,
4690  *                  and pull up RTS if it is low.
4691  *       FLOW_STOP means to set HW input flow control flag,
4692  *                  and low RTS if it is high.
4693  * INPUT VALUE of type:
4694  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4695  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4696  *		 IN_FLOW_USER means flow control is due to user's commands
4697  */
4698 static void
4699 async_flowcontrol_hw_input(struct asycom *asy, async_flowc_action onoff,
4700     int type)
4701 {
4702 	uchar_t	mcr;
4703 	uchar_t	flag;
4704 	struct asyncline *async = asy->asy_priv;
4705 	int instance = UNIT(async->async_dev);
4706 
4707 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4708 
4709 	if (!(async->async_ttycommon.t_cflag & CRTSXOFF))
4710 		return;
4711 
4712 	switch (onoff) {
4713 	case FLOW_STOP:
4714 		async->async_inflow_source |= type;
4715 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4716 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4717 			async->async_flags |= ASYNC_HW_IN_FLOW;
4718 		DEBUGCONT2(ASY_DEBUG_HFLOW, "async%d: input hflow stop, "
4719 		    "type = %x\n", instance, async->async_inflow_source);
4720 		break;
4721 	case FLOW_START:
4722 		async->async_inflow_source &= ~type;
4723 		if (async->async_inflow_source == 0) {
4724 			async->async_flags &= ~ASYNC_HW_IN_FLOW;
4725 			DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: "
4726 			    "input hflow start\n", instance);
4727 		}
4728 		break;
4729 	default:
4730 		break;
4731 	}
4732 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4733 	flag = (async->async_flags & ASYNC_HW_IN_FLOW) ? 0 : RTS;
4734 
4735 	if (((mcr ^ flag) & RTS) != 0) {
4736 		ddi_put8(asy->asy_iohandle,
4737 		    asy->asy_ioaddr + MCR, (mcr ^ RTS));
4738 	}
4739 }
4740 
4741 /*
4742  * Hardware output flow control
4743  * This function can execute HW output flow control sucessfully
4744  * at any situation.
4745  * It doesn't really change RTS, and just change
4746  * HW output flow control flag depending on CTS status.
4747  * INPUT VALUE of onoff:
4748  *                FLOW_START means to clear HW output flow control flag.
4749  *			also combine with SW output flow control status to
4750  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4751  *                FLOW_STOP means to set HW output flow control flag.
4752  *			also clear ASYNC_OUT_FLW_RESUME.
4753  */
4754 static void
4755 async_flowcontrol_hw_output(struct asycom *asy, async_flowc_action onoff)
4756 {
4757 	struct asyncline *async = asy->asy_priv;
4758 	int instance = UNIT(async->async_dev);
4759 
4760 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4761 
4762 	if (!(async->async_ttycommon.t_cflag & CRTSCTS))
4763 		return;
4764 
4765 	switch (onoff) {
4766 	case FLOW_STOP:
4767 		async->async_flags |= ASYNC_HW_OUT_FLW;
4768 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4769 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow stop\n",
4770 		    instance);
4771 		break;
4772 	case FLOW_START:
4773 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
4774 		if (!(async->async_flags & ASYNC_SW_OUT_FLW))
4775 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4776 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow start\n",
4777 		    instance);
4778 		break;
4779 	default:
4780 		break;
4781 	}
4782 }
4783 
4784 
4785 /*
4786  * quiesce(9E) entry point.
4787  *
4788  * This function is called when the system is single-threaded at high
4789  * PIL with preemption disabled. Therefore, this function must not be
4790  * blocked.
4791  *
4792  * This function returns DDI_SUCCESS on success, or DDI_FAILURE on failure.
4793  * DDI_FAILURE indicates an error condition and should almost never happen.
4794  */
4795 static int
4796 asyquiesce(dev_info_t *devi)
4797 {
4798 	int instance;
4799 	struct asycom *asy;
4800 
4801 	instance = ddi_get_instance(devi);	/* find out which unit */
4802 
4803 	asy = ddi_get_soft_state(asy_soft_state, instance);
4804 	if (asy == NULL)
4805 		return (DDI_FAILURE);
4806 
4807 	/* disable all interrupts */
4808 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
4809 
4810 	/* reset the FIFO */
4811 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
4812 
4813 	return (DDI_SUCCESS);
4814 }
4815