xref: /netbsd-src/sys/dev/usb/ucom.c (revision 151a4210f9186c5e093d6b0fbcdf398cea0c7f9a)
1 /*	$NetBSD: ucom.c,v 1.139 2024/04/12 16:54:37 jakllsch Exp $	*/
2 
3 /*
4  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Lennart Augustsson (lennart@augustsson.net) at
9  * Carlstedt Research & Technology.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 /*
33  * This code is very heavily based on the 16550 driver, com.c.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: ucom.c,v 1.139 2024/04/12 16:54:37 jakllsch Exp $");
38 
39 #ifdef _KERNEL_OPT
40 #include "opt_ntp.h"
41 #include "opt_usb.h"
42 #endif
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/ioctl.h>
48 #include <sys/conf.h>
49 #include <sys/tty.h>
50 #include <sys/file.h>
51 #include <sys/select.h>
52 #include <sys/proc.h>
53 #include <sys/vnode.h>
54 #include <sys/device.h>
55 #include <sys/poll.h>
56 #include <sys/queue.h>
57 #include <sys/kauth.h>
58 #include <sys/sysctl.h>
59 #include <sys/timepps.h>
60 #include <sys/rndsource.h>
61 
62 #include <dev/usb/usb.h>
63 
64 #include <dev/usb/usbdi.h>
65 #include <dev/usb/usbdi_util.h>
66 #include <dev/usb/usbdevs.h>
67 #include <dev/usb/usb_quirks.h>
68 #include <dev/usb/usbhist.h>
69 
70 #include <dev/usb/ucomvar.h>
71 
72 #include "ucom.h"
73 #include "locators.h"
74 #include "ioconf.h"
75 
76 #if NUCOM > 0
77 
78 #ifdef USB_DEBUG
79 #ifndef UCOM_DEBUG
80 #define ucomdebug 0
81 #else
82 int ucomdebug = 0;
83 
84 SYSCTL_SETUP(sysctl_hw_ucom_setup, "sysctl hw.ucom setup")
85 {
86 	int err;
87 	const struct sysctlnode *rnode;
88 	const struct sysctlnode *cnode;
89 
90 	err = sysctl_createv(clog, 0, NULL, &rnode,
91 	    CTLFLAG_PERMANENT, CTLTYPE_NODE, "ucom",
92 	    SYSCTL_DESCR("ucom global controls"),
93 	    NULL, 0, NULL, 0, CTL_HW, CTL_CREATE, CTL_EOL);
94 
95 	if (err)
96 		goto fail;
97 
98 	/* control debugging printfs */
99 	err = sysctl_createv(clog, 0, &rnode, &cnode,
100 	    CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT,
101 	    "debug", SYSCTL_DESCR("Enable debugging output"),
102 	    NULL, 0, &ucomdebug, sizeof(ucomdebug), CTL_CREATE, CTL_EOL);
103 	if (err)
104 		goto fail;
105 
106 	return;
107 fail:
108 	aprint_error("%s: sysctl_createv failed (err = %d)\n", __func__, err);
109 }
110 
111 #endif /* UCOM_DEBUG */
112 #endif /* USB_DEBUG */
113 
114 #define DPRINTF(FMT,A,B,C,D)    USBHIST_LOGN(ucomdebug,1,FMT,A,B,C,D)
115 #define DPRINTFN(N,FMT,A,B,C,D) USBHIST_LOGN(ucomdebug,N,FMT,A,B,C,D)
116 #define UCOMHIST_FUNC()         USBHIST_FUNC()
117 #define UCOMHIST_CALLED(name)   USBHIST_CALLED(ucomdebug)
118 
119 #define	UCOMCALLUNIT_MASK	TTCALLUNIT_MASK
120 #define	UCOMUNIT_MASK		TTUNIT_MASK
121 #define	UCOMDIALOUT_MASK	TTDIALOUT_MASK
122 
123 #define	UCOMCALLUNIT(x)		TTCALLUNIT(x)
124 #define	UCOMUNIT(x)		TTUNIT(x)
125 #define	UCOMDIALOUT(x)		TTDIALOUT(x)
126 #define	ucom_unit		tty_unit
127 
128 /*
129  * XXX: We can submit multiple input/output buffers to the usb stack
130  * to improve throughput, but the usb stack is too lame to deal with this
131  * in a number of places.
132  */
133 #define	UCOM_IN_BUFFS	1
134 #define	UCOM_OUT_BUFFS	1
135 
136 struct ucom_buffer {
137 	SIMPLEQ_ENTRY(ucom_buffer) ub_link;
138 	struct usbd_xfer *ub_xfer;
139 	u_char *ub_data;
140 	u_int ub_len;
141 	u_int ub_index;
142 };
143 
144 struct ucom_softc {
145 	device_t		sc_dev;		/* base device */
146 
147 	struct usbd_device *	sc_udev;	/* USB device */
148 	struct usbd_interface *	sc_iface;	/* data interface */
149 
150 	int			sc_bulkin_no;	/* bulk in endpoint address */
151 	struct usbd_pipe *	sc_bulkin_pipe;/* bulk in pipe */
152 	u_int			sc_ibufsize;	/* read buffer size */
153 	u_int			sc_ibufsizepad;	/* read buffer size padded */
154 	struct ucom_buffer	sc_ibuff[UCOM_IN_BUFFS];
155 	SIMPLEQ_HEAD(, ucom_buffer) sc_ibuff_empty;
156 	SIMPLEQ_HEAD(, ucom_buffer) sc_ibuff_full;
157 
158 	int			sc_bulkout_no;	/* bulk out endpoint address */
159 	struct usbd_pipe *	sc_bulkout_pipe;/* bulk out pipe */
160 	u_int			sc_obufsize;	/* write buffer size */
161 	u_int			sc_opkthdrlen;	/* header length of */
162 	struct ucom_buffer	sc_obuff[UCOM_OUT_BUFFS];
163 	SIMPLEQ_HEAD(, ucom_buffer) sc_obuff_free;
164 	SIMPLEQ_HEAD(, ucom_buffer) sc_obuff_full;
165 
166 	void			*sc_si;
167 
168 	const struct ucom_methods *sc_methods;
169 	void                    *sc_parent;
170 	int			sc_portno;
171 
172 	struct tty		*sc_tty;	/* our tty */
173 	u_char			sc_lsr;
174 	u_char			sc_msr;
175 	u_char			sc_mcr;
176 	volatile u_char		sc_rx_stopped;
177 	u_char			sc_rx_unblock;
178 	u_char			sc_tx_stopped;
179 	int			sc_swflags;
180 
181 	enum ucom_state {
182 	    UCOM_DEAD,
183 	    UCOM_ATTACHED,
184 	    UCOM_OPENING,
185 	    UCOM_OPEN
186 	}			sc_state;
187 	bool			sc_closing;	/* software is closing */
188 	bool			sc_dying;	/* hardware is gone */
189 
190 	struct pps_state	sc_pps_state;	/* pps state */
191 
192 	krndsource_t		sc_rndsource;	/* random source */
193 
194 	kmutex_t		sc_lock;
195 	kcondvar_t		sc_statecv;
196 
197 	struct timeval		sc_hup_time;
198 };
199 
200 dev_type_open(ucomopen);
201 dev_type_cancel(ucomcancel);
202 dev_type_close(ucomclose);
203 dev_type_read(ucomread);
204 dev_type_write(ucomwrite);
205 dev_type_ioctl(ucomioctl);
206 dev_type_stop(ucomstop);
207 dev_type_tty(ucomtty);
208 dev_type_poll(ucompoll);
209 
210 const struct cdevsw ucom_cdevsw = {
211 	.d_open = ucomopen,
212 	.d_cancel = ucomcancel,
213 	.d_close = ucomclose,
214 	.d_read = ucomread,
215 	.d_write = ucomwrite,
216 	.d_ioctl = ucomioctl,
217 	.d_stop = ucomstop,
218 	.d_tty = ucomtty,
219 	.d_poll = ucompoll,
220 	.d_mmap = nommap,
221 	.d_kqfilter = ttykqfilter,
222 	.d_discard = nodiscard,
223 	.d_cfdriver = &ucom_cd,
224 	.d_devtounit = ucom_unit,
225 	.d_flag = D_TTY | D_MPSAFE
226 };
227 
228 static void	ucom_cleanup(struct ucom_softc *, int);
229 static int	ucomparam(struct tty *, struct termios *);
230 static int	ucomhwiflow(struct tty *, int);
231 static void	ucomstart(struct tty *);
232 static void	ucom_shutdown(struct ucom_softc *);
233 static void	ucom_dtr(struct ucom_softc *, int);
234 static void	ucom_rts(struct ucom_softc *, int);
235 static void	ucom_break(struct ucom_softc *, int);
236 static void	tiocm_to_ucom(struct ucom_softc *, u_long, int);
237 static int	ucom_to_tiocm(struct ucom_softc *);
238 
239 static void	ucomreadcb(struct usbd_xfer *, void *, usbd_status);
240 static void	ucom_submit_write(struct ucom_softc *, struct ucom_buffer *);
241 static void	ucom_write_status(struct ucom_softc *, struct ucom_buffer *,
242 		    usbd_status);
243 
244 static void	ucomwritecb(struct usbd_xfer *, void *, usbd_status);
245 static void	ucom_read_complete(struct ucom_softc *);
246 static int	ucomsubmitread(struct ucom_softc *, struct ucom_buffer *);
247 static void	ucom_softintr(void *);
248 
249 int ucom_match(device_t, cfdata_t, void *);
250 void ucom_attach(device_t, device_t, void *);
251 int ucom_detach(device_t, int);
252 
253 CFATTACH_DECL_NEW(ucom, sizeof(struct ucom_softc), ucom_match, ucom_attach,
254     ucom_detach, NULL);
255 
256 int
ucom_match(device_t parent,cfdata_t match,void * aux)257 ucom_match(device_t parent, cfdata_t match, void *aux)
258 {
259 	return 1;
260 }
261 
262 void
ucom_attach(device_t parent,device_t self,void * aux)263 ucom_attach(device_t parent, device_t self, void *aux)
264 {
265 	struct ucom_softc *sc = device_private(self);
266 	struct ucom_attach_args *ucaa = aux;
267 
268 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
269 
270 	if (ucaa->ucaa_info != NULL)
271 		aprint_normal(": %s", ucaa->ucaa_info);
272 	aprint_normal("\n");
273 
274 	prop_dictionary_set_int32(device_properties(self), "port",
275 	    ucaa->ucaa_portno);
276 
277 	sc->sc_dev = self;
278 	sc->sc_udev = ucaa->ucaa_device;
279 	sc->sc_iface = ucaa->ucaa_iface;
280 	sc->sc_bulkout_no = ucaa->ucaa_bulkout;
281 	sc->sc_bulkin_no = ucaa->ucaa_bulkin;
282 	sc->sc_ibufsize = ucaa->ucaa_ibufsize;
283 	sc->sc_ibufsizepad = ucaa->ucaa_ibufsizepad;
284 	sc->sc_obufsize = ucaa->ucaa_obufsize;
285 	sc->sc_opkthdrlen = ucaa->ucaa_opkthdrlen;
286 	sc->sc_methods = ucaa->ucaa_methods;
287 	sc->sc_parent = ucaa->ucaa_arg;
288 	sc->sc_portno = ucaa->ucaa_portno;
289 
290 	sc->sc_lsr = 0;
291 	sc->sc_msr = 0;
292 	sc->sc_mcr = 0;
293 	sc->sc_tx_stopped = 0;
294 	sc->sc_swflags = 0;
295 	sc->sc_closing = false;
296 	sc->sc_dying = false;
297 	sc->sc_state = UCOM_DEAD;
298 
299 	sc->sc_si = softint_establish(SOFTINT_USB, ucom_softintr, sc);
300 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_SOFTUSB);
301 	cv_init(&sc->sc_statecv, "ucomstate");
302 
303 	rnd_attach_source(&sc->sc_rndsource, device_xname(sc->sc_dev),
304 	    RND_TYPE_TTY, RND_FLAG_DEFAULT);
305 
306 	SIMPLEQ_INIT(&sc->sc_ibuff_empty);
307 	SIMPLEQ_INIT(&sc->sc_ibuff_full);
308 	SIMPLEQ_INIT(&sc->sc_obuff_free);
309 	SIMPLEQ_INIT(&sc->sc_obuff_full);
310 
311 	memset(sc->sc_ibuff, 0, sizeof(sc->sc_ibuff));
312 	memset(sc->sc_obuff, 0, sizeof(sc->sc_obuff));
313 
314 	DPRINTF("open pipes in=%jd out=%jd",
315 	    sc->sc_bulkin_no, sc->sc_bulkout_no, 0, 0);
316 
317 	struct ucom_buffer *ub;
318 	usbd_status err;
319 	int error;
320 
321 	/* Open the bulk pipes */
322 	err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkin_no,
323 	    USBD_EXCLUSIVE_USE, &sc->sc_bulkin_pipe);
324 	if (err) {
325 		DPRINTF("open bulk in error (addr %jd), err=%jd",
326 		    sc->sc_bulkin_no, err, 0, 0);
327 		error = EIO;
328 		goto fail_0;
329 	}
330 	/* Allocate input buffers */
331 	for (ub = &sc->sc_ibuff[0]; ub != &sc->sc_ibuff[UCOM_IN_BUFFS];
332 	    ub++) {
333 		error = usbd_create_xfer(sc->sc_bulkin_pipe,
334 		    sc->sc_ibufsizepad, 0, 0,
335 		    &ub->ub_xfer);
336 		if (error)
337 			goto fail_1;
338 		ub->ub_data = usbd_get_buffer(ub->ub_xfer);
339 	}
340 
341 	err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkout_no,
342 	    USBD_EXCLUSIVE_USE, &sc->sc_bulkout_pipe);
343 	if (err) {
344 		DPRINTF("open bulk out error (addr %jd), err=%jd",
345 		    sc->sc_bulkout_no, err, 0, 0);
346 		error = EIO;
347 		goto fail_1;
348 	}
349 	for (ub = &sc->sc_obuff[0]; ub != &sc->sc_obuff[UCOM_OUT_BUFFS];
350 	    ub++) {
351 		error = usbd_create_xfer(sc->sc_bulkout_pipe,
352 		    sc->sc_obufsize, 0, 0, &ub->ub_xfer);
353 		if (error)
354 			goto fail_2;
355 		ub->ub_data = usbd_get_buffer(ub->ub_xfer);
356 		SIMPLEQ_INSERT_TAIL(&sc->sc_obuff_free, ub, ub_link);
357 	}
358 
359 	struct tty *tp = tty_alloc();
360 	tp->t_oproc = ucomstart;
361 	tp->t_param = ucomparam;
362 	tp->t_hwiflow = ucomhwiflow;
363 	sc->sc_tty = tp;
364 
365 	DPRINTF("tty_attach %#jx", (uintptr_t)tp, 0, 0, 0);
366 	tty_attach(tp);
367 
368 	if (!pmf_device_register(self, NULL, NULL))
369 		aprint_error_dev(self, "couldn't establish power handler\n");
370 
371 	sc->sc_state = UCOM_ATTACHED;
372 	return;
373 
374 fail_2:
375 	for (ub = &sc->sc_obuff[0]; ub != &sc->sc_obuff[UCOM_OUT_BUFFS];
376 	    ub++) {
377 		if (ub->ub_xfer)
378 			usbd_destroy_xfer(ub->ub_xfer);
379 	}
380 	usbd_close_pipe(sc->sc_bulkout_pipe);
381 	sc->sc_bulkout_pipe = NULL;
382 
383 fail_1:
384 	for (ub = &sc->sc_ibuff[0]; ub != &sc->sc_ibuff[UCOM_IN_BUFFS];
385 	    ub++) {
386 		if (ub->ub_xfer)
387 			usbd_destroy_xfer(ub->ub_xfer);
388 	}
389 	usbd_close_pipe(sc->sc_bulkin_pipe);
390 	sc->sc_bulkin_pipe = NULL;
391 
392 fail_0:
393 	aprint_error_dev(self, "attach failed, error=%d\n", error);
394 }
395 
396 int
ucom_detach(device_t self,int flags)397 ucom_detach(device_t self, int flags)
398 {
399 	struct ucom_softc *sc = device_private(self);
400 	struct tty *tp = sc->sc_tty;
401 	int maj, mn;
402 	int i;
403 
404 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
405 
406 	DPRINTF("sc=%#jx flags=%jd tp=%#jx", (uintptr_t)sc, flags,
407 	    (uintptr_t)tp, 0);
408 	DPRINTF("... pipe=%jd,%jd", sc->sc_bulkin_no, sc->sc_bulkout_no, 0, 0);
409 
410 	/* Prevent new opens from hanging.  */
411 	mutex_enter(&sc->sc_lock);
412 	sc->sc_dying = true;
413 	mutex_exit(&sc->sc_lock);
414 
415 	pmf_device_deregister(self);
416 
417 	/* tty is now off.  */
418 	if (tp != NULL) {
419 		ttylock(tp);
420 		CLR(tp->t_state, TS_CARR_ON);
421 		CLR(tp->t_cflag, CLOCAL | MDMBUF);
422 		ttyunlock(tp);
423 	}
424 
425 	/* locate the major number */
426 	maj = cdevsw_lookup_major(&ucom_cdevsw);
427 
428 	/* Nuke the vnodes for any open instances. */
429 	mn = device_unit(self);
430 	DPRINTF("maj=%jd mn=%jd", maj, mn, 0, 0);
431 	vdevgone(maj, mn, mn, VCHR);
432 	vdevgone(maj, mn | UCOMDIALOUT_MASK, mn | UCOMDIALOUT_MASK, VCHR);
433 	vdevgone(maj, mn | UCOMCALLUNIT_MASK, mn | UCOMCALLUNIT_MASK, VCHR);
434 
435 	softint_disestablish(sc->sc_si);
436 
437 	/* Detach and free the tty. */
438 	if (tp != NULL) {
439 		tty_detach(tp);
440 		tty_free(tp);
441 		sc->sc_tty = NULL;
442 	}
443 
444 	for (i = 0; i < UCOM_IN_BUFFS; i++) {
445 		if (sc->sc_ibuff[i].ub_xfer != NULL)
446 			usbd_destroy_xfer(sc->sc_ibuff[i].ub_xfer);
447 	}
448 
449 	for (i = 0; i < UCOM_OUT_BUFFS; i++) {
450 		if (sc->sc_obuff[i].ub_xfer != NULL)
451 			usbd_destroy_xfer(sc->sc_obuff[i].ub_xfer);
452 	}
453 
454 	if (sc->sc_bulkin_pipe != NULL) {
455 		usbd_close_pipe(sc->sc_bulkin_pipe);
456 		sc->sc_bulkin_pipe = NULL;
457 	}
458 
459 	if (sc->sc_bulkout_pipe != NULL) {
460 		usbd_close_pipe(sc->sc_bulkout_pipe);
461 		sc->sc_bulkout_pipe = NULL;
462 	}
463 
464 	/* Detach the random source */
465 	rnd_detach_source(&sc->sc_rndsource);
466 
467 	mutex_destroy(&sc->sc_lock);
468 	cv_destroy(&sc->sc_statecv);
469 
470 	return 0;
471 }
472 
473 void
ucom_shutdown(struct ucom_softc * sc)474 ucom_shutdown(struct ucom_softc *sc)
475 {
476 	struct tty *tp = sc->sc_tty;
477 
478 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
479 
480 	/*
481 	 * Hang up if necessary.  Wait a bit, so the other side has time to
482 	 * notice even if we immediately open the port again.
483 	 */
484 	if (ISSET(tp->t_cflag, HUPCL)) {
485 		ucom_dtr(sc, 0);
486 		mutex_enter(&sc->sc_lock);
487 		microuptime(&sc->sc_hup_time);
488 		sc->sc_hup_time.tv_sec++;
489 		mutex_exit(&sc->sc_lock);
490 	}
491 }
492 
493 /*
494  * ucomopen(dev, flag, mode, l)
495  *
496  *	Called when anyone tries to open /dev/ttyU? for an existing
497  *	ucom? instance that has completed attach.  The attach may have
498  *	failed, though, or there may be concurrent detach or close in
499  *	progress, so fail if attach failed (no sc_tty) or detach has
500  *	begun (sc_dying), or wait if there's a concurrent close in
501  *	progress before reopening.
502  */
503 int
ucomopen(dev_t dev,int flag,int mode,struct lwp * l)504 ucomopen(dev_t dev, int flag, int mode, struct lwp *l)
505 {
506 	const int unit = UCOMUNIT(dev);
507 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
508 	int error = 0;
509 
510 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
511 
512 	mutex_enter(&sc->sc_lock);
513 	if (sc->sc_dying) {
514 		DPRINTF("... dying", 0, 0, 0, 0);
515 		mutex_exit(&sc->sc_lock);
516 		return ENXIO;
517 	}
518 
519 	if (!device_is_active(sc->sc_dev)) {
520 		mutex_exit(&sc->sc_lock);
521 		return ENXIO;
522 	}
523 
524 	struct tty *tp = sc->sc_tty;
525 	if (tp == NULL) {
526 		DPRINTF("... not attached", 0, 0, 0, 0);
527 		mutex_exit(&sc->sc_lock);
528 		return ENXIO;
529 	}
530 
531 	DPRINTF("unit=%jd, tp=%#jx", unit, (uintptr_t)tp, 0, 0);
532 
533 	if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp)) {
534 		mutex_exit(&sc->sc_lock);
535 		return EBUSY;
536 	}
537 
538 	/*
539 	 * If the previous use had set DTR on close, wait up to one
540 	 * second for the other side to notice we hung up.  After
541 	 * sleeping, the tty may have been revoked, so restart the
542 	 * whole operation.
543 	 *
544 	 * XXX The wchan is not ttclose but maybe should be.
545 	 */
546 	if (timerisset(&sc->sc_hup_time)) {
547 		struct timeval now, delta;
548 		int ms, ticks;
549 
550 		microuptime(&now);
551 		if (timercmp(&now, &sc->sc_hup_time, <)) {
552 			timersub(&sc->sc_hup_time, &now, &delta);
553 			ms = MIN(INT_MAX - 1000, delta.tv_sec*1000);
554 			ms += howmany(delta.tv_usec, 1000);
555 			ticks = MAX(1, MIN(INT_MAX, mstohz(ms)));
556 			(void)cv_timedwait(&sc->sc_statecv, &sc->sc_lock,
557 			    ticks);
558 			mutex_exit(&sc->sc_lock);
559 			return ERESTART;
560 		}
561 		timerclear(&sc->sc_hup_time);
562 	}
563 
564 	/*
565 	 * Wait while the device is initialized by the
566 	 * first opener or cleaned up by the last closer.
567 	 */
568 	enum ucom_state state = sc->sc_state;
569 	if (state == UCOM_OPENING || sc->sc_closing) {
570 		if (flag & FNONBLOCK)
571 			error = EWOULDBLOCK;
572 		else
573 			error = cv_wait_sig(&sc->sc_statecv, &sc->sc_lock);
574 		mutex_exit(&sc->sc_lock);
575 		return error ? error : ERESTART;
576 	}
577 	KASSERTMSG(state == UCOM_OPEN || state == UCOM_ATTACHED,
578 	    "state is %d", state);
579 
580 	/*
581 	 * If this is the first open, then make sure the pipes are
582 	 * running and perform any initialization needed.
583 	 */
584 	bool firstopen = (state == UCOM_ATTACHED);
585 	if (firstopen) {
586 		KASSERT(!ISSET(tp->t_state, TS_ISOPEN));
587 		KASSERT(tp->t_wopen == 0);
588 
589 		tp->t_dev = dev;
590 		sc->sc_state = UCOM_OPENING;
591 		mutex_exit(&sc->sc_lock);
592 
593 		if (sc->sc_methods->ucom_open != NULL) {
594 			error = sc->sc_methods->ucom_open(sc->sc_parent,
595 			    sc->sc_portno);
596 			if (error)
597 				goto bad;
598 		}
599 
600 		ucom_status_change(sc);
601 
602 		/* Clear PPS capture state on first open. */
603 		mutex_spin_enter(&timecounter_lock);
604 		memset(&sc->sc_pps_state, 0, sizeof(sc->sc_pps_state));
605 		sc->sc_pps_state.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
606 		pps_init(&sc->sc_pps_state);
607 		mutex_spin_exit(&timecounter_lock);
608 
609 		/*
610 		 * Initialize the termios status to the defaults.  Add in the
611 		 * sticky bits from TIOCSFLAGS.
612 		 */
613 		struct termios t;
614 
615 		t.c_ispeed = 0;
616 		t.c_ospeed = TTYDEF_SPEED;
617 		t.c_cflag = TTYDEF_CFLAG;
618 		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
619 			SET(t.c_cflag, CLOCAL);
620 		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
621 			SET(t.c_cflag, CRTSCTS);
622 		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
623 			SET(t.c_cflag, MDMBUF);
624 		/* Make sure ucomparam() will do something. */
625 		tp->t_ospeed = 0;
626 		(void) ucomparam(tp, &t);
627 		tp->t_iflag = TTYDEF_IFLAG;
628 		tp->t_oflag = TTYDEF_OFLAG;
629 		tp->t_lflag = TTYDEF_LFLAG;
630 		ttychars(tp);
631 		ttsetwater(tp);
632 
633 		/*
634 		 * Turn on DTR.  We must always do this, even if carrier is not
635 		 * present, because otherwise we'd have to use TIOCSDTR
636 		 * immediately after setting CLOCAL, which applications do not
637 		 * expect.  We always assert DTR while the device is open
638 		 * unless explicitly requested to deassert it.  Ditto RTS.
639 		 */
640 		ucom_dtr(sc, 1);
641 		ucom_rts(sc, 1);
642 
643 		mutex_enter(&sc->sc_lock);
644 		sc->sc_rx_unblock = 0;
645 		sc->sc_rx_stopped = 0;
646 		sc->sc_tx_stopped = 0;
647 
648 		for (size_t i = 0; i < UCOM_IN_BUFFS; i++) {
649 			struct ucom_buffer *ub = &sc->sc_ibuff[i];
650 			error = ucomsubmitread(sc, ub);
651 			if (error) {
652 		    		mutex_exit(&sc->sc_lock);
653 				goto bad;
654 			}
655 		}
656 	}
657 	mutex_exit(&sc->sc_lock);
658 
659 	DPRINTF("unit=%jd, tp=%#jx dialout %jd nonblock %jd", unit,
660 	    (uintptr_t)tp, !!UCOMDIALOUT(dev), !!ISSET(flag, O_NONBLOCK));
661 	error = ttyopen(tp, UCOMDIALOUT(dev), ISSET(flag, O_NONBLOCK));
662 	if (error)
663 		goto bad;
664 
665 	error = (*tp->t_linesw->l_open)(dev, tp);
666 	if (error)
667 		goto bad;
668 
669 	/*
670 	 * Success!  If this was the first open, notify waiters that
671 	 * the tty is open for business.
672 	 */
673 	if (firstopen) {
674 		mutex_enter(&sc->sc_lock);
675 		KASSERT(sc->sc_state == UCOM_OPENING);
676 		sc->sc_state = UCOM_OPEN;
677 		cv_broadcast(&sc->sc_statecv);
678 		mutex_exit(&sc->sc_lock);
679 	}
680 	return 0;
681 
682 bad:
683 	/*
684 	 * Failure!  If this was the first open, hang up, abort pipes,
685 	 * and notify waiters that we're not opening after all.
686 	 */
687 	if (firstopen) {
688 		ucom_cleanup(sc, flag);
689 
690 		mutex_enter(&sc->sc_lock);
691 		KASSERT(sc->sc_state == UCOM_OPENING);
692 		sc->sc_state = UCOM_ATTACHED;
693 		cv_broadcast(&sc->sc_statecv);
694 		mutex_exit(&sc->sc_lock);
695 	}
696 	return error;
697 }
698 
699 /*
700  * ucomcancel(dev, flag, mode, l)
701  *
702  *	Called on revoke or last close.  Must interrupt any pending I/O
703  *	operations and make them fail promptly; once they have all
704  *	finished (except possibly new opens), ucomclose will be called.
705  *	We set sc_closing to block new opens until ucomclose runs.
706  */
707 int
ucomcancel(dev_t dev,int flag,int mode,struct lwp * l)708 ucomcancel(dev_t dev, int flag, int mode, struct lwp *l)
709 {
710 	const int unit = UCOMUNIT(dev);
711 	struct ucom_softc *sc = device_lookup_private(&ucom_cd, unit);
712 
713 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
714 
715 	DPRINTF("unit=%jd", UCOMUNIT(dev), 0, 0, 0);
716 
717 	/*
718 	 * This can run at any time before ucomclose on any device
719 	 * node, even if never attached or if attach failed, so we may
720 	 * not have a softc or a tty.
721 	 */
722 	if (sc == NULL)
723 		return 0;
724 	struct tty *tp = sc->sc_tty;
725 	if (tp == NULL)
726 		return 0;
727 
728 	/*
729 	 * Mark the device closing so opens block until we're done
730 	 * closing.  Wake them up so they start over at the top -- if
731 	 * we're closing because we're detaching, they need to wake up
732 	 * and notice it's time to fail.
733 	 */
734 	mutex_enter(&sc->sc_lock);
735 	sc->sc_closing = true;
736 	cv_broadcast(&sc->sc_statecv);
737 	mutex_exit(&sc->sc_lock);
738 
739 	/*
740 	 * Cancel any pending tty I/O operations, causing them to wake
741 	 * up and fail promptly, and preventing any new ones from
742 	 * starting to wait until we have finished closing.
743 	 */
744 	ttycancel(tp);
745 
746 	return 0;
747 }
748 
749 /*
750  * ucomclose(dev, flag, mode, l)
751  *
752  *	Called after ucomcancel, when all prior operations on the /dev
753  *	node have completed.  Only new opens may be in progress at this
754  *	point, but they will block until sc_closing is set to false.
755  */
756 int
ucomclose(dev_t dev,int flag,int mode,struct lwp * l)757 ucomclose(dev_t dev, int flag, int mode, struct lwp *l)
758 {
759 	const int unit = UCOMUNIT(dev);
760 	struct ucom_softc *sc = device_lookup_private(&ucom_cd, unit);
761 	int error = 0;
762 
763 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
764 
765 	DPRINTF("unit=%jd", UCOMUNIT(dev), 0, 0, 0);
766 
767 	/*
768 	 * This can run at any time after ucomcancel on any device
769 	 * node, even if never attached or if attach failed, so we may
770 	 * not have a softc or a tty.
771 	 */
772 	if (sc == NULL)
773 		return 0;
774 	struct tty *tp = sc->sc_tty;
775 	if (tp == NULL)
776 		return 0;
777 
778 	/*
779 	 * Close the tty, causing anyone waiting for it to wake, and
780 	 * hang up the phone.
781 	 */
782 	ucom_cleanup(sc, flag);
783 
784 	/*
785 	 * ttyclose should have cleared TS_ISOPEN and interrupted all
786 	 * pending opens, which should have completed by now.
787 	 */
788 	ttylock(tp);
789 	KASSERT(!ISSET(tp->t_state, TS_ISOPEN));
790 	KASSERT(tp->t_wopen == 0);
791 	ttyunlock(tp);
792 
793 	/*
794 	 * Close any device-specific state.
795 	 */
796 	if (sc->sc_methods->ucom_close != NULL) {
797 		sc->sc_methods->ucom_close(sc->sc_parent,
798 		    sc->sc_portno);
799 	}
800 
801 	/*
802 	 * We're now closed.  Can reopen after this point, so resume
803 	 * transfers, mark us no longer closing, and notify anyone
804 	 * waiting in open.  The state may be OPEN or ATTACHED at this
805 	 * point -- OPEN if the device was already open when we closed
806 	 * it, ATTACHED if we interrupted it in the process of opening.
807 	 */
808 	mutex_enter(&sc->sc_lock);
809 	KASSERTMSG(sc->sc_state == UCOM_ATTACHED || sc->sc_state == UCOM_OPEN,
810 	    "%s sc=%p state=%d", device_xname(sc->sc_dev), sc, sc->sc_state);
811 	KASSERT(sc->sc_closing);
812 	sc->sc_state = UCOM_ATTACHED;
813 	sc->sc_closing = false;
814 	cv_broadcast(&sc->sc_statecv);
815 	mutex_exit(&sc->sc_lock);
816 
817 	return error;
818 }
819 
820 int
ucomread(dev_t dev,struct uio * uio,int flag)821 ucomread(dev_t dev, struct uio *uio, int flag)
822 {
823 	const int unit = UCOMUNIT(dev);
824 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
825 	struct tty *tp = sc->sc_tty;
826 
827 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
828 
829 	return (*tp->t_linesw->l_read)(tp, uio, flag);
830 }
831 
832 int
ucomwrite(dev_t dev,struct uio * uio,int flag)833 ucomwrite(dev_t dev, struct uio *uio, int flag)
834 {
835 	const int unit = UCOMUNIT(dev);
836 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
837 	struct tty *tp = sc->sc_tty;
838 
839 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
840 
841 	return (*tp->t_linesw->l_write)(tp, uio, flag);
842 }
843 
844 int
ucompoll(dev_t dev,int events,struct lwp * l)845 ucompoll(dev_t dev, int events, struct lwp *l)
846 {
847 	const int unit = UCOMUNIT(dev);
848 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
849 	struct tty *tp = sc->sc_tty;
850 
851 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
852 
853 	return (*tp->t_linesw->l_poll)(tp, events, l);
854 }
855 
856 struct tty *
ucomtty(dev_t dev)857 ucomtty(dev_t dev)
858 {
859 	const int unit = UCOMUNIT(dev);
860 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
861 
862 	return sc->sc_tty;
863 }
864 
865 int
ucomioctl(dev_t dev,u_long cmd,void * data,int flag,struct lwp * l)866 ucomioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
867 {
868 	const int unit = UCOMUNIT(dev);
869 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
870 	struct tty *tp = sc->sc_tty;
871 	int error;
872 
873 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
874 
875 	DPRINTF("cmd=0x%08jx", cmd, 0, 0, 0);
876 
877 	error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
878 	if (error != EPASSTHROUGH)
879 		return error;
880 
881 	error = ttioctl(tp, cmd, data, flag, l);
882 	if (error != EPASSTHROUGH)
883 		return error;
884 
885 	if (sc->sc_methods->ucom_ioctl != NULL) {
886 		error = sc->sc_methods->ucom_ioctl(sc->sc_parent,
887 		    sc->sc_portno, cmd, data, flag, l->l_proc);
888 		if (error != EPASSTHROUGH)
889 			return error;
890 	}
891 
892 	error = 0;
893 
894 	DPRINTF("our cmd=0x%08jx", cmd, 0, 0, 0);
895 
896 	switch (cmd) {
897 	case TIOCSBRK:
898 		ucom_break(sc, 1);
899 		break;
900 
901 	case TIOCCBRK:
902 		ucom_break(sc, 0);
903 		break;
904 
905 	case TIOCSDTR:
906 		ucom_dtr(sc, 1);
907 		break;
908 
909 	case TIOCCDTR:
910 		ucom_dtr(sc, 0);
911 		break;
912 
913 	case TIOCGFLAGS:
914 		mutex_enter(&sc->sc_lock);
915 		*(int *)data = sc->sc_swflags;
916 		mutex_exit(&sc->sc_lock);
917 		break;
918 
919 	case TIOCSFLAGS:
920 		error = kauth_authorize_device_tty(l->l_cred,
921 		    KAUTH_DEVICE_TTY_PRIVSET, tp);
922 		if (error)
923 			break;
924 		mutex_enter(&sc->sc_lock);
925 		sc->sc_swflags = *(int *)data;
926 		mutex_exit(&sc->sc_lock);
927 		break;
928 
929 	case TIOCMSET:
930 	case TIOCMBIS:
931 	case TIOCMBIC:
932 		tiocm_to_ucom(sc, cmd, *(int *)data);
933 		break;
934 
935 	case TIOCMGET:
936 		*(int *)data = ucom_to_tiocm(sc);
937 		break;
938 
939 	case PPS_IOC_CREATE:
940 	case PPS_IOC_DESTROY:
941 	case PPS_IOC_GETPARAMS:
942 	case PPS_IOC_SETPARAMS:
943 	case PPS_IOC_GETCAP:
944 	case PPS_IOC_FETCH:
945 #ifdef PPS_SYNC
946 	case PPS_IOC_KCBIND:
947 #endif
948 		mutex_spin_enter(&timecounter_lock);
949 		error = pps_ioctl(cmd, data, &sc->sc_pps_state);
950 		mutex_spin_exit(&timecounter_lock);
951 		break;
952 
953 	default:
954 		error = EPASSTHROUGH;
955 		break;
956 	}
957 
958 	return error;
959 }
960 
961 static void
tiocm_to_ucom(struct ucom_softc * sc,u_long how,int ttybits)962 tiocm_to_ucom(struct ucom_softc *sc, u_long how, int ttybits)
963 {
964 	u_char combits;
965 
966 	combits = 0;
967 	if (ISSET(ttybits, TIOCM_DTR))
968 		SET(combits, UMCR_DTR);
969 	if (ISSET(ttybits, TIOCM_RTS))
970 		SET(combits, UMCR_RTS);
971 
972 	mutex_enter(&sc->sc_lock);
973 	switch (how) {
974 	case TIOCMBIC:
975 		CLR(sc->sc_mcr, combits);
976 		break;
977 
978 	case TIOCMBIS:
979 		SET(sc->sc_mcr, combits);
980 		break;
981 
982 	case TIOCMSET:
983 		CLR(sc->sc_mcr, UMCR_DTR | UMCR_RTS);
984 		SET(sc->sc_mcr, combits);
985 		break;
986 	}
987 	u_char mcr = sc->sc_mcr;
988 	mutex_exit(&sc->sc_lock);
989 
990 	if (how == TIOCMSET || ISSET(combits, UMCR_DTR))
991 		ucom_dtr(sc, (mcr & UMCR_DTR) != 0);
992 	if (how == TIOCMSET || ISSET(combits, UMCR_RTS))
993 		ucom_rts(sc, (mcr & UMCR_RTS) != 0);
994 }
995 
996 static int
ucom_to_tiocm(struct ucom_softc * sc)997 ucom_to_tiocm(struct ucom_softc *sc)
998 {
999 	u_char combits;
1000 	int ttybits = 0;
1001 
1002 	mutex_enter(&sc->sc_lock);
1003 	combits = sc->sc_mcr;
1004 	if (ISSET(combits, UMCR_DTR))
1005 		SET(ttybits, TIOCM_DTR);
1006 	if (ISSET(combits, UMCR_RTS))
1007 		SET(ttybits, TIOCM_RTS);
1008 
1009 	combits = sc->sc_msr;
1010 	if (ISSET(combits, UMSR_DCD))
1011 		SET(ttybits, TIOCM_CD);
1012 	if (ISSET(combits, UMSR_CTS))
1013 		SET(ttybits, TIOCM_CTS);
1014 	if (ISSET(combits, UMSR_DSR))
1015 		SET(ttybits, TIOCM_DSR);
1016 	if (ISSET(combits, UMSR_RI | UMSR_TERI))
1017 		SET(ttybits, TIOCM_RI);
1018 
1019 #if 0
1020 XXX;
1021 	if (sc->sc_ier != 0)
1022 		SET(ttybits, TIOCM_LE);
1023 #endif
1024 	mutex_exit(&sc->sc_lock);
1025 
1026 	return ttybits;
1027 }
1028 
1029 static void
ucom_break(struct ucom_softc * sc,int onoff)1030 ucom_break(struct ucom_softc *sc, int onoff)
1031 {
1032 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1033 
1034 	DPRINTF("onoff=%jd", onoff, 0, 0, 0);
1035 
1036 	if (sc->sc_methods->ucom_set != NULL)
1037 		sc->sc_methods->ucom_set(sc->sc_parent, sc->sc_portno,
1038 		    UCOM_SET_BREAK, onoff);
1039 }
1040 
1041 static void
ucom_dtr(struct ucom_softc * sc,int onoff)1042 ucom_dtr(struct ucom_softc *sc, int onoff)
1043 {
1044 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1045 
1046 	DPRINTF("onoff=%jd", onoff, 0, 0, 0);
1047 
1048 	if (sc->sc_methods->ucom_set != NULL)
1049 		sc->sc_methods->ucom_set(sc->sc_parent, sc->sc_portno,
1050 		    UCOM_SET_DTR, onoff);
1051 }
1052 
1053 static void
ucom_rts(struct ucom_softc * sc,int onoff)1054 ucom_rts(struct ucom_softc *sc, int onoff)
1055 {
1056 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1057 
1058 	DPRINTF("onoff=%jd", onoff, 0, 0, 0);
1059 
1060 	if (sc->sc_methods->ucom_set != NULL)
1061 		sc->sc_methods->ucom_set(sc->sc_parent, sc->sc_portno,
1062 		    UCOM_SET_RTS, onoff);
1063 }
1064 
1065 void
ucom_status_change(struct ucom_softc * sc)1066 ucom_status_change(struct ucom_softc *sc)
1067 {
1068 	struct tty *tp = sc->sc_tty;
1069 
1070 	if (sc->sc_methods->ucom_get_status != NULL) {
1071 		u_char msr, lsr;
1072 
1073 		sc->sc_methods->ucom_get_status(sc->sc_parent, sc->sc_portno,
1074 		    &lsr, &msr);
1075 		mutex_enter(&sc->sc_lock);
1076 		u_char old_msr = sc->sc_msr;
1077 
1078 		sc->sc_lsr = lsr;
1079 		sc->sc_msr = msr;
1080 		mutex_exit(&sc->sc_lock);
1081 
1082 		if (ISSET((msr ^ old_msr), UMSR_DCD)) {
1083 			mutex_spin_enter(&timecounter_lock);
1084 			pps_capture(&sc->sc_pps_state);
1085 			pps_event(&sc->sc_pps_state,
1086 			    (sc->sc_msr & UMSR_DCD) ?
1087 			    PPS_CAPTUREASSERT :
1088 			    PPS_CAPTURECLEAR);
1089 			mutex_spin_exit(&timecounter_lock);
1090 
1091 			(*tp->t_linesw->l_modem)(tp, ISSET(msr, UMSR_DCD));
1092 		}
1093 	} else {
1094 		mutex_enter(&sc->sc_lock);
1095 		sc->sc_lsr = 0;
1096 		/* Assume DCD is present, if we have no chance to check it. */
1097 		sc->sc_msr = UMSR_DCD;
1098 		mutex_exit(&sc->sc_lock);
1099 	}
1100 }
1101 
1102 static int
ucomparam(struct tty * tp,struct termios * t)1103 ucomparam(struct tty *tp, struct termios *t)
1104 {
1105 	const int unit = UCOMUNIT(tp->t_dev);
1106 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
1107 	int error = 0;
1108 
1109 	/* XXX should take tty lock around touching tp */
1110 
1111 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1112 
1113 	/* Check requested parameters. */
1114 	if (t->c_ispeed && t->c_ispeed != t->c_ospeed) {
1115 		error = EINVAL;
1116 		goto out;
1117 	}
1118 
1119 	/*
1120 	 * For the console, always force CLOCAL and !HUPCL, so that the port
1121 	 * is always active.
1122 	 */
1123 	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR)) {
1124 		SET(t->c_cflag, CLOCAL);
1125 		CLR(t->c_cflag, HUPCL);
1126 	}
1127 
1128 	/*
1129 	 * If there were no changes, don't do anything.  This avoids dropping
1130 	 * input and improves performance when all we did was frob things like
1131 	 * VMIN and VTIME.
1132 	 */
1133 	if (tp->t_ospeed == t->c_ospeed &&
1134 	    tp->t_cflag == t->c_cflag) {
1135 		goto out;
1136 	}
1137 
1138 	/* XXX lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag); */
1139 
1140 	/* And copy to tty. */
1141 	tp->t_ispeed = 0;
1142 	tp->t_ospeed = t->c_ospeed;
1143 	tp->t_cflag = t->c_cflag;
1144 
1145 	if (sc->sc_methods->ucom_param != NULL) {
1146 		error = sc->sc_methods->ucom_param(sc->sc_parent, sc->sc_portno,
1147 		    t);
1148 		if (error)
1149 			goto out;
1150 	}
1151 
1152 	/* XXX worry about CHWFLOW */
1153 
1154 	/*
1155 	 * Update the tty layer's idea of the carrier bit, in case we changed
1156 	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
1157 	 * explicit request.
1158 	 */
1159 	DPRINTF("l_modem", 0, 0, 0, 0);
1160 	(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, UMSR_DCD));
1161 
1162 #if 0
1163 XXX what if the hardware is not open
1164 	if (!ISSET(t->c_cflag, CHWFLOW)) {
1165 		if (sc->sc_tx_stopped) {
1166 			sc->sc_tx_stopped = 0;
1167 			ucomstart(tp);
1168 		}
1169 	}
1170 #endif
1171 out:
1172 	return error;
1173 }
1174 
1175 static int
ucomhwiflow(struct tty * tp,int block)1176 ucomhwiflow(struct tty *tp, int block)
1177 {
1178 	const int unit = UCOMUNIT(tp->t_dev);
1179 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
1180 	int old;
1181 
1182 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1183 
1184 	KASSERT(&sc->sc_lock);
1185 	KASSERT(ttylocked(tp));
1186 
1187 	old = sc->sc_rx_stopped;
1188 	sc->sc_rx_stopped = (u_char)block;
1189 
1190 	if (old && !block) {
1191 		sc->sc_rx_unblock = 1;
1192 		kpreempt_disable();
1193 		softint_schedule(sc->sc_si);
1194 		kpreempt_enable();
1195 	}
1196 
1197 	return 1;
1198 }
1199 
1200 static void
ucomstart(struct tty * tp)1201 ucomstart(struct tty *tp)
1202 {
1203 	const int unit = UCOMUNIT(tp->t_dev);
1204 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
1205 	struct ucom_buffer *ub;
1206 	u_char *data;
1207 	int cnt;
1208 
1209 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1210 
1211 	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
1212 		goto out;
1213 	if (sc->sc_tx_stopped)
1214 		goto out;
1215 
1216 	if (!ttypull(tp))
1217 		goto out;
1218 
1219 	/* Grab the first contiguous region of buffer space. */
1220 	data = tp->t_outq.c_cf;
1221 	cnt = ndqb(&tp->t_outq, 0);
1222 
1223 	if (cnt == 0)
1224 		goto out;
1225 
1226 	ub = SIMPLEQ_FIRST(&sc->sc_obuff_free);
1227 	if (ub == NULL) {
1228 		SET(tp->t_state, TS_BUSY);
1229 		goto out;
1230 	}
1231 
1232 	SIMPLEQ_REMOVE_HEAD(&sc->sc_obuff_free, ub_link);
1233 
1234 	if (SIMPLEQ_FIRST(&sc->sc_obuff_free) == NULL)
1235 		SET(tp->t_state, TS_BUSY);
1236 
1237 	if (cnt > sc->sc_obufsize)
1238 		cnt = sc->sc_obufsize;
1239 
1240 	if (sc->sc_methods->ucom_write != NULL)
1241 		sc->sc_methods->ucom_write(sc->sc_parent, sc->sc_portno,
1242 		    ub->ub_data, data, &cnt);
1243 	else
1244 		memcpy(ub->ub_data, data, cnt);
1245 
1246 	ub->ub_len = cnt;
1247 	ub->ub_index = 0;
1248 
1249 	SIMPLEQ_INSERT_TAIL(&sc->sc_obuff_full, ub, ub_link);
1250 
1251 	kpreempt_disable();
1252 	softint_schedule(sc->sc_si);
1253 	kpreempt_enable();
1254 
1255  out:
1256 	DPRINTF("... done", 0, 0, 0, 0);
1257 	return;
1258 }
1259 
1260 void
ucomstop(struct tty * tp,int flag)1261 ucomstop(struct tty *tp, int flag)
1262 {
1263 #if 0
1264 	const int unit = UCOMUNIT(tp->t_dev);
1265 	struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
1266 
1267 	mutex_enter(&sc->sc_lock);
1268 	ttylock(tp);
1269 	if (ISSET(tp->t_state, TS_BUSY)) {
1270 		/* obuff_full -> obuff_free? */
1271 		/* sc->sc_tx_stopped = 1; */
1272 		if (!ISSET(tp->t_state, TS_TTSTOP))
1273 			SET(tp->t_state, TS_FLUSH);
1274 	}
1275 	ttyunlock(tp);
1276 	mutex_exit(&sc->sc_lock);
1277 #endif
1278 }
1279 
1280 static void
ucom_write_status(struct ucom_softc * sc,struct ucom_buffer * ub,usbd_status err)1281 ucom_write_status(struct ucom_softc *sc, struct ucom_buffer *ub,
1282     usbd_status err)
1283 {
1284 	struct tty *tp = sc->sc_tty;
1285 	uint32_t cc = ub->ub_len;
1286 
1287 	KASSERT(mutex_owned(&sc->sc_lock));
1288 
1289 	switch (err) {
1290 	case USBD_IN_PROGRESS:
1291 		ub->ub_index = ub->ub_len;
1292 		break;
1293 	case USBD_STALLED:
1294 		ub->ub_index = 0;
1295 		kpreempt_disable();
1296 		softint_schedule(sc->sc_si);
1297 		kpreempt_enable();
1298 		break;
1299 	case USBD_NORMAL_COMPLETION:
1300 		usbd_get_xfer_status(ub->ub_xfer, NULL, NULL, &cc, NULL);
1301 		rnd_add_uint32(&sc->sc_rndsource, cc);
1302 		/*FALLTHROUGH*/
1303 	default:
1304 		SIMPLEQ_REMOVE_HEAD(&sc->sc_obuff_full, ub_link);
1305 		SIMPLEQ_INSERT_TAIL(&sc->sc_obuff_free, ub, ub_link);
1306 		cc -= sc->sc_opkthdrlen;
1307 
1308 		ttylock(tp);
1309 		CLR(tp->t_state, TS_BUSY);
1310 		if (ISSET(tp->t_state, TS_FLUSH))
1311 			CLR(tp->t_state, TS_FLUSH);
1312 		else
1313 			ndflush(&tp->t_outq, cc);
1314 		ttyunlock(tp);
1315 
1316 		if (err != USBD_CANCELLED && err != USBD_IOERROR &&
1317 		    !sc->sc_closing) {
1318 			if ((ub = SIMPLEQ_FIRST(&sc->sc_obuff_full)) != NULL)
1319 				ucom_submit_write(sc, ub);
1320 
1321 			ttylock(tp);
1322 			(*tp->t_linesw->l_start)(tp);
1323 			ttyunlock(tp);
1324 		}
1325 		break;
1326 	}
1327 }
1328 
1329 static void
ucom_submit_write(struct ucom_softc * sc,struct ucom_buffer * ub)1330 ucom_submit_write(struct ucom_softc *sc, struct ucom_buffer *ub)
1331 {
1332 
1333 	KASSERT(mutex_owned(&sc->sc_lock));
1334 
1335 	usbd_setup_xfer(ub->ub_xfer, sc, ub->ub_data, ub->ub_len,
1336 	    0, USBD_NO_TIMEOUT, ucomwritecb);
1337 
1338 	ucom_write_status(sc, ub, usbd_transfer(ub->ub_xfer));
1339 }
1340 
1341 static void
ucomwritecb(struct usbd_xfer * xfer,void * p,usbd_status status)1342 ucomwritecb(struct usbd_xfer *xfer, void *p, usbd_status status)
1343 {
1344 	struct ucom_softc *sc = (struct ucom_softc *)p;
1345 
1346 	mutex_enter(&sc->sc_lock);
1347 	ucom_write_status(sc, SIMPLEQ_FIRST(&sc->sc_obuff_full), status);
1348 	mutex_exit(&sc->sc_lock);
1349 
1350 }
1351 
1352 static void
ucom_softintr(void * arg)1353 ucom_softintr(void *arg)
1354 {
1355 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1356 
1357 	struct ucom_softc *sc = arg;
1358 	struct tty *tp = sc->sc_tty;
1359 
1360 	mutex_enter(&sc->sc_lock);
1361 	ttylock(tp);
1362 	if (!ISSET(tp->t_state, TS_ISOPEN)) {
1363 		ttyunlock(tp);
1364 		mutex_exit(&sc->sc_lock);
1365 		return;
1366 	}
1367 	ttyunlock(tp);
1368 
1369 	struct ucom_buffer *ub = SIMPLEQ_FIRST(&sc->sc_obuff_full);
1370 
1371 	if (ub != NULL && ub->ub_index == 0)
1372 		ucom_submit_write(sc, ub);
1373 
1374 	if (sc->sc_rx_unblock)
1375 		ucom_read_complete(sc);
1376 
1377 	mutex_exit(&sc->sc_lock);
1378 }
1379 
1380 static void
ucom_read_complete(struct ucom_softc * sc)1381 ucom_read_complete(struct ucom_softc *sc)
1382 {
1383 	int (*rint)(int, struct tty *);
1384 	struct ucom_buffer *ub;
1385 	struct tty *tp;
1386 
1387 	KASSERT(mutex_owned(&sc->sc_lock));
1388 
1389 	tp = sc->sc_tty;
1390 	rint = tp->t_linesw->l_rint;
1391 	ub = SIMPLEQ_FIRST(&sc->sc_ibuff_full);
1392 
1393 	while (ub != NULL && !sc->sc_rx_stopped) {
1394 
1395 		/* XXX ttyinput takes ttylock */
1396 		while (ub->ub_index < ub->ub_len && !sc->sc_rx_stopped) {
1397 			/* Give characters to tty layer. */
1398 			if ((*rint)(ub->ub_data[ub->ub_index], tp) == -1) {
1399 				/* Overflow: drop remainder */
1400 				ub->ub_index = ub->ub_len;
1401 			} else
1402 				ub->ub_index++;
1403 		}
1404 
1405 		if (ub->ub_index == ub->ub_len) {
1406 			SIMPLEQ_REMOVE_HEAD(&sc->sc_ibuff_full, ub_link);
1407 			ucomsubmitread(sc, ub);
1408 			ub = SIMPLEQ_FIRST(&sc->sc_ibuff_full);
1409 		}
1410 	}
1411 
1412 	sc->sc_rx_unblock = (ub != NULL);
1413 }
1414 
1415 static int
ucomsubmitread(struct ucom_softc * sc,struct ucom_buffer * ub)1416 ucomsubmitread(struct ucom_softc *sc, struct ucom_buffer *ub)
1417 {
1418 	usbd_status err;
1419 
1420 	KASSERT(mutex_owned(&sc->sc_lock));
1421 
1422 	usbd_setup_xfer(ub->ub_xfer, sc, ub->ub_data, sc->sc_ibufsize,
1423 	    USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, ucomreadcb);
1424 
1425 	if ((err = usbd_transfer(ub->ub_xfer)) != USBD_IN_PROGRESS) {
1426 		/* XXX: Recover from this, please! */
1427 		printf("%s: err=%s\n", __func__, usbd_errstr(err));
1428 		return EIO;
1429 	}
1430 
1431 	SIMPLEQ_INSERT_TAIL(&sc->sc_ibuff_empty, ub, ub_link);
1432 
1433 	return 0;
1434 }
1435 
1436 static void
ucomreadcb(struct usbd_xfer * xfer,void * p,usbd_status status)1437 ucomreadcb(struct usbd_xfer *xfer, void *p, usbd_status status)
1438 {
1439 	struct ucom_softc *sc = (struct ucom_softc *)p;
1440 	struct ucom_buffer *ub;
1441 	uint32_t cc;
1442 	u_char *cp;
1443 
1444 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1445 
1446 	mutex_enter(&sc->sc_lock);
1447 
1448 	if (status == USBD_CANCELLED || status == USBD_IOERROR ||
1449 	    sc->sc_closing) {
1450 		DPRINTF("... done (status %jd closing %jd)",
1451 		    status, sc->sc_closing, 0, 0);
1452 		mutex_exit(&sc->sc_lock);
1453 		return;
1454 	}
1455 
1456 	ub = SIMPLEQ_FIRST(&sc->sc_ibuff_empty);
1457 	SIMPLEQ_REMOVE_HEAD(&sc->sc_ibuff_empty, ub_link);
1458 
1459 	if (status != USBD_NORMAL_COMPLETION) {
1460 		if (status == USBD_STALLED) {
1461 			usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
1462 		} else {
1463 			printf("ucomreadcb: wonky status=%s\n",
1464 			    usbd_errstr(status));
1465 		}
1466 
1467 		DPRINTF("... done (status %jd)", status, 0, 0, 0);
1468 		/* re-adds ub to sc_ibuff_empty */
1469 		ucomsubmitread(sc, ub);
1470 		mutex_exit(&sc->sc_lock);
1471 		return;
1472 	}
1473 
1474 	usbd_get_xfer_status(xfer, NULL, (void *)&cp, &cc, NULL);
1475 
1476 #ifdef UCOM_DEBUG
1477 	/* This is triggered by uslsa(4) occasionally. */
1478 	if ((ucomdebug > 0) && (cc == 0)) {
1479 		device_printf(sc->sc_dev, "ucomreadcb: zero length xfer!\n");
1480 	}
1481 #endif
1482 	KDASSERT(cp == ub->ub_data);
1483 
1484 	rnd_add_uint32(&sc->sc_rndsource, cc);
1485 
1486 	if (sc->sc_state != UCOM_OPEN) {
1487 		/* Go around again - we're not quite ready */
1488 		/* re-adds ub to sc_ibuff_empty */
1489 		ucomsubmitread(sc, ub);
1490 		mutex_exit(&sc->sc_lock);
1491 		DPRINTF("... done (not open)", 0, 0, 0, 0);
1492 		return;
1493 	}
1494 
1495 	mutex_exit(&sc->sc_lock);
1496 	if (sc->sc_methods->ucom_read != NULL) {
1497 		sc->sc_methods->ucom_read(sc->sc_parent, sc->sc_portno,
1498 		    &cp, &cc);
1499 		ub->ub_index = (u_int)(cp - ub->ub_data);
1500 	} else
1501 		ub->ub_index = 0;
1502 
1503 	ub->ub_len = cc;
1504 
1505 	mutex_enter(&sc->sc_lock);
1506 	SIMPLEQ_INSERT_TAIL(&sc->sc_ibuff_full, ub, ub_link);
1507 	ucom_read_complete(sc);
1508 	mutex_exit(&sc->sc_lock);
1509 
1510 	DPRINTF("... done", 0, 0, 0, 0);
1511 }
1512 
1513 static void
ucom_cleanup(struct ucom_softc * sc,int flag)1514 ucom_cleanup(struct ucom_softc *sc, int flag)
1515 {
1516 	struct tty *tp = sc->sc_tty;
1517 
1518 	UCOMHIST_FUNC(); UCOMHIST_CALLED();
1519 
1520 	DPRINTF("closing pipes", 0, 0, 0, 0);
1521 
1522 	/*
1523 	 * Close the tty and interrupt any pending opens waiting for
1524 	 * carrier so they restart or give up.  This may flush data.
1525 	 */
1526 	(*tp->t_linesw->l_close)(tp, flag);
1527 	ttyclose(tp);
1528 
1529 	/*
1530 	 * Interrupt any pending xfers and cause them to fail promptly.
1531 	 * New xfers will only be submitted under the lock after
1532 	 * sc_closing is cleared.
1533 	 */
1534 	usbd_abort_pipe(sc->sc_bulkin_pipe);
1535 	usbd_abort_pipe(sc->sc_bulkout_pipe);
1536 
1537 	/*
1538 	 * Hang up the phone and start the timer before we can make a
1539 	 * call again, if necessary.
1540 	 */
1541 	ucom_shutdown(sc);
1542 }
1543 
1544 #endif /* NUCOM > 0 */
1545 
1546 int
ucomprint(void * aux,const char * pnp)1547 ucomprint(void *aux, const char *pnp)
1548 {
1549 	struct ucom_attach_args *ucaa = aux;
1550 
1551 	if (pnp)
1552 		aprint_normal("ucom at %s", pnp);
1553 	if (ucaa->ucaa_portno != UCOM_UNK_PORTNO)
1554 		aprint_normal(" portno %d", ucaa->ucaa_portno);
1555 	return UNCONF;
1556 }
1557 
1558 int
ucomsubmatch(device_t parent,cfdata_t cf,const int * ldesc,void * aux)1559 ucomsubmatch(device_t parent, cfdata_t cf,
1560 	     const int *ldesc, void *aux)
1561 {
1562 	struct ucom_attach_args *ucaa = aux;
1563 
1564 	if (ucaa->ucaa_portno != UCOM_UNK_PORTNO &&
1565 	    cf->cf_loc[UCOMBUSCF_PORTNO] != UCOMBUSCF_PORTNO_DEFAULT &&
1566 	    cf->cf_loc[UCOMBUSCF_PORTNO] != ucaa->ucaa_portno)
1567 		return 0;
1568 	return config_match(parent, cf, aux);
1569 }
1570