xref: /freebsd/sys/dev/uart/uart_tty.c (revision 74bf4e164ba5851606a27d4feff27717452583e5)
1 /*
2  * Copyright (c) 2003 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/cons.h>
35 #include <sys/fcntl.h>
36 #include <sys/interrupt.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/reboot.h>
40 #include <machine/bus.h>
41 #include <sys/rman.h>
42 #include <sys/termios.h>
43 #include <sys/tty.h>
44 #include <machine/resource.h>
45 #include <machine/stdarg.h>
46 
47 #include <dev/uart/uart.h>
48 #include <dev/uart/uart_bus.h>
49 #include <dev/uart/uart_cpu.h>
50 
51 #include "uart_if.h"
52 
53 #define	UART_MINOR_CALLOUT	0x10000
54 
55 static cn_probe_t uart_cnprobe;
56 static cn_init_t uart_cninit;
57 static cn_term_t uart_cnterm;
58 static cn_getc_t uart_cngetc;
59 static cn_checkc_t uart_cncheckc;
60 static cn_putc_t uart_cnputc;
61 
62 CONS_DRIVER(uart, uart_cnprobe, uart_cninit, uart_cnterm, uart_cngetc,
63     uart_cncheckc, uart_cnputc, NULL);
64 
65 static d_open_t uart_tty_open;
66 static d_close_t uart_tty_close;
67 static d_ioctl_t uart_tty_ioctl;
68 
69 static struct cdevsw uart_cdevsw = {
70 	.d_version =	D_VERSION,
71 	.d_open =	uart_tty_open,
72 	.d_close =	uart_tty_close,
73 	.d_ioctl =	uart_tty_ioctl,
74 	.d_name =	uart_driver_name,
75 	.d_flags =	D_TTY | D_NEEDGIANT,
76 };
77 
78 static struct uart_devinfo uart_console;
79 
80 static void
81 uart_cnprobe(struct consdev *cp)
82 {
83 
84 	cp->cn_pri = CN_DEAD;
85 
86 	KASSERT(uart_console.cookie == NULL, ("foo"));
87 
88 	if (uart_cpu_getdev(UART_DEV_CONSOLE, &uart_console))
89 		return;
90 
91 	if (uart_probe(&uart_console))
92 		return;
93 
94 	cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
95 	cp->cn_arg = &uart_console;
96 }
97 
98 static void
99 uart_cninit(struct consdev *cp)
100 {
101 	struct uart_devinfo *di;
102 
103 	/*
104 	 * Yedi trick: we need to be able to define cn_dev before we go
105 	 * single- or multi-user. The problem is that we don't know at
106 	 * this time what the device will be. Hence, we need to link from
107 	 * the uart_devinfo to the consdev that corresponds to it so that
108 	 * we can define cn_dev in uart_bus_attach() when we find the
109 	 * device during bus enumeration. That's when we'll know what the
110 	 * the unit number will be.
111 	 */
112 	di = cp->cn_arg;
113 	KASSERT(di->cookie == NULL, ("foo"));
114 	di->cookie = cp;
115 	di->type = UART_DEV_CONSOLE;
116 	uart_add_sysdev(di);
117 	uart_init(di);
118 }
119 
120 static void
121 uart_cnterm(struct consdev *cp)
122 {
123 
124 	uart_term(cp->cn_arg);
125 }
126 
127 static void
128 uart_cnputc(struct consdev *cp, int c)
129 {
130 
131 	uart_putc(cp->cn_arg, c);
132 }
133 
134 static int
135 uart_cncheckc(struct consdev *cp)
136 {
137 
138 	return (uart_poll(cp->cn_arg));
139 }
140 
141 static int
142 uart_cngetc(struct consdev *cp)
143 {
144 
145 	return (uart_getc(cp->cn_arg));
146 }
147 
148 static void
149 uart_tty_oproc(struct tty *tp)
150 {
151 	struct uart_softc *sc;
152 
153 	KASSERT(tp->t_dev != NULL, ("foo"));
154 	sc = tp->t_dev->si_drv1;
155 	if (sc == NULL || sc->sc_leaving)
156 		return;
157 
158 	/*
159 	 * Handle input flow control. Note that if we have hardware support,
160 	 * we don't do anything here. We continue to receive until our buffer
161 	 * is full. At that time we cannot empty the UART itself and it will
162 	 * de-assert RTS for us. In that situation we're completely stuffed.
163 	 * Without hardware support, we need to toggle RTS ourselves.
164 	 */
165 	if ((tp->t_cflag & CRTS_IFLOW) && !sc->sc_hwiflow) {
166 		if ((tp->t_state & TS_TBLOCK) &&
167 		    (sc->sc_hwsig & SER_RTS))
168 			UART_SETSIG(sc, SER_DRTS);
169 		else if (!(tp->t_state & TS_TBLOCK) &&
170 		    !(sc->sc_hwsig & SER_RTS))
171 			UART_SETSIG(sc, SER_DRTS|SER_RTS);
172 	}
173 
174 	if (tp->t_state & TS_TTSTOP)
175 		return;
176 
177 	if ((tp->t_state & TS_BUSY) || sc->sc_txbusy)
178 		return;
179 
180 	if (tp->t_outq.c_cc == 0) {
181 		ttwwakeup(tp);
182 		return;
183 	}
184 
185 	sc->sc_txdatasz = q_to_b(&tp->t_outq, sc->sc_txbuf, sc->sc_txfifosz);
186 	tp->t_state |= TS_BUSY;
187 	UART_TRANSMIT(sc);
188 	ttwwakeup(tp);
189 }
190 
191 static int
192 uart_tty_param(struct tty *tp, struct termios *t)
193 {
194 	struct uart_softc *sc;
195 	int databits, parity, stopbits;
196 
197 	KASSERT(tp->t_dev != NULL, ("foo"));
198 	sc = tp->t_dev->si_drv1;
199 	if (sc == NULL || sc->sc_leaving)
200 		return (ENODEV);
201 	if (t->c_ispeed != t->c_ospeed && t->c_ospeed != 0)
202 		return (EINVAL);
203 	/* Fixate certain parameters for system devices. */
204 	if (sc->sc_sysdev != NULL) {
205 		t->c_ispeed = t->c_ospeed = sc->sc_sysdev->baudrate;
206 		t->c_cflag |= CLOCAL;
207 		t->c_cflag &= ~HUPCL;
208 	}
209 	if (t->c_ospeed == 0) {
210 		UART_SETSIG(sc, SER_DDTR | SER_DRTS);
211 		return (0);
212 	}
213 	switch (t->c_cflag & CSIZE) {
214 	case CS5:	databits = 5; break;
215 	case CS6:	databits = 6; break;
216 	case CS7:	databits = 7; break;
217 	default:	databits = 8; break;
218 	}
219 	stopbits = (t->c_cflag & CSTOPB) ? 2 : 1;
220 	if (t->c_cflag & PARENB)
221 		parity = (t->c_cflag & PARODD) ? UART_PARITY_ODD
222 		    : UART_PARITY_EVEN;
223 	else
224 		parity = UART_PARITY_NONE;
225 	if (UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity) != 0)
226 		return (EINVAL);
227 	UART_SETSIG(sc, SER_DDTR | SER_DTR);
228 	/* Set input flow control state. */
229 	if (!sc->sc_hwiflow) {
230 		if ((t->c_cflag & CRTS_IFLOW) && (tp->t_state & TS_TBLOCK))
231 			UART_SETSIG(sc, SER_DRTS);
232 		else
233 			UART_SETSIG(sc, SER_DRTS | SER_RTS);
234 	} else
235 		UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW));
236 	/* Set output flow control state. */
237 	if (sc->sc_hwoflow)
238 		UART_IOCTL(sc, UART_IOCTL_OFLOW, (t->c_cflag & CCTS_OFLOW));
239 	ttsetwater(tp);
240 	return (0);
241 }
242 
243 static int
244 uart_tty_modem(struct tty *tp, int biton, int bitoff)
245 {
246 	struct uart_softc *sc;
247 
248 	sc = tp->t_dev->si_drv1;
249 	if (biton != 0 || bitoff != 0)
250 		UART_SETSIG(sc, SER_DELTA(bitoff|biton) | biton);
251 	return (sc->sc_hwsig);
252 }
253 
254 static void
255 uart_tty_break(struct tty *tp, int state)
256 {
257 	struct uart_softc *sc;
258 
259 	sc = tp->t_dev->si_drv1;
260 	UART_IOCTL(sc, UART_IOCTL_BREAK, state);
261 }
262 
263 static void
264 uart_tty_stop(struct tty *tp, int rw)
265 {
266 	struct uart_softc *sc;
267 
268 	KASSERT(tp->t_dev != NULL, ("foo"));
269 	sc = tp->t_dev->si_drv1;
270 	if (sc == NULL || sc->sc_leaving)
271 		return;
272 	if (rw & FWRITE) {
273 		if (sc->sc_txbusy) {
274 			sc->sc_txbusy = 0;
275 			UART_FLUSH(sc, UART_FLUSH_TRANSMITTER);
276 		}
277 		tp->t_state &= ~TS_BUSY;
278 	}
279 	if (rw & FREAD) {
280 		UART_FLUSH(sc, UART_FLUSH_RECEIVER);
281 		sc->sc_rxget = sc->sc_rxput = 0;
282 	}
283 }
284 
285 void
286 uart_tty_intr(void *arg)
287 {
288 	struct uart_softc *sc = arg;
289 	struct tty *tp;
290 	int c, pend, sig, xc;
291 
292 	if (sc->sc_leaving)
293 		return;
294 
295 	pend = atomic_readandclear_32(&sc->sc_ttypend);
296 	if (!(pend & UART_IPEND_MASK))
297 		return;
298 
299 	tp = sc->sc_u.u_tty.tp;
300 
301 	if (pend & UART_IPEND_RXREADY) {
302 		while (!uart_rx_empty(sc) && !(tp->t_state & TS_TBLOCK)) {
303 			xc = uart_rx_get(sc);
304 			c = xc & 0xff;
305 			if (xc & UART_STAT_FRAMERR)
306 				c |= TTY_FE;
307 			if (xc & UART_STAT_PARERR)
308 				c |= TTY_PE;
309 			ttyld_rint(tp, c);
310 		}
311 	}
312 
313 	if (pend & UART_IPEND_BREAK) {
314 		if (tp != NULL && !(tp->t_iflag & IGNBRK))
315 			ttyld_rint(tp, 0);
316 	}
317 
318 	if (pend & UART_IPEND_SIGCHG) {
319 		sig = pend & UART_IPEND_SIGMASK;
320 		if (sig & SER_DDCD)
321 			ttyld_modem(tp, sig & SER_DCD);
322 		if ((sig & SER_DCTS) && (tp->t_cflag & CCTS_OFLOW) &&
323 		    !sc->sc_hwoflow) {
324 			if (sig & SER_CTS) {
325 				tp->t_state &= ~TS_TTSTOP;
326 				ttyld_start(tp);
327 			} else
328 				tp->t_state |= TS_TTSTOP;
329 		}
330 	}
331 
332 	if (pend & UART_IPEND_TXIDLE) {
333 		tp->t_state &= ~TS_BUSY;
334 		ttyld_start(tp);
335 	}
336 }
337 
338 int
339 uart_tty_attach(struct uart_softc *sc)
340 {
341 	struct tty *tp;
342 
343 	tp = ttymalloc(NULL);
344 	sc->sc_u.u_tty.tp = tp;
345 
346 	sc->sc_u.u_tty.si[0] = make_dev(&uart_cdevsw,
347 	    device_get_unit(sc->sc_dev), UID_ROOT, GID_WHEEL, 0600, "ttyu%r",
348 	    device_get_unit(sc->sc_dev));
349 	sc->sc_u.u_tty.si[0]->si_drv1 = sc;
350 	sc->sc_u.u_tty.si[0]->si_tty = tp;
351 	sc->sc_u.u_tty.si[1] = make_dev(&uart_cdevsw,
352 	    device_get_unit(sc->sc_dev) | UART_MINOR_CALLOUT, UID_UUCP,
353 	    GID_DIALER, 0660, "uart%r", device_get_unit(sc->sc_dev));
354 	sc->sc_u.u_tty.si[1]->si_drv1 = sc;
355 	sc->sc_u.u_tty.si[1]->si_tty = tp;
356 
357 	tp->t_oproc = uart_tty_oproc;
358 	tp->t_param = uart_tty_param;
359 	tp->t_stop = uart_tty_stop;
360 	tp->t_modem = uart_tty_modem;
361 	tp->t_break = uart_tty_break;
362 
363 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
364 		sprintf(((struct consdev *)sc->sc_sysdev->cookie)->cn_name,
365 		    "ttyu%r", device_get_unit(sc->sc_dev));
366 	}
367 
368 	swi_add(&tty_ithd, uart_driver_name, uart_tty_intr, sc, SWI_TTY,
369 	    INTR_TYPE_TTY, &sc->sc_softih);
370 
371 	return (0);
372 }
373 
374 int uart_tty_detach(struct uart_softc *sc)
375 {
376 
377 	ithread_remove_handler(sc->sc_softih);
378 	destroy_dev(sc->sc_u.u_tty.si[0]);
379 	destroy_dev(sc->sc_u.u_tty.si[1]);
380 	/* ttyfree(sc->sc_u.u_tty.tp); */
381 
382 	return (0);
383 }
384 
385 static int
386 uart_tty_open(struct cdev *dev, int flags, int mode, struct thread *td)
387 {
388 	struct uart_softc *sc;
389 	struct tty *tp;
390 	int error;
391 
392  loop:
393 	sc = dev->si_drv1;
394 	if (sc == NULL || sc->sc_leaving)
395 		return (ENODEV);
396 
397 	tp = dev->si_tty;
398 
399 	if (sc->sc_opened) {
400 		KASSERT(tp->t_state & TS_ISOPEN, ("foo"));
401 		/*
402 		 * The device is open, so everything has been initialized.
403 		 * Handle conflicts.
404 		 */
405 		if (minor(dev) & UART_MINOR_CALLOUT) {
406 			if (!sc->sc_callout)
407 				return (EBUSY);
408 		} else {
409 			if (sc->sc_callout) {
410 				if (flags & O_NONBLOCK)
411 					return (EBUSY);
412 				error =	tsleep(sc, TTIPRI|PCATCH, "uartbi", 0);
413 				if (error)
414 					return (error);
415 				goto loop;
416 			}
417 		}
418 		if (tp->t_state & TS_XCLUDE && suser(td) != 0)
419 			return (EBUSY);
420 	} else {
421 		KASSERT(!(tp->t_state & TS_ISOPEN), ("foo"));
422 		/*
423 		 * The device isn't open, so there are no conflicts.
424 		 * Initialize it.  Initialization is done twice in many
425 		 * cases: to preempt sleeping callin opens if we are
426 		 * callout, and to complete a callin open after DCD rises.
427 		 */
428 		sc->sc_callout = (minor(dev) & UART_MINOR_CALLOUT) ? 1 : 0;
429 		tp->t_dev = dev;
430 
431 		tp->t_cflag = TTYDEF_CFLAG;
432 		tp->t_iflag = TTYDEF_IFLAG;
433 		tp->t_lflag = TTYDEF_LFLAG;
434 		tp->t_oflag = TTYDEF_OFLAG;
435 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
436 		ttychars(tp);
437 		error = uart_tty_param(tp, &tp->t_termios);
438 		if (error)
439 			return (error);
440 		/*
441 		 * Handle initial DCD.
442 		 */
443 		if ((sc->sc_hwsig & SER_DCD) || sc->sc_callout)
444 			ttyld_modem(tp, 1);
445 	}
446 	/*
447 	 * Wait for DCD if necessary.
448 	 */
449 	if (!(tp->t_state & TS_CARR_ON) && !sc->sc_callout &&
450 	    !(tp->t_cflag & CLOCAL) && !(flags & O_NONBLOCK)) {
451 		error = tsleep(TSA_CARR_ON(tp), TTIPRI|PCATCH, "uartdcd", 0);
452 		if (error)
453 			return (error);
454 		goto loop;
455 	}
456 	error = tty_open(dev, tp);
457 	if (error)
458 		return (error);
459 	error = ttyld_open(tp, dev);
460 	if (error)
461 		return (error);
462 
463 	KASSERT(tp->t_state & TS_ISOPEN, ("foo"));
464 	sc->sc_opened = 1;
465 	return (0);
466 }
467 
468 static int
469 uart_tty_close(struct cdev *dev, int flags, int mode, struct thread *td)
470 {
471 	struct uart_softc *sc;
472 	struct tty *tp;
473 
474 	sc = dev->si_drv1;
475 	if (sc == NULL || sc->sc_leaving)
476 		return (ENODEV);
477 	tp = dev->si_tty;
478 	if (!sc->sc_opened) {
479 		KASSERT(!(tp->t_state & TS_ISOPEN), ("foo"));
480 		return (0);
481 	}
482 	KASSERT(tp->t_state & TS_ISOPEN, ("foo"));
483 
484 	if (sc->sc_hwiflow)
485 		UART_IOCTL(sc, UART_IOCTL_IFLOW, 0);
486 	if (sc->sc_hwoflow)
487 		UART_IOCTL(sc, UART_IOCTL_OFLOW, 0);
488 	if (sc->sc_sysdev == NULL)
489 		UART_SETSIG(sc, SER_DDTR | SER_DRTS);
490 
491 	/* Disable pulse capturing. */
492 	sc->sc_pps.ppsparam.mode = 0;
493 
494 	ttyld_close(tp, flags);
495 	tty_close(tp);
496 	wakeup(sc);
497 	wakeup(TSA_CARR_ON(tp));
498 	KASSERT(!(tp->t_state & TS_ISOPEN), ("foo"));
499 	sc->sc_opened = 0;
500 	return (0);
501 }
502 
503 static int
504 uart_tty_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
505     struct thread *td)
506 {
507 	struct uart_softc *sc;
508 	struct tty *tp;
509 	int error;
510 
511 	sc = dev->si_drv1;
512 	if (sc == NULL || sc->sc_leaving)
513 		return (ENODEV);
514 
515 	tp = dev->si_tty;
516 	error = ttyioctl(dev, cmd, data, flags, td);
517 	if (error != ENOTTY)
518 		return (error);
519 
520 	error = pps_ioctl(cmd, data, &sc->sc_pps);
521 	if (error == ENODEV)
522 		error = ENOTTY;
523 	return (error);
524 }
525