xref: /freebsd/sys/dev/uart/uart_tty.c (revision 657729a89dd578d8cfc70d6616f5c65a48a8b33a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2003 Marcel Moolenaar
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/conf.h>
36 #include <sys/cons.h>
37 #include <sys/fcntl.h>
38 #include <sys/interrupt.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/reboot.h>
42 #include <machine/bus.h>
43 #include <sys/rman.h>
44 #include <sys/tty.h>
45 #include <machine/resource.h>
46 #include <machine/stdarg.h>
47 
48 #include <dev/uart/uart.h>
49 #include <dev/uart/uart_bus.h>
50 #include <dev/uart/uart_cpu.h>
51 
52 #include "uart_if.h"
53 
54 static cn_probe_t uart_cnprobe;
55 static cn_init_t uart_cninit;
56 static cn_init_t uart_cnresume;
57 static cn_term_t uart_cnterm;
58 static cn_getc_t uart_cngetc;
59 static cn_putc_t uart_cnputc;
60 static cn_grab_t uart_cngrab;
61 static cn_ungrab_t uart_cnungrab;
62 
63 static tsw_open_t uart_tty_open;
64 static tsw_close_t uart_tty_close;
65 static tsw_outwakeup_t uart_tty_outwakeup;
66 static tsw_inwakeup_t uart_tty_inwakeup;
67 static tsw_ioctl_t uart_tty_ioctl;
68 static tsw_param_t uart_tty_param;
69 static tsw_modem_t uart_tty_modem;
70 static tsw_free_t uart_tty_free;
71 static tsw_busy_t uart_tty_busy;
72 
73 CONSOLE_DRIVER(
74 	uart,
75 	.cn_resume = uart_cnresume,
76 );
77 
78 static struct uart_devinfo uart_console;
79 
80 /* TTY swi(9) event. Allows all uart soft handlers to share one ithread. */
81 static struct intr_event *tty_intr_event;
82 
83 static void
84 uart_cnprobe(struct consdev *cp)
85 {
86 
87 	cp->cn_pri = CN_DEAD;
88 
89 	KASSERT(uart_console.cookie == NULL, ("foo"));
90 
91 	if (uart_cpu_getdev(UART_DEV_CONSOLE, &uart_console))
92 		return;
93 
94 	if (uart_probe(&uart_console))
95 		return;
96 
97 	strlcpy(cp->cn_name, uart_driver_name, sizeof(cp->cn_name));
98 	cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
99 	cp->cn_arg = &uart_console;
100 }
101 
102 static void
103 uart_cninit(struct consdev *cp)
104 {
105 	struct uart_devinfo *di;
106 
107 	/*
108 	 * Yedi trick: we need to be able to define cn_dev before we go
109 	 * single- or multi-user. The problem is that we don't know at
110 	 * this time what the device will be. Hence, we need to link from
111 	 * the uart_devinfo to the consdev that corresponds to it so that
112 	 * we can define cn_dev in uart_bus_attach() when we find the
113 	 * device during bus enumeration. That's when we'll know what the
114 	 * the unit number will be.
115 	 */
116 	di = cp->cn_arg;
117 	KASSERT(di->cookie == NULL, ("foo"));
118 	di->cookie = cp;
119 	di->type = UART_DEV_CONSOLE;
120 	uart_add_sysdev(di);
121 	uart_init(di);
122 }
123 
124 static void
125 uart_cnresume(struct consdev *cp)
126 {
127 
128 	uart_init(cp->cn_arg);
129 }
130 
131 static void
132 uart_cnterm(struct consdev *cp)
133 {
134 
135 	uart_term(cp->cn_arg);
136 }
137 
138 static void
139 uart_cngrab(struct consdev *cp)
140 {
141 
142 	uart_grab(cp->cn_arg);
143 }
144 
145 static void
146 uart_cnungrab(struct consdev *cp)
147 {
148 
149 	uart_ungrab(cp->cn_arg);
150 }
151 
152 static void
153 uart_cnputc(struct consdev *cp, int c)
154 {
155 
156 	uart_putc(cp->cn_arg, c);
157 }
158 
159 static int
160 uart_cngetc(struct consdev *cp)
161 {
162 
163 	return (uart_poll(cp->cn_arg));
164 }
165 
166 static int
167 uart_tty_open(struct tty *tp)
168 {
169 	struct uart_softc *sc;
170 
171 	sc = tty_softc(tp);
172 
173 	if (sc == NULL || sc->sc_leaving)
174 		return (ENXIO);
175 
176 	sc->sc_opened = 1;
177 	return (0);
178 }
179 
180 static void
181 uart_tty_close(struct tty *tp)
182 {
183 	struct uart_softc *sc;
184 
185 	sc = tty_softc(tp);
186 	if (sc == NULL || sc->sc_leaving || !sc->sc_opened)
187 		return;
188 
189 	if (sc->sc_hwiflow)
190 		UART_IOCTL(sc, UART_IOCTL_IFLOW, 0);
191 	if (sc->sc_hwoflow)
192 		UART_IOCTL(sc, UART_IOCTL_OFLOW, 0);
193 	if (sc->sc_sysdev == NULL)
194 		UART_SETSIG(sc, SER_DDTR | SER_DRTS);
195 
196 	wakeup(sc);
197 	sc->sc_opened = 0;
198 }
199 
200 static void
201 uart_tty_outwakeup(struct tty *tp)
202 {
203 	struct uart_softc *sc;
204 
205 	sc = tty_softc(tp);
206 	if (sc == NULL || sc->sc_leaving)
207 		return;
208 
209 	if (sc->sc_txbusy)
210 		return;
211 
212 	/*
213 	 * Respect RTS/CTS (output) flow control if enabled and not already
214 	 * handled by hardware.
215 	 */
216 	if ((tp->t_termios.c_cflag & CCTS_OFLOW) && !sc->sc_hwoflow &&
217 	    !(sc->sc_hwsig & SER_CTS))
218 		return;
219 
220 	sc->sc_txdatasz = ttydisc_getc(tp, sc->sc_txbuf, sc->sc_txfifosz);
221 	if (sc->sc_txdatasz != 0)
222 		UART_TRANSMIT(sc);
223 }
224 
225 static void
226 uart_tty_inwakeup(struct tty *tp)
227 {
228 	struct uart_softc *sc;
229 
230 	sc = tty_softc(tp);
231 	if (sc == NULL || sc->sc_leaving)
232 		return;
233 
234 	if (sc->sc_isquelch) {
235 		if ((tp->t_termios.c_cflag & CRTS_IFLOW) && !sc->sc_hwiflow)
236 			UART_SETSIG(sc, SER_DRTS|SER_RTS);
237 		sc->sc_isquelch = 0;
238 		uart_sched_softih(sc, SER_INT_RXREADY);
239 	}
240 }
241 
242 static int
243 uart_tty_ioctl(struct tty *tp, u_long cmd, caddr_t data,
244     struct thread *td __unused)
245 {
246 	struct uart_softc *sc;
247 
248 	sc = tty_softc(tp);
249 
250 	switch (cmd) {
251 	case TIOCSBRK:
252 		UART_IOCTL(sc, UART_IOCTL_BREAK, 1);
253 		return (0);
254 	case TIOCCBRK:
255 		UART_IOCTL(sc, UART_IOCTL_BREAK, 0);
256 		return (0);
257 	default:
258 		return pps_ioctl(cmd, data, &sc->sc_pps);
259 	}
260 }
261 
262 static int
263 uart_tty_param(struct tty *tp, struct termios *t)
264 {
265 	struct uart_softc *sc;
266 	int databits, parity, stopbits;
267 
268 	sc = tty_softc(tp);
269 	if (sc == NULL || sc->sc_leaving)
270 		return (ENODEV);
271 	if (t->c_ispeed != t->c_ospeed && t->c_ospeed != 0)
272 		return (EINVAL);
273 	if (t->c_ospeed == 0) {
274 		UART_SETSIG(sc, SER_DDTR | SER_DRTS);
275 		return (0);
276 	}
277 	switch (t->c_cflag & CSIZE) {
278 	case CS5:	databits = 5; break;
279 	case CS6:	databits = 6; break;
280 	case CS7:	databits = 7; break;
281 	default:	databits = 8; break;
282 	}
283 	stopbits = (t->c_cflag & CSTOPB) ? 2 : 1;
284 	if (t->c_cflag & PARENB)
285 		parity = (t->c_cflag & PARODD) ? UART_PARITY_ODD :
286 		    UART_PARITY_EVEN;
287 	else
288 		parity = UART_PARITY_NONE;
289 	if (UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity) != 0)
290 		return (EINVAL);
291 	if ((t->c_cflag & CNO_RTSDTR) == 0)
292 		UART_SETSIG(sc, SER_DDTR | SER_DTR);
293 	/* Set input flow control state. */
294 	if (!sc->sc_hwiflow) {
295 		if ((t->c_cflag & CRTS_IFLOW) && sc->sc_isquelch)
296 			UART_SETSIG(sc, SER_DRTS);
297 		else {
298 			if ((t->c_cflag & CNO_RTSDTR) == 0)
299 				UART_SETSIG(sc, SER_DRTS | SER_RTS);
300 		}
301 	} else
302 		UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW));
303 	/* Set output flow control state. */
304 	if (sc->sc_hwoflow)
305 		UART_IOCTL(sc, UART_IOCTL_OFLOW, (t->c_cflag & CCTS_OFLOW));
306 
307 	return (0);
308 }
309 
310 static int
311 uart_tty_modem(struct tty *tp, int biton, int bitoff)
312 {
313 	struct uart_softc *sc;
314 
315 	sc = tty_softc(tp);
316 	if (biton != 0 || bitoff != 0)
317 		UART_SETSIG(sc, SER_DELTA(bitoff | biton) | biton);
318 	return (sc->sc_hwsig);
319 }
320 
321 void
322 uart_tty_intr(void *arg)
323 {
324 	struct uart_softc *sc = arg;
325 	struct tty *tp;
326 	int c, err = 0, pend, sig, xc;
327 
328 	if (sc->sc_leaving)
329 		return;
330 
331 	pend = atomic_readandclear_32(&sc->sc_ttypend);
332 	if (!(pend & SER_INT_MASK))
333 		return;
334 
335 	tp = sc->sc_u.u_tty.tp;
336 	tty_lock(tp);
337 
338 	if (pend & SER_INT_RXREADY) {
339 		while (!uart_rx_empty(sc) && !sc->sc_isquelch) {
340 			xc = uart_rx_peek(sc);
341 			c = xc & 0xff;
342 			if (xc & UART_STAT_FRAMERR)
343 				err |= TRE_FRAMING;
344 			if (xc & UART_STAT_OVERRUN)
345 				err |= TRE_OVERRUN;
346 			if (xc & UART_STAT_PARERR)
347 				err |= TRE_PARITY;
348 			if (ttydisc_rint(tp, c, err) != 0) {
349 				sc->sc_isquelch = 1;
350 				if ((tp->t_termios.c_cflag & CRTS_IFLOW) &&
351 				    !sc->sc_hwiflow)
352 					UART_SETSIG(sc, SER_DRTS);
353 			} else
354 				uart_rx_next(sc);
355 		}
356 	}
357 
358 	if (pend & SER_INT_BREAK)
359 		ttydisc_rint(tp, 0, TRE_BREAK);
360 
361 	if (pend & SER_INT_SIGCHG) {
362 		sig = pend & SER_INT_SIGMASK;
363 		if (sig & SER_DDCD)
364 			ttydisc_modem(tp, sig & SER_DCD);
365 		if (sig & SER_DCTS)
366 			uart_tty_outwakeup(tp);
367 	}
368 
369 	if (pend & SER_INT_TXIDLE)
370 		uart_tty_outwakeup(tp);
371 	ttydisc_rint_done(tp);
372 	tty_unlock(tp);
373 }
374 
375 static void
376 uart_tty_free(void *arg __unused)
377 {
378 
379 	/*
380 	 * XXX: uart(4) could reuse the device unit number before it is
381 	 * being freed by the TTY layer. We should use this hook to free
382 	 * the device unit number, but unfortunately newbus does not
383 	 * seem to support such a construct.
384 	 */
385 }
386 
387 static bool
388 uart_tty_busy(struct tty *tp)
389 {
390 	struct uart_softc *sc;
391 
392 	sc = tty_softc(tp);
393 	if (sc == NULL || sc->sc_leaving)
394                 return (FALSE);
395 
396 	return (sc->sc_txbusy);
397 }
398 
399 static struct ttydevsw uart_tty_class = {
400 	.tsw_flags	= TF_INITLOCK|TF_CALLOUT,
401 	.tsw_open	= uart_tty_open,
402 	.tsw_close	= uart_tty_close,
403 	.tsw_outwakeup	= uart_tty_outwakeup,
404 	.tsw_inwakeup	= uart_tty_inwakeup,
405 	.tsw_ioctl	= uart_tty_ioctl,
406 	.tsw_param	= uart_tty_param,
407 	.tsw_modem	= uart_tty_modem,
408 	.tsw_free	= uart_tty_free,
409 	.tsw_busy	= uart_tty_busy,
410 };
411 
412 int
413 uart_tty_attach(struct uart_softc *sc)
414 {
415 	struct tty *tp;
416 	int unit;
417 
418 	sc->sc_u.u_tty.tp = tp = tty_alloc(&uart_tty_class, sc);
419 
420 	unit = device_get_unit(sc->sc_dev);
421 
422 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
423 		sprintf(((struct consdev *)sc->sc_sysdev->cookie)->cn_name,
424 		    "ttyu%r", unit);
425 		tty_init_console(tp, sc->sc_sysdev->baudrate);
426 	}
427 
428 	swi_add(&tty_intr_event, uart_driver_name, uart_tty_intr, sc, SWI_TTY,
429 	    INTR_TYPE_TTY, &sc->sc_softih);
430 
431 	tty_makedev(tp, NULL, "u%r", unit);
432 
433 	return (0);
434 }
435 
436 int
437 uart_tty_detach(struct uart_softc *sc)
438 {
439 	struct tty *tp;
440 
441 	tp = sc->sc_u.u_tty.tp;
442 
443 	tty_lock(tp);
444 	swi_remove(sc->sc_softih);
445 	tty_rel_gone(tp);
446 
447 	return (0);
448 }
449 
450 struct mtx *
451 uart_tty_getlock(struct uart_softc *sc)
452 {
453 
454 	if (sc->sc_u.u_tty.tp != NULL)
455 		return (tty_getlock(sc->sc_u.u_tty.tp));
456 	else
457 		return (NULL);
458 }
459