xref: /freebsd/sys/dev/uart/uart_tty.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
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 static cn_probe_t uart_cnprobe;
54 static cn_init_t uart_cninit;
55 static cn_term_t uart_cnterm;
56 static cn_getc_t uart_cngetc;
57 static cn_checkc_t uart_cncheckc;
58 static cn_putc_t uart_cnputc;
59 
60 CONS_DRIVER(uart, uart_cnprobe, uart_cninit, uart_cnterm, uart_cngetc,
61     uart_cncheckc, uart_cnputc, NULL);
62 
63 static struct uart_devinfo uart_console;
64 
65 static void
66 uart_cnprobe(struct consdev *cp)
67 {
68 
69 	cp->cn_pri = CN_DEAD;
70 
71 	KASSERT(uart_console.cookie == NULL, ("foo"));
72 
73 	if (uart_cpu_getdev(UART_DEV_CONSOLE, &uart_console))
74 		return;
75 
76 	if (uart_probe(&uart_console))
77 		return;
78 
79 	cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
80 	cp->cn_arg = &uart_console;
81 }
82 
83 static void
84 uart_cninit(struct consdev *cp)
85 {
86 	struct uart_devinfo *di;
87 
88 	/*
89 	 * Yedi trick: we need to be able to define cn_dev before we go
90 	 * single- or multi-user. The problem is that we don't know at
91 	 * this time what the device will be. Hence, we need to link from
92 	 * the uart_devinfo to the consdev that corresponds to it so that
93 	 * we can define cn_dev in uart_bus_attach() when we find the
94 	 * device during bus enumeration. That's when we'll know what the
95 	 * the unit number will be.
96 	 */
97 	di = cp->cn_arg;
98 	KASSERT(di->cookie == NULL, ("foo"));
99 	di->cookie = cp;
100 	di->type = UART_DEV_CONSOLE;
101 	uart_add_sysdev(di);
102 	uart_init(di);
103 }
104 
105 static void
106 uart_cnterm(struct consdev *cp)
107 {
108 
109 	uart_term(cp->cn_arg);
110 }
111 
112 static void
113 uart_cnputc(struct consdev *cp, int c)
114 {
115 
116 	uart_putc(cp->cn_arg, c);
117 }
118 
119 static int
120 uart_cncheckc(struct consdev *cp)
121 {
122 
123 	return (uart_poll(cp->cn_arg));
124 }
125 
126 static int
127 uart_cngetc(struct consdev *cp)
128 {
129 
130 	return (uart_getc(cp->cn_arg));
131 }
132 
133 static int
134 uart_tty_open(struct tty *tp, struct cdev *dev)
135 {
136 	struct uart_softc *sc;
137 
138 	sc = tp->t_sc;
139 	sc->sc_opened = 1;
140 	return (0);
141 }
142 
143 static void
144 uart_tty_close(struct tty *tp)
145 {
146 	struct uart_softc *sc;
147 
148 	sc = tp->t_sc;
149 	if (sc == NULL || sc->sc_leaving || !sc->sc_opened)
150 		return;
151 
152 	if (sc->sc_hwiflow)
153 		UART_IOCTL(sc, UART_IOCTL_IFLOW, 0);
154 	if (sc->sc_hwoflow)
155 		UART_IOCTL(sc, UART_IOCTL_OFLOW, 0);
156 	if (sc->sc_sysdev == NULL)
157 		UART_SETSIG(sc, SER_DDTR | SER_DRTS);
158 
159 	wakeup(sc);
160 	sc->sc_opened = 0;
161 	return;
162 }
163 
164 static void
165 uart_tty_oproc(struct tty *tp)
166 {
167 	struct uart_softc *sc;
168 
169 	sc = tp->t_sc;
170 	if (sc == NULL || sc->sc_leaving)
171 		return;
172 
173 	/*
174 	 * Handle input flow control. Note that if we have hardware support,
175 	 * we don't do anything here. We continue to receive until our buffer
176 	 * is full. At that time we cannot empty the UART itself and it will
177 	 * de-assert RTS for us. In that situation we're completely stuffed.
178 	 * Without hardware support, we need to toggle RTS ourselves.
179 	 */
180 	if ((tp->t_cflag & CRTS_IFLOW) && !sc->sc_hwiflow) {
181 		if ((tp->t_state & TS_TBLOCK) &&
182 		    (sc->sc_hwsig & SER_RTS))
183 			UART_SETSIG(sc, SER_DRTS);
184 		else if (!(tp->t_state & TS_TBLOCK) &&
185 		    !(sc->sc_hwsig & SER_RTS))
186 			UART_SETSIG(sc, SER_DRTS|SER_RTS);
187 	}
188 
189 	if (tp->t_state & TS_TTSTOP)
190 		return;
191 
192 	if ((tp->t_state & TS_BUSY) || sc->sc_txbusy)
193 		return;
194 
195 	if (tp->t_outq.c_cc == 0) {
196 		ttwwakeup(tp);
197 		return;
198 	}
199 
200 	sc->sc_txdatasz = q_to_b(&tp->t_outq, sc->sc_txbuf, sc->sc_txfifosz);
201 	tp->t_state |= TS_BUSY;
202 	UART_TRANSMIT(sc);
203 	ttwwakeup(tp);
204 }
205 
206 static int
207 uart_tty_param(struct tty *tp, struct termios *t)
208 {
209 	struct uart_softc *sc;
210 	int databits, parity, stopbits;
211 
212 	sc = tp->t_sc;
213 	if (sc == NULL || sc->sc_leaving)
214 		return (ENODEV);
215 	if (t->c_ispeed != t->c_ospeed && t->c_ospeed != 0)
216 		return (EINVAL);
217 	/* Fixate certain parameters for system devices. */
218 	if (sc->sc_sysdev != NULL) {
219 		t->c_ispeed = t->c_ospeed = sc->sc_sysdev->baudrate;
220 		t->c_cflag |= CLOCAL;
221 		t->c_cflag &= ~HUPCL;
222 	}
223 	if (t->c_ospeed == 0) {
224 		UART_SETSIG(sc, SER_DDTR | SER_DRTS);
225 		return (0);
226 	}
227 	switch (t->c_cflag & CSIZE) {
228 	case CS5:	databits = 5; break;
229 	case CS6:	databits = 6; break;
230 	case CS7:	databits = 7; break;
231 	default:	databits = 8; break;
232 	}
233 	stopbits = (t->c_cflag & CSTOPB) ? 2 : 1;
234 	if (t->c_cflag & PARENB)
235 		parity = (t->c_cflag & PARODD) ? UART_PARITY_ODD
236 		    : UART_PARITY_EVEN;
237 	else
238 		parity = UART_PARITY_NONE;
239 	if (UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity) != 0)
240 		return (EINVAL);
241 	UART_SETSIG(sc, SER_DDTR | SER_DTR);
242 	/* Set input flow control state. */
243 	if (!sc->sc_hwiflow) {
244 		if ((t->c_cflag & CRTS_IFLOW) && (tp->t_state & TS_TBLOCK))
245 			UART_SETSIG(sc, SER_DRTS);
246 		else
247 			UART_SETSIG(sc, SER_DRTS | SER_RTS);
248 	} else
249 		UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW));
250 	/* Set output flow control state. */
251 	if (sc->sc_hwoflow)
252 		UART_IOCTL(sc, UART_IOCTL_OFLOW, (t->c_cflag & CCTS_OFLOW));
253 	ttsetwater(tp);
254 	return (0);
255 }
256 
257 static int
258 uart_tty_modem(struct tty *tp, int biton, int bitoff)
259 {
260 	struct uart_softc *sc;
261 
262 	sc = tp->t_sc;
263 	if (biton != 0 || bitoff != 0)
264 		UART_SETSIG(sc, SER_DELTA(bitoff|biton) | biton);
265 	return (sc->sc_hwsig);
266 }
267 
268 static void
269 uart_tty_break(struct tty *tp, int state)
270 {
271 	struct uart_softc *sc;
272 
273 	sc = tp->t_sc;
274 	UART_IOCTL(sc, UART_IOCTL_BREAK, state);
275 }
276 
277 static void
278 uart_tty_stop(struct tty *tp, int rw)
279 {
280 	struct uart_softc *sc;
281 
282 	sc = tp->t_sc;
283 	if (sc == NULL || sc->sc_leaving)
284 		return;
285 	if (rw & FWRITE) {
286 		if (sc->sc_txbusy) {
287 			sc->sc_txbusy = 0;
288 			UART_FLUSH(sc, UART_FLUSH_TRANSMITTER);
289 		}
290 		tp->t_state &= ~TS_BUSY;
291 	}
292 	if (rw & FREAD) {
293 		UART_FLUSH(sc, UART_FLUSH_RECEIVER);
294 		sc->sc_rxget = sc->sc_rxput = 0;
295 	}
296 }
297 
298 void
299 uart_tty_intr(void *arg)
300 {
301 	struct uart_softc *sc = arg;
302 	struct tty *tp;
303 	int c, pend, sig, xc;
304 
305 	if (sc->sc_leaving)
306 		return;
307 
308 	pend = atomic_readandclear_32(&sc->sc_ttypend);
309 	if (!(pend & UART_IPEND_MASK))
310 		return;
311 
312 	tp = sc->sc_u.u_tty.tp;
313 
314 	if (pend & UART_IPEND_RXREADY) {
315 		while (!uart_rx_empty(sc) && !(tp->t_state & TS_TBLOCK)) {
316 			xc = uart_rx_get(sc);
317 			c = xc & 0xff;
318 			if (xc & UART_STAT_FRAMERR)
319 				c |= TTY_FE;
320 			if (xc & UART_STAT_PARERR)
321 				c |= TTY_PE;
322 			ttyld_rint(tp, c);
323 		}
324 	}
325 
326 	if (pend & UART_IPEND_BREAK) {
327 		if (tp != NULL && !(tp->t_iflag & IGNBRK))
328 			ttyld_rint(tp, 0);
329 	}
330 
331 	if (pend & UART_IPEND_SIGCHG) {
332 		sig = pend & UART_IPEND_SIGMASK;
333 		if (sig & SER_DDCD)
334 			ttyld_modem(tp, sig & SER_DCD);
335 		if ((sig & SER_DCTS) && (tp->t_cflag & CCTS_OFLOW) &&
336 		    !sc->sc_hwoflow) {
337 			if (sig & SER_CTS) {
338 				tp->t_state &= ~TS_TTSTOP;
339 				ttyld_start(tp);
340 			} else
341 				tp->t_state |= TS_TTSTOP;
342 		}
343 	}
344 
345 	if (pend & UART_IPEND_TXIDLE) {
346 		tp->t_state &= ~TS_BUSY;
347 		ttyld_start(tp);
348 	}
349 }
350 
351 int
352 uart_tty_attach(struct uart_softc *sc)
353 {
354 	struct tty *tp;
355 	int unit;
356 
357 	tp = ttyalloc();
358 	sc->sc_u.u_tty.tp = tp;
359 	tp->t_sc = sc;
360 
361 	unit = device_get_unit(sc->sc_dev);
362 
363 	tp->t_oproc = uart_tty_oproc;
364 	tp->t_param = uart_tty_param;
365 	tp->t_stop = uart_tty_stop;
366 	tp->t_modem = uart_tty_modem;
367 	tp->t_break = uart_tty_break;
368 	tp->t_open = uart_tty_open;
369 	tp->t_close = uart_tty_close;
370 
371 	tp->t_pps = &sc->sc_pps;
372 
373 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
374 		sprintf(((struct consdev *)sc->sc_sysdev->cookie)->cn_name,
375 		    "ttyu%r", unit);
376 		ttyconsolemode(tp, 0);
377 	}
378 
379 	swi_add(&tty_ithd, uart_driver_name, uart_tty_intr, sc, SWI_TTY,
380 	    INTR_TYPE_TTY, &sc->sc_softih);
381 
382 	ttycreate(tp, NULL, 0, MINOR_CALLOUT, "u%r", unit);
383 
384 	return (0);
385 }
386 
387 int uart_tty_detach(struct uart_softc *sc)
388 {
389 	struct tty *tp;
390 
391 	tp = sc->sc_u.u_tty.tp;
392 	tp->t_pps = NULL;
393 	ttygone(tp);
394 	ithread_remove_handler(sc->sc_softih);
395 	ttyfree(tp);
396 
397 	return (0);
398 }
399