blob: c9b64e73c9879d10d7bd7e7e4055bd257c083e73 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/drivers/char/core.c
3 *
4 * Driver core for serial ports
5 *
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
7 *
8 * Copyright 1999 ARM Limited
9 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/module.h>
26#include <linux/tty.h>
27#include <linux/slab.h>
28#include <linux/init.h>
29#include <linux/console.h>
30#include <linux/serial_core.h>
31#include <linux/smp_lock.h>
32#include <linux/device.h>
33#include <linux/serial.h> /* for serial_state and serial_icounter_struct */
34#include <linux/delay.h>
Arjan van de Venf392ecf2006-01-12 18:44:32 +000035#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
37#include <asm/irq.h>
38#include <asm/uaccess.h>
39
Linus Torvalds1da177e2005-04-16 15:20:36 -070040/*
41 * This is used to lock changes in serial line configuration.
42 */
Arjan van de Venf392ecf2006-01-12 18:44:32 +000043static DEFINE_MUTEX(port_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Ingo Molnar13e83592006-07-03 00:25:03 -070045/*
46 * lockdep: port->lock is initialized in two places, but we
47 * want only one lock-class:
48 */
49static struct lock_class_key port_lock_key;
50
Linus Torvalds1da177e2005-04-16 15:20:36 -070051#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
52
53#define uart_users(state) ((state)->count + ((state)->info ? (state)->info->blocked_open : 0))
54
55#ifdef CONFIG_SERIAL_CORE_CONSOLE
56#define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line)
57#else
58#define uart_console(port) (0)
59#endif
60
Alan Coxa46c9992008-02-08 04:18:53 -080061static void uart_change_speed(struct uart_state *state,
62 struct ktermios *old_termios);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063static void uart_wait_until_sent(struct tty_struct *tty, int timeout);
64static void uart_change_pm(struct uart_state *state, int pm_state);
65
66/*
67 * This routine is used by the interrupt handler to schedule processing in
68 * the software interrupt portion of the driver.
69 */
70void uart_write_wakeup(struct uart_port *port)
71{
72 struct uart_info *info = port->info;
Pavel Machekd5f735e2006-03-07 21:55:20 -080073 /*
74 * This means you called this function _after_ the port was
75 * closed. No cookie for you.
76 */
77 BUG_ON(!info);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 tasklet_schedule(&info->tlet);
79}
80
81static void uart_stop(struct tty_struct *tty)
82{
83 struct uart_state *state = tty->driver_data;
84 struct uart_port *port = state->port;
85 unsigned long flags;
86
87 spin_lock_irqsave(&port->lock, flags);
Russell Kingb129a8c2005-08-31 10:12:14 +010088 port->ops->stop_tx(port);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 spin_unlock_irqrestore(&port->lock, flags);
90}
91
92static void __uart_start(struct tty_struct *tty)
93{
94 struct uart_state *state = tty->driver_data;
95 struct uart_port *port = state->port;
96
97 if (!uart_circ_empty(&state->info->xmit) && state->info->xmit.buf &&
98 !tty->stopped && !tty->hw_stopped)
Russell Kingb129a8c2005-08-31 10:12:14 +010099 port->ops->start_tx(port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100}
101
102static void uart_start(struct tty_struct *tty)
103{
104 struct uart_state *state = tty->driver_data;
105 struct uart_port *port = state->port;
106 unsigned long flags;
107
108 spin_lock_irqsave(&port->lock, flags);
109 __uart_start(tty);
110 spin_unlock_irqrestore(&port->lock, flags);
111}
112
113static void uart_tasklet_action(unsigned long data)
114{
115 struct uart_state *state = (struct uart_state *)data;
116 tty_wakeup(state->info->tty);
117}
118
119static inline void
120uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear)
121{
122 unsigned long flags;
123 unsigned int old;
124
125 spin_lock_irqsave(&port->lock, flags);
126 old = port->mctrl;
127 port->mctrl = (old & ~clear) | set;
128 if (old != port->mctrl)
129 port->ops->set_mctrl(port, port->mctrl);
130 spin_unlock_irqrestore(&port->lock, flags);
131}
132
Alan Coxa46c9992008-02-08 04:18:53 -0800133#define uart_set_mctrl(port, set) uart_update_mctrl(port, set, 0)
134#define uart_clear_mctrl(port, clear) uart_update_mctrl(port, 0, clear)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
136/*
137 * Startup the port. This will be called once per open. All calls
138 * will be serialised by the per-port semaphore.
139 */
140static int uart_startup(struct uart_state *state, int init_hw)
141{
142 struct uart_info *info = state->info;
143 struct uart_port *port = state->port;
144 unsigned long page;
145 int retval = 0;
146
147 if (info->flags & UIF_INITIALIZED)
148 return 0;
149
150 /*
151 * Set the TTY IO error marker - we will only clear this
152 * once we have successfully opened the port. Also set
153 * up the tty->alt_speed kludge
154 */
Jayachandran Ca2436b22005-10-30 23:26:16 +0000155 set_bit(TTY_IO_ERROR, &info->tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
157 if (port->type == PORT_UNKNOWN)
158 return 0;
159
160 /*
161 * Initialise and allocate the transmit and temporary
162 * buffer.
163 */
164 if (!info->xmit.buf) {
165 page = get_zeroed_page(GFP_KERNEL);
166 if (!page)
167 return -ENOMEM;
168
169 info->xmit.buf = (unsigned char *) page;
170 uart_circ_clear(&info->xmit);
171 }
172
173 retval = port->ops->startup(port);
174 if (retval == 0) {
175 if (init_hw) {
176 /*
177 * Initialise the hardware port settings.
178 */
179 uart_change_speed(state, NULL);
180
181 /*
182 * Setup the RTS and DTR signals once the
183 * port is open and ready to respond.
184 */
185 if (info->tty->termios->c_cflag & CBAUD)
186 uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
187 }
188
Russell King0dd7a1a2005-06-29 18:40:53 +0100189 if (info->flags & UIF_CTS_FLOW) {
190 spin_lock_irq(&port->lock);
191 if (!(port->ops->get_mctrl(port) & TIOCM_CTS))
192 info->tty->hw_stopped = 1;
193 spin_unlock_irq(&port->lock);
194 }
195
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 info->flags |= UIF_INITIALIZED;
197
198 clear_bit(TTY_IO_ERROR, &info->tty->flags);
199 }
200
201 if (retval && capable(CAP_SYS_ADMIN))
202 retval = 0;
203
204 return retval;
205}
206
207/*
208 * This routine will shutdown a serial port; interrupts are disabled, and
209 * DTR is dropped if the hangup on close termio flag is on. Calls to
210 * uart_shutdown are serialised by the per-port semaphore.
211 */
212static void uart_shutdown(struct uart_state *state)
213{
214 struct uart_info *info = state->info;
215 struct uart_port *port = state->port;
216
Russell Kingee31b332005-11-13 15:28:51 +0000217 /*
218 * Set the TTY IO error marker
219 */
220 if (info->tty)
221 set_bit(TTY_IO_ERROR, &info->tty->flags);
222
223 if (info->flags & UIF_INITIALIZED) {
224 info->flags &= ~UIF_INITIALIZED;
225
226 /*
227 * Turn off DTR and RTS early.
228 */
229 if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
230 uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
231
232 /*
233 * clear delta_msr_wait queue to avoid mem leaks: we may free
234 * the irq here so the queue might never be woken up. Note
235 * that we won't end up waiting on delta_msr_wait again since
236 * any outstanding file descriptors should be pointing at
237 * hung_up_tty_fops now.
238 */
239 wake_up_interruptible(&info->delta_msr_wait);
240
241 /*
242 * Free the IRQ and disable the port.
243 */
244 port->ops->shutdown(port);
245
246 /*
247 * Ensure that the IRQ handler isn't running on another CPU.
248 */
249 synchronize_irq(port->irq);
250 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251
252 /*
Russell Kingee31b332005-11-13 15:28:51 +0000253 * kill off our tasklet
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 */
Russell Kingee31b332005-11-13 15:28:51 +0000255 tasklet_kill(&info->tlet);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
257 /*
258 * Free the transmit buffer page.
259 */
260 if (info->xmit.buf) {
261 free_page((unsigned long)info->xmit.buf);
262 info->xmit.buf = NULL;
263 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264}
265
266/**
267 * uart_update_timeout - update per-port FIFO timeout.
268 * @port: uart_port structure describing the port
269 * @cflag: termios cflag value
270 * @baud: speed of the port
271 *
272 * Set the port FIFO timeout value. The @cflag value should
273 * reflect the actual hardware settings.
274 */
275void
276uart_update_timeout(struct uart_port *port, unsigned int cflag,
277 unsigned int baud)
278{
279 unsigned int bits;
280
281 /* byte size and parity */
282 switch (cflag & CSIZE) {
283 case CS5:
284 bits = 7;
285 break;
286 case CS6:
287 bits = 8;
288 break;
289 case CS7:
290 bits = 9;
291 break;
292 default:
293 bits = 10;
Alan Coxa46c9992008-02-08 04:18:53 -0800294 break; /* CS8 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 }
296
297 if (cflag & CSTOPB)
298 bits++;
299 if (cflag & PARENB)
300 bits++;
301
302 /*
303 * The total number of bits to be transmitted in the fifo.
304 */
305 bits = bits * port->fifosize;
306
307 /*
308 * Figure the timeout to send the above number of bits.
309 * Add .02 seconds of slop
310 */
311 port->timeout = (HZ * bits) / baud + HZ/50;
312}
313
314EXPORT_SYMBOL(uart_update_timeout);
315
316/**
317 * uart_get_baud_rate - return baud rate for a particular port
318 * @port: uart_port structure describing the port in question.
319 * @termios: desired termios settings.
320 * @old: old termios (or NULL)
321 * @min: minimum acceptable baud rate
322 * @max: maximum acceptable baud rate
323 *
324 * Decode the termios structure into a numeric baud rate,
325 * taking account of the magic 38400 baud rate (with spd_*
326 * flags), and mapping the %B0 rate to 9600 baud.
327 *
328 * If the new baud rate is invalid, try the old termios setting.
329 * If it's still invalid, we try 9600 baud.
330 *
331 * Update the @termios structure to reflect the baud rate
Alan Coxeb424fd2008-04-28 02:14:07 -0700332 * we're actually going to be using. Don't do this for the case
333 * where B0 is requested ("hang up").
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 */
335unsigned int
Alan Cox606d0992006-12-08 02:38:45 -0800336uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
337 struct ktermios *old, unsigned int min, unsigned int max)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338{
339 unsigned int try, baud, altbaud = 38400;
Alan Coxeb424fd2008-04-28 02:14:07 -0700340 int hung_up = 0;
Russell King0077d452006-01-21 23:03:28 +0000341 upf_t flags = port->flags & UPF_SPD_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342
343 if (flags == UPF_SPD_HI)
344 altbaud = 57600;
345 if (flags == UPF_SPD_VHI)
346 altbaud = 115200;
347 if (flags == UPF_SPD_SHI)
348 altbaud = 230400;
349 if (flags == UPF_SPD_WARP)
350 altbaud = 460800;
351
352 for (try = 0; try < 2; try++) {
353 baud = tty_termios_baud_rate(termios);
354
355 /*
356 * The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
357 * Die! Die! Die!
358 */
359 if (baud == 38400)
360 baud = altbaud;
361
362 /*
363 * Special case: B0 rate.
364 */
Alan Coxeb424fd2008-04-28 02:14:07 -0700365 if (baud == 0) {
366 hung_up = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 baud = 9600;
Alan Coxeb424fd2008-04-28 02:14:07 -0700368 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
370 if (baud >= min && baud <= max)
371 return baud;
372
373 /*
374 * Oops, the quotient was zero. Try again with
375 * the old baud rate if possible.
376 */
377 termios->c_cflag &= ~CBAUD;
378 if (old) {
Alan Cox6d4d67b2008-02-04 22:27:53 -0800379 baud = tty_termios_baud_rate(old);
Alan Coxeb424fd2008-04-28 02:14:07 -0700380 if (!hung_up)
381 tty_termios_encode_baud_rate(termios,
382 baud, baud);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 old = NULL;
384 continue;
385 }
386
387 /*
388 * As a last resort, if the quotient is zero,
389 * default to 9600 bps
390 */
Alan Coxeb424fd2008-04-28 02:14:07 -0700391 if (!hung_up)
392 tty_termios_encode_baud_rate(termios, 9600, 9600);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 }
394
395 return 0;
396}
397
398EXPORT_SYMBOL(uart_get_baud_rate);
399
400/**
401 * uart_get_divisor - return uart clock divisor
402 * @port: uart_port structure describing the port.
403 * @baud: desired baud rate
404 *
405 * Calculate the uart clock divisor for the port.
406 */
407unsigned int
408uart_get_divisor(struct uart_port *port, unsigned int baud)
409{
410 unsigned int quot;
411
412 /*
413 * Old custom speed handling.
414 */
415 if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
416 quot = port->custom_divisor;
417 else
418 quot = (port->uartclk + (8 * baud)) / (16 * baud);
419
420 return quot;
421}
422
423EXPORT_SYMBOL(uart_get_divisor);
424
Alan Cox23d22ce2008-04-30 00:54:11 -0700425/* FIXME: Consistent locking policy */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426static void
Alan Cox606d0992006-12-08 02:38:45 -0800427uart_change_speed(struct uart_state *state, struct ktermios *old_termios)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428{
429 struct tty_struct *tty = state->info->tty;
430 struct uart_port *port = state->port;
Alan Cox606d0992006-12-08 02:38:45 -0800431 struct ktermios *termios;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432
433 /*
434 * If we have no tty, termios, or the port does not exist,
435 * then we can't set the parameters for this port.
436 */
437 if (!tty || !tty->termios || port->type == PORT_UNKNOWN)
438 return;
439
440 termios = tty->termios;
441
442 /*
443 * Set flags based on termios cflag
444 */
445 if (termios->c_cflag & CRTSCTS)
446 state->info->flags |= UIF_CTS_FLOW;
447 else
448 state->info->flags &= ~UIF_CTS_FLOW;
449
450 if (termios->c_cflag & CLOCAL)
451 state->info->flags &= ~UIF_CHECK_CD;
452 else
453 state->info->flags |= UIF_CHECK_CD;
454
455 port->ops->set_termios(port, termios, old_termios);
456}
457
Alan Cox23d22ce2008-04-30 00:54:11 -0700458static inline int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459__uart_put_char(struct uart_port *port, struct circ_buf *circ, unsigned char c)
460{
461 unsigned long flags;
Alan Cox23d22ce2008-04-30 00:54:11 -0700462 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463
464 if (!circ->buf)
Alan Cox23d22ce2008-04-30 00:54:11 -0700465 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466
467 spin_lock_irqsave(&port->lock, flags);
468 if (uart_circ_chars_free(circ) != 0) {
469 circ->buf[circ->head] = c;
470 circ->head = (circ->head + 1) & (UART_XMIT_SIZE - 1);
Alan Cox23d22ce2008-04-30 00:54:11 -0700471 ret = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 }
473 spin_unlock_irqrestore(&port->lock, flags);
Alan Cox23d22ce2008-04-30 00:54:11 -0700474 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475}
476
Alan Cox23d22ce2008-04-30 00:54:11 -0700477static int uart_put_char(struct tty_struct *tty, unsigned char ch)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478{
479 struct uart_state *state = tty->driver_data;
480
Alan Cox23d22ce2008-04-30 00:54:11 -0700481 return __uart_put_char(state->port, &state->info->xmit, ch);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482}
483
484static void uart_flush_chars(struct tty_struct *tty)
485{
486 uart_start(tty);
487}
488
489static int
Pavel Machekd5f735e2006-03-07 21:55:20 -0800490uart_write(struct tty_struct *tty, const unsigned char *buf, int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491{
492 struct uart_state *state = tty->driver_data;
Pavel Machekd5f735e2006-03-07 21:55:20 -0800493 struct uart_port *port;
494 struct circ_buf *circ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 unsigned long flags;
496 int c, ret = 0;
497
Pavel Machekd5f735e2006-03-07 21:55:20 -0800498 /*
499 * This means you called this function _after_ the port was
500 * closed. No cookie for you.
501 */
502 if (!state || !state->info) {
503 WARN_ON(1);
504 return -EL3HLT;
505 }
506
507 port = state->port;
508 circ = &state->info->xmit;
509
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 if (!circ->buf)
511 return 0;
512
513 spin_lock_irqsave(&port->lock, flags);
514 while (1) {
515 c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE);
516 if (count < c)
517 c = count;
518 if (c <= 0)
519 break;
520 memcpy(circ->buf + circ->head, buf, c);
521 circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1);
522 buf += c;
523 count -= c;
524 ret += c;
525 }
526 spin_unlock_irqrestore(&port->lock, flags);
527
528 uart_start(tty);
529 return ret;
530}
531
532static int uart_write_room(struct tty_struct *tty)
533{
534 struct uart_state *state = tty->driver_data;
Alan Coxf34d7a52008-04-30 00:54:13 -0700535 unsigned long flags;
536 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537
Alan Coxf34d7a52008-04-30 00:54:13 -0700538 spin_lock_irqsave(&state->port->lock, flags);
539 ret = uart_circ_chars_free(&state->info->xmit);
540 spin_unlock_irqrestore(&state->port->lock, flags);
541 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542}
543
544static int uart_chars_in_buffer(struct tty_struct *tty)
545{
546 struct uart_state *state = tty->driver_data;
Alan Coxf34d7a52008-04-30 00:54:13 -0700547 unsigned long flags;
548 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549
Alan Coxf34d7a52008-04-30 00:54:13 -0700550 spin_lock_irqsave(&state->port->lock, flags);
551 ret = uart_circ_chars_pending(&state->info->xmit);
552 spin_unlock_irqrestore(&state->port->lock, flags);
553 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554}
555
556static void uart_flush_buffer(struct tty_struct *tty)
557{
558 struct uart_state *state = tty->driver_data;
Tetsuo Handa55d7b682008-05-06 20:42:27 -0700559 struct uart_port *port;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 unsigned long flags;
561
Pavel Machekd5f735e2006-03-07 21:55:20 -0800562 /*
563 * This means you called this function _after_ the port was
564 * closed. No cookie for you.
565 */
566 if (!state || !state->info) {
567 WARN_ON(1);
568 return;
569 }
570
Tetsuo Handa55d7b682008-05-06 20:42:27 -0700571 port = state->port;
Jiri Slabyeb3a1e12007-05-06 14:48:52 -0700572 pr_debug("uart_flush_buffer(%d) called\n", tty->index);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
574 spin_lock_irqsave(&port->lock, flags);
575 uart_circ_clear(&state->info->xmit);
576 spin_unlock_irqrestore(&port->lock, flags);
577 tty_wakeup(tty);
578}
579
580/*
581 * This function is used to send a high-priority XON/XOFF character to
582 * the device
583 */
584static void uart_send_xchar(struct tty_struct *tty, char ch)
585{
586 struct uart_state *state = tty->driver_data;
587 struct uart_port *port = state->port;
588 unsigned long flags;
589
590 if (port->ops->send_xchar)
591 port->ops->send_xchar(port, ch);
592 else {
593 port->x_char = ch;
594 if (ch) {
595 spin_lock_irqsave(&port->lock, flags);
Russell Kingb129a8c2005-08-31 10:12:14 +0100596 port->ops->start_tx(port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 spin_unlock_irqrestore(&port->lock, flags);
598 }
599 }
600}
601
602static void uart_throttle(struct tty_struct *tty)
603{
604 struct uart_state *state = tty->driver_data;
605
606 if (I_IXOFF(tty))
607 uart_send_xchar(tty, STOP_CHAR(tty));
608
609 if (tty->termios->c_cflag & CRTSCTS)
610 uart_clear_mctrl(state->port, TIOCM_RTS);
611}
612
613static void uart_unthrottle(struct tty_struct *tty)
614{
615 struct uart_state *state = tty->driver_data;
616 struct uart_port *port = state->port;
617
618 if (I_IXOFF(tty)) {
619 if (port->x_char)
620 port->x_char = 0;
621 else
622 uart_send_xchar(tty, START_CHAR(tty));
623 }
624
625 if (tty->termios->c_cflag & CRTSCTS)
626 uart_set_mctrl(port, TIOCM_RTS);
627}
628
629static int uart_get_info(struct uart_state *state,
630 struct serial_struct __user *retinfo)
631{
632 struct uart_port *port = state->port;
633 struct serial_struct tmp;
634
635 memset(&tmp, 0, sizeof(tmp));
Alan Coxf34d7a52008-04-30 00:54:13 -0700636
637 /* Ensure the state we copy is consistent and no hardware changes
638 occur as we go */
639 mutex_lock(&state->mutex);
640
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 tmp.type = port->type;
642 tmp.line = port->line;
643 tmp.port = port->iobase;
644 if (HIGH_BITS_OFFSET)
645 tmp.port_high = (long) port->iobase >> HIGH_BITS_OFFSET;
646 tmp.irq = port->irq;
647 tmp.flags = port->flags;
648 tmp.xmit_fifo_size = port->fifosize;
649 tmp.baud_base = port->uartclk / 16;
650 tmp.close_delay = state->close_delay / 10;
651 tmp.closing_wait = state->closing_wait == USF_CLOSING_WAIT_NONE ?
652 ASYNC_CLOSING_WAIT_NONE :
Alan Coxa46c9992008-02-08 04:18:53 -0800653 state->closing_wait / 10;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 tmp.custom_divisor = port->custom_divisor;
655 tmp.hub6 = port->hub6;
656 tmp.io_type = port->iotype;
657 tmp.iomem_reg_shift = port->regshift;
Josh Boyer4f640ef2007-07-23 18:43:44 -0700658 tmp.iomem_base = (void *)(unsigned long)port->mapbase;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659
Alan Coxf34d7a52008-04-30 00:54:13 -0700660 mutex_unlock(&state->mutex);
661
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
663 return -EFAULT;
664 return 0;
665}
666
667static int uart_set_info(struct uart_state *state,
668 struct serial_struct __user *newinfo)
669{
670 struct serial_struct new_serial;
671 struct uart_port *port = state->port;
672 unsigned long new_port;
Russell King0077d452006-01-21 23:03:28 +0000673 unsigned int change_irq, change_port, closing_wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 unsigned int old_custom_divisor, close_delay;
Russell King0077d452006-01-21 23:03:28 +0000675 upf_t old_flags, new_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 int retval = 0;
677
678 if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
679 return -EFAULT;
680
681 new_port = new_serial.port;
682 if (HIGH_BITS_OFFSET)
683 new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET;
684
685 new_serial.irq = irq_canonicalize(new_serial.irq);
686 close_delay = new_serial.close_delay * 10;
687 closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
688 USF_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
689
690 /*
691 * This semaphore protects state->count. It is also
692 * very useful to prevent opens. Also, take the
693 * port configuration semaphore to make sure that a
694 * module insertion/removal doesn't change anything
695 * under us.
696 */
Ingo Molnare2862f62006-01-13 21:37:07 +0000697 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698
David Gibsonabb4a232007-05-06 14:48:49 -0700699 change_irq = !(port->flags & UPF_FIXED_PORT)
700 && new_serial.irq != port->irq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701
702 /*
703 * Since changing the 'type' of the port changes its resource
704 * allocations, we should treat type changes the same as
705 * IO port changes.
706 */
David Gibsonabb4a232007-05-06 14:48:49 -0700707 change_port = !(port->flags & UPF_FIXED_PORT)
708 && (new_port != port->iobase ||
709 (unsigned long)new_serial.iomem_base != port->mapbase ||
710 new_serial.hub6 != port->hub6 ||
711 new_serial.io_type != port->iotype ||
712 new_serial.iomem_reg_shift != port->regshift ||
713 new_serial.type != port->type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714
715 old_flags = port->flags;
Russell King0077d452006-01-21 23:03:28 +0000716 new_flags = new_serial.flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 old_custom_divisor = port->custom_divisor;
718
719 if (!capable(CAP_SYS_ADMIN)) {
720 retval = -EPERM;
721 if (change_irq || change_port ||
722 (new_serial.baud_base != port->uartclk / 16) ||
723 (close_delay != state->close_delay) ||
724 (closing_wait != state->closing_wait) ||
Russell King947deee2006-07-02 20:45:51 +0100725 (new_serial.xmit_fifo_size &&
726 new_serial.xmit_fifo_size != port->fifosize) ||
Russell King0077d452006-01-21 23:03:28 +0000727 (((new_flags ^ old_flags) & ~UPF_USR_MASK) != 0))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 goto exit;
729 port->flags = ((port->flags & ~UPF_USR_MASK) |
Russell King0077d452006-01-21 23:03:28 +0000730 (new_flags & UPF_USR_MASK));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 port->custom_divisor = new_serial.custom_divisor;
732 goto check_and_exit;
733 }
734
735 /*
736 * Ask the low level driver to verify the settings.
737 */
738 if (port->ops->verify_port)
739 retval = port->ops->verify_port(port, &new_serial);
740
741 if ((new_serial.irq >= NR_IRQS) || (new_serial.irq < 0) ||
742 (new_serial.baud_base < 9600))
743 retval = -EINVAL;
744
745 if (retval)
746 goto exit;
747
748 if (change_port || change_irq) {
749 retval = -EBUSY;
750
751 /*
752 * Make sure that we are the sole user of this port.
753 */
754 if (uart_users(state) > 1)
755 goto exit;
756
757 /*
758 * We need to shutdown the serial port at the old
759 * port/type/irq combination.
760 */
761 uart_shutdown(state);
762 }
763
764 if (change_port) {
765 unsigned long old_iobase, old_mapbase;
766 unsigned int old_type, old_iotype, old_hub6, old_shift;
767
768 old_iobase = port->iobase;
769 old_mapbase = port->mapbase;
770 old_type = port->type;
771 old_hub6 = port->hub6;
772 old_iotype = port->iotype;
773 old_shift = port->regshift;
774
775 /*
776 * Free and release old regions
777 */
778 if (old_type != PORT_UNKNOWN)
779 port->ops->release_port(port);
780
781 port->iobase = new_port;
782 port->type = new_serial.type;
783 port->hub6 = new_serial.hub6;
784 port->iotype = new_serial.io_type;
785 port->regshift = new_serial.iomem_reg_shift;
786 port->mapbase = (unsigned long)new_serial.iomem_base;
787
788 /*
789 * Claim and map the new regions
790 */
791 if (port->type != PORT_UNKNOWN) {
792 retval = port->ops->request_port(port);
793 } else {
794 /* Always success - Jean II */
795 retval = 0;
796 }
797
798 /*
799 * If we fail to request resources for the
800 * new port, try to restore the old settings.
801 */
802 if (retval && old_type != PORT_UNKNOWN) {
803 port->iobase = old_iobase;
804 port->type = old_type;
805 port->hub6 = old_hub6;
806 port->iotype = old_iotype;
807 port->regshift = old_shift;
808 port->mapbase = old_mapbase;
809 retval = port->ops->request_port(port);
810 /*
811 * If we failed to restore the old settings,
812 * we fail like this.
813 */
814 if (retval)
815 port->type = PORT_UNKNOWN;
816
817 /*
818 * We failed anyway.
819 */
820 retval = -EBUSY;
Alan Coxa46c9992008-02-08 04:18:53 -0800821 /* Added to return the correct error -Ram Gupta */
822 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823 }
824 }
825
David Gibsonabb4a232007-05-06 14:48:49 -0700826 if (change_irq)
827 port->irq = new_serial.irq;
828 if (!(port->flags & UPF_FIXED_PORT))
829 port->uartclk = new_serial.baud_base * 16;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 port->flags = (port->flags & ~UPF_CHANGE_MASK) |
Russell King0077d452006-01-21 23:03:28 +0000831 (new_flags & UPF_CHANGE_MASK);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 port->custom_divisor = new_serial.custom_divisor;
833 state->close_delay = close_delay;
834 state->closing_wait = closing_wait;
Russell King947deee2006-07-02 20:45:51 +0100835 if (new_serial.xmit_fifo_size)
836 port->fifosize = new_serial.xmit_fifo_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 if (state->info->tty)
838 state->info->tty->low_latency =
839 (port->flags & UPF_LOW_LATENCY) ? 1 : 0;
840
841 check_and_exit:
842 retval = 0;
843 if (port->type == PORT_UNKNOWN)
844 goto exit;
845 if (state->info->flags & UIF_INITIALIZED) {
846 if (((old_flags ^ port->flags) & UPF_SPD_MASK) ||
847 old_custom_divisor != port->custom_divisor) {
848 /*
849 * If they're setting up a custom divisor or speed,
850 * instead of clearing it, then bitch about it. No
851 * need to rate-limit; it's CAP_SYS_ADMIN only.
852 */
853 if (port->flags & UPF_SPD_MASK) {
854 char buf[64];
855 printk(KERN_NOTICE
856 "%s sets custom speed on %s. This "
857 "is deprecated.\n", current->comm,
858 tty_name(state->info->tty, buf));
859 }
860 uart_change_speed(state, NULL);
861 }
862 } else
863 retval = uart_startup(state, 1);
864 exit:
Ingo Molnare2862f62006-01-13 21:37:07 +0000865 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 return retval;
867}
868
869
870/*
871 * uart_get_lsr_info - get line status register info.
872 * Note: uart_ioctl protects us against hangups.
873 */
874static int uart_get_lsr_info(struct uart_state *state,
875 unsigned int __user *value)
876{
877 struct uart_port *port = state->port;
878 unsigned int result;
879
880 result = port->ops->tx_empty(port);
881
882 /*
883 * If we're about to load something into the transmit
884 * register, we'll pretend the transmitter isn't empty to
885 * avoid a race condition (depending on when the transmit
886 * interrupt happens).
887 */
888 if (port->x_char ||
889 ((uart_circ_chars_pending(&state->info->xmit) > 0) &&
890 !state->info->tty->stopped && !state->info->tty->hw_stopped))
891 result &= ~TIOCSER_TEMT;
Alan Coxa46c9992008-02-08 04:18:53 -0800892
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 return put_user(result, value);
894}
895
896static int uart_tiocmget(struct tty_struct *tty, struct file *file)
897{
898 struct uart_state *state = tty->driver_data;
899 struct uart_port *port = state->port;
900 int result = -EIO;
901
Ingo Molnare2862f62006-01-13 21:37:07 +0000902 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903 if ((!file || !tty_hung_up_p(file)) &&
904 !(tty->flags & (1 << TTY_IO_ERROR))) {
905 result = port->mctrl;
Russell Kingc5f46442005-06-29 09:42:38 +0100906
907 spin_lock_irq(&port->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 result |= port->ops->get_mctrl(port);
Russell Kingc5f46442005-06-29 09:42:38 +0100909 spin_unlock_irq(&port->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910 }
Ingo Molnare2862f62006-01-13 21:37:07 +0000911 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912
913 return result;
914}
915
916static int
917uart_tiocmset(struct tty_struct *tty, struct file *file,
918 unsigned int set, unsigned int clear)
919{
920 struct uart_state *state = tty->driver_data;
921 struct uart_port *port = state->port;
922 int ret = -EIO;
923
Ingo Molnare2862f62006-01-13 21:37:07 +0000924 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 if ((!file || !tty_hung_up_p(file)) &&
926 !(tty->flags & (1 << TTY_IO_ERROR))) {
927 uart_update_mctrl(port, set, clear);
928 ret = 0;
929 }
Ingo Molnare2862f62006-01-13 21:37:07 +0000930 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 return ret;
932}
933
934static void uart_break_ctl(struct tty_struct *tty, int break_state)
935{
936 struct uart_state *state = tty->driver_data;
937 struct uart_port *port = state->port;
938
Ingo Molnare2862f62006-01-13 21:37:07 +0000939 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940
941 if (port->type != PORT_UNKNOWN)
942 port->ops->break_ctl(port, break_state);
943
Ingo Molnare2862f62006-01-13 21:37:07 +0000944 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945}
946
947static int uart_do_autoconfig(struct uart_state *state)
948{
949 struct uart_port *port = state->port;
950 int flags, ret;
951
952 if (!capable(CAP_SYS_ADMIN))
953 return -EPERM;
954
955 /*
956 * Take the per-port semaphore. This prevents count from
957 * changing, and hence any extra opens of the port while
958 * we're auto-configuring.
959 */
Ingo Molnare2862f62006-01-13 21:37:07 +0000960 if (mutex_lock_interruptible(&state->mutex))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961 return -ERESTARTSYS;
962
963 ret = -EBUSY;
964 if (uart_users(state) == 1) {
965 uart_shutdown(state);
966
967 /*
968 * If we already have a port type configured,
969 * we must release its resources.
970 */
971 if (port->type != PORT_UNKNOWN)
972 port->ops->release_port(port);
973
974 flags = UART_CONFIG_TYPE;
975 if (port->flags & UPF_AUTO_IRQ)
976 flags |= UART_CONFIG_IRQ;
977
978 /*
979 * This will claim the ports resources if
980 * a port is found.
981 */
982 port->ops->config_port(port, flags);
983
984 ret = uart_startup(state, 1);
985 }
Ingo Molnare2862f62006-01-13 21:37:07 +0000986 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987 return ret;
988}
989
990/*
991 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
992 * - mask passed in arg for lines of interest
993 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
994 * Caller should use TIOCGICOUNT to see which one it was
995 */
996static int
997uart_wait_modem_status(struct uart_state *state, unsigned long arg)
998{
999 struct uart_port *port = state->port;
1000 DECLARE_WAITQUEUE(wait, current);
1001 struct uart_icount cprev, cnow;
1002 int ret;
1003
1004 /*
1005 * note the counters on entry
1006 */
1007 spin_lock_irq(&port->lock);
1008 memcpy(&cprev, &port->icount, sizeof(struct uart_icount));
1009
1010 /*
1011 * Force modem status interrupts on
1012 */
1013 port->ops->enable_ms(port);
1014 spin_unlock_irq(&port->lock);
1015
1016 add_wait_queue(&state->info->delta_msr_wait, &wait);
1017 for (;;) {
1018 spin_lock_irq(&port->lock);
1019 memcpy(&cnow, &port->icount, sizeof(struct uart_icount));
1020 spin_unlock_irq(&port->lock);
1021
1022 set_current_state(TASK_INTERRUPTIBLE);
1023
1024 if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1025 ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1026 ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
1027 ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
Alan Coxa46c9992008-02-08 04:18:53 -08001028 ret = 0;
1029 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030 }
1031
1032 schedule();
1033
1034 /* see if a signal did it */
1035 if (signal_pending(current)) {
1036 ret = -ERESTARTSYS;
1037 break;
1038 }
1039
1040 cprev = cnow;
1041 }
1042
1043 current->state = TASK_RUNNING;
1044 remove_wait_queue(&state->info->delta_msr_wait, &wait);
1045
1046 return ret;
1047}
1048
1049/*
1050 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1051 * Return: write counters to the user passed counter struct
1052 * NB: both 1->0 and 0->1 transitions are counted except for
1053 * RI where only 0->1 is counted.
1054 */
1055static int uart_get_count(struct uart_state *state,
1056 struct serial_icounter_struct __user *icnt)
1057{
1058 struct serial_icounter_struct icount;
1059 struct uart_icount cnow;
1060 struct uart_port *port = state->port;
1061
1062 spin_lock_irq(&port->lock);
1063 memcpy(&cnow, &port->icount, sizeof(struct uart_icount));
1064 spin_unlock_irq(&port->lock);
1065
1066 icount.cts = cnow.cts;
1067 icount.dsr = cnow.dsr;
1068 icount.rng = cnow.rng;
1069 icount.dcd = cnow.dcd;
1070 icount.rx = cnow.rx;
1071 icount.tx = cnow.tx;
1072 icount.frame = cnow.frame;
1073 icount.overrun = cnow.overrun;
1074 icount.parity = cnow.parity;
1075 icount.brk = cnow.brk;
1076 icount.buf_overrun = cnow.buf_overrun;
1077
1078 return copy_to_user(icnt, &icount, sizeof(icount)) ? -EFAULT : 0;
1079}
1080
1081/*
Alan Coxe5238442008-04-30 00:53:28 -07001082 * Called via sys_ioctl. We can use spin_lock_irq() here.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083 */
1084static int
1085uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
1086 unsigned long arg)
1087{
1088 struct uart_state *state = tty->driver_data;
1089 void __user *uarg = (void __user *)arg;
1090 int ret = -ENOIOCTLCMD;
1091
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092
1093 /*
1094 * These ioctls don't rely on the hardware to be present.
1095 */
1096 switch (cmd) {
1097 case TIOCGSERIAL:
1098 ret = uart_get_info(state, uarg);
1099 break;
1100
1101 case TIOCSSERIAL:
1102 ret = uart_set_info(state, uarg);
1103 break;
1104
1105 case TIOCSERCONFIG:
1106 ret = uart_do_autoconfig(state);
1107 break;
1108
1109 case TIOCSERGWILD: /* obsolete */
1110 case TIOCSERSWILD: /* obsolete */
1111 ret = 0;
1112 break;
1113 }
1114
1115 if (ret != -ENOIOCTLCMD)
1116 goto out;
1117
1118 if (tty->flags & (1 << TTY_IO_ERROR)) {
1119 ret = -EIO;
1120 goto out;
1121 }
1122
1123 /*
1124 * The following should only be used when hardware is present.
1125 */
1126 switch (cmd) {
1127 case TIOCMIWAIT:
1128 ret = uart_wait_modem_status(state, arg);
1129 break;
1130
1131 case TIOCGICOUNT:
1132 ret = uart_get_count(state, uarg);
1133 break;
1134 }
1135
1136 if (ret != -ENOIOCTLCMD)
1137 goto out;
1138
Ingo Molnare2862f62006-01-13 21:37:07 +00001139 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140
1141 if (tty_hung_up_p(filp)) {
1142 ret = -EIO;
1143 goto out_up;
1144 }
1145
1146 /*
1147 * All these rely on hardware being present and need to be
1148 * protected against the tty being hung up.
1149 */
1150 switch (cmd) {
1151 case TIOCSERGETLSR: /* Get line status register */
1152 ret = uart_get_lsr_info(state, uarg);
1153 break;
1154
1155 default: {
1156 struct uart_port *port = state->port;
1157 if (port->ops->ioctl)
1158 ret = port->ops->ioctl(port, cmd, arg);
1159 break;
1160 }
1161 }
Alan Coxf34d7a52008-04-30 00:54:13 -07001162out_up:
Ingo Molnare2862f62006-01-13 21:37:07 +00001163 mutex_unlock(&state->mutex);
Alan Coxf34d7a52008-04-30 00:54:13 -07001164out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165 return ret;
1166}
1167
Linus Torvaldsedeb2802008-06-04 10:35:03 -07001168static void uart_set_ldisc(struct tty_struct *tty)
Alan Cox64e91592008-06-03 15:18:54 +01001169{
1170 struct uart_state *state = tty->driver_data;
1171 struct uart_port *port = state->port;
1172
1173 if (port->ops->set_ldisc)
1174 port->ops->set_ldisc(port);
1175}
1176
Alan Coxa46c9992008-02-08 04:18:53 -08001177static void uart_set_termios(struct tty_struct *tty,
1178 struct ktermios *old_termios)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001179{
1180 struct uart_state *state = tty->driver_data;
1181 unsigned long flags;
1182 unsigned int cflag = tty->termios->c_cflag;
1183
Linus Torvalds1da177e2005-04-16 15:20:36 -07001184
1185 /*
1186 * These are the bits that are used to setup various
David Woodhouse20620d62007-08-22 14:01:11 -07001187 * flags in the low level driver. We can ignore the Bfoo
1188 * bits in c_cflag; c_[io]speed will always be set
1189 * appropriately by set_termios() in tty_ioctl.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07001190 */
1191#define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192 if ((cflag ^ old_termios->c_cflag) == 0 &&
David Woodhouse20620d62007-08-22 14:01:11 -07001193 tty->termios->c_ospeed == old_termios->c_ospeed &&
1194 tty->termios->c_ispeed == old_termios->c_ispeed &&
Alan Coxe5238442008-04-30 00:53:28 -07001195 RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196 return;
Alan Coxe5238442008-04-30 00:53:28 -07001197 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001198
1199 uart_change_speed(state, old_termios);
1200
1201 /* Handle transition to B0 status */
1202 if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD))
1203 uart_clear_mctrl(state->port, TIOCM_RTS | TIOCM_DTR);
1204
1205 /* Handle transition away from B0 status */
1206 if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
1207 unsigned int mask = TIOCM_DTR;
1208 if (!(cflag & CRTSCTS) ||
1209 !test_bit(TTY_THROTTLED, &tty->flags))
1210 mask |= TIOCM_RTS;
1211 uart_set_mctrl(state->port, mask);
1212 }
1213
1214 /* Handle turning off CRTSCTS */
1215 if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {
1216 spin_lock_irqsave(&state->port->lock, flags);
1217 tty->hw_stopped = 0;
1218 __uart_start(tty);
1219 spin_unlock_irqrestore(&state->port->lock, flags);
1220 }
1221
Russell King0dd7a1a2005-06-29 18:40:53 +01001222 /* Handle turning on CRTSCTS */
1223 if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
1224 spin_lock_irqsave(&state->port->lock, flags);
1225 if (!(state->port->ops->get_mctrl(state->port) & TIOCM_CTS)) {
1226 tty->hw_stopped = 1;
Russell Kingb129a8c2005-08-31 10:12:14 +01001227 state->port->ops->stop_tx(state->port);
Russell King0dd7a1a2005-06-29 18:40:53 +01001228 }
1229 spin_unlock_irqrestore(&state->port->lock, flags);
1230 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231#if 0
1232 /*
1233 * No need to wake up processes in open wait, since they
1234 * sample the CLOCAL flag once, and don't recheck it.
1235 * XXX It's not clear whether the current behavior is correct
1236 * or not. Hence, this may change.....
1237 */
1238 if (!(old_termios->c_cflag & CLOCAL) &&
1239 (tty->termios->c_cflag & CLOCAL))
1240 wake_up_interruptible(&state->info->open_wait);
1241#endif
1242}
1243
1244/*
1245 * In 2.4.5, calls to this will be serialized via the BKL in
1246 * linux/drivers/char/tty_io.c:tty_release()
1247 * linux/drivers/char/tty_io.c:do_tty_handup()
1248 */
1249static void uart_close(struct tty_struct *tty, struct file *filp)
1250{
1251 struct uart_state *state = tty->driver_data;
1252 struct uart_port *port;
Alan Coxa46c9992008-02-08 04:18:53 -08001253
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254 BUG_ON(!kernel_locked());
1255
1256 if (!state || !state->port)
1257 return;
1258
1259 port = state->port;
1260
Jiri Slabyeb3a1e12007-05-06 14:48:52 -07001261 pr_debug("uart_close(%d) called\n", port->line);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262
Ingo Molnare2862f62006-01-13 21:37:07 +00001263 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001264
1265 if (tty_hung_up_p(filp))
1266 goto done;
1267
1268 if ((tty->count == 1) && (state->count != 1)) {
1269 /*
1270 * Uh, oh. tty->count is 1, which means that the tty
1271 * structure will be freed. state->count should always
1272 * be one in these conditions. If it's greater than
1273 * one, we've got real problems, since it means the
1274 * serial port won't be shutdown.
1275 */
1276 printk(KERN_ERR "uart_close: bad serial port count; tty->count is 1, "
1277 "state->count is %d\n", state->count);
1278 state->count = 1;
1279 }
1280 if (--state->count < 0) {
1281 printk(KERN_ERR "uart_close: bad serial port count for %s: %d\n",
1282 tty->name, state->count);
1283 state->count = 0;
1284 }
1285 if (state->count)
1286 goto done;
1287
1288 /*
1289 * Now we wait for the transmit buffer to clear; and we notify
1290 * the line discipline to only process XON/XOFF characters by
1291 * setting tty->closing.
1292 */
1293 tty->closing = 1;
1294
1295 if (state->closing_wait != USF_CLOSING_WAIT_NONE)
1296 tty_wait_until_sent(tty, msecs_to_jiffies(state->closing_wait));
1297
1298 /*
1299 * At this point, we stop accepting input. To do this, we
1300 * disable the receive line status interrupts.
1301 */
1302 if (state->info->flags & UIF_INITIALIZED) {
1303 unsigned long flags;
1304 spin_lock_irqsave(&port->lock, flags);
1305 port->ops->stop_rx(port);
1306 spin_unlock_irqrestore(&port->lock, flags);
1307 /*
1308 * Before we drop DTR, make sure the UART transmitter
1309 * has completely drained; this is especially
1310 * important if there is a transmit FIFO!
1311 */
1312 uart_wait_until_sent(tty, port->timeout);
1313 }
1314
1315 uart_shutdown(state);
1316 uart_flush_buffer(tty);
1317
Alan Coxa46c9992008-02-08 04:18:53 -08001318 tty_ldisc_flush(tty);
1319
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320 tty->closing = 0;
1321 state->info->tty = NULL;
1322
1323 if (state->info->blocked_open) {
1324 if (state->close_delay)
1325 msleep_interruptible(state->close_delay);
1326 } else if (!uart_console(port)) {
1327 uart_change_pm(state, 3);
1328 }
1329
1330 /*
1331 * Wake up anyone trying to open this port.
1332 */
1333 state->info->flags &= ~UIF_NORMAL_ACTIVE;
1334 wake_up_interruptible(&state->info->open_wait);
1335
1336 done:
Ingo Molnare2862f62006-01-13 21:37:07 +00001337 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338}
1339
1340static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
1341{
1342 struct uart_state *state = tty->driver_data;
1343 struct uart_port *port = state->port;
1344 unsigned long char_time, expire;
1345
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 if (port->type == PORT_UNKNOWN || port->fifosize == 0)
1347 return;
1348
Alan Coxf34d7a52008-04-30 00:54:13 -07001349 lock_kernel();
1350
Linus Torvalds1da177e2005-04-16 15:20:36 -07001351 /*
1352 * Set the check interval to be 1/5 of the estimated time to
1353 * send a single character, and make it at least 1. The check
1354 * interval should also be less than the timeout.
1355 *
1356 * Note: we have to use pretty tight timings here to satisfy
1357 * the NIST-PCTS.
1358 */
1359 char_time = (port->timeout - HZ/50) / port->fifosize;
1360 char_time = char_time / 5;
1361 if (char_time == 0)
1362 char_time = 1;
1363 if (timeout && timeout < char_time)
1364 char_time = timeout;
1365
1366 /*
1367 * If the transmitter hasn't cleared in twice the approximate
1368 * amount of time to send the entire FIFO, it probably won't
1369 * ever clear. This assumes the UART isn't doing flow
1370 * control, which is currently the case. Hence, if it ever
1371 * takes longer than port->timeout, this is probably due to a
1372 * UART bug of some kind. So, we clamp the timeout parameter at
1373 * 2*port->timeout.
1374 */
1375 if (timeout == 0 || timeout > 2 * port->timeout)
1376 timeout = 2 * port->timeout;
1377
1378 expire = jiffies + timeout;
1379
Jiri Slabyeb3a1e12007-05-06 14:48:52 -07001380 pr_debug("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n",
Alan Coxa46c9992008-02-08 04:18:53 -08001381 port->line, jiffies, expire);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001382
1383 /*
1384 * Check whether the transmitter is empty every 'char_time'.
1385 * 'timeout' / 'expire' give us the maximum amount of time
1386 * we wait.
1387 */
1388 while (!port->ops->tx_empty(port)) {
1389 msleep_interruptible(jiffies_to_msecs(char_time));
1390 if (signal_pending(current))
1391 break;
1392 if (time_after(jiffies, expire))
1393 break;
1394 }
1395 set_current_state(TASK_RUNNING); /* might not be needed */
Alan Coxf34d7a52008-04-30 00:54:13 -07001396 unlock_kernel();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397}
1398
1399/*
1400 * This is called with the BKL held in
1401 * linux/drivers/char/tty_io.c:do_tty_hangup()
1402 * We're called from the eventd thread, so we can sleep for
1403 * a _short_ time only.
1404 */
1405static void uart_hangup(struct tty_struct *tty)
1406{
1407 struct uart_state *state = tty->driver_data;
1408
1409 BUG_ON(!kernel_locked());
Jiri Slabyeb3a1e12007-05-06 14:48:52 -07001410 pr_debug("uart_hangup(%d)\n", state->port->line);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411
Ingo Molnare2862f62006-01-13 21:37:07 +00001412 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 if (state->info && state->info->flags & UIF_NORMAL_ACTIVE) {
1414 uart_flush_buffer(tty);
1415 uart_shutdown(state);
1416 state->count = 0;
1417 state->info->flags &= ~UIF_NORMAL_ACTIVE;
1418 state->info->tty = NULL;
1419 wake_up_interruptible(&state->info->open_wait);
1420 wake_up_interruptible(&state->info->delta_msr_wait);
1421 }
Ingo Molnare2862f62006-01-13 21:37:07 +00001422 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001423}
1424
1425/*
1426 * Copy across the serial console cflag setting into the termios settings
1427 * for the initial open of the port. This allows continuity between the
1428 * kernel settings, and the settings init adopts when it opens the port
1429 * for the first time.
1430 */
1431static void uart_update_termios(struct uart_state *state)
1432{
1433 struct tty_struct *tty = state->info->tty;
1434 struct uart_port *port = state->port;
1435
1436 if (uart_console(port) && port->cons->cflag) {
1437 tty->termios->c_cflag = port->cons->cflag;
1438 port->cons->cflag = 0;
1439 }
1440
1441 /*
1442 * If the device failed to grab its irq resources,
1443 * or some other error occurred, don't try to talk
1444 * to the port hardware.
1445 */
1446 if (!(tty->flags & (1 << TTY_IO_ERROR))) {
1447 /*
1448 * Make termios settings take effect.
1449 */
1450 uart_change_speed(state, NULL);
1451
1452 /*
1453 * And finally enable the RTS and DTR signals.
1454 */
1455 if (tty->termios->c_cflag & CBAUD)
1456 uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1457 }
1458}
1459
1460/*
1461 * Block the open until the port is ready. We must be called with
1462 * the per-port semaphore held.
1463 */
1464static int
1465uart_block_til_ready(struct file *filp, struct uart_state *state)
1466{
1467 DECLARE_WAITQUEUE(wait, current);
1468 struct uart_info *info = state->info;
1469 struct uart_port *port = state->port;
Russell Kingc5f46442005-06-29 09:42:38 +01001470 unsigned int mctrl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001471
1472 info->blocked_open++;
1473 state->count--;
1474
1475 add_wait_queue(&info->open_wait, &wait);
1476 while (1) {
1477 set_current_state(TASK_INTERRUPTIBLE);
1478
1479 /*
1480 * If we have been hung up, tell userspace/restart open.
1481 */
1482 if (tty_hung_up_p(filp) || info->tty == NULL)
1483 break;
1484
1485 /*
1486 * If the port has been closed, tell userspace/restart open.
1487 */
1488 if (!(info->flags & UIF_INITIALIZED))
1489 break;
1490
1491 /*
1492 * If non-blocking mode is set, or CLOCAL mode is set,
1493 * we don't want to wait for the modem status lines to
1494 * indicate that the port is ready.
1495 *
1496 * Also, if the port is not enabled/configured, we want
1497 * to allow the open to succeed here. Note that we will
1498 * have set TTY_IO_ERROR for a non-existant port.
1499 */
1500 if ((filp->f_flags & O_NONBLOCK) ||
Alan Coxa46c9992008-02-08 04:18:53 -08001501 (info->tty->termios->c_cflag & CLOCAL) ||
1502 (info->tty->flags & (1 << TTY_IO_ERROR)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001503 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504
1505 /*
1506 * Set DTR to allow modem to know we're waiting. Do
1507 * not set RTS here - we want to make sure we catch
1508 * the data from the modem.
1509 */
1510 if (info->tty->termios->c_cflag & CBAUD)
1511 uart_set_mctrl(port, TIOCM_DTR);
1512
1513 /*
1514 * and wait for the carrier to indicate that the
1515 * modem is ready for us.
1516 */
Russell Kingc5f46442005-06-29 09:42:38 +01001517 spin_lock_irq(&port->lock);
Russell Kingf61051c2006-01-07 23:11:23 +00001518 port->ops->enable_ms(port);
Russell Kingc5f46442005-06-29 09:42:38 +01001519 mctrl = port->ops->get_mctrl(port);
1520 spin_unlock_irq(&port->lock);
1521 if (mctrl & TIOCM_CAR)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001522 break;
1523
Ingo Molnare2862f62006-01-13 21:37:07 +00001524 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001525 schedule();
Ingo Molnare2862f62006-01-13 21:37:07 +00001526 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527
1528 if (signal_pending(current))
1529 break;
1530 }
1531 set_current_state(TASK_RUNNING);
1532 remove_wait_queue(&info->open_wait, &wait);
1533
1534 state->count++;
1535 info->blocked_open--;
1536
1537 if (signal_pending(current))
1538 return -ERESTARTSYS;
1539
1540 if (!info->tty || tty_hung_up_p(filp))
1541 return -EAGAIN;
1542
1543 return 0;
1544}
1545
1546static struct uart_state *uart_get(struct uart_driver *drv, int line)
1547{
1548 struct uart_state *state;
Russell King68ac64c2006-04-30 11:13:50 +01001549 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001550
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551 state = drv->state + line;
Ingo Molnare2862f62006-01-13 21:37:07 +00001552 if (mutex_lock_interruptible(&state->mutex)) {
Russell King68ac64c2006-04-30 11:13:50 +01001553 ret = -ERESTARTSYS;
1554 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 }
1556
1557 state->count++;
Russell King68ac64c2006-04-30 11:13:50 +01001558 if (!state->port || state->port->flags & UPF_DEAD) {
1559 ret = -ENXIO;
1560 goto err_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561 }
1562
1563 if (!state->info) {
Burman Yan8f31bb32007-02-14 00:33:07 -08001564 state->info = kzalloc(sizeof(struct uart_info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001565 if (state->info) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566 init_waitqueue_head(&state->info->open_wait);
1567 init_waitqueue_head(&state->info->delta_msr_wait);
1568
1569 /*
1570 * Link the info into the other structures.
1571 */
1572 state->port->info = state->info;
1573
1574 tasklet_init(&state->info->tlet, uart_tasklet_action,
1575 (unsigned long)state);
1576 } else {
Russell King68ac64c2006-04-30 11:13:50 +01001577 ret = -ENOMEM;
1578 goto err_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001579 }
1580 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001581 return state;
Russell King68ac64c2006-04-30 11:13:50 +01001582
1583 err_unlock:
1584 state->count--;
1585 mutex_unlock(&state->mutex);
1586 err:
1587 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588}
1589
1590/*
Denis Cheng922f9cf2008-02-08 04:22:00 -08001591 * calls to uart_open are serialised by the BKL in
1592 * fs/char_dev.c:chrdev_open()
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 * Note that if this fails, then uart_close() _will_ be called.
1594 *
1595 * In time, we want to scrap the "opening nonpresent ports"
1596 * behaviour and implement an alternative way for setserial
1597 * to set base addresses/ports/types. This will allow us to
1598 * get rid of a certain amount of extra tests.
1599 */
1600static int uart_open(struct tty_struct *tty, struct file *filp)
1601{
1602 struct uart_driver *drv = (struct uart_driver *)tty->driver->driver_state;
1603 struct uart_state *state;
1604 int retval, line = tty->index;
1605
1606 BUG_ON(!kernel_locked());
Jiri Slabyeb3a1e12007-05-06 14:48:52 -07001607 pr_debug("uart_open(%d) called\n", line);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608
1609 /*
1610 * tty->driver->num won't change, so we won't fail here with
1611 * tty->driver_data set to something non-NULL (and therefore
1612 * we won't get caught by uart_close()).
1613 */
1614 retval = -ENODEV;
1615 if (line >= tty->driver->num)
1616 goto fail;
1617
1618 /*
1619 * We take the semaphore inside uart_get to guarantee that we won't
1620 * be re-entered while allocating the info structure, or while we
1621 * request any IRQs that the driver may need. This also has the nice
1622 * side-effect that it delays the action of uart_hangup, so we can
1623 * guarantee that info->tty will always contain something reasonable.
1624 */
1625 state = uart_get(drv, line);
1626 if (IS_ERR(state)) {
1627 retval = PTR_ERR(state);
1628 goto fail;
1629 }
1630
1631 /*
1632 * Once we set tty->driver_data here, we are guaranteed that
1633 * uart_close() will decrement the driver module use count.
1634 * Any failures from here onwards should not touch the count.
1635 */
1636 tty->driver_data = state;
1637 tty->low_latency = (state->port->flags & UPF_LOW_LATENCY) ? 1 : 0;
1638 tty->alt_speed = 0;
1639 state->info->tty = tty;
1640
1641 /*
1642 * If the port is in the middle of closing, bail out now.
1643 */
1644 if (tty_hung_up_p(filp)) {
1645 retval = -EAGAIN;
1646 state->count--;
Ingo Molnare2862f62006-01-13 21:37:07 +00001647 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001648 goto fail;
1649 }
1650
1651 /*
1652 * Make sure the device is in D0 state.
1653 */
1654 if (state->count == 1)
1655 uart_change_pm(state, 0);
1656
1657 /*
1658 * Start up the serial port.
1659 */
1660 retval = uart_startup(state, 0);
1661
1662 /*
1663 * If we succeeded, wait until the port is ready.
1664 */
1665 if (retval == 0)
1666 retval = uart_block_til_ready(filp, state);
Ingo Molnare2862f62006-01-13 21:37:07 +00001667 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001668
1669 /*
1670 * If this is the first open to succeed, adjust things to suit.
1671 */
1672 if (retval == 0 && !(state->info->flags & UIF_NORMAL_ACTIVE)) {
1673 state->info->flags |= UIF_NORMAL_ACTIVE;
1674
1675 uart_update_termios(state);
1676 }
1677
1678 fail:
1679 return retval;
1680}
1681
1682static const char *uart_type(struct uart_port *port)
1683{
1684 const char *str = NULL;
1685
1686 if (port->ops->type)
1687 str = port->ops->type(port);
1688
1689 if (!str)
1690 str = "unknown";
1691
1692 return str;
1693}
1694
1695#ifdef CONFIG_PROC_FS
1696
1697static int uart_line_info(char *buf, struct uart_driver *drv, int i)
1698{
1699 struct uart_state *state = drv->state + i;
George G. Davis3689a0e2007-02-14 00:33:06 -08001700 int pm_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001701 struct uart_port *port = state->port;
1702 char stat_buf[32];
1703 unsigned int status;
Sergei Shtylyov6c6a2332006-09-04 00:04:20 +04001704 int mmio, ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001705
1706 if (!port)
1707 return 0;
1708
Sergei Shtylyov6c6a2332006-09-04 00:04:20 +04001709 mmio = port->iotype >= UPIO_MEM;
Josh Boyer4f640ef2007-07-23 18:43:44 -07001710 ret = sprintf(buf, "%d: uart:%s %s%08llX irq:%d",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001711 port->line, uart_type(port),
Sergei Shtylyov6c6a2332006-09-04 00:04:20 +04001712 mmio ? "mmio:0x" : "port:",
Josh Boyer4f640ef2007-07-23 18:43:44 -07001713 mmio ? (unsigned long long)port->mapbase
Alan Coxa46c9992008-02-08 04:18:53 -08001714 : (unsigned long long) port->iobase,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001715 port->irq);
1716
1717 if (port->type == PORT_UNKNOWN) {
1718 strcat(buf, "\n");
1719 return ret + 1;
1720 }
1721
Alan Coxa46c9992008-02-08 04:18:53 -08001722 if (capable(CAP_SYS_ADMIN)) {
George G. Davis3689a0e2007-02-14 00:33:06 -08001723 mutex_lock(&state->mutex);
1724 pm_state = state->pm_state;
1725 if (pm_state)
1726 uart_change_pm(state, 0);
Russell Kingc5f46442005-06-29 09:42:38 +01001727 spin_lock_irq(&port->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001728 status = port->ops->get_mctrl(port);
Russell Kingc5f46442005-06-29 09:42:38 +01001729 spin_unlock_irq(&port->lock);
George G. Davis3689a0e2007-02-14 00:33:06 -08001730 if (pm_state)
1731 uart_change_pm(state, pm_state);
1732 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001733
1734 ret += sprintf(buf + ret, " tx:%d rx:%d",
1735 port->icount.tx, port->icount.rx);
1736 if (port->icount.frame)
1737 ret += sprintf(buf + ret, " fe:%d",
1738 port->icount.frame);
1739 if (port->icount.parity)
1740 ret += sprintf(buf + ret, " pe:%d",
1741 port->icount.parity);
1742 if (port->icount.brk)
1743 ret += sprintf(buf + ret, " brk:%d",
1744 port->icount.brk);
1745 if (port->icount.overrun)
1746 ret += sprintf(buf + ret, " oe:%d",
1747 port->icount.overrun);
Alan Coxa46c9992008-02-08 04:18:53 -08001748
1749#define INFOBIT(bit, str) \
Linus Torvalds1da177e2005-04-16 15:20:36 -07001750 if (port->mctrl & (bit)) \
1751 strncat(stat_buf, (str), sizeof(stat_buf) - \
1752 strlen(stat_buf) - 2)
Alan Coxa46c9992008-02-08 04:18:53 -08001753#define STATBIT(bit, str) \
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 if (status & (bit)) \
1755 strncat(stat_buf, (str), sizeof(stat_buf) - \
1756 strlen(stat_buf) - 2)
1757
1758 stat_buf[0] = '\0';
1759 stat_buf[1] = '\0';
1760 INFOBIT(TIOCM_RTS, "|RTS");
1761 STATBIT(TIOCM_CTS, "|CTS");
1762 INFOBIT(TIOCM_DTR, "|DTR");
1763 STATBIT(TIOCM_DSR, "|DSR");
1764 STATBIT(TIOCM_CAR, "|CD");
1765 STATBIT(TIOCM_RNG, "|RI");
1766 if (stat_buf[0])
1767 stat_buf[0] = ' ';
1768 strcat(stat_buf, "\n");
Alan Coxa46c9992008-02-08 04:18:53 -08001769
Linus Torvalds1da177e2005-04-16 15:20:36 -07001770 ret += sprintf(buf + ret, stat_buf);
1771 } else {
1772 strcat(buf, "\n");
1773 ret++;
1774 }
1775#undef STATBIT
1776#undef INFOBIT
1777 return ret;
1778}
1779
1780static int uart_read_proc(char *page, char **start, off_t off,
1781 int count, int *eof, void *data)
1782{
1783 struct tty_driver *ttydrv = data;
1784 struct uart_driver *drv = ttydrv->driver_state;
1785 int i, len = 0, l;
1786 off_t begin = 0;
1787
1788 len += sprintf(page, "serinfo:1.0 driver%s%s revision:%s\n",
1789 "", "", "");
1790 for (i = 0; i < drv->nr && len < PAGE_SIZE - 96; i++) {
1791 l = uart_line_info(page + len, drv, i);
1792 len += l;
1793 if (len + begin > off + count)
1794 goto done;
1795 if (len + begin < off) {
1796 begin += len;
1797 len = 0;
1798 }
1799 }
1800 *eof = 1;
1801 done:
1802 if (off >= len + begin)
1803 return 0;
1804 *start = page + (off - begin);
1805 return (count < begin + len - off) ? count : (begin + len - off);
1806}
1807#endif
1808
Andrew Morton4a1b5502008-03-07 15:51:16 -08001809#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001810/*
Russell Kingd3587882006-03-20 20:00:09 +00001811 * uart_console_write - write a console message to a serial port
1812 * @port: the port to write the message
1813 * @s: array of characters
1814 * @count: number of characters in string to write
1815 * @write: function to write character to port
1816 */
1817void uart_console_write(struct uart_port *port, const char *s,
1818 unsigned int count,
1819 void (*putchar)(struct uart_port *, int))
1820{
1821 unsigned int i;
1822
1823 for (i = 0; i < count; i++, s++) {
1824 if (*s == '\n')
1825 putchar(port, '\r');
1826 putchar(port, *s);
1827 }
1828}
1829EXPORT_SYMBOL_GPL(uart_console_write);
1830
1831/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001832 * Check whether an invalid uart number has been specified, and
1833 * if so, search for the first available port that does have
1834 * console support.
1835 */
1836struct uart_port * __init
1837uart_get_console(struct uart_port *ports, int nr, struct console *co)
1838{
1839 int idx = co->index;
1840
1841 if (idx < 0 || idx >= nr || (ports[idx].iobase == 0 &&
1842 ports[idx].membase == NULL))
1843 for (idx = 0; idx < nr; idx++)
1844 if (ports[idx].iobase != 0 ||
1845 ports[idx].membase != NULL)
1846 break;
1847
1848 co->index = idx;
1849
1850 return ports + idx;
1851}
1852
1853/**
1854 * uart_parse_options - Parse serial port baud/parity/bits/flow contro.
1855 * @options: pointer to option string
1856 * @baud: pointer to an 'int' variable for the baud rate.
1857 * @parity: pointer to an 'int' variable for the parity.
1858 * @bits: pointer to an 'int' variable for the number of data bits.
1859 * @flow: pointer to an 'int' variable for the flow control character.
1860 *
1861 * uart_parse_options decodes a string containing the serial console
1862 * options. The format of the string is <baud><parity><bits><flow>,
1863 * eg: 115200n8r
1864 */
Jason Wesself2d937f2008-04-17 20:05:37 +02001865void
Linus Torvalds1da177e2005-04-16 15:20:36 -07001866uart_parse_options(char *options, int *baud, int *parity, int *bits, int *flow)
1867{
1868 char *s = options;
1869
1870 *baud = simple_strtoul(s, NULL, 10);
1871 while (*s >= '0' && *s <= '9')
1872 s++;
1873 if (*s)
1874 *parity = *s++;
1875 if (*s)
1876 *bits = *s++ - '0';
1877 if (*s)
1878 *flow = *s;
1879}
Jason Wesself2d937f2008-04-17 20:05:37 +02001880EXPORT_SYMBOL_GPL(uart_parse_options);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001881
1882struct baud_rates {
1883 unsigned int rate;
1884 unsigned int cflag;
1885};
1886
Arjan van de Vencb3592b2005-11-28 21:04:11 +00001887static const struct baud_rates baud_rates[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001888 { 921600, B921600 },
1889 { 460800, B460800 },
1890 { 230400, B230400 },
1891 { 115200, B115200 },
1892 { 57600, B57600 },
1893 { 38400, B38400 },
1894 { 19200, B19200 },
1895 { 9600, B9600 },
1896 { 4800, B4800 },
1897 { 2400, B2400 },
1898 { 1200, B1200 },
1899 { 0, B38400 }
1900};
1901
1902/**
1903 * uart_set_options - setup the serial console parameters
1904 * @port: pointer to the serial ports uart_port structure
1905 * @co: console pointer
1906 * @baud: baud rate
1907 * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
1908 * @bits: number of data bits
1909 * @flow: flow control character - 'r' (rts)
1910 */
Jason Wesself2d937f2008-04-17 20:05:37 +02001911int
Linus Torvalds1da177e2005-04-16 15:20:36 -07001912uart_set_options(struct uart_port *port, struct console *co,
1913 int baud, int parity, int bits, int flow)
1914{
Alan Cox606d0992006-12-08 02:38:45 -08001915 struct ktermios termios;
Alan Cox149b36e2007-10-18 01:24:16 -07001916 static struct ktermios dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917 int i;
1918
Russell King976ecd12005-07-03 21:05:45 +01001919 /*
1920 * Ensure that the serial console lock is initialised
1921 * early.
1922 */
1923 spin_lock_init(&port->lock);
Ingo Molnar13e83592006-07-03 00:25:03 -07001924 lockdep_set_class(&port->lock, &port_lock_key);
Russell King976ecd12005-07-03 21:05:45 +01001925
Alan Cox606d0992006-12-08 02:38:45 -08001926 memset(&termios, 0, sizeof(struct ktermios));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001927
1928 termios.c_cflag = CREAD | HUPCL | CLOCAL;
1929
1930 /*
1931 * Construct a cflag setting.
1932 */
1933 for (i = 0; baud_rates[i].rate; i++)
1934 if (baud_rates[i].rate <= baud)
1935 break;
1936
1937 termios.c_cflag |= baud_rates[i].cflag;
1938
1939 if (bits == 7)
1940 termios.c_cflag |= CS7;
1941 else
1942 termios.c_cflag |= CS8;
1943
1944 switch (parity) {
1945 case 'o': case 'O':
1946 termios.c_cflag |= PARODD;
1947 /*fall through*/
1948 case 'e': case 'E':
1949 termios.c_cflag |= PARENB;
1950 break;
1951 }
1952
1953 if (flow == 'r')
1954 termios.c_cflag |= CRTSCTS;
1955
Yinghai Lu79492682007-07-15 23:37:25 -07001956 /*
1957 * some uarts on other side don't support no flow control.
1958 * So we set * DTR in host uart to make them happy
1959 */
1960 port->mctrl |= TIOCM_DTR;
1961
Alan Cox149b36e2007-10-18 01:24:16 -07001962 port->ops->set_termios(port, &termios, &dummy);
Jason Wesself2d937f2008-04-17 20:05:37 +02001963 /*
1964 * Allow the setting of the UART parameters with a NULL console
1965 * too:
1966 */
1967 if (co)
1968 co->cflag = termios.c_cflag;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969
1970 return 0;
1971}
Jason Wesself2d937f2008-04-17 20:05:37 +02001972EXPORT_SYMBOL_GPL(uart_set_options);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001973#endif /* CONFIG_SERIAL_CORE_CONSOLE */
1974
1975static void uart_change_pm(struct uart_state *state, int pm_state)
1976{
1977 struct uart_port *port = state->port;
Andrew Victor1281e362006-05-16 11:28:49 +01001978
1979 if (state->pm_state != pm_state) {
1980 if (port->ops->pm)
1981 port->ops->pm(port, pm_state, state->pm_state);
1982 state->pm_state = pm_state;
1983 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001984}
1985
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07001986struct uart_match {
1987 struct uart_port *port;
1988 struct uart_driver *driver;
1989};
1990
1991static int serial_match_port(struct device *dev, void *data)
1992{
1993 struct uart_match *match = data;
1994 dev_t devt = MKDEV(match->driver->major, match->driver->minor) + match->port->line;
1995
1996 return dev->devt == devt; /* Actually, only one tty per port */
1997}
1998
Linus Torvalds1da177e2005-04-16 15:20:36 -07001999int uart_suspend_port(struct uart_driver *drv, struct uart_port *port)
2000{
2001 struct uart_state *state = drv->state + port->line;
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07002002 struct device *tty_dev;
2003 struct uart_match match = {port, drv};
Linus Torvalds1da177e2005-04-16 15:20:36 -07002004
Ingo Molnare2862f62006-01-13 21:37:07 +00002005 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002006
Andres Salomon8f4ce8c2007-10-18 03:04:50 -07002007 if (!console_suspend_enabled && uart_console(port)) {
2008 /* we're going to avoid suspending serial console */
Rafael J. Wysockie1da95a2006-09-25 23:32:57 -07002009 mutex_unlock(&state->mutex);
2010 return 0;
2011 }
Rafael J. Wysockie1da95a2006-09-25 23:32:57 -07002012
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07002013 tty_dev = device_find_child(port->dev, &match, serial_match_port);
2014 if (device_may_wakeup(tty_dev)) {
2015 enable_irq_wake(port->irq);
2016 put_device(tty_dev);
2017 mutex_unlock(&state->mutex);
2018 return 0;
2019 }
2020 port->suspended = 1;
2021
Linus Torvalds1da177e2005-04-16 15:20:36 -07002022 if (state->info && state->info->flags & UIF_INITIALIZED) {
Russell Kingba899db2006-01-21 22:45:50 +00002023 const struct uart_ops *ops = port->ops;
Russell Kingc8c6bfa2008-02-04 22:27:52 -08002024 int tries;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002025
Russell Kinga6b93a92006-10-01 17:17:40 +01002026 state->info->flags = (state->info->flags & ~UIF_INITIALIZED)
2027 | UIF_SUSPENDED;
2028
Linus Torvalds1da177e2005-04-16 15:20:36 -07002029 spin_lock_irq(&port->lock);
Russell Kingb129a8c2005-08-31 10:12:14 +01002030 ops->stop_tx(port);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002031 ops->set_mctrl(port, 0);
2032 ops->stop_rx(port);
2033 spin_unlock_irq(&port->lock);
2034
2035 /*
2036 * Wait for the transmitter to empty.
2037 */
Alan Coxa46c9992008-02-08 04:18:53 -08002038 for (tries = 3; !ops->tx_empty(port) && tries; tries--)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002039 msleep(10);
Russell Kingc8c6bfa2008-02-04 22:27:52 -08002040 if (!tries)
Alan Coxa46c9992008-02-08 04:18:53 -08002041 printk(KERN_ERR "%s%s%s%d: Unable to drain "
2042 "transmitter\n",
Russell Kingc8c6bfa2008-02-04 22:27:52 -08002043 port->dev ? port->dev->bus_id : "",
2044 port->dev ? ": " : "",
2045 drv->dev_name, port->line);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002046
2047 ops->shutdown(port);
2048 }
2049
2050 /*
2051 * Disable the console device before suspending.
2052 */
2053 if (uart_console(port))
2054 console_stop(port->cons);
2055
2056 uart_change_pm(state, 3);
2057
Ingo Molnare2862f62006-01-13 21:37:07 +00002058 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002059
2060 return 0;
2061}
2062
2063int uart_resume_port(struct uart_driver *drv, struct uart_port *port)
2064{
2065 struct uart_state *state = drv->state + port->line;
Arjan van de Ven03a74dc2008-05-23 13:04:49 -07002066 struct device *tty_dev;
2067 struct uart_match match = {port, drv};
Linus Torvalds1da177e2005-04-16 15:20:36 -07002068
Ingo Molnare2862f62006-01-13 21:37:07 +00002069 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002070
Andres Salomon8f4ce8c2007-10-18 03:04:50 -07002071 if (!console_suspend_enabled && uart_console(port)) {
2072 /* no need to resume serial console, it wasn't suspended */
Rafael J. Wysockie1da95a2006-09-25 23:32:57 -07002073 mutex_unlock(&state->mutex);
2074 return 0;
2075 }
Rafael J. Wysockie1da95a2006-09-25 23:32:57 -07002076
Arjan van de Ven03a74dc2008-05-23 13:04:49 -07002077 tty_dev = device_find_child(port->dev, &match, serial_match_port);
2078 if (!port->suspended && device_may_wakeup(tty_dev)) {
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07002079 disable_irq_wake(port->irq);
2080 mutex_unlock(&state->mutex);
2081 return 0;
2082 }
2083 port->suspended = 0;
2084
Linus Torvalds1da177e2005-04-16 15:20:36 -07002085 /*
2086 * Re-enable the console device after suspending.
2087 */
2088 if (uart_console(port)) {
Alan Cox606d0992006-12-08 02:38:45 -08002089 struct ktermios termios;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002090
2091 /*
2092 * First try to use the console cflag setting.
2093 */
Alan Cox606d0992006-12-08 02:38:45 -08002094 memset(&termios, 0, sizeof(struct ktermios));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002095 termios.c_cflag = port->cons->cflag;
2096
2097 /*
2098 * If that's unset, use the tty termios setting.
2099 */
2100 if (state->info && state->info->tty && termios.c_cflag == 0)
2101 termios = *state->info->tty->termios;
2102
Russell King9d778a62008-02-04 22:27:51 -08002103 uart_change_pm(state, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002104 port->ops->set_termios(port, &termios, NULL);
2105 console_start(port->cons);
2106 }
2107
Russell Kinga6b93a92006-10-01 17:17:40 +01002108 if (state->info && state->info->flags & UIF_SUSPENDED) {
Russell Kingba899db2006-01-21 22:45:50 +00002109 const struct uart_ops *ops = port->ops;
Russell Kingee31b332005-11-13 15:28:51 +00002110 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002111
Russell King9d778a62008-02-04 22:27:51 -08002112 uart_change_pm(state, 0);
Alan Coxf34d7a52008-04-30 00:54:13 -07002113 spin_lock_irq(&port->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002114 ops->set_mctrl(port, 0);
Alan Coxf34d7a52008-04-30 00:54:13 -07002115 spin_unlock_irq(&port->lock);
Russell Kingee31b332005-11-13 15:28:51 +00002116 ret = ops->startup(port);
2117 if (ret == 0) {
2118 uart_change_speed(state, NULL);
2119 spin_lock_irq(&port->lock);
2120 ops->set_mctrl(port, port->mctrl);
2121 ops->start_tx(port);
2122 spin_unlock_irq(&port->lock);
Russell Kinga6b93a92006-10-01 17:17:40 +01002123 state->info->flags |= UIF_INITIALIZED;
Russell Kingee31b332005-11-13 15:28:51 +00002124 } else {
2125 /*
2126 * Failed to resume - maybe hardware went away?
2127 * Clear the "initialized" flag so we won't try
2128 * to call the low level drivers shutdown method.
2129 */
Russell Kingee31b332005-11-13 15:28:51 +00002130 uart_shutdown(state);
2131 }
Russell Kinga6b93a92006-10-01 17:17:40 +01002132
2133 state->info->flags &= ~UIF_SUSPENDED;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002134 }
2135
Ingo Molnare2862f62006-01-13 21:37:07 +00002136 mutex_unlock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002137
2138 return 0;
2139}
2140
2141static inline void
2142uart_report_port(struct uart_driver *drv, struct uart_port *port)
2143{
Russell King30b7a3b2005-09-03 15:30:21 +01002144 char address[64];
2145
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146 switch (port->iotype) {
2147 case UPIO_PORT:
Russell King30b7a3b2005-09-03 15:30:21 +01002148 snprintf(address, sizeof(address),
2149 "I/O 0x%x", port->iobase);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002150 break;
2151 case UPIO_HUB6:
Russell King30b7a3b2005-09-03 15:30:21 +01002152 snprintf(address, sizeof(address),
2153 "I/O 0x%x offset 0x%x", port->iobase, port->hub6);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002154 break;
2155 case UPIO_MEM:
2156 case UPIO_MEM32:
Pantelis Antoniou21c614a2005-11-06 09:07:03 +00002157 case UPIO_AU:
Zang Roy-r619113be91ec2006-06-30 02:29:58 -07002158 case UPIO_TSI:
Marc St-Jeanbeab6972007-05-06 14:48:45 -07002159 case UPIO_DWAPB:
Russell King30b7a3b2005-09-03 15:30:21 +01002160 snprintf(address, sizeof(address),
Josh Boyer4f640ef2007-07-23 18:43:44 -07002161 "MMIO 0x%llx", (unsigned long long)port->mapbase);
Russell King30b7a3b2005-09-03 15:30:21 +01002162 break;
2163 default:
2164 strlcpy(address, "*unknown*", sizeof(address));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002165 break;
2166 }
Russell King30b7a3b2005-09-03 15:30:21 +01002167
Russell King0cf669d2005-10-31 11:42:22 +00002168 printk(KERN_INFO "%s%s%s%d at %s (irq = %d) is a %s\n",
2169 port->dev ? port->dev->bus_id : "",
2170 port->dev ? ": " : "",
Russell King30b7a3b2005-09-03 15:30:21 +01002171 drv->dev_name, port->line, address, port->irq, uart_type(port));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002172}
2173
2174static void
2175uart_configure_port(struct uart_driver *drv, struct uart_state *state,
2176 struct uart_port *port)
2177{
2178 unsigned int flags;
2179
2180 /*
2181 * If there isn't a port here, don't do anything further.
2182 */
2183 if (!port->iobase && !port->mapbase && !port->membase)
2184 return;
2185
2186 /*
2187 * Now do the auto configuration stuff. Note that config_port
2188 * is expected to claim the resources and map the port for us.
2189 */
2190 flags = UART_CONFIG_TYPE;
2191 if (port->flags & UPF_AUTO_IRQ)
2192 flags |= UART_CONFIG_IRQ;
2193 if (port->flags & UPF_BOOT_AUTOCONF) {
2194 port->type = PORT_UNKNOWN;
2195 port->ops->config_port(port, flags);
2196 }
2197
2198 if (port->type != PORT_UNKNOWN) {
2199 unsigned long flags;
2200
2201 uart_report_port(drv, port);
2202
George G. Davis3689a0e2007-02-14 00:33:06 -08002203 /* Power up port for set_mctrl() */
2204 uart_change_pm(state, 0);
2205
Linus Torvalds1da177e2005-04-16 15:20:36 -07002206 /*
2207 * Ensure that the modem control lines are de-activated.
Yinghai Luc3e46422008-02-04 22:27:46 -08002208 * keep the DTR setting that is set in uart_set_options()
Linus Torvalds1da177e2005-04-16 15:20:36 -07002209 * We probably don't need a spinlock around this, but
2210 */
2211 spin_lock_irqsave(&port->lock, flags);
Yinghai Luc3e46422008-02-04 22:27:46 -08002212 port->ops->set_mctrl(port, port->mctrl & TIOCM_DTR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002213 spin_unlock_irqrestore(&port->lock, flags);
2214
2215 /*
Russell King97d97222007-09-01 21:25:09 +01002216 * If this driver supports console, and it hasn't been
2217 * successfully registered yet, try to re-register it.
2218 * It may be that the port was not available.
2219 */
2220 if (port->cons && !(port->cons->flags & CON_ENABLED))
2221 register_console(port->cons);
2222
2223 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002224 * Power down all ports by default, except the
2225 * console if we have one.
2226 */
2227 if (!uart_console(port))
2228 uart_change_pm(state, 3);
2229 }
2230}
2231
Jason Wesself2d937f2008-04-17 20:05:37 +02002232#ifdef CONFIG_CONSOLE_POLL
2233
2234static int uart_poll_init(struct tty_driver *driver, int line, char *options)
2235{
2236 struct uart_driver *drv = driver->driver_state;
2237 struct uart_state *state = drv->state + line;
2238 struct uart_port *port;
2239 int baud = 9600;
2240 int bits = 8;
2241 int parity = 'n';
2242 int flow = 'n';
2243
2244 if (!state || !state->port)
2245 return -1;
2246
2247 port = state->port;
2248 if (!(port->ops->poll_get_char && port->ops->poll_put_char))
2249 return -1;
2250
2251 if (options) {
2252 uart_parse_options(options, &baud, &parity, &bits, &flow);
2253 return uart_set_options(port, NULL, baud, parity, bits, flow);
2254 }
2255
2256 return 0;
2257}
2258
2259static int uart_poll_get_char(struct tty_driver *driver, int line)
2260{
2261 struct uart_driver *drv = driver->driver_state;
2262 struct uart_state *state = drv->state + line;
2263 struct uart_port *port;
2264
2265 if (!state || !state->port)
2266 return -1;
2267
2268 port = state->port;
2269 return port->ops->poll_get_char(port);
2270}
2271
2272static void uart_poll_put_char(struct tty_driver *driver, int line, char ch)
2273{
2274 struct uart_driver *drv = driver->driver_state;
2275 struct uart_state *state = drv->state + line;
2276 struct uart_port *port;
2277
2278 if (!state || !state->port)
2279 return;
2280
2281 port = state->port;
2282 port->ops->poll_put_char(port, ch);
2283}
2284#endif
2285
Jeff Dikeb68e31d2006-10-02 02:17:18 -07002286static const struct tty_operations uart_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002287 .open = uart_open,
2288 .close = uart_close,
2289 .write = uart_write,
2290 .put_char = uart_put_char,
2291 .flush_chars = uart_flush_chars,
2292 .write_room = uart_write_room,
2293 .chars_in_buffer= uart_chars_in_buffer,
2294 .flush_buffer = uart_flush_buffer,
2295 .ioctl = uart_ioctl,
2296 .throttle = uart_throttle,
2297 .unthrottle = uart_unthrottle,
2298 .send_xchar = uart_send_xchar,
2299 .set_termios = uart_set_termios,
Alan Cox64e91592008-06-03 15:18:54 +01002300 .set_ldisc = uart_set_ldisc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002301 .stop = uart_stop,
2302 .start = uart_start,
2303 .hangup = uart_hangup,
2304 .break_ctl = uart_break_ctl,
2305 .wait_until_sent= uart_wait_until_sent,
2306#ifdef CONFIG_PROC_FS
2307 .read_proc = uart_read_proc,
2308#endif
2309 .tiocmget = uart_tiocmget,
2310 .tiocmset = uart_tiocmset,
Jason Wesself2d937f2008-04-17 20:05:37 +02002311#ifdef CONFIG_CONSOLE_POLL
2312 .poll_init = uart_poll_init,
2313 .poll_get_char = uart_poll_get_char,
2314 .poll_put_char = uart_poll_put_char,
2315#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002316};
2317
2318/**
2319 * uart_register_driver - register a driver with the uart core layer
2320 * @drv: low level driver structure
2321 *
2322 * Register a uart driver with the core driver. We in turn register
2323 * with the tty layer, and initialise the core driver per-port state.
2324 *
2325 * We have a proc file in /proc/tty/driver which is named after the
2326 * normal driver.
2327 *
2328 * drv->port should be NULL, and the per-port structures should be
2329 * registered using uart_add_one_port after this call has succeeded.
2330 */
2331int uart_register_driver(struct uart_driver *drv)
2332{
2333 struct tty_driver *normal = NULL;
2334 int i, retval;
2335
2336 BUG_ON(drv->state);
2337
2338 /*
2339 * Maybe we should be using a slab cache for this, especially if
2340 * we have a large number of ports to handle.
2341 */
Burman Yan8f31bb32007-02-14 00:33:07 -08002342 drv->state = kzalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002343 retval = -ENOMEM;
2344 if (!drv->state)
2345 goto out;
2346
Linus Torvalds1da177e2005-04-16 15:20:36 -07002347 normal = alloc_tty_driver(drv->nr);
2348 if (!normal)
2349 goto out;
2350
2351 drv->tty_driver = normal;
2352
2353 normal->owner = drv->owner;
2354 normal->driver_name = drv->driver_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002355 normal->name = drv->dev_name;
2356 normal->major = drv->major;
2357 normal->minor_start = drv->minor;
2358 normal->type = TTY_DRIVER_TYPE_SERIAL;
2359 normal->subtype = SERIAL_TYPE_NORMAL;
2360 normal->init_termios = tty_std_termios;
2361 normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
Alan Cox606d0992006-12-08 02:38:45 -08002362 normal->init_termios.c_ispeed = normal->init_termios.c_ospeed = 9600;
Greg Kroah-Hartman331b8312005-06-20 21:15:16 -07002363 normal->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002364 normal->driver_state = drv;
2365 tty_set_operations(normal, &uart_ops);
2366
2367 /*
2368 * Initialise the UART state(s).
2369 */
2370 for (i = 0; i < drv->nr; i++) {
2371 struct uart_state *state = drv->state + i;
2372
2373 state->close_delay = 500; /* .5 seconds */
2374 state->closing_wait = 30000; /* 30 seconds */
2375
Ingo Molnare2862f62006-01-13 21:37:07 +00002376 mutex_init(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002377 }
2378
2379 retval = tty_register_driver(normal);
2380 out:
2381 if (retval < 0) {
2382 put_tty_driver(normal);
2383 kfree(drv->state);
2384 }
2385 return retval;
2386}
2387
2388/**
2389 * uart_unregister_driver - remove a driver from the uart core layer
2390 * @drv: low level driver structure
2391 *
2392 * Remove all references to a driver from the core driver. The low
2393 * level driver must have removed all its ports via the
2394 * uart_remove_one_port() if it registered them with uart_add_one_port().
2395 * (ie, drv->port == NULL)
2396 */
2397void uart_unregister_driver(struct uart_driver *drv)
2398{
2399 struct tty_driver *p = drv->tty_driver;
2400 tty_unregister_driver(p);
2401 put_tty_driver(p);
2402 kfree(drv->state);
2403 drv->tty_driver = NULL;
2404}
2405
2406struct tty_driver *uart_console_device(struct console *co, int *index)
2407{
2408 struct uart_driver *p = co->data;
2409 *index = co->index;
2410 return p->tty_driver;
2411}
2412
2413/**
2414 * uart_add_one_port - attach a driver-defined port structure
2415 * @drv: pointer to the uart low level driver structure for this port
2416 * @port: uart port structure to use for this port.
2417 *
2418 * This allows the driver to register its own uart_port structure
2419 * with the core driver. The main purpose is to allow the low
2420 * level uart drivers to expand uart_port, rather than having yet
2421 * more levels of structures.
2422 */
2423int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
2424{
2425 struct uart_state *state;
2426 int ret = 0;
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07002427 struct device *tty_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002428
2429 BUG_ON(in_interrupt());
2430
2431 if (port->line >= drv->nr)
2432 return -EINVAL;
2433
2434 state = drv->state + port->line;
2435
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002436 mutex_lock(&port_mutex);
Russell King68ac64c2006-04-30 11:13:50 +01002437 mutex_lock(&state->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002438 if (state->port) {
2439 ret = -EINVAL;
2440 goto out;
2441 }
2442
2443 state->port = port;
Russell King97d97222007-09-01 21:25:09 +01002444 state->pm_state = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002445
Linus Torvalds1da177e2005-04-16 15:20:36 -07002446 port->cons = drv->cons;
2447 port->info = state->info;
2448
Russell King976ecd12005-07-03 21:05:45 +01002449 /*
2450 * If this port is a console, then the spinlock is already
2451 * initialised.
2452 */
Ingo Molnar13e83592006-07-03 00:25:03 -07002453 if (!(uart_console(port) && (port->cons->flags & CON_ENABLED))) {
Russell King976ecd12005-07-03 21:05:45 +01002454 spin_lock_init(&port->lock);
Ingo Molnar13e83592006-07-03 00:25:03 -07002455 lockdep_set_class(&port->lock, &port_lock_key);
2456 }
Russell King976ecd12005-07-03 21:05:45 +01002457
Linus Torvalds1da177e2005-04-16 15:20:36 -07002458 uart_configure_port(drv, state, port);
2459
2460 /*
2461 * Register the port whether it's detected or not. This allows
2462 * setserial to be used to alter this ports parameters.
2463 */
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07002464 tty_dev = tty_register_device(drv->tty_driver, port->line, port->dev);
2465 if (likely(!IS_ERR(tty_dev))) {
Alan Stern74081f82008-03-19 22:35:13 +01002466 device_init_wakeup(tty_dev, 1);
Guennadi Liakhovetskib3b708f2007-10-16 01:24:02 -07002467 device_set_wakeup_enable(tty_dev, 0);
2468 } else
2469 printk(KERN_ERR "Cannot register tty device on line %d\n",
2470 port->line);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002471
2472 /*
Russell King68ac64c2006-04-30 11:13:50 +01002473 * Ensure UPF_DEAD is not set.
2474 */
2475 port->flags &= ~UPF_DEAD;
2476
Linus Torvalds1da177e2005-04-16 15:20:36 -07002477 out:
Russell King68ac64c2006-04-30 11:13:50 +01002478 mutex_unlock(&state->mutex);
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002479 mutex_unlock(&port_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002480
2481 return ret;
2482}
2483
2484/**
2485 * uart_remove_one_port - detach a driver defined port structure
2486 * @drv: pointer to the uart low level driver structure for this port
2487 * @port: uart port structure for this port
2488 *
2489 * This unhooks (and hangs up) the specified port structure from the
2490 * core driver. No further calls will be made to the low-level code
2491 * for this port.
2492 */
2493int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
2494{
2495 struct uart_state *state = drv->state + port->line;
Russell King68ac64c2006-04-30 11:13:50 +01002496 struct uart_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002497
2498 BUG_ON(in_interrupt());
2499
2500 if (state->port != port)
2501 printk(KERN_ALERT "Removing wrong port: %p != %p\n",
2502 state->port, port);
2503
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002504 mutex_lock(&port_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002505
2506 /*
Russell King68ac64c2006-04-30 11:13:50 +01002507 * Mark the port "dead" - this prevents any opens from
2508 * succeeding while we shut down the port.
2509 */
2510 mutex_lock(&state->mutex);
2511 port->flags |= UPF_DEAD;
2512 mutex_unlock(&state->mutex);
2513
2514 /*
Greg Kroah-Hartmanaa4148c2005-06-20 21:15:16 -07002515 * Remove the devices from the tty layer
Linus Torvalds1da177e2005-04-16 15:20:36 -07002516 */
2517 tty_unregister_device(drv->tty_driver, port->line);
2518
Russell King68ac64c2006-04-30 11:13:50 +01002519 info = state->info;
2520 if (info && info->tty)
2521 tty_vhangup(info->tty);
2522
2523 /*
2524 * All users of this port should now be disconnected from
2525 * this driver, and the port shut down. We should be the
2526 * only thread fiddling with this port from now on.
2527 */
2528 state->info = NULL;
2529
2530 /*
2531 * Free the port IO and memory resources, if any.
2532 */
2533 if (port->type != PORT_UNKNOWN)
2534 port->ops->release_port(port);
2535
2536 /*
2537 * Indicate that there isn't a port here anymore.
2538 */
2539 port->type = PORT_UNKNOWN;
2540
2541 /*
2542 * Kill the tasklet, and free resources.
2543 */
2544 if (info) {
2545 tasklet_kill(&info->tlet);
2546 kfree(info);
2547 }
2548
Linus Torvalds1da177e2005-04-16 15:20:36 -07002549 state->port = NULL;
Arjan van de Venf392ecf2006-01-12 18:44:32 +00002550 mutex_unlock(&port_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002551
2552 return 0;
2553}
2554
2555/*
2556 * Are the two ports equivalent?
2557 */
2558int uart_match_port(struct uart_port *port1, struct uart_port *port2)
2559{
2560 if (port1->iotype != port2->iotype)
2561 return 0;
2562
2563 switch (port1->iotype) {
2564 case UPIO_PORT:
2565 return (port1->iobase == port2->iobase);
2566 case UPIO_HUB6:
2567 return (port1->iobase == port2->iobase) &&
2568 (port1->hub6 == port2->hub6);
2569 case UPIO_MEM:
Sergei Shtylyovd21b55d2006-08-28 19:49:03 +04002570 case UPIO_MEM32:
2571 case UPIO_AU:
2572 case UPIO_TSI:
Marc St-Jeanbeab6972007-05-06 14:48:45 -07002573 case UPIO_DWAPB:
Benjamin Herrenschmidt1624f002006-01-04 18:09:44 +00002574 return (port1->mapbase == port2->mapbase);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002575 }
2576 return 0;
2577}
2578EXPORT_SYMBOL(uart_match_port);
2579
Linus Torvalds1da177e2005-04-16 15:20:36 -07002580EXPORT_SYMBOL(uart_write_wakeup);
2581EXPORT_SYMBOL(uart_register_driver);
2582EXPORT_SYMBOL(uart_unregister_driver);
2583EXPORT_SYMBOL(uart_suspend_port);
2584EXPORT_SYMBOL(uart_resume_port);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002585EXPORT_SYMBOL(uart_add_one_port);
2586EXPORT_SYMBOL(uart_remove_one_port);
2587
2588MODULE_DESCRIPTION("Serial driver core");
2589MODULE_LICENSE("GPL");