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-rw-r--r--drivers/serial/serial_core.c2578
1 files changed, 0 insertions, 2578 deletions
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
deleted file mode 100644
index 460a72d91bb7..000000000000
--- a/drivers/serial/serial_core.c
+++ /dev/null
@@ -1,2578 +0,0 @@
1/*
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 */
25#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/proc_fs.h>
31#include <linux/seq_file.h>
32#include <linux/device.h>
33#include <linux/serial.h> /* for serial_state and serial_icounter_struct */
34#include <linux/serial_core.h>
35#include <linux/delay.h>
36#include <linux/mutex.h>
37
38#include <asm/irq.h>
39#include <asm/uaccess.h>
40
41/*
42 * This is used to lock changes in serial line configuration.
43 */
44static DEFINE_MUTEX(port_mutex);
45
46/*
47 * lockdep: port->lock is initialized in two places, but we
48 * want only one lock-class:
49 */
50static struct lock_class_key port_lock_key;
51
52#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
53
54#ifdef CONFIG_SERIAL_CORE_CONSOLE
55#define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line)
56#else
57#define uart_console(port) (0)
58#endif
59
60static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
61 struct ktermios *old_termios);
62static void __uart_wait_until_sent(struct uart_port *port, int timeout);
63static void uart_change_pm(struct uart_state *state, int pm_state);
64
65/*
66 * This routine is used by the interrupt handler to schedule processing in
67 * the software interrupt portion of the driver.
68 */
69void uart_write_wakeup(struct uart_port *port)
70{
71 struct uart_state *state = port->state;
72 /*
73 * This means you called this function _after_ the port was
74 * closed. No cookie for you.
75 */
76 BUG_ON(!state);
77 tasklet_schedule(&state->tlet);
78}
79
80static void uart_stop(struct tty_struct *tty)
81{
82 struct uart_state *state = tty->driver_data;
83 struct uart_port *port = state->uart_port;
84 unsigned long flags;
85
86 spin_lock_irqsave(&port->lock, flags);
87 port->ops->stop_tx(port);
88 spin_unlock_irqrestore(&port->lock, flags);
89}
90
91static void __uart_start(struct tty_struct *tty)
92{
93 struct uart_state *state = tty->driver_data;
94 struct uart_port *port = state->uart_port;
95
96 if (!uart_circ_empty(&state->xmit) && state->xmit.buf &&
97 !tty->stopped && !tty->hw_stopped)
98 port->ops->start_tx(port);
99}
100
101static void uart_start(struct tty_struct *tty)
102{
103 struct uart_state *state = tty->driver_data;
104 struct uart_port *port = state->uart_port;
105 unsigned long flags;
106
107 spin_lock_irqsave(&port->lock, flags);
108 __uart_start(tty);
109 spin_unlock_irqrestore(&port->lock, flags);
110}
111
112static void uart_tasklet_action(unsigned long data)
113{
114 struct uart_state *state = (struct uart_state *)data;
115 tty_wakeup(state->port.tty);
116}
117
118static inline void
119uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear)
120{
121 unsigned long flags;
122 unsigned int old;
123
124 spin_lock_irqsave(&port->lock, flags);
125 old = port->mctrl;
126 port->mctrl = (old & ~clear) | set;
127 if (old != port->mctrl)
128 port->ops->set_mctrl(port, port->mctrl);
129 spin_unlock_irqrestore(&port->lock, flags);
130}
131
132#define uart_set_mctrl(port, set) uart_update_mctrl(port, set, 0)
133#define uart_clear_mctrl(port, clear) uart_update_mctrl(port, 0, clear)
134
135/*
136 * Startup the port. This will be called once per open. All calls
137 * will be serialised by the per-port mutex.
138 */
139static int uart_startup(struct tty_struct *tty, struct uart_state *state, int init_hw)
140{
141 struct uart_port *uport = state->uart_port;
142 struct tty_port *port = &state->port;
143 unsigned long page;
144 int retval = 0;
145
146 if (port->flags & ASYNC_INITIALIZED)
147 return 0;
148
149 /*
150 * Set the TTY IO error marker - we will only clear this
151 * once we have successfully opened the port. Also set
152 * up the tty->alt_speed kludge
153 */
154 set_bit(TTY_IO_ERROR, &tty->flags);
155
156 if (uport->type == PORT_UNKNOWN)
157 return 0;
158
159 /*
160 * Initialise and allocate the transmit and temporary
161 * buffer.
162 */
163 if (!state->xmit.buf) {
164 /* This is protected by the per port mutex */
165 page = get_zeroed_page(GFP_KERNEL);
166 if (!page)
167 return -ENOMEM;
168
169 state->xmit.buf = (unsigned char *) page;
170 uart_circ_clear(&state->xmit);
171 }
172
173 retval = uport->ops->startup(uport);
174 if (retval == 0) {
175 if (init_hw) {
176 /*
177 * Initialise the hardware port settings.
178 */
179 uart_change_speed(tty, state, NULL);
180
181 /*
182 * Setup the RTS and DTR signals once the
183 * port is open and ready to respond.
184 */
185 if (tty->termios->c_cflag & CBAUD)
186 uart_set_mctrl(uport, TIOCM_RTS | TIOCM_DTR);
187 }
188
189 if (port->flags & ASYNC_CTS_FLOW) {
190 spin_lock_irq(&uport->lock);
191 if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS))
192 tty->hw_stopped = 1;
193 spin_unlock_irq(&uport->lock);
194 }
195
196 set_bit(ASYNCB_INITIALIZED, &port->flags);
197
198 clear_bit(TTY_IO_ERROR, &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 tty_struct *tty, struct uart_state *state)
213{
214 struct uart_port *uport = state->uart_port;
215 struct tty_port *port = &state->port;
216
217 /*
218 * Set the TTY IO error marker
219 */
220 if (tty)
221 set_bit(TTY_IO_ERROR, &tty->flags);
222
223 if (test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags)) {
224 /*
225 * Turn off DTR and RTS early.
226 */
227 if (!tty || (tty->termios->c_cflag & HUPCL))
228 uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
229
230 /*
231 * clear delta_msr_wait queue to avoid mem leaks: we may free
232 * the irq here so the queue might never be woken up. Note
233 * that we won't end up waiting on delta_msr_wait again since
234 * any outstanding file descriptors should be pointing at
235 * hung_up_tty_fops now.
236 */
237 wake_up_interruptible(&port->delta_msr_wait);
238
239 /*
240 * Free the IRQ and disable the port.
241 */
242 uport->ops->shutdown(uport);
243
244 /*
245 * Ensure that the IRQ handler isn't running on another CPU.
246 */
247 synchronize_irq(uport->irq);
248 }
249
250 /*
251 * kill off our tasklet
252 */
253 tasklet_kill(&state->tlet);
254
255 /*
256 * Free the transmit buffer page.
257 */
258 if (state->xmit.buf) {
259 free_page((unsigned long)state->xmit.buf);
260 state->xmit.buf = NULL;
261 }
262}
263
264/**
265 * uart_update_timeout - update per-port FIFO timeout.
266 * @port: uart_port structure describing the port
267 * @cflag: termios cflag value
268 * @baud: speed of the port
269 *
270 * Set the port FIFO timeout value. The @cflag value should
271 * reflect the actual hardware settings.
272 */
273void
274uart_update_timeout(struct uart_port *port, unsigned int cflag,
275 unsigned int baud)
276{
277 unsigned int bits;
278
279 /* byte size and parity */
280 switch (cflag & CSIZE) {
281 case CS5:
282 bits = 7;
283 break;
284 case CS6:
285 bits = 8;
286 break;
287 case CS7:
288 bits = 9;
289 break;
290 default:
291 bits = 10;
292 break; /* CS8 */
293 }
294
295 if (cflag & CSTOPB)
296 bits++;
297 if (cflag & PARENB)
298 bits++;
299
300 /*
301 * The total number of bits to be transmitted in the fifo.
302 */
303 bits = bits * port->fifosize;
304
305 /*
306 * Figure the timeout to send the above number of bits.
307 * Add .02 seconds of slop
308 */
309 port->timeout = (HZ * bits) / baud + HZ/50;
310}
311
312EXPORT_SYMBOL(uart_update_timeout);
313
314/**
315 * uart_get_baud_rate - return baud rate for a particular port
316 * @port: uart_port structure describing the port in question.
317 * @termios: desired termios settings.
318 * @old: old termios (or NULL)
319 * @min: minimum acceptable baud rate
320 * @max: maximum acceptable baud rate
321 *
322 * Decode the termios structure into a numeric baud rate,
323 * taking account of the magic 38400 baud rate (with spd_*
324 * flags), and mapping the %B0 rate to 9600 baud.
325 *
326 * If the new baud rate is invalid, try the old termios setting.
327 * If it's still invalid, we try 9600 baud.
328 *
329 * Update the @termios structure to reflect the baud rate
330 * we're actually going to be using. Don't do this for the case
331 * where B0 is requested ("hang up").
332 */
333unsigned int
334uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
335 struct ktermios *old, unsigned int min, unsigned int max)
336{
337 unsigned int try, baud, altbaud = 38400;
338 int hung_up = 0;
339 upf_t flags = port->flags & UPF_SPD_MASK;
340
341 if (flags == UPF_SPD_HI)
342 altbaud = 57600;
343 else if (flags == UPF_SPD_VHI)
344 altbaud = 115200;
345 else if (flags == UPF_SPD_SHI)
346 altbaud = 230400;
347 else if (flags == UPF_SPD_WARP)
348 altbaud = 460800;
349
350 for (try = 0; try < 2; try++) {
351 baud = tty_termios_baud_rate(termios);
352
353 /*
354 * The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
355 * Die! Die! Die!
356 */
357 if (baud == 38400)
358 baud = altbaud;
359
360 /*
361 * Special case: B0 rate.
362 */
363 if (baud == 0) {
364 hung_up = 1;
365 baud = 9600;
366 }
367
368 if (baud >= min && baud <= max)
369 return baud;
370
371 /*
372 * Oops, the quotient was zero. Try again with
373 * the old baud rate if possible.
374 */
375 termios->c_cflag &= ~CBAUD;
376 if (old) {
377 baud = tty_termios_baud_rate(old);
378 if (!hung_up)
379 tty_termios_encode_baud_rate(termios,
380 baud, baud);
381 old = NULL;
382 continue;
383 }
384
385 /*
386 * As a last resort, if the range cannot be met then clip to
387 * the nearest chip supported rate.
388 */
389 if (!hung_up) {
390 if (baud <= min)
391 tty_termios_encode_baud_rate(termios,
392 min + 1, min + 1);
393 else
394 tty_termios_encode_baud_rate(termios,
395 max - 1, max - 1);
396 }
397 }
398 /* Should never happen */
399 WARN_ON(1);
400 return 0;
401}
402
403EXPORT_SYMBOL(uart_get_baud_rate);
404
405/**
406 * uart_get_divisor - return uart clock divisor
407 * @port: uart_port structure describing the port.
408 * @baud: desired baud rate
409 *
410 * Calculate the uart clock divisor for the port.
411 */
412unsigned int
413uart_get_divisor(struct uart_port *port, unsigned int baud)
414{
415 unsigned int quot;
416
417 /*
418 * Old custom speed handling.
419 */
420 if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
421 quot = port->custom_divisor;
422 else
423 quot = (port->uartclk + (8 * baud)) / (16 * baud);
424
425 return quot;
426}
427
428EXPORT_SYMBOL(uart_get_divisor);
429
430/* FIXME: Consistent locking policy */
431static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
432 struct ktermios *old_termios)
433{
434 struct tty_port *port = &state->port;
435 struct uart_port *uport = state->uart_port;
436 struct ktermios *termios;
437
438 /*
439 * If we have no tty, termios, or the port does not exist,
440 * then we can't set the parameters for this port.
441 */
442 if (!tty || !tty->termios || uport->type == PORT_UNKNOWN)
443 return;
444
445 termios = tty->termios;
446
447 /*
448 * Set flags based on termios cflag
449 */
450 if (termios->c_cflag & CRTSCTS)
451 set_bit(ASYNCB_CTS_FLOW, &port->flags);
452 else
453 clear_bit(ASYNCB_CTS_FLOW, &port->flags);
454
455 if (termios->c_cflag & CLOCAL)
456 clear_bit(ASYNCB_CHECK_CD, &port->flags);
457 else
458 set_bit(ASYNCB_CHECK_CD, &port->flags);
459
460 uport->ops->set_termios(uport, termios, old_termios);
461}
462
463static inline int __uart_put_char(struct uart_port *port,
464 struct circ_buf *circ, unsigned char c)
465{
466 unsigned long flags;
467 int ret = 0;
468
469 if (!circ->buf)
470 return 0;
471
472 spin_lock_irqsave(&port->lock, flags);
473 if (uart_circ_chars_free(circ) != 0) {
474 circ->buf[circ->head] = c;
475 circ->head = (circ->head + 1) & (UART_XMIT_SIZE - 1);
476 ret = 1;
477 }
478 spin_unlock_irqrestore(&port->lock, flags);
479 return ret;
480}
481
482static int uart_put_char(struct tty_struct *tty, unsigned char ch)
483{
484 struct uart_state *state = tty->driver_data;
485
486 return __uart_put_char(state->uart_port, &state->xmit, ch);
487}
488
489static void uart_flush_chars(struct tty_struct *tty)
490{
491 uart_start(tty);
492}
493
494static int uart_write(struct tty_struct *tty,
495 const unsigned char *buf, int count)
496{
497 struct uart_state *state = tty->driver_data;
498 struct uart_port *port;
499 struct circ_buf *circ;
500 unsigned long flags;
501 int c, ret = 0;
502
503 /*
504 * This means you called this function _after_ the port was
505 * closed. No cookie for you.
506 */
507 if (!state) {
508 WARN_ON(1);
509 return -EL3HLT;
510 }
511
512 port = state->uart_port;
513 circ = &state->xmit;
514
515 if (!circ->buf)
516 return 0;
517
518 spin_lock_irqsave(&port->lock, flags);
519 while (1) {
520 c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE);
521 if (count < c)
522 c = count;
523 if (c <= 0)
524 break;
525 memcpy(circ->buf + circ->head, buf, c);
526 circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1);
527 buf += c;
528 count -= c;
529 ret += c;
530 }
531 spin_unlock_irqrestore(&port->lock, flags);
532
533 uart_start(tty);
534 return ret;
535}
536
537static int uart_write_room(struct tty_struct *tty)
538{
539 struct uart_state *state = tty->driver_data;
540 unsigned long flags;
541 int ret;
542
543 spin_lock_irqsave(&state->uart_port->lock, flags);
544 ret = uart_circ_chars_free(&state->xmit);
545 spin_unlock_irqrestore(&state->uart_port->lock, flags);
546 return ret;
547}
548
549static int uart_chars_in_buffer(struct tty_struct *tty)
550{
551 struct uart_state *state = tty->driver_data;
552 unsigned long flags;
553 int ret;
554
555 spin_lock_irqsave(&state->uart_port->lock, flags);
556 ret = uart_circ_chars_pending(&state->xmit);
557 spin_unlock_irqrestore(&state->uart_port->lock, flags);
558 return ret;
559}
560
561static void uart_flush_buffer(struct tty_struct *tty)
562{
563 struct uart_state *state = tty->driver_data;
564 struct uart_port *port;
565 unsigned long flags;
566
567 /*
568 * This means you called this function _after_ the port was
569 * closed. No cookie for you.
570 */
571 if (!state) {
572 WARN_ON(1);
573 return;
574 }
575
576 port = state->uart_port;
577 pr_debug("uart_flush_buffer(%d) called\n", tty->index);
578
579 spin_lock_irqsave(&port->lock, flags);
580 uart_circ_clear(&state->xmit);
581 if (port->ops->flush_buffer)
582 port->ops->flush_buffer(port);
583 spin_unlock_irqrestore(&port->lock, flags);
584 tty_wakeup(tty);
585}
586
587/*
588 * This function is used to send a high-priority XON/XOFF character to
589 * the device
590 */
591static void uart_send_xchar(struct tty_struct *tty, char ch)
592{
593 struct uart_state *state = tty->driver_data;
594 struct uart_port *port = state->uart_port;
595 unsigned long flags;
596
597 if (port->ops->send_xchar)
598 port->ops->send_xchar(port, ch);
599 else {
600 port->x_char = ch;
601 if (ch) {
602 spin_lock_irqsave(&port->lock, flags);
603 port->ops->start_tx(port);
604 spin_unlock_irqrestore(&port->lock, flags);
605 }
606 }
607}
608
609static void uart_throttle(struct tty_struct *tty)
610{
611 struct uart_state *state = tty->driver_data;
612
613 if (I_IXOFF(tty))
614 uart_send_xchar(tty, STOP_CHAR(tty));
615
616 if (tty->termios->c_cflag & CRTSCTS)
617 uart_clear_mctrl(state->uart_port, TIOCM_RTS);
618}
619
620static void uart_unthrottle(struct tty_struct *tty)
621{
622 struct uart_state *state = tty->driver_data;
623 struct uart_port *port = state->uart_port;
624
625 if (I_IXOFF(tty)) {
626 if (port->x_char)
627 port->x_char = 0;
628 else
629 uart_send_xchar(tty, START_CHAR(tty));
630 }
631
632 if (tty->termios->c_cflag & CRTSCTS)
633 uart_set_mctrl(port, TIOCM_RTS);
634}
635
636static int uart_get_info(struct uart_state *state,
637 struct serial_struct __user *retinfo)
638{
639 struct uart_port *uport = state->uart_port;
640 struct tty_port *port = &state->port;
641 struct serial_struct tmp;
642
643 memset(&tmp, 0, sizeof(tmp));
644
645 /* Ensure the state we copy is consistent and no hardware changes
646 occur as we go */
647 mutex_lock(&port->mutex);
648
649 tmp.type = uport->type;
650 tmp.line = uport->line;
651 tmp.port = uport->iobase;
652 if (HIGH_BITS_OFFSET)
653 tmp.port_high = (long) uport->iobase >> HIGH_BITS_OFFSET;
654 tmp.irq = uport->irq;
655 tmp.flags = uport->flags;
656 tmp.xmit_fifo_size = uport->fifosize;
657 tmp.baud_base = uport->uartclk / 16;
658 tmp.close_delay = port->close_delay / 10;
659 tmp.closing_wait = port->closing_wait == ASYNC_CLOSING_WAIT_NONE ?
660 ASYNC_CLOSING_WAIT_NONE :
661 port->closing_wait / 10;
662 tmp.custom_divisor = uport->custom_divisor;
663 tmp.hub6 = uport->hub6;
664 tmp.io_type = uport->iotype;
665 tmp.iomem_reg_shift = uport->regshift;
666 tmp.iomem_base = (void *)(unsigned long)uport->mapbase;
667
668 mutex_unlock(&port->mutex);
669
670 if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
671 return -EFAULT;
672 return 0;
673}
674
675static int uart_set_info(struct tty_struct *tty, struct uart_state *state,
676 struct serial_struct __user *newinfo)
677{
678 struct serial_struct new_serial;
679 struct uart_port *uport = state->uart_port;
680 struct tty_port *port = &state->port;
681 unsigned long new_port;
682 unsigned int change_irq, change_port, closing_wait;
683 unsigned int old_custom_divisor, close_delay;
684 upf_t old_flags, new_flags;
685 int retval = 0;
686
687 if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
688 return -EFAULT;
689
690 new_port = new_serial.port;
691 if (HIGH_BITS_OFFSET)
692 new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET;
693
694 new_serial.irq = irq_canonicalize(new_serial.irq);
695 close_delay = new_serial.close_delay * 10;
696 closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
697 ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
698
699 /*
700 * This semaphore protects port->count. It is also
701 * very useful to prevent opens. Also, take the
702 * port configuration semaphore to make sure that a
703 * module insertion/removal doesn't change anything
704 * under us.
705 */
706 mutex_lock(&port->mutex);
707
708 change_irq = !(uport->flags & UPF_FIXED_PORT)
709 && new_serial.irq != uport->irq;
710
711 /*
712 * Since changing the 'type' of the port changes its resource
713 * allocations, we should treat type changes the same as
714 * IO port changes.
715 */
716 change_port = !(uport->flags & UPF_FIXED_PORT)
717 && (new_port != uport->iobase ||
718 (unsigned long)new_serial.iomem_base != uport->mapbase ||
719 new_serial.hub6 != uport->hub6 ||
720 new_serial.io_type != uport->iotype ||
721 new_serial.iomem_reg_shift != uport->regshift ||
722 new_serial.type != uport->type);
723
724 old_flags = uport->flags;
725 new_flags = new_serial.flags;
726 old_custom_divisor = uport->custom_divisor;
727
728 if (!capable(CAP_SYS_ADMIN)) {
729 retval = -EPERM;
730 if (change_irq || change_port ||
731 (new_serial.baud_base != uport->uartclk / 16) ||
732 (close_delay != port->close_delay) ||
733 (closing_wait != port->closing_wait) ||
734 (new_serial.xmit_fifo_size &&
735 new_serial.xmit_fifo_size != uport->fifosize) ||
736 (((new_flags ^ old_flags) & ~UPF_USR_MASK) != 0))
737 goto exit;
738 uport->flags = ((uport->flags & ~UPF_USR_MASK) |
739 (new_flags & UPF_USR_MASK));
740 uport->custom_divisor = new_serial.custom_divisor;
741 goto check_and_exit;
742 }
743
744 /*
745 * Ask the low level driver to verify the settings.
746 */
747 if (uport->ops->verify_port)
748 retval = uport->ops->verify_port(uport, &new_serial);
749
750 if ((new_serial.irq >= nr_irqs) || (new_serial.irq < 0) ||
751 (new_serial.baud_base < 9600))
752 retval = -EINVAL;
753
754 if (retval)
755 goto exit;
756
757 if (change_port || change_irq) {
758 retval = -EBUSY;
759
760 /*
761 * Make sure that we are the sole user of this port.
762 */
763 if (tty_port_users(port) > 1)
764 goto exit;
765
766 /*
767 * We need to shutdown the serial port at the old
768 * port/type/irq combination.
769 */
770 uart_shutdown(tty, state);
771 }
772
773 if (change_port) {
774 unsigned long old_iobase, old_mapbase;
775 unsigned int old_type, old_iotype, old_hub6, old_shift;
776
777 old_iobase = uport->iobase;
778 old_mapbase = uport->mapbase;
779 old_type = uport->type;
780 old_hub6 = uport->hub6;
781 old_iotype = uport->iotype;
782 old_shift = uport->regshift;
783
784 /*
785 * Free and release old regions
786 */
787 if (old_type != PORT_UNKNOWN)
788 uport->ops->release_port(uport);
789
790 uport->iobase = new_port;
791 uport->type = new_serial.type;
792 uport->hub6 = new_serial.hub6;
793 uport->iotype = new_serial.io_type;
794 uport->regshift = new_serial.iomem_reg_shift;
795 uport->mapbase = (unsigned long)new_serial.iomem_base;
796
797 /*
798 * Claim and map the new regions
799 */
800 if (uport->type != PORT_UNKNOWN) {
801 retval = uport->ops->request_port(uport);
802 } else {
803 /* Always success - Jean II */
804 retval = 0;
805 }
806
807 /*
808 * If we fail to request resources for the
809 * new port, try to restore the old settings.
810 */
811 if (retval && old_type != PORT_UNKNOWN) {
812 uport->iobase = old_iobase;
813 uport->type = old_type;
814 uport->hub6 = old_hub6;
815 uport->iotype = old_iotype;
816 uport->regshift = old_shift;
817 uport->mapbase = old_mapbase;
818 retval = uport->ops->request_port(uport);
819 /*
820 * If we failed to restore the old settings,
821 * we fail like this.
822 */
823 if (retval)
824 uport->type = PORT_UNKNOWN;
825
826 /*
827 * We failed anyway.
828 */
829 retval = -EBUSY;
830 /* Added to return the correct error -Ram Gupta */
831 goto exit;
832 }
833 }
834
835 if (change_irq)
836 uport->irq = new_serial.irq;
837 if (!(uport->flags & UPF_FIXED_PORT))
838 uport->uartclk = new_serial.baud_base * 16;
839 uport->flags = (uport->flags & ~UPF_CHANGE_MASK) |
840 (new_flags & UPF_CHANGE_MASK);
841 uport->custom_divisor = new_serial.custom_divisor;
842 port->close_delay = close_delay;
843 port->closing_wait = closing_wait;
844 if (new_serial.xmit_fifo_size)
845 uport->fifosize = new_serial.xmit_fifo_size;
846 if (port->tty)
847 port->tty->low_latency =
848 (uport->flags & UPF_LOW_LATENCY) ? 1 : 0;
849
850 check_and_exit:
851 retval = 0;
852 if (uport->type == PORT_UNKNOWN)
853 goto exit;
854 if (port->flags & ASYNC_INITIALIZED) {
855 if (((old_flags ^ uport->flags) & UPF_SPD_MASK) ||
856 old_custom_divisor != uport->custom_divisor) {
857 /*
858 * If they're setting up a custom divisor or speed,
859 * instead of clearing it, then bitch about it. No
860 * need to rate-limit; it's CAP_SYS_ADMIN only.
861 */
862 if (uport->flags & UPF_SPD_MASK) {
863 char buf[64];
864 printk(KERN_NOTICE
865 "%s sets custom speed on %s. This "
866 "is deprecated.\n", current->comm,
867 tty_name(port->tty, buf));
868 }
869 uart_change_speed(tty, state, NULL);
870 }
871 } else
872 retval = uart_startup(tty, state, 1);
873 exit:
874 mutex_unlock(&port->mutex);
875 return retval;
876}
877
878/**
879 * uart_get_lsr_info - get line status register info
880 * @tty: tty associated with the UART
881 * @state: UART being queried
882 * @value: returned modem value
883 *
884 * Note: uart_ioctl protects us against hangups.
885 */
886static int uart_get_lsr_info(struct tty_struct *tty,
887 struct uart_state *state, unsigned int __user *value)
888{
889 struct uart_port *uport = state->uart_port;
890 unsigned int result;
891
892 result = uport->ops->tx_empty(uport);
893
894 /*
895 * If we're about to load something into the transmit
896 * register, we'll pretend the transmitter isn't empty to
897 * avoid a race condition (depending on when the transmit
898 * interrupt happens).
899 */
900 if (uport->x_char ||
901 ((uart_circ_chars_pending(&state->xmit) > 0) &&
902 !tty->stopped && !tty->hw_stopped))
903 result &= ~TIOCSER_TEMT;
904
905 return put_user(result, value);
906}
907
908static int uart_tiocmget(struct tty_struct *tty, struct file *file)
909{
910 struct uart_state *state = tty->driver_data;
911 struct tty_port *port = &state->port;
912 struct uart_port *uport = state->uart_port;
913 int result = -EIO;
914
915 mutex_lock(&port->mutex);
916 if ((!file || !tty_hung_up_p(file)) &&
917 !(tty->flags & (1 << TTY_IO_ERROR))) {
918 result = uport->mctrl;
919
920 spin_lock_irq(&uport->lock);
921 result |= uport->ops->get_mctrl(uport);
922 spin_unlock_irq(&uport->lock);
923 }
924 mutex_unlock(&port->mutex);
925
926 return result;
927}
928
929static int
930uart_tiocmset(struct tty_struct *tty, struct file *file,
931 unsigned int set, unsigned int clear)
932{
933 struct uart_state *state = tty->driver_data;
934 struct uart_port *uport = state->uart_port;
935 struct tty_port *port = &state->port;
936 int ret = -EIO;
937
938 mutex_lock(&port->mutex);
939 if ((!file || !tty_hung_up_p(file)) &&
940 !(tty->flags & (1 << TTY_IO_ERROR))) {
941 uart_update_mctrl(uport, set, clear);
942 ret = 0;
943 }
944 mutex_unlock(&port->mutex);
945 return ret;
946}
947
948static int uart_break_ctl(struct tty_struct *tty, int break_state)
949{
950 struct uart_state *state = tty->driver_data;
951 struct tty_port *port = &state->port;
952 struct uart_port *uport = state->uart_port;
953
954 mutex_lock(&port->mutex);
955
956 if (uport->type != PORT_UNKNOWN)
957 uport->ops->break_ctl(uport, break_state);
958
959 mutex_unlock(&port->mutex);
960 return 0;
961}
962
963static int uart_do_autoconfig(struct tty_struct *tty,struct uart_state *state)
964{
965 struct uart_port *uport = state->uart_port;
966 struct tty_port *port = &state->port;
967 int flags, ret;
968
969 if (!capable(CAP_SYS_ADMIN))
970 return -EPERM;
971
972 /*
973 * Take the per-port semaphore. This prevents count from
974 * changing, and hence any extra opens of the port while
975 * we're auto-configuring.
976 */
977 if (mutex_lock_interruptible(&port->mutex))
978 return -ERESTARTSYS;
979
980 ret = -EBUSY;
981 if (tty_port_users(port) == 1) {
982 uart_shutdown(tty, state);
983
984 /*
985 * If we already have a port type configured,
986 * we must release its resources.
987 */
988 if (uport->type != PORT_UNKNOWN)
989 uport->ops->release_port(uport);
990
991 flags = UART_CONFIG_TYPE;
992 if (uport->flags & UPF_AUTO_IRQ)
993 flags |= UART_CONFIG_IRQ;
994
995 /*
996 * This will claim the ports resources if
997 * a port is found.
998 */
999 uport->ops->config_port(uport, flags);
1000
1001 ret = uart_startup(tty, state, 1);
1002 }
1003 mutex_unlock(&port->mutex);
1004 return ret;
1005}
1006
1007/*
1008 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1009 * - mask passed in arg for lines of interest
1010 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1011 * Caller should use TIOCGICOUNT to see which one it was
1012 *
1013 * FIXME: This wants extracting into a common all driver implementation
1014 * of TIOCMWAIT using tty_port.
1015 */
1016static int
1017uart_wait_modem_status(struct uart_state *state, unsigned long arg)
1018{
1019 struct uart_port *uport = state->uart_port;
1020 struct tty_port *port = &state->port;
1021 DECLARE_WAITQUEUE(wait, current);
1022 struct uart_icount cprev, cnow;
1023 int ret;
1024
1025 /*
1026 * note the counters on entry
1027 */
1028 spin_lock_irq(&uport->lock);
1029 memcpy(&cprev, &uport->icount, sizeof(struct uart_icount));
1030
1031 /*
1032 * Force modem status interrupts on
1033 */
1034 uport->ops->enable_ms(uport);
1035 spin_unlock_irq(&uport->lock);
1036
1037 add_wait_queue(&port->delta_msr_wait, &wait);
1038 for (;;) {
1039 spin_lock_irq(&uport->lock);
1040 memcpy(&cnow, &uport->icount, sizeof(struct uart_icount));
1041 spin_unlock_irq(&uport->lock);
1042
1043 set_current_state(TASK_INTERRUPTIBLE);
1044
1045 if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1046 ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1047 ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
1048 ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
1049 ret = 0;
1050 break;
1051 }
1052
1053 schedule();
1054
1055 /* see if a signal did it */
1056 if (signal_pending(current)) {
1057 ret = -ERESTARTSYS;
1058 break;
1059 }
1060
1061 cprev = cnow;
1062 }
1063
1064 current->state = TASK_RUNNING;
1065 remove_wait_queue(&port->delta_msr_wait, &wait);
1066
1067 return ret;
1068}
1069
1070/*
1071 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1072 * Return: write counters to the user passed counter struct
1073 * NB: both 1->0 and 0->1 transitions are counted except for
1074 * RI where only 0->1 is counted.
1075 */
1076static int uart_get_icount(struct tty_struct *tty,
1077 struct serial_icounter_struct *icount)
1078{
1079 struct uart_state *state = tty->driver_data;
1080 struct uart_icount cnow;
1081 struct uart_port *uport = state->uart_port;
1082
1083 spin_lock_irq(&uport->lock);
1084 memcpy(&cnow, &uport->icount, sizeof(struct uart_icount));
1085 spin_unlock_irq(&uport->lock);
1086
1087 icount->cts = cnow.cts;
1088 icount->dsr = cnow.dsr;
1089 icount->rng = cnow.rng;
1090 icount->dcd = cnow.dcd;
1091 icount->rx = cnow.rx;
1092 icount->tx = cnow.tx;
1093 icount->frame = cnow.frame;
1094 icount->overrun = cnow.overrun;
1095 icount->parity = cnow.parity;
1096 icount->brk = cnow.brk;
1097 icount->buf_overrun = cnow.buf_overrun;
1098
1099 return 0;
1100}
1101
1102/*
1103 * Called via sys_ioctl. We can use spin_lock_irq() here.
1104 */
1105static int
1106uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
1107 unsigned long arg)
1108{
1109 struct uart_state *state = tty->driver_data;
1110 struct tty_port *port = &state->port;
1111 void __user *uarg = (void __user *)arg;
1112 int ret = -ENOIOCTLCMD;
1113
1114
1115 /*
1116 * These ioctls don't rely on the hardware to be present.
1117 */
1118 switch (cmd) {
1119 case TIOCGSERIAL:
1120 ret = uart_get_info(state, uarg);
1121 break;
1122
1123 case TIOCSSERIAL:
1124 ret = uart_set_info(tty, state, uarg);
1125 break;
1126
1127 case TIOCSERCONFIG:
1128 ret = uart_do_autoconfig(tty, state);
1129 break;
1130
1131 case TIOCSERGWILD: /* obsolete */
1132 case TIOCSERSWILD: /* obsolete */
1133 ret = 0;
1134 break;
1135 }
1136
1137 if (ret != -ENOIOCTLCMD)
1138 goto out;
1139
1140 if (tty->flags & (1 << TTY_IO_ERROR)) {
1141 ret = -EIO;
1142 goto out;
1143 }
1144
1145 /*
1146 * The following should only be used when hardware is present.
1147 */
1148 switch (cmd) {
1149 case TIOCMIWAIT:
1150 ret = uart_wait_modem_status(state, arg);
1151 break;
1152 }
1153
1154 if (ret != -ENOIOCTLCMD)
1155 goto out;
1156
1157 mutex_lock(&port->mutex);
1158
1159 if (tty_hung_up_p(filp)) {
1160 ret = -EIO;
1161 goto out_up;
1162 }
1163
1164 /*
1165 * All these rely on hardware being present and need to be
1166 * protected against the tty being hung up.
1167 */
1168 switch (cmd) {
1169 case TIOCSERGETLSR: /* Get line status register */
1170 ret = uart_get_lsr_info(tty, state, uarg);
1171 break;
1172
1173 default: {
1174 struct uart_port *uport = state->uart_port;
1175 if (uport->ops->ioctl)
1176 ret = uport->ops->ioctl(uport, cmd, arg);
1177 break;
1178 }
1179 }
1180out_up:
1181 mutex_unlock(&port->mutex);
1182out:
1183 return ret;
1184}
1185
1186static void uart_set_ldisc(struct tty_struct *tty)
1187{
1188 struct uart_state *state = tty->driver_data;
1189 struct uart_port *uport = state->uart_port;
1190
1191 if (uport->ops->set_ldisc)
1192 uport->ops->set_ldisc(uport, tty->termios->c_line);
1193}
1194
1195static void uart_set_termios(struct tty_struct *tty,
1196 struct ktermios *old_termios)
1197{
1198 struct uart_state *state = tty->driver_data;
1199 unsigned long flags;
1200 unsigned int cflag = tty->termios->c_cflag;
1201
1202
1203 /*
1204 * These are the bits that are used to setup various
1205 * flags in the low level driver. We can ignore the Bfoo
1206 * bits in c_cflag; c_[io]speed will always be set
1207 * appropriately by set_termios() in tty_ioctl.c
1208 */
1209#define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
1210 if ((cflag ^ old_termios->c_cflag) == 0 &&
1211 tty->termios->c_ospeed == old_termios->c_ospeed &&
1212 tty->termios->c_ispeed == old_termios->c_ispeed &&
1213 RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0) {
1214 return;
1215 }
1216
1217 uart_change_speed(tty, state, old_termios);
1218
1219 /* Handle transition to B0 status */
1220 if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD))
1221 uart_clear_mctrl(state->uart_port, TIOCM_RTS | TIOCM_DTR);
1222 /* Handle transition away from B0 status */
1223 else if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
1224 unsigned int mask = TIOCM_DTR;
1225 if (!(cflag & CRTSCTS) ||
1226 !test_bit(TTY_THROTTLED, &tty->flags))
1227 mask |= TIOCM_RTS;
1228 uart_set_mctrl(state->uart_port, mask);
1229 }
1230
1231 /* Handle turning off CRTSCTS */
1232 if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {
1233 spin_lock_irqsave(&state->uart_port->lock, flags);
1234 tty->hw_stopped = 0;
1235 __uart_start(tty);
1236 spin_unlock_irqrestore(&state->uart_port->lock, flags);
1237 }
1238 /* Handle turning on CRTSCTS */
1239 else if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
1240 spin_lock_irqsave(&state->uart_port->lock, flags);
1241 if (!(state->uart_port->ops->get_mctrl(state->uart_port) & TIOCM_CTS)) {
1242 tty->hw_stopped = 1;
1243 state->uart_port->ops->stop_tx(state->uart_port);
1244 }
1245 spin_unlock_irqrestore(&state->uart_port->lock, flags);
1246 }
1247#if 0
1248 /*
1249 * No need to wake up processes in open wait, since they
1250 * sample the CLOCAL flag once, and don't recheck it.
1251 * XXX It's not clear whether the current behavior is correct
1252 * or not. Hence, this may change.....
1253 */
1254 if (!(old_termios->c_cflag & CLOCAL) &&
1255 (tty->termios->c_cflag & CLOCAL))
1256 wake_up_interruptible(&state->uart_port.open_wait);
1257#endif
1258}
1259
1260/*
1261 * In 2.4.5, calls to this will be serialized via the BKL in
1262 * linux/drivers/char/tty_io.c:tty_release()
1263 * linux/drivers/char/tty_io.c:do_tty_handup()
1264 */
1265static void uart_close(struct tty_struct *tty, struct file *filp)
1266{
1267 struct uart_state *state = tty->driver_data;
1268 struct tty_port *port;
1269 struct uart_port *uport;
1270 unsigned long flags;
1271
1272 BUG_ON(!tty_locked());
1273
1274 if (!state)
1275 return;
1276
1277 uport = state->uart_port;
1278 port = &state->port;
1279
1280 pr_debug("uart_close(%d) called\n", uport->line);
1281
1282 mutex_lock(&port->mutex);
1283 spin_lock_irqsave(&port->lock, flags);
1284
1285 if (tty_hung_up_p(filp)) {
1286 spin_unlock_irqrestore(&port->lock, flags);
1287 goto done;
1288 }
1289
1290 if ((tty->count == 1) && (port->count != 1)) {
1291 /*
1292 * Uh, oh. tty->count is 1, which means that the tty
1293 * structure will be freed. port->count should always
1294 * be one in these conditions. If it's greater than
1295 * one, we've got real problems, since it means the
1296 * serial port won't be shutdown.
1297 */
1298 printk(KERN_ERR "uart_close: bad serial port count; tty->count is 1, "
1299 "port->count is %d\n", port->count);
1300 port->count = 1;
1301 }
1302 if (--port->count < 0) {
1303 printk(KERN_ERR "uart_close: bad serial port count for %s: %d\n",
1304 tty->name, port->count);
1305 port->count = 0;
1306 }
1307 if (port->count) {
1308 spin_unlock_irqrestore(&port->lock, flags);
1309 goto done;
1310 }
1311
1312 /*
1313 * Now we wait for the transmit buffer to clear; and we notify
1314 * the line discipline to only process XON/XOFF characters by
1315 * setting tty->closing.
1316 */
1317 tty->closing = 1;
1318 spin_unlock_irqrestore(&port->lock, flags);
1319
1320 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) {
1321 /*
1322 * hack: open-coded tty_wait_until_sent to avoid
1323 * recursive tty_lock
1324 */
1325 long timeout = msecs_to_jiffies(port->closing_wait);
1326 if (wait_event_interruptible_timeout(tty->write_wait,
1327 !tty_chars_in_buffer(tty), timeout) >= 0)
1328 __uart_wait_until_sent(uport, timeout);
1329 }
1330
1331 /*
1332 * At this point, we stop accepting input. To do this, we
1333 * disable the receive line status interrupts.
1334 */
1335 if (port->flags & ASYNC_INITIALIZED) {
1336 unsigned long flags;
1337 spin_lock_irqsave(&uport->lock, flags);
1338 uport->ops->stop_rx(uport);
1339 spin_unlock_irqrestore(&uport->lock, flags);
1340 /*
1341 * Before we drop DTR, make sure the UART transmitter
1342 * has completely drained; this is especially
1343 * important if there is a transmit FIFO!
1344 */
1345 __uart_wait_until_sent(uport, uport->timeout);
1346 }
1347
1348 uart_shutdown(tty, state);
1349 uart_flush_buffer(tty);
1350
1351 tty_ldisc_flush(tty);
1352
1353 tty_port_tty_set(port, NULL);
1354 spin_lock_irqsave(&port->lock, flags);
1355 tty->closing = 0;
1356
1357 if (port->blocked_open) {
1358 spin_unlock_irqrestore(&port->lock, flags);
1359 if (port->close_delay)
1360 msleep_interruptible(port->close_delay);
1361 spin_lock_irqsave(&port->lock, flags);
1362 } else if (!uart_console(uport)) {
1363 spin_unlock_irqrestore(&port->lock, flags);
1364 uart_change_pm(state, 3);
1365 spin_lock_irqsave(&port->lock, flags);
1366 }
1367
1368 /*
1369 * Wake up anyone trying to open this port.
1370 */
1371 clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);
1372 spin_unlock_irqrestore(&port->lock, flags);
1373 wake_up_interruptible(&port->open_wait);
1374
1375done:
1376 mutex_unlock(&port->mutex);
1377}
1378
1379static void __uart_wait_until_sent(struct uart_port *port, int timeout)
1380{
1381 unsigned long char_time, expire;
1382
1383 if (port->type == PORT_UNKNOWN || port->fifosize == 0)
1384 return;
1385
1386 /*
1387 * Set the check interval to be 1/5 of the estimated time to
1388 * send a single character, and make it at least 1. The check
1389 * interval should also be less than the timeout.
1390 *
1391 * Note: we have to use pretty tight timings here to satisfy
1392 * the NIST-PCTS.
1393 */
1394 char_time = (port->timeout - HZ/50) / port->fifosize;
1395 char_time = char_time / 5;
1396 if (char_time == 0)
1397 char_time = 1;
1398 if (timeout && timeout < char_time)
1399 char_time = timeout;
1400
1401 /*
1402 * If the transmitter hasn't cleared in twice the approximate
1403 * amount of time to send the entire FIFO, it probably won't
1404 * ever clear. This assumes the UART isn't doing flow
1405 * control, which is currently the case. Hence, if it ever
1406 * takes longer than port->timeout, this is probably due to a
1407 * UART bug of some kind. So, we clamp the timeout parameter at
1408 * 2*port->timeout.
1409 */
1410 if (timeout == 0 || timeout > 2 * port->timeout)
1411 timeout = 2 * port->timeout;
1412
1413 expire = jiffies + timeout;
1414
1415 pr_debug("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n",
1416 port->line, jiffies, expire);
1417
1418 /*
1419 * Check whether the transmitter is empty every 'char_time'.
1420 * 'timeout' / 'expire' give us the maximum amount of time
1421 * we wait.
1422 */
1423 while (!port->ops->tx_empty(port)) {
1424 msleep_interruptible(jiffies_to_msecs(char_time));
1425 if (signal_pending(current))
1426 break;
1427 if (time_after(jiffies, expire))
1428 break;
1429 }
1430 set_current_state(TASK_RUNNING); /* might not be needed */
1431}
1432
1433static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
1434{
1435 struct uart_state *state = tty->driver_data;
1436 struct uart_port *port = state->uart_port;
1437
1438 tty_lock();
1439 __uart_wait_until_sent(port, timeout);
1440 tty_unlock();
1441}
1442
1443/*
1444 * This is called with the BKL held in
1445 * linux/drivers/char/tty_io.c:do_tty_hangup()
1446 * We're called from the eventd thread, so we can sleep for
1447 * a _short_ time only.
1448 */
1449static void uart_hangup(struct tty_struct *tty)
1450{
1451 struct uart_state *state = tty->driver_data;
1452 struct tty_port *port = &state->port;
1453 unsigned long flags;
1454
1455 BUG_ON(!tty_locked());
1456 pr_debug("uart_hangup(%d)\n", state->uart_port->line);
1457
1458 mutex_lock(&port->mutex);
1459 if (port->flags & ASYNC_NORMAL_ACTIVE) {
1460 uart_flush_buffer(tty);
1461 uart_shutdown(tty, state);
1462 spin_lock_irqsave(&port->lock, flags);
1463 port->count = 0;
1464 clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);
1465 spin_unlock_irqrestore(&port->lock, flags);
1466 tty_port_tty_set(port, NULL);
1467 wake_up_interruptible(&port->open_wait);
1468 wake_up_interruptible(&port->delta_msr_wait);
1469 }
1470 mutex_unlock(&port->mutex);
1471}
1472
1473/**
1474 * uart_update_termios - update the terminal hw settings
1475 * @tty: tty associated with UART
1476 * @state: UART to update
1477 *
1478 * Copy across the serial console cflag setting into the termios settings
1479 * for the initial open of the port. This allows continuity between the
1480 * kernel settings, and the settings init adopts when it opens the port
1481 * for the first time.
1482 */
1483static void uart_update_termios(struct tty_struct *tty,
1484 struct uart_state *state)
1485{
1486 struct uart_port *port = state->uart_port;
1487
1488 if (uart_console(port) && port->cons->cflag) {
1489 tty->termios->c_cflag = port->cons->cflag;
1490 port->cons->cflag = 0;
1491 }
1492
1493 /*
1494 * If the device failed to grab its irq resources,
1495 * or some other error occurred, don't try to talk
1496 * to the port hardware.
1497 */
1498 if (!(tty->flags & (1 << TTY_IO_ERROR))) {
1499 /*
1500 * Make termios settings take effect.
1501 */
1502 uart_change_speed(tty, state, NULL);
1503
1504 /*
1505 * And finally enable the RTS and DTR signals.
1506 */
1507 if (tty->termios->c_cflag & CBAUD)
1508 uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1509 }
1510}
1511
1512static int uart_carrier_raised(struct tty_port *port)
1513{
1514 struct uart_state *state = container_of(port, struct uart_state, port);
1515 struct uart_port *uport = state->uart_port;
1516 int mctrl;
1517 spin_lock_irq(&uport->lock);
1518 uport->ops->enable_ms(uport);
1519 mctrl = uport->ops->get_mctrl(uport);
1520 spin_unlock_irq(&uport->lock);
1521 if (mctrl & TIOCM_CAR)
1522 return 1;
1523 return 0;
1524}
1525
1526static void uart_dtr_rts(struct tty_port *port, int onoff)
1527{
1528 struct uart_state *state = container_of(port, struct uart_state, port);
1529 struct uart_port *uport = state->uart_port;
1530
1531 if (onoff) {
1532 uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
1533
1534 /*
1535 * If this is the first open to succeed,
1536 * adjust things to suit.
1537 */
1538 if (!test_and_set_bit(ASYNCB_NORMAL_ACTIVE, &port->flags))
1539 uart_update_termios(port->tty, state);
1540 }
1541 else
1542 uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
1543}
1544
1545static struct uart_state *uart_get(struct uart_driver *drv, int line)
1546{
1547 struct uart_state *state;
1548 struct tty_port *port;
1549 int ret = 0;
1550
1551 state = drv->state + line;
1552 port = &state->port;
1553 if (mutex_lock_interruptible(&port->mutex)) {
1554 ret = -ERESTARTSYS;
1555 goto err;
1556 }
1557
1558 port->count++;
1559 if (!state->uart_port || state->uart_port->flags & UPF_DEAD) {
1560 ret = -ENXIO;
1561 goto err_unlock;
1562 }
1563 return state;
1564
1565 err_unlock:
1566 port->count--;
1567 mutex_unlock(&port->mutex);
1568 err:
1569 return ERR_PTR(ret);
1570}
1571
1572/*
1573 * calls to uart_open are serialised by the BKL in
1574 * fs/char_dev.c:chrdev_open()
1575 * Note that if this fails, then uart_close() _will_ be called.
1576 *
1577 * In time, we want to scrap the "opening nonpresent ports"
1578 * behaviour and implement an alternative way for setserial
1579 * to set base addresses/ports/types. This will allow us to
1580 * get rid of a certain amount of extra tests.
1581 */
1582static int uart_open(struct tty_struct *tty, struct file *filp)
1583{
1584 struct uart_driver *drv = (struct uart_driver *)tty->driver->driver_state;
1585 struct uart_state *state;
1586 struct tty_port *port;
1587 int retval, line = tty->index;
1588
1589 BUG_ON(!tty_locked());
1590 pr_debug("uart_open(%d) called\n", line);
1591
1592 /*
1593 * tty->driver->num won't change, so we won't fail here with
1594 * tty->driver_data set to something non-NULL (and therefore
1595 * we won't get caught by uart_close()).
1596 */
1597 retval = -ENODEV;
1598 if (line >= tty->driver->num)
1599 goto fail;
1600
1601 /*
1602 * We take the semaphore inside uart_get to guarantee that we won't
1603 * be re-entered while allocating the state structure, or while we
1604 * request any IRQs that the driver may need. This also has the nice
1605 * side-effect that it delays the action of uart_hangup, so we can
1606 * guarantee that state->port.tty will always contain something
1607 * reasonable.
1608 */
1609 state = uart_get(drv, line);
1610 if (IS_ERR(state)) {
1611 retval = PTR_ERR(state);
1612 goto fail;
1613 }
1614 port = &state->port;
1615
1616 /*
1617 * Once we set tty->driver_data here, we are guaranteed that
1618 * uart_close() will decrement the driver module use count.
1619 * Any failures from here onwards should not touch the count.
1620 */
1621 tty->driver_data = state;
1622 state->uart_port->state = state;
1623 tty->low_latency = (state->uart_port->flags & UPF_LOW_LATENCY) ? 1 : 0;
1624 tty->alt_speed = 0;
1625 tty_port_tty_set(port, tty);
1626
1627 /*
1628 * If the port is in the middle of closing, bail out now.
1629 */
1630 if (tty_hung_up_p(filp)) {
1631 retval = -EAGAIN;
1632 port->count--;
1633 mutex_unlock(&port->mutex);
1634 goto fail;
1635 }
1636
1637 /*
1638 * Make sure the device is in D0 state.
1639 */
1640 if (port->count == 1)
1641 uart_change_pm(state, 0);
1642
1643 /*
1644 * Start up the serial port.
1645 */
1646 retval = uart_startup(tty, state, 0);
1647
1648 /*
1649 * If we succeeded, wait until the port is ready.
1650 */
1651 mutex_unlock(&port->mutex);
1652 if (retval == 0)
1653 retval = tty_port_block_til_ready(port, tty, filp);
1654
1655fail:
1656 return retval;
1657}
1658
1659static const char *uart_type(struct uart_port *port)
1660{
1661 const char *str = NULL;
1662
1663 if (port->ops->type)
1664 str = port->ops->type(port);
1665
1666 if (!str)
1667 str = "unknown";
1668
1669 return str;
1670}
1671
1672#ifdef CONFIG_PROC_FS
1673
1674static void uart_line_info(struct seq_file *m, struct uart_driver *drv, int i)
1675{
1676 struct uart_state *state = drv->state + i;
1677 struct tty_port *port = &state->port;
1678 int pm_state;
1679 struct uart_port *uport = state->uart_port;
1680 char stat_buf[32];
1681 unsigned int status;
1682 int mmio;
1683
1684 if (!uport)
1685 return;
1686
1687 mmio = uport->iotype >= UPIO_MEM;
1688 seq_printf(m, "%d: uart:%s %s%08llX irq:%d",
1689 uport->line, uart_type(uport),
1690 mmio ? "mmio:0x" : "port:",
1691 mmio ? (unsigned long long)uport->mapbase
1692 : (unsigned long long)uport->iobase,
1693 uport->irq);
1694
1695 if (uport->type == PORT_UNKNOWN) {
1696 seq_putc(m, '\n');
1697 return;
1698 }
1699
1700 if (capable(CAP_SYS_ADMIN)) {
1701 mutex_lock(&port->mutex);
1702 pm_state = state->pm_state;
1703 if (pm_state)
1704 uart_change_pm(state, 0);
1705 spin_lock_irq(&uport->lock);
1706 status = uport->ops->get_mctrl(uport);
1707 spin_unlock_irq(&uport->lock);
1708 if (pm_state)
1709 uart_change_pm(state, pm_state);
1710 mutex_unlock(&port->mutex);
1711
1712 seq_printf(m, " tx:%d rx:%d",
1713 uport->icount.tx, uport->icount.rx);
1714 if (uport->icount.frame)
1715 seq_printf(m, " fe:%d",
1716 uport->icount.frame);
1717 if (uport->icount.parity)
1718 seq_printf(m, " pe:%d",
1719 uport->icount.parity);
1720 if (uport->icount.brk)
1721 seq_printf(m, " brk:%d",
1722 uport->icount.brk);
1723 if (uport->icount.overrun)
1724 seq_printf(m, " oe:%d",
1725 uport->icount.overrun);
1726
1727#define INFOBIT(bit, str) \
1728 if (uport->mctrl & (bit)) \
1729 strncat(stat_buf, (str), sizeof(stat_buf) - \
1730 strlen(stat_buf) - 2)
1731#define STATBIT(bit, str) \
1732 if (status & (bit)) \
1733 strncat(stat_buf, (str), sizeof(stat_buf) - \
1734 strlen(stat_buf) - 2)
1735
1736 stat_buf[0] = '\0';
1737 stat_buf[1] = '\0';
1738 INFOBIT(TIOCM_RTS, "|RTS");
1739 STATBIT(TIOCM_CTS, "|CTS");
1740 INFOBIT(TIOCM_DTR, "|DTR");
1741 STATBIT(TIOCM_DSR, "|DSR");
1742 STATBIT(TIOCM_CAR, "|CD");
1743 STATBIT(TIOCM_RNG, "|RI");
1744 if (stat_buf[0])
1745 stat_buf[0] = ' ';
1746
1747 seq_puts(m, stat_buf);
1748 }
1749 seq_putc(m, '\n');
1750#undef STATBIT
1751#undef INFOBIT
1752}
1753
1754static int uart_proc_show(struct seq_file *m, void *v)
1755{
1756 struct tty_driver *ttydrv = m->private;
1757 struct uart_driver *drv = ttydrv->driver_state;
1758 int i;
1759
1760 seq_printf(m, "serinfo:1.0 driver%s%s revision:%s\n",
1761 "", "", "");
1762 for (i = 0; i < drv->nr; i++)
1763 uart_line_info(m, drv, i);
1764 return 0;
1765}
1766
1767static int uart_proc_open(struct inode *inode, struct file *file)
1768{
1769 return single_open(file, uart_proc_show, PDE(inode)->data);
1770}
1771
1772static const struct file_operations uart_proc_fops = {
1773 .owner = THIS_MODULE,
1774 .open = uart_proc_open,
1775 .read = seq_read,
1776 .llseek = seq_lseek,
1777 .release = single_release,
1778};
1779#endif
1780
1781#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL)
1782/*
1783 * uart_console_write - write a console message to a serial port
1784 * @port: the port to write the message
1785 * @s: array of characters
1786 * @count: number of characters in string to write
1787 * @write: function to write character to port
1788 */
1789void uart_console_write(struct uart_port *port, const char *s,
1790 unsigned int count,
1791 void (*putchar)(struct uart_port *, int))
1792{
1793 unsigned int i;
1794
1795 for (i = 0; i < count; i++, s++) {
1796 if (*s == '\n')
1797 putchar(port, '\r');
1798 putchar(port, *s);
1799 }
1800}
1801EXPORT_SYMBOL_GPL(uart_console_write);
1802
1803/*
1804 * Check whether an invalid uart number has been specified, and
1805 * if so, search for the first available port that does have
1806 * console support.
1807 */
1808struct uart_port * __init
1809uart_get_console(struct uart_port *ports, int nr, struct console *co)
1810{
1811 int idx = co->index;
1812
1813 if (idx < 0 || idx >= nr || (ports[idx].iobase == 0 &&
1814 ports[idx].membase == NULL))
1815 for (idx = 0; idx < nr; idx++)
1816 if (ports[idx].iobase != 0 ||
1817 ports[idx].membase != NULL)
1818 break;
1819
1820 co->index = idx;
1821
1822 return ports + idx;
1823}
1824
1825/**
1826 * uart_parse_options - Parse serial port baud/parity/bits/flow contro.
1827 * @options: pointer to option string
1828 * @baud: pointer to an 'int' variable for the baud rate.
1829 * @parity: pointer to an 'int' variable for the parity.
1830 * @bits: pointer to an 'int' variable for the number of data bits.
1831 * @flow: pointer to an 'int' variable for the flow control character.
1832 *
1833 * uart_parse_options decodes a string containing the serial console
1834 * options. The format of the string is <baud><parity><bits><flow>,
1835 * eg: 115200n8r
1836 */
1837void
1838uart_parse_options(char *options, int *baud, int *parity, int *bits, int *flow)
1839{
1840 char *s = options;
1841
1842 *baud = simple_strtoul(s, NULL, 10);
1843 while (*s >= '0' && *s <= '9')
1844 s++;
1845 if (*s)
1846 *parity = *s++;
1847 if (*s)
1848 *bits = *s++ - '0';
1849 if (*s)
1850 *flow = *s;
1851}
1852EXPORT_SYMBOL_GPL(uart_parse_options);
1853
1854struct baud_rates {
1855 unsigned int rate;
1856 unsigned int cflag;
1857};
1858
1859static const struct baud_rates baud_rates[] = {
1860 { 921600, B921600 },
1861 { 460800, B460800 },
1862 { 230400, B230400 },
1863 { 115200, B115200 },
1864 { 57600, B57600 },
1865 { 38400, B38400 },
1866 { 19200, B19200 },
1867 { 9600, B9600 },
1868 { 4800, B4800 },
1869 { 2400, B2400 },
1870 { 1200, B1200 },
1871 { 0, B38400 }
1872};
1873
1874/**
1875 * uart_set_options - setup the serial console parameters
1876 * @port: pointer to the serial ports uart_port structure
1877 * @co: console pointer
1878 * @baud: baud rate
1879 * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
1880 * @bits: number of data bits
1881 * @flow: flow control character - 'r' (rts)
1882 */
1883int
1884uart_set_options(struct uart_port *port, struct console *co,
1885 int baud, int parity, int bits, int flow)
1886{
1887 struct ktermios termios;
1888 static struct ktermios dummy;
1889 int i;
1890
1891 /*
1892 * Ensure that the serial console lock is initialised
1893 * early.
1894 */
1895 spin_lock_init(&port->lock);
1896 lockdep_set_class(&port->lock, &port_lock_key);
1897
1898 memset(&termios, 0, sizeof(struct ktermios));
1899
1900 termios.c_cflag = CREAD | HUPCL | CLOCAL;
1901
1902 /*
1903 * Construct a cflag setting.
1904 */
1905 for (i = 0; baud_rates[i].rate; i++)
1906 if (baud_rates[i].rate <= baud)
1907 break;
1908
1909 termios.c_cflag |= baud_rates[i].cflag;
1910
1911 if (bits == 7)
1912 termios.c_cflag |= CS7;
1913 else
1914 termios.c_cflag |= CS8;
1915
1916 switch (parity) {
1917 case 'o': case 'O':
1918 termios.c_cflag |= PARODD;
1919 /*fall through*/
1920 case 'e': case 'E':
1921 termios.c_cflag |= PARENB;
1922 break;
1923 }
1924
1925 if (flow == 'r')
1926 termios.c_cflag |= CRTSCTS;
1927
1928 /*
1929 * some uarts on other side don't support no flow control.
1930 * So we set * DTR in host uart to make them happy
1931 */
1932 port->mctrl |= TIOCM_DTR;
1933
1934 port->ops->set_termios(port, &termios, &dummy);
1935 /*
1936 * Allow the setting of the UART parameters with a NULL console
1937 * too:
1938 */
1939 if (co)
1940 co->cflag = termios.c_cflag;
1941
1942 return 0;
1943}
1944EXPORT_SYMBOL_GPL(uart_set_options);
1945#endif /* CONFIG_SERIAL_CORE_CONSOLE */
1946
1947static void uart_change_pm(struct uart_state *state, int pm_state)
1948{
1949 struct uart_port *port = state->uart_port;
1950
1951 if (state->pm_state != pm_state) {
1952 if (port->ops->pm)
1953 port->ops->pm(port, pm_state, state->pm_state);
1954 state->pm_state = pm_state;
1955 }
1956}
1957
1958struct uart_match {
1959 struct uart_port *port;
1960 struct uart_driver *driver;
1961};
1962
1963static int serial_match_port(struct device *dev, void *data)
1964{
1965 struct uart_match *match = data;
1966 struct tty_driver *tty_drv = match->driver->tty_driver;
1967 dev_t devt = MKDEV(tty_drv->major, tty_drv->minor_start) +
1968 match->port->line;
1969
1970 return dev->devt == devt; /* Actually, only one tty per port */
1971}
1972
1973int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
1974{
1975 struct uart_state *state = drv->state + uport->line;
1976 struct tty_port *port = &state->port;
1977 struct device *tty_dev;
1978 struct uart_match match = {uport, drv};
1979 struct tty_struct *tty;
1980
1981 mutex_lock(&port->mutex);
1982
1983 /* Must be inside the mutex lock until we convert to tty_port */
1984 tty = port->tty;
1985
1986 tty_dev = device_find_child(uport->dev, &match, serial_match_port);
1987 if (device_may_wakeup(tty_dev)) {
1988 if (!enable_irq_wake(uport->irq))
1989 uport->irq_wake = 1;
1990 put_device(tty_dev);
1991 mutex_unlock(&port->mutex);
1992 return 0;
1993 }
1994 if (console_suspend_enabled || !uart_console(uport))
1995 uport->suspended = 1;
1996
1997 if (port->flags & ASYNC_INITIALIZED) {
1998 const struct uart_ops *ops = uport->ops;
1999 int tries;
2000
2001 if (console_suspend_enabled || !uart_console(uport)) {
2002 set_bit(ASYNCB_SUSPENDED, &port->flags);
2003 clear_bit(ASYNCB_INITIALIZED, &port->flags);
2004
2005 spin_lock_irq(&uport->lock);
2006 ops->stop_tx(uport);
2007 ops->set_mctrl(uport, 0);
2008 ops->stop_rx(uport);
2009 spin_unlock_irq(&uport->lock);
2010 }
2011
2012 /*
2013 * Wait for the transmitter to empty.
2014 */
2015 for (tries = 3; !ops->tx_empty(uport) && tries; tries--)
2016 msleep(10);
2017 if (!tries)
2018 printk(KERN_ERR "%s%s%s%d: Unable to drain "
2019 "transmitter\n",
2020 uport->dev ? dev_name(uport->dev) : "",
2021 uport->dev ? ": " : "",
2022 drv->dev_name,
2023 drv->tty_driver->name_base + uport->line);
2024
2025 if (console_suspend_enabled || !uart_console(uport))
2026 ops->shutdown(uport);
2027 }
2028
2029 /*
2030 * Disable the console device before suspending.
2031 */
2032 if (console_suspend_enabled && uart_console(uport))
2033 console_stop(uport->cons);
2034
2035 if (console_suspend_enabled || !uart_console(uport))
2036 uart_change_pm(state, 3);
2037
2038 mutex_unlock(&port->mutex);
2039
2040 return 0;
2041}
2042
2043int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
2044{
2045 struct uart_state *state = drv->state + uport->line;
2046 struct tty_port *port = &state->port;
2047 struct device *tty_dev;
2048 struct uart_match match = {uport, drv};
2049 struct ktermios termios;
2050
2051 mutex_lock(&port->mutex);
2052
2053 tty_dev = device_find_child(uport->dev, &match, serial_match_port);
2054 if (!uport->suspended && device_may_wakeup(tty_dev)) {
2055 if (uport->irq_wake) {
2056 disable_irq_wake(uport->irq);
2057 uport->irq_wake = 0;
2058 }
2059 mutex_unlock(&port->mutex);
2060 return 0;
2061 }
2062 uport->suspended = 0;
2063
2064 /*
2065 * Re-enable the console device after suspending.
2066 */
2067 if (console_suspend_enabled && uart_console(uport)) {
2068 /*
2069 * First try to use the console cflag setting.
2070 */
2071 memset(&termios, 0, sizeof(struct ktermios));
2072 termios.c_cflag = uport->cons->cflag;
2073
2074 /*
2075 * If that's unset, use the tty termios setting.
2076 */
2077 if (port->tty && port->tty->termios && termios.c_cflag == 0)
2078 termios = *(port->tty->termios);
2079
2080 uart_change_pm(state, 0);
2081 uport->ops->set_termios(uport, &termios, NULL);
2082 console_start(uport->cons);
2083 }
2084
2085 if (port->flags & ASYNC_SUSPENDED) {
2086 const struct uart_ops *ops = uport->ops;
2087 int ret;
2088
2089 uart_change_pm(state, 0);
2090 spin_lock_irq(&uport->lock);
2091 ops->set_mctrl(uport, 0);
2092 spin_unlock_irq(&uport->lock);
2093 if (console_suspend_enabled || !uart_console(uport)) {
2094 /* Protected by port mutex for now */
2095 struct tty_struct *tty = port->tty;
2096 ret = ops->startup(uport);
2097 if (ret == 0) {
2098 if (tty)
2099 uart_change_speed(tty, state, NULL);
2100 spin_lock_irq(&uport->lock);
2101 ops->set_mctrl(uport, uport->mctrl);
2102 ops->start_tx(uport);
2103 spin_unlock_irq(&uport->lock);
2104 set_bit(ASYNCB_INITIALIZED, &port->flags);
2105 } else {
2106 /*
2107 * Failed to resume - maybe hardware went away?
2108 * Clear the "initialized" flag so we won't try
2109 * to call the low level drivers shutdown method.
2110 */
2111 uart_shutdown(tty, state);
2112 }
2113 }
2114
2115 clear_bit(ASYNCB_SUSPENDED, &port->flags);
2116 }
2117
2118 mutex_unlock(&port->mutex);
2119
2120 return 0;
2121}
2122
2123static inline void
2124uart_report_port(struct uart_driver *drv, struct uart_port *port)
2125{
2126 char address[64];
2127
2128 switch (port->iotype) {
2129 case UPIO_PORT:
2130 snprintf(address, sizeof(address), "I/O 0x%lx", port->iobase);
2131 break;
2132 case UPIO_HUB6:
2133 snprintf(address, sizeof(address),
2134 "I/O 0x%lx offset 0x%x", port->iobase, port->hub6);
2135 break;
2136 case UPIO_MEM:
2137 case UPIO_MEM32:
2138 case UPIO_AU:
2139 case UPIO_TSI:
2140 case UPIO_DWAPB:
2141 case UPIO_DWAPB32:
2142 snprintf(address, sizeof(address),
2143 "MMIO 0x%llx", (unsigned long long)port->mapbase);
2144 break;
2145 default:
2146 strlcpy(address, "*unknown*", sizeof(address));
2147 break;
2148 }
2149
2150 printk(KERN_INFO "%s%s%s%d at %s (irq = %d) is a %s\n",
2151 port->dev ? dev_name(port->dev) : "",
2152 port->dev ? ": " : "",
2153 drv->dev_name,
2154 drv->tty_driver->name_base + port->line,
2155 address, port->irq, uart_type(port));
2156}
2157
2158static void
2159uart_configure_port(struct uart_driver *drv, struct uart_state *state,
2160 struct uart_port *port)
2161{
2162 unsigned int flags;
2163
2164 /*
2165 * If there isn't a port here, don't do anything further.
2166 */
2167 if (!port->iobase && !port->mapbase && !port->membase)
2168 return;
2169
2170 /*
2171 * Now do the auto configuration stuff. Note that config_port
2172 * is expected to claim the resources and map the port for us.
2173 */
2174 flags = 0;
2175 if (port->flags & UPF_AUTO_IRQ)
2176 flags |= UART_CONFIG_IRQ;
2177 if (port->flags & UPF_BOOT_AUTOCONF) {
2178 if (!(port->flags & UPF_FIXED_TYPE)) {
2179 port->type = PORT_UNKNOWN;
2180 flags |= UART_CONFIG_TYPE;
2181 }
2182 port->ops->config_port(port, flags);
2183 }
2184
2185 if (port->type != PORT_UNKNOWN) {
2186 unsigned long flags;
2187
2188 uart_report_port(drv, port);
2189
2190 /* Power up port for set_mctrl() */
2191 uart_change_pm(state, 0);
2192
2193 /*
2194 * Ensure that the modem control lines are de-activated.
2195 * keep the DTR setting that is set in uart_set_options()
2196 * We probably don't need a spinlock around this, but
2197 */
2198 spin_lock_irqsave(&port->lock, flags);
2199 port->ops->set_mctrl(port, port->mctrl & TIOCM_DTR);
2200 spin_unlock_irqrestore(&port->lock, flags);
2201
2202 /*
2203 * If this driver supports console, and it hasn't been
2204 * successfully registered yet, try to re-register it.
2205 * It may be that the port was not available.
2206 */
2207 if (port->cons && !(port->cons->flags & CON_ENABLED))
2208 register_console(port->cons);
2209
2210 /*
2211 * Power down all ports by default, except the
2212 * console if we have one.
2213 */
2214 if (!uart_console(port))
2215 uart_change_pm(state, 3);
2216 }
2217}
2218
2219#ifdef CONFIG_CONSOLE_POLL
2220
2221static int uart_poll_init(struct tty_driver *driver, int line, char *options)
2222{
2223 struct uart_driver *drv = driver->driver_state;
2224 struct uart_state *state = drv->state + line;
2225 struct uart_port *port;
2226 int baud = 9600;
2227 int bits = 8;
2228 int parity = 'n';
2229 int flow = 'n';
2230
2231 if (!state || !state->uart_port)
2232 return -1;
2233
2234 port = state->uart_port;
2235 if (!(port->ops->poll_get_char && port->ops->poll_put_char))
2236 return -1;
2237
2238 if (options) {
2239 uart_parse_options(options, &baud, &parity, &bits, &flow);
2240 return uart_set_options(port, NULL, baud, parity, bits, flow);
2241 }
2242
2243 return 0;
2244}
2245
2246static int uart_poll_get_char(struct tty_driver *driver, int line)
2247{
2248 struct uart_driver *drv = driver->driver_state;
2249 struct uart_state *state = drv->state + line;
2250 struct uart_port *port;
2251
2252 if (!state || !state->uart_port)
2253 return -1;
2254
2255 port = state->uart_port;
2256 return port->ops->poll_get_char(port);
2257}
2258
2259static void uart_poll_put_char(struct tty_driver *driver, int line, char ch)
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->uart_port)
2266 return;
2267
2268 port = state->uart_port;
2269 port->ops->poll_put_char(port, ch);
2270}
2271#endif
2272
2273static const struct tty_operations uart_ops = {
2274 .open = uart_open,
2275 .close = uart_close,
2276 .write = uart_write,
2277 .put_char = uart_put_char,
2278 .flush_chars = uart_flush_chars,
2279 .write_room = uart_write_room,
2280 .chars_in_buffer= uart_chars_in_buffer,
2281 .flush_buffer = uart_flush_buffer,
2282 .ioctl = uart_ioctl,
2283 .throttle = uart_throttle,
2284 .unthrottle = uart_unthrottle,
2285 .send_xchar = uart_send_xchar,
2286 .set_termios = uart_set_termios,
2287 .set_ldisc = uart_set_ldisc,
2288 .stop = uart_stop,
2289 .start = uart_start,
2290 .hangup = uart_hangup,
2291 .break_ctl = uart_break_ctl,
2292 .wait_until_sent= uart_wait_until_sent,
2293#ifdef CONFIG_PROC_FS
2294 .proc_fops = &uart_proc_fops,
2295#endif
2296 .tiocmget = uart_tiocmget,
2297 .tiocmset = uart_tiocmset,
2298 .get_icount = uart_get_icount,
2299#ifdef CONFIG_CONSOLE_POLL
2300 .poll_init = uart_poll_init,
2301 .poll_get_char = uart_poll_get_char,
2302 .poll_put_char = uart_poll_put_char,
2303#endif
2304};
2305
2306static const struct tty_port_operations uart_port_ops = {
2307 .carrier_raised = uart_carrier_raised,
2308 .dtr_rts = uart_dtr_rts,
2309};
2310
2311/**
2312 * uart_register_driver - register a driver with the uart core layer
2313 * @drv: low level driver structure
2314 *
2315 * Register a uart driver with the core driver. We in turn register
2316 * with the tty layer, and initialise the core driver per-port state.
2317 *
2318 * We have a proc file in /proc/tty/driver which is named after the
2319 * normal driver.
2320 *
2321 * drv->port should be NULL, and the per-port structures should be
2322 * registered using uart_add_one_port after this call has succeeded.
2323 */
2324int uart_register_driver(struct uart_driver *drv)
2325{
2326 struct tty_driver *normal;
2327 int i, retval;
2328
2329 BUG_ON(drv->state);
2330
2331 /*
2332 * Maybe we should be using a slab cache for this, especially if
2333 * we have a large number of ports to handle.
2334 */
2335 drv->state = kzalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL);
2336 if (!drv->state)
2337 goto out;
2338
2339 normal = alloc_tty_driver(drv->nr);
2340 if (!normal)
2341 goto out_kfree;
2342
2343 drv->tty_driver = normal;
2344
2345 normal->owner = drv->owner;
2346 normal->driver_name = drv->driver_name;
2347 normal->name = drv->dev_name;
2348 normal->major = drv->major;
2349 normal->minor_start = drv->minor;
2350 normal->type = TTY_DRIVER_TYPE_SERIAL;
2351 normal->subtype = SERIAL_TYPE_NORMAL;
2352 normal->init_termios = tty_std_termios;
2353 normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
2354 normal->init_termios.c_ispeed = normal->init_termios.c_ospeed = 9600;
2355 normal->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
2356 normal->driver_state = drv;
2357 tty_set_operations(normal, &uart_ops);
2358
2359 /*
2360 * Initialise the UART state(s).
2361 */
2362 for (i = 0; i < drv->nr; i++) {
2363 struct uart_state *state = drv->state + i;
2364 struct tty_port *port = &state->port;
2365
2366 tty_port_init(port);
2367 port->ops = &uart_port_ops;
2368 port->close_delay = 500; /* .5 seconds */
2369 port->closing_wait = 30000; /* 30 seconds */
2370 tasklet_init(&state->tlet, uart_tasklet_action,
2371 (unsigned long)state);
2372 }
2373
2374 retval = tty_register_driver(normal);
2375 if (retval >= 0)
2376 return retval;
2377
2378 put_tty_driver(normal);
2379out_kfree:
2380 kfree(drv->state);
2381out:
2382 return -ENOMEM;
2383}
2384
2385/**
2386 * uart_unregister_driver - remove a driver from the uart core layer
2387 * @drv: low level driver structure
2388 *
2389 * Remove all references to a driver from the core driver. The low
2390 * level driver must have removed all its ports via the
2391 * uart_remove_one_port() if it registered them with uart_add_one_port().
2392 * (ie, drv->port == NULL)
2393 */
2394void uart_unregister_driver(struct uart_driver *drv)
2395{
2396 struct tty_driver *p = drv->tty_driver;
2397 tty_unregister_driver(p);
2398 put_tty_driver(p);
2399 kfree(drv->state);
2400 drv->tty_driver = NULL;
2401}
2402
2403struct tty_driver *uart_console_device(struct console *co, int *index)
2404{
2405 struct uart_driver *p = co->data;
2406 *index = co->index;
2407 return p->tty_driver;
2408}
2409
2410/**
2411 * uart_add_one_port - attach a driver-defined port structure
2412 * @drv: pointer to the uart low level driver structure for this port
2413 * @uport: uart port structure to use for this port.
2414 *
2415 * This allows the driver to register its own uart_port structure
2416 * with the core driver. The main purpose is to allow the low
2417 * level uart drivers to expand uart_port, rather than having yet
2418 * more levels of structures.
2419 */
2420int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
2421{
2422 struct uart_state *state;
2423 struct tty_port *port;
2424 int ret = 0;
2425 struct device *tty_dev;
2426
2427 BUG_ON(in_interrupt());
2428
2429 if (uport->line >= drv->nr)
2430 return -EINVAL;
2431
2432 state = drv->state + uport->line;
2433 port = &state->port;
2434
2435 mutex_lock(&port_mutex);
2436 mutex_lock(&port->mutex);
2437 if (state->uart_port) {
2438 ret = -EINVAL;
2439 goto out;
2440 }
2441
2442 state->uart_port = uport;
2443 state->pm_state = -1;
2444
2445 uport->cons = drv->cons;
2446 uport->state = state;
2447
2448 /*
2449 * If this port is a console, then the spinlock is already
2450 * initialised.
2451 */
2452 if (!(uart_console(uport) && (uport->cons->flags & CON_ENABLED))) {
2453 spin_lock_init(&uport->lock);
2454 lockdep_set_class(&uport->lock, &port_lock_key);
2455 }
2456
2457 uart_configure_port(drv, state, uport);
2458
2459 /*
2460 * Register the port whether it's detected or not. This allows
2461 * setserial to be used to alter this ports parameters.
2462 */
2463 tty_dev = tty_register_device(drv->tty_driver, uport->line, uport->dev);
2464 if (likely(!IS_ERR(tty_dev))) {
2465 device_init_wakeup(tty_dev, 1);
2466 device_set_wakeup_enable(tty_dev, 0);
2467 } else
2468 printk(KERN_ERR "Cannot register tty device on line %d\n",
2469 uport->line);
2470
2471 /*
2472 * Ensure UPF_DEAD is not set.
2473 */
2474 uport->flags &= ~UPF_DEAD;
2475
2476 out:
2477 mutex_unlock(&port->mutex);
2478 mutex_unlock(&port_mutex);
2479
2480 return ret;
2481}
2482
2483/**
2484 * uart_remove_one_port - detach a driver defined port structure
2485 * @drv: pointer to the uart low level driver structure for this port
2486 * @uport: uart port structure for this port
2487 *
2488 * This unhooks (and hangs up) the specified port structure from the
2489 * core driver. No further calls will be made to the low-level code
2490 * for this port.
2491 */
2492int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
2493{
2494 struct uart_state *state = drv->state + uport->line;
2495 struct tty_port *port = &state->port;
2496
2497 BUG_ON(in_interrupt());
2498
2499 if (state->uart_port != uport)
2500 printk(KERN_ALERT "Removing wrong port: %p != %p\n",
2501 state->uart_port, uport);
2502
2503 mutex_lock(&port_mutex);
2504
2505 /*
2506 * Mark the port "dead" - this prevents any opens from
2507 * succeeding while we shut down the port.
2508 */
2509 mutex_lock(&port->mutex);
2510 uport->flags |= UPF_DEAD;
2511 mutex_unlock(&port->mutex);
2512
2513 /*
2514 * Remove the devices from the tty layer
2515 */
2516 tty_unregister_device(drv->tty_driver, uport->line);
2517
2518 if (port->tty)
2519 tty_vhangup(port->tty);
2520
2521 /*
2522 * Free the port IO and memory resources, if any.
2523 */
2524 if (uport->type != PORT_UNKNOWN)
2525 uport->ops->release_port(uport);
2526
2527 /*
2528 * Indicate that there isn't a port here anymore.
2529 */
2530 uport->type = PORT_UNKNOWN;
2531
2532 /*
2533 * Kill the tasklet, and free resources.
2534 */
2535 tasklet_kill(&state->tlet);
2536
2537 state->uart_port = NULL;
2538 mutex_unlock(&port_mutex);
2539
2540 return 0;
2541}
2542
2543/*
2544 * Are the two ports equivalent?
2545 */
2546int uart_match_port(struct uart_port *port1, struct uart_port *port2)
2547{
2548 if (port1->iotype != port2->iotype)
2549 return 0;
2550
2551 switch (port1->iotype) {
2552 case UPIO_PORT:
2553 return (port1->iobase == port2->iobase);
2554 case UPIO_HUB6:
2555 return (port1->iobase == port2->iobase) &&
2556 (port1->hub6 == port2->hub6);
2557 case UPIO_MEM:
2558 case UPIO_MEM32:
2559 case UPIO_AU:
2560 case UPIO_TSI:
2561 case UPIO_DWAPB:
2562 case UPIO_DWAPB32:
2563 return (port1->mapbase == port2->mapbase);
2564 }
2565 return 0;
2566}
2567EXPORT_SYMBOL(uart_match_port);
2568
2569EXPORT_SYMBOL(uart_write_wakeup);
2570EXPORT_SYMBOL(uart_register_driver);
2571EXPORT_SYMBOL(uart_unregister_driver);
2572EXPORT_SYMBOL(uart_suspend_port);
2573EXPORT_SYMBOL(uart_resume_port);
2574EXPORT_SYMBOL(uart_add_one_port);
2575EXPORT_SYMBOL(uart_remove_one_port);
2576
2577MODULE_DESCRIPTION("Serial driver core");
2578MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-04 19:06:24 -0500