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1da177e4 LT |
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/config.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/tty.h> | |
28 | #include <linux/slab.h> | |
29 | #include <linux/init.h> | |
30 | #include <linux/console.h> | |
31 | #include <linux/serial_core.h> | |
32 | #include <linux/smp_lock.h> | |
33 | #include <linux/device.h> | |
34 | #include <linux/serial.h> /* for serial_state and serial_icounter_struct */ | |
35 | #include <linux/delay.h> | |
36 | ||
37 | #include <asm/irq.h> | |
38 | #include <asm/uaccess.h> | |
39 | ||
40 | #undef DEBUG | |
41 | #ifdef DEBUG | |
42 | #define DPRINTK(x...) printk(x) | |
43 | #else | |
44 | #define DPRINTK(x...) do { } while (0) | |
45 | #endif | |
46 | ||
47 | /* | |
48 | * This is used to lock changes in serial line configuration. | |
49 | */ | |
50 | static DECLARE_MUTEX(port_sem); | |
51 | ||
52 | #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8) | |
53 | ||
54 | #define uart_users(state) ((state)->count + ((state)->info ? (state)->info->blocked_open : 0)) | |
55 | ||
56 | #ifdef CONFIG_SERIAL_CORE_CONSOLE | |
57 | #define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line) | |
58 | #else | |
59 | #define uart_console(port) (0) | |
60 | #endif | |
61 | ||
62 | static void uart_change_speed(struct uart_state *state, struct termios *old_termios); | |
63 | static void uart_wait_until_sent(struct tty_struct *tty, int timeout); | |
64 | static 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 | */ | |
70 | void uart_write_wakeup(struct uart_port *port) | |
71 | { | |
72 | struct uart_info *info = port->info; | |
73 | tasklet_schedule(&info->tlet); | |
74 | } | |
75 | ||
76 | static void uart_stop(struct tty_struct *tty) | |
77 | { | |
78 | struct uart_state *state = tty->driver_data; | |
79 | struct uart_port *port = state->port; | |
80 | unsigned long flags; | |
81 | ||
82 | spin_lock_irqsave(&port->lock, flags); | |
83 | port->ops->stop_tx(port, 1); | |
84 | spin_unlock_irqrestore(&port->lock, flags); | |
85 | } | |
86 | ||
87 | static void __uart_start(struct tty_struct *tty) | |
88 | { | |
89 | struct uart_state *state = tty->driver_data; | |
90 | struct uart_port *port = state->port; | |
91 | ||
92 | if (!uart_circ_empty(&state->info->xmit) && state->info->xmit.buf && | |
93 | !tty->stopped && !tty->hw_stopped) | |
94 | port->ops->start_tx(port, 1); | |
95 | } | |
96 | ||
97 | static void uart_start(struct tty_struct *tty) | |
98 | { | |
99 | struct uart_state *state = tty->driver_data; | |
100 | struct uart_port *port = state->port; | |
101 | unsigned long flags; | |
102 | ||
103 | spin_lock_irqsave(&port->lock, flags); | |
104 | __uart_start(tty); | |
105 | spin_unlock_irqrestore(&port->lock, flags); | |
106 | } | |
107 | ||
108 | static void uart_tasklet_action(unsigned long data) | |
109 | { | |
110 | struct uart_state *state = (struct uart_state *)data; | |
111 | tty_wakeup(state->info->tty); | |
112 | } | |
113 | ||
114 | static inline void | |
115 | uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear) | |
116 | { | |
117 | unsigned long flags; | |
118 | unsigned int old; | |
119 | ||
120 | spin_lock_irqsave(&port->lock, flags); | |
121 | old = port->mctrl; | |
122 | port->mctrl = (old & ~clear) | set; | |
123 | if (old != port->mctrl) | |
124 | port->ops->set_mctrl(port, port->mctrl); | |
125 | spin_unlock_irqrestore(&port->lock, flags); | |
126 | } | |
127 | ||
128 | #define uart_set_mctrl(port,set) uart_update_mctrl(port,set,0) | |
129 | #define uart_clear_mctrl(port,clear) uart_update_mctrl(port,0,clear) | |
130 | ||
131 | /* | |
132 | * Startup the port. This will be called once per open. All calls | |
133 | * will be serialised by the per-port semaphore. | |
134 | */ | |
135 | static int uart_startup(struct uart_state *state, int init_hw) | |
136 | { | |
137 | struct uart_info *info = state->info; | |
138 | struct uart_port *port = state->port; | |
139 | unsigned long page; | |
140 | int retval = 0; | |
141 | ||
142 | if (info->flags & UIF_INITIALIZED) | |
143 | return 0; | |
144 | ||
145 | /* | |
146 | * Set the TTY IO error marker - we will only clear this | |
147 | * once we have successfully opened the port. Also set | |
148 | * up the tty->alt_speed kludge | |
149 | */ | |
150 | if (info->tty) | |
151 | set_bit(TTY_IO_ERROR, &info->tty->flags); | |
152 | ||
153 | if (port->type == PORT_UNKNOWN) | |
154 | return 0; | |
155 | ||
156 | /* | |
157 | * Initialise and allocate the transmit and temporary | |
158 | * buffer. | |
159 | */ | |
160 | if (!info->xmit.buf) { | |
161 | page = get_zeroed_page(GFP_KERNEL); | |
162 | if (!page) | |
163 | return -ENOMEM; | |
164 | ||
165 | info->xmit.buf = (unsigned char *) page; | |
166 | uart_circ_clear(&info->xmit); | |
167 | } | |
168 | ||
169 | retval = port->ops->startup(port); | |
170 | if (retval == 0) { | |
171 | if (init_hw) { | |
172 | /* | |
173 | * Initialise the hardware port settings. | |
174 | */ | |
175 | uart_change_speed(state, NULL); | |
176 | ||
177 | /* | |
178 | * Setup the RTS and DTR signals once the | |
179 | * port is open and ready to respond. | |
180 | */ | |
181 | if (info->tty->termios->c_cflag & CBAUD) | |
182 | uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR); | |
183 | } | |
184 | ||
0dd7a1ae RK |
185 | if (info->flags & UIF_CTS_FLOW) { |
186 | spin_lock_irq(&port->lock); | |
187 | if (!(port->ops->get_mctrl(port) & TIOCM_CTS)) | |
188 | info->tty->hw_stopped = 1; | |
189 | spin_unlock_irq(&port->lock); | |
190 | } | |
191 | ||
1da177e4 LT |
192 | info->flags |= UIF_INITIALIZED; |
193 | ||
194 | clear_bit(TTY_IO_ERROR, &info->tty->flags); | |
195 | } | |
196 | ||
197 | if (retval && capable(CAP_SYS_ADMIN)) | |
198 | retval = 0; | |
199 | ||
200 | return retval; | |
201 | } | |
202 | ||
203 | /* | |
204 | * This routine will shutdown a serial port; interrupts are disabled, and | |
205 | * DTR is dropped if the hangup on close termio flag is on. Calls to | |
206 | * uart_shutdown are serialised by the per-port semaphore. | |
207 | */ | |
208 | static void uart_shutdown(struct uart_state *state) | |
209 | { | |
210 | struct uart_info *info = state->info; | |
211 | struct uart_port *port = state->port; | |
212 | ||
213 | if (!(info->flags & UIF_INITIALIZED)) | |
214 | return; | |
215 | ||
216 | /* | |
217 | * Turn off DTR and RTS early. | |
218 | */ | |
219 | if (!info->tty || (info->tty->termios->c_cflag & HUPCL)) | |
220 | uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); | |
221 | ||
222 | /* | |
223 | * clear delta_msr_wait queue to avoid mem leaks: we may free | |
224 | * the irq here so the queue might never be woken up. Note | |
225 | * that we won't end up waiting on delta_msr_wait again since | |
226 | * any outstanding file descriptors should be pointing at | |
227 | * hung_up_tty_fops now. | |
228 | */ | |
229 | wake_up_interruptible(&info->delta_msr_wait); | |
230 | ||
231 | /* | |
232 | * Free the IRQ and disable the port. | |
233 | */ | |
234 | port->ops->shutdown(port); | |
235 | ||
236 | /* | |
237 | * Ensure that the IRQ handler isn't running on another CPU. | |
238 | */ | |
239 | synchronize_irq(port->irq); | |
240 | ||
241 | /* | |
242 | * Free the transmit buffer page. | |
243 | */ | |
244 | if (info->xmit.buf) { | |
245 | free_page((unsigned long)info->xmit.buf); | |
246 | info->xmit.buf = NULL; | |
247 | } | |
248 | ||
249 | /* | |
250 | * kill off our tasklet | |
251 | */ | |
252 | tasklet_kill(&info->tlet); | |
253 | if (info->tty) | |
254 | set_bit(TTY_IO_ERROR, &info->tty->flags); | |
255 | ||
256 | info->flags &= ~UIF_INITIALIZED; | |
257 | } | |
258 | ||
259 | /** | |
260 | * uart_update_timeout - update per-port FIFO timeout. | |
261 | * @port: uart_port structure describing the port | |
262 | * @cflag: termios cflag value | |
263 | * @baud: speed of the port | |
264 | * | |
265 | * Set the port FIFO timeout value. The @cflag value should | |
266 | * reflect the actual hardware settings. | |
267 | */ | |
268 | void | |
269 | uart_update_timeout(struct uart_port *port, unsigned int cflag, | |
270 | unsigned int baud) | |
271 | { | |
272 | unsigned int bits; | |
273 | ||
274 | /* byte size and parity */ | |
275 | switch (cflag & CSIZE) { | |
276 | case CS5: | |
277 | bits = 7; | |
278 | break; | |
279 | case CS6: | |
280 | bits = 8; | |
281 | break; | |
282 | case CS7: | |
283 | bits = 9; | |
284 | break; | |
285 | default: | |
286 | bits = 10; | |
287 | break; // CS8 | |
288 | } | |
289 | ||
290 | if (cflag & CSTOPB) | |
291 | bits++; | |
292 | if (cflag & PARENB) | |
293 | bits++; | |
294 | ||
295 | /* | |
296 | * The total number of bits to be transmitted in the fifo. | |
297 | */ | |
298 | bits = bits * port->fifosize; | |
299 | ||
300 | /* | |
301 | * Figure the timeout to send the above number of bits. | |
302 | * Add .02 seconds of slop | |
303 | */ | |
304 | port->timeout = (HZ * bits) / baud + HZ/50; | |
305 | } | |
306 | ||
307 | EXPORT_SYMBOL(uart_update_timeout); | |
308 | ||
309 | /** | |
310 | * uart_get_baud_rate - return baud rate for a particular port | |
311 | * @port: uart_port structure describing the port in question. | |
312 | * @termios: desired termios settings. | |
313 | * @old: old termios (or NULL) | |
314 | * @min: minimum acceptable baud rate | |
315 | * @max: maximum acceptable baud rate | |
316 | * | |
317 | * Decode the termios structure into a numeric baud rate, | |
318 | * taking account of the magic 38400 baud rate (with spd_* | |
319 | * flags), and mapping the %B0 rate to 9600 baud. | |
320 | * | |
321 | * If the new baud rate is invalid, try the old termios setting. | |
322 | * If it's still invalid, we try 9600 baud. | |
323 | * | |
324 | * Update the @termios structure to reflect the baud rate | |
325 | * we're actually going to be using. | |
326 | */ | |
327 | unsigned int | |
328 | uart_get_baud_rate(struct uart_port *port, struct termios *termios, | |
329 | struct termios *old, unsigned int min, unsigned int max) | |
330 | { | |
331 | unsigned int try, baud, altbaud = 38400; | |
332 | unsigned int flags = port->flags & UPF_SPD_MASK; | |
333 | ||
334 | if (flags == UPF_SPD_HI) | |
335 | altbaud = 57600; | |
336 | if (flags == UPF_SPD_VHI) | |
337 | altbaud = 115200; | |
338 | if (flags == UPF_SPD_SHI) | |
339 | altbaud = 230400; | |
340 | if (flags == UPF_SPD_WARP) | |
341 | altbaud = 460800; | |
342 | ||
343 | for (try = 0; try < 2; try++) { | |
344 | baud = tty_termios_baud_rate(termios); | |
345 | ||
346 | /* | |
347 | * The spd_hi, spd_vhi, spd_shi, spd_warp kludge... | |
348 | * Die! Die! Die! | |
349 | */ | |
350 | if (baud == 38400) | |
351 | baud = altbaud; | |
352 | ||
353 | /* | |
354 | * Special case: B0 rate. | |
355 | */ | |
356 | if (baud == 0) | |
357 | baud = 9600; | |
358 | ||
359 | if (baud >= min && baud <= max) | |
360 | return baud; | |
361 | ||
362 | /* | |
363 | * Oops, the quotient was zero. Try again with | |
364 | * the old baud rate if possible. | |
365 | */ | |
366 | termios->c_cflag &= ~CBAUD; | |
367 | if (old) { | |
368 | termios->c_cflag |= old->c_cflag & CBAUD; | |
369 | old = NULL; | |
370 | continue; | |
371 | } | |
372 | ||
373 | /* | |
374 | * As a last resort, if the quotient is zero, | |
375 | * default to 9600 bps | |
376 | */ | |
377 | termios->c_cflag |= B9600; | |
378 | } | |
379 | ||
380 | return 0; | |
381 | } | |
382 | ||
383 | EXPORT_SYMBOL(uart_get_baud_rate); | |
384 | ||
385 | /** | |
386 | * uart_get_divisor - return uart clock divisor | |
387 | * @port: uart_port structure describing the port. | |
388 | * @baud: desired baud rate | |
389 | * | |
390 | * Calculate the uart clock divisor for the port. | |
391 | */ | |
392 | unsigned int | |
393 | uart_get_divisor(struct uart_port *port, unsigned int baud) | |
394 | { | |
395 | unsigned int quot; | |
396 | ||
397 | /* | |
398 | * Old custom speed handling. | |
399 | */ | |
400 | if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) | |
401 | quot = port->custom_divisor; | |
402 | else | |
403 | quot = (port->uartclk + (8 * baud)) / (16 * baud); | |
404 | ||
405 | return quot; | |
406 | } | |
407 | ||
408 | EXPORT_SYMBOL(uart_get_divisor); | |
409 | ||
410 | static void | |
411 | uart_change_speed(struct uart_state *state, struct termios *old_termios) | |
412 | { | |
413 | struct tty_struct *tty = state->info->tty; | |
414 | struct uart_port *port = state->port; | |
415 | struct termios *termios; | |
416 | ||
417 | /* | |
418 | * If we have no tty, termios, or the port does not exist, | |
419 | * then we can't set the parameters for this port. | |
420 | */ | |
421 | if (!tty || !tty->termios || port->type == PORT_UNKNOWN) | |
422 | return; | |
423 | ||
424 | termios = tty->termios; | |
425 | ||
426 | /* | |
427 | * Set flags based on termios cflag | |
428 | */ | |
429 | if (termios->c_cflag & CRTSCTS) | |
430 | state->info->flags |= UIF_CTS_FLOW; | |
431 | else | |
432 | state->info->flags &= ~UIF_CTS_FLOW; | |
433 | ||
434 | if (termios->c_cflag & CLOCAL) | |
435 | state->info->flags &= ~UIF_CHECK_CD; | |
436 | else | |
437 | state->info->flags |= UIF_CHECK_CD; | |
438 | ||
439 | port->ops->set_termios(port, termios, old_termios); | |
440 | } | |
441 | ||
442 | static inline void | |
443 | __uart_put_char(struct uart_port *port, struct circ_buf *circ, unsigned char c) | |
444 | { | |
445 | unsigned long flags; | |
446 | ||
447 | if (!circ->buf) | |
448 | return; | |
449 | ||
450 | spin_lock_irqsave(&port->lock, flags); | |
451 | if (uart_circ_chars_free(circ) != 0) { | |
452 | circ->buf[circ->head] = c; | |
453 | circ->head = (circ->head + 1) & (UART_XMIT_SIZE - 1); | |
454 | } | |
455 | spin_unlock_irqrestore(&port->lock, flags); | |
456 | } | |
457 | ||
458 | static void uart_put_char(struct tty_struct *tty, unsigned char ch) | |
459 | { | |
460 | struct uart_state *state = tty->driver_data; | |
461 | ||
462 | __uart_put_char(state->port, &state->info->xmit, ch); | |
463 | } | |
464 | ||
465 | static void uart_flush_chars(struct tty_struct *tty) | |
466 | { | |
467 | uart_start(tty); | |
468 | } | |
469 | ||
470 | static int | |
471 | uart_write(struct tty_struct *tty, const unsigned char * buf, int count) | |
472 | { | |
473 | struct uart_state *state = tty->driver_data; | |
474 | struct uart_port *port = state->port; | |
475 | struct circ_buf *circ = &state->info->xmit; | |
476 | unsigned long flags; | |
477 | int c, ret = 0; | |
478 | ||
479 | if (!circ->buf) | |
480 | return 0; | |
481 | ||
482 | spin_lock_irqsave(&port->lock, flags); | |
483 | while (1) { | |
484 | c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE); | |
485 | if (count < c) | |
486 | c = count; | |
487 | if (c <= 0) | |
488 | break; | |
489 | memcpy(circ->buf + circ->head, buf, c); | |
490 | circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1); | |
491 | buf += c; | |
492 | count -= c; | |
493 | ret += c; | |
494 | } | |
495 | spin_unlock_irqrestore(&port->lock, flags); | |
496 | ||
497 | uart_start(tty); | |
498 | return ret; | |
499 | } | |
500 | ||
501 | static int uart_write_room(struct tty_struct *tty) | |
502 | { | |
503 | struct uart_state *state = tty->driver_data; | |
504 | ||
505 | return uart_circ_chars_free(&state->info->xmit); | |
506 | } | |
507 | ||
508 | static int uart_chars_in_buffer(struct tty_struct *tty) | |
509 | { | |
510 | struct uart_state *state = tty->driver_data; | |
511 | ||
512 | return uart_circ_chars_pending(&state->info->xmit); | |
513 | } | |
514 | ||
515 | static void uart_flush_buffer(struct tty_struct *tty) | |
516 | { | |
517 | struct uart_state *state = tty->driver_data; | |
518 | struct uart_port *port = state->port; | |
519 | unsigned long flags; | |
520 | ||
521 | DPRINTK("uart_flush_buffer(%d) called\n", tty->index); | |
522 | ||
523 | spin_lock_irqsave(&port->lock, flags); | |
524 | uart_circ_clear(&state->info->xmit); | |
525 | spin_unlock_irqrestore(&port->lock, flags); | |
526 | tty_wakeup(tty); | |
527 | } | |
528 | ||
529 | /* | |
530 | * This function is used to send a high-priority XON/XOFF character to | |
531 | * the device | |
532 | */ | |
533 | static void uart_send_xchar(struct tty_struct *tty, char ch) | |
534 | { | |
535 | struct uart_state *state = tty->driver_data; | |
536 | struct uart_port *port = state->port; | |
537 | unsigned long flags; | |
538 | ||
539 | if (port->ops->send_xchar) | |
540 | port->ops->send_xchar(port, ch); | |
541 | else { | |
542 | port->x_char = ch; | |
543 | if (ch) { | |
544 | spin_lock_irqsave(&port->lock, flags); | |
545 | port->ops->start_tx(port, 0); | |
546 | spin_unlock_irqrestore(&port->lock, flags); | |
547 | } | |
548 | } | |
549 | } | |
550 | ||
551 | static void uart_throttle(struct tty_struct *tty) | |
552 | { | |
553 | struct uart_state *state = tty->driver_data; | |
554 | ||
555 | if (I_IXOFF(tty)) | |
556 | uart_send_xchar(tty, STOP_CHAR(tty)); | |
557 | ||
558 | if (tty->termios->c_cflag & CRTSCTS) | |
559 | uart_clear_mctrl(state->port, TIOCM_RTS); | |
560 | } | |
561 | ||
562 | static void uart_unthrottle(struct tty_struct *tty) | |
563 | { | |
564 | struct uart_state *state = tty->driver_data; | |
565 | struct uart_port *port = state->port; | |
566 | ||
567 | if (I_IXOFF(tty)) { | |
568 | if (port->x_char) | |
569 | port->x_char = 0; | |
570 | else | |
571 | uart_send_xchar(tty, START_CHAR(tty)); | |
572 | } | |
573 | ||
574 | if (tty->termios->c_cflag & CRTSCTS) | |
575 | uart_set_mctrl(port, TIOCM_RTS); | |
576 | } | |
577 | ||
578 | static int uart_get_info(struct uart_state *state, | |
579 | struct serial_struct __user *retinfo) | |
580 | { | |
581 | struct uart_port *port = state->port; | |
582 | struct serial_struct tmp; | |
583 | ||
584 | memset(&tmp, 0, sizeof(tmp)); | |
585 | tmp.type = port->type; | |
586 | tmp.line = port->line; | |
587 | tmp.port = port->iobase; | |
588 | if (HIGH_BITS_OFFSET) | |
589 | tmp.port_high = (long) port->iobase >> HIGH_BITS_OFFSET; | |
590 | tmp.irq = port->irq; | |
591 | tmp.flags = port->flags; | |
592 | tmp.xmit_fifo_size = port->fifosize; | |
593 | tmp.baud_base = port->uartclk / 16; | |
594 | tmp.close_delay = state->close_delay / 10; | |
595 | tmp.closing_wait = state->closing_wait == USF_CLOSING_WAIT_NONE ? | |
596 | ASYNC_CLOSING_WAIT_NONE : | |
597 | state->closing_wait / 10; | |
598 | tmp.custom_divisor = port->custom_divisor; | |
599 | tmp.hub6 = port->hub6; | |
600 | tmp.io_type = port->iotype; | |
601 | tmp.iomem_reg_shift = port->regshift; | |
602 | tmp.iomem_base = (void *)port->mapbase; | |
603 | ||
604 | if (copy_to_user(retinfo, &tmp, sizeof(*retinfo))) | |
605 | return -EFAULT; | |
606 | return 0; | |
607 | } | |
608 | ||
609 | static int uart_set_info(struct uart_state *state, | |
610 | struct serial_struct __user *newinfo) | |
611 | { | |
612 | struct serial_struct new_serial; | |
613 | struct uart_port *port = state->port; | |
614 | unsigned long new_port; | |
615 | unsigned int change_irq, change_port, old_flags, closing_wait; | |
616 | unsigned int old_custom_divisor, close_delay; | |
617 | int retval = 0; | |
618 | ||
619 | if (copy_from_user(&new_serial, newinfo, sizeof(new_serial))) | |
620 | return -EFAULT; | |
621 | ||
622 | new_port = new_serial.port; | |
623 | if (HIGH_BITS_OFFSET) | |
624 | new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET; | |
625 | ||
626 | new_serial.irq = irq_canonicalize(new_serial.irq); | |
627 | close_delay = new_serial.close_delay * 10; | |
628 | closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ? | |
629 | USF_CLOSING_WAIT_NONE : new_serial.closing_wait * 10; | |
630 | ||
631 | /* | |
632 | * This semaphore protects state->count. It is also | |
633 | * very useful to prevent opens. Also, take the | |
634 | * port configuration semaphore to make sure that a | |
635 | * module insertion/removal doesn't change anything | |
636 | * under us. | |
637 | */ | |
638 | down(&state->sem); | |
639 | ||
640 | change_irq = new_serial.irq != port->irq; | |
641 | ||
642 | /* | |
643 | * Since changing the 'type' of the port changes its resource | |
644 | * allocations, we should treat type changes the same as | |
645 | * IO port changes. | |
646 | */ | |
647 | change_port = new_port != port->iobase || | |
648 | (unsigned long)new_serial.iomem_base != port->mapbase || | |
649 | new_serial.hub6 != port->hub6 || | |
650 | new_serial.io_type != port->iotype || | |
651 | new_serial.iomem_reg_shift != port->regshift || | |
652 | new_serial.type != port->type; | |
653 | ||
654 | old_flags = port->flags; | |
655 | old_custom_divisor = port->custom_divisor; | |
656 | ||
657 | if (!capable(CAP_SYS_ADMIN)) { | |
658 | retval = -EPERM; | |
659 | if (change_irq || change_port || | |
660 | (new_serial.baud_base != port->uartclk / 16) || | |
661 | (close_delay != state->close_delay) || | |
662 | (closing_wait != state->closing_wait) || | |
663 | (new_serial.xmit_fifo_size != port->fifosize) || | |
664 | (((new_serial.flags ^ old_flags) & ~UPF_USR_MASK) != 0)) | |
665 | goto exit; | |
666 | port->flags = ((port->flags & ~UPF_USR_MASK) | | |
667 | (new_serial.flags & UPF_USR_MASK)); | |
668 | port->custom_divisor = new_serial.custom_divisor; | |
669 | goto check_and_exit; | |
670 | } | |
671 | ||
672 | /* | |
673 | * Ask the low level driver to verify the settings. | |
674 | */ | |
675 | if (port->ops->verify_port) | |
676 | retval = port->ops->verify_port(port, &new_serial); | |
677 | ||
678 | if ((new_serial.irq >= NR_IRQS) || (new_serial.irq < 0) || | |
679 | (new_serial.baud_base < 9600)) | |
680 | retval = -EINVAL; | |
681 | ||
682 | if (retval) | |
683 | goto exit; | |
684 | ||
685 | if (change_port || change_irq) { | |
686 | retval = -EBUSY; | |
687 | ||
688 | /* | |
689 | * Make sure that we are the sole user of this port. | |
690 | */ | |
691 | if (uart_users(state) > 1) | |
692 | goto exit; | |
693 | ||
694 | /* | |
695 | * We need to shutdown the serial port at the old | |
696 | * port/type/irq combination. | |
697 | */ | |
698 | uart_shutdown(state); | |
699 | } | |
700 | ||
701 | if (change_port) { | |
702 | unsigned long old_iobase, old_mapbase; | |
703 | unsigned int old_type, old_iotype, old_hub6, old_shift; | |
704 | ||
705 | old_iobase = port->iobase; | |
706 | old_mapbase = port->mapbase; | |
707 | old_type = port->type; | |
708 | old_hub6 = port->hub6; | |
709 | old_iotype = port->iotype; | |
710 | old_shift = port->regshift; | |
711 | ||
712 | /* | |
713 | * Free and release old regions | |
714 | */ | |
715 | if (old_type != PORT_UNKNOWN) | |
716 | port->ops->release_port(port); | |
717 | ||
718 | port->iobase = new_port; | |
719 | port->type = new_serial.type; | |
720 | port->hub6 = new_serial.hub6; | |
721 | port->iotype = new_serial.io_type; | |
722 | port->regshift = new_serial.iomem_reg_shift; | |
723 | port->mapbase = (unsigned long)new_serial.iomem_base; | |
724 | ||
725 | /* | |
726 | * Claim and map the new regions | |
727 | */ | |
728 | if (port->type != PORT_UNKNOWN) { | |
729 | retval = port->ops->request_port(port); | |
730 | } else { | |
731 | /* Always success - Jean II */ | |
732 | retval = 0; | |
733 | } | |
734 | ||
735 | /* | |
736 | * If we fail to request resources for the | |
737 | * new port, try to restore the old settings. | |
738 | */ | |
739 | if (retval && old_type != PORT_UNKNOWN) { | |
740 | port->iobase = old_iobase; | |
741 | port->type = old_type; | |
742 | port->hub6 = old_hub6; | |
743 | port->iotype = old_iotype; | |
744 | port->regshift = old_shift; | |
745 | port->mapbase = old_mapbase; | |
746 | retval = port->ops->request_port(port); | |
747 | /* | |
748 | * If we failed to restore the old settings, | |
749 | * we fail like this. | |
750 | */ | |
751 | if (retval) | |
752 | port->type = PORT_UNKNOWN; | |
753 | ||
754 | /* | |
755 | * We failed anyway. | |
756 | */ | |
757 | retval = -EBUSY; | |
758 | } | |
759 | } | |
760 | ||
761 | port->irq = new_serial.irq; | |
762 | port->uartclk = new_serial.baud_base * 16; | |
763 | port->flags = (port->flags & ~UPF_CHANGE_MASK) | | |
764 | (new_serial.flags & UPF_CHANGE_MASK); | |
765 | port->custom_divisor = new_serial.custom_divisor; | |
766 | state->close_delay = close_delay; | |
767 | state->closing_wait = closing_wait; | |
768 | port->fifosize = new_serial.xmit_fifo_size; | |
769 | if (state->info->tty) | |
770 | state->info->tty->low_latency = | |
771 | (port->flags & UPF_LOW_LATENCY) ? 1 : 0; | |
772 | ||
773 | check_and_exit: | |
774 | retval = 0; | |
775 | if (port->type == PORT_UNKNOWN) | |
776 | goto exit; | |
777 | if (state->info->flags & UIF_INITIALIZED) { | |
778 | if (((old_flags ^ port->flags) & UPF_SPD_MASK) || | |
779 | old_custom_divisor != port->custom_divisor) { | |
780 | /* | |
781 | * If they're setting up a custom divisor or speed, | |
782 | * instead of clearing it, then bitch about it. No | |
783 | * need to rate-limit; it's CAP_SYS_ADMIN only. | |
784 | */ | |
785 | if (port->flags & UPF_SPD_MASK) { | |
786 | char buf[64]; | |
787 | printk(KERN_NOTICE | |
788 | "%s sets custom speed on %s. This " | |
789 | "is deprecated.\n", current->comm, | |
790 | tty_name(state->info->tty, buf)); | |
791 | } | |
792 | uart_change_speed(state, NULL); | |
793 | } | |
794 | } else | |
795 | retval = uart_startup(state, 1); | |
796 | exit: | |
797 | up(&state->sem); | |
798 | return retval; | |
799 | } | |
800 | ||
801 | ||
802 | /* | |
803 | * uart_get_lsr_info - get line status register info. | |
804 | * Note: uart_ioctl protects us against hangups. | |
805 | */ | |
806 | static int uart_get_lsr_info(struct uart_state *state, | |
807 | unsigned int __user *value) | |
808 | { | |
809 | struct uart_port *port = state->port; | |
810 | unsigned int result; | |
811 | ||
812 | result = port->ops->tx_empty(port); | |
813 | ||
814 | /* | |
815 | * If we're about to load something into the transmit | |
816 | * register, we'll pretend the transmitter isn't empty to | |
817 | * avoid a race condition (depending on when the transmit | |
818 | * interrupt happens). | |
819 | */ | |
820 | if (port->x_char || | |
821 | ((uart_circ_chars_pending(&state->info->xmit) > 0) && | |
822 | !state->info->tty->stopped && !state->info->tty->hw_stopped)) | |
823 | result &= ~TIOCSER_TEMT; | |
824 | ||
825 | return put_user(result, value); | |
826 | } | |
827 | ||
828 | static int uart_tiocmget(struct tty_struct *tty, struct file *file) | |
829 | { | |
830 | struct uart_state *state = tty->driver_data; | |
831 | struct uart_port *port = state->port; | |
832 | int result = -EIO; | |
833 | ||
834 | down(&state->sem); | |
835 | if ((!file || !tty_hung_up_p(file)) && | |
836 | !(tty->flags & (1 << TTY_IO_ERROR))) { | |
837 | result = port->mctrl; | |
c5f4644e RK |
838 | |
839 | spin_lock_irq(&port->lock); | |
1da177e4 | 840 | result |= port->ops->get_mctrl(port); |
c5f4644e | 841 | spin_unlock_irq(&port->lock); |
1da177e4 LT |
842 | } |
843 | up(&state->sem); | |
844 | ||
845 | return result; | |
846 | } | |
847 | ||
848 | static int | |
849 | uart_tiocmset(struct tty_struct *tty, struct file *file, | |
850 | unsigned int set, unsigned int clear) | |
851 | { | |
852 | struct uart_state *state = tty->driver_data; | |
853 | struct uart_port *port = state->port; | |
854 | int ret = -EIO; | |
855 | ||
856 | down(&state->sem); | |
857 | if ((!file || !tty_hung_up_p(file)) && | |
858 | !(tty->flags & (1 << TTY_IO_ERROR))) { | |
859 | uart_update_mctrl(port, set, clear); | |
860 | ret = 0; | |
861 | } | |
862 | up(&state->sem); | |
863 | return ret; | |
864 | } | |
865 | ||
866 | static void uart_break_ctl(struct tty_struct *tty, int break_state) | |
867 | { | |
868 | struct uart_state *state = tty->driver_data; | |
869 | struct uart_port *port = state->port; | |
870 | ||
871 | BUG_ON(!kernel_locked()); | |
872 | ||
873 | down(&state->sem); | |
874 | ||
875 | if (port->type != PORT_UNKNOWN) | |
876 | port->ops->break_ctl(port, break_state); | |
877 | ||
878 | up(&state->sem); | |
879 | } | |
880 | ||
881 | static int uart_do_autoconfig(struct uart_state *state) | |
882 | { | |
883 | struct uart_port *port = state->port; | |
884 | int flags, ret; | |
885 | ||
886 | if (!capable(CAP_SYS_ADMIN)) | |
887 | return -EPERM; | |
888 | ||
889 | /* | |
890 | * Take the per-port semaphore. This prevents count from | |
891 | * changing, and hence any extra opens of the port while | |
892 | * we're auto-configuring. | |
893 | */ | |
894 | if (down_interruptible(&state->sem)) | |
895 | return -ERESTARTSYS; | |
896 | ||
897 | ret = -EBUSY; | |
898 | if (uart_users(state) == 1) { | |
899 | uart_shutdown(state); | |
900 | ||
901 | /* | |
902 | * If we already have a port type configured, | |
903 | * we must release its resources. | |
904 | */ | |
905 | if (port->type != PORT_UNKNOWN) | |
906 | port->ops->release_port(port); | |
907 | ||
908 | flags = UART_CONFIG_TYPE; | |
909 | if (port->flags & UPF_AUTO_IRQ) | |
910 | flags |= UART_CONFIG_IRQ; | |
911 | ||
912 | /* | |
913 | * This will claim the ports resources if | |
914 | * a port is found. | |
915 | */ | |
916 | port->ops->config_port(port, flags); | |
917 | ||
918 | ret = uart_startup(state, 1); | |
919 | } | |
920 | up(&state->sem); | |
921 | return ret; | |
922 | } | |
923 | ||
924 | /* | |
925 | * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change | |
926 | * - mask passed in arg for lines of interest | |
927 | * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking) | |
928 | * Caller should use TIOCGICOUNT to see which one it was | |
929 | */ | |
930 | static int | |
931 | uart_wait_modem_status(struct uart_state *state, unsigned long arg) | |
932 | { | |
933 | struct uart_port *port = state->port; | |
934 | DECLARE_WAITQUEUE(wait, current); | |
935 | struct uart_icount cprev, cnow; | |
936 | int ret; | |
937 | ||
938 | /* | |
939 | * note the counters on entry | |
940 | */ | |
941 | spin_lock_irq(&port->lock); | |
942 | memcpy(&cprev, &port->icount, sizeof(struct uart_icount)); | |
943 | ||
944 | /* | |
945 | * Force modem status interrupts on | |
946 | */ | |
947 | port->ops->enable_ms(port); | |
948 | spin_unlock_irq(&port->lock); | |
949 | ||
950 | add_wait_queue(&state->info->delta_msr_wait, &wait); | |
951 | for (;;) { | |
952 | spin_lock_irq(&port->lock); | |
953 | memcpy(&cnow, &port->icount, sizeof(struct uart_icount)); | |
954 | spin_unlock_irq(&port->lock); | |
955 | ||
956 | set_current_state(TASK_INTERRUPTIBLE); | |
957 | ||
958 | if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) || | |
959 | ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) || | |
960 | ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) || | |
961 | ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) { | |
962 | ret = 0; | |
963 | break; | |
964 | } | |
965 | ||
966 | schedule(); | |
967 | ||
968 | /* see if a signal did it */ | |
969 | if (signal_pending(current)) { | |
970 | ret = -ERESTARTSYS; | |
971 | break; | |
972 | } | |
973 | ||
974 | cprev = cnow; | |
975 | } | |
976 | ||
977 | current->state = TASK_RUNNING; | |
978 | remove_wait_queue(&state->info->delta_msr_wait, &wait); | |
979 | ||
980 | return ret; | |
981 | } | |
982 | ||
983 | /* | |
984 | * Get counter of input serial line interrupts (DCD,RI,DSR,CTS) | |
985 | * Return: write counters to the user passed counter struct | |
986 | * NB: both 1->0 and 0->1 transitions are counted except for | |
987 | * RI where only 0->1 is counted. | |
988 | */ | |
989 | static int uart_get_count(struct uart_state *state, | |
990 | struct serial_icounter_struct __user *icnt) | |
991 | { | |
992 | struct serial_icounter_struct icount; | |
993 | struct uart_icount cnow; | |
994 | struct uart_port *port = state->port; | |
995 | ||
996 | spin_lock_irq(&port->lock); | |
997 | memcpy(&cnow, &port->icount, sizeof(struct uart_icount)); | |
998 | spin_unlock_irq(&port->lock); | |
999 | ||
1000 | icount.cts = cnow.cts; | |
1001 | icount.dsr = cnow.dsr; | |
1002 | icount.rng = cnow.rng; | |
1003 | icount.dcd = cnow.dcd; | |
1004 | icount.rx = cnow.rx; | |
1005 | icount.tx = cnow.tx; | |
1006 | icount.frame = cnow.frame; | |
1007 | icount.overrun = cnow.overrun; | |
1008 | icount.parity = cnow.parity; | |
1009 | icount.brk = cnow.brk; | |
1010 | icount.buf_overrun = cnow.buf_overrun; | |
1011 | ||
1012 | return copy_to_user(icnt, &icount, sizeof(icount)) ? -EFAULT : 0; | |
1013 | } | |
1014 | ||
1015 | /* | |
1016 | * Called via sys_ioctl under the BKL. We can use spin_lock_irq() here. | |
1017 | */ | |
1018 | static int | |
1019 | uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd, | |
1020 | unsigned long arg) | |
1021 | { | |
1022 | struct uart_state *state = tty->driver_data; | |
1023 | void __user *uarg = (void __user *)arg; | |
1024 | int ret = -ENOIOCTLCMD; | |
1025 | ||
1026 | BUG_ON(!kernel_locked()); | |
1027 | ||
1028 | /* | |
1029 | * These ioctls don't rely on the hardware to be present. | |
1030 | */ | |
1031 | switch (cmd) { | |
1032 | case TIOCGSERIAL: | |
1033 | ret = uart_get_info(state, uarg); | |
1034 | break; | |
1035 | ||
1036 | case TIOCSSERIAL: | |
1037 | ret = uart_set_info(state, uarg); | |
1038 | break; | |
1039 | ||
1040 | case TIOCSERCONFIG: | |
1041 | ret = uart_do_autoconfig(state); | |
1042 | break; | |
1043 | ||
1044 | case TIOCSERGWILD: /* obsolete */ | |
1045 | case TIOCSERSWILD: /* obsolete */ | |
1046 | ret = 0; | |
1047 | break; | |
1048 | } | |
1049 | ||
1050 | if (ret != -ENOIOCTLCMD) | |
1051 | goto out; | |
1052 | ||
1053 | if (tty->flags & (1 << TTY_IO_ERROR)) { | |
1054 | ret = -EIO; | |
1055 | goto out; | |
1056 | } | |
1057 | ||
1058 | /* | |
1059 | * The following should only be used when hardware is present. | |
1060 | */ | |
1061 | switch (cmd) { | |
1062 | case TIOCMIWAIT: | |
1063 | ret = uart_wait_modem_status(state, arg); | |
1064 | break; | |
1065 | ||
1066 | case TIOCGICOUNT: | |
1067 | ret = uart_get_count(state, uarg); | |
1068 | break; | |
1069 | } | |
1070 | ||
1071 | if (ret != -ENOIOCTLCMD) | |
1072 | goto out; | |
1073 | ||
1074 | down(&state->sem); | |
1075 | ||
1076 | if (tty_hung_up_p(filp)) { | |
1077 | ret = -EIO; | |
1078 | goto out_up; | |
1079 | } | |
1080 | ||
1081 | /* | |
1082 | * All these rely on hardware being present and need to be | |
1083 | * protected against the tty being hung up. | |
1084 | */ | |
1085 | switch (cmd) { | |
1086 | case TIOCSERGETLSR: /* Get line status register */ | |
1087 | ret = uart_get_lsr_info(state, uarg); | |
1088 | break; | |
1089 | ||
1090 | default: { | |
1091 | struct uart_port *port = state->port; | |
1092 | if (port->ops->ioctl) | |
1093 | ret = port->ops->ioctl(port, cmd, arg); | |
1094 | break; | |
1095 | } | |
1096 | } | |
1097 | out_up: | |
1098 | up(&state->sem); | |
1099 | out: | |
1100 | return ret; | |
1101 | } | |
1102 | ||
1103 | static void uart_set_termios(struct tty_struct *tty, struct termios *old_termios) | |
1104 | { | |
1105 | struct uart_state *state = tty->driver_data; | |
1106 | unsigned long flags; | |
1107 | unsigned int cflag = tty->termios->c_cflag; | |
1108 | ||
1109 | BUG_ON(!kernel_locked()); | |
1110 | ||
1111 | /* | |
1112 | * These are the bits that are used to setup various | |
1113 | * flags in the low level driver. | |
1114 | */ | |
1115 | #define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK)) | |
1116 | ||
1117 | if ((cflag ^ old_termios->c_cflag) == 0 && | |
1118 | RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0) | |
1119 | return; | |
1120 | ||
1121 | uart_change_speed(state, old_termios); | |
1122 | ||
1123 | /* Handle transition to B0 status */ | |
1124 | if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) | |
1125 | uart_clear_mctrl(state->port, TIOCM_RTS | TIOCM_DTR); | |
1126 | ||
1127 | /* Handle transition away from B0 status */ | |
1128 | if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { | |
1129 | unsigned int mask = TIOCM_DTR; | |
1130 | if (!(cflag & CRTSCTS) || | |
1131 | !test_bit(TTY_THROTTLED, &tty->flags)) | |
1132 | mask |= TIOCM_RTS; | |
1133 | uart_set_mctrl(state->port, mask); | |
1134 | } | |
1135 | ||
1136 | /* Handle turning off CRTSCTS */ | |
1137 | if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) { | |
1138 | spin_lock_irqsave(&state->port->lock, flags); | |
1139 | tty->hw_stopped = 0; | |
1140 | __uart_start(tty); | |
1141 | spin_unlock_irqrestore(&state->port->lock, flags); | |
1142 | } | |
1143 | ||
0dd7a1ae RK |
1144 | /* Handle turning on CRTSCTS */ |
1145 | if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) { | |
1146 | spin_lock_irqsave(&state->port->lock, flags); | |
1147 | if (!(state->port->ops->get_mctrl(state->port) & TIOCM_CTS)) { | |
1148 | tty->hw_stopped = 1; | |
1149 | state->port->ops->stop_tx(state->port, 0); | |
1150 | } | |
1151 | spin_unlock_irqrestore(&state->port->lock, flags); | |
1152 | } | |
1153 | ||
1da177e4 LT |
1154 | #if 0 |
1155 | /* | |
1156 | * No need to wake up processes in open wait, since they | |
1157 | * sample the CLOCAL flag once, and don't recheck it. | |
1158 | * XXX It's not clear whether the current behavior is correct | |
1159 | * or not. Hence, this may change..... | |
1160 | */ | |
1161 | if (!(old_termios->c_cflag & CLOCAL) && | |
1162 | (tty->termios->c_cflag & CLOCAL)) | |
1163 | wake_up_interruptible(&state->info->open_wait); | |
1164 | #endif | |
1165 | } | |
1166 | ||
1167 | /* | |
1168 | * In 2.4.5, calls to this will be serialized via the BKL in | |
1169 | * linux/drivers/char/tty_io.c:tty_release() | |
1170 | * linux/drivers/char/tty_io.c:do_tty_handup() | |
1171 | */ | |
1172 | static void uart_close(struct tty_struct *tty, struct file *filp) | |
1173 | { | |
1174 | struct uart_state *state = tty->driver_data; | |
1175 | struct uart_port *port; | |
1176 | ||
1177 | BUG_ON(!kernel_locked()); | |
1178 | ||
1179 | if (!state || !state->port) | |
1180 | return; | |
1181 | ||
1182 | port = state->port; | |
1183 | ||
1184 | DPRINTK("uart_close(%d) called\n", port->line); | |
1185 | ||
1186 | down(&state->sem); | |
1187 | ||
1188 | if (tty_hung_up_p(filp)) | |
1189 | goto done; | |
1190 | ||
1191 | if ((tty->count == 1) && (state->count != 1)) { | |
1192 | /* | |
1193 | * Uh, oh. tty->count is 1, which means that the tty | |
1194 | * structure will be freed. state->count should always | |
1195 | * be one in these conditions. If it's greater than | |
1196 | * one, we've got real problems, since it means the | |
1197 | * serial port won't be shutdown. | |
1198 | */ | |
1199 | printk(KERN_ERR "uart_close: bad serial port count; tty->count is 1, " | |
1200 | "state->count is %d\n", state->count); | |
1201 | state->count = 1; | |
1202 | } | |
1203 | if (--state->count < 0) { | |
1204 | printk(KERN_ERR "uart_close: bad serial port count for %s: %d\n", | |
1205 | tty->name, state->count); | |
1206 | state->count = 0; | |
1207 | } | |
1208 | if (state->count) | |
1209 | goto done; | |
1210 | ||
1211 | /* | |
1212 | * Now we wait for the transmit buffer to clear; and we notify | |
1213 | * the line discipline to only process XON/XOFF characters by | |
1214 | * setting tty->closing. | |
1215 | */ | |
1216 | tty->closing = 1; | |
1217 | ||
1218 | if (state->closing_wait != USF_CLOSING_WAIT_NONE) | |
1219 | tty_wait_until_sent(tty, msecs_to_jiffies(state->closing_wait)); | |
1220 | ||
1221 | /* | |
1222 | * At this point, we stop accepting input. To do this, we | |
1223 | * disable the receive line status interrupts. | |
1224 | */ | |
1225 | if (state->info->flags & UIF_INITIALIZED) { | |
1226 | unsigned long flags; | |
1227 | spin_lock_irqsave(&port->lock, flags); | |
1228 | port->ops->stop_rx(port); | |
1229 | spin_unlock_irqrestore(&port->lock, flags); | |
1230 | /* | |
1231 | * Before we drop DTR, make sure the UART transmitter | |
1232 | * has completely drained; this is especially | |
1233 | * important if there is a transmit FIFO! | |
1234 | */ | |
1235 | uart_wait_until_sent(tty, port->timeout); | |
1236 | } | |
1237 | ||
1238 | uart_shutdown(state); | |
1239 | uart_flush_buffer(tty); | |
1240 | ||
1241 | tty_ldisc_flush(tty); | |
1242 | ||
1243 | tty->closing = 0; | |
1244 | state->info->tty = NULL; | |
1245 | ||
1246 | if (state->info->blocked_open) { | |
1247 | if (state->close_delay) | |
1248 | msleep_interruptible(state->close_delay); | |
1249 | } else if (!uart_console(port)) { | |
1250 | uart_change_pm(state, 3); | |
1251 | } | |
1252 | ||
1253 | /* | |
1254 | * Wake up anyone trying to open this port. | |
1255 | */ | |
1256 | state->info->flags &= ~UIF_NORMAL_ACTIVE; | |
1257 | wake_up_interruptible(&state->info->open_wait); | |
1258 | ||
1259 | done: | |
1260 | up(&state->sem); | |
1261 | } | |
1262 | ||
1263 | static void uart_wait_until_sent(struct tty_struct *tty, int timeout) | |
1264 | { | |
1265 | struct uart_state *state = tty->driver_data; | |
1266 | struct uart_port *port = state->port; | |
1267 | unsigned long char_time, expire; | |
1268 | ||
1269 | BUG_ON(!kernel_locked()); | |
1270 | ||
1271 | if (port->type == PORT_UNKNOWN || port->fifosize == 0) | |
1272 | return; | |
1273 | ||
1274 | /* | |
1275 | * Set the check interval to be 1/5 of the estimated time to | |
1276 | * send a single character, and make it at least 1. The check | |
1277 | * interval should also be less than the timeout. | |
1278 | * | |
1279 | * Note: we have to use pretty tight timings here to satisfy | |
1280 | * the NIST-PCTS. | |
1281 | */ | |
1282 | char_time = (port->timeout - HZ/50) / port->fifosize; | |
1283 | char_time = char_time / 5; | |
1284 | if (char_time == 0) | |
1285 | char_time = 1; | |
1286 | if (timeout && timeout < char_time) | |
1287 | char_time = timeout; | |
1288 | ||
1289 | /* | |
1290 | * If the transmitter hasn't cleared in twice the approximate | |
1291 | * amount of time to send the entire FIFO, it probably won't | |
1292 | * ever clear. This assumes the UART isn't doing flow | |
1293 | * control, which is currently the case. Hence, if it ever | |
1294 | * takes longer than port->timeout, this is probably due to a | |
1295 | * UART bug of some kind. So, we clamp the timeout parameter at | |
1296 | * 2*port->timeout. | |
1297 | */ | |
1298 | if (timeout == 0 || timeout > 2 * port->timeout) | |
1299 | timeout = 2 * port->timeout; | |
1300 | ||
1301 | expire = jiffies + timeout; | |
1302 | ||
1303 | DPRINTK("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n", | |
1304 | port->line, jiffies, expire); | |
1305 | ||
1306 | /* | |
1307 | * Check whether the transmitter is empty every 'char_time'. | |
1308 | * 'timeout' / 'expire' give us the maximum amount of time | |
1309 | * we wait. | |
1310 | */ | |
1311 | while (!port->ops->tx_empty(port)) { | |
1312 | msleep_interruptible(jiffies_to_msecs(char_time)); | |
1313 | if (signal_pending(current)) | |
1314 | break; | |
1315 | if (time_after(jiffies, expire)) | |
1316 | break; | |
1317 | } | |
1318 | set_current_state(TASK_RUNNING); /* might not be needed */ | |
1319 | } | |
1320 | ||
1321 | /* | |
1322 | * This is called with the BKL held in | |
1323 | * linux/drivers/char/tty_io.c:do_tty_hangup() | |
1324 | * We're called from the eventd thread, so we can sleep for | |
1325 | * a _short_ time only. | |
1326 | */ | |
1327 | static void uart_hangup(struct tty_struct *tty) | |
1328 | { | |
1329 | struct uart_state *state = tty->driver_data; | |
1330 | ||
1331 | BUG_ON(!kernel_locked()); | |
1332 | DPRINTK("uart_hangup(%d)\n", state->port->line); | |
1333 | ||
1334 | down(&state->sem); | |
1335 | if (state->info && state->info->flags & UIF_NORMAL_ACTIVE) { | |
1336 | uart_flush_buffer(tty); | |
1337 | uart_shutdown(state); | |
1338 | state->count = 0; | |
1339 | state->info->flags &= ~UIF_NORMAL_ACTIVE; | |
1340 | state->info->tty = NULL; | |
1341 | wake_up_interruptible(&state->info->open_wait); | |
1342 | wake_up_interruptible(&state->info->delta_msr_wait); | |
1343 | } | |
1344 | up(&state->sem); | |
1345 | } | |
1346 | ||
1347 | /* | |
1348 | * Copy across the serial console cflag setting into the termios settings | |
1349 | * for the initial open of the port. This allows continuity between the | |
1350 | * kernel settings, and the settings init adopts when it opens the port | |
1351 | * for the first time. | |
1352 | */ | |
1353 | static void uart_update_termios(struct uart_state *state) | |
1354 | { | |
1355 | struct tty_struct *tty = state->info->tty; | |
1356 | struct uart_port *port = state->port; | |
1357 | ||
1358 | if (uart_console(port) && port->cons->cflag) { | |
1359 | tty->termios->c_cflag = port->cons->cflag; | |
1360 | port->cons->cflag = 0; | |
1361 | } | |
1362 | ||
1363 | /* | |
1364 | * If the device failed to grab its irq resources, | |
1365 | * or some other error occurred, don't try to talk | |
1366 | * to the port hardware. | |
1367 | */ | |
1368 | if (!(tty->flags & (1 << TTY_IO_ERROR))) { | |
1369 | /* | |
1370 | * Make termios settings take effect. | |
1371 | */ | |
1372 | uart_change_speed(state, NULL); | |
1373 | ||
1374 | /* | |
1375 | * And finally enable the RTS and DTR signals. | |
1376 | */ | |
1377 | if (tty->termios->c_cflag & CBAUD) | |
1378 | uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS); | |
1379 | } | |
1380 | } | |
1381 | ||
1382 | /* | |
1383 | * Block the open until the port is ready. We must be called with | |
1384 | * the per-port semaphore held. | |
1385 | */ | |
1386 | static int | |
1387 | uart_block_til_ready(struct file *filp, struct uart_state *state) | |
1388 | { | |
1389 | DECLARE_WAITQUEUE(wait, current); | |
1390 | struct uart_info *info = state->info; | |
1391 | struct uart_port *port = state->port; | |
c5f4644e | 1392 | unsigned int mctrl; |
1da177e4 LT |
1393 | |
1394 | info->blocked_open++; | |
1395 | state->count--; | |
1396 | ||
1397 | add_wait_queue(&info->open_wait, &wait); | |
1398 | while (1) { | |
1399 | set_current_state(TASK_INTERRUPTIBLE); | |
1400 | ||
1401 | /* | |
1402 | * If we have been hung up, tell userspace/restart open. | |
1403 | */ | |
1404 | if (tty_hung_up_p(filp) || info->tty == NULL) | |
1405 | break; | |
1406 | ||
1407 | /* | |
1408 | * If the port has been closed, tell userspace/restart open. | |
1409 | */ | |
1410 | if (!(info->flags & UIF_INITIALIZED)) | |
1411 | break; | |
1412 | ||
1413 | /* | |
1414 | * If non-blocking mode is set, or CLOCAL mode is set, | |
1415 | * we don't want to wait for the modem status lines to | |
1416 | * indicate that the port is ready. | |
1417 | * | |
1418 | * Also, if the port is not enabled/configured, we want | |
1419 | * to allow the open to succeed here. Note that we will | |
1420 | * have set TTY_IO_ERROR for a non-existant port. | |
1421 | */ | |
1422 | if ((filp->f_flags & O_NONBLOCK) || | |
1423 | (info->tty->termios->c_cflag & CLOCAL) || | |
1424 | (info->tty->flags & (1 << TTY_IO_ERROR))) { | |
1425 | break; | |
1426 | } | |
1427 | ||
1428 | /* | |
1429 | * Set DTR to allow modem to know we're waiting. Do | |
1430 | * not set RTS here - we want to make sure we catch | |
1431 | * the data from the modem. | |
1432 | */ | |
1433 | if (info->tty->termios->c_cflag & CBAUD) | |
1434 | uart_set_mctrl(port, TIOCM_DTR); | |
1435 | ||
1436 | /* | |
1437 | * and wait for the carrier to indicate that the | |
1438 | * modem is ready for us. | |
1439 | */ | |
c5f4644e RK |
1440 | spin_lock_irq(&port->lock); |
1441 | mctrl = port->ops->get_mctrl(port); | |
1442 | spin_unlock_irq(&port->lock); | |
1443 | if (mctrl & TIOCM_CAR) | |
1da177e4 LT |
1444 | break; |
1445 | ||
1446 | up(&state->sem); | |
1447 | schedule(); | |
1448 | down(&state->sem); | |
1449 | ||
1450 | if (signal_pending(current)) | |
1451 | break; | |
1452 | } | |
1453 | set_current_state(TASK_RUNNING); | |
1454 | remove_wait_queue(&info->open_wait, &wait); | |
1455 | ||
1456 | state->count++; | |
1457 | info->blocked_open--; | |
1458 | ||
1459 | if (signal_pending(current)) | |
1460 | return -ERESTARTSYS; | |
1461 | ||
1462 | if (!info->tty || tty_hung_up_p(filp)) | |
1463 | return -EAGAIN; | |
1464 | ||
1465 | return 0; | |
1466 | } | |
1467 | ||
1468 | static struct uart_state *uart_get(struct uart_driver *drv, int line) | |
1469 | { | |
1470 | struct uart_state *state; | |
1471 | ||
1472 | down(&port_sem); | |
1473 | state = drv->state + line; | |
1474 | if (down_interruptible(&state->sem)) { | |
1475 | state = ERR_PTR(-ERESTARTSYS); | |
1476 | goto out; | |
1477 | } | |
1478 | ||
1479 | state->count++; | |
1480 | if (!state->port) { | |
1481 | state->count--; | |
1482 | up(&state->sem); | |
1483 | state = ERR_PTR(-ENXIO); | |
1484 | goto out; | |
1485 | } | |
1486 | ||
1487 | if (!state->info) { | |
1488 | state->info = kmalloc(sizeof(struct uart_info), GFP_KERNEL); | |
1489 | if (state->info) { | |
1490 | memset(state->info, 0, sizeof(struct uart_info)); | |
1491 | init_waitqueue_head(&state->info->open_wait); | |
1492 | init_waitqueue_head(&state->info->delta_msr_wait); | |
1493 | ||
1494 | /* | |
1495 | * Link the info into the other structures. | |
1496 | */ | |
1497 | state->port->info = state->info; | |
1498 | ||
1499 | tasklet_init(&state->info->tlet, uart_tasklet_action, | |
1500 | (unsigned long)state); | |
1501 | } else { | |
1502 | state->count--; | |
1503 | up(&state->sem); | |
1504 | state = ERR_PTR(-ENOMEM); | |
1505 | } | |
1506 | } | |
1507 | ||
1508 | out: | |
1509 | up(&port_sem); | |
1510 | return state; | |
1511 | } | |
1512 | ||
1513 | /* | |
1514 | * In 2.4.5, calls to uart_open are serialised by the BKL in | |
1515 | * linux/fs/devices.c:chrdev_open() | |
1516 | * Note that if this fails, then uart_close() _will_ be called. | |
1517 | * | |
1518 | * In time, we want to scrap the "opening nonpresent ports" | |
1519 | * behaviour and implement an alternative way for setserial | |
1520 | * to set base addresses/ports/types. This will allow us to | |
1521 | * get rid of a certain amount of extra tests. | |
1522 | */ | |
1523 | static int uart_open(struct tty_struct *tty, struct file *filp) | |
1524 | { | |
1525 | struct uart_driver *drv = (struct uart_driver *)tty->driver->driver_state; | |
1526 | struct uart_state *state; | |
1527 | int retval, line = tty->index; | |
1528 | ||
1529 | BUG_ON(!kernel_locked()); | |
1530 | DPRINTK("uart_open(%d) called\n", line); | |
1531 | ||
1532 | /* | |
1533 | * tty->driver->num won't change, so we won't fail here with | |
1534 | * tty->driver_data set to something non-NULL (and therefore | |
1535 | * we won't get caught by uart_close()). | |
1536 | */ | |
1537 | retval = -ENODEV; | |
1538 | if (line >= tty->driver->num) | |
1539 | goto fail; | |
1540 | ||
1541 | /* | |
1542 | * We take the semaphore inside uart_get to guarantee that we won't | |
1543 | * be re-entered while allocating the info structure, or while we | |
1544 | * request any IRQs that the driver may need. This also has the nice | |
1545 | * side-effect that it delays the action of uart_hangup, so we can | |
1546 | * guarantee that info->tty will always contain something reasonable. | |
1547 | */ | |
1548 | state = uart_get(drv, line); | |
1549 | if (IS_ERR(state)) { | |
1550 | retval = PTR_ERR(state); | |
1551 | goto fail; | |
1552 | } | |
1553 | ||
1554 | /* | |
1555 | * Once we set tty->driver_data here, we are guaranteed that | |
1556 | * uart_close() will decrement the driver module use count. | |
1557 | * Any failures from here onwards should not touch the count. | |
1558 | */ | |
1559 | tty->driver_data = state; | |
1560 | tty->low_latency = (state->port->flags & UPF_LOW_LATENCY) ? 1 : 0; | |
1561 | tty->alt_speed = 0; | |
1562 | state->info->tty = tty; | |
1563 | ||
1564 | /* | |
1565 | * If the port is in the middle of closing, bail out now. | |
1566 | */ | |
1567 | if (tty_hung_up_p(filp)) { | |
1568 | retval = -EAGAIN; | |
1569 | state->count--; | |
1570 | up(&state->sem); | |
1571 | goto fail; | |
1572 | } | |
1573 | ||
1574 | /* | |
1575 | * Make sure the device is in D0 state. | |
1576 | */ | |
1577 | if (state->count == 1) | |
1578 | uart_change_pm(state, 0); | |
1579 | ||
1580 | /* | |
1581 | * Start up the serial port. | |
1582 | */ | |
1583 | retval = uart_startup(state, 0); | |
1584 | ||
1585 | /* | |
1586 | * If we succeeded, wait until the port is ready. | |
1587 | */ | |
1588 | if (retval == 0) | |
1589 | retval = uart_block_til_ready(filp, state); | |
1590 | up(&state->sem); | |
1591 | ||
1592 | /* | |
1593 | * If this is the first open to succeed, adjust things to suit. | |
1594 | */ | |
1595 | if (retval == 0 && !(state->info->flags & UIF_NORMAL_ACTIVE)) { | |
1596 | state->info->flags |= UIF_NORMAL_ACTIVE; | |
1597 | ||
1598 | uart_update_termios(state); | |
1599 | } | |
1600 | ||
1601 | fail: | |
1602 | return retval; | |
1603 | } | |
1604 | ||
1605 | static const char *uart_type(struct uart_port *port) | |
1606 | { | |
1607 | const char *str = NULL; | |
1608 | ||
1609 | if (port->ops->type) | |
1610 | str = port->ops->type(port); | |
1611 | ||
1612 | if (!str) | |
1613 | str = "unknown"; | |
1614 | ||
1615 | return str; | |
1616 | } | |
1617 | ||
1618 | #ifdef CONFIG_PROC_FS | |
1619 | ||
1620 | static int uart_line_info(char *buf, struct uart_driver *drv, int i) | |
1621 | { | |
1622 | struct uart_state *state = drv->state + i; | |
1623 | struct uart_port *port = state->port; | |
1624 | char stat_buf[32]; | |
1625 | unsigned int status; | |
1626 | int ret; | |
1627 | ||
1628 | if (!port) | |
1629 | return 0; | |
1630 | ||
1631 | ret = sprintf(buf, "%d: uart:%s %s%08lX irq:%d", | |
1632 | port->line, uart_type(port), | |
1633 | port->iotype == UPIO_MEM ? "mmio:0x" : "port:", | |
1634 | port->iotype == UPIO_MEM ? port->mapbase : | |
1635 | (unsigned long) port->iobase, | |
1636 | port->irq); | |
1637 | ||
1638 | if (port->type == PORT_UNKNOWN) { | |
1639 | strcat(buf, "\n"); | |
1640 | return ret + 1; | |
1641 | } | |
1642 | ||
1643 | if(capable(CAP_SYS_ADMIN)) | |
1644 | { | |
c5f4644e | 1645 | spin_lock_irq(&port->lock); |
1da177e4 | 1646 | status = port->ops->get_mctrl(port); |
c5f4644e | 1647 | spin_unlock_irq(&port->lock); |
1da177e4 LT |
1648 | |
1649 | ret += sprintf(buf + ret, " tx:%d rx:%d", | |
1650 | port->icount.tx, port->icount.rx); | |
1651 | if (port->icount.frame) | |
1652 | ret += sprintf(buf + ret, " fe:%d", | |
1653 | port->icount.frame); | |
1654 | if (port->icount.parity) | |
1655 | ret += sprintf(buf + ret, " pe:%d", | |
1656 | port->icount.parity); | |
1657 | if (port->icount.brk) | |
1658 | ret += sprintf(buf + ret, " brk:%d", | |
1659 | port->icount.brk); | |
1660 | if (port->icount.overrun) | |
1661 | ret += sprintf(buf + ret, " oe:%d", | |
1662 | port->icount.overrun); | |
1663 | ||
1664 | #define INFOBIT(bit,str) \ | |
1665 | if (port->mctrl & (bit)) \ | |
1666 | strncat(stat_buf, (str), sizeof(stat_buf) - \ | |
1667 | strlen(stat_buf) - 2) | |
1668 | #define STATBIT(bit,str) \ | |
1669 | if (status & (bit)) \ | |
1670 | strncat(stat_buf, (str), sizeof(stat_buf) - \ | |
1671 | strlen(stat_buf) - 2) | |
1672 | ||
1673 | stat_buf[0] = '\0'; | |
1674 | stat_buf[1] = '\0'; | |
1675 | INFOBIT(TIOCM_RTS, "|RTS"); | |
1676 | STATBIT(TIOCM_CTS, "|CTS"); | |
1677 | INFOBIT(TIOCM_DTR, "|DTR"); | |
1678 | STATBIT(TIOCM_DSR, "|DSR"); | |
1679 | STATBIT(TIOCM_CAR, "|CD"); | |
1680 | STATBIT(TIOCM_RNG, "|RI"); | |
1681 | if (stat_buf[0]) | |
1682 | stat_buf[0] = ' '; | |
1683 | strcat(stat_buf, "\n"); | |
1684 | ||
1685 | ret += sprintf(buf + ret, stat_buf); | |
1686 | } else { | |
1687 | strcat(buf, "\n"); | |
1688 | ret++; | |
1689 | } | |
1690 | #undef STATBIT | |
1691 | #undef INFOBIT | |
1692 | return ret; | |
1693 | } | |
1694 | ||
1695 | static int uart_read_proc(char *page, char **start, off_t off, | |
1696 | int count, int *eof, void *data) | |
1697 | { | |
1698 | struct tty_driver *ttydrv = data; | |
1699 | struct uart_driver *drv = ttydrv->driver_state; | |
1700 | int i, len = 0, l; | |
1701 | off_t begin = 0; | |
1702 | ||
1703 | len += sprintf(page, "serinfo:1.0 driver%s%s revision:%s\n", | |
1704 | "", "", ""); | |
1705 | for (i = 0; i < drv->nr && len < PAGE_SIZE - 96; i++) { | |
1706 | l = uart_line_info(page + len, drv, i); | |
1707 | len += l; | |
1708 | if (len + begin > off + count) | |
1709 | goto done; | |
1710 | if (len + begin < off) { | |
1711 | begin += len; | |
1712 | len = 0; | |
1713 | } | |
1714 | } | |
1715 | *eof = 1; | |
1716 | done: | |
1717 | if (off >= len + begin) | |
1718 | return 0; | |
1719 | *start = page + (off - begin); | |
1720 | return (count < begin + len - off) ? count : (begin + len - off); | |
1721 | } | |
1722 | #endif | |
1723 | ||
1724 | #ifdef CONFIG_SERIAL_CORE_CONSOLE | |
1725 | /* | |
1726 | * Check whether an invalid uart number has been specified, and | |
1727 | * if so, search for the first available port that does have | |
1728 | * console support. | |
1729 | */ | |
1730 | struct uart_port * __init | |
1731 | uart_get_console(struct uart_port *ports, int nr, struct console *co) | |
1732 | { | |
1733 | int idx = co->index; | |
1734 | ||
1735 | if (idx < 0 || idx >= nr || (ports[idx].iobase == 0 && | |
1736 | ports[idx].membase == NULL)) | |
1737 | for (idx = 0; idx < nr; idx++) | |
1738 | if (ports[idx].iobase != 0 || | |
1739 | ports[idx].membase != NULL) | |
1740 | break; | |
1741 | ||
1742 | co->index = idx; | |
1743 | ||
1744 | return ports + idx; | |
1745 | } | |
1746 | ||
1747 | /** | |
1748 | * uart_parse_options - Parse serial port baud/parity/bits/flow contro. | |
1749 | * @options: pointer to option string | |
1750 | * @baud: pointer to an 'int' variable for the baud rate. | |
1751 | * @parity: pointer to an 'int' variable for the parity. | |
1752 | * @bits: pointer to an 'int' variable for the number of data bits. | |
1753 | * @flow: pointer to an 'int' variable for the flow control character. | |
1754 | * | |
1755 | * uart_parse_options decodes a string containing the serial console | |
1756 | * options. The format of the string is <baud><parity><bits><flow>, | |
1757 | * eg: 115200n8r | |
1758 | */ | |
1759 | void __init | |
1760 | uart_parse_options(char *options, int *baud, int *parity, int *bits, int *flow) | |
1761 | { | |
1762 | char *s = options; | |
1763 | ||
1764 | *baud = simple_strtoul(s, NULL, 10); | |
1765 | while (*s >= '0' && *s <= '9') | |
1766 | s++; | |
1767 | if (*s) | |
1768 | *parity = *s++; | |
1769 | if (*s) | |
1770 | *bits = *s++ - '0'; | |
1771 | if (*s) | |
1772 | *flow = *s; | |
1773 | } | |
1774 | ||
1775 | struct baud_rates { | |
1776 | unsigned int rate; | |
1777 | unsigned int cflag; | |
1778 | }; | |
1779 | ||
1780 | static struct baud_rates baud_rates[] = { | |
1781 | { 921600, B921600 }, | |
1782 | { 460800, B460800 }, | |
1783 | { 230400, B230400 }, | |
1784 | { 115200, B115200 }, | |
1785 | { 57600, B57600 }, | |
1786 | { 38400, B38400 }, | |
1787 | { 19200, B19200 }, | |
1788 | { 9600, B9600 }, | |
1789 | { 4800, B4800 }, | |
1790 | { 2400, B2400 }, | |
1791 | { 1200, B1200 }, | |
1792 | { 0, B38400 } | |
1793 | }; | |
1794 | ||
1795 | /** | |
1796 | * uart_set_options - setup the serial console parameters | |
1797 | * @port: pointer to the serial ports uart_port structure | |
1798 | * @co: console pointer | |
1799 | * @baud: baud rate | |
1800 | * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even) | |
1801 | * @bits: number of data bits | |
1802 | * @flow: flow control character - 'r' (rts) | |
1803 | */ | |
1804 | int __init | |
1805 | uart_set_options(struct uart_port *port, struct console *co, | |
1806 | int baud, int parity, int bits, int flow) | |
1807 | { | |
1808 | struct termios termios; | |
1809 | int i; | |
1810 | ||
1811 | memset(&termios, 0, sizeof(struct termios)); | |
1812 | ||
1813 | termios.c_cflag = CREAD | HUPCL | CLOCAL; | |
1814 | ||
1815 | /* | |
1816 | * Construct a cflag setting. | |
1817 | */ | |
1818 | for (i = 0; baud_rates[i].rate; i++) | |
1819 | if (baud_rates[i].rate <= baud) | |
1820 | break; | |
1821 | ||
1822 | termios.c_cflag |= baud_rates[i].cflag; | |
1823 | ||
1824 | if (bits == 7) | |
1825 | termios.c_cflag |= CS7; | |
1826 | else | |
1827 | termios.c_cflag |= CS8; | |
1828 | ||
1829 | switch (parity) { | |
1830 | case 'o': case 'O': | |
1831 | termios.c_cflag |= PARODD; | |
1832 | /*fall through*/ | |
1833 | case 'e': case 'E': | |
1834 | termios.c_cflag |= PARENB; | |
1835 | break; | |
1836 | } | |
1837 | ||
1838 | if (flow == 'r') | |
1839 | termios.c_cflag |= CRTSCTS; | |
1840 | ||
1841 | port->ops->set_termios(port, &termios, NULL); | |
1842 | co->cflag = termios.c_cflag; | |
1843 | ||
1844 | return 0; | |
1845 | } | |
1846 | #endif /* CONFIG_SERIAL_CORE_CONSOLE */ | |
1847 | ||
1848 | static void uart_change_pm(struct uart_state *state, int pm_state) | |
1849 | { | |
1850 | struct uart_port *port = state->port; | |
1851 | if (port->ops->pm) | |
1852 | port->ops->pm(port, pm_state, state->pm_state); | |
1853 | state->pm_state = pm_state; | |
1854 | } | |
1855 | ||
1856 | int uart_suspend_port(struct uart_driver *drv, struct uart_port *port) | |
1857 | { | |
1858 | struct uart_state *state = drv->state + port->line; | |
1859 | ||
1860 | down(&state->sem); | |
1861 | ||
1862 | if (state->info && state->info->flags & UIF_INITIALIZED) { | |
1863 | struct uart_ops *ops = port->ops; | |
1864 | ||
1865 | spin_lock_irq(&port->lock); | |
1866 | ops->stop_tx(port, 0); | |
1867 | ops->set_mctrl(port, 0); | |
1868 | ops->stop_rx(port); | |
1869 | spin_unlock_irq(&port->lock); | |
1870 | ||
1871 | /* | |
1872 | * Wait for the transmitter to empty. | |
1873 | */ | |
1874 | while (!ops->tx_empty(port)) { | |
1875 | msleep(10); | |
1876 | } | |
1877 | ||
1878 | ops->shutdown(port); | |
1879 | } | |
1880 | ||
1881 | /* | |
1882 | * Disable the console device before suspending. | |
1883 | */ | |
1884 | if (uart_console(port)) | |
1885 | console_stop(port->cons); | |
1886 | ||
1887 | uart_change_pm(state, 3); | |
1888 | ||
1889 | up(&state->sem); | |
1890 | ||
1891 | return 0; | |
1892 | } | |
1893 | ||
1894 | int uart_resume_port(struct uart_driver *drv, struct uart_port *port) | |
1895 | { | |
1896 | struct uart_state *state = drv->state + port->line; | |
1897 | ||
1898 | down(&state->sem); | |
1899 | ||
1900 | uart_change_pm(state, 0); | |
1901 | ||
1902 | /* | |
1903 | * Re-enable the console device after suspending. | |
1904 | */ | |
1905 | if (uart_console(port)) { | |
1906 | struct termios termios; | |
1907 | ||
1908 | /* | |
1909 | * First try to use the console cflag setting. | |
1910 | */ | |
1911 | memset(&termios, 0, sizeof(struct termios)); | |
1912 | termios.c_cflag = port->cons->cflag; | |
1913 | ||
1914 | /* | |
1915 | * If that's unset, use the tty termios setting. | |
1916 | */ | |
1917 | if (state->info && state->info->tty && termios.c_cflag == 0) | |
1918 | termios = *state->info->tty->termios; | |
1919 | ||
1920 | port->ops->set_termios(port, &termios, NULL); | |
1921 | console_start(port->cons); | |
1922 | } | |
1923 | ||
1924 | if (state->info && state->info->flags & UIF_INITIALIZED) { | |
1925 | struct uart_ops *ops = port->ops; | |
1926 | ||
1927 | ops->set_mctrl(port, 0); | |
1928 | ops->startup(port); | |
1929 | uart_change_speed(state, NULL); | |
1930 | spin_lock_irq(&port->lock); | |
1931 | ops->set_mctrl(port, port->mctrl); | |
1932 | ops->start_tx(port, 0); | |
1933 | spin_unlock_irq(&port->lock); | |
1934 | } | |
1935 | ||
1936 | up(&state->sem); | |
1937 | ||
1938 | return 0; | |
1939 | } | |
1940 | ||
1941 | static inline void | |
1942 | uart_report_port(struct uart_driver *drv, struct uart_port *port) | |
1943 | { | |
1944 | printk("%s%d", drv->dev_name, port->line); | |
1945 | printk(" at "); | |
1946 | switch (port->iotype) { | |
1947 | case UPIO_PORT: | |
1948 | printk("I/O 0x%x", port->iobase); | |
1949 | break; | |
1950 | case UPIO_HUB6: | |
1951 | printk("I/O 0x%x offset 0x%x", port->iobase, port->hub6); | |
1952 | break; | |
1953 | case UPIO_MEM: | |
1954 | case UPIO_MEM32: | |
1955 | printk("MMIO 0x%lx", port->mapbase); | |
1956 | break; | |
1957 | } | |
1958 | printk(" (irq = %d) is a %s\n", port->irq, uart_type(port)); | |
1959 | } | |
1960 | ||
1961 | static void | |
1962 | uart_configure_port(struct uart_driver *drv, struct uart_state *state, | |
1963 | struct uart_port *port) | |
1964 | { | |
1965 | unsigned int flags; | |
1966 | ||
1967 | /* | |
1968 | * If there isn't a port here, don't do anything further. | |
1969 | */ | |
1970 | if (!port->iobase && !port->mapbase && !port->membase) | |
1971 | return; | |
1972 | ||
1973 | /* | |
1974 | * Now do the auto configuration stuff. Note that config_port | |
1975 | * is expected to claim the resources and map the port for us. | |
1976 | */ | |
1977 | flags = UART_CONFIG_TYPE; | |
1978 | if (port->flags & UPF_AUTO_IRQ) | |
1979 | flags |= UART_CONFIG_IRQ; | |
1980 | if (port->flags & UPF_BOOT_AUTOCONF) { | |
1981 | port->type = PORT_UNKNOWN; | |
1982 | port->ops->config_port(port, flags); | |
1983 | } | |
1984 | ||
1985 | if (port->type != PORT_UNKNOWN) { | |
1986 | unsigned long flags; | |
1987 | ||
1988 | uart_report_port(drv, port); | |
1989 | ||
1990 | /* | |
1991 | * Ensure that the modem control lines are de-activated. | |
1992 | * We probably don't need a spinlock around this, but | |
1993 | */ | |
1994 | spin_lock_irqsave(&port->lock, flags); | |
1995 | port->ops->set_mctrl(port, 0); | |
1996 | spin_unlock_irqrestore(&port->lock, flags); | |
1997 | ||
1998 | /* | |
1999 | * Power down all ports by default, except the | |
2000 | * console if we have one. | |
2001 | */ | |
2002 | if (!uart_console(port)) | |
2003 | uart_change_pm(state, 3); | |
2004 | } | |
2005 | } | |
2006 | ||
2007 | /* | |
2008 | * This reverses the effects of uart_configure_port, hanging up the | |
2009 | * port before removal. | |
2010 | */ | |
2011 | static void | |
2012 | uart_unconfigure_port(struct uart_driver *drv, struct uart_state *state) | |
2013 | { | |
2014 | struct uart_port *port = state->port; | |
2015 | struct uart_info *info = state->info; | |
2016 | ||
2017 | if (info && info->tty) | |
2018 | tty_vhangup(info->tty); | |
2019 | ||
2020 | down(&state->sem); | |
2021 | ||
2022 | state->info = NULL; | |
2023 | ||
2024 | /* | |
2025 | * Free the port IO and memory resources, if any. | |
2026 | */ | |
2027 | if (port->type != PORT_UNKNOWN) | |
2028 | port->ops->release_port(port); | |
2029 | ||
2030 | /* | |
2031 | * Indicate that there isn't a port here anymore. | |
2032 | */ | |
2033 | port->type = PORT_UNKNOWN; | |
2034 | ||
2035 | /* | |
2036 | * Kill the tasklet, and free resources. | |
2037 | */ | |
2038 | if (info) { | |
2039 | tasklet_kill(&info->tlet); | |
2040 | kfree(info); | |
2041 | } | |
2042 | ||
2043 | up(&state->sem); | |
2044 | } | |
2045 | ||
2046 | static struct tty_operations uart_ops = { | |
2047 | .open = uart_open, | |
2048 | .close = uart_close, | |
2049 | .write = uart_write, | |
2050 | .put_char = uart_put_char, | |
2051 | .flush_chars = uart_flush_chars, | |
2052 | .write_room = uart_write_room, | |
2053 | .chars_in_buffer= uart_chars_in_buffer, | |
2054 | .flush_buffer = uart_flush_buffer, | |
2055 | .ioctl = uart_ioctl, | |
2056 | .throttle = uart_throttle, | |
2057 | .unthrottle = uart_unthrottle, | |
2058 | .send_xchar = uart_send_xchar, | |
2059 | .set_termios = uart_set_termios, | |
2060 | .stop = uart_stop, | |
2061 | .start = uart_start, | |
2062 | .hangup = uart_hangup, | |
2063 | .break_ctl = uart_break_ctl, | |
2064 | .wait_until_sent= uart_wait_until_sent, | |
2065 | #ifdef CONFIG_PROC_FS | |
2066 | .read_proc = uart_read_proc, | |
2067 | #endif | |
2068 | .tiocmget = uart_tiocmget, | |
2069 | .tiocmset = uart_tiocmset, | |
2070 | }; | |
2071 | ||
2072 | /** | |
2073 | * uart_register_driver - register a driver with the uart core layer | |
2074 | * @drv: low level driver structure | |
2075 | * | |
2076 | * Register a uart driver with the core driver. We in turn register | |
2077 | * with the tty layer, and initialise the core driver per-port state. | |
2078 | * | |
2079 | * We have a proc file in /proc/tty/driver which is named after the | |
2080 | * normal driver. | |
2081 | * | |
2082 | * drv->port should be NULL, and the per-port structures should be | |
2083 | * registered using uart_add_one_port after this call has succeeded. | |
2084 | */ | |
2085 | int uart_register_driver(struct uart_driver *drv) | |
2086 | { | |
2087 | struct tty_driver *normal = NULL; | |
2088 | int i, retval; | |
2089 | ||
2090 | BUG_ON(drv->state); | |
2091 | ||
2092 | /* | |
2093 | * Maybe we should be using a slab cache for this, especially if | |
2094 | * we have a large number of ports to handle. | |
2095 | */ | |
2096 | drv->state = kmalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL); | |
2097 | retval = -ENOMEM; | |
2098 | if (!drv->state) | |
2099 | goto out; | |
2100 | ||
2101 | memset(drv->state, 0, sizeof(struct uart_state) * drv->nr); | |
2102 | ||
2103 | normal = alloc_tty_driver(drv->nr); | |
2104 | if (!normal) | |
2105 | goto out; | |
2106 | ||
2107 | drv->tty_driver = normal; | |
2108 | ||
2109 | normal->owner = drv->owner; | |
2110 | normal->driver_name = drv->driver_name; | |
2111 | normal->devfs_name = drv->devfs_name; | |
2112 | normal->name = drv->dev_name; | |
2113 | normal->major = drv->major; | |
2114 | normal->minor_start = drv->minor; | |
2115 | normal->type = TTY_DRIVER_TYPE_SERIAL; | |
2116 | normal->subtype = SERIAL_TYPE_NORMAL; | |
2117 | normal->init_termios = tty_std_termios; | |
2118 | normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; | |
2119 | normal->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS; | |
2120 | normal->driver_state = drv; | |
2121 | tty_set_operations(normal, &uart_ops); | |
2122 | ||
2123 | /* | |
2124 | * Initialise the UART state(s). | |
2125 | */ | |
2126 | for (i = 0; i < drv->nr; i++) { | |
2127 | struct uart_state *state = drv->state + i; | |
2128 | ||
2129 | state->close_delay = 500; /* .5 seconds */ | |
2130 | state->closing_wait = 30000; /* 30 seconds */ | |
2131 | ||
2132 | init_MUTEX(&state->sem); | |
2133 | } | |
2134 | ||
2135 | retval = tty_register_driver(normal); | |
2136 | out: | |
2137 | if (retval < 0) { | |
2138 | put_tty_driver(normal); | |
2139 | kfree(drv->state); | |
2140 | } | |
2141 | return retval; | |
2142 | } | |
2143 | ||
2144 | /** | |
2145 | * uart_unregister_driver - remove a driver from the uart core layer | |
2146 | * @drv: low level driver structure | |
2147 | * | |
2148 | * Remove all references to a driver from the core driver. The low | |
2149 | * level driver must have removed all its ports via the | |
2150 | * uart_remove_one_port() if it registered them with uart_add_one_port(). | |
2151 | * (ie, drv->port == NULL) | |
2152 | */ | |
2153 | void uart_unregister_driver(struct uart_driver *drv) | |
2154 | { | |
2155 | struct tty_driver *p = drv->tty_driver; | |
2156 | tty_unregister_driver(p); | |
2157 | put_tty_driver(p); | |
2158 | kfree(drv->state); | |
2159 | drv->tty_driver = NULL; | |
2160 | } | |
2161 | ||
2162 | struct tty_driver *uart_console_device(struct console *co, int *index) | |
2163 | { | |
2164 | struct uart_driver *p = co->data; | |
2165 | *index = co->index; | |
2166 | return p->tty_driver; | |
2167 | } | |
2168 | ||
2169 | /** | |
2170 | * uart_add_one_port - attach a driver-defined port structure | |
2171 | * @drv: pointer to the uart low level driver structure for this port | |
2172 | * @port: uart port structure to use for this port. | |
2173 | * | |
2174 | * This allows the driver to register its own uart_port structure | |
2175 | * with the core driver. The main purpose is to allow the low | |
2176 | * level uart drivers to expand uart_port, rather than having yet | |
2177 | * more levels of structures. | |
2178 | */ | |
2179 | int uart_add_one_port(struct uart_driver *drv, struct uart_port *port) | |
2180 | { | |
2181 | struct uart_state *state; | |
2182 | int ret = 0; | |
2183 | ||
2184 | BUG_ON(in_interrupt()); | |
2185 | ||
2186 | if (port->line >= drv->nr) | |
2187 | return -EINVAL; | |
2188 | ||
2189 | state = drv->state + port->line; | |
2190 | ||
2191 | down(&port_sem); | |
2192 | if (state->port) { | |
2193 | ret = -EINVAL; | |
2194 | goto out; | |
2195 | } | |
2196 | ||
2197 | state->port = port; | |
2198 | ||
2199 | spin_lock_init(&port->lock); | |
2200 | port->cons = drv->cons; | |
2201 | port->info = state->info; | |
2202 | ||
2203 | uart_configure_port(drv, state, port); | |
2204 | ||
2205 | /* | |
2206 | * Register the port whether it's detected or not. This allows | |
2207 | * setserial to be used to alter this ports parameters. | |
2208 | */ | |
2209 | tty_register_device(drv->tty_driver, port->line, port->dev); | |
2210 | ||
2211 | /* | |
2212 | * If this driver supports console, and it hasn't been | |
2213 | * successfully registered yet, try to re-register it. | |
2214 | * It may be that the port was not available. | |
2215 | */ | |
2216 | if (port->type != PORT_UNKNOWN && | |
2217 | port->cons && !(port->cons->flags & CON_ENABLED)) | |
2218 | register_console(port->cons); | |
2219 | ||
2220 | out: | |
2221 | up(&port_sem); | |
2222 | ||
2223 | return ret; | |
2224 | } | |
2225 | ||
2226 | /** | |
2227 | * uart_remove_one_port - detach a driver defined port structure | |
2228 | * @drv: pointer to the uart low level driver structure for this port | |
2229 | * @port: uart port structure for this port | |
2230 | * | |
2231 | * This unhooks (and hangs up) the specified port structure from the | |
2232 | * core driver. No further calls will be made to the low-level code | |
2233 | * for this port. | |
2234 | */ | |
2235 | int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port) | |
2236 | { | |
2237 | struct uart_state *state = drv->state + port->line; | |
2238 | ||
2239 | BUG_ON(in_interrupt()); | |
2240 | ||
2241 | if (state->port != port) | |
2242 | printk(KERN_ALERT "Removing wrong port: %p != %p\n", | |
2243 | state->port, port); | |
2244 | ||
2245 | down(&port_sem); | |
2246 | ||
2247 | /* | |
2248 | * Remove the devices from devfs | |
2249 | */ | |
2250 | tty_unregister_device(drv->tty_driver, port->line); | |
2251 | ||
2252 | uart_unconfigure_port(drv, state); | |
2253 | state->port = NULL; | |
2254 | up(&port_sem); | |
2255 | ||
2256 | return 0; | |
2257 | } | |
2258 | ||
2259 | /* | |
2260 | * Are the two ports equivalent? | |
2261 | */ | |
2262 | int uart_match_port(struct uart_port *port1, struct uart_port *port2) | |
2263 | { | |
2264 | if (port1->iotype != port2->iotype) | |
2265 | return 0; | |
2266 | ||
2267 | switch (port1->iotype) { | |
2268 | case UPIO_PORT: | |
2269 | return (port1->iobase == port2->iobase); | |
2270 | case UPIO_HUB6: | |
2271 | return (port1->iobase == port2->iobase) && | |
2272 | (port1->hub6 == port2->hub6); | |
2273 | case UPIO_MEM: | |
2274 | return (port1->membase == port2->membase); | |
2275 | } | |
2276 | return 0; | |
2277 | } | |
2278 | EXPORT_SYMBOL(uart_match_port); | |
2279 | ||
2280 | /* | |
2281 | * Try to find an unused uart_state slot for a port. | |
2282 | */ | |
2283 | static struct uart_state * | |
2284 | uart_find_match_or_unused(struct uart_driver *drv, struct uart_port *port) | |
2285 | { | |
2286 | int i; | |
2287 | ||
2288 | /* | |
2289 | * First, find a port entry which matches. Note: if we do | |
2290 | * find a matching entry, and it has a non-zero use count, | |
2291 | * then we can't register the port. | |
2292 | */ | |
2293 | for (i = 0; i < drv->nr; i++) | |
2294 | if (uart_match_port(drv->state[i].port, port)) | |
2295 | return &drv->state[i]; | |
2296 | ||
2297 | /* | |
2298 | * We didn't find a matching entry, so look for the first | |
2299 | * free entry. We look for one which hasn't been previously | |
2300 | * used (indicated by zero iobase). | |
2301 | */ | |
2302 | for (i = 0; i < drv->nr; i++) | |
2303 | if (drv->state[i].port->type == PORT_UNKNOWN && | |
2304 | drv->state[i].port->iobase == 0 && | |
2305 | drv->state[i].count == 0) | |
2306 | return &drv->state[i]; | |
2307 | ||
2308 | /* | |
2309 | * That also failed. Last resort is to find any currently | |
2310 | * entry which doesn't have a real port associated with it. | |
2311 | */ | |
2312 | for (i = 0; i < drv->nr; i++) | |
2313 | if (drv->state[i].port->type == PORT_UNKNOWN && | |
2314 | drv->state[i].count == 0) | |
2315 | return &drv->state[i]; | |
2316 | ||
2317 | return NULL; | |
2318 | } | |
2319 | ||
2320 | /** | |
2321 | * uart_register_port: register uart settings with a port | |
2322 | * @drv: pointer to the uart low level driver structure for this port | |
2323 | * @port: uart port structure describing the port | |
2324 | * | |
2325 | * Register UART settings with the specified low level driver. Detect | |
2326 | * the type of the port if UPF_BOOT_AUTOCONF is set, and detect the | |
2327 | * IRQ if UPF_AUTO_IRQ is set. | |
2328 | * | |
2329 | * We try to pick the same port for the same IO base address, so that | |
2330 | * when a modem is plugged in, unplugged and plugged back in, it gets | |
2331 | * allocated the same port. | |
2332 | * | |
2333 | * Returns negative error, or positive line number. | |
2334 | */ | |
2335 | int uart_register_port(struct uart_driver *drv, struct uart_port *port) | |
2336 | { | |
2337 | struct uart_state *state; | |
2338 | int ret; | |
2339 | ||
2340 | down(&port_sem); | |
2341 | ||
2342 | state = uart_find_match_or_unused(drv, port); | |
2343 | ||
2344 | if (state) { | |
2345 | /* | |
2346 | * Ok, we've found a line that we can use. | |
2347 | * | |
2348 | * If we find a port that matches this one, and it appears | |
2349 | * to be in-use (even if it doesn't have a type) we shouldn't | |
2350 | * alter it underneath itself - the port may be open and | |
2351 | * trying to do useful work. | |
2352 | */ | |
2353 | if (uart_users(state) != 0) { | |
2354 | ret = -EBUSY; | |
2355 | goto out; | |
2356 | } | |
2357 | ||
2358 | /* | |
2359 | * If the port is already initialised, don't touch it. | |
2360 | */ | |
2361 | if (state->port->type == PORT_UNKNOWN) { | |
2362 | state->port->iobase = port->iobase; | |
2363 | state->port->membase = port->membase; | |
2364 | state->port->irq = port->irq; | |
2365 | state->port->uartclk = port->uartclk; | |
2366 | state->port->fifosize = port->fifosize; | |
2367 | state->port->regshift = port->regshift; | |
2368 | state->port->iotype = port->iotype; | |
2369 | state->port->flags = port->flags; | |
2370 | state->port->line = state - drv->state; | |
2371 | state->port->mapbase = port->mapbase; | |
2372 | ||
2373 | uart_configure_port(drv, state, state->port); | |
2374 | } | |
2375 | ||
2376 | ret = state->port->line; | |
2377 | } else | |
2378 | ret = -ENOSPC; | |
2379 | out: | |
2380 | up(&port_sem); | |
2381 | return ret; | |
2382 | } | |
2383 | ||
2384 | /** | |
2385 | * uart_unregister_port - de-allocate a port | |
2386 | * @drv: pointer to the uart low level driver structure for this port | |
2387 | * @line: line index previously returned from uart_register_port() | |
2388 | * | |
2389 | * Hang up the specified line associated with the low level driver, | |
2390 | * and mark the port as unused. | |
2391 | */ | |
2392 | void uart_unregister_port(struct uart_driver *drv, int line) | |
2393 | { | |
2394 | struct uart_state *state; | |
2395 | ||
2396 | if (line < 0 || line >= drv->nr) { | |
2397 | printk(KERN_ERR "Attempt to unregister "); | |
2398 | printk("%s%d", drv->dev_name, line); | |
2399 | printk("\n"); | |
2400 | return; | |
2401 | } | |
2402 | ||
2403 | state = drv->state + line; | |
2404 | ||
2405 | down(&port_sem); | |
2406 | uart_unconfigure_port(drv, state); | |
2407 | up(&port_sem); | |
2408 | } | |
2409 | ||
2410 | EXPORT_SYMBOL(uart_write_wakeup); | |
2411 | EXPORT_SYMBOL(uart_register_driver); | |
2412 | EXPORT_SYMBOL(uart_unregister_driver); | |
2413 | EXPORT_SYMBOL(uart_suspend_port); | |
2414 | EXPORT_SYMBOL(uart_resume_port); | |
2415 | EXPORT_SYMBOL(uart_register_port); | |
2416 | EXPORT_SYMBOL(uart_unregister_port); | |
2417 | EXPORT_SYMBOL(uart_add_one_port); | |
2418 | EXPORT_SYMBOL(uart_remove_one_port); | |
2419 | ||
2420 | MODULE_DESCRIPTION("Serial driver core"); | |
2421 | MODULE_LICENSE("GPL"); |