1 /*
2 * generic_serial.c
3 *
4 * Copyright (C) 1998/1999 R.E.Wolff@BitWizard.nl
5 *
6 * written for the SX serial driver.
7 * Contains the code that should be shared over all the serial drivers.
8 *
9 * Credit for the idea to do it this way might go to Alan Cox.
10 *
11 *
12 * Version 0.1 -- December, 1998. Initial version.
13 * Version 0.2 -- March, 1999. Some more routines. Bugfixes. Etc.
14 * Version 0.5 -- August, 1999. Some more fixes. Reformat for Linus.
15 *
16 * BitWizard is actively maintaining this file. We sometimes find
17 * that someone submitted changes to this file. We really appreciate
18 * your help, but please submit changes through us. We're doing our
19 * best to be responsive. -- REW
20 * */
21
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/tty.h>
25 #include <linux/serial.h>
26 #include <linux/mm.h>
27 #include <linux/generic_serial.h>
28 #include <linux/interrupt.h>
29 #include <linux/tty_flip.h>
30 #include <linux/delay.h>
31 #include <asm/uaccess.h>
32
33 #define DEBUG
34
35 static int gs_debug;
36
37 #ifdef DEBUG
38 #define gs_dprintk(f, str...) if (gs_debug & f) printk (str)
39 #else
40 #define gs_dprintk(f, str...) /* nothing */
41 #endif
42
43 #define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter %s\n", __func__)
44 #define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit %s\n", __func__)
45
46 #define RS_EVENT_WRITE_WAKEUP 1
47
48 module_param(gs_debug, int, 0644);
49
50
51 int gs_put_char(struct tty_struct * tty, unsigned char ch)
52 {
53 struct gs_port *port;
54
55 func_enter ();
56
57 port = tty->driver_data;
58
59 if (!port) return 0;
60
61 if (! (port->port.flags & ASYNC_INITIALIZED)) return 0;
62
63 /* Take a lock on the serial tranmit buffer! */
64 mutex_lock(& port->port_write_mutex);
65
66 if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
67 /* Sorry, buffer is full, drop character. Update statistics???? -- REW */
68 mutex_unlock(&port->port_write_mutex);
69 return 0;
70 }
71
72 port->xmit_buf[port->xmit_head++] = ch;
73 port->xmit_head &= SERIAL_XMIT_SIZE - 1;
74 port->xmit_cnt++; /* Characters in buffer */
75
76 mutex_unlock(&port->port_write_mutex);
77 func_exit ();
78 return 1;
79 }
80
81
82 /*
83 > Problems to take into account are:
84 > -1- Interrupts that empty part of the buffer.
85 > -2- page faults on the access to userspace.
86 > -3- Other processes that are also trying to do a "write".
87 */
88
89 int gs_write(struct tty_struct * tty,
90 const unsigned char *buf, int count)
91 {
92 struct gs_port *port;
93 int c, total = 0;
94 int t;
95
96 func_enter ();
97
98 port = tty->driver_data;
99
100 if (!port) return 0;
101
102 if (! (port->port.flags & ASYNC_INITIALIZED))
103 return 0;
104
105 /* get exclusive "write" access to this port (problem 3) */
106 /* This is not a spinlock because we can have a disk access (page
107 fault) in copy_from_user */
108 mutex_lock(& port->port_write_mutex);
109
110 while (1) {
111
112 c = count;
113
114 /* This is safe because we "OWN" the "head". Noone else can
115 change the "head": we own the port_write_mutex. */
116 /* Don't overrun the end of the buffer */
117 t = SERIAL_XMIT_SIZE - port->xmit_head;
118 if (t < c) c = t;
119
120 /* This is safe because the xmit_cnt can only decrease. This
121 would increase "t", so we might copy too little chars. */
122 /* Don't copy past the "head" of the buffer */
123 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt;
124 if (t < c) c = t;
125
126 /* Can't copy more? break out! */
127 if (c <= 0) break;
128
129 memcpy (port->xmit_buf + port->xmit_head, buf, c);
130
131 port -> xmit_cnt += c;
132 port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1);
133 buf += c;
134 count -= c;
135 total += c;
136 }
137 mutex_unlock(& port->port_write_mutex);
138
139 gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n",
140 (port->port.flags & GS_TX_INTEN)?"enabled": "disabled");
141
142 if (port->xmit_cnt &&
143 !tty->stopped &&
144 !tty->hw_stopped &&
145 !(port->port.flags & GS_TX_INTEN)) {
146 port->port.flags |= GS_TX_INTEN;
147 port->rd->enable_tx_interrupts (port);
148 }
149 func_exit ();
150 return total;
151 }
152
153
154
155 int gs_write_room(struct tty_struct * tty)
156 {
157 struct gs_port *port = tty->driver_data;
158 int ret;
159
160 func_enter ();
161 ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
162 if (ret < 0)
163 ret = 0;
164 func_exit ();
165 return ret;
166 }
167
168
169 int gs_chars_in_buffer(struct tty_struct *tty)
170 {
171 struct gs_port *port = tty->driver_data;
172 func_enter ();
173
174 func_exit ();
175 return port->xmit_cnt;
176 }
177
178
179 static int gs_real_chars_in_buffer(struct tty_struct *tty)
180 {
181 struct gs_port *port;
182 func_enter ();
183
184 port = tty->driver_data;
185
186 if (!port->rd) return 0;
187 if (!port->rd->chars_in_buffer) return 0;
188
189 func_exit ();
190 return port->xmit_cnt + port->rd->chars_in_buffer (port);
191 }
192
193
194 static int gs_wait_tx_flushed (void * ptr, unsigned long timeout)
195 {
196 struct gs_port *port = ptr;
197 unsigned long end_jiffies;
198 int jiffies_to_transmit, charsleft = 0, rv = 0;
199 int rcib;
200
201 func_enter();
202
203 gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port);
204 if (port) {
205 gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n",
206 port->xmit_cnt, port->xmit_buf, port->port.tty);
207 }
208
209 if (!port || port->xmit_cnt < 0 || !port->xmit_buf) {
210 gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n");
211 func_exit();
212 return -EINVAL; /* This is an error which we don't know how to handle. */
213 }
214
215 rcib = gs_real_chars_in_buffer(port->port.tty);
216
217 if(rcib <= 0) {
218 gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n");
219 func_exit();
220 return rv;
221 }
222 /* stop trying: now + twice the time it would normally take + seconds */
223 if (timeout == 0) timeout = MAX_SCHEDULE_TIMEOUT;
224 end_jiffies = jiffies;
225 if (timeout != MAX_SCHEDULE_TIMEOUT)
226 end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0;
227 end_jiffies += timeout;
228
229 gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n",
230 jiffies, end_jiffies, end_jiffies-jiffies);
231
232 /* the expression is actually jiffies < end_jiffies, but that won't
233 work around the wraparound. Tricky eh? */
234 while ((charsleft = gs_real_chars_in_buffer (port->port.tty)) &&
235 time_after (end_jiffies, jiffies)) {
236 /* Units check:
237 chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies!
238 check! */
239
240 charsleft += 16; /* Allow 16 chars more to be transmitted ... */
241 jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0;
242 /* ^^^ Round up.... */
243 if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1;
244
245 gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies "
246 "(%d chars).\n", jiffies_to_transmit, charsleft);
247
248 msleep_interruptible(jiffies_to_msecs(jiffies_to_transmit));
249 if (signal_pending (current)) {
250 gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: ");
251 rv = -EINTR;
252 break;
253 }
254 }
255
256 gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft);
257 set_current_state (TASK_RUNNING);
258
259 func_exit();
260 return rv;
261 }
262
263
264
265 void gs_flush_buffer(struct tty_struct *tty)
266 {
267 struct gs_port *port;
268 unsigned long flags;
269
270 func_enter ();
271
272 port = tty->driver_data;
273
274 if (!port) return;
275
276 /* XXX Would the write semaphore do? */
277 spin_lock_irqsave (&port->driver_lock, flags);
278 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
279 spin_unlock_irqrestore (&port->driver_lock, flags);
280
281 tty_wakeup(tty);
282 func_exit ();
283 }
284
285
286 void gs_flush_chars(struct tty_struct * tty)
287 {
288 struct gs_port *port;
289
290 func_enter ();
291
292 port = tty->driver_data;
293
294 if (!port) return;
295
296 if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
297 !port->xmit_buf) {
298 func_exit ();
299 return;
300 }
301
302 /* Beats me -- REW */
303 port->port.flags |= GS_TX_INTEN;
304 port->rd->enable_tx_interrupts (port);
305 func_exit ();
306 }
307
308
309 void gs_stop(struct tty_struct * tty)
310 {
311 struct gs_port *port;
312
313 func_enter ();
314
315 port = tty->driver_data;
316
317 if (!port) return;
318
319 if (port->xmit_cnt &&
320 port->xmit_buf &&
321 (port->port.flags & GS_TX_INTEN) ) {
322 port->port.flags &= ~GS_TX_INTEN;
323 port->rd->disable_tx_interrupts (port);
324 }
325 func_exit ();
326 }
327
328
329 void gs_start(struct tty_struct * tty)
330 {
331 struct gs_port *port;
332
333 port = tty->driver_data;
334
335 if (!port) return;
336
337 if (port->xmit_cnt &&
338 port->xmit_buf &&
339 !(port->port.flags & GS_TX_INTEN) ) {
340 port->port.flags |= GS_TX_INTEN;
341 port->rd->enable_tx_interrupts (port);
342 }
343 func_exit ();
344 }
345
346
347 static void gs_shutdown_port (struct gs_port *port)
348 {
349 unsigned long flags;
350
351 func_enter();
352
353 if (!port) return;
354
355 if (!(port->port.flags & ASYNC_INITIALIZED))
356 return;
357
358 spin_lock_irqsave(&port->driver_lock, flags);
359
360 if (port->xmit_buf) {
361 free_page((unsigned long) port->xmit_buf);
362 port->xmit_buf = NULL;
363 }
364
365 if (port->port.tty)
366 set_bit(TTY_IO_ERROR, &port->port.tty->flags);
367
368 port->rd->shutdown_port (port);
369
370 port->port.flags &= ~ASYNC_INITIALIZED;
371 spin_unlock_irqrestore(&port->driver_lock, flags);
372
373 func_exit();
374 }
375
376
377 void gs_hangup(struct tty_struct *tty)
378 {
379 struct gs_port *port;
380 unsigned long flags;
381
382 func_enter ();
383
384 port = tty->driver_data;
385 tty = port->port.tty;
386 if (!tty)
387 return;
388
389 gs_shutdown_port (port);
390 spin_lock_irqsave(&port->port.lock, flags);
391 port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|GS_ACTIVE);
392 port->port.tty = NULL;
393 port->port.count = 0;
394 spin_unlock_irqrestore(&port->port.lock, flags);
395
396 wake_up_interruptible(&port->port.open_wait);
397 func_exit ();
398 }
399
400
401 int gs_block_til_ready(void *port_, struct file * filp)
402 {
403 struct gs_port *gp = port_;
404 struct tty_port *port = &gp->port;
405 DECLARE_WAITQUEUE(wait, current);
406 int retval;
407 int do_clocal = 0;
408 int CD;
409 struct tty_struct *tty;
410 unsigned long flags;
411
412 func_enter ();
413
414 if (!port) return 0;
415
416 tty = port->tty;
417
418 gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n");
419 /*
420 * If the device is in the middle of being closed, then block
421 * until it's done, and then try again.
422 */
423 if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
424 interruptible_sleep_on(&port->close_wait);
425 if (port->flags & ASYNC_HUP_NOTIFY)
426 return -EAGAIN;
427 else
428 return -ERESTARTSYS;
429 }
430
431 gs_dprintk (GS_DEBUG_BTR, "after hung up\n");
432
433 /*
434 * If non-blocking mode is set, or the port is not enabled,
435 * then make the check up front and then exit.
436 */
437 if ((filp->f_flags & O_NONBLOCK) ||
438 (tty->flags & (1 << TTY_IO_ERROR))) {
439 port->flags |= ASYNC_NORMAL_ACTIVE;
440 return 0;
441 }
442
443 gs_dprintk (GS_DEBUG_BTR, "after nonblock\n");
444
445 if (C_CLOCAL(tty))
446 do_clocal = 1;
447
448 /*
449 * Block waiting for the carrier detect and the line to become
450 * free (i.e., not in use by the callout). While we are in
451 * this loop, port->count is dropped by one, so that
452 * rs_close() knows when to free things. We restore it upon
453 * exit, either normal or abnormal.
454 */
455 retval = 0;
456
457 add_wait_queue(&port->open_wait, &wait);
458
459 gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n");
460 spin_lock_irqsave(&port->lock, flags);
461 if (!tty_hung_up_p(filp)) {
462 port->count--;
463 }
464 port->blocked_open++;
465 spin_unlock_irqrestore(&port->lock, flags);
466 while (1) {
467 CD = tty_port_carrier_raised(port);
468 gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
469 set_current_state (TASK_INTERRUPTIBLE);
470 if (tty_hung_up_p(filp) ||
471 !(port->flags & ASYNC_INITIALIZED)) {
472 if (port->flags & ASYNC_HUP_NOTIFY)
473 retval = -EAGAIN;
474 else
475 retval = -ERESTARTSYS;
476 break;
477 }
478 if (!(port->flags & ASYNC_CLOSING) &&
479 (do_clocal || CD))
480 break;
481 gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n",
482 (int)signal_pending (current), *(long*)(¤t->blocked));
483 if (signal_pending(current)) {
484 retval = -ERESTARTSYS;
485 break;
486 }
487 schedule();
488 }
489 gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
490 port->blocked_open);
491 set_current_state (TASK_RUNNING);
492 remove_wait_queue(&port->open_wait, &wait);
493
494 spin_lock_irqsave(&port->lock, flags);
495 if (!tty_hung_up_p(filp)) {
496 port->count++;
497 }
498 port->blocked_open--;
499 if (retval == 0)
500 port->flags |= ASYNC_NORMAL_ACTIVE;
501 spin_unlock_irqrestore(&port->lock, flags);
502 func_exit ();
503 return retval;
504 }
505
506
507 void gs_close(struct tty_struct * tty, struct file * filp)
508 {
509 unsigned long flags;
510 struct gs_port *port;
511
512 func_enter ();
513
514 port = tty->driver_data;
515
516 if (!port) return;
517
518 if (!port->port.tty) {
519 /* This seems to happen when this is called from vhangup. */
520 gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->port.tty is NULL\n");
521 port->port.tty = tty;
522 }
523
524 spin_lock_irqsave(&port->port.lock, flags);
525
526 if (tty_hung_up_p(filp)) {
527 spin_unlock_irqrestore(&port->port.lock, flags);
528 if (port->rd->hungup)
529 port->rd->hungup (port);
530 func_exit ();
531 return;
532 }
533
534 if ((tty->count == 1) && (port->port.count != 1)) {
535 printk(KERN_ERR "gs: gs_close port %p: bad port count;"
536 " tty->count is 1, port count is %d\n", port, port->port.count);
537 port->port.count = 1;
538 }
539 if (--port->port.count < 0) {
540 printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->port.count);
541 port->port.count = 0;
542 }
543
544 if (port->port.count) {
545 gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->port.count);
546 spin_unlock_irqrestore(&port->port.lock, flags);
547 func_exit ();
548 return;
549 }
550 port->port.flags |= ASYNC_CLOSING;
551
552 /*
553 * Now we wait for the transmit buffer to clear; and we notify
554 * the line discipline to only process XON/XOFF characters.
555 */
556 tty->closing = 1;
557 /* if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
558 tty_wait_until_sent(tty, port->closing_wait); */
559
560 /*
561 * At this point we stop accepting input. To do this, we
562 * disable the receive line status interrupts, and tell the
563 * interrupt driver to stop checking the data ready bit in the
564 * line status register.
565 */
566
567 spin_lock_irqsave(&port->driver_lock, flags);
568 port->rd->disable_rx_interrupts (port);
569 spin_unlock_irqrestore(&port->driver_lock, flags);
570 spin_unlock_irqrestore(&port->port.lock, flags);
571
572 /* close has no way of returning "EINTR", so discard return value */
573 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
574 gs_wait_tx_flushed (port, port->closing_wait);
575
576 port->port.flags &= ~GS_ACTIVE;
577
578 gs_flush_buffer(tty);
579
580 tty_ldisc_flush(tty);
581 tty->closing = 0;
582
583 spin_lock_irqsave(&port->driver_lock, flags);
584 port->event = 0;
585 port->rd->close (port);
586 port->rd->shutdown_port (port);
587 spin_unlock_irqrestore(&port->driver_lock, flags);
588
589 spin_lock_irqsave(&port->port.lock, flags);
590 port->port.tty = NULL;
591
592 if (port->port.blocked_open) {
593 if (port->close_delay) {
594 spin_unlock_irqrestore(&port->port.lock, flags);
595 msleep_interruptible(jiffies_to_msecs(port->close_delay));
596 spin_lock_irqsave(&port->port.lock, flags);
597 }
598 wake_up_interruptible(&port->port.open_wait);
599 }
600 port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED);
601 spin_unlock_irqrestore(&port->port.lock, flags);
602 wake_up_interruptible(&port->port.close_wait);
603
604 func_exit ();
605 }
606
607
608 void gs_set_termios (struct tty_struct * tty,
609 struct ktermios * old_termios)
610 {
611 struct gs_port *port;
612 int baudrate, tmp, rv;
613 struct ktermios *tiosp;
614
615 func_enter();
616
617 port = tty->driver_data;
618
619 if (!port) return;
620 if (!port->port.tty) {
621 /* This seems to happen when this is called after gs_close. */
622 gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->port.tty is NULL\n");
623 port->port.tty = tty;
624 }
625
626
627 tiosp = tty->termios;
628
629 if (gs_debug & GS_DEBUG_TERMIOS) {
630 gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp);
631 }
632
633 if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) {
634 if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n");
635 if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n");
636 if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n");
637 if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n");
638 if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n");
639 if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n");
640 }
641
642 baudrate = tty_get_baud_rate(tty);
643
644 if ((tiosp->c_cflag & CBAUD) == B38400) {
645 if ( (port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
646 baudrate = 57600;
647 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
648 baudrate = 115200;
649 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
650 baudrate = 230400;
651 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
652 baudrate = 460800;
653 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
654 baudrate = (port->baud_base / port->custom_divisor);
655 }
656
657 /* I recommend using THIS instead of the mess in termios (and
658 duplicating the above code). Next we should create a clean
659 interface towards this variable. If your card supports arbitrary
660 baud rates, (e.g. CD1400 or 16550 based cards) then everything
661 will be very easy..... */
662 port->baud = baudrate;
663
664 /* Two timer ticks seems enough to wakeup something like SLIP driver */
665 /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */
666 tmp = (baudrate / 10 / HZ) * 2;
667
668 if (tmp < 0) tmp = 0;
669 if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1;
670
671 port->wakeup_chars = tmp;
672
673 /* We should really wait for the characters to be all sent before
674 changing the settings. -- CAL */
675 rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT);
676 if (rv < 0) return /* rv */;
677
678 rv = port->rd->set_real_termios(port);
679 if (rv < 0) return /* rv */;
680
681 if ((!old_termios ||
682 (old_termios->c_cflag & CRTSCTS)) &&
683 !( tiosp->c_cflag & CRTSCTS)) {
684 tty->stopped = 0;
685 gs_start(tty);
686 }
687
688 #ifdef tytso_patch_94Nov25_1726
689 /* This "makes sense", Why is it commented out? */
690
691 if (!(old_termios->c_cflag & CLOCAL) &&
692 (tty->termios->c_cflag & CLOCAL))
693 wake_up_interruptible(&port->gs.open_wait);
694 #endif
695
696 func_exit();
697 return /* 0 */;
698 }
699
700
701
702 /* Must be called with interrupts enabled */
703 int gs_init_port(struct gs_port *port)
704 {
705 unsigned long flags;
706
707 func_enter ();
708
709 if (port->port.flags & ASYNC_INITIALIZED) {
710 func_exit ();
711 return 0;
712 }
713 if (!port->xmit_buf) {
714 /* We may sleep in get_zeroed_page() */
715 unsigned long tmp;
716
717 tmp = get_zeroed_page(GFP_KERNEL);
718 spin_lock_irqsave (&port->driver_lock, flags);
719 if (port->xmit_buf)
720 free_page (tmp);
721 else
722 port->xmit_buf = (unsigned char *) tmp;
723 spin_unlock_irqrestore(&port->driver_lock, flags);
724 if (!port->xmit_buf) {
725 func_exit ();
726 return -ENOMEM;
727 }
728 }
729
730 spin_lock_irqsave (&port->driver_lock, flags);
731 if (port->port.tty)
732 clear_bit(TTY_IO_ERROR, &port->port.tty->flags);
733 mutex_init(&port->port_write_mutex);
734 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
735 spin_unlock_irqrestore(&port->driver_lock, flags);
736 gs_set_termios(port->port.tty, NULL);
737 spin_lock_irqsave (&port->driver_lock, flags);
738 port->port.flags |= ASYNC_INITIALIZED;
739 port->port.flags &= ~GS_TX_INTEN;
740
741 spin_unlock_irqrestore(&port->driver_lock, flags);
742 func_exit ();
743 return 0;
744 }
745
746
747 int gs_setserial(struct gs_port *port, struct serial_struct __user *sp)
748 {
749 struct serial_struct sio;
750
751 if (copy_from_user(&sio, sp, sizeof(struct serial_struct)))
752 return(-EFAULT);
753
754 if (!capable(CAP_SYS_ADMIN)) {
755 if ((sio.baud_base != port->baud_base) ||
756 (sio.close_delay != port->close_delay) ||
757 ((sio.flags & ~ASYNC_USR_MASK) !=
758 (port->port.flags & ~ASYNC_USR_MASK)))
759 return(-EPERM);
760 }
761
762 port->port.flags = (port->port.flags & ~ASYNC_USR_MASK) |
763 (sio.flags & ASYNC_USR_MASK);
764
765 port->baud_base = sio.baud_base;
766 port->close_delay = sio.close_delay;
767 port->closing_wait = sio.closing_wait;
768 port->custom_divisor = sio.custom_divisor;
769
770 gs_set_termios (port->port.tty, NULL);
771
772 return 0;
773 }
774
775
776 /*****************************************************************************/
777
778 /*
779 * Generate the serial struct info.
780 */
781
782 int gs_getserial(struct gs_port *port, struct serial_struct __user *sp)
783 {
784 struct serial_struct sio;
785
786 memset(&sio, 0, sizeof(struct serial_struct));
787 sio.flags = port->port.flags;
788 sio.baud_base = port->baud_base;
789 sio.close_delay = port->close_delay;
790 sio.closing_wait = port->closing_wait;
791 sio.custom_divisor = port->custom_divisor;
792 sio.hub6 = 0;
793
794 /* If you want you can override these. */
795 sio.type = PORT_UNKNOWN;
796 sio.xmit_fifo_size = -1;
797 sio.line = -1;
798 sio.port = -1;
799 sio.irq = -1;
800
801 if (port->rd->getserial)
802 port->rd->getserial (port, &sio);
803
804 if (copy_to_user(sp, &sio, sizeof(struct serial_struct)))
805 return -EFAULT;
806 return 0;
807
808 }
809
810
811 void gs_got_break(struct gs_port *port)
812 {
813 func_enter ();
814
815 tty_insert_flip_char(port->port.tty, 0, TTY_BREAK);
816 tty_schedule_flip(port->port.tty);
817 if (port->port.flags & ASYNC_SAK) {
818 do_SAK (port->port.tty);
819 }
820
821 func_exit ();
822 }
823
824
825 EXPORT_SYMBOL(gs_put_char);
826 EXPORT_SYMBOL(gs_write);
827 EXPORT_SYMBOL(gs_write_room);
828 EXPORT_SYMBOL(gs_chars_in_buffer);
829 EXPORT_SYMBOL(gs_flush_buffer);
830 EXPORT_SYMBOL(gs_flush_chars);
831 EXPORT_SYMBOL(gs_stop);
832 EXPORT_SYMBOL(gs_start);
833 EXPORT_SYMBOL(gs_hangup);
834 EXPORT_SYMBOL(gs_block_til_ready);
835 EXPORT_SYMBOL(gs_close);
836 EXPORT_SYMBOL(gs_set_termios);
837 EXPORT_SYMBOL(gs_init_port);
838 EXPORT_SYMBOL(gs_setserial);
839 EXPORT_SYMBOL(gs_getserial);
840 EXPORT_SYMBOL(gs_got_break);
841
842 MODULE_LICENSE("GPL");
843
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