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-rw-r--r--drivers/char/generic_serial.c1001
1 files changed, 1001 insertions, 0 deletions
diff --git a/drivers/char/generic_serial.c b/drivers/char/generic_serial.c
new file mode 100644
index 000000000000..204a7302a4a9
--- /dev/null
+++ b/drivers/char/generic_serial.c
@@ -0,0 +1,1001 @@
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/semaphore.h>
32#include <asm/uaccess.h>
33
34#define DEBUG
35
36static char * tmp_buf;
37static DECLARE_MUTEX(tmp_buf_sem);
38
39static int gs_debug;
40
41#ifdef DEBUG
42#define gs_dprintk(f, str...) if (gs_debug & f) printk (str)
43#else
44#define gs_dprintk(f, str...) /* nothing */
45#endif
46
47#define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter %s\n", __FUNCTION__)
48#define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit %s\n", __FUNCTION__)
49#define NEW_WRITE_LOCKING 1
50#if NEW_WRITE_LOCKING
51#define DECL /* Nothing */
52#define LOCKIT down (& port->port_write_sem);
53#define RELEASEIT up (&port->port_write_sem);
54#else
55#define DECL unsigned long flags;
56#define LOCKIT save_flags (flags);cli ()
57#define RELEASEIT restore_flags (flags)
58#endif
59
60#define RS_EVENT_WRITE_WAKEUP 1
61
62module_param(gs_debug, int, 0644);
63
64
65void gs_put_char(struct tty_struct * tty, unsigned char ch)
66{
67 struct gs_port *port;
68 DECL
69
70 func_enter ();
71
72 if (!tty) return;
73
74 port = tty->driver_data;
75
76 if (!port) return;
77
78 if (! (port->flags & ASYNC_INITIALIZED)) return;
79
80 /* Take a lock on the serial tranmit buffer! */
81 LOCKIT;
82
83 if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
84 /* Sorry, buffer is full, drop character. Update statistics???? -- REW */
85 RELEASEIT;
86 return;
87 }
88
89 port->xmit_buf[port->xmit_head++] = ch;
90 port->xmit_head &= SERIAL_XMIT_SIZE - 1;
91 port->xmit_cnt++; /* Characters in buffer */
92
93 RELEASEIT;
94 func_exit ();
95}
96
97
98#ifdef NEW_WRITE_LOCKING
99
100/*
101> Problems to take into account are:
102> -1- Interrupts that empty part of the buffer.
103> -2- page faults on the access to userspace.
104> -3- Other processes that are also trying to do a "write".
105*/
106
107int gs_write(struct tty_struct * tty,
108 const unsigned char *buf, int count)
109{
110 struct gs_port *port;
111 int c, total = 0;
112 int t;
113
114 func_enter ();
115
116 if (!tty) return 0;
117
118 port = tty->driver_data;
119
120 if (!port) return 0;
121
122 if (! (port->flags & ASYNC_INITIALIZED))
123 return 0;
124
125 /* get exclusive "write" access to this port (problem 3) */
126 /* This is not a spinlock because we can have a disk access (page
127 fault) in copy_from_user */
128 down (& port->port_write_sem);
129
130 while (1) {
131
132 c = count;
133
134 /* This is safe because we "OWN" the "head". Noone else can
135 change the "head": we own the port_write_sem. */
136 /* Don't overrun the end of the buffer */
137 t = SERIAL_XMIT_SIZE - port->xmit_head;
138 if (t < c) c = t;
139
140 /* This is safe because the xmit_cnt can only decrease. This
141 would increase "t", so we might copy too little chars. */
142 /* Don't copy past the "head" of the buffer */
143 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt;
144 if (t < c) c = t;
145
146 /* Can't copy more? break out! */
147 if (c <= 0) break;
148
149 memcpy (port->xmit_buf + port->xmit_head, buf, c);
150
151 port -> xmit_cnt += c;
152 port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1);
153 buf += c;
154 count -= c;
155 total += c;
156 }
157 up (& port->port_write_sem);
158
159 gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n",
160 (port->flags & GS_TX_INTEN)?"enabled": "disabled");
161
162 if (port->xmit_cnt &&
163 !tty->stopped &&
164 !tty->hw_stopped &&
165 !(port->flags & GS_TX_INTEN)) {
166 port->flags |= GS_TX_INTEN;
167 port->rd->enable_tx_interrupts (port);
168 }
169 func_exit ();
170 return total;
171}
172#else
173/*
174> Problems to take into account are:
175> -1- Interrupts that empty part of the buffer.
176> -2- page faults on the access to userspace.
177> -3- Other processes that are also trying to do a "write".
178*/
179
180int gs_write(struct tty_struct * tty,
181 const unsigned char *buf, int count)
182{
183 struct gs_port *port;
184 int c, total = 0;
185 int t;
186 unsigned long flags;
187
188 func_enter ();
189
190 /* The standard serial driver returns 0 in this case.
191 That sounds to me as "No error, I just didn't get to writing any
192 bytes. Feel free to try again."
193 The "official" way to write n bytes from buf is:
194
195 for (nwritten = 0;nwritten < n;nwritten += rv) {
196 rv = write (fd, buf+nwritten, n-nwritten);
197 if (rv < 0) break; // Error: bail out. //
198 }
199
200 which will loop endlessly in this case. The manual page for write
201 agrees with me. In practise almost everybody writes
202 "write (fd, buf,n);" but some people might have had to deal with
203 incomplete writes in the past and correctly implemented it by now...
204 */
205
206 if (!tty) return -EIO;
207
208 port = tty->driver_data;
209 if (!port || !port->xmit_buf || !tmp_buf)
210 return -EIO;
211
212 local_save_flags(flags);
213 while (1) {
214 cli();
215 c = count;
216
217 /* This is safe because we "OWN" the "head". Noone else can
218 change the "head": we own the port_write_sem. */
219 /* Don't overrun the end of the buffer */
220 t = SERIAL_XMIT_SIZE - port->xmit_head;
221 if (t < c) c = t;
222
223 /* This is safe because the xmit_cnt can only decrease. This
224 would increase "t", so we might copy too little chars. */
225 /* Don't copy past the "head" of the buffer */
226 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt;
227 if (t < c) c = t;
228
229 /* Can't copy more? break out! */
230 if (c <= 0) {
231 local_restore_flags(flags);
232 break;
233 }
234 memcpy(port->xmit_buf + port->xmit_head, buf, c);
235 port->xmit_head = ((port->xmit_head + c) &
236 (SERIAL_XMIT_SIZE-1));
237 port->xmit_cnt += c;
238 local_restore_flags(flags);
239 buf += c;
240 count -= c;
241 total += c;
242 }
243
244 if (port->xmit_cnt &&
245 !tty->stopped &&
246 !tty->hw_stopped &&
247 !(port->flags & GS_TX_INTEN)) {
248 port->flags |= GS_TX_INTEN;
249 port->rd->enable_tx_interrupts (port);
250 }
251 func_exit ();
252 return total;
253}
254
255#endif
256
257
258
259int gs_write_room(struct tty_struct * tty)
260{
261 struct gs_port *port = tty->driver_data;
262 int ret;
263
264 func_enter ();
265 ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
266 if (ret < 0)
267 ret = 0;
268 func_exit ();
269 return ret;
270}
271
272
273int gs_chars_in_buffer(struct tty_struct *tty)
274{
275 struct gs_port *port = tty->driver_data;
276 func_enter ();
277
278 func_exit ();
279 return port->xmit_cnt;
280}
281
282
283static int gs_real_chars_in_buffer(struct tty_struct *tty)
284{
285 struct gs_port *port;
286 func_enter ();
287
288 if (!tty) return 0;
289 port = tty->driver_data;
290
291 if (!port->rd) return 0;
292 if (!port->rd->chars_in_buffer) return 0;
293
294 func_exit ();
295 return port->xmit_cnt + port->rd->chars_in_buffer (port);
296}
297
298
299static int gs_wait_tx_flushed (void * ptr, unsigned long timeout)
300{
301 struct gs_port *port = ptr;
302 unsigned long end_jiffies;
303 int jiffies_to_transmit, charsleft = 0, rv = 0;
304 int rcib;
305
306 func_enter();
307
308 gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port);
309 if (port) {
310 gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n",
311 port->xmit_cnt, port->xmit_buf, port->tty);
312 }
313
314 if (!port || port->xmit_cnt < 0 || !port->xmit_buf) {
315 gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n");
316 func_exit();
317 return -EINVAL; /* This is an error which we don't know how to handle. */
318 }
319
320 rcib = gs_real_chars_in_buffer(port->tty);
321
322 if(rcib <= 0) {
323 gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n");
324 func_exit();
325 return rv;
326 }
327 /* stop trying: now + twice the time it would normally take + seconds */
328 if (timeout == 0) timeout = MAX_SCHEDULE_TIMEOUT;
329 end_jiffies = jiffies;
330 if (timeout != MAX_SCHEDULE_TIMEOUT)
331 end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0;
332 end_jiffies += timeout;
333
334 gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n",
335 jiffies, end_jiffies, end_jiffies-jiffies);
336
337 /* the expression is actually jiffies < end_jiffies, but that won't
338 work around the wraparound. Tricky eh? */
339 while ((charsleft = gs_real_chars_in_buffer (port->tty)) &&
340 time_after (end_jiffies, jiffies)) {
341 /* Units check:
342 chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies!
343 check! */
344
345 charsleft += 16; /* Allow 16 chars more to be transmitted ... */
346 jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0;
347 /* ^^^ Round up.... */
348 if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1;
349
350 gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies "
351 "(%d chars).\n", jiffies_to_transmit, charsleft);
352
353 msleep_interruptible(jiffies_to_msecs(jiffies_to_transmit));
354 if (signal_pending (current)) {
355 gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: ");
356 rv = -EINTR;
357 break;
358 }
359 }
360
361 gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft);
362 set_current_state (TASK_RUNNING);
363
364 func_exit();
365 return rv;
366}
367
368
369
370void gs_flush_buffer(struct tty_struct *tty)
371{
372 struct gs_port *port;
373 unsigned long flags;
374
375 func_enter ();
376
377 if (!tty) return;
378
379 port = tty->driver_data;
380
381 if (!port) return;
382
383 /* XXX Would the write semaphore do? */
384 spin_lock_irqsave (&port->driver_lock, flags);
385 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
386 spin_unlock_irqrestore (&port->driver_lock, flags);
387
388 wake_up_interruptible(&tty->write_wait);
389 tty_wakeup(tty);
390 func_exit ();
391}
392
393
394void gs_flush_chars(struct tty_struct * tty)
395{
396 struct gs_port *port;
397
398 func_enter ();
399
400 if (!tty) return;
401
402 port = tty->driver_data;
403
404 if (!port) return;
405
406 if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
407 !port->xmit_buf) {
408 func_exit ();
409 return;
410 }
411
412 /* Beats me -- REW */
413 port->flags |= GS_TX_INTEN;
414 port->rd->enable_tx_interrupts (port);
415 func_exit ();
416}
417
418
419void gs_stop(struct tty_struct * tty)
420{
421 struct gs_port *port;
422
423 func_enter ();
424
425 if (!tty) return;
426
427 port = tty->driver_data;
428
429 if (!port) return;
430
431 if (port->xmit_cnt &&
432 port->xmit_buf &&
433 (port->flags & GS_TX_INTEN) ) {
434 port->flags &= ~GS_TX_INTEN;
435 port->rd->disable_tx_interrupts (port);
436 }
437 func_exit ();
438}
439
440
441void gs_start(struct tty_struct * tty)
442{
443 struct gs_port *port;
444
445 if (!tty) return;
446
447 port = tty->driver_data;
448
449 if (!port) return;
450
451 if (port->xmit_cnt &&
452 port->xmit_buf &&
453 !(port->flags & GS_TX_INTEN) ) {
454 port->flags |= GS_TX_INTEN;
455 port->rd->enable_tx_interrupts (port);
456 }
457 func_exit ();
458}
459
460
461static void gs_shutdown_port (struct gs_port *port)
462{
463 unsigned long flags;
464
465 func_enter();
466
467 if (!port) return;
468
469 if (!(port->flags & ASYNC_INITIALIZED))
470 return;
471
472 spin_lock_irqsave(&port->driver_lock, flags);
473
474 if (port->xmit_buf) {
475 free_page((unsigned long) port->xmit_buf);
476 port->xmit_buf = NULL;
477 }
478
479 if (port->tty)
480 set_bit(TTY_IO_ERROR, &port->tty->flags);
481
482 port->rd->shutdown_port (port);
483
484 port->flags &= ~ASYNC_INITIALIZED;
485 spin_unlock_irqrestore(&port->driver_lock, flags);
486
487 func_exit();
488}
489
490
491void gs_hangup(struct tty_struct *tty)
492{
493 struct gs_port *port;
494
495 func_enter ();
496
497 if (!tty) return;
498
499 port = tty->driver_data;
500 tty = port->tty;
501 if (!tty)
502 return;
503
504 gs_shutdown_port (port);
505 port->flags &= ~(ASYNC_NORMAL_ACTIVE|GS_ACTIVE);
506 port->tty = NULL;
507 port->count = 0;
508
509 wake_up_interruptible(&port->open_wait);
510 func_exit ();
511}
512
513
514int gs_block_til_ready(void *port_, struct file * filp)
515{
516 struct gs_port *port = port_;
517 DECLARE_WAITQUEUE(wait, current);
518 int retval;
519 int do_clocal = 0;
520 int CD;
521 struct tty_struct *tty;
522 unsigned long flags;
523
524 func_enter ();
525
526 if (!port) return 0;
527
528 tty = port->tty;
529
530 if (!tty) return 0;
531
532 gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n");
533 /*
534 * If the device is in the middle of being closed, then block
535 * until it's done, and then try again.
536 */
537 if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
538 interruptible_sleep_on(&port->close_wait);
539 if (port->flags & ASYNC_HUP_NOTIFY)
540 return -EAGAIN;
541 else
542 return -ERESTARTSYS;
543 }
544
545 gs_dprintk (GS_DEBUG_BTR, "after hung up\n");
546
547 /*
548 * If non-blocking mode is set, or the port is not enabled,
549 * then make the check up front and then exit.
550 */
551 if ((filp->f_flags & O_NONBLOCK) ||
552 (tty->flags & (1 << TTY_IO_ERROR))) {
553 port->flags |= ASYNC_NORMAL_ACTIVE;
554 return 0;
555 }
556
557 gs_dprintk (GS_DEBUG_BTR, "after nonblock\n");
558
559 if (C_CLOCAL(tty))
560 do_clocal = 1;
561
562 /*
563 * Block waiting for the carrier detect and the line to become
564 * free (i.e., not in use by the callout). While we are in
565 * this loop, port->count is dropped by one, so that
566 * rs_close() knows when to free things. We restore it upon
567 * exit, either normal or abnormal.
568 */
569 retval = 0;
570
571 add_wait_queue(&port->open_wait, &wait);
572
573 gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n");
574 spin_lock_irqsave(&port->driver_lock, flags);
575 if (!tty_hung_up_p(filp)) {
576 port->count--;
577 }
578 spin_unlock_irqrestore(&port->driver_lock, flags);
579 port->blocked_open++;
580 while (1) {
581 CD = port->rd->get_CD (port);
582 gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
583 set_current_state (TASK_INTERRUPTIBLE);
584 if (tty_hung_up_p(filp) ||
585 !(port->flags & ASYNC_INITIALIZED)) {
586 if (port->flags & ASYNC_HUP_NOTIFY)
587 retval = -EAGAIN;
588 else
589 retval = -ERESTARTSYS;
590 break;
591 }
592 if (!(port->flags & ASYNC_CLOSING) &&
593 (do_clocal || CD))
594 break;
595 gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n",
596 (int)signal_pending (current), *(long*)(&current->blocked));
597 if (signal_pending(current)) {
598 retval = -ERESTARTSYS;
599 break;
600 }
601 schedule();
602 }
603 gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
604 port->blocked_open);
605 set_current_state (TASK_RUNNING);
606 remove_wait_queue(&port->open_wait, &wait);
607 if (!tty_hung_up_p(filp)) {
608 port->count++;
609 }
610 port->blocked_open--;
611 if (retval)
612 return retval;
613
614 port->flags |= ASYNC_NORMAL_ACTIVE;
615 func_exit ();
616 return 0;
617}
618
619
620void gs_close(struct tty_struct * tty, struct file * filp)
621{
622 unsigned long flags;
623 struct gs_port *port;
624
625 func_enter ();
626
627 if (!tty) return;
628
629 port = (struct gs_port *) tty->driver_data;
630
631 if (!port) return;
632
633 if (!port->tty) {
634 /* This seems to happen when this is called from vhangup. */
635 gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->tty is NULL\n");
636 port->tty = tty;
637 }
638
639 spin_lock_irqsave(&port->driver_lock, flags);
640
641 if (tty_hung_up_p(filp)) {
642 spin_unlock_irqrestore(&port->driver_lock, flags);
643 if (port->rd->hungup)
644 port->rd->hungup (port);
645 func_exit ();
646 return;
647 }
648
649 if ((tty->count == 1) && (port->count != 1)) {
650 printk(KERN_ERR "gs: gs_close port %p: bad port count;"
651 " tty->count is 1, port count is %d\n", port, port->count);
652 port->count = 1;
653 }
654 if (--port->count < 0) {
655 printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->count);
656 port->count = 0;
657 }
658
659 if (port->count) {
660 gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->count);
661 spin_unlock_irqrestore(&port->driver_lock, flags);
662 func_exit ();
663 return;
664 }
665 port->flags |= ASYNC_CLOSING;
666
667 /*
668 * Now we wait for the transmit buffer to clear; and we notify
669 * the line discipline to only process XON/XOFF characters.
670 */
671 tty->closing = 1;
672 /* if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
673 tty_wait_until_sent(tty, port->closing_wait); */
674
675 /*
676 * At this point we stop accepting input. To do this, we
677 * disable the receive line status interrupts, and tell the
678 * interrupt driver to stop checking the data ready bit in the
679 * line status register.
680 */
681
682 port->rd->disable_rx_interrupts (port);
683 spin_unlock_irqrestore(&port->driver_lock, flags);
684
685 /* close has no way of returning "EINTR", so discard return value */
686 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
687 gs_wait_tx_flushed (port, port->closing_wait);
688
689 port->flags &= ~GS_ACTIVE;
690
691 if (tty->driver->flush_buffer)
692 tty->driver->flush_buffer(tty);
693
694 tty_ldisc_flush(tty);
695 tty->closing = 0;
696
697 port->event = 0;
698 port->rd->close (port);
699 port->rd->shutdown_port (port);
700 port->tty = NULL;
701
702 if (port->blocked_open) {
703 if (port->close_delay) {
704 spin_unlock_irqrestore(&port->driver_lock, flags);
705 msleep_interruptible(jiffies_to_msecs(port->close_delay));
706 spin_lock_irqsave(&port->driver_lock, flags);
707 }
708 wake_up_interruptible(&port->open_wait);
709 }
710 port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED);
711 wake_up_interruptible(&port->close_wait);
712
713 func_exit ();
714}
715
716
717static unsigned int gs_baudrates[] = {
718 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
719 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600
720};
721
722
723void gs_set_termios (struct tty_struct * tty,
724 struct termios * old_termios)
725{
726 struct gs_port *port;
727 int baudrate, tmp, rv;
728 struct termios *tiosp;
729
730 func_enter();
731
732 if (!tty) return;
733
734 port = tty->driver_data;
735
736 if (!port) return;
737 if (!port->tty) {
738 /* This seems to happen when this is called after gs_close. */
739 gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->tty is NULL\n");
740 port->tty = tty;
741 }
742
743
744 tiosp = tty->termios;
745
746 if (gs_debug & GS_DEBUG_TERMIOS) {
747 gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp);
748 }
749
750#if 0
751 /* This is an optimization that is only allowed for dumb cards */
752 /* Smart cards require knowledge of iflags and oflags too: that
753 might change hardware cooking mode.... */
754#endif
755 if (old_termios) {
756 if( (tiosp->c_iflag == old_termios->c_iflag)
757 && (tiosp->c_oflag == old_termios->c_oflag)
758 && (tiosp->c_cflag == old_termios->c_cflag)
759 && (tiosp->c_lflag == old_termios->c_lflag)
760 && (tiosp->c_line == old_termios->c_line)
761 && (memcmp(tiosp->c_cc, old_termios->c_cc, NCC) == 0)) {
762 gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: optimized away\n");
763 return /* 0 */;
764 }
765 } else
766 gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: no old_termios: "
767 "no optimization\n");
768
769 if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) {
770 if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n");
771 if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n");
772 if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n");
773 if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n");
774 if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n");
775 if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n");
776 }
777
778 baudrate = tiosp->c_cflag & CBAUD;
779 if (baudrate & CBAUDEX) {
780 baudrate &= ~CBAUDEX;
781 if ((baudrate < 1) || (baudrate > 4))
782 tiosp->c_cflag &= ~CBAUDEX;
783 else
784 baudrate += 15;
785 }
786
787 baudrate = gs_baudrates[baudrate];
788 if ((tiosp->c_cflag & CBAUD) == B38400) {
789 if ( (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
790 baudrate = 57600;
791 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
792 baudrate = 115200;
793 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
794 baudrate = 230400;
795 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
796 baudrate = 460800;
797 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
798 baudrate = (port->baud_base / port->custom_divisor);
799 }
800
801 /* I recommend using THIS instead of the mess in termios (and
802 duplicating the above code). Next we should create a clean
803 interface towards this variable. If your card supports arbitrary
804 baud rates, (e.g. CD1400 or 16550 based cards) then everything
805 will be very easy..... */
806 port->baud = baudrate;
807
808 /* Two timer ticks seems enough to wakeup something like SLIP driver */
809 /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */
810 tmp = (baudrate / 10 / HZ) * 2;
811
812 if (tmp < 0) tmp = 0;
813 if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1;
814
815 port->wakeup_chars = tmp;
816
817 /* We should really wait for the characters to be all sent before
818 changing the settings. -- CAL */
819 rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT);
820 if (rv < 0) return /* rv */;
821
822 rv = port->rd->set_real_termios(port);
823 if (rv < 0) return /* rv */;
824
825 if ((!old_termios ||
826 (old_termios->c_cflag & CRTSCTS)) &&
827 !( tiosp->c_cflag & CRTSCTS)) {
828 tty->stopped = 0;
829 gs_start(tty);
830 }
831
832#ifdef tytso_patch_94Nov25_1726
833 /* This "makes sense", Why is it commented out? */
834
835 if (!(old_termios->c_cflag & CLOCAL) &&
836 (tty->termios->c_cflag & CLOCAL))
837 wake_up_interruptible(&port->gs.open_wait);
838#endif
839
840 func_exit();
841 return /* 0 */;
842}
843
844
845
846/* Must be called with interrupts enabled */
847int gs_init_port(struct gs_port *port)
848{
849 unsigned long flags;
850 unsigned long page;
851
852 func_enter ();
853
854 if (!tmp_buf) {
855 page = get_zeroed_page(GFP_KERNEL);
856 spin_lock_irqsave (&port->driver_lock, flags); /* Don't expect this to make a difference. */
857 if (tmp_buf)
858 free_page(page);
859 else
860 tmp_buf = (unsigned char *) page;
861 spin_unlock_irqrestore (&port->driver_lock, flags);
862 if (!tmp_buf) {
863 func_exit ();
864 return -ENOMEM;
865 }
866 }
867
868 if (port->flags & ASYNC_INITIALIZED) {
869 func_exit ();
870 return 0;
871 }
872 if (!port->xmit_buf) {
873 /* We may sleep in get_zeroed_page() */
874 unsigned long tmp;
875
876 tmp = get_zeroed_page(GFP_KERNEL);
877 spin_lock_irqsave (&port->driver_lock, flags);
878 if (port->xmit_buf)
879 free_page (tmp);
880 else
881 port->xmit_buf = (unsigned char *) tmp;
882 spin_unlock_irqrestore(&port->driver_lock, flags);
883 if (!port->xmit_buf) {
884 func_exit ();
885 return -ENOMEM;
886 }
887 }
888
889 spin_lock_irqsave (&port->driver_lock, flags);
890 if (port->tty)
891 clear_bit(TTY_IO_ERROR, &port->tty->flags);
892 init_MUTEX(&port->port_write_sem);
893 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
894 spin_unlock_irqrestore(&port->driver_lock, flags);
895 gs_set_termios(port->tty, NULL);
896 spin_lock_irqsave (&port->driver_lock, flags);
897 port->flags |= ASYNC_INITIALIZED;
898 port->flags &= ~GS_TX_INTEN;
899
900 spin_unlock_irqrestore(&port->driver_lock, flags);
901 func_exit ();
902 return 0;
903}
904
905
906int gs_setserial(struct gs_port *port, struct serial_struct __user *sp)
907{
908 struct serial_struct sio;
909
910 if (copy_from_user(&sio, sp, sizeof(struct serial_struct)))
911 return(-EFAULT);
912
913 if (!capable(CAP_SYS_ADMIN)) {
914 if ((sio.baud_base != port->baud_base) ||
915 (sio.close_delay != port->close_delay) ||
916 ((sio.flags & ~ASYNC_USR_MASK) !=
917 (port->flags & ~ASYNC_USR_MASK)))
918 return(-EPERM);
919 }
920
921 port->flags = (port->flags & ~ASYNC_USR_MASK) |
922 (sio.flags & ASYNC_USR_MASK);
923
924 port->baud_base = sio.baud_base;
925 port->close_delay = sio.close_delay;
926 port->closing_wait = sio.closing_wait;
927 port->custom_divisor = sio.custom_divisor;
928
929 gs_set_termios (port->tty, NULL);
930
931 return 0;
932}
933
934
935/*****************************************************************************/
936
937/*
938 * Generate the serial struct info.
939 */
940
941int gs_getserial(struct gs_port *port, struct serial_struct __user *sp)
942{
943 struct serial_struct sio;
944
945 memset(&sio, 0, sizeof(struct serial_struct));
946 sio.flags = port->flags;
947 sio.baud_base = port->baud_base;
948 sio.close_delay = port->close_delay;
949 sio.closing_wait = port->closing_wait;
950 sio.custom_divisor = port->custom_divisor;
951 sio.hub6 = 0;
952
953 /* If you want you can override these. */
954 sio.type = PORT_UNKNOWN;
955 sio.xmit_fifo_size = -1;
956 sio.line = -1;
957 sio.port = -1;
958 sio.irq = -1;
959
960 if (port->rd->getserial)
961 port->rd->getserial (port, &sio);
962
963 if (copy_to_user(sp, &sio, sizeof(struct serial_struct)))
964 return -EFAULT;
965 return 0;
966
967}
968
969
970void gs_got_break(struct gs_port *port)
971{
972 func_enter ();
973
974 tty_insert_flip_char(port->tty, 0, TTY_BREAK);
975 tty_schedule_flip(port->tty);
976 if (port->flags & ASYNC_SAK) {
977 do_SAK (port->tty);
978 }
979
980 func_exit ();
981}
982
983
984EXPORT_SYMBOL(gs_put_char);
985EXPORT_SYMBOL(gs_write);
986EXPORT_SYMBOL(gs_write_room);
987EXPORT_SYMBOL(gs_chars_in_buffer);
988EXPORT_SYMBOL(gs_flush_buffer);
989EXPORT_SYMBOL(gs_flush_chars);
990EXPORT_SYMBOL(gs_stop);
991EXPORT_SYMBOL(gs_start);
992EXPORT_SYMBOL(gs_hangup);
993EXPORT_SYMBOL(gs_block_til_ready);
994EXPORT_SYMBOL(gs_close);
995EXPORT_SYMBOL(gs_set_termios);
996EXPORT_SYMBOL(gs_init_port);
997EXPORT_SYMBOL(gs_setserial);
998EXPORT_SYMBOL(gs_getserial);
999EXPORT_SYMBOL(gs_got_break);
1000
1001MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-25 21:30:12 -0500