blob: 19d3afb0e50c5854d466bcee013217c0d52c64b3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <asm/uaccess.h>
32
33#define DEBUG
34
Linus Torvalds1da177e2005-04-16 15:20:36 -070035static 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
Harvey Harrisonbf9d8922008-04-30 00:55:10 -070043#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__)
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46#define RS_EVENT_WRITE_WAKEUP 1
47
48module_param(gs_debug, int, 0644);
49
50
Alan Cox76b25a52008-04-30 00:54:03 -070051int gs_put_char(struct tty_struct * tty, unsigned char ch)
Linus Torvalds1da177e2005-04-16 15:20:36 -070052{
53 struct gs_port *port;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
55 func_enter ();
56
Alan Cox76b25a52008-04-30 00:54:03 -070057 if (!tty) return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
59 port = tty->driver_data;
60
Alan Cox76b25a52008-04-30 00:54:03 -070061 if (!port) return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070062
Alan Coxb5391e22008-07-16 21:55:20 +010063 if (! (port->port.flags & ASYNC_INITIALIZED)) return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65 /* Take a lock on the serial tranmit buffer! */
Alan Cox35426122007-07-15 23:41:47 -070066 mutex_lock(& port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
68 if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
69 /* Sorry, buffer is full, drop character. Update statistics???? -- REW */
Alan Cox35426122007-07-15 23:41:47 -070070 mutex_unlock(&port->port_write_mutex);
Alan Cox76b25a52008-04-30 00:54:03 -070071 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 }
73
74 port->xmit_buf[port->xmit_head++] = ch;
75 port->xmit_head &= SERIAL_XMIT_SIZE - 1;
76 port->xmit_cnt++; /* Characters in buffer */
77
Alan Cox35426122007-07-15 23:41:47 -070078 mutex_unlock(&port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 func_exit ();
Alan Cox76b25a52008-04-30 00:54:03 -070080 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081}
82
83
Linus Torvalds1da177e2005-04-16 15:20:36 -070084/*
85> Problems to take into account are:
86> -1- Interrupts that empty part of the buffer.
87> -2- page faults on the access to userspace.
88> -3- Other processes that are also trying to do a "write".
89*/
90
91int gs_write(struct tty_struct * tty,
92 const unsigned char *buf, int count)
93{
94 struct gs_port *port;
95 int c, total = 0;
96 int t;
97
98 func_enter ();
99
100 if (!tty) return 0;
101
102 port = tty->driver_data;
103
104 if (!port) return 0;
105
Alan Coxb5391e22008-07-16 21:55:20 +0100106 if (! (port->port.flags & ASYNC_INITIALIZED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 return 0;
108
109 /* get exclusive "write" access to this port (problem 3) */
110 /* This is not a spinlock because we can have a disk access (page
111 fault) in copy_from_user */
Ingo Molnar81861d72006-03-23 03:00:44 -0800112 mutex_lock(& port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113
114 while (1) {
115
116 c = count;
117
118 /* This is safe because we "OWN" the "head". Noone else can
Ingo Molnar81861d72006-03-23 03:00:44 -0800119 change the "head": we own the port_write_mutex. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 /* Don't overrun the end of the buffer */
121 t = SERIAL_XMIT_SIZE - port->xmit_head;
122 if (t < c) c = t;
123
124 /* This is safe because the xmit_cnt can only decrease. This
125 would increase "t", so we might copy too little chars. */
126 /* Don't copy past the "head" of the buffer */
127 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt;
128 if (t < c) c = t;
129
130 /* Can't copy more? break out! */
131 if (c <= 0) break;
132
133 memcpy (port->xmit_buf + port->xmit_head, buf, c);
134
135 port -> xmit_cnt += c;
136 port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1);
137 buf += c;
138 count -= c;
139 total += c;
140 }
Ingo Molnar81861d72006-03-23 03:00:44 -0800141 mutex_unlock(& port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
143 gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n",
Alan Coxb5391e22008-07-16 21:55:20 +0100144 (port->port.flags & GS_TX_INTEN)?"enabled": "disabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145
146 if (port->xmit_cnt &&
147 !tty->stopped &&
148 !tty->hw_stopped &&
Alan Coxb5391e22008-07-16 21:55:20 +0100149 !(port->port.flags & GS_TX_INTEN)) {
150 port->port.flags |= GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 port->rd->enable_tx_interrupts (port);
152 }
153 func_exit ();
154 return total;
155}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
157
158
159int gs_write_room(struct tty_struct * tty)
160{
161 struct gs_port *port = tty->driver_data;
162 int ret;
163
164 func_enter ();
165 ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
166 if (ret < 0)
167 ret = 0;
168 func_exit ();
169 return ret;
170}
171
172
173int gs_chars_in_buffer(struct tty_struct *tty)
174{
175 struct gs_port *port = tty->driver_data;
176 func_enter ();
177
178 func_exit ();
179 return port->xmit_cnt;
180}
181
182
183static int gs_real_chars_in_buffer(struct tty_struct *tty)
184{
185 struct gs_port *port;
186 func_enter ();
187
188 if (!tty) return 0;
189 port = tty->driver_data;
190
191 if (!port->rd) return 0;
192 if (!port->rd->chars_in_buffer) return 0;
193
194 func_exit ();
195 return port->xmit_cnt + port->rd->chars_in_buffer (port);
196}
197
198
199static int gs_wait_tx_flushed (void * ptr, unsigned long timeout)
200{
201 struct gs_port *port = ptr;
202 unsigned long end_jiffies;
203 int jiffies_to_transmit, charsleft = 0, rv = 0;
204 int rcib;
205
206 func_enter();
207
208 gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port);
209 if (port) {
210 gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n",
Alan Coxb5391e22008-07-16 21:55:20 +0100211 port->xmit_cnt, port->xmit_buf, port->port.tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 }
213
214 if (!port || port->xmit_cnt < 0 || !port->xmit_buf) {
215 gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n");
216 func_exit();
217 return -EINVAL; /* This is an error which we don't know how to handle. */
218 }
219
Alan Coxb5391e22008-07-16 21:55:20 +0100220 rcib = gs_real_chars_in_buffer(port->port.tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221
222 if(rcib <= 0) {
223 gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n");
224 func_exit();
225 return rv;
226 }
227 /* stop trying: now + twice the time it would normally take + seconds */
228 if (timeout == 0) timeout = MAX_SCHEDULE_TIMEOUT;
229 end_jiffies = jiffies;
230 if (timeout != MAX_SCHEDULE_TIMEOUT)
231 end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0;
232 end_jiffies += timeout;
233
234 gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n",
235 jiffies, end_jiffies, end_jiffies-jiffies);
236
237 /* the expression is actually jiffies < end_jiffies, but that won't
238 work around the wraparound. Tricky eh? */
Alan Coxb5391e22008-07-16 21:55:20 +0100239 while ((charsleft = gs_real_chars_in_buffer (port->port.tty)) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 time_after (end_jiffies, jiffies)) {
241 /* Units check:
242 chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies!
243 check! */
244
245 charsleft += 16; /* Allow 16 chars more to be transmitted ... */
246 jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0;
247 /* ^^^ Round up.... */
248 if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1;
249
250 gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies "
251 "(%d chars).\n", jiffies_to_transmit, charsleft);
252
253 msleep_interruptible(jiffies_to_msecs(jiffies_to_transmit));
254 if (signal_pending (current)) {
255 gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: ");
256 rv = -EINTR;
257 break;
258 }
259 }
260
261 gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft);
262 set_current_state (TASK_RUNNING);
263
264 func_exit();
265 return rv;
266}
267
268
269
270void gs_flush_buffer(struct tty_struct *tty)
271{
272 struct gs_port *port;
273 unsigned long flags;
274
275 func_enter ();
276
277 if (!tty) return;
278
279 port = tty->driver_data;
280
281 if (!port) return;
282
283 /* XXX Would the write semaphore do? */
284 spin_lock_irqsave (&port->driver_lock, flags);
285 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
286 spin_unlock_irqrestore (&port->driver_lock, flags);
287
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 tty_wakeup(tty);
289 func_exit ();
290}
291
292
293void gs_flush_chars(struct tty_struct * tty)
294{
295 struct gs_port *port;
296
297 func_enter ();
298
299 if (!tty) return;
300
301 port = tty->driver_data;
302
303 if (!port) return;
304
305 if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
306 !port->xmit_buf) {
307 func_exit ();
308 return;
309 }
310
311 /* Beats me -- REW */
Alan Coxb5391e22008-07-16 21:55:20 +0100312 port->port.flags |= GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 port->rd->enable_tx_interrupts (port);
314 func_exit ();
315}
316
317
318void gs_stop(struct tty_struct * tty)
319{
320 struct gs_port *port;
321
322 func_enter ();
323
324 if (!tty) return;
325
326 port = tty->driver_data;
327
328 if (!port) return;
329
330 if (port->xmit_cnt &&
331 port->xmit_buf &&
Alan Coxb5391e22008-07-16 21:55:20 +0100332 (port->port.flags & GS_TX_INTEN) ) {
333 port->port.flags &= ~GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 port->rd->disable_tx_interrupts (port);
335 }
336 func_exit ();
337}
338
339
340void gs_start(struct tty_struct * tty)
341{
342 struct gs_port *port;
343
344 if (!tty) return;
345
346 port = tty->driver_data;
347
348 if (!port) return;
349
350 if (port->xmit_cnt &&
351 port->xmit_buf &&
Alan Coxb5391e22008-07-16 21:55:20 +0100352 !(port->port.flags & GS_TX_INTEN) ) {
353 port->port.flags |= GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 port->rd->enable_tx_interrupts (port);
355 }
356 func_exit ();
357}
358
359
360static void gs_shutdown_port (struct gs_port *port)
361{
362 unsigned long flags;
363
364 func_enter();
365
366 if (!port) return;
367
Alan Coxb5391e22008-07-16 21:55:20 +0100368 if (!(port->port.flags & ASYNC_INITIALIZED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 return;
370
371 spin_lock_irqsave(&port->driver_lock, flags);
372
373 if (port->xmit_buf) {
374 free_page((unsigned long) port->xmit_buf);
375 port->xmit_buf = NULL;
376 }
377
Alan Coxb5391e22008-07-16 21:55:20 +0100378 if (port->port.tty)
379 set_bit(TTY_IO_ERROR, &port->port.tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380
381 port->rd->shutdown_port (port);
382
Alan Coxb5391e22008-07-16 21:55:20 +0100383 port->port.flags &= ~ASYNC_INITIALIZED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 spin_unlock_irqrestore(&port->driver_lock, flags);
385
386 func_exit();
387}
388
389
390void gs_hangup(struct tty_struct *tty)
391{
392 struct gs_port *port;
393
394 func_enter ();
395
396 if (!tty) return;
397
398 port = tty->driver_data;
Alan Coxb5391e22008-07-16 21:55:20 +0100399 tty = port->port.tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 if (!tty)
401 return;
402
403 gs_shutdown_port (port);
Alan Coxb5391e22008-07-16 21:55:20 +0100404 port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|GS_ACTIVE);
405 port->port.tty = NULL;
406 port->port.count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407
Alan Coxb5391e22008-07-16 21:55:20 +0100408 wake_up_interruptible(&port->port.open_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 func_exit ();
410}
411
412
413int gs_block_til_ready(void *port_, struct file * filp)
414{
415 struct gs_port *port = port_;
416 DECLARE_WAITQUEUE(wait, current);
417 int retval;
418 int do_clocal = 0;
419 int CD;
420 struct tty_struct *tty;
421 unsigned long flags;
422
423 func_enter ();
424
425 if (!port) return 0;
426
Alan Coxb5391e22008-07-16 21:55:20 +0100427 tty = port->port.tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
429 if (!tty) return 0;
430
431 gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n");
432 /*
433 * If the device is in the middle of being closed, then block
434 * until it's done, and then try again.
435 */
Alan Coxb5391e22008-07-16 21:55:20 +0100436 if (tty_hung_up_p(filp) || port->port.flags & ASYNC_CLOSING) {
437 interruptible_sleep_on(&port->port.close_wait);
438 if (port->port.flags & ASYNC_HUP_NOTIFY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439 return -EAGAIN;
440 else
441 return -ERESTARTSYS;
442 }
443
444 gs_dprintk (GS_DEBUG_BTR, "after hung up\n");
445
446 /*
447 * If non-blocking mode is set, or the port is not enabled,
448 * then make the check up front and then exit.
449 */
450 if ((filp->f_flags & O_NONBLOCK) ||
451 (tty->flags & (1 << TTY_IO_ERROR))) {
Alan Coxb5391e22008-07-16 21:55:20 +0100452 port->port.flags |= ASYNC_NORMAL_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 return 0;
454 }
455
456 gs_dprintk (GS_DEBUG_BTR, "after nonblock\n");
457
458 if (C_CLOCAL(tty))
459 do_clocal = 1;
460
461 /*
462 * Block waiting for the carrier detect and the line to become
463 * free (i.e., not in use by the callout). While we are in
Alan Coxb5391e22008-07-16 21:55:20 +0100464 * this loop, port->port.count is dropped by one, so that
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 * rs_close() knows when to free things. We restore it upon
466 * exit, either normal or abnormal.
467 */
468 retval = 0;
469
Alan Coxb5391e22008-07-16 21:55:20 +0100470 add_wait_queue(&port->port.open_wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471
472 gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n");
473 spin_lock_irqsave(&port->driver_lock, flags);
474 if (!tty_hung_up_p(filp)) {
Alan Coxb5391e22008-07-16 21:55:20 +0100475 port->port.count--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 }
477 spin_unlock_irqrestore(&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100478 port->port.blocked_open++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 while (1) {
480 CD = port->rd->get_CD (port);
481 gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
482 set_current_state (TASK_INTERRUPTIBLE);
483 if (tty_hung_up_p(filp) ||
Alan Coxb5391e22008-07-16 21:55:20 +0100484 !(port->port.flags & ASYNC_INITIALIZED)) {
485 if (port->port.flags & ASYNC_HUP_NOTIFY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 retval = -EAGAIN;
487 else
488 retval = -ERESTARTSYS;
489 break;
490 }
Alan Coxb5391e22008-07-16 21:55:20 +0100491 if (!(port->port.flags & ASYNC_CLOSING) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 (do_clocal || CD))
493 break;
494 gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n",
495 (int)signal_pending (current), *(long*)(&current->blocked));
496 if (signal_pending(current)) {
497 retval = -ERESTARTSYS;
498 break;
499 }
500 schedule();
501 }
502 gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
Alan Coxb5391e22008-07-16 21:55:20 +0100503 port->port.blocked_open);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 set_current_state (TASK_RUNNING);
Alan Coxb5391e22008-07-16 21:55:20 +0100505 remove_wait_queue(&port->port.open_wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 if (!tty_hung_up_p(filp)) {
Alan Coxb5391e22008-07-16 21:55:20 +0100507 port->port.count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 }
Alan Coxb5391e22008-07-16 21:55:20 +0100509 port->port.blocked_open--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 if (retval)
511 return retval;
512
Alan Coxb5391e22008-07-16 21:55:20 +0100513 port->port.flags |= ASYNC_NORMAL_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 func_exit ();
515 return 0;
516}
517
518
519void gs_close(struct tty_struct * tty, struct file * filp)
520{
521 unsigned long flags;
522 struct gs_port *port;
523
524 func_enter ();
525
526 if (!tty) return;
527
528 port = (struct gs_port *) tty->driver_data;
529
530 if (!port) return;
531
Alan Coxb5391e22008-07-16 21:55:20 +0100532 if (!port->port.tty) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 /* This seems to happen when this is called from vhangup. */
Alan Coxb5391e22008-07-16 21:55:20 +0100534 gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->port.tty is NULL\n");
535 port->port.tty = tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 }
537
538 spin_lock_irqsave(&port->driver_lock, flags);
539
540 if (tty_hung_up_p(filp)) {
541 spin_unlock_irqrestore(&port->driver_lock, flags);
542 if (port->rd->hungup)
543 port->rd->hungup (port);
544 func_exit ();
545 return;
546 }
547
Alan Coxb5391e22008-07-16 21:55:20 +0100548 if ((tty->count == 1) && (port->port.count != 1)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 printk(KERN_ERR "gs: gs_close port %p: bad port count;"
Alan Coxb5391e22008-07-16 21:55:20 +0100550 " tty->count is 1, port count is %d\n", port, port->port.count);
551 port->port.count = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 }
Alan Coxb5391e22008-07-16 21:55:20 +0100553 if (--port->port.count < 0) {
554 printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->port.count);
555 port->port.count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 }
557
Alan Coxb5391e22008-07-16 21:55:20 +0100558 if (port->port.count) {
559 gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->port.count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 spin_unlock_irqrestore(&port->driver_lock, flags);
561 func_exit ();
562 return;
563 }
Alan Coxb5391e22008-07-16 21:55:20 +0100564 port->port.flags |= ASYNC_CLOSING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565
566 /*
567 * Now we wait for the transmit buffer to clear; and we notify
568 * the line discipline to only process XON/XOFF characters.
569 */
570 tty->closing = 1;
571 /* if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
572 tty_wait_until_sent(tty, port->closing_wait); */
573
574 /*
575 * At this point we stop accepting input. To do this, we
576 * disable the receive line status interrupts, and tell the
577 * interrupt driver to stop checking the data ready bit in the
578 * line status register.
579 */
580
581 port->rd->disable_rx_interrupts (port);
582 spin_unlock_irqrestore(&port->driver_lock, flags);
583
584 /* close has no way of returning "EINTR", so discard return value */
585 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
586 gs_wait_tx_flushed (port, port->closing_wait);
587
Alan Coxb5391e22008-07-16 21:55:20 +0100588 port->port.flags &= ~GS_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
Alan Cox978e5952008-04-30 00:53:59 -0700590 gs_flush_buffer(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591
592 tty_ldisc_flush(tty);
593 tty->closing = 0;
594
595 port->event = 0;
596 port->rd->close (port);
597 port->rd->shutdown_port (port);
Alan Coxb5391e22008-07-16 21:55:20 +0100598 port->port.tty = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
Alan Coxb5391e22008-07-16 21:55:20 +0100600 if (port->port.blocked_open) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 if (port->close_delay) {
602 spin_unlock_irqrestore(&port->driver_lock, flags);
603 msleep_interruptible(jiffies_to_msecs(port->close_delay));
604 spin_lock_irqsave(&port->driver_lock, flags);
605 }
Alan Coxb5391e22008-07-16 21:55:20 +0100606 wake_up_interruptible(&port->port.open_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 }
Alan Coxb5391e22008-07-16 21:55:20 +0100608 port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED);
609 wake_up_interruptible(&port->port.close_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610
611 func_exit ();
612}
613
614
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615void gs_set_termios (struct tty_struct * tty,
Alan Cox606d0992006-12-08 02:38:45 -0800616 struct ktermios * old_termios)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617{
618 struct gs_port *port;
619 int baudrate, tmp, rv;
Alan Cox606d0992006-12-08 02:38:45 -0800620 struct ktermios *tiosp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621
622 func_enter();
623
624 if (!tty) return;
625
626 port = tty->driver_data;
627
628 if (!port) return;
Alan Coxb5391e22008-07-16 21:55:20 +0100629 if (!port->port.tty) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 /* This seems to happen when this is called after gs_close. */
Alan Coxb5391e22008-07-16 21:55:20 +0100631 gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->port.tty is NULL\n");
632 port->port.tty = tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 }
634
635
636 tiosp = tty->termios;
637
638 if (gs_debug & GS_DEBUG_TERMIOS) {
639 gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp);
640 }
641
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) {
643 if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n");
644 if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n");
645 if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n");
646 if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n");
647 if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n");
648 if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n");
649 }
650
Alan Coxd720bc42006-09-29 02:01:38 -0700651 baudrate = tty_get_baud_rate(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653 if ((tiosp->c_cflag & CBAUD) == B38400) {
Alan Coxb5391e22008-07-16 21:55:20 +0100654 if ( (port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 baudrate = 57600;
Alan Coxb5391e22008-07-16 21:55:20 +0100656 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 baudrate = 115200;
Alan Coxb5391e22008-07-16 21:55:20 +0100658 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 baudrate = 230400;
Alan Coxb5391e22008-07-16 21:55:20 +0100660 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 baudrate = 460800;
Alan Coxb5391e22008-07-16 21:55:20 +0100662 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 baudrate = (port->baud_base / port->custom_divisor);
664 }
665
666 /* I recommend using THIS instead of the mess in termios (and
667 duplicating the above code). Next we should create a clean
668 interface towards this variable. If your card supports arbitrary
669 baud rates, (e.g. CD1400 or 16550 based cards) then everything
670 will be very easy..... */
671 port->baud = baudrate;
672
673 /* Two timer ticks seems enough to wakeup something like SLIP driver */
674 /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */
675 tmp = (baudrate / 10 / HZ) * 2;
676
677 if (tmp < 0) tmp = 0;
678 if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1;
679
680 port->wakeup_chars = tmp;
681
682 /* We should really wait for the characters to be all sent before
683 changing the settings. -- CAL */
684 rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT);
685 if (rv < 0) return /* rv */;
686
687 rv = port->rd->set_real_termios(port);
688 if (rv < 0) return /* rv */;
689
690 if ((!old_termios ||
691 (old_termios->c_cflag & CRTSCTS)) &&
692 !( tiosp->c_cflag & CRTSCTS)) {
693 tty->stopped = 0;
694 gs_start(tty);
695 }
696
697#ifdef tytso_patch_94Nov25_1726
698 /* This "makes sense", Why is it commented out? */
699
700 if (!(old_termios->c_cflag & CLOCAL) &&
701 (tty->termios->c_cflag & CLOCAL))
702 wake_up_interruptible(&port->gs.open_wait);
703#endif
704
705 func_exit();
706 return /* 0 */;
707}
708
709
710
711/* Must be called with interrupts enabled */
712int gs_init_port(struct gs_port *port)
713{
714 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715
716 func_enter ();
717
Alan Coxb5391e22008-07-16 21:55:20 +0100718 if (port->port.flags & ASYNC_INITIALIZED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719 func_exit ();
720 return 0;
721 }
722 if (!port->xmit_buf) {
723 /* We may sleep in get_zeroed_page() */
724 unsigned long tmp;
725
726 tmp = get_zeroed_page(GFP_KERNEL);
727 spin_lock_irqsave (&port->driver_lock, flags);
728 if (port->xmit_buf)
729 free_page (tmp);
730 else
731 port->xmit_buf = (unsigned char *) tmp;
732 spin_unlock_irqrestore(&port->driver_lock, flags);
733 if (!port->xmit_buf) {
734 func_exit ();
735 return -ENOMEM;
736 }
737 }
738
739 spin_lock_irqsave (&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100740 if (port->port.tty)
741 clear_bit(TTY_IO_ERROR, &port->port.tty->flags);
Ingo Molnar81861d72006-03-23 03:00:44 -0800742 mutex_init(&port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
744 spin_unlock_irqrestore(&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100745 gs_set_termios(port->port.tty, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 spin_lock_irqsave (&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100747 port->port.flags |= ASYNC_INITIALIZED;
748 port->port.flags &= ~GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749
750 spin_unlock_irqrestore(&port->driver_lock, flags);
751 func_exit ();
752 return 0;
753}
754
755
756int gs_setserial(struct gs_port *port, struct serial_struct __user *sp)
757{
758 struct serial_struct sio;
759
760 if (copy_from_user(&sio, sp, sizeof(struct serial_struct)))
761 return(-EFAULT);
762
763 if (!capable(CAP_SYS_ADMIN)) {
764 if ((sio.baud_base != port->baud_base) ||
765 (sio.close_delay != port->close_delay) ||
766 ((sio.flags & ~ASYNC_USR_MASK) !=
Alan Coxb5391e22008-07-16 21:55:20 +0100767 (port->port.flags & ~ASYNC_USR_MASK)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768 return(-EPERM);
769 }
770
Alan Coxb5391e22008-07-16 21:55:20 +0100771 port->port.flags = (port->port.flags & ~ASYNC_USR_MASK) |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 (sio.flags & ASYNC_USR_MASK);
773
774 port->baud_base = sio.baud_base;
775 port->close_delay = sio.close_delay;
776 port->closing_wait = sio.closing_wait;
777 port->custom_divisor = sio.custom_divisor;
778
Alan Coxb5391e22008-07-16 21:55:20 +0100779 gs_set_termios (port->port.tty, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780
781 return 0;
782}
783
784
785/*****************************************************************************/
786
787/*
788 * Generate the serial struct info.
789 */
790
791int gs_getserial(struct gs_port *port, struct serial_struct __user *sp)
792{
793 struct serial_struct sio;
794
795 memset(&sio, 0, sizeof(struct serial_struct));
Alan Coxb5391e22008-07-16 21:55:20 +0100796 sio.flags = port->port.flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 sio.baud_base = port->baud_base;
798 sio.close_delay = port->close_delay;
799 sio.closing_wait = port->closing_wait;
800 sio.custom_divisor = port->custom_divisor;
801 sio.hub6 = 0;
802
803 /* If you want you can override these. */
804 sio.type = PORT_UNKNOWN;
805 sio.xmit_fifo_size = -1;
806 sio.line = -1;
807 sio.port = -1;
808 sio.irq = -1;
809
810 if (port->rd->getserial)
811 port->rd->getserial (port, &sio);
812
813 if (copy_to_user(sp, &sio, sizeof(struct serial_struct)))
814 return -EFAULT;
815 return 0;
816
817}
818
819
820void gs_got_break(struct gs_port *port)
821{
822 func_enter ();
823
Alan Coxb5391e22008-07-16 21:55:20 +0100824 tty_insert_flip_char(port->port.tty, 0, TTY_BREAK);
825 tty_schedule_flip(port->port.tty);
826 if (port->port.flags & ASYNC_SAK) {
827 do_SAK (port->port.tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 }
829
830 func_exit ();
831}
832
833
834EXPORT_SYMBOL(gs_put_char);
835EXPORT_SYMBOL(gs_write);
836EXPORT_SYMBOL(gs_write_room);
837EXPORT_SYMBOL(gs_chars_in_buffer);
838EXPORT_SYMBOL(gs_flush_buffer);
839EXPORT_SYMBOL(gs_flush_chars);
840EXPORT_SYMBOL(gs_stop);
841EXPORT_SYMBOL(gs_start);
842EXPORT_SYMBOL(gs_hangup);
843EXPORT_SYMBOL(gs_block_til_ready);
844EXPORT_SYMBOL(gs_close);
845EXPORT_SYMBOL(gs_set_termios);
846EXPORT_SYMBOL(gs_init_port);
847EXPORT_SYMBOL(gs_setserial);
848EXPORT_SYMBOL(gs_getserial);
849EXPORT_SYMBOL(gs_got_break);
850
851MODULE_LICENSE("GPL");