blob: 5954ee1dc9538c4eb4849f07c1d28e06558782a3 [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>
Alexey Dobriyand43c36d2009-10-07 17:09:06 +040025#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/serial.h>
27#include <linux/mm.h>
28#include <linux/generic_serial.h>
29#include <linux/interrupt.h>
30#include <linux/tty_flip.h>
31#include <linux/delay.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090032#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <asm/uaccess.h>
34
35#define DEBUG
36
Linus Torvalds1da177e2005-04-16 15:20:36 -070037static int gs_debug;
38
39#ifdef DEBUG
40#define gs_dprintk(f, str...) if (gs_debug & f) printk (str)
41#else
42#define gs_dprintk(f, str...) /* nothing */
43#endif
44
Harvey Harrisonbf9d8922008-04-30 00:55:10 -070045#define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter %s\n", __func__)
46#define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit %s\n", __func__)
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48#define RS_EVENT_WRITE_WAKEUP 1
49
50module_param(gs_debug, int, 0644);
51
52
Alan Cox76b25a52008-04-30 00:54:03 -070053int gs_put_char(struct tty_struct * tty, unsigned char ch)
Linus Torvalds1da177e2005-04-16 15:20:36 -070054{
55 struct gs_port *port;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57 func_enter ();
58
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 port = tty->driver_data;
101
102 if (!port) return 0;
103
Alan Coxb5391e22008-07-16 21:55:20 +0100104 if (! (port->port.flags & ASYNC_INITIALIZED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 return 0;
106
107 /* get exclusive "write" access to this port (problem 3) */
108 /* This is not a spinlock because we can have a disk access (page
109 fault) in copy_from_user */
Ingo Molnar81861d72006-03-23 03:00:44 -0800110 mutex_lock(& port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
112 while (1) {
113
114 c = count;
115
116 /* This is safe because we "OWN" the "head". Noone else can
Ingo Molnar81861d72006-03-23 03:00:44 -0800117 change the "head": we own the port_write_mutex. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 /* Don't overrun the end of the buffer */
119 t = SERIAL_XMIT_SIZE - port->xmit_head;
120 if (t < c) c = t;
121
122 /* This is safe because the xmit_cnt can only decrease. This
123 would increase "t", so we might copy too little chars. */
124 /* Don't copy past the "head" of the buffer */
125 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt;
126 if (t < c) c = t;
127
128 /* Can't copy more? break out! */
129 if (c <= 0) break;
130
131 memcpy (port->xmit_buf + port->xmit_head, buf, c);
132
133 port -> xmit_cnt += c;
134 port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1);
135 buf += c;
136 count -= c;
137 total += c;
138 }
Ingo Molnar81861d72006-03-23 03:00:44 -0800139 mutex_unlock(& port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140
141 gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n",
Alan Coxb5391e22008-07-16 21:55:20 +0100142 (port->port.flags & GS_TX_INTEN)?"enabled": "disabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
144 if (port->xmit_cnt &&
145 !tty->stopped &&
146 !tty->hw_stopped &&
Alan Coxb5391e22008-07-16 21:55:20 +0100147 !(port->port.flags & GS_TX_INTEN)) {
148 port->port.flags |= GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 port->rd->enable_tx_interrupts (port);
150 }
151 func_exit ();
152 return total;
153}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
155
156
157int gs_write_room(struct tty_struct * tty)
158{
159 struct gs_port *port = tty->driver_data;
160 int ret;
161
162 func_enter ();
163 ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
164 if (ret < 0)
165 ret = 0;
166 func_exit ();
167 return ret;
168}
169
170
171int gs_chars_in_buffer(struct tty_struct *tty)
172{
173 struct gs_port *port = tty->driver_data;
174 func_enter ();
175
176 func_exit ();
177 return port->xmit_cnt;
178}
179
180
181static int gs_real_chars_in_buffer(struct tty_struct *tty)
182{
183 struct gs_port *port;
184 func_enter ();
185
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 port = tty->driver_data;
187
188 if (!port->rd) return 0;
189 if (!port->rd->chars_in_buffer) return 0;
190
191 func_exit ();
192 return port->xmit_cnt + port->rd->chars_in_buffer (port);
193}
194
195
196static int gs_wait_tx_flushed (void * ptr, unsigned long timeout)
197{
198 struct gs_port *port = ptr;
199 unsigned long end_jiffies;
200 int jiffies_to_transmit, charsleft = 0, rv = 0;
201 int rcib;
202
203 func_enter();
204
205 gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port);
206 if (port) {
207 gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n",
Alan Coxb5391e22008-07-16 21:55:20 +0100208 port->xmit_cnt, port->xmit_buf, port->port.tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 }
210
211 if (!port || port->xmit_cnt < 0 || !port->xmit_buf) {
212 gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n");
213 func_exit();
214 return -EINVAL; /* This is an error which we don't know how to handle. */
215 }
216
Alan Coxb5391e22008-07-16 21:55:20 +0100217 rcib = gs_real_chars_in_buffer(port->port.tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218
219 if(rcib <= 0) {
220 gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n");
221 func_exit();
222 return rv;
223 }
224 /* stop trying: now + twice the time it would normally take + seconds */
225 if (timeout == 0) timeout = MAX_SCHEDULE_TIMEOUT;
226 end_jiffies = jiffies;
227 if (timeout != MAX_SCHEDULE_TIMEOUT)
228 end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0;
229 end_jiffies += timeout;
230
231 gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n",
232 jiffies, end_jiffies, end_jiffies-jiffies);
233
234 /* the expression is actually jiffies < end_jiffies, but that won't
235 work around the wraparound. Tricky eh? */
Alan Coxb5391e22008-07-16 21:55:20 +0100236 while ((charsleft = gs_real_chars_in_buffer (port->port.tty)) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 time_after (end_jiffies, jiffies)) {
238 /* Units check:
239 chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies!
240 check! */
241
242 charsleft += 16; /* Allow 16 chars more to be transmitted ... */
243 jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0;
244 /* ^^^ Round up.... */
245 if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1;
246
247 gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies "
248 "(%d chars).\n", jiffies_to_transmit, charsleft);
249
250 msleep_interruptible(jiffies_to_msecs(jiffies_to_transmit));
251 if (signal_pending (current)) {
252 gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: ");
253 rv = -EINTR;
254 break;
255 }
256 }
257
258 gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft);
259 set_current_state (TASK_RUNNING);
260
261 func_exit();
262 return rv;
263}
264
265
266
267void gs_flush_buffer(struct tty_struct *tty)
268{
269 struct gs_port *port;
270 unsigned long flags;
271
272 func_enter ();
273
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 port = tty->driver_data;
275
276 if (!port) return;
277
278 /* XXX Would the write semaphore do? */
279 spin_lock_irqsave (&port->driver_lock, flags);
280 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
281 spin_unlock_irqrestore (&port->driver_lock, flags);
282
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 tty_wakeup(tty);
284 func_exit ();
285}
286
287
288void gs_flush_chars(struct tty_struct * tty)
289{
290 struct gs_port *port;
291
292 func_enter ();
293
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 port = tty->driver_data;
295
296 if (!port) return;
297
298 if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
299 !port->xmit_buf) {
300 func_exit ();
301 return;
302 }
303
304 /* Beats me -- REW */
Alan Coxb5391e22008-07-16 21:55:20 +0100305 port->port.flags |= GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 port->rd->enable_tx_interrupts (port);
307 func_exit ();
308}
309
310
311void gs_stop(struct tty_struct * tty)
312{
313 struct gs_port *port;
314
315 func_enter ();
316
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 port = tty->driver_data;
318
319 if (!port) return;
320
321 if (port->xmit_cnt &&
322 port->xmit_buf &&
Alan Coxb5391e22008-07-16 21:55:20 +0100323 (port->port.flags & GS_TX_INTEN) ) {
324 port->port.flags &= ~GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 port->rd->disable_tx_interrupts (port);
326 }
327 func_exit ();
328}
329
330
331void gs_start(struct tty_struct * tty)
332{
333 struct gs_port *port;
334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 port = tty->driver_data;
336
337 if (!port) return;
338
339 if (port->xmit_cnt &&
340 port->xmit_buf &&
Alan Coxb5391e22008-07-16 21:55:20 +0100341 !(port->port.flags & GS_TX_INTEN) ) {
342 port->port.flags |= GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 port->rd->enable_tx_interrupts (port);
344 }
345 func_exit ();
346}
347
348
349static void gs_shutdown_port (struct gs_port *port)
350{
351 unsigned long flags;
352
353 func_enter();
354
355 if (!port) return;
356
Alan Coxb5391e22008-07-16 21:55:20 +0100357 if (!(port->port.flags & ASYNC_INITIALIZED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358 return;
359
360 spin_lock_irqsave(&port->driver_lock, flags);
361
362 if (port->xmit_buf) {
363 free_page((unsigned long) port->xmit_buf);
364 port->xmit_buf = NULL;
365 }
366
Alan Coxb5391e22008-07-16 21:55:20 +0100367 if (port->port.tty)
368 set_bit(TTY_IO_ERROR, &port->port.tty->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
370 port->rd->shutdown_port (port);
371
Alan Coxb5391e22008-07-16 21:55:20 +0100372 port->port.flags &= ~ASYNC_INITIALIZED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 spin_unlock_irqrestore(&port->driver_lock, flags);
374
375 func_exit();
376}
377
378
379void gs_hangup(struct tty_struct *tty)
380{
Alan Cox510a3042009-01-02 13:45:36 +0000381 struct gs_port *port;
382 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
384 func_enter ();
385
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 port = tty->driver_data;
Alan Coxb5391e22008-07-16 21:55:20 +0100387 tty = port->port.tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 if (!tty)
389 return;
390
391 gs_shutdown_port (port);
Alan Cox510a3042009-01-02 13:45:36 +0000392 spin_lock_irqsave(&port->port.lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100393 port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|GS_ACTIVE);
394 port->port.tty = NULL;
395 port->port.count = 0;
Alan Cox510a3042009-01-02 13:45:36 +0000396 spin_unlock_irqrestore(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Alan Coxb5391e22008-07-16 21:55:20 +0100398 wake_up_interruptible(&port->port.open_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 func_exit ();
400}
401
402
403int gs_block_til_ready(void *port_, struct file * filp)
404{
Alan Cox31f35932009-01-02 13:45:05 +0000405 struct gs_port *gp = port_;
406 struct tty_port *port = &gp->port;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 DECLARE_WAITQUEUE(wait, current);
408 int retval;
409 int do_clocal = 0;
410 int CD;
411 struct tty_struct *tty;
412 unsigned long flags;
413
414 func_enter ();
415
416 if (!port) return 0;
417
Alan Cox31f35932009-01-02 13:45:05 +0000418 tty = port->tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n");
421 /*
422 * If the device is in the middle of being closed, then block
423 * until it's done, and then try again.
424 */
Alan Cox31f35932009-01-02 13:45:05 +0000425 if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
426 interruptible_sleep_on(&port->close_wait);
427 if (port->flags & ASYNC_HUP_NOTIFY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 return -EAGAIN;
429 else
430 return -ERESTARTSYS;
431 }
432
433 gs_dprintk (GS_DEBUG_BTR, "after hung up\n");
434
435 /*
436 * If non-blocking mode is set, or the port is not enabled,
437 * then make the check up front and then exit.
438 */
439 if ((filp->f_flags & O_NONBLOCK) ||
440 (tty->flags & (1 << TTY_IO_ERROR))) {
Alan Cox31f35932009-01-02 13:45:05 +0000441 port->flags |= ASYNC_NORMAL_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 return 0;
443 }
444
445 gs_dprintk (GS_DEBUG_BTR, "after nonblock\n");
446
447 if (C_CLOCAL(tty))
448 do_clocal = 1;
449
450 /*
451 * Block waiting for the carrier detect and the line to become
452 * free (i.e., not in use by the callout). While we are in
Alan Cox31f35932009-01-02 13:45:05 +0000453 * this loop, port->count is dropped by one, so that
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 * rs_close() knows when to free things. We restore it upon
455 * exit, either normal or abnormal.
456 */
457 retval = 0;
458
Alan Cox31f35932009-01-02 13:45:05 +0000459 add_wait_queue(&port->open_wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460
461 gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n");
Alan Cox510a3042009-01-02 13:45:36 +0000462 spin_lock_irqsave(&port->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 if (!tty_hung_up_p(filp)) {
Alan Cox31f35932009-01-02 13:45:05 +0000464 port->count--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 }
Alan Cox31f35932009-01-02 13:45:05 +0000466 port->blocked_open++;
Alan Cox510a3042009-01-02 13:45:36 +0000467 spin_unlock_irqrestore(&port->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 while (1) {
Alan Cox31f35932009-01-02 13:45:05 +0000469 CD = tty_port_carrier_raised(port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
471 set_current_state (TASK_INTERRUPTIBLE);
472 if (tty_hung_up_p(filp) ||
Alan Cox31f35932009-01-02 13:45:05 +0000473 !(port->flags & ASYNC_INITIALIZED)) {
474 if (port->flags & ASYNC_HUP_NOTIFY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 retval = -EAGAIN;
476 else
477 retval = -ERESTARTSYS;
478 break;
479 }
Alan Cox31f35932009-01-02 13:45:05 +0000480 if (!(port->flags & ASYNC_CLOSING) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 (do_clocal || CD))
482 break;
483 gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n",
484 (int)signal_pending (current), *(long*)(&current->blocked));
485 if (signal_pending(current)) {
486 retval = -ERESTARTSYS;
487 break;
488 }
489 schedule();
490 }
491 gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
Alan Cox31f35932009-01-02 13:45:05 +0000492 port->blocked_open);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 set_current_state (TASK_RUNNING);
Alan Cox31f35932009-01-02 13:45:05 +0000494 remove_wait_queue(&port->open_wait, &wait);
Alan Cox510a3042009-01-02 13:45:36 +0000495
496 spin_lock_irqsave(&port->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 if (!tty_hung_up_p(filp)) {
Alan Cox31f35932009-01-02 13:45:05 +0000498 port->count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 }
Alan Cox31f35932009-01-02 13:45:05 +0000500 port->blocked_open--;
Alan Cox510a3042009-01-02 13:45:36 +0000501 if (retval == 0)
502 port->flags |= ASYNC_NORMAL_ACTIVE;
503 spin_unlock_irqrestore(&port->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 func_exit ();
Alan Cox510a3042009-01-02 13:45:36 +0000505 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506}
507
508
509void gs_close(struct tty_struct * tty, struct file * filp)
510{
511 unsigned long flags;
512 struct gs_port *port;
513
514 func_enter ();
515
Alan Coxc9f19e92009-01-02 13:47:26 +0000516 port = tty->driver_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517
518 if (!port) return;
519
Alan Coxb5391e22008-07-16 21:55:20 +0100520 if (!port->port.tty) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 /* This seems to happen when this is called from vhangup. */
Alan Coxb5391e22008-07-16 21:55:20 +0100522 gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->port.tty is NULL\n");
523 port->port.tty = tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 }
525
Alan Cox510a3042009-01-02 13:45:36 +0000526 spin_lock_irqsave(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527
528 if (tty_hung_up_p(filp)) {
Alan Cox510a3042009-01-02 13:45:36 +0000529 spin_unlock_irqrestore(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 if (port->rd->hungup)
531 port->rd->hungup (port);
532 func_exit ();
533 return;
534 }
535
Alan Coxb5391e22008-07-16 21:55:20 +0100536 if ((tty->count == 1) && (port->port.count != 1)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 printk(KERN_ERR "gs: gs_close port %p: bad port count;"
Alan Coxb5391e22008-07-16 21:55:20 +0100538 " tty->count is 1, port count is %d\n", port, port->port.count);
539 port->port.count = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 }
Alan Coxb5391e22008-07-16 21:55:20 +0100541 if (--port->port.count < 0) {
542 printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->port.count);
543 port->port.count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 }
545
Alan Coxb5391e22008-07-16 21:55:20 +0100546 if (port->port.count) {
547 gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->port.count);
Alan Cox510a3042009-01-02 13:45:36 +0000548 spin_unlock_irqrestore(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 func_exit ();
550 return;
551 }
Alan Coxb5391e22008-07-16 21:55:20 +0100552 port->port.flags |= ASYNC_CLOSING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553
554 /*
555 * Now we wait for the transmit buffer to clear; and we notify
556 * the line discipline to only process XON/XOFF characters.
557 */
558 tty->closing = 1;
559 /* if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
560 tty_wait_until_sent(tty, port->closing_wait); */
561
562 /*
563 * At this point we stop accepting input. To do this, we
564 * disable the receive line status interrupts, and tell the
565 * interrupt driver to stop checking the data ready bit in the
566 * line status register.
567 */
568
Alan Cox510a3042009-01-02 13:45:36 +0000569 spin_lock_irqsave(&port->driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 port->rd->disable_rx_interrupts (port);
571 spin_unlock_irqrestore(&port->driver_lock, flags);
Alan Cox510a3042009-01-02 13:45:36 +0000572 spin_unlock_irqrestore(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
574 /* close has no way of returning "EINTR", so discard return value */
575 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
576 gs_wait_tx_flushed (port, port->closing_wait);
577
Alan Coxb5391e22008-07-16 21:55:20 +0100578 port->port.flags &= ~GS_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579
Alan Cox978e5952008-04-30 00:53:59 -0700580 gs_flush_buffer(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581
582 tty_ldisc_flush(tty);
583 tty->closing = 0;
584
Alan Cox510a3042009-01-02 13:45:36 +0000585 spin_lock_irqsave(&port->driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 port->event = 0;
587 port->rd->close (port);
588 port->rd->shutdown_port (port);
Alan Cox510a3042009-01-02 13:45:36 +0000589 spin_unlock_irqrestore(&port->driver_lock, flags);
590
591 spin_lock_irqsave(&port->port.lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100592 port->port.tty = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593
Alan Coxb5391e22008-07-16 21:55:20 +0100594 if (port->port.blocked_open) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 if (port->close_delay) {
Alan Cox510a3042009-01-02 13:45:36 +0000596 spin_unlock_irqrestore(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 msleep_interruptible(jiffies_to_msecs(port->close_delay));
Alan Cox510a3042009-01-02 13:45:36 +0000598 spin_lock_irqsave(&port->port.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 }
Alan Coxb5391e22008-07-16 21:55:20 +0100600 wake_up_interruptible(&port->port.open_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 }
Alan Coxb5391e22008-07-16 21:55:20 +0100602 port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED);
Alan Cox510a3042009-01-02 13:45:36 +0000603 spin_unlock_irqrestore(&port->port.lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100604 wake_up_interruptible(&port->port.close_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605
606 func_exit ();
607}
608
609
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610void gs_set_termios (struct tty_struct * tty,
Alan Cox606d0992006-12-08 02:38:45 -0800611 struct ktermios * old_termios)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612{
613 struct gs_port *port;
614 int baudrate, tmp, rv;
Alan Cox606d0992006-12-08 02:38:45 -0800615 struct ktermios *tiosp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616
617 func_enter();
618
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 port = tty->driver_data;
620
621 if (!port) return;
Alan Coxb5391e22008-07-16 21:55:20 +0100622 if (!port->port.tty) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 /* This seems to happen when this is called after gs_close. */
Alan Coxb5391e22008-07-16 21:55:20 +0100624 gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->port.tty is NULL\n");
625 port->port.tty = tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626 }
627
628
629 tiosp = tty->termios;
630
631 if (gs_debug & GS_DEBUG_TERMIOS) {
632 gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp);
633 }
634
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) {
636 if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n");
637 if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n");
638 if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n");
639 if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n");
640 if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n");
641 if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n");
642 }
643
Alan Coxd720bc42006-09-29 02:01:38 -0700644 baudrate = tty_get_baud_rate(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 if ((tiosp->c_cflag & CBAUD) == B38400) {
Alan Coxb5391e22008-07-16 21:55:20 +0100647 if ( (port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 baudrate = 57600;
Alan Coxb5391e22008-07-16 21:55:20 +0100649 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 baudrate = 115200;
Alan Coxb5391e22008-07-16 21:55:20 +0100651 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 baudrate = 230400;
Alan Coxb5391e22008-07-16 21:55:20 +0100653 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 baudrate = 460800;
Alan Coxb5391e22008-07-16 21:55:20 +0100655 else if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 baudrate = (port->baud_base / port->custom_divisor);
657 }
658
659 /* I recommend using THIS instead of the mess in termios (and
660 duplicating the above code). Next we should create a clean
661 interface towards this variable. If your card supports arbitrary
662 baud rates, (e.g. CD1400 or 16550 based cards) then everything
663 will be very easy..... */
664 port->baud = baudrate;
665
666 /* Two timer ticks seems enough to wakeup something like SLIP driver */
667 /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */
668 tmp = (baudrate / 10 / HZ) * 2;
669
670 if (tmp < 0) tmp = 0;
671 if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1;
672
673 port->wakeup_chars = tmp;
674
675 /* We should really wait for the characters to be all sent before
676 changing the settings. -- CAL */
677 rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT);
678 if (rv < 0) return /* rv */;
679
680 rv = port->rd->set_real_termios(port);
681 if (rv < 0) return /* rv */;
682
683 if ((!old_termios ||
684 (old_termios->c_cflag & CRTSCTS)) &&
685 !( tiosp->c_cflag & CRTSCTS)) {
686 tty->stopped = 0;
687 gs_start(tty);
688 }
689
690#ifdef tytso_patch_94Nov25_1726
691 /* This "makes sense", Why is it commented out? */
692
693 if (!(old_termios->c_cflag & CLOCAL) &&
694 (tty->termios->c_cflag & CLOCAL))
695 wake_up_interruptible(&port->gs.open_wait);
696#endif
697
698 func_exit();
699 return /* 0 */;
700}
701
702
703
704/* Must be called with interrupts enabled */
705int gs_init_port(struct gs_port *port)
706{
707 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708
709 func_enter ();
710
Alan Coxb5391e22008-07-16 21:55:20 +0100711 if (port->port.flags & ASYNC_INITIALIZED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712 func_exit ();
713 return 0;
714 }
715 if (!port->xmit_buf) {
716 /* We may sleep in get_zeroed_page() */
717 unsigned long tmp;
718
719 tmp = get_zeroed_page(GFP_KERNEL);
720 spin_lock_irqsave (&port->driver_lock, flags);
721 if (port->xmit_buf)
722 free_page (tmp);
723 else
724 port->xmit_buf = (unsigned char *) tmp;
725 spin_unlock_irqrestore(&port->driver_lock, flags);
726 if (!port->xmit_buf) {
727 func_exit ();
728 return -ENOMEM;
729 }
730 }
731
732 spin_lock_irqsave (&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100733 if (port->port.tty)
734 clear_bit(TTY_IO_ERROR, &port->port.tty->flags);
Ingo Molnar81861d72006-03-23 03:00:44 -0800735 mutex_init(&port->port_write_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
737 spin_unlock_irqrestore(&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100738 gs_set_termios(port->port.tty, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 spin_lock_irqsave (&port->driver_lock, flags);
Alan Coxb5391e22008-07-16 21:55:20 +0100740 port->port.flags |= ASYNC_INITIALIZED;
741 port->port.flags &= ~GS_TX_INTEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
743 spin_unlock_irqrestore(&port->driver_lock, flags);
744 func_exit ();
745 return 0;
746}
747
748
749int gs_setserial(struct gs_port *port, struct serial_struct __user *sp)
750{
751 struct serial_struct sio;
752
753 if (copy_from_user(&sio, sp, sizeof(struct serial_struct)))
754 return(-EFAULT);
755
756 if (!capable(CAP_SYS_ADMIN)) {
757 if ((sio.baud_base != port->baud_base) ||
758 (sio.close_delay != port->close_delay) ||
759 ((sio.flags & ~ASYNC_USR_MASK) !=
Alan Coxb5391e22008-07-16 21:55:20 +0100760 (port->port.flags & ~ASYNC_USR_MASK)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 return(-EPERM);
762 }
763
Alan Coxb5391e22008-07-16 21:55:20 +0100764 port->port.flags = (port->port.flags & ~ASYNC_USR_MASK) |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 (sio.flags & ASYNC_USR_MASK);
766
767 port->baud_base = sio.baud_base;
768 port->close_delay = sio.close_delay;
769 port->closing_wait = sio.closing_wait;
770 port->custom_divisor = sio.custom_divisor;
771
Alan Coxb5391e22008-07-16 21:55:20 +0100772 gs_set_termios (port->port.tty, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773
774 return 0;
775}
776
777
778/*****************************************************************************/
779
780/*
781 * Generate the serial struct info.
782 */
783
784int gs_getserial(struct gs_port *port, struct serial_struct __user *sp)
785{
786 struct serial_struct sio;
787
788 memset(&sio, 0, sizeof(struct serial_struct));
Alan Coxb5391e22008-07-16 21:55:20 +0100789 sio.flags = port->port.flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 sio.baud_base = port->baud_base;
791 sio.close_delay = port->close_delay;
792 sio.closing_wait = port->closing_wait;
793 sio.custom_divisor = port->custom_divisor;
794 sio.hub6 = 0;
795
796 /* If you want you can override these. */
797 sio.type = PORT_UNKNOWN;
798 sio.xmit_fifo_size = -1;
799 sio.line = -1;
800 sio.port = -1;
801 sio.irq = -1;
802
803 if (port->rd->getserial)
804 port->rd->getserial (port, &sio);
805
806 if (copy_to_user(sp, &sio, sizeof(struct serial_struct)))
807 return -EFAULT;
808 return 0;
809
810}
811
812
813void gs_got_break(struct gs_port *port)
814{
815 func_enter ();
816
Alan Coxb5391e22008-07-16 21:55:20 +0100817 tty_insert_flip_char(port->port.tty, 0, TTY_BREAK);
818 tty_schedule_flip(port->port.tty);
819 if (port->port.flags & ASYNC_SAK) {
820 do_SAK (port->port.tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821 }
822
823 func_exit ();
824}
825
826
827EXPORT_SYMBOL(gs_put_char);
828EXPORT_SYMBOL(gs_write);
829EXPORT_SYMBOL(gs_write_room);
830EXPORT_SYMBOL(gs_chars_in_buffer);
831EXPORT_SYMBOL(gs_flush_buffer);
832EXPORT_SYMBOL(gs_flush_chars);
833EXPORT_SYMBOL(gs_stop);
834EXPORT_SYMBOL(gs_start);
835EXPORT_SYMBOL(gs_hangup);
836EXPORT_SYMBOL(gs_block_til_ready);
837EXPORT_SYMBOL(gs_close);
838EXPORT_SYMBOL(gs_set_termios);
839EXPORT_SYMBOL(gs_init_port);
840EXPORT_SYMBOL(gs_setserial);
841EXPORT_SYMBOL(gs_getserial);
842EXPORT_SYMBOL(gs_got_break);
843
844MODULE_LICENSE("GPL");