Loading...
1/************************************************************************
2 * Copyright 2003 Digi International (www.digi.com)
3 *
4 * Copyright (C) 2004 IBM Corporation. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2, or (at your option)
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
13 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
14 * PURPOSE. See the GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 * Temple Place - Suite 330, Boston,
19 * MA 02111-1307, USA.
20 *
21 * Contact Information:
22 * Scott H Kilau <Scott_Kilau@digi.com>
23 * Ananda Venkatarman <mansarov@us.ibm.com>
24 * Modifications:
25 * 01/19/06: changed jsm_input routine to use the dynamically allocated
26 * tty_buffer changes. Contributors: Scott Kilau and Ananda V.
27 ***********************************************************************/
28#include <linux/tty.h>
29#include <linux/tty_flip.h>
30#include <linux/serial_reg.h>
31#include <linux/delay.h> /* For udelay */
32#include <linux/pci.h>
33#include <linux/slab.h>
34
35#include "jsm.h"
36
37static DECLARE_BITMAP(linemap, MAXLINES);
38
39static void jsm_carrier(struct jsm_channel *ch);
40
41static inline int jsm_get_mstat(struct jsm_channel *ch)
42{
43 unsigned char mstat;
44 unsigned result;
45
46 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "start\n");
47
48 mstat = (ch->ch_mostat | ch->ch_mistat);
49
50 result = 0;
51
52 if (mstat & UART_MCR_DTR)
53 result |= TIOCM_DTR;
54 if (mstat & UART_MCR_RTS)
55 result |= TIOCM_RTS;
56 if (mstat & UART_MSR_CTS)
57 result |= TIOCM_CTS;
58 if (mstat & UART_MSR_DSR)
59 result |= TIOCM_DSR;
60 if (mstat & UART_MSR_RI)
61 result |= TIOCM_RI;
62 if (mstat & UART_MSR_DCD)
63 result |= TIOCM_CD;
64
65 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n");
66 return result;
67}
68
69static unsigned int jsm_tty_tx_empty(struct uart_port *port)
70{
71 return TIOCSER_TEMT;
72}
73
74/*
75 * Return modem signals to ld.
76 */
77static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
78{
79 int result;
80 struct jsm_channel *channel = (struct jsm_channel *)port;
81
82 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
83
84 result = jsm_get_mstat(channel);
85
86 if (result < 0)
87 return -ENXIO;
88
89 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
90
91 return result;
92}
93
94/*
95 * jsm_set_modem_info()
96 *
97 * Set modem signals, called by ld.
98 */
99static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
100{
101 struct jsm_channel *channel = (struct jsm_channel *)port;
102
103 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
104
105 if (mctrl & TIOCM_RTS)
106 channel->ch_mostat |= UART_MCR_RTS;
107 else
108 channel->ch_mostat &= ~UART_MCR_RTS;
109
110 if (mctrl & TIOCM_DTR)
111 channel->ch_mostat |= UART_MCR_DTR;
112 else
113 channel->ch_mostat &= ~UART_MCR_DTR;
114
115 channel->ch_bd->bd_ops->assert_modem_signals(channel);
116
117 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
118 udelay(10);
119}
120
121static void jsm_tty_start_tx(struct uart_port *port)
122{
123 struct jsm_channel *channel = (struct jsm_channel *)port;
124
125 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
126
127 channel->ch_flags &= ~(CH_STOP);
128 jsm_tty_write(port);
129
130 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
131}
132
133static void jsm_tty_stop_tx(struct uart_port *port)
134{
135 struct jsm_channel *channel = (struct jsm_channel *)port;
136
137 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
138
139 channel->ch_flags |= (CH_STOP);
140
141 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
142}
143
144static void jsm_tty_send_xchar(struct uart_port *port, char ch)
145{
146 unsigned long lock_flags;
147 struct jsm_channel *channel = (struct jsm_channel *)port;
148 struct ktermios *termios;
149
150 spin_lock_irqsave(&port->lock, lock_flags);
151 termios = port->state->port.tty->termios;
152 if (ch == termios->c_cc[VSTART])
153 channel->ch_bd->bd_ops->send_start_character(channel);
154
155 if (ch == termios->c_cc[VSTOP])
156 channel->ch_bd->bd_ops->send_stop_character(channel);
157 spin_unlock_irqrestore(&port->lock, lock_flags);
158}
159
160static void jsm_tty_stop_rx(struct uart_port *port)
161{
162 struct jsm_channel *channel = (struct jsm_channel *)port;
163
164 channel->ch_bd->bd_ops->disable_receiver(channel);
165}
166
167static void jsm_tty_enable_ms(struct uart_port *port)
168{
169 /* Nothing needed */
170}
171
172static void jsm_tty_break(struct uart_port *port, int break_state)
173{
174 unsigned long lock_flags;
175 struct jsm_channel *channel = (struct jsm_channel *)port;
176
177 spin_lock_irqsave(&port->lock, lock_flags);
178 if (break_state == -1)
179 channel->ch_bd->bd_ops->send_break(channel);
180 else
181 channel->ch_bd->bd_ops->clear_break(channel, 0);
182
183 spin_unlock_irqrestore(&port->lock, lock_flags);
184}
185
186static int jsm_tty_open(struct uart_port *port)
187{
188 struct jsm_board *brd;
189 struct jsm_channel *channel = (struct jsm_channel *)port;
190 struct ktermios *termios;
191
192 /* Get board pointer from our array of majors we have allocated */
193 brd = channel->ch_bd;
194
195 /*
196 * Allocate channel buffers for read/write/error.
197 * Set flag, so we don't get trounced on.
198 */
199 channel->ch_flags |= (CH_OPENING);
200
201 /* Drop locks, as malloc with GFP_KERNEL can sleep */
202
203 if (!channel->ch_rqueue) {
204 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
205 if (!channel->ch_rqueue) {
206 jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
207 "unable to allocate read queue buf");
208 return -ENOMEM;
209 }
210 }
211 if (!channel->ch_equeue) {
212 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
213 if (!channel->ch_equeue) {
214 jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
215 "unable to allocate error queue buf");
216 return -ENOMEM;
217 }
218 }
219 if (!channel->ch_wqueue) {
220 channel->ch_wqueue = kzalloc(WQUEUESIZE, GFP_KERNEL);
221 if (!channel->ch_wqueue) {
222 jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
223 "unable to allocate write queue buf");
224 return -ENOMEM;
225 }
226 }
227
228 channel->ch_flags &= ~(CH_OPENING);
229 /*
230 * Initialize if neither terminal is open.
231 */
232 jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev,
233 "jsm_open: initializing channel in open...\n");
234
235 /*
236 * Flush input queues.
237 */
238 channel->ch_r_head = channel->ch_r_tail = 0;
239 channel->ch_e_head = channel->ch_e_tail = 0;
240 channel->ch_w_head = channel->ch_w_tail = 0;
241
242 brd->bd_ops->flush_uart_write(channel);
243 brd->bd_ops->flush_uart_read(channel);
244
245 channel->ch_flags = 0;
246 channel->ch_cached_lsr = 0;
247 channel->ch_stops_sent = 0;
248
249 termios = port->state->port.tty->termios;
250 channel->ch_c_cflag = termios->c_cflag;
251 channel->ch_c_iflag = termios->c_iflag;
252 channel->ch_c_oflag = termios->c_oflag;
253 channel->ch_c_lflag = termios->c_lflag;
254 channel->ch_startc = termios->c_cc[VSTART];
255 channel->ch_stopc = termios->c_cc[VSTOP];
256
257 /* Tell UART to init itself */
258 brd->bd_ops->uart_init(channel);
259
260 /*
261 * Run param in case we changed anything
262 */
263 brd->bd_ops->param(channel);
264
265 jsm_carrier(channel);
266
267 channel->ch_open_count++;
268
269 jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev, "finish\n");
270 return 0;
271}
272
273static void jsm_tty_close(struct uart_port *port)
274{
275 struct jsm_board *bd;
276 struct ktermios *ts;
277 struct jsm_channel *channel = (struct jsm_channel *)port;
278
279 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "start\n");
280
281 bd = channel->ch_bd;
282 ts = port->state->port.tty->termios;
283
284 channel->ch_flags &= ~(CH_STOPI);
285
286 channel->ch_open_count--;
287
288 /*
289 * If we have HUPCL set, lower DTR and RTS
290 */
291 if (channel->ch_c_cflag & HUPCL) {
292 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev,
293 "Close. HUPCL set, dropping DTR/RTS\n");
294
295 /* Drop RTS/DTR */
296 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
297 bd->bd_ops->assert_modem_signals(channel);
298 }
299
300 /* Turn off UART interrupts for this port */
301 channel->ch_bd->bd_ops->uart_off(channel);
302
303 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "finish\n");
304}
305
306static void jsm_tty_set_termios(struct uart_port *port,
307 struct ktermios *termios,
308 struct ktermios *old_termios)
309{
310 unsigned long lock_flags;
311 struct jsm_channel *channel = (struct jsm_channel *)port;
312
313 spin_lock_irqsave(&port->lock, lock_flags);
314 channel->ch_c_cflag = termios->c_cflag;
315 channel->ch_c_iflag = termios->c_iflag;
316 channel->ch_c_oflag = termios->c_oflag;
317 channel->ch_c_lflag = termios->c_lflag;
318 channel->ch_startc = termios->c_cc[VSTART];
319 channel->ch_stopc = termios->c_cc[VSTOP];
320
321 channel->ch_bd->bd_ops->param(channel);
322 jsm_carrier(channel);
323 spin_unlock_irqrestore(&port->lock, lock_flags);
324}
325
326static const char *jsm_tty_type(struct uart_port *port)
327{
328 return "jsm";
329}
330
331static void jsm_tty_release_port(struct uart_port *port)
332{
333}
334
335static int jsm_tty_request_port(struct uart_port *port)
336{
337 return 0;
338}
339
340static void jsm_config_port(struct uart_port *port, int flags)
341{
342 port->type = PORT_JSM;
343}
344
345static struct uart_ops jsm_ops = {
346 .tx_empty = jsm_tty_tx_empty,
347 .set_mctrl = jsm_tty_set_mctrl,
348 .get_mctrl = jsm_tty_get_mctrl,
349 .stop_tx = jsm_tty_stop_tx,
350 .start_tx = jsm_tty_start_tx,
351 .send_xchar = jsm_tty_send_xchar,
352 .stop_rx = jsm_tty_stop_rx,
353 .enable_ms = jsm_tty_enable_ms,
354 .break_ctl = jsm_tty_break,
355 .startup = jsm_tty_open,
356 .shutdown = jsm_tty_close,
357 .set_termios = jsm_tty_set_termios,
358 .type = jsm_tty_type,
359 .release_port = jsm_tty_release_port,
360 .request_port = jsm_tty_request_port,
361 .config_port = jsm_config_port,
362};
363
364/*
365 * jsm_tty_init()
366 *
367 * Init the tty subsystem. Called once per board after board has been
368 * downloaded and init'ed.
369 */
370int __devinit jsm_tty_init(struct jsm_board *brd)
371{
372 int i;
373 void __iomem *vaddr;
374 struct jsm_channel *ch;
375
376 if (!brd)
377 return -ENXIO;
378
379 jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
380
381 /*
382 * Initialize board structure elements.
383 */
384
385 brd->nasync = brd->maxports;
386
387 /*
388 * Allocate channel memory that might not have been allocated
389 * when the driver was first loaded.
390 */
391 for (i = 0; i < brd->nasync; i++) {
392 if (!brd->channels[i]) {
393
394 /*
395 * Okay to malloc with GFP_KERNEL, we are not at
396 * interrupt context, and there are no locks held.
397 */
398 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
399 if (!brd->channels[i]) {
400 jsm_printk(CORE, ERR, &brd->pci_dev,
401 "%s:%d Unable to allocate memory for channel struct\n",
402 __FILE__, __LINE__);
403 }
404 }
405 }
406
407 ch = brd->channels[0];
408 vaddr = brd->re_map_membase;
409
410 /* Set up channel variables */
411 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
412
413 if (!brd->channels[i])
414 continue;
415
416 spin_lock_init(&ch->ch_lock);
417
418 if (brd->bd_uart_offset == 0x200)
419 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i);
420
421 ch->ch_bd = brd;
422 ch->ch_portnum = i;
423
424 /* .25 second delay */
425 ch->ch_close_delay = 250;
426
427 init_waitqueue_head(&ch->ch_flags_wait);
428 }
429
430 jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
431 return 0;
432}
433
434int jsm_uart_port_init(struct jsm_board *brd)
435{
436 int i, rc;
437 unsigned int line;
438 struct jsm_channel *ch;
439
440 if (!brd)
441 return -ENXIO;
442
443 jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
444
445 /*
446 * Initialize board structure elements.
447 */
448
449 brd->nasync = brd->maxports;
450
451 /* Set up channel variables */
452 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
453
454 if (!brd->channels[i])
455 continue;
456
457 brd->channels[i]->uart_port.irq = brd->irq;
458 brd->channels[i]->uart_port.uartclk = 14745600;
459 brd->channels[i]->uart_port.type = PORT_JSM;
460 brd->channels[i]->uart_port.iotype = UPIO_MEM;
461 brd->channels[i]->uart_port.membase = brd->re_map_membase;
462 brd->channels[i]->uart_port.fifosize = 16;
463 brd->channels[i]->uart_port.ops = &jsm_ops;
464 line = find_first_zero_bit(linemap, MAXLINES);
465 if (line >= MAXLINES) {
466 printk(KERN_INFO "jsm: linemap is full, added device failed\n");
467 continue;
468 } else
469 set_bit(line, linemap);
470 brd->channels[i]->uart_port.line = line;
471 rc = uart_add_one_port (&jsm_uart_driver, &brd->channels[i]->uart_port);
472 if (rc){
473 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
474 return rc;
475 }
476 else
477 printk(KERN_INFO "jsm: Port %d added\n", i);
478 }
479
480 jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
481 return 0;
482}
483
484int jsm_remove_uart_port(struct jsm_board *brd)
485{
486 int i;
487 struct jsm_channel *ch;
488
489 if (!brd)
490 return -ENXIO;
491
492 jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
493
494 /*
495 * Initialize board structure elements.
496 */
497
498 brd->nasync = brd->maxports;
499
500 /* Set up channel variables */
501 for (i = 0; i < brd->nasync; i++) {
502
503 if (!brd->channels[i])
504 continue;
505
506 ch = brd->channels[i];
507
508 clear_bit(ch->uart_port.line, linemap);
509 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
510 }
511
512 jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
513 return 0;
514}
515
516void jsm_input(struct jsm_channel *ch)
517{
518 struct jsm_board *bd;
519 struct tty_struct *tp;
520 u32 rmask;
521 u16 head;
522 u16 tail;
523 int data_len;
524 unsigned long lock_flags;
525 int len = 0;
526 int n = 0;
527 int s = 0;
528 int i = 0;
529
530 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n");
531
532 if (!ch)
533 return;
534
535 tp = ch->uart_port.state->port.tty;
536
537 bd = ch->ch_bd;
538 if(!bd)
539 return;
540
541 spin_lock_irqsave(&ch->ch_lock, lock_flags);
542
543 /*
544 *Figure the number of characters in the buffer.
545 *Exit immediately if none.
546 */
547
548 rmask = RQUEUEMASK;
549
550 head = ch->ch_r_head & rmask;
551 tail = ch->ch_r_tail & rmask;
552
553 data_len = (head - tail) & rmask;
554 if (data_len == 0) {
555 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
556 return;
557 }
558
559 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n");
560
561 /*
562 *If the device is not open, or CREAD is off, flush
563 *input data and return immediately.
564 */
565 if (!tp ||
566 !(tp->termios->c_cflag & CREAD) ) {
567
568 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
569 "input. dropping %d bytes on port %d...\n", data_len, ch->ch_portnum);
570 ch->ch_r_head = tail;
571
572 /* Force queue flow control to be released, if needed */
573 jsm_check_queue_flow_control(ch);
574
575 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
576 return;
577 }
578
579 /*
580 * If we are throttled, simply don't read any data.
581 */
582 if (ch->ch_flags & CH_STOPI) {
583 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
584 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
585 "Port %d throttled, not reading any data. head: %x tail: %x\n",
586 ch->ch_portnum, head, tail);
587 return;
588 }
589
590 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start 2\n");
591
592 if (data_len <= 0) {
593 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
594 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "jsm_input 1\n");
595 return;
596 }
597
598 len = tty_buffer_request_room(tp, data_len);
599 n = len;
600
601 /*
602 * n now contains the most amount of data we can copy,
603 * bounded either by the flip buffer size or the amount
604 * of data the card actually has pending...
605 */
606 while (n) {
607 s = ((head >= tail) ? head : RQUEUESIZE) - tail;
608 s = min(s, n);
609
610 if (s <= 0)
611 break;
612
613 /*
614 * If conditions are such that ld needs to see all
615 * UART errors, we will have to walk each character
616 * and error byte and send them to the buffer one at
617 * a time.
618 */
619
620 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
621 for (i = 0; i < s; i++) {
622 /*
623 * Give the Linux ld the flags in the
624 * format it likes.
625 */
626 if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
627 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_BREAK);
628 else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
629 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_PARITY);
630 else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
631 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_FRAME);
632 else
633 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
634 }
635 } else {
636 tty_insert_flip_string(tp, ch->ch_rqueue + tail, s) ;
637 }
638 tail += s;
639 n -= s;
640 /* Flip queue if needed */
641 tail &= rmask;
642 }
643
644 ch->ch_r_tail = tail & rmask;
645 ch->ch_e_tail = tail & rmask;
646 jsm_check_queue_flow_control(ch);
647 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
648
649 /* Tell the tty layer its okay to "eat" the data now */
650 tty_flip_buffer_push(tp);
651
652 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n");
653}
654
655static void jsm_carrier(struct jsm_channel *ch)
656{
657 struct jsm_board *bd;
658
659 int virt_carrier = 0;
660 int phys_carrier = 0;
661
662 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, "start\n");
663 if (!ch)
664 return;
665
666 bd = ch->ch_bd;
667
668 if (!bd)
669 return;
670
671 if (ch->ch_mistat & UART_MSR_DCD) {
672 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
673 "mistat: %x D_CD: %x\n", ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
674 phys_carrier = 1;
675 }
676
677 if (ch->ch_c_cflag & CLOCAL)
678 virt_carrier = 1;
679
680 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
681 "DCD: physical: %d virt: %d\n", phys_carrier, virt_carrier);
682
683 /*
684 * Test for a VIRTUAL carrier transition to HIGH.
685 */
686 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
687
688 /*
689 * When carrier rises, wake any threads waiting
690 * for carrier in the open routine.
691 */
692
693 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
694 "carrier: virt DCD rose\n");
695
696 if (waitqueue_active(&(ch->ch_flags_wait)))
697 wake_up_interruptible(&ch->ch_flags_wait);
698 }
699
700 /*
701 * Test for a PHYSICAL carrier transition to HIGH.
702 */
703 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
704
705 /*
706 * When carrier rises, wake any threads waiting
707 * for carrier in the open routine.
708 */
709
710 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
711 "carrier: physical DCD rose\n");
712
713 if (waitqueue_active(&(ch->ch_flags_wait)))
714 wake_up_interruptible(&ch->ch_flags_wait);
715 }
716
717 /*
718 * Test for a PHYSICAL transition to low, so long as we aren't
719 * currently ignoring physical transitions (which is what "virtual
720 * carrier" indicates).
721 *
722 * The transition of the virtual carrier to low really doesn't
723 * matter... it really only means "ignore carrier state", not
724 * "make pretend that carrier is there".
725 */
726 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
727 && (phys_carrier == 0)) {
728 /*
729 * When carrier drops:
730 *
731 * Drop carrier on all open units.
732 *
733 * Flush queues, waking up any task waiting in the
734 * line discipline.
735 *
736 * Send a hangup to the control terminal.
737 *
738 * Enable all select calls.
739 */
740 if (waitqueue_active(&(ch->ch_flags_wait)))
741 wake_up_interruptible(&ch->ch_flags_wait);
742 }
743
744 /*
745 * Make sure that our cached values reflect the current reality.
746 */
747 if (virt_carrier == 1)
748 ch->ch_flags |= CH_FCAR;
749 else
750 ch->ch_flags &= ~CH_FCAR;
751
752 if (phys_carrier == 1)
753 ch->ch_flags |= CH_CD;
754 else
755 ch->ch_flags &= ~CH_CD;
756}
757
758
759void jsm_check_queue_flow_control(struct jsm_channel *ch)
760{
761 struct board_ops *bd_ops = ch->ch_bd->bd_ops;
762 int qleft;
763
764 /* Store how much space we have left in the queue */
765 if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
766 qleft += RQUEUEMASK + 1;
767
768 /*
769 * Check to see if we should enforce flow control on our queue because
770 * the ld (or user) isn't reading data out of our queue fast enuf.
771 *
772 * NOTE: This is done based on what the current flow control of the
773 * port is set for.
774 *
775 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
776 * This will cause the UART's FIFO to back up, and force
777 * the RTS signal to be dropped.
778 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
779 * the other side, in hopes it will stop sending data to us.
780 * 3) NONE - Nothing we can do. We will simply drop any extra data
781 * that gets sent into us when the queue fills up.
782 */
783 if (qleft < 256) {
784 /* HWFLOW */
785 if (ch->ch_c_cflag & CRTSCTS) {
786 if(!(ch->ch_flags & CH_RECEIVER_OFF)) {
787 bd_ops->disable_receiver(ch);
788 ch->ch_flags |= (CH_RECEIVER_OFF);
789 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
790 "Internal queue hit hilevel mark (%d)! Turning off interrupts.\n",
791 qleft);
792 }
793 }
794 /* SWFLOW */
795 else if (ch->ch_c_iflag & IXOFF) {
796 if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
797 bd_ops->send_stop_character(ch);
798 ch->ch_stops_sent++;
799 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
800 "Sending stop char! Times sent: %x\n", ch->ch_stops_sent);
801 }
802 }
803 }
804
805 /*
806 * Check to see if we should unenforce flow control because
807 * ld (or user) finally read enuf data out of our queue.
808 *
809 * NOTE: This is done based on what the current flow control of the
810 * port is set for.
811 *
812 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
813 * This will cause the UART's FIFO to raise RTS back up,
814 * which will allow the other side to start sending data again.
815 * 2) SWFLOW (IXOFF) - Send a start character to
816 * the other side, so it will start sending data to us again.
817 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
818 * other side, we don't need to do anything now.
819 */
820 if (qleft > (RQUEUESIZE / 2)) {
821 /* HWFLOW */
822 if (ch->ch_c_cflag & CRTSCTS) {
823 if (ch->ch_flags & CH_RECEIVER_OFF) {
824 bd_ops->enable_receiver(ch);
825 ch->ch_flags &= ~(CH_RECEIVER_OFF);
826 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
827 "Internal queue hit lowlevel mark (%d)! Turning on interrupts.\n",
828 qleft);
829 }
830 }
831 /* SWFLOW */
832 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
833 ch->ch_stops_sent = 0;
834 bd_ops->send_start_character(ch);
835 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "Sending start char!\n");
836 }
837 }
838}
839
840/*
841 * jsm_tty_write()
842 *
843 * Take data from the user or kernel and send it out to the FEP.
844 * In here exists all the Transparent Print magic as well.
845 */
846int jsm_tty_write(struct uart_port *port)
847{
848 int bufcount;
849 int data_count = 0,data_count1 =0;
850 u16 head;
851 u16 tail;
852 u16 tmask;
853 u32 remain;
854 int temp_tail = port->state->xmit.tail;
855 struct jsm_channel *channel = (struct jsm_channel *)port;
856
857 tmask = WQUEUEMASK;
858 head = (channel->ch_w_head) & tmask;
859 tail = (channel->ch_w_tail) & tmask;
860
861 if ((bufcount = tail - head - 1) < 0)
862 bufcount += WQUEUESIZE;
863
864 bufcount = min(bufcount, 56);
865 remain = WQUEUESIZE - head;
866
867 data_count = 0;
868 if (bufcount >= remain) {
869 bufcount -= remain;
870 while ((port->state->xmit.head != temp_tail) &&
871 (data_count < remain)) {
872 channel->ch_wqueue[head++] =
873 port->state->xmit.buf[temp_tail];
874
875 temp_tail++;
876 temp_tail &= (UART_XMIT_SIZE - 1);
877 data_count++;
878 }
879 if (data_count == remain) head = 0;
880 }
881
882 data_count1 = 0;
883 if (bufcount > 0) {
884 remain = bufcount;
885 while ((port->state->xmit.head != temp_tail) &&
886 (data_count1 < remain)) {
887 channel->ch_wqueue[head++] =
888 port->state->xmit.buf[temp_tail];
889
890 temp_tail++;
891 temp_tail &= (UART_XMIT_SIZE - 1);
892 data_count1++;
893
894 }
895 }
896
897 port->state->xmit.tail = temp_tail;
898
899 data_count += data_count1;
900 if (data_count) {
901 head &= tmask;
902 channel->ch_w_head = head;
903 }
904
905 if (data_count) {
906 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
907 }
908
909 return data_count;
910}
1/************************************************************************
2 * Copyright 2003 Digi International (www.digi.com)
3 *
4 * Copyright (C) 2004 IBM Corporation. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2, or (at your option)
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
13 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
14 * PURPOSE. See the GNU General Public License for more details.
15 *
16 * Contact Information:
17 * Scott H Kilau <Scott_Kilau@digi.com>
18 * Ananda Venkatarman <mansarov@us.ibm.com>
19 * Modifications:
20 * 01/19/06: changed jsm_input routine to use the dynamically allocated
21 * tty_buffer changes. Contributors: Scott Kilau and Ananda V.
22 ***********************************************************************/
23#include <linux/tty.h>
24#include <linux/tty_flip.h>
25#include <linux/serial_reg.h>
26#include <linux/delay.h> /* For udelay */
27#include <linux/pci.h>
28#include <linux/slab.h>
29
30#include "jsm.h"
31
32static DECLARE_BITMAP(linemap, MAXLINES);
33
34static void jsm_carrier(struct jsm_channel *ch);
35
36static inline int jsm_get_mstat(struct jsm_channel *ch)
37{
38 unsigned char mstat;
39 unsigned result;
40
41 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "start\n");
42
43 mstat = (ch->ch_mostat | ch->ch_mistat);
44
45 result = 0;
46
47 if (mstat & UART_MCR_DTR)
48 result |= TIOCM_DTR;
49 if (mstat & UART_MCR_RTS)
50 result |= TIOCM_RTS;
51 if (mstat & UART_MSR_CTS)
52 result |= TIOCM_CTS;
53 if (mstat & UART_MSR_DSR)
54 result |= TIOCM_DSR;
55 if (mstat & UART_MSR_RI)
56 result |= TIOCM_RI;
57 if (mstat & UART_MSR_DCD)
58 result |= TIOCM_CD;
59
60 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
61 return result;
62}
63
64static unsigned int jsm_tty_tx_empty(struct uart_port *port)
65{
66 return TIOCSER_TEMT;
67}
68
69/*
70 * Return modem signals to ld.
71 */
72static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
73{
74 int result;
75 struct jsm_channel *channel =
76 container_of(port, struct jsm_channel, uart_port);
77
78 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
79
80 result = jsm_get_mstat(channel);
81
82 if (result < 0)
83 return -ENXIO;
84
85 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
86
87 return result;
88}
89
90/*
91 * jsm_set_modem_info()
92 *
93 * Set modem signals, called by ld.
94 */
95static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
96{
97 struct jsm_channel *channel =
98 container_of(port, struct jsm_channel, uart_port);
99
100 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
101
102 if (mctrl & TIOCM_RTS)
103 channel->ch_mostat |= UART_MCR_RTS;
104 else
105 channel->ch_mostat &= ~UART_MCR_RTS;
106
107 if (mctrl & TIOCM_DTR)
108 channel->ch_mostat |= UART_MCR_DTR;
109 else
110 channel->ch_mostat &= ~UART_MCR_DTR;
111
112 channel->ch_bd->bd_ops->assert_modem_signals(channel);
113
114 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
115 udelay(10);
116}
117
118/*
119 * jsm_tty_write()
120 *
121 * Take data from the user or kernel and send it out to the FEP.
122 * In here exists all the Transparent Print magic as well.
123 */
124static void jsm_tty_write(struct uart_port *port)
125{
126 struct jsm_channel *channel;
127 channel = container_of(port, struct jsm_channel, uart_port);
128 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
129}
130
131static void jsm_tty_start_tx(struct uart_port *port)
132{
133 struct jsm_channel *channel =
134 container_of(port, struct jsm_channel, uart_port);
135
136 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
137
138 channel->ch_flags &= ~(CH_STOP);
139 jsm_tty_write(port);
140
141 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
142}
143
144static void jsm_tty_stop_tx(struct uart_port *port)
145{
146 struct jsm_channel *channel =
147 container_of(port, struct jsm_channel, uart_port);
148
149 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
150
151 channel->ch_flags |= (CH_STOP);
152
153 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
154}
155
156static void jsm_tty_send_xchar(struct uart_port *port, char ch)
157{
158 unsigned long lock_flags;
159 struct jsm_channel *channel =
160 container_of(port, struct jsm_channel, uart_port);
161 struct ktermios *termios;
162
163 spin_lock_irqsave(&port->lock, lock_flags);
164 termios = &port->state->port.tty->termios;
165 if (ch == termios->c_cc[VSTART])
166 channel->ch_bd->bd_ops->send_start_character(channel);
167
168 if (ch == termios->c_cc[VSTOP])
169 channel->ch_bd->bd_ops->send_stop_character(channel);
170 spin_unlock_irqrestore(&port->lock, lock_flags);
171}
172
173static void jsm_tty_stop_rx(struct uart_port *port)
174{
175 struct jsm_channel *channel =
176 container_of(port, struct jsm_channel, uart_port);
177
178 channel->ch_bd->bd_ops->disable_receiver(channel);
179}
180
181static void jsm_tty_break(struct uart_port *port, int break_state)
182{
183 unsigned long lock_flags;
184 struct jsm_channel *channel =
185 container_of(port, struct jsm_channel, uart_port);
186
187 spin_lock_irqsave(&port->lock, lock_flags);
188 if (break_state == -1)
189 channel->ch_bd->bd_ops->send_break(channel);
190 else
191 channel->ch_bd->bd_ops->clear_break(channel);
192
193 spin_unlock_irqrestore(&port->lock, lock_flags);
194}
195
196static int jsm_tty_open(struct uart_port *port)
197{
198 struct jsm_board *brd;
199 struct jsm_channel *channel =
200 container_of(port, struct jsm_channel, uart_port);
201 struct ktermios *termios;
202
203 /* Get board pointer from our array of majors we have allocated */
204 brd = channel->ch_bd;
205
206 /*
207 * Allocate channel buffers for read/write/error.
208 * Set flag, so we don't get trounced on.
209 */
210 channel->ch_flags |= (CH_OPENING);
211
212 /* Drop locks, as malloc with GFP_KERNEL can sleep */
213
214 if (!channel->ch_rqueue) {
215 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
216 if (!channel->ch_rqueue) {
217 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
218 "unable to allocate read queue buf\n");
219 return -ENOMEM;
220 }
221 }
222 if (!channel->ch_equeue) {
223 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
224 if (!channel->ch_equeue) {
225 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
226 "unable to allocate error queue buf\n");
227 return -ENOMEM;
228 }
229 }
230
231 channel->ch_flags &= ~(CH_OPENING);
232 /*
233 * Initialize if neither terminal is open.
234 */
235 jsm_dbg(OPEN, &channel->ch_bd->pci_dev,
236 "jsm_open: initializing channel in open...\n");
237
238 /*
239 * Flush input queues.
240 */
241 channel->ch_r_head = channel->ch_r_tail = 0;
242 channel->ch_e_head = channel->ch_e_tail = 0;
243
244 brd->bd_ops->flush_uart_write(channel);
245 brd->bd_ops->flush_uart_read(channel);
246
247 channel->ch_flags = 0;
248 channel->ch_cached_lsr = 0;
249 channel->ch_stops_sent = 0;
250
251 termios = &port->state->port.tty->termios;
252 channel->ch_c_cflag = termios->c_cflag;
253 channel->ch_c_iflag = termios->c_iflag;
254 channel->ch_c_oflag = termios->c_oflag;
255 channel->ch_c_lflag = termios->c_lflag;
256 channel->ch_startc = termios->c_cc[VSTART];
257 channel->ch_stopc = termios->c_cc[VSTOP];
258
259 /* Tell UART to init itself */
260 brd->bd_ops->uart_init(channel);
261
262 /*
263 * Run param in case we changed anything
264 */
265 brd->bd_ops->param(channel);
266
267 jsm_carrier(channel);
268
269 channel->ch_open_count++;
270
271 jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n");
272 return 0;
273}
274
275static void jsm_tty_close(struct uart_port *port)
276{
277 struct jsm_board *bd;
278 struct ktermios *ts;
279 struct jsm_channel *channel =
280 container_of(port, struct jsm_channel, uart_port);
281
282 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "start\n");
283
284 bd = channel->ch_bd;
285 ts = &port->state->port.tty->termios;
286
287 channel->ch_flags &= ~(CH_STOPI);
288
289 channel->ch_open_count--;
290
291 /*
292 * If we have HUPCL set, lower DTR and RTS
293 */
294 if (channel->ch_c_cflag & HUPCL) {
295 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev,
296 "Close. HUPCL set, dropping DTR/RTS\n");
297
298 /* Drop RTS/DTR */
299 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
300 bd->bd_ops->assert_modem_signals(channel);
301 }
302
303 /* Turn off UART interrupts for this port */
304 channel->ch_bd->bd_ops->uart_off(channel);
305
306 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "finish\n");
307}
308
309static void jsm_tty_set_termios(struct uart_port *port,
310 struct ktermios *termios,
311 struct ktermios *old_termios)
312{
313 unsigned long lock_flags;
314 struct jsm_channel *channel =
315 container_of(port, struct jsm_channel, uart_port);
316
317 spin_lock_irqsave(&port->lock, lock_flags);
318 channel->ch_c_cflag = termios->c_cflag;
319 channel->ch_c_iflag = termios->c_iflag;
320 channel->ch_c_oflag = termios->c_oflag;
321 channel->ch_c_lflag = termios->c_lflag;
322 channel->ch_startc = termios->c_cc[VSTART];
323 channel->ch_stopc = termios->c_cc[VSTOP];
324
325 channel->ch_bd->bd_ops->param(channel);
326 jsm_carrier(channel);
327 spin_unlock_irqrestore(&port->lock, lock_flags);
328}
329
330static const char *jsm_tty_type(struct uart_port *port)
331{
332 return "jsm";
333}
334
335static void jsm_tty_release_port(struct uart_port *port)
336{
337}
338
339static int jsm_tty_request_port(struct uart_port *port)
340{
341 return 0;
342}
343
344static void jsm_config_port(struct uart_port *port, int flags)
345{
346 port->type = PORT_JSM;
347}
348
349static struct uart_ops jsm_ops = {
350 .tx_empty = jsm_tty_tx_empty,
351 .set_mctrl = jsm_tty_set_mctrl,
352 .get_mctrl = jsm_tty_get_mctrl,
353 .stop_tx = jsm_tty_stop_tx,
354 .start_tx = jsm_tty_start_tx,
355 .send_xchar = jsm_tty_send_xchar,
356 .stop_rx = jsm_tty_stop_rx,
357 .break_ctl = jsm_tty_break,
358 .startup = jsm_tty_open,
359 .shutdown = jsm_tty_close,
360 .set_termios = jsm_tty_set_termios,
361 .type = jsm_tty_type,
362 .release_port = jsm_tty_release_port,
363 .request_port = jsm_tty_request_port,
364 .config_port = jsm_config_port,
365};
366
367/*
368 * jsm_tty_init()
369 *
370 * Init the tty subsystem. Called once per board after board has been
371 * downloaded and init'ed.
372 */
373int jsm_tty_init(struct jsm_board *brd)
374{
375 int i;
376 void __iomem *vaddr;
377 struct jsm_channel *ch;
378
379 if (!brd)
380 return -ENXIO;
381
382 jsm_dbg(INIT, &brd->pci_dev, "start\n");
383
384 /*
385 * Initialize board structure elements.
386 */
387
388 brd->nasync = brd->maxports;
389
390 /*
391 * Allocate channel memory that might not have been allocated
392 * when the driver was first loaded.
393 */
394 for (i = 0; i < brd->nasync; i++) {
395 if (!brd->channels[i]) {
396
397 /*
398 * Okay to malloc with GFP_KERNEL, we are not at
399 * interrupt context, and there are no locks held.
400 */
401 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
402 if (!brd->channels[i]) {
403 jsm_dbg(CORE, &brd->pci_dev,
404 "%s:%d Unable to allocate memory for channel struct\n",
405 __FILE__, __LINE__);
406 }
407 }
408 }
409
410 ch = brd->channels[0];
411 vaddr = brd->re_map_membase;
412
413 /* Set up channel variables */
414 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
415
416 if (!brd->channels[i])
417 continue;
418
419 spin_lock_init(&ch->ch_lock);
420
421 if (brd->bd_uart_offset == 0x200)
422 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i);
423 else
424 ch->ch_cls_uart = vaddr + (brd->bd_uart_offset * i);
425
426 ch->ch_bd = brd;
427 ch->ch_portnum = i;
428
429 /* .25 second delay */
430 ch->ch_close_delay = 250;
431
432 init_waitqueue_head(&ch->ch_flags_wait);
433 }
434
435 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
436 return 0;
437}
438
439int jsm_uart_port_init(struct jsm_board *brd)
440{
441 int i, rc;
442 unsigned int line;
443 struct jsm_channel *ch;
444
445 if (!brd)
446 return -ENXIO;
447
448 jsm_dbg(INIT, &brd->pci_dev, "start\n");
449
450 /*
451 * Initialize board structure elements.
452 */
453
454 brd->nasync = brd->maxports;
455
456 /* Set up channel variables */
457 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
458
459 if (!brd->channels[i])
460 continue;
461
462 brd->channels[i]->uart_port.irq = brd->irq;
463 brd->channels[i]->uart_port.uartclk = 14745600;
464 brd->channels[i]->uart_port.type = PORT_JSM;
465 brd->channels[i]->uart_port.iotype = UPIO_MEM;
466 brd->channels[i]->uart_port.membase = brd->re_map_membase;
467 brd->channels[i]->uart_port.fifosize = 16;
468 brd->channels[i]->uart_port.ops = &jsm_ops;
469 line = find_first_zero_bit(linemap, MAXLINES);
470 if (line >= MAXLINES) {
471 printk(KERN_INFO "jsm: linemap is full, added device failed\n");
472 continue;
473 } else
474 set_bit(line, linemap);
475 brd->channels[i]->uart_port.line = line;
476 rc = uart_add_one_port (&jsm_uart_driver, &brd->channels[i]->uart_port);
477 if (rc){
478 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
479 return rc;
480 }
481 else
482 printk(KERN_INFO "jsm: Port %d added\n", i);
483 }
484
485 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
486 return 0;
487}
488
489int jsm_remove_uart_port(struct jsm_board *brd)
490{
491 int i;
492 struct jsm_channel *ch;
493
494 if (!brd)
495 return -ENXIO;
496
497 jsm_dbg(INIT, &brd->pci_dev, "start\n");
498
499 /*
500 * Initialize board structure elements.
501 */
502
503 brd->nasync = brd->maxports;
504
505 /* Set up channel variables */
506 for (i = 0; i < brd->nasync; i++) {
507
508 if (!brd->channels[i])
509 continue;
510
511 ch = brd->channels[i];
512
513 clear_bit(ch->uart_port.line, linemap);
514 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
515 }
516
517 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
518 return 0;
519}
520
521void jsm_input(struct jsm_channel *ch)
522{
523 struct jsm_board *bd;
524 struct tty_struct *tp;
525 struct tty_port *port;
526 u32 rmask;
527 u16 head;
528 u16 tail;
529 int data_len;
530 unsigned long lock_flags;
531 int len = 0;
532 int s = 0;
533 int i = 0;
534
535 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
536
537 if (!ch)
538 return;
539
540 port = &ch->uart_port.state->port;
541 tp = port->tty;
542
543 bd = ch->ch_bd;
544 if(!bd)
545 return;
546
547 spin_lock_irqsave(&ch->ch_lock, lock_flags);
548
549 /*
550 *Figure the number of characters in the buffer.
551 *Exit immediately if none.
552 */
553
554 rmask = RQUEUEMASK;
555
556 head = ch->ch_r_head & rmask;
557 tail = ch->ch_r_tail & rmask;
558
559 data_len = (head - tail) & rmask;
560 if (data_len == 0) {
561 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
562 return;
563 }
564
565 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
566
567 /*
568 *If the device is not open, or CREAD is off, flush
569 *input data and return immediately.
570 */
571 if (!tp || !C_CREAD(tp)) {
572
573 jsm_dbg(READ, &ch->ch_bd->pci_dev,
574 "input. dropping %d bytes on port %d...\n",
575 data_len, ch->ch_portnum);
576 ch->ch_r_head = tail;
577
578 /* Force queue flow control to be released, if needed */
579 jsm_check_queue_flow_control(ch);
580
581 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
582 return;
583 }
584
585 /*
586 * If we are throttled, simply don't read any data.
587 */
588 if (ch->ch_flags & CH_STOPI) {
589 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
590 jsm_dbg(READ, &ch->ch_bd->pci_dev,
591 "Port %d throttled, not reading any data. head: %x tail: %x\n",
592 ch->ch_portnum, head, tail);
593 return;
594 }
595
596 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n");
597
598 len = tty_buffer_request_room(port, data_len);
599
600 /*
601 * len now contains the most amount of data we can copy,
602 * bounded either by the flip buffer size or the amount
603 * of data the card actually has pending...
604 */
605 while (len) {
606 s = ((head >= tail) ? head : RQUEUESIZE) - tail;
607 s = min(s, len);
608
609 if (s <= 0)
610 break;
611
612 /*
613 * If conditions are such that ld needs to see all
614 * UART errors, we will have to walk each character
615 * and error byte and send them to the buffer one at
616 * a time.
617 */
618
619 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
620 for (i = 0; i < s; i++) {
621 /*
622 * Give the Linux ld the flags in the
623 * format it likes.
624 */
625 if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
626 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_BREAK);
627 else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
628 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_PARITY);
629 else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
630 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_FRAME);
631 else
632 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
633 }
634 } else {
635 tty_insert_flip_string(port, ch->ch_rqueue + tail, s);
636 }
637 tail += s;
638 len -= s;
639 /* Flip queue if needed */
640 tail &= rmask;
641 }
642
643 ch->ch_r_tail = tail & rmask;
644 ch->ch_e_tail = tail & rmask;
645 jsm_check_queue_flow_control(ch);
646 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
647
648 /* Tell the tty layer its okay to "eat" the data now */
649 tty_flip_buffer_push(port);
650
651 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
652}
653
654static void jsm_carrier(struct jsm_channel *ch)
655{
656 struct jsm_board *bd;
657
658 int virt_carrier = 0;
659 int phys_carrier = 0;
660
661 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "start\n");
662 if (!ch)
663 return;
664
665 bd = ch->ch_bd;
666
667 if (!bd)
668 return;
669
670 if (ch->ch_mistat & UART_MSR_DCD) {
671 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "mistat: %x D_CD: %x\n",
672 ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
673 phys_carrier = 1;
674 }
675
676 if (ch->ch_c_cflag & CLOCAL)
677 virt_carrier = 1;
678
679 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "DCD: physical: %d virt: %d\n",
680 phys_carrier, virt_carrier);
681
682 /*
683 * Test for a VIRTUAL carrier transition to HIGH.
684 */
685 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
686
687 /*
688 * When carrier rises, wake any threads waiting
689 * for carrier in the open routine.
690 */
691
692 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "carrier: virt DCD rose\n");
693
694 if (waitqueue_active(&(ch->ch_flags_wait)))
695 wake_up_interruptible(&ch->ch_flags_wait);
696 }
697
698 /*
699 * Test for a PHYSICAL carrier transition to HIGH.
700 */
701 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
702
703 /*
704 * When carrier rises, wake any threads waiting
705 * for carrier in the open routine.
706 */
707
708 jsm_dbg(CARR, &ch->ch_bd->pci_dev,
709 "carrier: physical DCD rose\n");
710
711 if (waitqueue_active(&(ch->ch_flags_wait)))
712 wake_up_interruptible(&ch->ch_flags_wait);
713 }
714
715 /*
716 * Test for a PHYSICAL transition to low, so long as we aren't
717 * currently ignoring physical transitions (which is what "virtual
718 * carrier" indicates).
719 *
720 * The transition of the virtual carrier to low really doesn't
721 * matter... it really only means "ignore carrier state", not
722 * "make pretend that carrier is there".
723 */
724 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
725 && (phys_carrier == 0)) {
726 /*
727 * When carrier drops:
728 *
729 * Drop carrier on all open units.
730 *
731 * Flush queues, waking up any task waiting in the
732 * line discipline.
733 *
734 * Send a hangup to the control terminal.
735 *
736 * Enable all select calls.
737 */
738 if (waitqueue_active(&(ch->ch_flags_wait)))
739 wake_up_interruptible(&ch->ch_flags_wait);
740 }
741
742 /*
743 * Make sure that our cached values reflect the current reality.
744 */
745 if (virt_carrier == 1)
746 ch->ch_flags |= CH_FCAR;
747 else
748 ch->ch_flags &= ~CH_FCAR;
749
750 if (phys_carrier == 1)
751 ch->ch_flags |= CH_CD;
752 else
753 ch->ch_flags &= ~CH_CD;
754}
755
756
757void jsm_check_queue_flow_control(struct jsm_channel *ch)
758{
759 struct board_ops *bd_ops = ch->ch_bd->bd_ops;
760 int qleft;
761
762 /* Store how much space we have left in the queue */
763 if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
764 qleft += RQUEUEMASK + 1;
765
766 /*
767 * Check to see if we should enforce flow control on our queue because
768 * the ld (or user) isn't reading data out of our queue fast enuf.
769 *
770 * NOTE: This is done based on what the current flow control of the
771 * port is set for.
772 *
773 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
774 * This will cause the UART's FIFO to back up, and force
775 * the RTS signal to be dropped.
776 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
777 * the other side, in hopes it will stop sending data to us.
778 * 3) NONE - Nothing we can do. We will simply drop any extra data
779 * that gets sent into us when the queue fills up.
780 */
781 if (qleft < 256) {
782 /* HWFLOW */
783 if (ch->ch_c_cflag & CRTSCTS) {
784 if(!(ch->ch_flags & CH_RECEIVER_OFF)) {
785 bd_ops->disable_receiver(ch);
786 ch->ch_flags |= (CH_RECEIVER_OFF);
787 jsm_dbg(READ, &ch->ch_bd->pci_dev,
788 "Internal queue hit hilevel mark (%d)! Turning off interrupts\n",
789 qleft);
790 }
791 }
792 /* SWFLOW */
793 else if (ch->ch_c_iflag & IXOFF) {
794 if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
795 bd_ops->send_stop_character(ch);
796 ch->ch_stops_sent++;
797 jsm_dbg(READ, &ch->ch_bd->pci_dev,
798 "Sending stop char! Times sent: %x\n",
799 ch->ch_stops_sent);
800 }
801 }
802 }
803
804 /*
805 * Check to see if we should unenforce flow control because
806 * ld (or user) finally read enuf data out of our queue.
807 *
808 * NOTE: This is done based on what the current flow control of the
809 * port is set for.
810 *
811 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
812 * This will cause the UART's FIFO to raise RTS back up,
813 * which will allow the other side to start sending data again.
814 * 2) SWFLOW (IXOFF) - Send a start character to
815 * the other side, so it will start sending data to us again.
816 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
817 * other side, we don't need to do anything now.
818 */
819 if (qleft > (RQUEUESIZE / 2)) {
820 /* HWFLOW */
821 if (ch->ch_c_cflag & CRTSCTS) {
822 if (ch->ch_flags & CH_RECEIVER_OFF) {
823 bd_ops->enable_receiver(ch);
824 ch->ch_flags &= ~(CH_RECEIVER_OFF);
825 jsm_dbg(READ, &ch->ch_bd->pci_dev,
826 "Internal queue hit lowlevel mark (%d)! Turning on interrupts\n",
827 qleft);
828 }
829 }
830 /* SWFLOW */
831 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
832 ch->ch_stops_sent = 0;
833 bd_ops->send_start_character(ch);
834 jsm_dbg(READ, &ch->ch_bd->pci_dev,
835 "Sending start char!\n");
836 }
837 }
838}