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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// SPDX-License-Identifier: GPL-2.0+
2/************************************************************************
3 * Copyright 2003 Digi International (www.digi.com)
4 *
5 * Copyright (C) 2004 IBM Corporation. All rights reserved.
6 *
7 * Contact Information:
8 * Scott H Kilau <Scott_Kilau@digi.com>
9 * Ananda Venkatarman <mansarov@us.ibm.com>
10 * Modifications:
11 * 01/19/06: changed jsm_input routine to use the dynamically allocated
12 * tty_buffer changes. Contributors: Scott Kilau and Ananda V.
13 ***********************************************************************/
14#include <linux/tty.h>
15#include <linux/tty_flip.h>
16#include <linux/serial_reg.h>
17#include <linux/delay.h> /* For udelay */
18#include <linux/pci.h>
19#include <linux/slab.h>
20
21#include "jsm.h"
22
23static DECLARE_BITMAP(linemap, MAXLINES);
24
25static void jsm_carrier(struct jsm_channel *ch);
26
27static inline int jsm_get_mstat(struct jsm_channel *ch)
28{
29 unsigned char mstat;
30 int result;
31
32 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "start\n");
33
34 mstat = (ch->ch_mostat | ch->ch_mistat);
35
36 result = 0;
37
38 if (mstat & UART_MCR_DTR)
39 result |= TIOCM_DTR;
40 if (mstat & UART_MCR_RTS)
41 result |= TIOCM_RTS;
42 if (mstat & UART_MSR_CTS)
43 result |= TIOCM_CTS;
44 if (mstat & UART_MSR_DSR)
45 result |= TIOCM_DSR;
46 if (mstat & UART_MSR_RI)
47 result |= TIOCM_RI;
48 if (mstat & UART_MSR_DCD)
49 result |= TIOCM_CD;
50
51 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
52 return result;
53}
54
55static unsigned int jsm_tty_tx_empty(struct uart_port *port)
56{
57 return TIOCSER_TEMT;
58}
59
60/*
61 * Return modem signals to ld.
62 */
63static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
64{
65 int result;
66 struct jsm_channel *channel =
67 container_of(port, struct jsm_channel, uart_port);
68
69 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
70
71 result = jsm_get_mstat(channel);
72
73 if (result < 0)
74 return -ENXIO;
75
76 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
77
78 return result;
79}
80
81/*
82 * jsm_set_modem_info()
83 *
84 * Set modem signals, called by ld.
85 */
86static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
87{
88 struct jsm_channel *channel =
89 container_of(port, struct jsm_channel, uart_port);
90
91 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
92
93 if (mctrl & TIOCM_RTS)
94 channel->ch_mostat |= UART_MCR_RTS;
95 else
96 channel->ch_mostat &= ~UART_MCR_RTS;
97
98 if (mctrl & TIOCM_DTR)
99 channel->ch_mostat |= UART_MCR_DTR;
100 else
101 channel->ch_mostat &= ~UART_MCR_DTR;
102
103 channel->ch_bd->bd_ops->assert_modem_signals(channel);
104
105 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
106 udelay(10);
107}
108
109/*
110 * jsm_tty_write()
111 *
112 * Take data from the user or kernel and send it out to the FEP.
113 * In here exists all the Transparent Print magic as well.
114 */
115static void jsm_tty_write(struct uart_port *port)
116{
117 struct jsm_channel *channel;
118
119 channel = container_of(port, struct jsm_channel, uart_port);
120 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
121}
122
123static void jsm_tty_start_tx(struct uart_port *port)
124{
125 struct jsm_channel *channel =
126 container_of(port, struct jsm_channel, uart_port);
127
128 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
129
130 channel->ch_flags &= ~(CH_STOP);
131 jsm_tty_write(port);
132
133 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
134}
135
136static void jsm_tty_stop_tx(struct uart_port *port)
137{
138 struct jsm_channel *channel =
139 container_of(port, struct jsm_channel, uart_port);
140
141 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
142
143 channel->ch_flags |= (CH_STOP);
144
145 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
146}
147
148static void jsm_tty_send_xchar(struct uart_port *port, char ch)
149{
150 unsigned long lock_flags;
151 struct jsm_channel *channel =
152 container_of(port, struct jsm_channel, uart_port);
153 struct ktermios *termios;
154
155 spin_lock_irqsave(&port->lock, lock_flags);
156 termios = &port->state->port.tty->termios;
157 if (ch == termios->c_cc[VSTART])
158 channel->ch_bd->bd_ops->send_start_character(channel);
159
160 if (ch == termios->c_cc[VSTOP])
161 channel->ch_bd->bd_ops->send_stop_character(channel);
162 spin_unlock_irqrestore(&port->lock, lock_flags);
163}
164
165static void jsm_tty_stop_rx(struct uart_port *port)
166{
167 struct jsm_channel *channel =
168 container_of(port, struct jsm_channel, uart_port);
169
170 channel->ch_bd->bd_ops->disable_receiver(channel);
171}
172
173static void jsm_tty_break(struct uart_port *port, int break_state)
174{
175 unsigned long lock_flags;
176 struct jsm_channel *channel =
177 container_of(port, struct jsm_channel, uart_port);
178
179 spin_lock_irqsave(&port->lock, lock_flags);
180 if (break_state == -1)
181 channel->ch_bd->bd_ops->send_break(channel);
182 else
183 channel->ch_bd->bd_ops->clear_break(channel);
184
185 spin_unlock_irqrestore(&port->lock, lock_flags);
186}
187
188static int jsm_tty_open(struct uart_port *port)
189{
190 struct jsm_board *brd;
191 struct jsm_channel *channel =
192 container_of(port, struct jsm_channel, uart_port);
193 struct ktermios *termios;
194
195 /* Get board pointer from our array of majors we have allocated */
196 brd = channel->ch_bd;
197
198 /*
199 * Allocate channel buffers for read/write/error.
200 * Set flag, so we don't get trounced on.
201 */
202 channel->ch_flags |= (CH_OPENING);
203
204 /* Drop locks, as malloc with GFP_KERNEL can sleep */
205
206 if (!channel->ch_rqueue) {
207 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
208 if (!channel->ch_rqueue) {
209 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
210 "unable to allocate read queue buf\n");
211 return -ENOMEM;
212 }
213 }
214 if (!channel->ch_equeue) {
215 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
216 if (!channel->ch_equeue) {
217 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
218 "unable to allocate error queue buf\n");
219 return -ENOMEM;
220 }
221 }
222
223 channel->ch_flags &= ~(CH_OPENING);
224 /*
225 * Initialize if neither terminal is open.
226 */
227 jsm_dbg(OPEN, &channel->ch_bd->pci_dev,
228 "jsm_open: initializing channel in open...\n");
229
230 /*
231 * Flush input queues.
232 */
233 channel->ch_r_head = channel->ch_r_tail = 0;
234 channel->ch_e_head = channel->ch_e_tail = 0;
235
236 brd->bd_ops->flush_uart_write(channel);
237 brd->bd_ops->flush_uart_read(channel);
238
239 channel->ch_flags = 0;
240 channel->ch_cached_lsr = 0;
241 channel->ch_stops_sent = 0;
242
243 termios = &port->state->port.tty->termios;
244 channel->ch_c_cflag = termios->c_cflag;
245 channel->ch_c_iflag = termios->c_iflag;
246 channel->ch_c_oflag = termios->c_oflag;
247 channel->ch_c_lflag = termios->c_lflag;
248 channel->ch_startc = termios->c_cc[VSTART];
249 channel->ch_stopc = termios->c_cc[VSTOP];
250
251 /* Tell UART to init itself */
252 brd->bd_ops->uart_init(channel);
253
254 /*
255 * Run param in case we changed anything
256 */
257 brd->bd_ops->param(channel);
258
259 jsm_carrier(channel);
260
261 channel->ch_open_count++;
262
263 jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n");
264 return 0;
265}
266
267static void jsm_tty_close(struct uart_port *port)
268{
269 struct jsm_board *bd;
270 struct jsm_channel *channel =
271 container_of(port, struct jsm_channel, uart_port);
272
273 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "start\n");
274
275 bd = channel->ch_bd;
276
277 channel->ch_flags &= ~(CH_STOPI);
278
279 channel->ch_open_count--;
280
281 /*
282 * If we have HUPCL set, lower DTR and RTS
283 */
284 if (channel->ch_c_cflag & HUPCL) {
285 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev,
286 "Close. HUPCL set, dropping DTR/RTS\n");
287
288 /* Drop RTS/DTR */
289 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
290 bd->bd_ops->assert_modem_signals(channel);
291 }
292
293 /* Turn off UART interrupts for this port */
294 channel->ch_bd->bd_ops->uart_off(channel);
295
296 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "finish\n");
297}
298
299static void jsm_tty_set_termios(struct uart_port *port,
300 struct ktermios *termios,
301 struct ktermios *old_termios)
302{
303 unsigned long lock_flags;
304 struct jsm_channel *channel =
305 container_of(port, struct jsm_channel, uart_port);
306
307 spin_lock_irqsave(&port->lock, lock_flags);
308 channel->ch_c_cflag = termios->c_cflag;
309 channel->ch_c_iflag = termios->c_iflag;
310 channel->ch_c_oflag = termios->c_oflag;
311 channel->ch_c_lflag = termios->c_lflag;
312 channel->ch_startc = termios->c_cc[VSTART];
313 channel->ch_stopc = termios->c_cc[VSTOP];
314
315 channel->ch_bd->bd_ops->param(channel);
316 jsm_carrier(channel);
317 spin_unlock_irqrestore(&port->lock, lock_flags);
318}
319
320static const char *jsm_tty_type(struct uart_port *port)
321{
322 return "jsm";
323}
324
325static void jsm_tty_release_port(struct uart_port *port)
326{
327}
328
329static int jsm_tty_request_port(struct uart_port *port)
330{
331 return 0;
332}
333
334static void jsm_config_port(struct uart_port *port, int flags)
335{
336 port->type = PORT_JSM;
337}
338
339static const struct uart_ops jsm_ops = {
340 .tx_empty = jsm_tty_tx_empty,
341 .set_mctrl = jsm_tty_set_mctrl,
342 .get_mctrl = jsm_tty_get_mctrl,
343 .stop_tx = jsm_tty_stop_tx,
344 .start_tx = jsm_tty_start_tx,
345 .send_xchar = jsm_tty_send_xchar,
346 .stop_rx = jsm_tty_stop_rx,
347 .break_ctl = jsm_tty_break,
348 .startup = jsm_tty_open,
349 .shutdown = jsm_tty_close,
350 .set_termios = jsm_tty_set_termios,
351 .type = jsm_tty_type,
352 .release_port = jsm_tty_release_port,
353 .request_port = jsm_tty_request_port,
354 .config_port = jsm_config_port,
355};
356
357/*
358 * jsm_tty_init()
359 *
360 * Init the tty subsystem. Called once per board after board has been
361 * downloaded and init'ed.
362 */
363int jsm_tty_init(struct jsm_board *brd)
364{
365 int i;
366 void __iomem *vaddr;
367 struct jsm_channel *ch;
368
369 if (!brd)
370 return -ENXIO;
371
372 jsm_dbg(INIT, &brd->pci_dev, "start\n");
373
374 /*
375 * Initialize board structure elements.
376 */
377
378 brd->nasync = brd->maxports;
379
380 /*
381 * Allocate channel memory that might not have been allocated
382 * when the driver was first loaded.
383 */
384 for (i = 0; i < brd->nasync; i++) {
385 if (!brd->channels[i]) {
386
387 /*
388 * Okay to malloc with GFP_KERNEL, we are not at
389 * interrupt context, and there are no locks held.
390 */
391 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
392 if (!brd->channels[i]) {
393 jsm_dbg(CORE, &brd->pci_dev,
394 "%s:%d Unable to allocate memory for channel struct\n",
395 __FILE__, __LINE__);
396 }
397 }
398 }
399
400 ch = brd->channels[0];
401 vaddr = brd->re_map_membase;
402
403 /* Set up channel variables */
404 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
405
406 if (!brd->channels[i])
407 continue;
408
409 spin_lock_init(&ch->ch_lock);
410
411 if (brd->bd_uart_offset == 0x200)
412 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i);
413 else
414 ch->ch_cls_uart = vaddr + (brd->bd_uart_offset * i);
415
416 ch->ch_bd = brd;
417 ch->ch_portnum = i;
418
419 /* .25 second delay */
420 ch->ch_close_delay = 250;
421
422 init_waitqueue_head(&ch->ch_flags_wait);
423 }
424
425 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
426 return 0;
427}
428
429int jsm_uart_port_init(struct jsm_board *brd)
430{
431 int i, rc;
432 unsigned int line;
433 struct jsm_channel *ch;
434
435 if (!brd)
436 return -ENXIO;
437
438 jsm_dbg(INIT, &brd->pci_dev, "start\n");
439
440 /*
441 * Initialize board structure elements.
442 */
443
444 brd->nasync = brd->maxports;
445
446 /* Set up channel variables */
447 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
448
449 if (!brd->channels[i])
450 continue;
451
452 brd->channels[i]->uart_port.irq = brd->irq;
453 brd->channels[i]->uart_port.uartclk = 14745600;
454 brd->channels[i]->uart_port.type = PORT_JSM;
455 brd->channels[i]->uart_port.iotype = UPIO_MEM;
456 brd->channels[i]->uart_port.membase = brd->re_map_membase;
457 brd->channels[i]->uart_port.fifosize = 16;
458 brd->channels[i]->uart_port.ops = &jsm_ops;
459 line = find_first_zero_bit(linemap, MAXLINES);
460 if (line >= MAXLINES) {
461 printk(KERN_INFO "jsm: linemap is full, added device failed\n");
462 continue;
463 } else
464 set_bit(line, linemap);
465 brd->channels[i]->uart_port.line = line;
466 rc = uart_add_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
467 if (rc) {
468 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
469 return rc;
470 } else
471 printk(KERN_INFO "jsm: Port %d added\n", i);
472 }
473
474 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
475 return 0;
476}
477
478int jsm_remove_uart_port(struct jsm_board *brd)
479{
480 int i;
481 struct jsm_channel *ch;
482
483 if (!brd)
484 return -ENXIO;
485
486 jsm_dbg(INIT, &brd->pci_dev, "start\n");
487
488 /*
489 * Initialize board structure elements.
490 */
491
492 brd->nasync = brd->maxports;
493
494 /* Set up channel variables */
495 for (i = 0; i < brd->nasync; i++) {
496
497 if (!brd->channels[i])
498 continue;
499
500 ch = brd->channels[i];
501
502 clear_bit(ch->uart_port.line, linemap);
503 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
504 }
505
506 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
507 return 0;
508}
509
510void jsm_input(struct jsm_channel *ch)
511{
512 struct jsm_board *bd;
513 struct tty_struct *tp;
514 struct tty_port *port;
515 u32 rmask;
516 u16 head;
517 u16 tail;
518 int data_len;
519 unsigned long lock_flags;
520 int len = 0;
521 int s = 0;
522 int i = 0;
523
524 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
525
526 port = &ch->uart_port.state->port;
527 tp = port->tty;
528
529 bd = ch->ch_bd;
530 if (!bd)
531 return;
532
533 spin_lock_irqsave(&ch->ch_lock, lock_flags);
534
535 /*
536 *Figure the number of characters in the buffer.
537 *Exit immediately if none.
538 */
539
540 rmask = RQUEUEMASK;
541
542 head = ch->ch_r_head & rmask;
543 tail = ch->ch_r_tail & rmask;
544
545 data_len = (head - tail) & rmask;
546 if (data_len == 0) {
547 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
548 return;
549 }
550
551 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
552
553 /*
554 *If the device is not open, or CREAD is off, flush
555 *input data and return immediately.
556 */
557 if (!tp || !C_CREAD(tp)) {
558
559 jsm_dbg(READ, &ch->ch_bd->pci_dev,
560 "input. dropping %d bytes on port %d...\n",
561 data_len, ch->ch_portnum);
562 ch->ch_r_head = tail;
563
564 /* Force queue flow control to be released, if needed */
565 jsm_check_queue_flow_control(ch);
566
567 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
568 return;
569 }
570
571 /*
572 * If we are throttled, simply don't read any data.
573 */
574 if (ch->ch_flags & CH_STOPI) {
575 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
576 jsm_dbg(READ, &ch->ch_bd->pci_dev,
577 "Port %d throttled, not reading any data. head: %x tail: %x\n",
578 ch->ch_portnum, head, tail);
579 return;
580 }
581
582 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n");
583
584 len = tty_buffer_request_room(port, data_len);
585
586 /*
587 * len now contains the most amount of data we can copy,
588 * bounded either by the flip buffer size or the amount
589 * of data the card actually has pending...
590 */
591 while (len) {
592 s = ((head >= tail) ? head : RQUEUESIZE) - tail;
593 s = min(s, len);
594
595 if (s <= 0)
596 break;
597
598 /*
599 * If conditions are such that ld needs to see all
600 * UART errors, we will have to walk each character
601 * and error byte and send them to the buffer one at
602 * a time.
603 */
604
605 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
606 for (i = 0; i < s; i++) {
607 /*
608 * Give the Linux ld the flags in the
609 * format it likes.
610 */
611 if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
612 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_BREAK);
613 else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
614 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_PARITY);
615 else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
616 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_FRAME);
617 else
618 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
619 }
620 } else {
621 tty_insert_flip_string(port, ch->ch_rqueue + tail, s);
622 }
623 tail += s;
624 len -= s;
625 /* Flip queue if needed */
626 tail &= rmask;
627 }
628
629 ch->ch_r_tail = tail & rmask;
630 ch->ch_e_tail = tail & rmask;
631 jsm_check_queue_flow_control(ch);
632 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
633
634 /* Tell the tty layer its okay to "eat" the data now */
635 tty_flip_buffer_push(port);
636
637 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
638}
639
640static void jsm_carrier(struct jsm_channel *ch)
641{
642 struct jsm_board *bd;
643
644 int virt_carrier = 0;
645 int phys_carrier = 0;
646
647 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "start\n");
648
649 bd = ch->ch_bd;
650 if (!bd)
651 return;
652
653 if (ch->ch_mistat & UART_MSR_DCD) {
654 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "mistat: %x D_CD: %x\n",
655 ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
656 phys_carrier = 1;
657 }
658
659 if (ch->ch_c_cflag & CLOCAL)
660 virt_carrier = 1;
661
662 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "DCD: physical: %d virt: %d\n",
663 phys_carrier, virt_carrier);
664
665 /*
666 * Test for a VIRTUAL carrier transition to HIGH.
667 */
668 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
669
670 /*
671 * When carrier rises, wake any threads waiting
672 * for carrier in the open routine.
673 */
674
675 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "carrier: virt DCD rose\n");
676
677 if (waitqueue_active(&(ch->ch_flags_wait)))
678 wake_up_interruptible(&ch->ch_flags_wait);
679 }
680
681 /*
682 * Test for a PHYSICAL carrier transition to HIGH.
683 */
684 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
685
686 /*
687 * When carrier rises, wake any threads waiting
688 * for carrier in the open routine.
689 */
690
691 jsm_dbg(CARR, &ch->ch_bd->pci_dev,
692 "carrier: physical 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 transition to low, so long as we aren't
700 * currently ignoring physical transitions (which is what "virtual
701 * carrier" indicates).
702 *
703 * The transition of the virtual carrier to low really doesn't
704 * matter... it really only means "ignore carrier state", not
705 * "make pretend that carrier is there".
706 */
707 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
708 && (phys_carrier == 0)) {
709 /*
710 * When carrier drops:
711 *
712 * Drop carrier on all open units.
713 *
714 * Flush queues, waking up any task waiting in the
715 * line discipline.
716 *
717 * Send a hangup to the control terminal.
718 *
719 * Enable all select calls.
720 */
721 if (waitqueue_active(&(ch->ch_flags_wait)))
722 wake_up_interruptible(&ch->ch_flags_wait);
723 }
724
725 /*
726 * Make sure that our cached values reflect the current reality.
727 */
728 if (virt_carrier == 1)
729 ch->ch_flags |= CH_FCAR;
730 else
731 ch->ch_flags &= ~CH_FCAR;
732
733 if (phys_carrier == 1)
734 ch->ch_flags |= CH_CD;
735 else
736 ch->ch_flags &= ~CH_CD;
737}
738
739
740void jsm_check_queue_flow_control(struct jsm_channel *ch)
741{
742 struct board_ops *bd_ops = ch->ch_bd->bd_ops;
743 int qleft;
744
745 /* Store how much space we have left in the queue */
746 if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
747 qleft += RQUEUEMASK + 1;
748
749 /*
750 * Check to see if we should enforce flow control on our queue because
751 * the ld (or user) isn't reading data out of our queue fast enuf.
752 *
753 * NOTE: This is done based on what the current flow control of the
754 * port is set for.
755 *
756 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
757 * This will cause the UART's FIFO to back up, and force
758 * the RTS signal to be dropped.
759 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
760 * the other side, in hopes it will stop sending data to us.
761 * 3) NONE - Nothing we can do. We will simply drop any extra data
762 * that gets sent into us when the queue fills up.
763 */
764 if (qleft < 256) {
765 /* HWFLOW */
766 if (ch->ch_c_cflag & CRTSCTS) {
767 if (!(ch->ch_flags & CH_RECEIVER_OFF)) {
768 bd_ops->disable_receiver(ch);
769 ch->ch_flags |= (CH_RECEIVER_OFF);
770 jsm_dbg(READ, &ch->ch_bd->pci_dev,
771 "Internal queue hit hilevel mark (%d)! Turning off interrupts\n",
772 qleft);
773 }
774 }
775 /* SWFLOW */
776 else if (ch->ch_c_iflag & IXOFF) {
777 if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
778 bd_ops->send_stop_character(ch);
779 ch->ch_stops_sent++;
780 jsm_dbg(READ, &ch->ch_bd->pci_dev,
781 "Sending stop char! Times sent: %x\n",
782 ch->ch_stops_sent);
783 }
784 }
785 }
786
787 /*
788 * Check to see if we should unenforce flow control because
789 * ld (or user) finally read enuf data out of our queue.
790 *
791 * NOTE: This is done based on what the current flow control of the
792 * port is set for.
793 *
794 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
795 * This will cause the UART's FIFO to raise RTS back up,
796 * which will allow the other side to start sending data again.
797 * 2) SWFLOW (IXOFF) - Send a start character to
798 * the other side, so it will start sending data to us again.
799 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
800 * other side, we don't need to do anything now.
801 */
802 if (qleft > (RQUEUESIZE / 2)) {
803 /* HWFLOW */
804 if (ch->ch_c_cflag & CRTSCTS) {
805 if (ch->ch_flags & CH_RECEIVER_OFF) {
806 bd_ops->enable_receiver(ch);
807 ch->ch_flags &= ~(CH_RECEIVER_OFF);
808 jsm_dbg(READ, &ch->ch_bd->pci_dev,
809 "Internal queue hit lowlevel mark (%d)! Turning on interrupts\n",
810 qleft);
811 }
812 }
813 /* SWFLOW */
814 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
815 ch->ch_stops_sent = 0;
816 bd_ops->send_start_character(ch);
817 jsm_dbg(READ, &ch->ch_bd->pci_dev,
818 "Sending start char!\n");
819 }
820 }
821}