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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 uart_port_lock_irqsave(port, &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 uart_port_unlock_irqrestore(port, 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 uart_port_lock_irqsave(port, &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 uart_port_unlock_irqrestore(port, lock_flags);
186}
187
188static int jsm_tty_open(struct uart_port *port)
189{
190 unsigned long lock_flags;
191 struct jsm_board *brd;
192 struct jsm_channel *channel =
193 container_of(port, struct jsm_channel, uart_port);
194 struct ktermios *termios;
195
196 /* Get board pointer from our array of majors we have allocated */
197 brd = channel->ch_bd;
198
199 /*
200 * Allocate channel buffers for read/write/error.
201 * Set flag, so we don't get trounced on.
202 */
203 channel->ch_flags |= (CH_OPENING);
204
205 /* Drop locks, as malloc with GFP_KERNEL can sleep */
206
207 if (!channel->ch_rqueue) {
208 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
209 if (!channel->ch_rqueue) {
210 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
211 "unable to allocate read queue buf\n");
212 return -ENOMEM;
213 }
214 }
215 if (!channel->ch_equeue) {
216 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
217 if (!channel->ch_equeue) {
218 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
219 "unable to allocate error queue buf\n");
220 return -ENOMEM;
221 }
222 }
223
224 channel->ch_flags &= ~(CH_OPENING);
225 /*
226 * Initialize if neither terminal is open.
227 */
228 jsm_dbg(OPEN, &channel->ch_bd->pci_dev,
229 "jsm_open: initializing channel in open...\n");
230
231 /*
232 * Flush input queues.
233 */
234 channel->ch_r_head = channel->ch_r_tail = 0;
235 channel->ch_e_head = channel->ch_e_tail = 0;
236
237 brd->bd_ops->flush_uart_write(channel);
238 brd->bd_ops->flush_uart_read(channel);
239
240 channel->ch_flags = 0;
241 channel->ch_cached_lsr = 0;
242 channel->ch_stops_sent = 0;
243
244 uart_port_lock_irqsave(port, &lock_flags);
245 termios = &port->state->port.tty->termios;
246 channel->ch_c_cflag = termios->c_cflag;
247 channel->ch_c_iflag = termios->c_iflag;
248 channel->ch_c_oflag = termios->c_oflag;
249 channel->ch_c_lflag = termios->c_lflag;
250 channel->ch_startc = termios->c_cc[VSTART];
251 channel->ch_stopc = termios->c_cc[VSTOP];
252
253 /* Tell UART to init itself */
254 brd->bd_ops->uart_init(channel);
255
256 /*
257 * Run param in case we changed anything
258 */
259 brd->bd_ops->param(channel);
260
261 jsm_carrier(channel);
262
263 channel->ch_open_count++;
264 uart_port_unlock_irqrestore(port, lock_flags);
265
266 jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n");
267 return 0;
268}
269
270static void jsm_tty_close(struct uart_port *port)
271{
272 struct jsm_board *bd;
273 struct jsm_channel *channel =
274 container_of(port, struct jsm_channel, uart_port);
275
276 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "start\n");
277
278 bd = channel->ch_bd;
279
280 channel->ch_flags &= ~(CH_STOPI);
281
282 channel->ch_open_count--;
283
284 /*
285 * If we have HUPCL set, lower DTR and RTS
286 */
287 if (channel->ch_c_cflag & HUPCL) {
288 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev,
289 "Close. HUPCL set, dropping DTR/RTS\n");
290
291 /* Drop RTS/DTR */
292 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
293 bd->bd_ops->assert_modem_signals(channel);
294 }
295
296 /* Turn off UART interrupts for this port */
297 channel->ch_bd->bd_ops->uart_off(channel);
298
299 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "finish\n");
300}
301
302static void jsm_tty_set_termios(struct uart_port *port,
303 struct ktermios *termios,
304 const struct ktermios *old_termios)
305{
306 unsigned long lock_flags;
307 struct jsm_channel *channel =
308 container_of(port, struct jsm_channel, uart_port);
309
310 uart_port_lock_irqsave(port, &lock_flags);
311 channel->ch_c_cflag = termios->c_cflag;
312 channel->ch_c_iflag = termios->c_iflag;
313 channel->ch_c_oflag = termios->c_oflag;
314 channel->ch_c_lflag = termios->c_lflag;
315 channel->ch_startc = termios->c_cc[VSTART];
316 channel->ch_stopc = termios->c_cc[VSTOP];
317
318 channel->ch_bd->bd_ops->param(channel);
319 jsm_carrier(channel);
320 uart_port_unlock_irqrestore(port, lock_flags);
321}
322
323static const char *jsm_tty_type(struct uart_port *port)
324{
325 return "jsm";
326}
327
328static void jsm_tty_release_port(struct uart_port *port)
329{
330}
331
332static int jsm_tty_request_port(struct uart_port *port)
333{
334 return 0;
335}
336
337static void jsm_config_port(struct uart_port *port, int flags)
338{
339 port->type = PORT_JSM;
340}
341
342static const struct uart_ops jsm_ops = {
343 .tx_empty = jsm_tty_tx_empty,
344 .set_mctrl = jsm_tty_set_mctrl,
345 .get_mctrl = jsm_tty_get_mctrl,
346 .stop_tx = jsm_tty_stop_tx,
347 .start_tx = jsm_tty_start_tx,
348 .send_xchar = jsm_tty_send_xchar,
349 .stop_rx = jsm_tty_stop_rx,
350 .break_ctl = jsm_tty_break,
351 .startup = jsm_tty_open,
352 .shutdown = jsm_tty_close,
353 .set_termios = jsm_tty_set_termios,
354 .type = jsm_tty_type,
355 .release_port = jsm_tty_release_port,
356 .request_port = jsm_tty_request_port,
357 .config_port = jsm_config_port,
358};
359
360/*
361 * jsm_tty_init()
362 *
363 * Init the tty subsystem. Called once per board after board has been
364 * downloaded and init'ed.
365 */
366int jsm_tty_init(struct jsm_board *brd)
367{
368 int i;
369 void __iomem *vaddr;
370 struct jsm_channel *ch;
371
372 if (!brd)
373 return -ENXIO;
374
375 jsm_dbg(INIT, &brd->pci_dev, "start\n");
376
377 /*
378 * Initialize board structure elements.
379 */
380
381 brd->nasync = brd->maxports;
382
383 /*
384 * Allocate channel memory that might not have been allocated
385 * when the driver was first loaded.
386 */
387 for (i = 0; i < brd->nasync; i++) {
388 if (!brd->channels[i]) {
389
390 /*
391 * Okay to malloc with GFP_KERNEL, we are not at
392 * interrupt context, and there are no locks held.
393 */
394 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
395 if (!brd->channels[i]) {
396 jsm_dbg(CORE, &brd->pci_dev,
397 "%s:%d Unable to allocate memory for channel struct\n",
398 __FILE__, __LINE__);
399 }
400 }
401 }
402
403 ch = brd->channels[0];
404 vaddr = brd->re_map_membase;
405
406 /* Set up channel variables */
407 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
408
409 if (!brd->channels[i])
410 continue;
411
412 spin_lock_init(&ch->ch_lock);
413
414 if (brd->bd_uart_offset == 0x200)
415 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i);
416 else
417 ch->ch_cls_uart = vaddr + (brd->bd_uart_offset * i);
418
419 ch->ch_bd = brd;
420 ch->ch_portnum = i;
421
422 /* .25 second delay */
423 ch->ch_close_delay = 250;
424
425 init_waitqueue_head(&ch->ch_flags_wait);
426 }
427
428 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
429 return 0;
430}
431
432int jsm_uart_port_init(struct jsm_board *brd)
433{
434 int i, rc;
435 unsigned int line;
436
437 if (!brd)
438 return -ENXIO;
439
440 jsm_dbg(INIT, &brd->pci_dev, "start\n");
441
442 /*
443 * Initialize board structure elements.
444 */
445
446 brd->nasync = brd->maxports;
447
448 /* Set up channel variables */
449 for (i = 0; i < brd->nasync; i++) {
450
451 if (!brd->channels[i])
452 continue;
453
454 brd->channels[i]->uart_port.irq = brd->irq;
455 brd->channels[i]->uart_port.uartclk = 14745600;
456 brd->channels[i]->uart_port.type = PORT_JSM;
457 brd->channels[i]->uart_port.iotype = UPIO_MEM;
458 brd->channels[i]->uart_port.membase = brd->re_map_membase;
459 brd->channels[i]->uart_port.fifosize = 16;
460 brd->channels[i]->uart_port.ops = &jsm_ops;
461 line = find_first_zero_bit(linemap, MAXLINES);
462 if (line >= MAXLINES) {
463 printk(KERN_INFO "jsm: linemap is full, added device failed\n");
464 continue;
465 } else
466 set_bit(line, linemap);
467 brd->channels[i]->uart_port.line = line;
468 rc = uart_add_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
469 if (rc) {
470 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
471 return rc;
472 } else
473 printk(KERN_INFO "jsm: Port %d added\n", i);
474 }
475
476 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
477 return 0;
478}
479
480int jsm_remove_uart_port(struct jsm_board *brd)
481{
482 int i;
483 struct jsm_channel *ch;
484
485 if (!brd)
486 return -ENXIO;
487
488 jsm_dbg(INIT, &brd->pci_dev, "start\n");
489
490 /*
491 * Initialize board structure elements.
492 */
493
494 brd->nasync = brd->maxports;
495
496 /* Set up channel variables */
497 for (i = 0; i < brd->nasync; i++) {
498
499 if (!brd->channels[i])
500 continue;
501
502 ch = brd->channels[i];
503
504 clear_bit(ch->uart_port.line, linemap);
505 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
506 }
507
508 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
509 return 0;
510}
511
512void jsm_input(struct jsm_channel *ch)
513{
514 struct jsm_board *bd;
515 struct tty_struct *tp;
516 struct tty_port *port;
517 u32 rmask;
518 u16 head;
519 u16 tail;
520 int data_len;
521 unsigned long lock_flags;
522 int len = 0;
523 int s = 0;
524 int i = 0;
525
526 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
527
528 port = &ch->uart_port.state->port;
529 tp = port->tty;
530
531 bd = ch->ch_bd;
532 if (!bd)
533 return;
534
535 spin_lock_irqsave(&ch->ch_lock, lock_flags);
536
537 /*
538 *Figure the number of characters in the buffer.
539 *Exit immediately if none.
540 */
541
542 rmask = RQUEUEMASK;
543
544 head = ch->ch_r_head & rmask;
545 tail = ch->ch_r_tail & rmask;
546
547 data_len = (head - tail) & rmask;
548 if (data_len == 0) {
549 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
550 return;
551 }
552
553 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
554
555 /*
556 *If the device is not open, or CREAD is off, flush
557 *input data and return immediately.
558 */
559 if (!tp || !C_CREAD(tp)) {
560
561 jsm_dbg(READ, &ch->ch_bd->pci_dev,
562 "input. dropping %d bytes on port %d...\n",
563 data_len, ch->ch_portnum);
564 ch->ch_r_head = tail;
565
566 /* Force queue flow control to be released, if needed */
567 jsm_check_queue_flow_control(ch);
568
569 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
570 return;
571 }
572
573 /*
574 * If we are throttled, simply don't read any data.
575 */
576 if (ch->ch_flags & CH_STOPI) {
577 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
578 jsm_dbg(READ, &ch->ch_bd->pci_dev,
579 "Port %d throttled, not reading any data. head: %x tail: %x\n",
580 ch->ch_portnum, head, tail);
581 return;
582 }
583
584 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n");
585
586 len = tty_buffer_request_room(port, data_len);
587
588 /*
589 * len now contains the most amount of data we can copy,
590 * bounded either by the flip buffer size or the amount
591 * of data the card actually has pending...
592 */
593 while (len) {
594 s = ((head >= tail) ? head : RQUEUESIZE) - tail;
595 s = min(s, len);
596
597 if (s <= 0)
598 break;
599
600 /*
601 * If conditions are such that ld needs to see all
602 * UART errors, we will have to walk each character
603 * and error byte and send them to the buffer one at
604 * a time.
605 */
606
607 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
608 for (i = 0; i < s; i++) {
609 u8 chr = ch->ch_rqueue[tail + i];
610 u8 error = ch->ch_equeue[tail + i];
611 char flag = TTY_NORMAL;
612
613 /*
614 * Give the Linux ld the flags in the format it
615 * likes.
616 */
617 if (error & UART_LSR_BI)
618 flag = TTY_BREAK;
619 else if (error & UART_LSR_PE)
620 flag = TTY_PARITY;
621 else if (error & UART_LSR_FE)
622 flag = TTY_FRAME;
623
624 tty_insert_flip_char(port, chr, flag);
625 }
626 } else {
627 tty_insert_flip_string(port, ch->ch_rqueue + tail, s);
628 }
629 tail += s;
630 len -= s;
631 /* Flip queue if needed */
632 tail &= rmask;
633 }
634
635 ch->ch_r_tail = tail & rmask;
636 ch->ch_e_tail = tail & rmask;
637 jsm_check_queue_flow_control(ch);
638 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
639
640 /* Tell the tty layer its okay to "eat" the data now */
641 tty_flip_buffer_push(port);
642
643 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
644}
645
646static void jsm_carrier(struct jsm_channel *ch)
647{
648 struct jsm_board *bd;
649
650 int virt_carrier = 0;
651 int phys_carrier = 0;
652
653 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "start\n");
654
655 bd = ch->ch_bd;
656 if (!bd)
657 return;
658
659 if (ch->ch_mistat & UART_MSR_DCD) {
660 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "mistat: %x D_CD: %x\n",
661 ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
662 phys_carrier = 1;
663 }
664
665 if (ch->ch_c_cflag & CLOCAL)
666 virt_carrier = 1;
667
668 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "DCD: physical: %d virt: %d\n",
669 phys_carrier, virt_carrier);
670
671 /*
672 * Test for a VIRTUAL carrier transition to HIGH.
673 */
674 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
675
676 /*
677 * When carrier rises, wake any threads waiting
678 * for carrier in the open routine.
679 */
680
681 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "carrier: virt DCD rose\n");
682
683 if (waitqueue_active(&(ch->ch_flags_wait)))
684 wake_up_interruptible(&ch->ch_flags_wait);
685 }
686
687 /*
688 * Test for a PHYSICAL carrier transition to HIGH.
689 */
690 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
691
692 /*
693 * When carrier rises, wake any threads waiting
694 * for carrier in the open routine.
695 */
696
697 jsm_dbg(CARR, &ch->ch_bd->pci_dev,
698 "carrier: physical DCD rose\n");
699
700 if (waitqueue_active(&(ch->ch_flags_wait)))
701 wake_up_interruptible(&ch->ch_flags_wait);
702 }
703
704 /*
705 * Test for a PHYSICAL transition to low, so long as we aren't
706 * currently ignoring physical transitions (which is what "virtual
707 * carrier" indicates).
708 *
709 * The transition of the virtual carrier to low really doesn't
710 * matter... it really only means "ignore carrier state", not
711 * "make pretend that carrier is there".
712 */
713 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
714 && (phys_carrier == 0)) {
715 /*
716 * When carrier drops:
717 *
718 * Drop carrier on all open units.
719 *
720 * Flush queues, waking up any task waiting in the
721 * line discipline.
722 *
723 * Send a hangup to the control terminal.
724 *
725 * Enable all select calls.
726 */
727 if (waitqueue_active(&(ch->ch_flags_wait)))
728 wake_up_interruptible(&ch->ch_flags_wait);
729 }
730
731 /*
732 * Make sure that our cached values reflect the current reality.
733 */
734 if (virt_carrier == 1)
735 ch->ch_flags |= CH_FCAR;
736 else
737 ch->ch_flags &= ~CH_FCAR;
738
739 if (phys_carrier == 1)
740 ch->ch_flags |= CH_CD;
741 else
742 ch->ch_flags &= ~CH_CD;
743}
744
745
746void jsm_check_queue_flow_control(struct jsm_channel *ch)
747{
748 struct board_ops *bd_ops = ch->ch_bd->bd_ops;
749 int qleft;
750
751 /* Store how much space we have left in the queue */
752 qleft = ch->ch_r_tail - ch->ch_r_head - 1;
753 if (qleft < 0)
754 qleft += RQUEUEMASK + 1;
755
756 /*
757 * Check to see if we should enforce flow control on our queue because
758 * the ld (or user) isn't reading data out of our queue fast enuf.
759 *
760 * NOTE: This is done based on what the current flow control of the
761 * port is set for.
762 *
763 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
764 * This will cause the UART's FIFO to back up, and force
765 * the RTS signal to be dropped.
766 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
767 * the other side, in hopes it will stop sending data to us.
768 * 3) NONE - Nothing we can do. We will simply drop any extra data
769 * that gets sent into us when the queue fills up.
770 */
771 if (qleft < 256) {
772 /* HWFLOW */
773 if (ch->ch_c_cflag & CRTSCTS) {
774 if (!(ch->ch_flags & CH_RECEIVER_OFF)) {
775 bd_ops->disable_receiver(ch);
776 ch->ch_flags |= (CH_RECEIVER_OFF);
777 jsm_dbg(READ, &ch->ch_bd->pci_dev,
778 "Internal queue hit hilevel mark (%d)! Turning off interrupts\n",
779 qleft);
780 }
781 }
782 /* SWFLOW */
783 else if (ch->ch_c_iflag & IXOFF) {
784 if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
785 bd_ops->send_stop_character(ch);
786 ch->ch_stops_sent++;
787 jsm_dbg(READ, &ch->ch_bd->pci_dev,
788 "Sending stop char! Times sent: %x\n",
789 ch->ch_stops_sent);
790 }
791 }
792 }
793
794 /*
795 * Check to see if we should unenforce flow control because
796 * ld (or user) finally read enuf data out of our queue.
797 *
798 * NOTE: This is done based on what the current flow control of the
799 * port is set for.
800 *
801 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
802 * This will cause the UART's FIFO to raise RTS back up,
803 * which will allow the other side to start sending data again.
804 * 2) SWFLOW (IXOFF) - Send a start character to
805 * the other side, so it will start sending data to us again.
806 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
807 * other side, we don't need to do anything now.
808 */
809 if (qleft > (RQUEUESIZE / 2)) {
810 /* HWFLOW */
811 if (ch->ch_c_cflag & CRTSCTS) {
812 if (ch->ch_flags & CH_RECEIVER_OFF) {
813 bd_ops->enable_receiver(ch);
814 ch->ch_flags &= ~(CH_RECEIVER_OFF);
815 jsm_dbg(READ, &ch->ch_bd->pci_dev,
816 "Internal queue hit lowlevel mark (%d)! Turning on interrupts\n",
817 qleft);
818 }
819 }
820 /* SWFLOW */
821 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
822 ch->ch_stops_sent = 0;
823 bd_ops->send_start_character(ch);
824 jsm_dbg(READ, &ch->ch_bd->pci_dev,
825 "Sending start char!\n");
826 }
827 }
828}