1 /*
2 * Copyright 2003 Digi International (www.digi.com)
3 * Scott H Kilau <Scott_Kilau at digi dot com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2, or (at your option)
8 * any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
13 * PURPOSE. See the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 *
19 *
20 * NOTE TO LINUX KERNEL HACKERS: DO NOT REFORMAT THIS CODE!
21 *
22 * This is shared code between Digi's CVS archive and the
23 * Linux Kernel sources.
24 * Changing the source just for reformatting needlessly breaks
25 * our CVS diff history.
26 *
27 * Send any bug fixes/changes to: Eng.Linux at digi dot com.
28 * Thank you.
29 *
30 */
31
32 #include <linux/kernel.h>
33 #include <linux/sched.h> /* For jiffies, task states */
34 #include <linux/interrupt.h> /* For tasklet and interrupt structs/defines */
35 #include <linux/delay.h> /* For udelay */
36 #include <linux/io.h> /* For read[bwl]/write[bwl] */
37 #include <linux/serial.h> /* For struct async_serial */
38 #include <linux/serial_reg.h> /* For the various UART offsets */
39 #include <linux/pci.h>
40
41 #include "dgnc_driver.h" /* Driver main header file */
42 #include "dgnc_cls.h"
43 #include "dgnc_tty.h"
44
45 static inline void cls_parse_isr(struct dgnc_board *brd, uint port);
46 static inline void cls_clear_break(struct channel_t *ch, int force);
47 static inline void cls_set_cts_flow_control(struct channel_t *ch);
48 static inline void cls_set_rts_flow_control(struct channel_t *ch);
49 static inline void cls_set_ixon_flow_control(struct channel_t *ch);
50 static inline void cls_set_ixoff_flow_control(struct channel_t *ch);
51 static inline void cls_set_no_output_flow_control(struct channel_t *ch);
52 static inline void cls_set_no_input_flow_control(struct channel_t *ch);
53 static void cls_parse_modem(struct channel_t *ch, unsigned char signals);
54 static void cls_tasklet(unsigned long data);
55 static void cls_vpd(struct dgnc_board *brd);
56 static void cls_uart_init(struct channel_t *ch);
57 static void cls_uart_off(struct channel_t *ch);
58 static int cls_drain(struct tty_struct *tty, uint seconds);
59 static void cls_param(struct tty_struct *tty);
60 static void cls_assert_modem_signals(struct channel_t *ch);
61 static void cls_flush_uart_write(struct channel_t *ch);
62 static void cls_flush_uart_read(struct channel_t *ch);
63 static void cls_disable_receiver(struct channel_t *ch);
64 static void cls_enable_receiver(struct channel_t *ch);
65 static void cls_send_break(struct channel_t *ch, int msecs);
66 static void cls_send_start_character(struct channel_t *ch);
67 static void cls_send_stop_character(struct channel_t *ch);
68 static void cls_copy_data_from_uart_to_queue(struct channel_t *ch);
69 static void cls_copy_data_from_queue_to_uart(struct channel_t *ch);
70 static uint cls_get_uart_bytes_left(struct channel_t *ch);
71 static void cls_send_immediate_char(struct channel_t *ch, unsigned char);
72 static irqreturn_t cls_intr(int irq, void *voidbrd);
73
74 struct board_ops dgnc_cls_ops = {
75 .tasklet = cls_tasklet,
76 .intr = cls_intr,
77 .uart_init = cls_uart_init,
78 .uart_off = cls_uart_off,
79 .drain = cls_drain,
80 .param = cls_param,
81 .vpd = cls_vpd,
82 .assert_modem_signals = cls_assert_modem_signals,
83 .flush_uart_write = cls_flush_uart_write,
84 .flush_uart_read = cls_flush_uart_read,
85 .disable_receiver = cls_disable_receiver,
86 .enable_receiver = cls_enable_receiver,
87 .send_break = cls_send_break,
88 .send_start_character = cls_send_start_character,
89 .send_stop_character = cls_send_stop_character,
90 .copy_data_from_queue_to_uart = cls_copy_data_from_queue_to_uart,
91 .get_uart_bytes_left = cls_get_uart_bytes_left,
92 .send_immediate_char = cls_send_immediate_char
93 };
94
95
cls_set_cts_flow_control(struct channel_t * ch)96 static inline void cls_set_cts_flow_control(struct channel_t *ch)
97 {
98 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
99 unsigned char ier = readb(&ch->ch_cls_uart->ier);
100 unsigned char isr_fcr = 0;
101
102
103 /*
104 * The Enhanced Register Set may only be accessed when
105 * the Line Control Register is set to 0xBFh.
106 */
107 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
108
109 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
110
111 /* Turn on CTS flow control, turn off IXON flow control */
112 isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_CTSDSR);
113 isr_fcr &= ~(UART_EXAR654_EFR_IXON);
114
115 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
116
117 /* Write old LCR value back out, which turns enhanced access off */
118 writeb(lcrb, &ch->ch_cls_uart->lcr);
119
120 /*
121 * Enable interrupts for CTS flow, turn off interrupts for
122 * received XOFF chars
123 */
124 ier |= (UART_EXAR654_IER_CTSDSR);
125 ier &= ~(UART_EXAR654_IER_XOFF);
126 writeb(ier, &ch->ch_cls_uart->ier);
127
128 /* Set the usual FIFO values */
129 writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
130
131 writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_56 |
132 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
133 &ch->ch_cls_uart->isr_fcr);
134
135 ch->ch_t_tlevel = 16;
136
137 }
138
139
cls_set_ixon_flow_control(struct channel_t * ch)140 static inline void cls_set_ixon_flow_control(struct channel_t *ch)
141 {
142 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
143 unsigned char ier = readb(&ch->ch_cls_uart->ier);
144 unsigned char isr_fcr = 0;
145
146
147 /*
148 * The Enhanced Register Set may only be accessed when
149 * the Line Control Register is set to 0xBFh.
150 */
151 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
152
153 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
154
155 /* Turn on IXON flow control, turn off CTS flow control */
156 isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_IXON);
157 isr_fcr &= ~(UART_EXAR654_EFR_CTSDSR);
158
159 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
160
161 /* Now set our current start/stop chars while in enhanced mode */
162 writeb(ch->ch_startc, &ch->ch_cls_uart->mcr);
163 writeb(0, &ch->ch_cls_uart->lsr);
164 writeb(ch->ch_stopc, &ch->ch_cls_uart->msr);
165 writeb(0, &ch->ch_cls_uart->spr);
166
167 /* Write old LCR value back out, which turns enhanced access off */
168 writeb(lcrb, &ch->ch_cls_uart->lcr);
169
170 /*
171 * Disable interrupts for CTS flow, turn on interrupts for
172 * received XOFF chars
173 */
174 ier &= ~(UART_EXAR654_IER_CTSDSR);
175 ier |= (UART_EXAR654_IER_XOFF);
176 writeb(ier, &ch->ch_cls_uart->ier);
177
178 /* Set the usual FIFO values */
179 writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
180
181 writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
182 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
183 &ch->ch_cls_uart->isr_fcr);
184
185 }
186
187
cls_set_no_output_flow_control(struct channel_t * ch)188 static inline void cls_set_no_output_flow_control(struct channel_t *ch)
189 {
190 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
191 unsigned char ier = readb(&ch->ch_cls_uart->ier);
192 unsigned char isr_fcr = 0;
193
194
195 /*
196 * The Enhanced Register Set may only be accessed when
197 * the Line Control Register is set to 0xBFh.
198 */
199 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
200
201 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
202
203 /* Turn off IXON flow control, turn off CTS flow control */
204 isr_fcr |= (UART_EXAR654_EFR_ECB);
205 isr_fcr &= ~(UART_EXAR654_EFR_CTSDSR | UART_EXAR654_EFR_IXON);
206
207 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
208
209 /* Write old LCR value back out, which turns enhanced access off */
210 writeb(lcrb, &ch->ch_cls_uart->lcr);
211
212 /*
213 * Disable interrupts for CTS flow, turn off interrupts for
214 * received XOFF chars
215 */
216 ier &= ~(UART_EXAR654_IER_CTSDSR);
217 ier &= ~(UART_EXAR654_IER_XOFF);
218 writeb(ier, &ch->ch_cls_uart->ier);
219
220 /* Set the usual FIFO values */
221 writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
222
223 writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
224 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
225 &ch->ch_cls_uart->isr_fcr);
226
227 ch->ch_r_watermark = 0;
228 ch->ch_t_tlevel = 16;
229 ch->ch_r_tlevel = 16;
230
231 }
232
233
cls_set_rts_flow_control(struct channel_t * ch)234 static inline void cls_set_rts_flow_control(struct channel_t *ch)
235 {
236 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
237 unsigned char ier = readb(&ch->ch_cls_uart->ier);
238 unsigned char isr_fcr = 0;
239
240
241 /*
242 * The Enhanced Register Set may only be accessed when
243 * the Line Control Register is set to 0xBFh.
244 */
245 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
246
247 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
248
249 /* Turn on RTS flow control, turn off IXOFF flow control */
250 isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_RTSDTR);
251 isr_fcr &= ~(UART_EXAR654_EFR_IXOFF);
252
253 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
254
255 /* Write old LCR value back out, which turns enhanced access off */
256 writeb(lcrb, &ch->ch_cls_uart->lcr);
257
258 /* Enable interrupts for RTS flow */
259 ier |= (UART_EXAR654_IER_RTSDTR);
260 writeb(ier, &ch->ch_cls_uart->ier);
261
262 /* Set the usual FIFO values */
263 writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
264
265 writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_56 |
266 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
267 &ch->ch_cls_uart->isr_fcr);
268
269
270 ch->ch_r_watermark = 4;
271 ch->ch_r_tlevel = 8;
272
273 }
274
275
cls_set_ixoff_flow_control(struct channel_t * ch)276 static inline void cls_set_ixoff_flow_control(struct channel_t *ch)
277 {
278 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
279 unsigned char ier = readb(&ch->ch_cls_uart->ier);
280 unsigned char isr_fcr = 0;
281
282
283 /*
284 * The Enhanced Register Set may only be accessed when
285 * the Line Control Register is set to 0xBFh.
286 */
287 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
288
289 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
290
291 /* Turn on IXOFF flow control, turn off RTS flow control */
292 isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_IXOFF);
293 isr_fcr &= ~(UART_EXAR654_EFR_RTSDTR);
294
295 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
296
297 /* Now set our current start/stop chars while in enhanced mode */
298 writeb(ch->ch_startc, &ch->ch_cls_uart->mcr);
299 writeb(0, &ch->ch_cls_uart->lsr);
300 writeb(ch->ch_stopc, &ch->ch_cls_uart->msr);
301 writeb(0, &ch->ch_cls_uart->spr);
302
303 /* Write old LCR value back out, which turns enhanced access off */
304 writeb(lcrb, &ch->ch_cls_uart->lcr);
305
306 /* Disable interrupts for RTS flow */
307 ier &= ~(UART_EXAR654_IER_RTSDTR);
308 writeb(ier, &ch->ch_cls_uart->ier);
309
310 /* Set the usual FIFO values */
311 writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
312
313 writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
314 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
315 &ch->ch_cls_uart->isr_fcr);
316
317 }
318
319
cls_set_no_input_flow_control(struct channel_t * ch)320 static inline void cls_set_no_input_flow_control(struct channel_t *ch)
321 {
322 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
323 unsigned char ier = readb(&ch->ch_cls_uart->ier);
324 unsigned char isr_fcr = 0;
325
326
327 /*
328 * The Enhanced Register Set may only be accessed when
329 * the Line Control Register is set to 0xBFh.
330 */
331 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
332
333 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
334
335 /* Turn off IXOFF flow control, turn off RTS flow control */
336 isr_fcr |= (UART_EXAR654_EFR_ECB);
337 isr_fcr &= ~(UART_EXAR654_EFR_RTSDTR | UART_EXAR654_EFR_IXOFF);
338
339 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
340
341 /* Write old LCR value back out, which turns enhanced access off */
342 writeb(lcrb, &ch->ch_cls_uart->lcr);
343
344 /* Disable interrupts for RTS flow */
345 ier &= ~(UART_EXAR654_IER_RTSDTR);
346 writeb(ier, &ch->ch_cls_uart->ier);
347
348 /* Set the usual FIFO values */
349 writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
350
351 writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
352 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
353 &ch->ch_cls_uart->isr_fcr);
354
355 ch->ch_t_tlevel = 16;
356 ch->ch_r_tlevel = 16;
357
358 }
359
360
361 /*
362 * cls_clear_break.
363 * Determines whether its time to shut off break condition.
364 *
365 * No locks are assumed to be held when calling this function.
366 * channel lock is held and released in this function.
367 */
cls_clear_break(struct channel_t * ch,int force)368 static inline void cls_clear_break(struct channel_t *ch, int force)
369 {
370 unsigned long flags;
371
372 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
373 return;
374
375 spin_lock_irqsave(&ch->ch_lock, flags);
376
377 /* Bail if we aren't currently sending a break. */
378 if (!ch->ch_stop_sending_break) {
379 spin_unlock_irqrestore(&ch->ch_lock, flags);
380 return;
381 }
382
383 /* Turn break off, and unset some variables */
384 if (ch->ch_flags & CH_BREAK_SENDING) {
385 if (time_after(jiffies, ch->ch_stop_sending_break) || force) {
386 unsigned char temp = readb(&ch->ch_cls_uart->lcr);
387
388 writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
389 ch->ch_flags &= ~(CH_BREAK_SENDING);
390 ch->ch_stop_sending_break = 0;
391 }
392 }
393 spin_unlock_irqrestore(&ch->ch_lock, flags);
394 }
395
396
397 /* Parse the ISR register for the specific port */
cls_parse_isr(struct dgnc_board * brd,uint port)398 static inline void cls_parse_isr(struct dgnc_board *brd, uint port)
399 {
400 struct channel_t *ch;
401 unsigned char isr = 0;
402 unsigned long flags;
403
404 /*
405 * No need to verify board pointer, it was already
406 * verified in the interrupt routine.
407 */
408
409 if (port > brd->nasync)
410 return;
411
412 ch = brd->channels[port];
413 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
414 return;
415
416 /* Here we try to figure out what caused the interrupt to happen */
417 while (1) {
418
419 isr = readb(&ch->ch_cls_uart->isr_fcr);
420
421 /* Bail if no pending interrupt on port */
422 if (isr & UART_IIR_NO_INT)
423 break;
424
425 /* Receive Interrupt pending */
426 if (isr & (UART_IIR_RDI | UART_IIR_RDI_TIMEOUT)) {
427 /* Read data from uart -> queue */
428 brd->intr_rx++;
429 ch->ch_intr_rx++;
430 cls_copy_data_from_uart_to_queue(ch);
431 dgnc_check_queue_flow_control(ch);
432 }
433
434 /* Transmit Hold register empty pending */
435 if (isr & UART_IIR_THRI) {
436 /* Transfer data (if any) from Write Queue -> UART. */
437 spin_lock_irqsave(&ch->ch_lock, flags);
438 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
439 brd->intr_tx++;
440 ch->ch_intr_tx++;
441 spin_unlock_irqrestore(&ch->ch_lock, flags);
442 cls_copy_data_from_queue_to_uart(ch);
443 }
444
445 /* CTS/RTS change of state */
446 if (isr & UART_IIR_CTSRTS) {
447 brd->intr_modem++;
448 ch->ch_intr_modem++;
449 /*
450 * Don't need to do anything, the cls_parse_modem
451 * below will grab the updated modem signals.
452 */
453 }
454
455 /* Parse any modem signal changes */
456 cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));
457 }
458 }
459
460
461 /*
462 * cls_param()
463 * Send any/all changes to the line to the UART.
464 */
cls_param(struct tty_struct * tty)465 static void cls_param(struct tty_struct *tty)
466 {
467 unsigned char lcr = 0;
468 unsigned char uart_lcr = 0;
469 unsigned char ier = 0;
470 unsigned char uart_ier = 0;
471 uint baud = 9600;
472 int quot = 0;
473 struct dgnc_board *bd;
474 struct channel_t *ch;
475 struct un_t *un;
476
477 if (!tty || tty->magic != TTY_MAGIC)
478 return;
479
480 un = (struct un_t *) tty->driver_data;
481 if (!un || un->magic != DGNC_UNIT_MAGIC)
482 return;
483
484 ch = un->un_ch;
485 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
486 return;
487
488 bd = ch->ch_bd;
489 if (!bd || bd->magic != DGNC_BOARD_MAGIC)
490 return;
491
492 /*
493 * If baud rate is zero, flush queues, and set mval to drop DTR.
494 */
495 if ((ch->ch_c_cflag & (CBAUD)) == 0) {
496 ch->ch_r_head = 0;
497 ch->ch_r_tail = 0;
498 ch->ch_e_head = 0;
499 ch->ch_e_tail = 0;
500 ch->ch_w_head = 0;
501 ch->ch_w_tail = 0;
502
503 cls_flush_uart_write(ch);
504 cls_flush_uart_read(ch);
505
506 /* The baudrate is B0 so all modem lines are to be dropped. */
507 ch->ch_flags |= (CH_BAUD0);
508 ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
509 cls_assert_modem_signals(ch);
510 ch->ch_old_baud = 0;
511 return;
512 } else if (ch->ch_custom_speed) {
513
514 baud = ch->ch_custom_speed;
515 /* Handle transition from B0 */
516 if (ch->ch_flags & CH_BAUD0) {
517 ch->ch_flags &= ~(CH_BAUD0);
518
519 /*
520 * Bring back up RTS and DTR...
521 * Also handle RTS or DTR toggle if set.
522 */
523 if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))
524 ch->ch_mostat |= (UART_MCR_RTS);
525 if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))
526 ch->ch_mostat |= (UART_MCR_DTR);
527 }
528
529 } else {
530 int iindex = 0;
531 int jindex = 0;
532
533 ulong bauds[4][16] = {
534 { /* slowbaud */
535 0, 50, 75, 110,
536 134, 150, 200, 300,
537 600, 1200, 1800, 2400,
538 4800, 9600, 19200, 38400 },
539 { /* slowbaud & CBAUDEX */
540 0, 57600, 115200, 230400,
541 460800, 150, 200, 921600,
542 600, 1200, 1800, 2400,
543 4800, 9600, 19200, 38400 },
544 { /* fastbaud */
545 0, 57600, 76800, 115200,
546 131657, 153600, 230400, 460800,
547 921600, 1200, 1800, 2400,
548 4800, 9600, 19200, 38400 },
549 { /* fastbaud & CBAUDEX */
550 0, 57600, 115200, 230400,
551 460800, 150, 200, 921600,
552 600, 1200, 1800, 2400,
553 4800, 9600, 19200, 38400 }
554 };
555
556 /*
557 * Only use the TXPrint baud rate if the terminal
558 * unit is NOT open
559 */
560 if (!(ch->ch_tun.un_flags & UN_ISOPEN) &&
561 (un->un_type == DGNC_PRINT))
562 baud = C_BAUD(ch->ch_pun.un_tty) & 0xff;
563 else
564 baud = C_BAUD(ch->ch_tun.un_tty) & 0xff;
565
566 if (ch->ch_c_cflag & CBAUDEX)
567 iindex = 1;
568
569 if (ch->ch_digi.digi_flags & DIGI_FAST)
570 iindex += 2;
571
572 jindex = baud;
573
574 if ((iindex >= 0) && (iindex < 4) && (jindex >= 0) &&
575 (jindex < 16)) {
576 baud = bauds[iindex][jindex];
577 } else {
578 baud = 0;
579 }
580
581 if (baud == 0)
582 baud = 9600;
583
584 /* Handle transition from B0 */
585 if (ch->ch_flags & CH_BAUD0) {
586 ch->ch_flags &= ~(CH_BAUD0);
587
588 /*
589 * Bring back up RTS and DTR...
590 * Also handle RTS or DTR toggle if set.
591 */
592 if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))
593 ch->ch_mostat |= (UART_MCR_RTS);
594 if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))
595 ch->ch_mostat |= (UART_MCR_DTR);
596 }
597 }
598
599 if (ch->ch_c_cflag & PARENB)
600 lcr |= UART_LCR_PARITY;
601
602 if (!(ch->ch_c_cflag & PARODD))
603 lcr |= UART_LCR_EPAR;
604
605 /*
606 * Not all platforms support mark/space parity,
607 * so this will hide behind an ifdef.
608 */
609 #ifdef CMSPAR
610 if (ch->ch_c_cflag & CMSPAR)
611 lcr |= UART_LCR_SPAR;
612 #endif
613
614 if (ch->ch_c_cflag & CSTOPB)
615 lcr |= UART_LCR_STOP;
616
617 switch (ch->ch_c_cflag & CSIZE) {
618 case CS5:
619 lcr |= UART_LCR_WLEN5;
620 break;
621 case CS6:
622 lcr |= UART_LCR_WLEN6;
623 break;
624 case CS7:
625 lcr |= UART_LCR_WLEN7;
626 break;
627 case CS8:
628 default:
629 lcr |= UART_LCR_WLEN8;
630 break;
631 }
632
633 uart_ier = readb(&ch->ch_cls_uart->ier);
634 ier = uart_ier;
635 uart_lcr = readb(&ch->ch_cls_uart->lcr);
636
637 if (baud == 0)
638 baud = 9600;
639
640 quot = ch->ch_bd->bd_dividend / baud;
641
642 if (quot != 0 && ch->ch_old_baud != baud) {
643 ch->ch_old_baud = baud;
644 writeb(UART_LCR_DLAB, &ch->ch_cls_uart->lcr);
645 writeb((quot & 0xff), &ch->ch_cls_uart->txrx);
646 writeb((quot >> 8), &ch->ch_cls_uart->ier);
647 writeb(lcr, &ch->ch_cls_uart->lcr);
648 }
649
650 if (uart_lcr != lcr)
651 writeb(lcr, &ch->ch_cls_uart->lcr);
652
653 if (ch->ch_c_cflag & CREAD)
654 ier |= (UART_IER_RDI | UART_IER_RLSI);
655 else
656 ier &= ~(UART_IER_RDI | UART_IER_RLSI);
657
658 /*
659 * Have the UART interrupt on modem signal changes ONLY when
660 * we are in hardware flow control mode, or CLOCAL/FORCEDCD is not set.
661 */
662 if ((ch->ch_digi.digi_flags & CTSPACE) ||
663 (ch->ch_digi.digi_flags & RTSPACE) ||
664 (ch->ch_c_cflag & CRTSCTS) ||
665 !(ch->ch_digi.digi_flags & DIGI_FORCEDCD) ||
666 !(ch->ch_c_cflag & CLOCAL))
667 ier |= UART_IER_MSI;
668 else
669 ier &= ~UART_IER_MSI;
670
671 ier |= UART_IER_THRI;
672
673 if (ier != uart_ier)
674 writeb(ier, &ch->ch_cls_uart->ier);
675
676 if (ch->ch_digi.digi_flags & CTSPACE || ch->ch_c_cflag & CRTSCTS) {
677 cls_set_cts_flow_control(ch);
678 } else if (ch->ch_c_iflag & IXON) {
679 /*
680 * If start/stop is set to disable, then we should
681 * disable flow control
682 */
683 if ((ch->ch_startc == _POSIX_VDISABLE) ||
684 (ch->ch_stopc == _POSIX_VDISABLE))
685 cls_set_no_output_flow_control(ch);
686 else
687 cls_set_ixon_flow_control(ch);
688 } else {
689 cls_set_no_output_flow_control(ch);
690 }
691
692 if (ch->ch_digi.digi_flags & RTSPACE || ch->ch_c_cflag & CRTSCTS) {
693 cls_set_rts_flow_control(ch);
694 } else if (ch->ch_c_iflag & IXOFF) {
695 /*
696 * If start/stop is set to disable, then we should disable
697 * flow control
698 */
699 if ((ch->ch_startc == _POSIX_VDISABLE) ||
700 (ch->ch_stopc == _POSIX_VDISABLE))
701 cls_set_no_input_flow_control(ch);
702 else
703 cls_set_ixoff_flow_control(ch);
704 } else {
705 cls_set_no_input_flow_control(ch);
706 }
707
708 cls_assert_modem_signals(ch);
709
710 /* Get current status of the modem signals now */
711 cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));
712 }
713
714
715 /*
716 * Our board poller function.
717 */
cls_tasklet(unsigned long data)718 static void cls_tasklet(unsigned long data)
719 {
720 struct dgnc_board *bd = (struct dgnc_board *) data;
721 struct channel_t *ch;
722 unsigned long flags;
723 int i;
724 int state = 0;
725 int ports = 0;
726
727 if (!bd || bd->magic != DGNC_BOARD_MAGIC) {
728 APR(("poll_tasklet() - NULL or bad bd.\n"));
729 return;
730 }
731
732 /* Cache a couple board values */
733 spin_lock_irqsave(&bd->bd_lock, flags);
734 state = bd->state;
735 ports = bd->nasync;
736 spin_unlock_irqrestore(&bd->bd_lock, flags);
737
738 /*
739 * Do NOT allow the interrupt routine to read the intr registers
740 * Until we release this lock.
741 */
742 spin_lock_irqsave(&bd->bd_intr_lock, flags);
743
744 /*
745 * If board is ready, parse deeper to see if there is anything to do.
746 */
747 if ((state == BOARD_READY) && (ports > 0)) {
748
749 /* Loop on each port */
750 for (i = 0; i < ports; i++) {
751 ch = bd->channels[i];
752 if (!ch)
753 continue;
754
755 /*
756 * NOTE: Remember you CANNOT hold any channel
757 * locks when calling input.
758 * During input processing, its possible we
759 * will call ld, which might do callbacks back
760 * into us.
761 */
762 dgnc_input(ch);
763
764 /*
765 * Channel lock is grabbed and then released
766 * inside this routine.
767 */
768 cls_copy_data_from_queue_to_uart(ch);
769 dgnc_wakeup_writes(ch);
770
771 /*
772 * Check carrier function.
773 */
774 dgnc_carrier(ch);
775
776 /*
777 * The timing check of turning off the break is done
778 * inside clear_break()
779 */
780 if (ch->ch_stop_sending_break)
781 cls_clear_break(ch, 0);
782 }
783 }
784
785 spin_unlock_irqrestore(&bd->bd_intr_lock, flags);
786
787 }
788
789
790 /*
791 * cls_intr()
792 *
793 * Classic specific interrupt handler.
794 */
cls_intr(int irq,void * voidbrd)795 static irqreturn_t cls_intr(int irq, void *voidbrd)
796 {
797 struct dgnc_board *brd = (struct dgnc_board *) voidbrd;
798 uint i = 0;
799 unsigned char poll_reg;
800 unsigned long flags;
801
802 if (!brd) {
803 APR(("Received interrupt (%d) with null board associated\n",
804 irq));
805 return IRQ_NONE;
806 }
807
808 /*
809 * Check to make sure its for us.
810 */
811 if (brd->magic != DGNC_BOARD_MAGIC) {
812 APR(("Received interrupt (%d) with a board pointer that wasn't ours!\n",
813 irq));
814 return IRQ_NONE;
815 }
816
817 spin_lock_irqsave(&brd->bd_intr_lock, flags);
818
819 brd->intr_count++;
820
821 /*
822 * Check the board's global interrupt offset to see if we
823 * we actually do have an interrupt pending for us.
824 */
825 poll_reg = readb(brd->re_map_membase + UART_CLASSIC_POLL_ADDR_OFFSET);
826
827 /* If 0, no interrupts pending */
828 if (!poll_reg) {
829 spin_unlock_irqrestore(&brd->bd_intr_lock, flags);
830 return IRQ_NONE;
831 }
832
833 /* Parse each port to find out what caused the interrupt */
834 for (i = 0; i < brd->nasync; i++)
835 cls_parse_isr(brd, i);
836
837 /*
838 * Schedule tasklet to more in-depth servicing at a better time.
839 */
840 tasklet_schedule(&brd->helper_tasklet);
841
842 spin_unlock_irqrestore(&brd->bd_intr_lock, flags);
843
844 return IRQ_HANDLED;
845 }
846
847
cls_disable_receiver(struct channel_t * ch)848 static void cls_disable_receiver(struct channel_t *ch)
849 {
850 unsigned char tmp = readb(&ch->ch_cls_uart->ier);
851
852 tmp &= ~(UART_IER_RDI);
853 writeb(tmp, &ch->ch_cls_uart->ier);
854 }
855
856
cls_enable_receiver(struct channel_t * ch)857 static void cls_enable_receiver(struct channel_t *ch)
858 {
859 unsigned char tmp = readb(&ch->ch_cls_uart->ier);
860
861 tmp |= (UART_IER_RDI);
862 writeb(tmp, &ch->ch_cls_uart->ier);
863 }
864
865
cls_copy_data_from_uart_to_queue(struct channel_t * ch)866 static void cls_copy_data_from_uart_to_queue(struct channel_t *ch)
867 {
868 int qleft = 0;
869 unsigned char linestatus = 0;
870 unsigned char error_mask = 0;
871 ushort head;
872 ushort tail;
873 unsigned long flags;
874
875 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
876 return;
877
878 spin_lock_irqsave(&ch->ch_lock, flags);
879
880 /* cache head and tail of queue */
881 head = ch->ch_r_head;
882 tail = ch->ch_r_tail;
883
884 /* Store how much space we have left in the queue */
885 qleft = (tail - head - 1);
886 if (qleft < 0)
887 qleft += RQUEUEMASK + 1;
888
889 /*
890 * Create a mask to determine whether we should
891 * insert the character (if any) into our queue.
892 */
893 if (ch->ch_c_iflag & IGNBRK)
894 error_mask |= UART_LSR_BI;
895
896 while (1) {
897 linestatus = readb(&ch->ch_cls_uart->lsr);
898
899 if (!(linestatus & (UART_LSR_DR)))
900 break;
901
902 /*
903 * Discard character if we are ignoring the error mask.
904 */
905 if (linestatus & error_mask) {
906 unsigned char discard;
907
908 linestatus = 0;
909 discard = readb(&ch->ch_cls_uart->txrx);
910 continue;
911 }
912
913 /*
914 * If our queue is full, we have no choice but to drop some
915 * data. The assumption is that HWFLOW or SWFLOW should have
916 * stopped things way way before we got to this point.
917 *
918 * I decided that I wanted to ditch the oldest data first,
919 * I hope thats okay with everyone? Yes? Good.
920 */
921 while (qleft < 1) {
922 tail = (tail + 1) & RQUEUEMASK;
923 ch->ch_r_tail = tail;
924 ch->ch_err_overrun++;
925 qleft++;
926 }
927
928 ch->ch_equeue[head] = linestatus & (UART_LSR_BI | UART_LSR_PE
929 | UART_LSR_FE);
930 ch->ch_rqueue[head] = readb(&ch->ch_cls_uart->txrx);
931 dgnc_sniff_nowait_nolock(ch, "UART READ",
932 ch->ch_rqueue + head, 1);
933
934 qleft--;
935
936 if (ch->ch_equeue[head] & UART_LSR_PE)
937 ch->ch_err_parity++;
938 if (ch->ch_equeue[head] & UART_LSR_BI)
939 ch->ch_err_break++;
940 if (ch->ch_equeue[head] & UART_LSR_FE)
941 ch->ch_err_frame++;
942
943 /* Add to, and flip head if needed */
944 head = (head + 1) & RQUEUEMASK;
945 ch->ch_rxcount++;
946 }
947
948 /*
949 * Write new final heads to channel structure.
950 */
951 ch->ch_r_head = head & RQUEUEMASK;
952 ch->ch_e_head = head & EQUEUEMASK;
953
954 spin_unlock_irqrestore(&ch->ch_lock, flags);
955 }
956
957
958 /*
959 * This function basically goes to sleep for secs, or until
960 * it gets signalled that the port has fully drained.
961 */
cls_drain(struct tty_struct * tty,uint seconds)962 static int cls_drain(struct tty_struct *tty, uint seconds)
963 {
964 unsigned long flags;
965 struct channel_t *ch;
966 struct un_t *un;
967 int rc = 0;
968
969 if (!tty || tty->magic != TTY_MAGIC)
970 return -ENXIO;
971
972 un = (struct un_t *) tty->driver_data;
973 if (!un || un->magic != DGNC_UNIT_MAGIC)
974 return -ENXIO;
975
976 ch = un->un_ch;
977 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
978 return -ENXIO;
979
980 spin_lock_irqsave(&ch->ch_lock, flags);
981 un->un_flags |= UN_EMPTY;
982 spin_unlock_irqrestore(&ch->ch_lock, flags);
983
984 /*
985 * NOTE: Do something with time passed in.
986 */
987 rc = wait_event_interruptible(un->un_flags_wait,
988 ((un->un_flags & UN_EMPTY) == 0));
989
990 /* If ret is non-zero, user ctrl-c'ed us */
991
992 return rc;
993 }
994
995
996 /* Channel lock MUST be held before calling this function! */
cls_flush_uart_write(struct channel_t * ch)997 static void cls_flush_uart_write(struct channel_t *ch)
998 {
999 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1000 return;
1001
1002 writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT),
1003 &ch->ch_cls_uart->isr_fcr);
1004 udelay(10);
1005
1006 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1007 }
1008
1009
1010 /* Channel lock MUST be held before calling this function! */
cls_flush_uart_read(struct channel_t * ch)1011 static void cls_flush_uart_read(struct channel_t *ch)
1012 {
1013 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1014 return;
1015
1016 /*
1017 * For complete POSIX compatibility, we should be purging the
1018 * read FIFO in the UART here.
1019 *
1020 * However, clearing the read FIFO (UART_FCR_CLEAR_RCVR) also
1021 * incorrectly flushes write data as well as just basically trashing the
1022 * FIFO.
1023 *
1024 * Presumably, this is a bug in this UART.
1025 */
1026
1027 udelay(10);
1028 }
1029
1030
cls_copy_data_from_queue_to_uart(struct channel_t * ch)1031 static void cls_copy_data_from_queue_to_uart(struct channel_t *ch)
1032 {
1033 ushort head;
1034 ushort tail;
1035 int n;
1036 int qlen;
1037 uint len_written = 0;
1038 unsigned long flags;
1039
1040 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1041 return;
1042
1043 spin_lock_irqsave(&ch->ch_lock, flags);
1044
1045 /* No data to write to the UART */
1046 if (ch->ch_w_tail == ch->ch_w_head) {
1047 spin_unlock_irqrestore(&ch->ch_lock, flags);
1048 return;
1049 }
1050
1051 /* If port is "stopped", don't send any data to the UART */
1052 if ((ch->ch_flags & CH_FORCED_STOP) ||
1053 (ch->ch_flags & CH_BREAK_SENDING)) {
1054 spin_unlock_irqrestore(&ch->ch_lock, flags);
1055 return;
1056 }
1057
1058 if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM))) {
1059 spin_unlock_irqrestore(&ch->ch_lock, flags);
1060 return;
1061 }
1062
1063 n = 32;
1064
1065 /* cache head and tail of queue */
1066 head = ch->ch_w_head & WQUEUEMASK;
1067 tail = ch->ch_w_tail & WQUEUEMASK;
1068 qlen = (head - tail) & WQUEUEMASK;
1069
1070 /* Find minimum of the FIFO space, versus queue length */
1071 n = min(n, qlen);
1072
1073 while (n > 0) {
1074
1075 /*
1076 * If RTS Toggle mode is on, turn on RTS now if not already set,
1077 * and make sure we get an event when the data transfer has
1078 * completed.
1079 */
1080 if (ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE) {
1081 if (!(ch->ch_mostat & UART_MCR_RTS)) {
1082 ch->ch_mostat |= (UART_MCR_RTS);
1083 cls_assert_modem_signals(ch);
1084 }
1085 ch->ch_tun.un_flags |= (UN_EMPTY);
1086 }
1087
1088 /*
1089 * If DTR Toggle mode is on, turn on DTR now if not already set,
1090 * and make sure we get an event when the data transfer has
1091 * completed.
1092 */
1093 if (ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE) {
1094 if (!(ch->ch_mostat & UART_MCR_DTR)) {
1095 ch->ch_mostat |= (UART_MCR_DTR);
1096 cls_assert_modem_signals(ch);
1097 }
1098 ch->ch_tun.un_flags |= (UN_EMPTY);
1099 }
1100 writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_cls_uart->txrx);
1101 dgnc_sniff_nowait_nolock(ch, "UART WRITE",
1102 ch->ch_wqueue + ch->ch_w_tail, 1);
1103 ch->ch_w_tail++;
1104 ch->ch_w_tail &= WQUEUEMASK;
1105 ch->ch_txcount++;
1106 len_written++;
1107 n--;
1108 }
1109
1110 if (len_written > 0)
1111 ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1112
1113 spin_unlock_irqrestore(&ch->ch_lock, flags);
1114 }
1115
1116
cls_parse_modem(struct channel_t * ch,unsigned char signals)1117 static void cls_parse_modem(struct channel_t *ch, unsigned char signals)
1118 {
1119 unsigned char msignals = signals;
1120 unsigned long flags;
1121
1122 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1123 return;
1124
1125 /*
1126 * Do altpin switching. Altpin switches DCD and DSR.
1127 * This prolly breaks DSRPACE, so we should be more clever here.
1128 */
1129 spin_lock_irqsave(&ch->ch_lock, flags);
1130 if (ch->ch_digi.digi_flags & DIGI_ALTPIN) {
1131 unsigned char mswap = signals;
1132
1133 if (mswap & UART_MSR_DDCD) {
1134 msignals &= ~UART_MSR_DDCD;
1135 msignals |= UART_MSR_DDSR;
1136 }
1137 if (mswap & UART_MSR_DDSR) {
1138 msignals &= ~UART_MSR_DDSR;
1139 msignals |= UART_MSR_DDCD;
1140 }
1141 if (mswap & UART_MSR_DCD) {
1142 msignals &= ~UART_MSR_DCD;
1143 msignals |= UART_MSR_DSR;
1144 }
1145 if (mswap & UART_MSR_DSR) {
1146 msignals &= ~UART_MSR_DSR;
1147 msignals |= UART_MSR_DCD;
1148 }
1149 }
1150 spin_unlock_irqrestore(&ch->ch_lock, flags);
1151
1152 /*
1153 * Scrub off lower bits. They signify delta's, which I don't
1154 * care about
1155 */
1156 signals &= 0xf0;
1157
1158 spin_lock_irqsave(&ch->ch_lock, flags);
1159 if (msignals & UART_MSR_DCD)
1160 ch->ch_mistat |= UART_MSR_DCD;
1161 else
1162 ch->ch_mistat &= ~UART_MSR_DCD;
1163
1164 if (msignals & UART_MSR_DSR)
1165 ch->ch_mistat |= UART_MSR_DSR;
1166 else
1167 ch->ch_mistat &= ~UART_MSR_DSR;
1168
1169 if (msignals & UART_MSR_RI)
1170 ch->ch_mistat |= UART_MSR_RI;
1171 else
1172 ch->ch_mistat &= ~UART_MSR_RI;
1173
1174 if (msignals & UART_MSR_CTS)
1175 ch->ch_mistat |= UART_MSR_CTS;
1176 else
1177 ch->ch_mistat &= ~UART_MSR_CTS;
1178 spin_unlock_irqrestore(&ch->ch_lock, flags);
1179 }
1180
1181
1182 /* Make the UART raise any of the output signals we want up */
cls_assert_modem_signals(struct channel_t * ch)1183 static void cls_assert_modem_signals(struct channel_t *ch)
1184 {
1185 unsigned char out;
1186
1187 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1188 return;
1189
1190 out = ch->ch_mostat;
1191
1192 if (ch->ch_flags & CH_LOOPBACK)
1193 out |= UART_MCR_LOOP;
1194
1195 writeb(out, &ch->ch_cls_uart->mcr);
1196
1197 /* Give time for the UART to actually drop the signals */
1198 udelay(10);
1199 }
1200
1201
cls_send_start_character(struct channel_t * ch)1202 static void cls_send_start_character(struct channel_t *ch)
1203 {
1204 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1205 return;
1206
1207 if (ch->ch_startc != _POSIX_VDISABLE) {
1208 ch->ch_xon_sends++;
1209 writeb(ch->ch_startc, &ch->ch_cls_uart->txrx);
1210 }
1211 }
1212
1213
cls_send_stop_character(struct channel_t * ch)1214 static void cls_send_stop_character(struct channel_t *ch)
1215 {
1216 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1217 return;
1218
1219 if (ch->ch_stopc != _POSIX_VDISABLE) {
1220 ch->ch_xoff_sends++;
1221 writeb(ch->ch_stopc, &ch->ch_cls_uart->txrx);
1222 }
1223 }
1224
1225
1226 /* Inits UART */
cls_uart_init(struct channel_t * ch)1227 static void cls_uart_init(struct channel_t *ch)
1228 {
1229 unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
1230 unsigned char isr_fcr = 0;
1231
1232 writeb(0, &ch->ch_cls_uart->ier);
1233
1234 /*
1235 * The Enhanced Register Set may only be accessed when
1236 * the Line Control Register is set to 0xBFh.
1237 */
1238 writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
1239
1240 isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
1241
1242 /* Turn on Enhanced/Extended controls */
1243 isr_fcr |= (UART_EXAR654_EFR_ECB);
1244
1245 writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
1246
1247 /* Write old LCR value back out, which turns enhanced access off */
1248 writeb(lcrb, &ch->ch_cls_uart->lcr);
1249
1250 /* Clear out UART and FIFO */
1251 readb(&ch->ch_cls_uart->txrx);
1252
1253 writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT),
1254 &ch->ch_cls_uart->isr_fcr);
1255 udelay(10);
1256
1257 ch->ch_flags |= (CH_FIFO_ENABLED | CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1258
1259 readb(&ch->ch_cls_uart->lsr);
1260 readb(&ch->ch_cls_uart->msr);
1261 }
1262
1263
1264 /*
1265 * Turns off UART.
1266 */
cls_uart_off(struct channel_t * ch)1267 static void cls_uart_off(struct channel_t *ch)
1268 {
1269 writeb(0, &ch->ch_cls_uart->ier);
1270 }
1271
1272
1273 /*
1274 * cls_get_uarts_bytes_left.
1275 * Returns 0 is nothing left in the FIFO, returns 1 otherwise.
1276 *
1277 * The channel lock MUST be held by the calling function.
1278 */
cls_get_uart_bytes_left(struct channel_t * ch)1279 static uint cls_get_uart_bytes_left(struct channel_t *ch)
1280 {
1281 unsigned char left = 0;
1282 unsigned char lsr = 0;
1283
1284 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1285 return 0;
1286
1287 lsr = readb(&ch->ch_cls_uart->lsr);
1288
1289 /* Determine whether the Transmitter is empty or not */
1290 if (!(lsr & UART_LSR_TEMT)) {
1291 if (ch->ch_flags & CH_TX_FIFO_EMPTY)
1292 tasklet_schedule(&ch->ch_bd->helper_tasklet);
1293 left = 1;
1294 } else {
1295 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1296 left = 0;
1297 }
1298
1299 return left;
1300 }
1301
1302
1303 /*
1304 * cls_send_break.
1305 * Starts sending a break thru the UART.
1306 *
1307 * The channel lock MUST be held by the calling function.
1308 */
cls_send_break(struct channel_t * ch,int msecs)1309 static void cls_send_break(struct channel_t *ch, int msecs)
1310 {
1311 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1312 return;
1313
1314 /*
1315 * If we receive a time of 0, this means turn off the break.
1316 */
1317 if (msecs == 0) {
1318 /* Turn break off, and unset some variables */
1319 if (ch->ch_flags & CH_BREAK_SENDING) {
1320 unsigned char temp = readb(&ch->ch_cls_uart->lcr);
1321
1322 writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
1323 ch->ch_flags &= ~(CH_BREAK_SENDING);
1324 ch->ch_stop_sending_break = 0;
1325 }
1326 return;
1327 }
1328
1329 /*
1330 * Set the time we should stop sending the break.
1331 * If we are already sending a break, toss away the existing
1332 * time to stop, and use this new value instead.
1333 */
1334 ch->ch_stop_sending_break = jiffies + dgnc_jiffies_from_ms(msecs);
1335
1336 /* Tell the UART to start sending the break */
1337 if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1338 unsigned char temp = readb(&ch->ch_cls_uart->lcr);
1339
1340 writeb((temp | UART_LCR_SBC), &ch->ch_cls_uart->lcr);
1341 ch->ch_flags |= (CH_BREAK_SENDING);
1342 }
1343 }
1344
1345
1346 /*
1347 * cls_send_immediate_char.
1348 * Sends a specific character as soon as possible to the UART,
1349 * jumping over any bytes that might be in the write queue.
1350 *
1351 * The channel lock MUST be held by the calling function.
1352 */
cls_send_immediate_char(struct channel_t * ch,unsigned char c)1353 static void cls_send_immediate_char(struct channel_t *ch, unsigned char c)
1354 {
1355 if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1356 return;
1357
1358 writeb(c, &ch->ch_cls_uart->txrx);
1359 }
1360
cls_vpd(struct dgnc_board * brd)1361 static void cls_vpd(struct dgnc_board *brd)
1362 {
1363 ulong vpdbase; /* Start of io base of the card */
1364 u8 __iomem *re_map_vpdbase;/* Remapped memory of the card */
1365 int i = 0;
1366
1367
1368 vpdbase = pci_resource_start(brd->pdev, 3);
1369
1370 /* No VPD */
1371 if (!vpdbase)
1372 return;
1373
1374 re_map_vpdbase = ioremap(vpdbase, 0x400);
1375
1376 if (!re_map_vpdbase)
1377 return;
1378
1379 /* Store the VPD into our buffer */
1380 for (i = 0; i < 0x40; i++) {
1381 brd->vpd[i] = readb(re_map_vpdbase + i);
1382 pr_info("%x ", brd->vpd[i]);
1383 }
1384 pr_info("\n");
1385
1386 if (re_map_vpdbase)
1387 iounmap(re_map_vpdbase);
1388 }
1389
1390