drivers/staging/dgnc/dgnc_cls.c

   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 #include "dgnc_trace.h"
  45
  46 static inline void cls_parse_isr(struct dgnc_board *brd, uint port);
  47 static inline void cls_clear_break(struct channel_t *ch, int force);
  48 static inline void cls_set_cts_flow_control(struct channel_t *ch);
  49 static inline void cls_set_rts_flow_control(struct channel_t *ch);
  50 static inline void cls_set_ixon_flow_control(struct channel_t *ch);
  51 static inline void cls_set_ixoff_flow_control(struct channel_t *ch);
  52 static inline void cls_set_no_output_flow_control(struct channel_t *ch);
  53 static inline void cls_set_no_input_flow_control(struct channel_t *ch);
  54 static void cls_parse_modem(struct channel_t *ch, uchar signals);
  55 static void cls_tasklet(unsigned long data);
  56 static void cls_vpd(struct dgnc_board *brd);
  57 static void cls_uart_init(struct channel_t *ch);
  58 static void cls_uart_off(struct channel_t *ch);
  59 static int cls_drain(struct tty_struct *tty, uint seconds);
  60 static void cls_param(struct tty_struct *tty);
  61 static void cls_assert_modem_signals(struct channel_t *ch);
  62 static void cls_flush_uart_write(struct channel_t *ch);
  63 static void cls_flush_uart_read(struct channel_t *ch);
  64 static void cls_disable_receiver(struct channel_t *ch);
  65 static void cls_enable_receiver(struct channel_t *ch);
  66 static void cls_send_break(struct channel_t *ch, int msecs);
  67 static void cls_send_start_character(struct channel_t *ch);
  68 static void cls_send_stop_character(struct channel_t *ch);
  69 static void cls_copy_data_from_uart_to_queue(struct channel_t *ch);
  70 static void cls_copy_data_from_queue_to_uart(struct channel_t *ch);
  71 static uint cls_get_uart_bytes_left(struct channel_t *ch);
  72 static void cls_send_immediate_char(struct channel_t *ch, unsigned char);
  73 static irqreturn_t cls_intr(int irq, void *voidbrd);
  74
  75 struct board_ops dgnc_cls_ops = {
  76         .tasklet =                      cls_tasklet,
  77         .intr =                         cls_intr,
  78         .uart_init =                    cls_uart_init,
  79         .uart_off =                     cls_uart_off,
  80         .drain =                        cls_drain,
  81         .param =                        cls_param,
  82         .vpd =                          cls_vpd,
  83         .assert_modem_signals =         cls_assert_modem_signals,
  84         .flush_uart_write =             cls_flush_uart_write,
  85         .flush_uart_read =              cls_flush_uart_read,
  86         .disable_receiver =             cls_disable_receiver,
  87         .enable_receiver =              cls_enable_receiver,
  88         .send_break =                   cls_send_break,
  89         .send_start_character =         cls_send_start_character,
  90         .send_stop_character =          cls_send_stop_character,
  91         .copy_data_from_queue_to_uart = cls_copy_data_from_queue_to_uart,
  92         .get_uart_bytes_left =          cls_get_uart_bytes_left,
  93         .send_immediate_char =          cls_send_immediate_char
  94 };
  95
  96
  97 static inline void cls_set_cts_flow_control(struct channel_t *ch)
  98 {
  99         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
 100         uchar ier = readb(&ch->ch_cls_uart->ier);
 101         uchar isr_fcr = 0;
 102
 103         DPR_PARAM(("Setting CTSFLOW\n"));
 104
 105         /*
 106          * The Enhanced Register Set may only be accessed when
 107          * the Line Control Register is set to 0xBFh.
 108          */
 109         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
 110
 111         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
 112
 113         /* Turn on CTS flow control, turn off IXON flow control */
 114         isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_CTSDSR);
 115         isr_fcr &= ~(UART_EXAR654_EFR_IXON);
 116
 117         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
 118
 119         /* Write old LCR value back out, which turns enhanced access off */
 120         writeb(lcrb, &ch->ch_cls_uart->lcr);
 121
 122         /*
 123          * Enable interrupts for CTS flow, turn off interrupts for
 124          * received XOFF chars
 125          */
 126         ier |= (UART_EXAR654_IER_CTSDSR);
 127         ier &= ~(UART_EXAR654_IER_XOFF);
 128         writeb(ier, &ch->ch_cls_uart->ier);
 129
 130         /* Set the usual FIFO values */
 131         writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
 132
 133         writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_56 |
 134                 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
 135                 &ch->ch_cls_uart->isr_fcr);
 136
 137         ch->ch_t_tlevel = 16;
 138
 139 }
 140
 141
 142 static inline void cls_set_ixon_flow_control(struct channel_t *ch)
 143 {
 144         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
 145         uchar ier = readb(&ch->ch_cls_uart->ier);
 146         uchar isr_fcr = 0;
 147
 148         DPR_PARAM(("Setting IXON FLOW\n"));
 149
 150         /*
 151          * The Enhanced Register Set may only be accessed when
 152          * the Line Control Register is set to 0xBFh.
 153          */
 154         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
 155
 156         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
 157
 158         /* Turn on IXON flow control, turn off CTS flow control */
 159         isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_IXON);
 160         isr_fcr &= ~(UART_EXAR654_EFR_CTSDSR);
 161
 162         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
 163
 164         /* Now set our current start/stop chars while in enhanced mode */
 165         writeb(ch->ch_startc, &ch->ch_cls_uart->mcr);
 166         writeb(0, &ch->ch_cls_uart->lsr);
 167         writeb(ch->ch_stopc, &ch->ch_cls_uart->msr);
 168         writeb(0, &ch->ch_cls_uart->spr);
 169
 170         /* Write old LCR value back out, which turns enhanced access off */
 171         writeb(lcrb, &ch->ch_cls_uart->lcr);
 172
 173         /*
 174          * Disable interrupts for CTS flow, turn on interrupts for
 175          * received XOFF chars
 176          */
 177         ier &= ~(UART_EXAR654_IER_CTSDSR);
 178         ier |= (UART_EXAR654_IER_XOFF);
 179         writeb(ier, &ch->ch_cls_uart->ier);
 180
 181         /* Set the usual FIFO values */
 182         writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
 183
 184         writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
 185                 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
 186                 &ch->ch_cls_uart->isr_fcr);
 187
 188 }
 189
 190
 191 static inline void cls_set_no_output_flow_control(struct channel_t *ch)
 192 {
 193         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
 194         uchar ier = readb(&ch->ch_cls_uart->ier);
 195         uchar isr_fcr = 0;
 196
 197         DPR_PARAM(("Unsetting Output FLOW\n"));
 198
 199         /*
 200          * The Enhanced Register Set may only be accessed when
 201          * the Line Control Register is set to 0xBFh.
 202          */
 203         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
 204
 205         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
 206
 207         /* Turn off IXON flow control, turn off CTS flow control */
 208         isr_fcr |= (UART_EXAR654_EFR_ECB);
 209         isr_fcr &= ~(UART_EXAR654_EFR_CTSDSR | UART_EXAR654_EFR_IXON);
 210
 211         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
 212
 213         /* Write old LCR value back out, which turns enhanced access off */
 214         writeb(lcrb, &ch->ch_cls_uart->lcr);
 215
 216         /*
 217          * Disable interrupts for CTS flow, turn off interrupts for
 218          * received XOFF chars
 219          */
 220         ier &= ~(UART_EXAR654_IER_CTSDSR);
 221         ier &= ~(UART_EXAR654_IER_XOFF);
 222         writeb(ier, &ch->ch_cls_uart->ier);
 223
 224         /* Set the usual FIFO values */
 225         writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
 226
 227         writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
 228                 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
 229                 &ch->ch_cls_uart->isr_fcr);
 230
 231         ch->ch_r_watermark = 0;
 232         ch->ch_t_tlevel = 16;
 233         ch->ch_r_tlevel = 16;
 234
 235 }
 236
 237
 238 static inline void cls_set_rts_flow_control(struct channel_t *ch)
 239 {
 240         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
 241         uchar ier = readb(&ch->ch_cls_uart->ier);
 242         uchar isr_fcr = 0;
 243
 244         DPR_PARAM(("Setting RTSFLOW\n"));
 245
 246         /*
 247          * The Enhanced Register Set may only be accessed when
 248          * the Line Control Register is set to 0xBFh.
 249          */
 250         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
 251
 252         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
 253
 254         /* Turn on RTS flow control, turn off IXOFF flow control */
 255         isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_RTSDTR);
 256         isr_fcr &= ~(UART_EXAR654_EFR_IXOFF);
 257
 258         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
 259
 260         /* Write old LCR value back out, which turns enhanced access off */
 261         writeb(lcrb, &ch->ch_cls_uart->lcr);
 262
 263         /* Enable interrupts for RTS flow */
 264         ier |= (UART_EXAR654_IER_RTSDTR);
 265         writeb(ier, &ch->ch_cls_uart->ier);
 266
 267         /* Set the usual FIFO values */
 268         writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
 269
 270         writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_56 |
 271                 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
 272                 &ch->ch_cls_uart->isr_fcr);
 273
 274
 275         ch->ch_r_watermark = 4;
 276         ch->ch_r_tlevel = 8;
 277
 278 }
 279
 280
 281 static inline void cls_set_ixoff_flow_control(struct channel_t *ch)
 282 {
 283         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
 284         uchar ier = readb(&ch->ch_cls_uart->ier);
 285         uchar isr_fcr = 0;
 286
 287         DPR_PARAM(("Setting IXOFF FLOW\n"));
 288
 289         /*
 290          * The Enhanced Register Set may only be accessed when
 291          * the Line Control Register is set to 0xBFh.
 292          */
 293         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
 294
 295         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
 296
 297         /* Turn on IXOFF flow control, turn off RTS flow control */
 298         isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_IXOFF);
 299         isr_fcr &= ~(UART_EXAR654_EFR_RTSDTR);
 300
 301         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
 302
 303         /* Now set our current start/stop chars while in enhanced mode */
 304         writeb(ch->ch_startc, &ch->ch_cls_uart->mcr);
 305         writeb(0, &ch->ch_cls_uart->lsr);
 306         writeb(ch->ch_stopc, &ch->ch_cls_uart->msr);
 307         writeb(0, &ch->ch_cls_uart->spr);
 308
 309         /* Write old LCR value back out, which turns enhanced access off */
 310         writeb(lcrb, &ch->ch_cls_uart->lcr);
 311
 312         /* Disable interrupts for RTS flow */
 313         ier &= ~(UART_EXAR654_IER_RTSDTR);
 314         writeb(ier, &ch->ch_cls_uart->ier);
 315
 316         /* Set the usual FIFO values */
 317         writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
 318
 319         writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
 320                 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
 321                 &ch->ch_cls_uart->isr_fcr);
 322
 323 }
 324
 325
 326 static inline void cls_set_no_input_flow_control(struct channel_t *ch)
 327 {
 328         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
 329         uchar ier = readb(&ch->ch_cls_uart->ier);
 330         uchar isr_fcr = 0;
 331
 332         DPR_PARAM(("Unsetting Input FLOW\n"));
 333
 334         /*
 335          * The Enhanced Register Set may only be accessed when
 336          * the Line Control Register is set to 0xBFh.
 337          */
 338         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
 339
 340         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
 341
 342         /* Turn off IXOFF flow control, turn off RTS flow control */
 343         isr_fcr |= (UART_EXAR654_EFR_ECB);
 344         isr_fcr &= ~(UART_EXAR654_EFR_RTSDTR | UART_EXAR654_EFR_IXOFF);
 345
 346         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
 347
 348         /* Write old LCR value back out, which turns enhanced access off */
 349         writeb(lcrb, &ch->ch_cls_uart->lcr);
 350
 351         /* Disable interrupts for RTS flow */
 352         ier &= ~(UART_EXAR654_IER_RTSDTR);
 353         writeb(ier, &ch->ch_cls_uart->ier);
 354
 355         /* Set the usual FIFO values */
 356         writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
 357
 358         writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
 359                 UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
 360                 &ch->ch_cls_uart->isr_fcr);
 361
 362         ch->ch_t_tlevel = 16;
 363         ch->ch_r_tlevel = 16;
 364
 365 }
 366
 367
 368 /*
 369  * cls_clear_break.
 370  * Determines whether its time to shut off break condition.
 371  *
 372  * No locks are assumed to be held when calling this function.
 373  * channel lock is held and released in this function.
 374  */
 375 static inline void cls_clear_break(struct channel_t *ch, int force)
 376 {
 377         ulong lock_flags;
 378
 379         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
 380                 return;
 381
 382         DGNC_LOCK(ch->ch_lock, lock_flags);
 383
 384         /* Bail if we aren't currently sending a break. */
 385         if (!ch->ch_stop_sending_break) {
 386                 DGNC_UNLOCK(ch->ch_lock, lock_flags);
 387                 return;
 388         }
 389
 390         /* Turn break off, and unset some variables */
 391         if (ch->ch_flags & CH_BREAK_SENDING) {
 392                 if (time_after(jiffies, ch->ch_stop_sending_break) || force) {
 393                         uchar temp = readb(&ch->ch_cls_uart->lcr);
 394                         writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
 395                         ch->ch_flags &= ~(CH_BREAK_SENDING);
 396                         ch->ch_stop_sending_break = 0;
 397                         DPR_IOCTL(("Finishing UART_LCR_SBC! finished: %lx\n",
 398                                                                 jiffies));
 399                 }
 400         }
 401         DGNC_UNLOCK(ch->ch_lock, lock_flags);
 402 }
 403
 404
 405 /* Parse the ISR register for the specific port */
 406 static inline void cls_parse_isr(struct dgnc_board *brd, uint port)
 407 {
 408         struct channel_t *ch;
 409         uchar isr = 0;
 410         ulong lock_flags;
 411
 412         /*
 413          * No need to verify board pointer, it was already
 414          * verified in the interrupt routine.
 415          */
 416
 417         if (port > brd->nasync)
 418                 return;
 419
 420         ch = brd->channels[port];
 421         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
 422                 return;
 423
 424         /* Here we try to figure out what caused the interrupt to happen */
 425         while (1) {
 426
 427                 isr = readb(&ch->ch_cls_uart->isr_fcr);
 428
 429                 /* Bail if no pending interrupt on port */
 430                 if (isr & UART_IIR_NO_INT)
 431                         break;
 432
 433                 DPR_INTR(("%s:%d port: %x isr: %x\n", __FILE__, __LINE__,
 434                                                                  port, isr));
 435
 436                 /* Receive Interrupt pending */
 437                 if (isr & (UART_IIR_RDI | UART_IIR_RDI_TIMEOUT)) {
 438                         /* Read data from uart -> queue */
 439                         brd->intr_rx++;
 440                         ch->ch_intr_rx++;
 441                         cls_copy_data_from_uart_to_queue(ch);
 442                         dgnc_check_queue_flow_control(ch);
 443                 }
 444
 445                 /* Transmit Hold register empty pending */
 446                 if (isr & UART_IIR_THRI) {
 447                         /* Transfer data (if any) from Write Queue -> UART. */
 448                         DGNC_LOCK(ch->ch_lock, lock_flags);
 449                         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 450                         brd->intr_tx++;
 451                         ch->ch_intr_tx++;
 452                         DGNC_UNLOCK(ch->ch_lock, lock_flags);
 453                         cls_copy_data_from_queue_to_uart(ch);
 454                 }
 455
 456                 /* Received Xoff signal/Special character */
 457                 if (isr & UART_IIR_XOFF)
 458                         /* Empty */
 459
 460                 /* CTS/RTS change of state */
 461                 if (isr & UART_IIR_CTSRTS) {
 462                         brd->intr_modem++;
 463                         ch->ch_intr_modem++;
 464                         /*
 465                          * Don't need to do anything, the cls_parse_modem
 466                          * below will grab the updated modem signals.
 467                          */
 468                 }
 469
 470                 /* Parse any modem signal changes */
 471                 DPR_INTR(("MOD_STAT: sending to parse_modem_sigs\n"));
 472                 cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));
 473         }
 474 }
 475
 476
 477 /*
 478  * cls_param()
 479  * Send any/all changes to the line to the UART.
 480  */
 481 static void cls_param(struct tty_struct *tty)
 482 {
 483         uchar lcr = 0;
 484         uchar uart_lcr = 0;
 485         uchar ier = 0;
 486         uchar uart_ier = 0;
 487         uint baud = 9600;
 488         int quot = 0;
 489         struct dgnc_board *bd;
 490         struct channel_t *ch;
 491         struct un_t   *un;
 492
 493         if (!tty || tty->magic != TTY_MAGIC)
 494                 return;
 495
 496         un = (struct un_t *) tty->driver_data;
 497         if (!un || un->magic != DGNC_UNIT_MAGIC)
 498                 return;
 499
 500         ch = un->un_ch;
 501         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
 502                 return;
 503
 504         bd = ch->ch_bd;
 505         if (!bd || bd->magic != DGNC_BOARD_MAGIC)
 506                 return;
 507
 508         DPR_PARAM(("param start: tdev: %x cflags: %x oflags: %x iflags: %x\n",
 509                 ch->ch_tun.un_dev, ch->ch_c_cflag, ch->ch_c_oflag,
 510                                                          ch->ch_c_iflag));
 511
 512         /*
 513          * If baud rate is zero, flush queues, and set mval to drop DTR.
 514          */
 515         if ((ch->ch_c_cflag & (CBAUD)) == 0) {
 516                 ch->ch_r_head = ch->ch_r_tail = 0;
 517                 ch->ch_e_head = ch->ch_e_tail = 0;
 518                 ch->ch_w_head = ch->ch_w_tail = 0;
 519
 520                 cls_flush_uart_write(ch);
 521                 cls_flush_uart_read(ch);
 522
 523                 /* The baudrate is B0 so all modem lines are to be dropped. */
 524                 ch->ch_flags |= (CH_BAUD0);
 525                 ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
 526                 cls_assert_modem_signals(ch);
 527                 ch->ch_old_baud = 0;
 528                 return;
 529         } else if (ch->ch_custom_speed) {
 530
 531                 baud = ch->ch_custom_speed;
 532                 /* Handle transition from B0 */
 533                 if (ch->ch_flags & CH_BAUD0) {
 534                         ch->ch_flags &= ~(CH_BAUD0);
 535
 536                         /*
 537                          * Bring back up RTS and DTR...
 538                          * Also handle RTS or DTR toggle if set.
 539                          */
 540                         if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))
 541                                 ch->ch_mostat |= (UART_MCR_RTS);
 542                         if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))
 543                                 ch->ch_mostat |= (UART_MCR_DTR);
 544                 }
 545
 546         } else {
 547                 int iindex = 0;
 548                 int jindex = 0;
 549
 550                 ulong bauds[4][16] = {
 551                         { /* slowbaud */
 552                                 0,      50,     75,     110,
 553                                 134,    150,    200,    300,
 554                                 600,    1200,   1800,   2400,
 555                                 4800,   9600,   19200,  38400 },
 556                         { /* slowbaud & CBAUDEX */
 557                                 0,      57600,  115200, 230400,
 558                                 460800, 150,    200,    921600,
 559                                 600,    1200,   1800,   2400,
 560                                 4800,   9600,   19200,  38400 },
 561                         { /* fastbaud */
 562                                 0,      57600,   76800, 115200,
 563                                 131657, 153600, 230400, 460800,
 564                                 921600, 1200,   1800,   2400,
 565                                 4800,   9600,   19200,  38400 },
 566                         { /* fastbaud & CBAUDEX */
 567                                 0,      57600,  115200, 230400,
 568                                 460800, 150,    200,    921600,
 569                                 600,    1200,   1800,   2400,
 570                                 4800,   9600,   19200,  38400 }
 571                 };
 572
 573                 /*
 574                  * Only use the TXPrint baud rate if the terminal
 575                  * unit is NOT open
 576                  */
 577                 if (!(ch->ch_tun.un_flags & UN_ISOPEN) &&
 578                                          (un->un_type == DGNC_PRINT))
 579                         baud = C_BAUD(ch->ch_pun.un_tty) & 0xff;
 580                 else
 581                         baud = C_BAUD(ch->ch_tun.un_tty) & 0xff;
 582
 583                 if (ch->ch_c_cflag & CBAUDEX)
 584                         iindex = 1;
 585
 586                 if (ch->ch_digi.digi_flags & DIGI_FAST)
 587                         iindex += 2;
 588
 589                 jindex = baud;
 590
 591                 if ((iindex >= 0) && (iindex < 4) && (jindex >= 0) &&
 592                                                                 (jindex < 16)) {
 593                         baud = bauds[iindex][jindex];
 594                 } else {
 595                         DPR_IOCTL(("baud indices were out of range (%d)(%d)",
 596                                 iindex, jindex));
 597                         baud = 0;
 598                 }
 599
 600                 if (baud == 0)
 601                         baud = 9600;
 602
 603                 /* Handle transition from B0 */
 604                 if (ch->ch_flags & CH_BAUD0) {
 605                         ch->ch_flags &= ~(CH_BAUD0);
 606
 607                         /*
 608                          * Bring back up RTS and DTR...
 609                          * Also handle RTS or DTR toggle if set.
 610                          */
 611                         if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))
 612                                 ch->ch_mostat |= (UART_MCR_RTS);
 613                         if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))
 614                                 ch->ch_mostat |= (UART_MCR_DTR);
 615                 }
 616         }
 617
 618         if (ch->ch_c_cflag & PARENB)
 619                 lcr |= UART_LCR_PARITY;
 620
 621         if (!(ch->ch_c_cflag & PARODD))
 622                 lcr |= UART_LCR_EPAR;
 623
 624         /*
 625          * Not all platforms support mark/space parity,
 626          * so this will hide behind an ifdef.
 627          */
 628 #ifdef CMSPAR
 629         if (ch->ch_c_cflag & CMSPAR)
 630                 lcr |= UART_LCR_SPAR;
 631 #endif
 632
 633         if (ch->ch_c_cflag & CSTOPB)
 634                 lcr |= UART_LCR_STOP;
 635
 636         switch (ch->ch_c_cflag & CSIZE) {
 637         case CS5:
 638                 lcr |= UART_LCR_WLEN5;
 639                 break;
 640         case CS6:
 641                 lcr |= UART_LCR_WLEN6;
 642                 break;
 643         case CS7:
 644                 lcr |= UART_LCR_WLEN7;
 645                 break;
 646         case CS8:
 647         default:
 648                 lcr |= UART_LCR_WLEN8;
 649                 break;
 650         }
 651
 652         ier = uart_ier = readb(&ch->ch_cls_uart->ier);
 653         uart_lcr = readb(&ch->ch_cls_uart->lcr);
 654
 655         if (baud == 0)
 656                 baud = 9600;
 657
 658         quot = ch->ch_bd->bd_dividend / baud;
 659
 660         if (quot != 0 && ch->ch_old_baud != baud) {
 661                 ch->ch_old_baud = baud;
 662                 writeb(UART_LCR_DLAB, &ch->ch_cls_uart->lcr);
 663                 writeb((quot & 0xff), &ch->ch_cls_uart->txrx);
 664                 writeb((quot >> 8), &ch->ch_cls_uart->ier);
 665                 writeb(lcr, &ch->ch_cls_uart->lcr);
 666         }
 667
 668         if (uart_lcr != lcr)
 669                 writeb(lcr, &ch->ch_cls_uart->lcr);
 670
 671         if (ch->ch_c_cflag & CREAD)
 672                 ier |= (UART_IER_RDI | UART_IER_RLSI);
 673         else
 674                 ier &= ~(UART_IER_RDI | UART_IER_RLSI);
 675
 676         /*
 677          * Have the UART interrupt on modem signal changes ONLY when
 678          * we are in hardware flow control mode, or CLOCAL/FORCEDCD is not set.
 679          */
 680         if ((ch->ch_digi.digi_flags & CTSPACE) ||
 681                 (ch->ch_digi.digi_flags & RTSPACE) ||
 682                 (ch->ch_c_cflag & CRTSCTS) ||
 683                 !(ch->ch_digi.digi_flags & DIGI_FORCEDCD) ||
 684                 !(ch->ch_c_cflag & CLOCAL))
 685                         ier |= UART_IER_MSI;
 686         else
 687                         ier &= ~UART_IER_MSI;
 688
 689         ier |= UART_IER_THRI;
 690
 691         if (ier != uart_ier)
 692                 writeb(ier, &ch->ch_cls_uart->ier);
 693
 694         if (ch->ch_digi.digi_flags & CTSPACE || ch->ch_c_cflag & CRTSCTS) {
 695                 cls_set_cts_flow_control(ch);
 696         } else if (ch->ch_c_iflag & IXON) {
 697                 /*
 698                  * If start/stop is set to disable, then we should
 699                  * disable flow control
 700                  */
 701                 if ((ch->ch_startc == _POSIX_VDISABLE) ||
 702                                          (ch->ch_stopc == _POSIX_VDISABLE))
 703                         cls_set_no_output_flow_control(ch);
 704                 else
 705                         cls_set_ixon_flow_control(ch);
 706         } else {
 707                 cls_set_no_output_flow_control(ch);
 708         }
 709
 710         if (ch->ch_digi.digi_flags & RTSPACE || ch->ch_c_cflag & CRTSCTS) {
 711                 cls_set_rts_flow_control(ch);
 712         } else if (ch->ch_c_iflag & IXOFF) {
 713                 /*
 714                  * If start/stop is set to disable, then we should disable
 715                  * flow control
 716                  */
 717                 if ((ch->ch_startc == _POSIX_VDISABLE) ||
 718                                 (ch->ch_stopc == _POSIX_VDISABLE))
 719                         cls_set_no_input_flow_control(ch);
 720                 else
 721                         cls_set_ixoff_flow_control(ch);
 722         } else {
 723                 cls_set_no_input_flow_control(ch);
 724         }
 725
 726         cls_assert_modem_signals(ch);
 727
 728         /* Get current status of the modem signals now */
 729         cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));
 730 }
 731
 732
 733 /*
 734  * Our board poller function.
 735  */
 736 static void cls_tasklet(unsigned long data)
 737 {
 738         struct dgnc_board *bd = (struct dgnc_board *) data;
 739         struct channel_t *ch;
 740         ulong  lock_flags;
 741         int i;
 742         int state = 0;
 743         int ports = 0;
 744
 745         if (!bd || bd->magic != DGNC_BOARD_MAGIC) {
 746                 APR(("poll_tasklet() - NULL or bad bd.\n"));
 747                 return;
 748         }
 749
 750         /* Cache a couple board values */
 751         DGNC_LOCK(bd->bd_lock, lock_flags);
 752         state = bd->state;
 753         ports = bd->nasync;
 754         DGNC_UNLOCK(bd->bd_lock, lock_flags);
 755
 756         /*
 757          * Do NOT allow the interrupt routine to read the intr registers
 758          * Until we release this lock.
 759          */
 760         DGNC_LOCK(bd->bd_intr_lock, lock_flags);
 761
 762         /*
 763          * If board is ready, parse deeper to see if there is anything to do.
 764          */
 765         if ((state == BOARD_READY) && (ports > 0)) {
 766
 767                 /* Loop on each port */
 768                 for (i = 0; i < ports; i++) {
 769                         ch = bd->channels[i];
 770                         if (!ch)
 771                                 continue;
 772
 773                         /*
 774                          * NOTE: Remember you CANNOT hold any channel
 775                          * locks when calling input.
 776                          * During input processing, its possible we
 777                          * will call ld, which might do callbacks back
 778                          * into us.
 779                          */
 780                         dgnc_input(ch);
 781
 782                         /*
 783                          * Channel lock is grabbed and then released
 784                          * inside this routine.
 785                          */
 786                         cls_copy_data_from_queue_to_uart(ch);
 787                         dgnc_wakeup_writes(ch);
 788
 789                         /*
 790                          * Check carrier function.
 791                          */
 792                         dgnc_carrier(ch);
 793
 794                         /*
 795                          * The timing check of turning off the break is done
 796                          * inside clear_break()
 797                          */
 798                         if (ch->ch_stop_sending_break)
 799                                 cls_clear_break(ch, 0);
 800                 }
 801         }
 802
 803         DGNC_UNLOCK(bd->bd_intr_lock, lock_flags);
 804
 805 }
 806
 807
 808 /*
 809  * cls_intr()
 810  *
 811  * Classic specific interrupt handler.
 812  */
 813 static irqreturn_t cls_intr(int irq, void *voidbrd)
 814 {
 815         struct dgnc_board *brd = (struct dgnc_board *) voidbrd;
 816         uint i = 0;
 817         uchar poll_reg;
 818         unsigned long lock_flags;
 819
 820         if (!brd) {
 821                 APR(("Received interrupt (%d) with null board associated\n",
 822                                                                          irq));
 823                 return IRQ_NONE;
 824         }
 825
 826         /*
 827          * Check to make sure its for us.
 828          */
 829         if (brd->magic != DGNC_BOARD_MAGIC) {
 830                 APR(("Received interrupt (%d) with a board pointer that wasn't ours!\n",
 831                           irq));
 832                 return IRQ_NONE;
 833         }
 834
 835         DGNC_LOCK(brd->bd_intr_lock, lock_flags);
 836
 837         brd->intr_count++;
 838
 839         /*
 840          * Check the board's global interrupt offset to see if we
 841          * we actually do have an interrupt pending for us.
 842          */
 843         poll_reg = readb(brd->re_map_membase + UART_CLASSIC_POLL_ADDR_OFFSET);
 844
 845         /* If 0, no interrupts pending */
 846         if (!poll_reg) {
 847                 DPR_INTR((
 848                          "Kernel interrupted to me, but no pending interrupts...\n"));
 849                 DGNC_UNLOCK(brd->bd_intr_lock, lock_flags);
 850                 return IRQ_NONE;
 851         }
 852
 853         DPR_INTR(("%s:%d poll_reg: %x\n", __FILE__, __LINE__, poll_reg));
 854
 855         /* Parse each port to find out what caused the interrupt */
 856         for (i = 0; i < brd->nasync; i++)
 857                 cls_parse_isr(brd, i);
 858
 859         /*
 860          * Schedule tasklet to more in-depth servicing at a better time.
 861          */
 862         tasklet_schedule(&brd->helper_tasklet);
 863
 864         DGNC_UNLOCK(brd->bd_intr_lock, lock_flags);
 865
 866         DPR_INTR(("dgnc_intr finish.\n"));
 867         return IRQ_HANDLED;
 868 }
 869
 870
 871 static void cls_disable_receiver(struct channel_t *ch)
 872 {
 873         uchar tmp = readb(&ch->ch_cls_uart->ier);
 874         tmp &= ~(UART_IER_RDI);
 875         writeb(tmp, &ch->ch_cls_uart->ier);
 876 }
 877
 878
 879 static void cls_enable_receiver(struct channel_t *ch)
 880 {
 881         uchar tmp = readb(&ch->ch_cls_uart->ier);
 882         tmp |= (UART_IER_RDI);
 883         writeb(tmp, &ch->ch_cls_uart->ier);
 884 }
 885
 886
 887 static void cls_copy_data_from_uart_to_queue(struct channel_t *ch)
 888 {
 889         int qleft = 0;
 890         uchar linestatus = 0;
 891         uchar error_mask = 0;
 892         ushort head;
 893         ushort tail;
 894         ulong lock_flags;
 895
 896         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
 897                 return;
 898
 899         DGNC_LOCK(ch->ch_lock, lock_flags);
 900
 901         /* cache head and tail of queue */
 902         head = ch->ch_r_head;
 903         tail = ch->ch_r_tail;
 904
 905         /* Store how much space we have left in the queue */
 906         qleft = (tail - head - 1);
 907         if (qleft < 0)
 908                 qleft += RQUEUEMASK + 1;
 909
 910         /*
 911          * Create a mask to determine whether we should
 912          * insert the character (if any) into our queue.
 913          */
 914         if (ch->ch_c_iflag & IGNBRK)
 915                 error_mask |= UART_LSR_BI;
 916
 917         while (1) {
 918                 linestatus = readb(&ch->ch_cls_uart->lsr);
 919
 920                 if (!(linestatus & (UART_LSR_DR)))
 921                         break;
 922
 923                 /*
 924                  * Discard character if we are ignoring the error mask.
 925                 */
 926                 if (linestatus & error_mask)  {
 927                         uchar discard;
 928                         linestatus = 0;
 929                         discard = readb(&ch->ch_cls_uart->txrx);
 930                         continue;
 931                 }
 932
 933                 /*
 934                  * If our queue is full, we have no choice but to drop some
 935                  * data. The assumption is that HWFLOW or SWFLOW should have
 936                  * stopped things way way before we got to this point.
 937                  *
 938                  * I decided that I wanted to ditch the oldest data first,
 939                  * I hope thats okay with everyone? Yes? Good.
 940                  */
 941                 while (qleft < 1) {
 942                         DPR_READ(("Queue full, dropping DATA:%x LSR:%x\n",
 943                                 ch->ch_rqueue[tail], ch->ch_equeue[tail]));
 944
 945                         ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK;
 946                         ch->ch_err_overrun++;
 947                         qleft++;
 948                 }
 949
 950                 ch->ch_equeue[head] = linestatus & (UART_LSR_BI | UART_LSR_PE
 951                                                                  | UART_LSR_FE);
 952                 ch->ch_rqueue[head] = readb(&ch->ch_cls_uart->txrx);
 953                 dgnc_sniff_nowait_nolock(ch, "UART READ",
 954                                                  ch->ch_rqueue + head, 1);
 955
 956                 qleft--;
 957
 958                 DPR_READ(("DATA/LSR pair: %x %x\n", ch->ch_rqueue[head],
 959                                                          ch->ch_equeue[head]));
 960
 961                 if (ch->ch_equeue[head] & UART_LSR_PE)
 962                         ch->ch_err_parity++;
 963                 if (ch->ch_equeue[head] & UART_LSR_BI)
 964                         ch->ch_err_break++;
 965                 if (ch->ch_equeue[head] & UART_LSR_FE)
 966                         ch->ch_err_frame++;
 967
 968                 /* Add to, and flip head if needed */
 969                 head = (head + 1) & RQUEUEMASK;
 970                 ch->ch_rxcount++;
 971         }
 972
 973         /*
 974          * Write new final heads to channel structure.
 975          */
 976         ch->ch_r_head = head & RQUEUEMASK;
 977         ch->ch_e_head = head & EQUEUEMASK;
 978
 979         DGNC_UNLOCK(ch->ch_lock, lock_flags);
 980 }
 981
 982
 983 /*
 984  * This function basically goes to sleep for secs, or until
 985  * it gets signalled that the port has fully drained.
 986  */
 987 static int cls_drain(struct tty_struct *tty, uint seconds)
 988 {
 989         ulong lock_flags;
 990         struct channel_t *ch;
 991         struct un_t *un;
 992         int rc = 0;
 993
 994         if (!tty || tty->magic != TTY_MAGIC)
 995                 return -ENXIO;
 996
 997         un = (struct un_t *) tty->driver_data;
 998         if (!un || un->magic != DGNC_UNIT_MAGIC)
 999                 return -ENXIO;
1000
1001         ch = un->un_ch;
1002         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1003                 return -ENXIO;
1004
1005         DGNC_LOCK(ch->ch_lock, lock_flags);
1006         un->un_flags |= UN_EMPTY;
1007         DGNC_UNLOCK(ch->ch_lock, lock_flags);
1008
1009         /*
1010          * NOTE: Do something with time passed in.
1011          */
1012         rc = wait_event_interruptible(un->un_flags_wait,
1013                                          ((un->un_flags & UN_EMPTY) == 0));
1014
1015         /* If ret is non-zero, user ctrl-c'ed us */
1016         if (rc)
1017                 DPR_IOCTL(("%d Drain - User ctrl c'ed\n", __LINE__));
1018
1019         return rc;
1020 }
1021
1022
1023 /* Channel lock MUST be held before calling this function! */
1024 static void cls_flush_uart_write(struct channel_t *ch)
1025 {
1026         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1027                 return;
1028
1029         writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT),
1030                                                 &ch->ch_cls_uart->isr_fcr);
1031         udelay(10);
1032
1033         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1034 }
1035
1036
1037 /* Channel lock MUST be held before calling this function! */
1038 static void cls_flush_uart_read(struct channel_t *ch)
1039 {
1040         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1041                 return;
1042
1043         /*
1044          * For complete POSIX compatibility, we should be purging the
1045          * read FIFO in the UART here.
1046          *
1047          * However, doing the statement below also incorrectly flushes
1048          * write data as well as just basically trashing the FIFO.
1049          *
1050          * I believe this is a BUG in this UART.
1051          * So for now, we will leave the code #ifdef'ed out...
1052          */
1053 #if 0
1054         writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR),
1055                                          &ch->ch_cls_uart->isr_fcr);
1056 #endif
1057         udelay(10);
1058 }
1059
1060
1061 static void cls_copy_data_from_queue_to_uart(struct channel_t *ch)
1062 {
1063         ushort head;
1064         ushort tail;
1065         int n;
1066         int qlen;
1067         uint len_written = 0;
1068         ulong lock_flags;
1069
1070         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1071                 return;
1072
1073         DGNC_LOCK(ch->ch_lock, lock_flags);
1074
1075         /* No data to write to the UART */
1076         if (ch->ch_w_tail == ch->ch_w_head) {
1077                 DGNC_UNLOCK(ch->ch_lock, lock_flags);
1078                 return;
1079         }
1080
1081         /* If port is "stopped", don't send any data to the UART */
1082         if ((ch->ch_flags & CH_FORCED_STOP) ||
1083                                  (ch->ch_flags & CH_BREAK_SENDING)) {
1084                 DGNC_UNLOCK(ch->ch_lock, lock_flags);
1085                 return;
1086         }
1087
1088         if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM))) {
1089                 DGNC_UNLOCK(ch->ch_lock, lock_flags);
1090                 return;
1091         }
1092
1093         n = 32;
1094
1095         /* cache head and tail of queue */
1096         head = ch->ch_w_head & WQUEUEMASK;
1097         tail = ch->ch_w_tail & WQUEUEMASK;
1098         qlen = (head - tail) & WQUEUEMASK;
1099
1100         /* Find minimum of the FIFO space, versus queue length */
1101         n = min(n, qlen);
1102
1103         while (n > 0) {
1104
1105                 /*
1106                  * If RTS Toggle mode is on, turn on RTS now if not already set,
1107                  * and make sure we get an event when the data transfer has
1108                  * completed.
1109                  */
1110                 if (ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE) {
1111                         if (!(ch->ch_mostat & UART_MCR_RTS)) {
1112                                 ch->ch_mostat |= (UART_MCR_RTS);
1113                                 cls_assert_modem_signals(ch);
1114                         }
1115                         ch->ch_tun.un_flags |= (UN_EMPTY);
1116                 }
1117
1118                 /*
1119                  * If DTR Toggle mode is on, turn on DTR now if not already set,
1120                  * and make sure we get an event when the data transfer has
1121                  * completed.
1122                  */
1123                 if (ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE) {
1124                         if (!(ch->ch_mostat & UART_MCR_DTR)) {
1125                                 ch->ch_mostat |= (UART_MCR_DTR);
1126                                 cls_assert_modem_signals(ch);
1127                         }
1128                         ch->ch_tun.un_flags |= (UN_EMPTY);
1129                 }
1130                 writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_cls_uart->txrx);
1131                 dgnc_sniff_nowait_nolock(ch, "UART WRITE",
1132                                             ch->ch_wqueue + ch->ch_w_tail, 1);
1133                 DPR_WRITE(("Tx data: %x\n", ch->ch_wqueue[ch->ch_w_tail]));
1134                 ch->ch_w_tail++;
1135                 ch->ch_w_tail &= WQUEUEMASK;
1136                 ch->ch_txcount++;
1137                 len_written++;
1138                 n--;
1139         }
1140
1141         if (len_written > 0)
1142                 ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1143
1144         DGNC_UNLOCK(ch->ch_lock, lock_flags);
1145
1146         return;
1147 }
1148
1149
1150 static void cls_parse_modem(struct channel_t *ch, uchar signals)
1151 {
1152         uchar msignals = signals;
1153         ulong lock_flags;
1154
1155         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1156                 return;
1157
1158         DPR_MSIGS(("cls_parse_modem: port: %d signals: %d\n",
1159                                          ch->ch_portnum, msignals));
1160
1161         /*
1162          * Do altpin switching. Altpin switches DCD and DSR.
1163          * This prolly breaks DSRPACE, so we should be more clever here.
1164          */
1165         DGNC_LOCK(ch->ch_lock, lock_flags);
1166         if (ch->ch_digi.digi_flags & DIGI_ALTPIN) {
1167                 uchar mswap = signals;
1168                 if (mswap & UART_MSR_DDCD) {
1169                         msignals &= ~UART_MSR_DDCD;
1170                         msignals |= UART_MSR_DDSR;
1171                 }
1172                 if (mswap & UART_MSR_DDSR) {
1173                         msignals &= ~UART_MSR_DDSR;
1174                         msignals |= UART_MSR_DDCD;
1175                 }
1176                 if (mswap & UART_MSR_DCD) {
1177                         msignals &= ~UART_MSR_DCD;
1178                         msignals |= UART_MSR_DSR;
1179                 }
1180                 if (mswap & UART_MSR_DSR) {
1181                         msignals &= ~UART_MSR_DSR;
1182                         msignals |= UART_MSR_DCD;
1183                 }
1184         }
1185         DGNC_UNLOCK(ch->ch_lock, lock_flags);
1186
1187         /*
1188          * Scrub off lower bits. They signify delta's, which I don't
1189          * care about
1190          */
1191         signals &= 0xf0;
1192
1193         DGNC_LOCK(ch->ch_lock, lock_flags);
1194         if (msignals & UART_MSR_DCD)
1195                 ch->ch_mistat |= UART_MSR_DCD;
1196         else
1197                 ch->ch_mistat &= ~UART_MSR_DCD;
1198
1199         if (msignals & UART_MSR_DSR)
1200                 ch->ch_mistat |= UART_MSR_DSR;
1201         else
1202                 ch->ch_mistat &= ~UART_MSR_DSR;
1203
1204         if (msignals & UART_MSR_RI)
1205                 ch->ch_mistat |= UART_MSR_RI;
1206         else
1207                 ch->ch_mistat &= ~UART_MSR_RI;
1208
1209         if (msignals & UART_MSR_CTS)
1210                 ch->ch_mistat |= UART_MSR_CTS;
1211         else
1212                 ch->ch_mistat &= ~UART_MSR_CTS;
1213         DGNC_UNLOCK(ch->ch_lock, lock_flags);
1214
1215
1216         DPR_MSIGS((
1217                 "Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
1218                 ch->ch_portnum,
1219                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
1220                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
1221                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
1222                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
1223                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
1224                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD)));
1225 }
1226
1227
1228 /* Make the UART raise any of the output signals we want up */
1229 static void cls_assert_modem_signals(struct channel_t *ch)
1230 {
1231         uchar out;
1232
1233         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1234                 return;
1235
1236         out = ch->ch_mostat;
1237
1238         if (ch->ch_flags & CH_LOOPBACK)
1239                 out |= UART_MCR_LOOP;
1240
1241         writeb(out, &ch->ch_cls_uart->mcr);
1242
1243         /* Give time for the UART to actually drop the signals */
1244         udelay(10);
1245 }
1246
1247
1248 static void cls_send_start_character(struct channel_t *ch)
1249 {
1250         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1251                 return;
1252
1253         if (ch->ch_startc != _POSIX_VDISABLE) {
1254                 ch->ch_xon_sends++;
1255                 writeb(ch->ch_startc, &ch->ch_cls_uart->txrx);
1256         }
1257 }
1258
1259
1260 static void cls_send_stop_character(struct channel_t *ch)
1261 {
1262         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1263                 return;
1264
1265         if (ch->ch_stopc != _POSIX_VDISABLE) {
1266                 ch->ch_xoff_sends++;
1267                 writeb(ch->ch_stopc, &ch->ch_cls_uart->txrx);
1268         }
1269 }
1270
1271
1272 /* Inits UART */
1273 static void cls_uart_init(struct channel_t *ch)
1274 {
1275         uchar lcrb = readb(&ch->ch_cls_uart->lcr);
1276         uchar isr_fcr = 0;
1277
1278         writeb(0, &ch->ch_cls_uart->ier);
1279
1280         /*
1281          * The Enhanced Register Set may only be accessed when
1282          * the Line Control Register is set to 0xBFh.
1283          */
1284         writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
1285
1286         isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
1287
1288         /* Turn on Enhanced/Extended controls */
1289         isr_fcr |= (UART_EXAR654_EFR_ECB);
1290
1291         writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
1292
1293         /* Write old LCR value back out, which turns enhanced access off */
1294         writeb(lcrb, &ch->ch_cls_uart->lcr);
1295
1296         /* Clear out UART and FIFO */
1297         readb(&ch->ch_cls_uart->txrx);
1298
1299         writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT),
1300                                                  &ch->ch_cls_uart->isr_fcr);
1301         udelay(10);
1302
1303         ch->ch_flags |= (CH_FIFO_ENABLED | CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1304
1305         readb(&ch->ch_cls_uart->lsr);
1306         readb(&ch->ch_cls_uart->msr);
1307 }
1308
1309
1310 /*
1311  * Turns off UART.
1312  */
1313 static void cls_uart_off(struct channel_t *ch)
1314 {
1315         writeb(0, &ch->ch_cls_uart->ier);
1316 }
1317
1318
1319 /*
1320  * cls_get_uarts_bytes_left.
1321  * Returns 0 is nothing left in the FIFO, returns 1 otherwise.
1322  *
1323  * The channel lock MUST be held by the calling function.
1324  */
1325 static uint cls_get_uart_bytes_left(struct channel_t *ch)
1326 {
1327         uchar left = 0;
1328         uchar lsr = 0;
1329
1330         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1331                 return 0;
1332
1333         lsr = readb(&ch->ch_cls_uart->lsr);
1334
1335         /* Determine whether the Transmitter is empty or not */
1336         if (!(lsr & UART_LSR_TEMT)) {
1337                 if (ch->ch_flags & CH_TX_FIFO_EMPTY)
1338                         tasklet_schedule(&ch->ch_bd->helper_tasklet);
1339                 left = 1;
1340         } else {
1341                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1342                 left = 0;
1343         }
1344
1345         return left;
1346 }
1347
1348
1349 /*
1350  * cls_send_break.
1351  * Starts sending a break thru the UART.
1352  *
1353  * The channel lock MUST be held by the calling function.
1354  */
1355 static void cls_send_break(struct channel_t *ch, int msecs)
1356 {
1357         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1358                 return;
1359
1360         /*
1361          * If we receive a time of 0, this means turn off the break.
1362          */
1363         if (msecs == 0) {
1364                 /* Turn break off, and unset some variables */
1365                 if (ch->ch_flags & CH_BREAK_SENDING) {
1366                         uchar temp = readb(&ch->ch_cls_uart->lcr);
1367                         writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
1368                         ch->ch_flags &= ~(CH_BREAK_SENDING);
1369                         ch->ch_stop_sending_break = 0;
1370                         DPR_IOCTL(("Finishing UART_LCR_SBC! finished: %lx\n",
1371                                                                      jiffies));
1372                 }
1373                 return;
1374         }
1375
1376         /*
1377          * Set the time we should stop sending the break.
1378          * If we are already sending a break, toss away the existing
1379          * time to stop, and use this new value instead.
1380          */
1381         ch->ch_stop_sending_break = jiffies + dgnc_jiffies_from_ms(msecs);
1382
1383         /* Tell the UART to start sending the break */
1384         if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1385                 uchar temp = readb(&ch->ch_cls_uart->lcr);
1386                 writeb((temp | UART_LCR_SBC), &ch->ch_cls_uart->lcr);
1387                 ch->ch_flags |= (CH_BREAK_SENDING);
1388                 DPR_IOCTL((
1389                         "Port %d. Starting UART_LCR_SBC! start: %lx should end: %lx\n",
1390                         ch->ch_portnum, jiffies, ch->ch_stop_sending_break));
1391         }
1392 }
1393
1394
1395 /*
1396  * cls_send_immediate_char.
1397  * Sends a specific character as soon as possible to the UART,
1398  * jumping over any bytes that might be in the write queue.
1399  *
1400  * The channel lock MUST be held by the calling function.
1401  */
1402 static void cls_send_immediate_char(struct channel_t *ch, unsigned char c)
1403 {
1404         if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
1405                 return;
1406
1407         writeb(c, &ch->ch_cls_uart->txrx);
1408 }
1409
1410 static void cls_vpd(struct dgnc_board *brd)
1411 {
1412         ulong           vpdbase;        /* Start of io base of the card */
1413         u8 __iomem           *re_map_vpdbase;/* Remapped memory of the card */
1414         int i = 0;
1415
1416
1417         vpdbase = pci_resource_start(brd->pdev, 3);
1418
1419         /* No VPD */
1420         if (!vpdbase)
1421                 return;
1422
1423         re_map_vpdbase = ioremap(vpdbase, 0x400);
1424
1425         if (!re_map_vpdbase)
1426                 return;
1427
1428         /* Store the VPD into our buffer */
1429         for (i = 0; i < 0x40; i++) {
1430                 brd->vpd[i] = readb(re_map_vpdbase + i);
1431                 pr_info("%x ", brd->vpd[i]);
1432         }
1433         pr_info("\n");
1434
1435         if (re_map_vpdbase)
1436                 iounmap(re_map_vpdbase);
1437 }
1438