drivers/serial/dz.c

   1 /*
   2  * dz.c: Serial port driver for DECstations equipped
   3  *       with the DZ chipset.
   4  *
   5  * Copyright (C) 1998 Olivier A. D. Lebaillif
   6  *
   7  * Email: olivier.lebaillif@ifrsys.com
   8  *
   9  * Copyright (C) 2004, 2006  Maciej W. Rozycki
  10  *
  11  * [31-AUG-98] triemer
  12  * Changed IRQ to use Harald's dec internals interrupts.h
  13  * removed base_addr code - moving address assignment to setup.c
  14  * Changed name of dz_init to rs_init to be consistent with tc code
  15  * [13-NOV-98] triemer fixed code to receive characters
  16  *    after patches by harald to irq code.
  17  * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout
  18  *            field from "current" - somewhere between 2.1.121 and 2.1.131
  19  Qua Jun 27 15:02:26 BRT 2001
  20  * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups
  21  *
  22  * Parts (C) 1999 David Airlie, airlied@linux.ie
  23  * [07-SEP-99] Bugfixes
  24  *
  25  * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk>
  26  * Converted to new serial core
  27  */
  28
  29 #undef DEBUG_DZ
  30
  31 #if defined(CONFIG_SERIAL_DZ_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  32 #define SUPPORT_SYSRQ
  33 #endif
  34
  35 #include <linux/delay.h>
  36 #include <linux/module.h>
  37 #include <linux/interrupt.h>
  38 #include <linux/init.h>
  39 #include <linux/console.h>
  40 #include <linux/sysrq.h>
  41 #include <linux/tty.h>
  42 #include <linux/tty_flip.h>
  43 #include <linux/serial_core.h>
  44 #include <linux/serial.h>
  45
  46 #include <asm/bootinfo.h>
  47 #include <asm/dec/interrupts.h>
  48 #include <asm/dec/kn01.h>
  49 #include <asm/dec/kn02.h>
  50 #include <asm/dec/machtype.h>
  51 #include <asm/dec/prom.h>
  52 #include <asm/irq.h>
  53 #include <asm/system.h>
  54 #include <asm/uaccess.h>
  55
  56 #include "dz.h"
  57
  58 static char *dz_name = "DECstation DZ serial driver version ";
  59 static char *dz_version = "1.03";
  60
  61 struct dz_port {
  62         struct uart_port        port;
  63         unsigned int            cflag;
  64 };
  65
  66 static struct dz_port dz_ports[DZ_NB_PORT];
  67
  68 /*
  69  * ------------------------------------------------------------
  70  * dz_in () and dz_out ()
  71  *
  72  * These routines are used to access the registers of the DZ
  73  * chip, hiding relocation differences between implementation.
  74  * ------------------------------------------------------------
  75  */
  76
  77 static inline unsigned short dz_in(struct dz_port *dport, unsigned offset)
  78 {
  79         volatile unsigned short *addr =
  80                 (volatile unsigned short *) (dport->port.membase + offset);
  81
  82         return *addr;
  83 }
  84
  85 static inline void dz_out(struct dz_port *dport, unsigned offset,
  86                           unsigned short value)
  87 {
  88         volatile unsigned short *addr =
  89                 (volatile unsigned short *) (dport->port.membase + offset);
  90
  91         *addr = value;
  92 }
  93
  94 /*
  95  * ------------------------------------------------------------
  96  * rs_stop () and rs_start ()
  97  *
  98  * These routines are called before setting or resetting
  99  * tty->stopped. They enable or disable transmitter interrupts,
 100  * as necessary.
 101  * ------------------------------------------------------------
 102  */
 103
 104 static void dz_stop_tx(struct uart_port *uport)
 105 {
 106         struct dz_port *dport = (struct dz_port *)uport;
 107         unsigned short tmp, mask = 1 << dport->port.line;
 108         unsigned long flags;
 109
 110         spin_lock_irqsave(&dport->port.lock, flags);
 111         tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
 112         tmp &= ~mask;                   /* clear the TX flag */
 113         dz_out(dport, DZ_TCR, tmp);
 114         spin_unlock_irqrestore(&dport->port.lock, flags);
 115 }
 116
 117 static void dz_start_tx(struct uart_port *uport)
 118 {
 119         struct dz_port *dport = (struct dz_port *)uport;
 120         unsigned short tmp, mask = 1 << dport->port.line;
 121         unsigned long flags;
 122
 123         spin_lock_irqsave(&dport->port.lock, flags);
 124         tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
 125         tmp |= mask;                    /* set the TX flag */
 126         dz_out(dport, DZ_TCR, tmp);
 127         spin_unlock_irqrestore(&dport->port.lock, flags);
 128 }
 129
 130 static void dz_stop_rx(struct uart_port *uport)
 131 {
 132         struct dz_port *dport = (struct dz_port *)uport;
 133         unsigned long flags;
 134
 135         spin_lock_irqsave(&dport->port.lock, flags);
 136         dport->cflag &= ~DZ_CREAD;
 137         dz_out(dport, DZ_LPR, dport->cflag | dport->port.line);
 138         spin_unlock_irqrestore(&dport->port.lock, flags);
 139 }
 140
 141 static void dz_enable_ms(struct uart_port *port)
 142 {
 143         /* nothing to do */
 144 }
 145
 146 /*
 147  * ------------------------------------------------------------
 148  *
 149  * Here start the interrupt handling routines.  All of the following
 150  * subroutines are declared as inline and are folded into
 151  * dz_interrupt.  They were separated out for readability's sake.
 152  *
 153  * Note: dz_interrupt() is a "fast" interrupt, which means that it
 154  * runs with interrupts turned off.  People who may want to modify
 155  * dz_interrupt() should try to keep the interrupt handler as fast as
 156  * possible.  After you are done making modifications, it is not a bad
 157  * idea to do:
 158  *
 159  *      make drivers/serial/dz.s
 160  *
 161  * and look at the resulting assemble code in dz.s.
 162  *
 163  * ------------------------------------------------------------
 164  */
 165
 166 /*
 167  * ------------------------------------------------------------
 168  * receive_char ()
 169  *
 170  * This routine deals with inputs from any lines.
 171  * ------------------------------------------------------------
 172  */
 173 static inline void dz_receive_chars(struct dz_port *dport_in)
 174 {
 175         struct dz_port *dport;
 176         struct tty_struct *tty = NULL;
 177         struct uart_icount *icount;
 178         int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
 179         unsigned short status;
 180         unsigned char ch, flag;
 181         int i;
 182
 183         while ((status = dz_in(dport_in, DZ_RBUF)) & DZ_DVAL) {
 184                 dport = &dz_ports[LINE(status)];
 185                 tty = dport->port.info->tty;    /* point to the proper dev */
 186
 187                 ch = UCHAR(status);             /* grab the char */
 188
 189                 icount = &dport->port.icount;
 190                 icount->rx++;
 191
 192                 flag = TTY_NORMAL;
 193                 if (status & DZ_FERR) {         /* frame error */
 194                         /*
 195                          * There is no separate BREAK status bit, so
 196                          * treat framing errors as BREAKs for Magic SysRq
 197                          * and SAK; normally, otherwise.
 198                          */
 199                         if (uart_handle_break(&dport->port))
 200                                 continue;
 201                         if (dport->port.flags & UPF_SAK)
 202                                 flag = TTY_BREAK;
 203                         else
 204                                 flag = TTY_FRAME;
 205                 } else if (status & DZ_OERR)    /* overrun error */
 206                         flag = TTY_OVERRUN;
 207                 else if (status & DZ_PERR)      /* parity error */
 208                         flag = TTY_PARITY;
 209
 210                 /* keep track of the statistics */
 211                 switch (flag) {
 212                 case TTY_FRAME:
 213                         icount->frame++;
 214                         break;
 215                 case TTY_PARITY:
 216                         icount->parity++;
 217                         break;
 218                 case TTY_OVERRUN:
 219                         icount->overrun++;
 220                         break;
 221                 case TTY_BREAK:
 222                         icount->brk++;
 223                         break;
 224                 default:
 225                         break;
 226                 }
 227
 228                 if (uart_handle_sysrq_char(&dport->port, ch))
 229                         continue;
 230
 231                 if ((status & dport->port.ignore_status_mask) == 0) {
 232                         uart_insert_char(&dport->port,
 233                                          status, DZ_OERR, ch, flag);
 234                         lines_rx[LINE(status)] = 1;
 235                 }
 236         }
 237         for (i = 0; i < DZ_NB_PORT; i++)
 238                 if (lines_rx[i])
 239                         tty_flip_buffer_push(dz_ports[i].port.info->tty);
 240 }
 241
 242 /*
 243  * ------------------------------------------------------------
 244  * transmit_char ()
 245  *
 246  * This routine deals with outputs to any lines.
 247  * ------------------------------------------------------------
 248  */
 249 static inline void dz_transmit_chars(struct dz_port *dport_in)
 250 {
 251         struct dz_port *dport;
 252         struct circ_buf *xmit;
 253         unsigned short status;
 254         unsigned char tmp;
 255
 256         status = dz_in(dport_in, DZ_CSR);
 257         dport = &dz_ports[LINE(status)];
 258         xmit = &dport->port.info->xmit;
 259
 260         if (dport->port.x_char) {               /* XON/XOFF chars */
 261                 dz_out(dport, DZ_TDR, dport->port.x_char);
 262                 dport->port.icount.tx++;
 263                 dport->port.x_char = 0;
 264                 return;
 265         }
 266         /* If nothing to do or stopped or hardware stopped. */
 267         if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
 268                 dz_stop_tx(&dport->port);
 269                 return;
 270         }
 271
 272         /*
 273          * If something to do... (remember the dz has no output fifo,
 274          * so we go one char at a time) :-<
 275          */
 276         tmp = xmit->buf[xmit->tail];
 277         xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
 278         dz_out(dport, DZ_TDR, tmp);
 279         dport->port.icount.tx++;
 280
 281         if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
 282                 uart_write_wakeup(&dport->port);
 283
 284         /* Are we are done. */
 285         if (uart_circ_empty(xmit))
 286                 dz_stop_tx(&dport->port);
 287 }
 288
 289 /*
 290  * ------------------------------------------------------------
 291  * check_modem_status()
 292  *
 293  * DS 3100 & 5100: Only valid for the MODEM line, duh!
 294  * DS 5000/200: Valid for the MODEM and PRINTER line.
 295  * ------------------------------------------------------------
 296  */
 297 static inline void check_modem_status(struct dz_port *dport)
 298 {
 299         /*
 300          * FIXME:
 301          * 1. No status change interrupt; use a timer.
 302          * 2. Handle the 3100/5000 as appropriate. --macro
 303          */
 304         unsigned short status;
 305
 306         /* If not the modem line just return.  */
 307         if (dport->port.line != DZ_MODEM)
 308                 return;
 309
 310         status = dz_in(dport, DZ_MSR);
 311
 312         /* it's easy, since DSR2 is the only bit in the register */
 313         if (status)
 314                 dport->port.icount.dsr++;
 315 }
 316
 317 /*
 318  * ------------------------------------------------------------
 319  * dz_interrupt ()
 320  *
 321  * this is the main interrupt routine for the DZ chip.
 322  * It deals with the multiple ports.
 323  * ------------------------------------------------------------
 324  */
 325 static irqreturn_t dz_interrupt(int irq, void *dev)
 326 {
 327         struct dz_port *dport = (struct dz_port *)dev;
 328         unsigned short status;
 329
 330         /* get the reason why we just got an irq */
 331         status = dz_in(dport, DZ_CSR);
 332
 333         if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
 334                 dz_receive_chars(dport);
 335
 336         if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
 337                 dz_transmit_chars(dport);
 338
 339         return IRQ_HANDLED;
 340 }
 341
 342 /*
 343  * -------------------------------------------------------------------
 344  * Here ends the DZ interrupt routines.
 345  * -------------------------------------------------------------------
 346  */
 347
 348 static unsigned int dz_get_mctrl(struct uart_port *uport)
 349 {
 350         /*
 351          * FIXME: Handle the 3100/5000 as appropriate. --macro
 352          */
 353         struct dz_port *dport = (struct dz_port *)uport;
 354         unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 355
 356         if (dport->port.line == DZ_MODEM) {
 357                 if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
 358                         mctrl &= ~TIOCM_DSR;
 359         }
 360
 361         return mctrl;
 362 }
 363
 364 static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
 365 {
 366         /*
 367          * FIXME: Handle the 3100/5000 as appropriate. --macro
 368          */
 369         struct dz_port *dport = (struct dz_port *)uport;
 370         unsigned short tmp;
 371
 372         if (dport->port.line == DZ_MODEM) {
 373                 tmp = dz_in(dport, DZ_TCR);
 374                 if (mctrl & TIOCM_DTR)
 375                         tmp &= ~DZ_MODEM_DTR;
 376                 else
 377                         tmp |= DZ_MODEM_DTR;
 378                 dz_out(dport, DZ_TCR, tmp);
 379         }
 380 }
 381
 382 /*
 383  * -------------------------------------------------------------------
 384  * startup ()
 385  *
 386  * various initialization tasks
 387  * -------------------------------------------------------------------
 388  */
 389 static int dz_startup(struct uart_port *uport)
 390 {
 391         struct dz_port *dport = (struct dz_port *)uport;
 392         unsigned long flags;
 393         unsigned short tmp;
 394
 395         spin_lock_irqsave(&dport->port.lock, flags);
 396
 397         /* enable the interrupt and the scanning */
 398         tmp = dz_in(dport, DZ_CSR);
 399         tmp |= DZ_RIE | DZ_TIE | DZ_MSE;
 400         dz_out(dport, DZ_CSR, tmp);
 401
 402         spin_unlock_irqrestore(&dport->port.lock, flags);
 403
 404         return 0;
 405 }
 406
 407 /*
 408  * -------------------------------------------------------------------
 409  * shutdown ()
 410  *
 411  * This routine will shutdown a serial port; interrupts are disabled, and
 412  * DTR is dropped if the hangup on close termio flag is on.
 413  * -------------------------------------------------------------------
 414  */
 415 static void dz_shutdown(struct uart_port *uport)
 416 {
 417         dz_stop_tx(uport);
 418 }
 419
 420 /*
 421  * -------------------------------------------------------------------
 422  * dz_tx_empty() -- get the transmitter empty status
 423  *
 424  * Purpose: Let user call ioctl() to get info when the UART physically
 425  *          is emptied.  On bus types like RS485, the transmitter must
 426  *          release the bus after transmitting. This must be done when
 427  *          the transmit shift register is empty, not be done when the
 428  *          transmit holding register is empty.  This functionality
 429  *          allows an RS485 driver to be written in user space.
 430  * -------------------------------------------------------------------
 431  */
 432 static unsigned int dz_tx_empty(struct uart_port *uport)
 433 {
 434         struct dz_port *dport = (struct dz_port *)uport;
 435         unsigned short tmp, mask = 1 << dport->port.line;
 436
 437         tmp = dz_in(dport, DZ_TCR);
 438         tmp &= mask;
 439
 440         return tmp ? 0 : TIOCSER_TEMT;
 441 }
 442
 443 static void dz_break_ctl(struct uart_port *uport, int break_state)
 444 {
 445         /*
 446          * FIXME: Can't access BREAK bits in TDR easily;
 447          * reuse the code for polled TX. --macro
 448          */
 449         struct dz_port *dport = (struct dz_port *)uport;
 450         unsigned long flags;
 451         unsigned short tmp, mask = 1 << dport->port.line;
 452
 453         spin_lock_irqsave(&uport->lock, flags);
 454         tmp = dz_in(dport, DZ_TCR);
 455         if (break_state)
 456                 tmp |= mask;
 457         else
 458                 tmp &= ~mask;
 459         dz_out(dport, DZ_TCR, tmp);
 460         spin_unlock_irqrestore(&uport->lock, flags);
 461 }
 462
 463 static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
 464                            struct ktermios *old_termios)
 465 {
 466         struct dz_port *dport = (struct dz_port *)uport;
 467         unsigned long flags;
 468         unsigned int cflag, baud;
 469
 470         cflag = dport->port.line;
 471
 472         switch (termios->c_cflag & CSIZE) {
 473         case CS5:
 474                 cflag |= DZ_CS5;
 475                 break;
 476         case CS6:
 477                 cflag |= DZ_CS6;
 478                 break;
 479         case CS7:
 480                 cflag |= DZ_CS7;
 481                 break;
 482         case CS8:
 483         default:
 484                 cflag |= DZ_CS8;
 485         }
 486
 487         if (termios->c_cflag & CSTOPB)
 488                 cflag |= DZ_CSTOPB;
 489         if (termios->c_cflag & PARENB)
 490                 cflag |= DZ_PARENB;
 491         if (termios->c_cflag & PARODD)
 492                 cflag |= DZ_PARODD;
 493
 494         baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600);
 495         switch (baud) {
 496         case 50:
 497                 cflag |= DZ_B50;
 498                 break;
 499         case 75:
 500                 cflag |= DZ_B75;
 501                 break;
 502         case 110:
 503                 cflag |= DZ_B110;
 504                 break;
 505         case 134:
 506                 cflag |= DZ_B134;
 507                 break;
 508         case 150:
 509                 cflag |= DZ_B150;
 510                 break;
 511         case 300:
 512                 cflag |= DZ_B300;
 513                 break;
 514         case 600:
 515                 cflag |= DZ_B600;
 516                 break;
 517         case 1200:
 518                 cflag |= DZ_B1200;
 519                 break;
 520         case 1800:
 521                 cflag |= DZ_B1800;
 522                 break;
 523         case 2000:
 524                 cflag |= DZ_B2000;
 525                 break;
 526         case 2400:
 527                 cflag |= DZ_B2400;
 528                 break;
 529         case 3600:
 530                 cflag |= DZ_B3600;
 531                 break;
 532         case 4800:
 533                 cflag |= DZ_B4800;
 534                 break;
 535         case 7200:
 536                 cflag |= DZ_B7200;
 537                 break;
 538         case 9600:
 539         default:
 540                 cflag |= DZ_B9600;
 541         }
 542
 543         if (termios->c_cflag & CREAD)
 544                 cflag |= DZ_RXENAB;
 545
 546         spin_lock_irqsave(&dport->port.lock, flags);
 547
 548         dz_out(dport, DZ_LPR, cflag | dport->port.line);
 549         dport->cflag = cflag;
 550
 551         /* setup accept flag */
 552         dport->port.read_status_mask = DZ_OERR;
 553         if (termios->c_iflag & INPCK)
 554                 dport->port.read_status_mask |= DZ_FERR | DZ_PERR;
 555
 556         /* characters to ignore */
 557         uport->ignore_status_mask = 0;
 558         if (termios->c_iflag & IGNPAR)
 559                 dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR;
 560
 561         spin_unlock_irqrestore(&dport->port.lock, flags);
 562 }
 563
 564 static const char *dz_type(struct uart_port *port)
 565 {
 566         return "DZ";
 567 }
 568
 569 static void dz_release_port(struct uart_port *port)
 570 {
 571         /* nothing to do */
 572 }
 573
 574 static int dz_request_port(struct uart_port *port)
 575 {
 576         return 0;
 577 }
 578
 579 static void dz_config_port(struct uart_port *port, int flags)
 580 {
 581         if (flags & UART_CONFIG_TYPE)
 582                 port->type = PORT_DZ;
 583 }
 584
 585 /*
 586  * verify the new serial_struct (for TIOCSSERIAL).
 587  */
 588 static int dz_verify_port(struct uart_port *port, struct serial_struct *ser)
 589 {
 590         int ret = 0;
 591         if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ)
 592                 ret = -EINVAL;
 593         if (ser->irq != port->irq)
 594                 ret = -EINVAL;
 595         return ret;
 596 }
 597
 598 static struct uart_ops dz_ops = {
 599         .tx_empty       = dz_tx_empty,
 600         .get_mctrl      = dz_get_mctrl,
 601         .set_mctrl      = dz_set_mctrl,
 602         .stop_tx        = dz_stop_tx,
 603         .start_tx       = dz_start_tx,
 604         .stop_rx        = dz_stop_rx,
 605         .enable_ms      = dz_enable_ms,
 606         .break_ctl      = dz_break_ctl,
 607         .startup        = dz_startup,
 608         .shutdown       = dz_shutdown,
 609         .set_termios    = dz_set_termios,
 610         .type           = dz_type,
 611         .release_port   = dz_release_port,
 612         .request_port   = dz_request_port,
 613         .config_port    = dz_config_port,
 614         .verify_port    = dz_verify_port,
 615 };
 616
 617 static void __init dz_init_ports(void)
 618 {
 619         static int first = 1;
 620         struct dz_port *dport;
 621         unsigned long base;
 622         int i;
 623
 624         if (!first)
 625                 return;
 626         first = 0;
 627
 628         if (mips_machtype == MACH_DS23100 ||
 629             mips_machtype == MACH_DS5100)
 630                 base = CKSEG1ADDR(KN01_SLOT_BASE + KN01_DZ11);
 631         else
 632                 base = CKSEG1ADDR(KN02_SLOT_BASE + KN02_DZ11);
 633
 634         for (i = 0, dport = dz_ports; i < DZ_NB_PORT; i++, dport++) {
 635                 spin_lock_init(&dport->port.lock);
 636                 dport->port.membase     = (char *) base;
 637                 dport->port.iotype      = UPIO_MEM;
 638                 dport->port.irq         = dec_interrupt[DEC_IRQ_DZ11];
 639                 dport->port.line        = i;
 640                 dport->port.fifosize    = 1;
 641                 dport->port.ops         = &dz_ops;
 642                 dport->port.flags       = UPF_BOOT_AUTOCONF;
 643         }
 644 }
 645
 646 static void dz_reset(struct dz_port *dport)
 647 {
 648         dz_out(dport, DZ_CSR, DZ_CLR);
 649         while (dz_in(dport, DZ_CSR) & DZ_CLR);
 650         iob();
 651
 652         /* enable scanning */
 653         dz_out(dport, DZ_CSR, DZ_MSE);
 654 }
 655
 656 #ifdef CONFIG_SERIAL_DZ_CONSOLE
 657 /*
 658  * -------------------------------------------------------------------
 659  * dz_console_putchar() -- transmit a character
 660  *
 661  * Polled transmission.  This is tricky.  We need to mask transmit
 662  * interrupts so that they do not interfere, enable the transmitter
 663  * for the line requested and then wait till the transmit scanner
 664  * requests data for this line.  But it may request data for another
 665  * line first, in which case we have to disable its transmitter and
 666  * repeat waiting till our line pops up.  Only then the character may
 667  * be transmitted.  Finally, the state of the transmitter mask is
 668  * restored.  Welcome to the world of PDP-11!
 669  * -------------------------------------------------------------------
 670  */
 671 static void dz_console_putchar(struct uart_port *uport, int ch)
 672 {
 673         struct dz_port *dport = (struct dz_port *)uport;
 674         unsigned long flags;
 675         unsigned short csr, tcr, trdy, mask;
 676         int loops = 10000;
 677
 678         spin_lock_irqsave(&dport->port.lock, flags);
 679         csr = dz_in(dport, DZ_CSR);
 680         dz_out(dport, DZ_CSR, csr & ~DZ_TIE);
 681         tcr = dz_in(dport, DZ_TCR);
 682         tcr |= 1 << dport->port.line;
 683         mask = tcr;
 684         dz_out(dport, DZ_TCR, mask);
 685         iob();
 686         spin_unlock_irqrestore(&dport->port.lock, flags);
 687
 688         while (loops--) {
 689                 trdy = dz_in(dport, DZ_CSR);
 690                 if (!(trdy & DZ_TRDY))
 691                         continue;
 692                 trdy = (trdy & DZ_TLINE) >> 8;
 693                 if (trdy == dport->port.line)
 694                         break;
 695                 mask &= ~(1 << trdy);
 696                 dz_out(dport, DZ_TCR, mask);
 697                 iob();
 698                 udelay(2);
 699         }
 700
 701         if (loops)                              /* Cannot send otherwise. */
 702                 dz_out(dport, DZ_TDR, ch);
 703
 704         dz_out(dport, DZ_TCR, tcr);
 705         dz_out(dport, DZ_CSR, csr);
 706 }
 707
 708 /*
 709  * -------------------------------------------------------------------
 710  * dz_console_print ()
 711  *
 712  * dz_console_print is registered for printk.
 713  * The console must be locked when we get here.
 714  * -------------------------------------------------------------------
 715  */
 716 static void dz_console_print(struct console *co,
 717                              const char *str,
 718                              unsigned int count)
 719 {
 720         struct dz_port *dport = &dz_ports[co->index];
 721 #ifdef DEBUG_DZ
 722         prom_printf((char *) str);
 723 #endif
 724         uart_console_write(&dport->port, str, count, dz_console_putchar);
 725 }
 726
 727 static int __init dz_console_setup(struct console *co, char *options)
 728 {
 729         struct dz_port *dport = &dz_ports[co->index];
 730         int baud = 9600;
 731         int bits = 8;
 732         int parity = 'n';
 733         int flow = 'n';
 734
 735         if (options)
 736                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 737
 738         dz_reset(dport);
 739
 740         return uart_set_options(&dport->port, co, baud, parity, bits, flow);
 741 }
 742
 743 static struct uart_driver dz_reg;
 744 static struct console dz_sercons = {
 745         .name   = "ttyS",
 746         .write  = dz_console_print,
 747         .device = uart_console_device,
 748         .setup  = dz_console_setup,
 749         .flags  = CON_PRINTBUFFER,
 750         .index  = -1,
 751         .data   = &dz_reg,
 752 };
 753
 754 static int __init dz_serial_console_init(void)
 755 {
 756         if (!IOASIC) {
 757                 dz_init_ports();
 758                 register_console(&dz_sercons);
 759                 return 0;
 760         } else
 761                 return -ENXIO;
 762 }
 763
 764 console_initcall(dz_serial_console_init);
 765
 766 #define SERIAL_DZ_CONSOLE       &dz_sercons
 767 #else
 768 #define SERIAL_DZ_CONSOLE       NULL
 769 #endif /* CONFIG_SERIAL_DZ_CONSOLE */
 770
 771 static struct uart_driver dz_reg = {
 772         .owner                  = THIS_MODULE,
 773         .driver_name            = "serial",
 774         .dev_name               = "ttyS",
 775         .major                  = TTY_MAJOR,
 776         .minor                  = 64,
 777         .nr                     = DZ_NB_PORT,
 778         .cons                   = SERIAL_DZ_CONSOLE,
 779 };
 780
 781 static int __init dz_init(void)
 782 {
 783         int ret, i;
 784
 785         if (IOASIC)
 786                 return -ENXIO;
 787
 788         printk("%s%s\n", dz_name, dz_version);
 789
 790         dz_init_ports();
 791
 792 #ifndef CONFIG_SERIAL_DZ_CONSOLE
 793         /* reset the chip */
 794         dz_reset(&dz_ports[0]);
 795 #endif
 796
 797         if (request_irq(dz_ports[0].port.irq, dz_interrupt,
 798                         IRQF_DISABLED, "DZ", &dz_ports[0]))
 799                 panic("Unable to register DZ interrupt");
 800
 801         ret = uart_register_driver(&dz_reg);
 802         if (ret != 0)
 803                 return ret;
 804
 805         for (i = 0; i < DZ_NB_PORT; i++)
 806                 uart_add_one_port(&dz_reg, &dz_ports[i].port);
 807
 808         return ret;
 809 }
 810
 811 module_init(dz_init);
 812
 813 MODULE_DESCRIPTION("DECstation DZ serial driver");
 814 MODULE_LICENSE("GPL");