drivers/serial/dz.c

   1 /*
   2  * dz.c: Serial port driver for DECStations equiped
   3  *       with the DZ chipset.
   4  *
   5  * Copyright (C) 1998 Olivier A. D. Lebaillif
   6  *
   7  * Email: olivier.lebaillif@ifrsys.com
   8  *
   9  * [31-AUG-98] triemer
  10  * Changed IRQ to use Harald's dec internals interrupts.h
  11  * removed base_addr code - moving address assignment to setup.c
  12  * Changed name of dz_init to rs_init to be consistent with tc code
  13  * [13-NOV-98] triemer fixed code to receive characters
  14  *    after patches by harald to irq code.
  15  * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout
  16  *            field from "current" - somewhere between 2.1.121 and 2.1.131
  17  Qua Jun 27 15:02:26 BRT 2001
  18  * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups
  19  *
  20  * Parts (C) 1999 David Airlie, airlied@linux.ie
  21  * [07-SEP-99] Bugfixes
  22  *
  23  * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk>
  24  * Converted to new serial core
  25  */
  26
  27 #undef DEBUG_DZ
  28
  29 #include <linux/module.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/init.h>
  32 #include <linux/console.h>
  33 #include <linux/tty.h>
  34 #include <linux/tty_flip.h>
  35 #include <linux/serial_core.h>
  36 #include <linux/serial.h>
  37
  38 #include <asm/bootinfo.h>
  39 #include <asm/dec/interrupts.h>
  40 #include <asm/dec/kn01.h>
  41 #include <asm/dec/kn02.h>
  42 #include <asm/dec/machtype.h>
  43 #include <asm/dec/prom.h>
  44 #include <asm/irq.h>
  45 #include <asm/system.h>
  46 #include <asm/uaccess.h>
  47
  48 #define CONSOLE_LINE (3)        /* for definition of struct console */
  49
  50 #include "dz.h"
  51
  52 #define DZ_INTR_DEBUG 1
  53
  54 static char *dz_name = "DECstation DZ serial driver version ";
  55 static char *dz_version = "1.02";
  56
  57 struct dz_port {
  58         struct uart_port        port;
  59         unsigned int            cflag;
  60 };
  61
  62 static struct dz_port dz_ports[DZ_NB_PORT];
  63
  64 #ifdef DEBUG_DZ
  65 /*
  66  * debugging code to send out chars via prom
  67  */
  68 static void debug_console(const char *s, int count)
  69 {
  70         unsigned i;
  71
  72         for (i = 0; i < count; i++) {
  73                 if (*s == 10)
  74                         prom_printf("%c", 13);
  75                 prom_printf("%c", *s++);
  76         }
  77 }
  78 #endif
  79
  80 /*
  81  * ------------------------------------------------------------
  82  * dz_in () and dz_out ()
  83  *
  84  * These routines are used to access the registers of the DZ
  85  * chip, hiding relocation differences between implementation.
  86  * ------------------------------------------------------------
  87  */
  88
  89 static inline unsigned short dz_in(struct dz_port *dport, unsigned offset)
  90 {
  91         volatile unsigned short *addr =
  92                 (volatile unsigned short *) (dport->port.membase + offset);
  93         return *addr;
  94 }
  95
  96 static inline void dz_out(struct dz_port *dport, unsigned offset,
  97                           unsigned short value)
  98 {
  99         volatile unsigned short *addr =
 100                 (volatile unsigned short *) (dport->port.membase + offset);
 101         *addr = value;
 102 }
 103
 104 /*
 105  * ------------------------------------------------------------
 106  * rs_stop () and rs_start ()
 107  *
 108  * These routines are called before setting or resetting
 109  * tty->stopped. They enable or disable transmitter interrupts,
 110  * as necessary.
 111  * ------------------------------------------------------------
 112  */
 113
 114 static void dz_stop_tx(struct uart_port *uport)
 115 {
 116         struct dz_port *dport = (struct dz_port *)uport;
 117         unsigned short tmp, mask = 1 << dport->port.line;
 118         unsigned long flags;
 119
 120         spin_lock_irqsave(&dport->port.lock, flags);
 121         tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
 122         tmp &= ~mask;                   /* clear the TX flag */
 123         dz_out(dport, DZ_TCR, tmp);
 124         spin_unlock_irqrestore(&dport->port.lock, flags);
 125 }
 126
 127 static void dz_start_tx(struct uart_port *uport)
 128 {
 129         struct dz_port *dport = (struct dz_port *)uport;
 130         unsigned short tmp, mask = 1 << dport->port.line;
 131         unsigned long flags;
 132
 133         spin_lock_irqsave(&dport->port.lock, flags);
 134         tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
 135         tmp |= mask;                    /* set the TX flag */
 136         dz_out(dport, DZ_TCR, tmp);
 137         spin_unlock_irqrestore(&dport->port.lock, flags);
 138 }
 139
 140 static void dz_stop_rx(struct uart_port *uport)
 141 {
 142         struct dz_port *dport = (struct dz_port *)uport;
 143         unsigned long flags;
 144
 145         spin_lock_irqsave(&dport->port.lock, flags);
 146         dport->cflag &= ~DZ_CREAD;
 147         dz_out(dport, DZ_LPR, dport->cflag);
 148         spin_unlock_irqrestore(&dport->port.lock, flags);
 149 }
 150
 151 static void dz_enable_ms(struct uart_port *port)
 152 {
 153         /* nothing to do */
 154 }
 155
 156 /*
 157  * ------------------------------------------------------------
 158  * Here starts the interrupt handling routines.  All of the
 159  * following subroutines are declared as inline and are folded
 160  * into dz_interrupt.  They were separated out for readability's
 161  * sake.
 162  *
 163  * Note: rs_interrupt() is a "fast" interrupt, which means that it
 164  * runs with interrupts turned off.  People who may want to modify
 165  * rs_interrupt() should try to keep the interrupt handler as fast as
 166  * possible.  After you are done making modifications, it is not a bad
 167  * idea to do:
 168  *
 169  *      make drivers/serial/dz.s
 170  *
 171  * and look at the resulting assemble code in dz.s.
 172  *
 173  * ------------------------------------------------------------
 174  */
 175
 176 /*
 177  * ------------------------------------------------------------
 178  * receive_char ()
 179  *
 180  * This routine deals with inputs from any lines.
 181  * ------------------------------------------------------------
 182  */
 183 static inline void dz_receive_chars(struct dz_port *dport)
 184 {
 185         struct tty_struct *tty = NULL;
 186         struct uart_icount *icount;
 187         int ignore = 0;
 188         unsigned short status, tmp;
 189         unsigned char ch, flag;
 190
 191         /* this code is going to be a problem...
 192            the call to tty_flip_buffer is going to need
 193            to be rethought...
 194          */
 195         do {
 196                 status = dz_in(dport, DZ_RBUF);
 197
 198                 /* punt so we don't get duplicate characters */
 199                 if (!(status & DZ_DVAL))
 200                         goto ignore_char;
 201
 202
 203                 ch = UCHAR(status);     /* grab the char */
 204                 flag = TTY_NORMAL;
 205
 206 #if 0
 207                 if (info->is_console) {
 208                         if (ch == 0)
 209                                 return;         /* it's a break ... */
 210                 }
 211 #endif
 212
 213                 tty = dport->port.info->tty;/* now tty points to the proper dev */
 214                 icount = &dport->port.icount;
 215
 216                 if (!tty)
 217                         break;
 218
 219                 icount->rx++;
 220
 221                 /* keep track of the statistics */
 222                 if (status & (DZ_OERR | DZ_FERR | DZ_PERR)) {
 223                         if (status & DZ_PERR)   /* parity error */
 224                                 icount->parity++;
 225                         else if (status & DZ_FERR)      /* frame error */
 226                                 icount->frame++;
 227                         if (status & DZ_OERR)   /* overrun error */
 228                                 icount->overrun++;
 229
 230                         /*  check to see if we should ignore the character
 231                            and mask off conditions that should be ignored
 232                          */
 233
 234                         if (status & dport->port.ignore_status_mask) {
 235                                 if (++ignore > 100)
 236                                         break;
 237                                 goto ignore_char;
 238                         }
 239                         /* mask off the error conditions we want to ignore */
 240                         tmp = status & dport->port.read_status_mask;
 241
 242                         if (tmp & DZ_PERR) {
 243                                 flag = TTY_PARITY;
 244 #ifdef DEBUG_DZ
 245                                 debug_console("PERR\n", 5);
 246 #endif
 247                         } else if (tmp & DZ_FERR) {
 248                                 flag = TTY_FRAME;
 249 #ifdef DEBUG_DZ
 250                                 debug_console("FERR\n", 5);
 251 #endif
 252                         }
 253                         if (tmp & DZ_OERR) {
 254 #ifdef DEBUG_DZ
 255                                 debug_console("OERR\n", 5);
 256 #endif
 257                                 tty_insert_flip_char(tty, ch, flag);
 258                                 ch = 0;
 259                                 flag = TTY_OVERRUN;
 260                         }
 261                 }
 262                 tty_insert_flip_char(tty, ch, flag);
 263               ignore_char:
 264                         ;
 265         } while (status & DZ_DVAL);
 266
 267         if (tty)
 268                 tty_flip_buffer_push(tty);
 269 }
 270
 271 /*
 272  * ------------------------------------------------------------
 273  * transmit_char ()
 274  *
 275  * This routine deals with outputs to any lines.
 276  * ------------------------------------------------------------
 277  */
 278 static inline void dz_transmit_chars(struct dz_port *dport)
 279 {
 280         struct circ_buf *xmit = &dport->port.info->xmit;
 281         unsigned char tmp;
 282
 283         if (dport->port.x_char) {       /* XON/XOFF chars */
 284                 dz_out(dport, DZ_TDR, dport->port.x_char);
 285                 dport->port.icount.tx++;
 286                 dport->port.x_char = 0;
 287                 return;
 288         }
 289         /* if nothing to do or stopped or hardware stopped */
 290         if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
 291                 dz_stop_tx(&dport->port);
 292                 return;
 293         }
 294
 295         /*
 296          * if something to do ... (rember the dz has no output fifo so we go
 297          * one char at a time :-<
 298          */
 299         tmp = xmit->buf[xmit->tail];
 300         xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
 301         dz_out(dport, DZ_TDR, tmp);
 302         dport->port.icount.tx++;
 303
 304         if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
 305                 uart_write_wakeup(&dport->port);
 306
 307         /* Are we done */
 308         if (uart_circ_empty(xmit))
 309                 dz_stop_tx(&dport->port);
 310 }
 311
 312 /*
 313  * ------------------------------------------------------------
 314  * check_modem_status ()
 315  *
 316  * Only valid for the MODEM line duh !
 317  * ------------------------------------------------------------
 318  */
 319 static inline void check_modem_status(struct dz_port *dport)
 320 {
 321         unsigned short status;
 322
 323         /* if not ne modem line just return */
 324         if (dport->port.line != DZ_MODEM)
 325                 return;
 326
 327         status = dz_in(dport, DZ_MSR);
 328
 329         /* it's easy, since DSR2 is the only bit in the register */
 330         if (status)
 331                 dport->port.icount.dsr++;
 332 }
 333
 334 /*
 335  * ------------------------------------------------------------
 336  * dz_interrupt ()
 337  *
 338  * this is the main interrupt routine for the DZ chip.
 339  * It deals with the multiple ports.
 340  * ------------------------------------------------------------
 341  */
 342 static irqreturn_t dz_interrupt(int irq, void *dev, struct pt_regs *regs)
 343 {
 344         struct dz_port *dport;
 345         unsigned short status;
 346
 347         /* get the reason why we just got an irq */
 348         status = dz_in((struct dz_port *)dev, DZ_CSR);
 349         dport = &dz_ports[LINE(status)];
 350
 351         if (status & DZ_RDONE)
 352                 dz_receive_chars(dport);
 353
 354         if (status & DZ_TRDY)
 355                 dz_transmit_chars(dport);
 356
 357         /* FIXME: what about check modem status??? --rmk */
 358
 359         return IRQ_HANDLED;
 360 }
 361
 362 /*
 363  * -------------------------------------------------------------------
 364  * Here ends the DZ interrupt routines.
 365  * -------------------------------------------------------------------
 366  */
 367
 368 static unsigned int dz_get_mctrl(struct uart_port *uport)
 369 {
 370         struct dz_port *dport = (struct dz_port *)uport;
 371         unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
 372
 373         if (dport->port.line == DZ_MODEM) {
 374                 /*
 375                  * CHECKME: This is a guess from the other code... --rmk
 376                  */
 377                 if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
 378                         mctrl &= ~TIOCM_DSR;
 379         }
 380
 381         return mctrl;
 382 }
 383
 384 static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
 385 {
 386         struct dz_port *dport = (struct dz_port *)uport;
 387         unsigned short tmp;
 388
 389         if (dport->port.line == DZ_MODEM) {
 390                 tmp = dz_in(dport, DZ_TCR);
 391                 if (mctrl & TIOCM_DTR)
 392                         tmp &= ~DZ_MODEM_DTR;
 393                 else
 394                         tmp |= DZ_MODEM_DTR;
 395                 dz_out(dport, DZ_TCR, tmp);
 396         }
 397 }
 398
 399 /*
 400  * -------------------------------------------------------------------
 401  * startup ()
 402  *
 403  * various initialization tasks
 404  * -------------------------------------------------------------------
 405  */
 406 static int dz_startup(struct uart_port *uport)
 407 {
 408         struct dz_port *dport = (struct dz_port *)uport;
 409         unsigned long flags;
 410         unsigned short tmp;
 411
 412         /* The dz lines for the mouse/keyboard must be
 413          * opened using their respective drivers.
 414          */
 415         if ((dport->port.line == DZ_KEYBOARD) ||
 416             (dport->port.line == DZ_MOUSE))
 417                 return -ENODEV;
 418
 419         spin_lock_irqsave(&dport->port.lock, flags);
 420
 421         /* enable the interrupt and the scanning */
 422         tmp = dz_in(dport, DZ_CSR);
 423         tmp |= DZ_RIE | DZ_TIE | DZ_MSE;
 424         dz_out(dport, DZ_CSR, tmp);
 425
 426         spin_unlock_irqrestore(&dport->port.lock, flags);
 427
 428         return 0;
 429 }
 430
 431 /*
 432  * -------------------------------------------------------------------
 433  * shutdown ()
 434  *
 435  * This routine will shutdown a serial port; interrupts are disabled, and
 436  * DTR is dropped if the hangup on close termio flag is on.
 437  * -------------------------------------------------------------------
 438  */
 439 static void dz_shutdown(struct uart_port *uport)
 440 {
 441         dz_stop_tx(uport);
 442 }
 443
 444 /*
 445  * get_lsr_info - get line status register info
 446  *
 447  * Purpose: Let user call ioctl() to get info when the UART physically
 448  *          is emptied.  On bus types like RS485, the transmitter must
 449  *          release the bus after transmitting. This must be done when
 450  *          the transmit shift register is empty, not be done when the
 451  *          transmit holding register is empty.  This functionality
 452  *          allows an RS485 driver to be written in user space.
 453  */
 454 static unsigned int dz_tx_empty(struct uart_port *uport)
 455 {
 456         struct dz_port *dport = (struct dz_port *)uport;
 457         unsigned short status = dz_in(dport, DZ_LPR);
 458
 459         /* FIXME: this appears to be obviously broken --rmk. */
 460         return status ? TIOCSER_TEMT : 0;
 461 }
 462
 463 static void dz_break_ctl(struct uart_port *uport, int break_state)
 464 {
 465         struct dz_port *dport = (struct dz_port *)uport;
 466         unsigned long flags;
 467         unsigned short tmp, mask = 1 << uport->line;
 468
 469         spin_lock_irqsave(&uport->lock, flags);
 470         tmp = dz_in(dport, DZ_TCR);
 471         if (break_state)
 472                 tmp |= mask;
 473         else
 474                 tmp &= ~mask;
 475         dz_out(dport, DZ_TCR, tmp);
 476         spin_unlock_irqrestore(&uport->lock, flags);
 477 }
 478
 479 static void dz_set_termios(struct uart_port *uport, struct termios *termios,
 480                            struct termios *old_termios)
 481 {
 482         struct dz_port *dport = (struct dz_port *)uport;
 483         unsigned long flags;
 484         unsigned int cflag, baud;
 485
 486         cflag = dport->port.line;
 487
 488         switch (termios->c_cflag & CSIZE) {
 489         case CS5:
 490                 cflag |= DZ_CS5;
 491                 break;
 492         case CS6:
 493                 cflag |= DZ_CS6;
 494                 break;
 495         case CS7:
 496                 cflag |= DZ_CS7;
 497                 break;
 498         case CS8:
 499         default:
 500                 cflag |= DZ_CS8;
 501         }
 502
 503         if (termios->c_cflag & CSTOPB)
 504                 cflag |= DZ_CSTOPB;
 505         if (termios->c_cflag & PARENB)
 506                 cflag |= DZ_PARENB;
 507         if (termios->c_cflag & PARODD)
 508                 cflag |= DZ_PARODD;
 509
 510         baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600);
 511         switch (baud) {
 512         case 50:
 513                 cflag |= DZ_B50;
 514                 break;
 515         case 75:
 516                 cflag |= DZ_B75;
 517                 break;
 518         case 110:
 519                 cflag |= DZ_B110;
 520                 break;
 521         case 134:
 522                 cflag |= DZ_B134;
 523                 break;
 524         case 150:
 525                 cflag |= DZ_B150;
 526                 break;
 527         case 300:
 528                 cflag |= DZ_B300;
 529                 break;
 530         case 600:
 531                 cflag |= DZ_B600;
 532                 break;
 533         case 1200:
 534                 cflag |= DZ_B1200;
 535                 break;
 536         case 1800:
 537                 cflag |= DZ_B1800;
 538                 break;
 539         case 2000:
 540                 cflag |= DZ_B2000;
 541                 break;
 542         case 2400:
 543                 cflag |= DZ_B2400;
 544                 break;
 545         case 3600:
 546                 cflag |= DZ_B3600;
 547                 break;
 548         case 4800:
 549                 cflag |= DZ_B4800;
 550                 break;
 551         case 7200:
 552                 cflag |= DZ_B7200;
 553                 break;
 554         case 9600:
 555         default:
 556                 cflag |= DZ_B9600;
 557         }
 558
 559         if (termios->c_cflag & CREAD)
 560                 cflag |= DZ_RXENAB;
 561
 562         spin_lock_irqsave(&dport->port.lock, flags);
 563
 564         dz_out(dport, DZ_LPR, cflag);
 565         dport->cflag = cflag;
 566
 567         /* setup accept flag */
 568         dport->port.read_status_mask = DZ_OERR;
 569         if (termios->c_iflag & INPCK)
 570                 dport->port.read_status_mask |= DZ_FERR | DZ_PERR;
 571
 572         /* characters to ignore */
 573         uport->ignore_status_mask = 0;
 574         if (termios->c_iflag & IGNPAR)
 575                 dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR;
 576
 577         spin_unlock_irqrestore(&dport->port.lock, flags);
 578 }
 579
 580 static const char *dz_type(struct uart_port *port)
 581 {
 582         return "DZ";
 583 }
 584
 585 static void dz_release_port(struct uart_port *port)
 586 {
 587         /* nothing to do */
 588 }
 589
 590 static int dz_request_port(struct uart_port *port)
 591 {
 592         return 0;
 593 }
 594
 595 static void dz_config_port(struct uart_port *port, int flags)
 596 {
 597         if (flags & UART_CONFIG_TYPE)
 598                 port->type = PORT_DZ;
 599 }
 600
 601 /*
 602  * verify the new serial_struct (for TIOCSSERIAL).
 603  */
 604 static int dz_verify_port(struct uart_port *port, struct serial_struct *ser)
 605 {
 606         int ret = 0;
 607         if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ)
 608                 ret = -EINVAL;
 609         if (ser->irq != port->irq)
 610                 ret = -EINVAL;
 611         return ret;
 612 }
 613
 614 static struct uart_ops dz_ops = {
 615         .tx_empty       = dz_tx_empty,
 616         .get_mctrl      = dz_get_mctrl,
 617         .set_mctrl      = dz_set_mctrl,
 618         .stop_tx        = dz_stop_tx,
 619         .start_tx       = dz_start_tx,
 620         .stop_rx        = dz_stop_rx,
 621         .enable_ms      = dz_enable_ms,
 622         .break_ctl      = dz_break_ctl,
 623         .startup        = dz_startup,
 624         .shutdown       = dz_shutdown,
 625         .set_termios    = dz_set_termios,
 626         .type           = dz_type,
 627         .release_port   = dz_release_port,
 628         .request_port   = dz_request_port,
 629         .config_port    = dz_config_port,
 630         .verify_port    = dz_verify_port,
 631 };
 632
 633 static void __init dz_init_ports(void)
 634 {
 635         static int first = 1;
 636         struct dz_port *dport;
 637         unsigned long base;
 638         int i;
 639
 640         if (!first)
 641                 return;
 642         first = 0;
 643
 644         if (mips_machtype == MACH_DS23100 ||
 645             mips_machtype == MACH_DS5100)
 646                 base = CKSEG1ADDR(KN01_SLOT_BASE + KN01_DZ11);
 647         else
 648                 base = CKSEG1ADDR(KN02_SLOT_BASE + KN02_DZ11);
 649
 650         for (i = 0, dport = dz_ports; i < DZ_NB_PORT; i++, dport++) {
 651                 spin_lock_init(&dport->port.lock);
 652                 dport->port.membase     = (char *) base;
 653                 dport->port.iotype      = UPIO_PORT;
 654                 dport->port.irq         = dec_interrupt[DEC_IRQ_DZ11];
 655                 dport->port.line        = i;
 656                 dport->port.fifosize    = 1;
 657                 dport->port.ops         = &dz_ops;
 658                 dport->port.flags       = UPF_BOOT_AUTOCONF;
 659         }
 660 }
 661
 662 static void dz_reset(struct dz_port *dport)
 663 {
 664         dz_out(dport, DZ_CSR, DZ_CLR);
 665
 666         while (dz_in(dport, DZ_CSR) & DZ_CLR);
 667                 /* FIXME: cpu_relax? */
 668
 669         iob();
 670
 671         /* enable scanning */
 672         dz_out(dport, DZ_CSR, DZ_MSE);
 673 }
 674
 675 #ifdef CONFIG_SERIAL_DZ_CONSOLE
 676 static void dz_console_putchar(struct uart_port *uport, int ch)
 677 {
 678         struct dz_port *dport = (struct dz_port *)uport;
 679         unsigned long flags;
 680         int loops = 2500;
 681         unsigned short tmp = (unsigned char)ch;
 682         /* this code sends stuff out to serial device - spinning its
 683            wheels and waiting. */
 684
 685         spin_lock_irqsave(&dport->port.lock, flags);
 686
 687         /* spin our wheels */
 688         while (((dz_in(dport, DZ_CSR) & DZ_TRDY) != DZ_TRDY) && loops--)
 689                 /* FIXME: cpu_relax, udelay? --rmk */
 690                 ;
 691
 692         /* Actually transmit the character. */
 693         dz_out(dport, DZ_TDR, tmp);
 694
 695         spin_unlock_irqrestore(&dport->port.lock, flags);
 696 }
 697
 698 /*
 699  * -------------------------------------------------------------------
 700  * dz_console_print ()
 701  *
 702  * dz_console_print is registered for printk.
 703  * The console must be locked when we get here.
 704  * -------------------------------------------------------------------
 705  */
 706 static void dz_console_print(struct console *cons,
 707                              const char *str,
 708                              unsigned int count)
 709 {
 710         struct dz_port *dport = &dz_ports[CONSOLE_LINE];
 711 #ifdef DEBUG_DZ
 712         prom_printf((char *) str);
 713 #endif
 714         uart_console_write(&dport->port, str, count, dz_console_putchar);
 715 }
 716
 717 static int __init dz_console_setup(struct console *co, char *options)
 718 {
 719         struct dz_port *dport = &dz_ports[CONSOLE_LINE];
 720         int baud = 9600;
 721         int bits = 8;
 722         int parity = 'n';
 723         int flow = 'n';
 724         int ret;
 725         unsigned short mask, tmp;
 726
 727         if (options)
 728                 uart_parse_options(options, &baud, &parity, &bits, &flow);
 729
 730         dz_reset(dport);
 731
 732         ret = uart_set_options(&dport->port, co, baud, parity, bits, flow);
 733         if (ret == 0) {
 734                 mask = 1 << dport->port.line;
 735                 tmp = dz_in(dport, DZ_TCR);     /* read the TX flag */
 736                 if (!(tmp & mask)) {
 737                         tmp |= mask;            /* set the TX flag */
 738                         dz_out(dport, DZ_TCR, tmp);
 739                 }
 740         }
 741
 742         return ret;
 743 }
 744
 745 static struct console dz_sercons =
 746 {
 747         .name   = "ttyS",
 748         .write  = dz_console_print,
 749         .device = uart_console_device,
 750         .setup  = dz_console_setup,
 751         .flags  = CON_CONSDEV | CON_PRINTBUFFER,
 752         .index  = CONSOLE_LINE,
 753 };
 754
 755 void __init dz_serial_console_init(void)
 756 {
 757         dz_init_ports();
 758
 759         register_console(&dz_sercons);
 760 }
 761
 762 #define SERIAL_DZ_CONSOLE       &dz_sercons
 763 #else
 764 #define SERIAL_DZ_CONSOLE       NULL
 765 #endif /* CONFIG_SERIAL_DZ_CONSOLE */
 766
 767 static struct uart_driver dz_reg = {
 768         .owner                  = THIS_MODULE,
 769         .driver_name            = "serial",
 770         .dev_name               = "ttyS%d",
 771         .major                  = TTY_MAJOR,
 772         .minor                  = 64,
 773         .nr                     = DZ_NB_PORT,
 774         .cons                   = SERIAL_DZ_CONSOLE,
 775 };
 776
 777 int __init dz_init(void)
 778 {
 779         unsigned long flags;
 780         int ret, i;
 781
 782         printk("%s%s\n", dz_name, dz_version);
 783
 784         dz_init_ports();
 785
 786         save_flags(flags);
 787         cli();
 788
 789 #ifndef CONFIG_SERIAL_DZ_CONSOLE
 790         /* reset the chip */
 791         dz_reset(&dz_ports[0]);
 792 #endif
 793
 794         /* order matters here... the trick is that flags
 795            is updated... in request_irq - to immediatedly obliterate
 796            it is unwise. */
 797         restore_flags(flags);
 798
 799         if (request_irq(dz_ports[0].port.irq, dz_interrupt,
 800                         IRQF_DISABLED, "DZ", &dz_ports[0]))
 801                 panic("Unable to register DZ interrupt");
 802
 803         ret = uart_register_driver(&dz_reg);
 804         if (ret != 0)
 805                 return ret;
 806
 807         for (i = 0; i < DZ_NB_PORT; i++)
 808                 uart_add_one_port(&dz_reg, &dz_ports[i].port);
 809
 810         return ret;
 811 }
 812
 813 MODULE_DESCRIPTION("DECstation DZ serial driver");
 814 MODULE_LICENSE("GPL");