arch/ia64/hp/sim/simserial.c

   1 /*
   2  * Simulated Serial Driver (fake serial)
   3  *
   4  * This driver is mostly used for bringup purposes and will go away.
   5  * It has a strong dependency on the system console. All outputs
   6  * are rerouted to the same facility as the one used by printk which, in our
   7  * case means sys_sim.c console (goes via the simulator). The code hereafter
   8  * is completely leveraged from the serial.c driver.
   9  *
  10  * Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co
  11  *      Stephane Eranian <eranian@hpl.hp.com>
  12  *      David Mosberger-Tang <davidm@hpl.hp.com>
  13  *
  14  * 02/04/00 D. Mosberger        Merged in serial.c bug fixes in rs_close().
  15  * 02/25/00 D. Mosberger        Synced up with 2.3.99pre-5 version of serial.c.
  16  * 07/30/02 D. Mosberger        Replace sti()/cli() with explicit spinlocks & local irq masking
  17  */
  18
  19 #include <linux/init.h>
  20 #include <linux/errno.h>
  21 #include <linux/sched.h>
  22 #include <linux/tty.h>
  23 #include <linux/tty_flip.h>
  24 #include <linux/major.h>
  25 #include <linux/fcntl.h>
  26 #include <linux/mm.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/slab.h>
  29 #include <linux/capability.h>
  30 #include <linux/console.h>
  31 #include <linux/module.h>
  32 #include <linux/serial.h>
  33 #include <linux/serialP.h>
  34 #include <linux/sysrq.h>
  35
  36 #include <asm/irq.h>
  37 #include <asm/hw_irq.h>
  38 #include <asm/uaccess.h>
  39
  40 #undef SIMSERIAL_DEBUG  /* define this to get some debug information */
  41
  42 #define KEYBOARD_INTR   3       /* must match with simulator! */
  43
  44 #define NR_PORTS        1       /* only one port for now */
  45
  46 #define IRQ_T(info) ((info->flags & ASYNC_SHARE_IRQ) ? IRQF_SHARED : IRQF_DISABLED)
  47
  48 #define SSC_GETCHAR     21
  49
  50 extern long ia64_ssc (long, long, long, long, int);
  51 extern void ia64_ssc_connect_irq (long intr, long irq);
  52
  53 static char *serial_name = "SimSerial driver";
  54 static char *serial_version = "0.6";
  55
  56 /*
  57  * This has been extracted from asm/serial.h. We need one eventually but
  58  * I don't know exactly what we're going to put in it so just fake one
  59  * for now.
  60  */
  61 #define BASE_BAUD ( 1843200 / 16 )
  62
  63 #define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
  64
  65 /*
  66  * Most of the values here are meaningless to this particular driver.
  67  * However some values must be preserved for the code (leveraged from serial.c
  68  * to work correctly).
  69  * port must not be 0
  70  * type must not be UNKNOWN
  71  * So I picked arbitrary (guess from where?) values instead
  72  */
  73 static struct serial_state rs_table[NR_PORTS]={
  74   /* UART CLK   PORT IRQ     FLAGS        */
  75   { 0, BASE_BAUD, 0x3F8, 0, STD_COM_FLAGS,0,PORT_16550 }  /* ttyS0 */
  76 };
  77
  78 /*
  79  * Just for the fun of it !
  80  */
  81 static struct serial_uart_config uart_config[] = {
  82         { "unknown", 1, 0 },
  83         { "8250", 1, 0 },
  84         { "16450", 1, 0 },
  85         { "16550", 1, 0 },
  86         { "16550A", 16, UART_CLEAR_FIFO | UART_USE_FIFO },
  87         { "cirrus", 1, 0 },
  88         { "ST16650", 1, UART_CLEAR_FIFO | UART_STARTECH },
  89         { "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO |
  90                   UART_STARTECH },
  91         { "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO},
  92         { NULL, 0}
  93 };
  94
  95 struct tty_driver *hp_simserial_driver;
  96
  97 static struct async_struct *IRQ_ports[NR_IRQS];
  98
  99 static struct console *console;
 100
 101 static unsigned char *tmp_buf;
 102
 103 extern struct console *console_drivers; /* from kernel/printk.c */
 104
 105 /*
 106  * ------------------------------------------------------------
 107  * rs_stop() and rs_start()
 108  *
 109  * This routines are called before setting or resetting tty->stopped.
 110  * They enable or disable transmitter interrupts, as necessary.
 111  * ------------------------------------------------------------
 112  */
 113 static void rs_stop(struct tty_struct *tty)
 114 {
 115 #ifdef SIMSERIAL_DEBUG
 116         printk("rs_stop: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
 117                 tty->stopped, tty->hw_stopped, tty->flow_stopped);
 118 #endif
 119
 120 }
 121
 122 static void rs_start(struct tty_struct *tty)
 123 {
 124 #ifdef SIMSERIAL_DEBUG
 125         printk("rs_start: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
 126                 tty->stopped, tty->hw_stopped, tty->flow_stopped);
 127 #endif
 128 }
 129
 130 static  void receive_chars(struct tty_struct *tty)
 131 {
 132         unsigned char ch;
 133         static unsigned char seen_esc = 0;
 134
 135         while ( (ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR)) ) {
 136                 if ( ch == 27 && seen_esc == 0 ) {
 137                         seen_esc = 1;
 138                         continue;
 139                 } else {
 140                         if ( seen_esc==1 && ch == 'O' ) {
 141                                 seen_esc = 2;
 142                                 continue;
 143                         } else if ( seen_esc == 2 ) {
 144                                 if ( ch == 'P' ) /* F1 */
 145                                         show_state();
 146 #ifdef CONFIG_MAGIC_SYSRQ
 147                                 if ( ch == 'S' ) { /* F4 */
 148                                         do
 149                                                 ch = ia64_ssc(0, 0, 0, 0,
 150                                                               SSC_GETCHAR);
 151                                         while (!ch);
 152                                         handle_sysrq(ch);
 153                                 }
 154 #endif
 155                                 seen_esc = 0;
 156                                 continue;
 157                         }
 158                 }
 159                 seen_esc = 0;
 160
 161                 if (tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0)
 162                         break;
 163         }
 164         tty_flip_buffer_push(tty);
 165 }
 166
 167 /*
 168  * This is the serial driver's interrupt routine for a single port
 169  */
 170 static irqreturn_t rs_interrupt_single(int irq, void *dev_id)
 171 {
 172         struct async_struct * info;
 173
 174         /*
 175          * I don't know exactly why they don't use the dev_id opaque data
 176          * pointer instead of this extra lookup table
 177          */
 178         info = IRQ_ports[irq];
 179         if (!info || !info->tty) {
 180                 printk(KERN_INFO "simrs_interrupt_single: info|tty=0 info=%p problem\n", info);
 181                 return IRQ_NONE;
 182         }
 183         /*
 184          * pretty simple in our case, because we only get interrupts
 185          * on inbound traffic
 186          */
 187         receive_chars(info->tty);
 188         return IRQ_HANDLED;
 189 }
 190
 191 /*
 192  * -------------------------------------------------------------------
 193  * Here ends the serial interrupt routines.
 194  * -------------------------------------------------------------------
 195  */
 196
 197 static void do_softint(struct work_struct *private_)
 198 {
 199         printk(KERN_ERR "simserial: do_softint called\n");
 200 }
 201
 202 static int rs_put_char(struct tty_struct *tty, unsigned char ch)
 203 {
 204         struct async_struct *info = (struct async_struct *)tty->driver_data;
 205         unsigned long flags;
 206
 207         if (!tty || !info->xmit.buf)
 208                 return 0;
 209
 210         local_irq_save(flags);
 211         if (CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) == 0) {
 212                 local_irq_restore(flags);
 213                 return 0;
 214         }
 215         info->xmit.buf[info->xmit.head] = ch;
 216         info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
 217         local_irq_restore(flags);
 218         return 1;
 219 }
 220
 221 static void transmit_chars(struct async_struct *info, int *intr_done)
 222 {
 223         int count;
 224         unsigned long flags;
 225
 226
 227         local_irq_save(flags);
 228
 229         if (info->x_char) {
 230                 char c = info->x_char;
 231
 232                 console->write(console, &c, 1);
 233
 234                 info->state->icount.tx++;
 235                 info->x_char = 0;
 236
 237                 goto out;
 238         }
 239
 240         if (info->xmit.head == info->xmit.tail || info->tty->stopped || info->tty->hw_stopped) {
 241 #ifdef SIMSERIAL_DEBUG
 242                 printk("transmit_chars: head=%d, tail=%d, stopped=%d\n",
 243                        info->xmit.head, info->xmit.tail, info->tty->stopped);
 244 #endif
 245                 goto out;
 246         }
 247         /*
 248          * We removed the loop and try to do it in to chunks. We need
 249          * 2 operations maximum because it's a ring buffer.
 250          *
 251          * First from current to tail if possible.
 252          * Then from the beginning of the buffer until necessary
 253          */
 254
 255         count = min(CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE),
 256                     SERIAL_XMIT_SIZE - info->xmit.tail);
 257         console->write(console, info->xmit.buf+info->xmit.tail, count);
 258
 259         info->xmit.tail = (info->xmit.tail+count) & (SERIAL_XMIT_SIZE-1);
 260
 261         /*
 262          * We have more at the beginning of the buffer
 263          */
 264         count = CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 265         if (count) {
 266                 console->write(console, info->xmit.buf, count);
 267                 info->xmit.tail += count;
 268         }
 269 out:
 270         local_irq_restore(flags);
 271 }
 272
 273 static void rs_flush_chars(struct tty_struct *tty)
 274 {
 275         struct async_struct *info = (struct async_struct *)tty->driver_data;
 276
 277         if (info->xmit.head == info->xmit.tail || tty->stopped || tty->hw_stopped ||
 278             !info->xmit.buf)
 279                 return;
 280
 281         transmit_chars(info, NULL);
 282 }
 283
 284
 285 static int rs_write(struct tty_struct * tty,
 286                     const unsigned char *buf, int count)
 287 {
 288         int     c, ret = 0;
 289         struct async_struct *info = (struct async_struct *)tty->driver_data;
 290         unsigned long flags;
 291
 292         if (!tty || !info->xmit.buf || !tmp_buf) return 0;
 293
 294         local_irq_save(flags);
 295         while (1) {
 296                 c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 297                 if (count < c)
 298                         c = count;
 299                 if (c <= 0) {
 300                         break;
 301                 }
 302                 memcpy(info->xmit.buf + info->xmit.head, buf, c);
 303                 info->xmit.head = ((info->xmit.head + c) &
 304                                    (SERIAL_XMIT_SIZE-1));
 305                 buf += c;
 306                 count -= c;
 307                 ret += c;
 308         }
 309         local_irq_restore(flags);
 310         /*
 311          * Hey, we transmit directly from here in our case
 312          */
 313         if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE)
 314             && !tty->stopped && !tty->hw_stopped) {
 315                 transmit_chars(info, NULL);
 316         }
 317         return ret;
 318 }
 319
 320 static int rs_write_room(struct tty_struct *tty)
 321 {
 322         struct async_struct *info = (struct async_struct *)tty->driver_data;
 323
 324         return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 325 }
 326
 327 static int rs_chars_in_buffer(struct tty_struct *tty)
 328 {
 329         struct async_struct *info = (struct async_struct *)tty->driver_data;
 330
 331         return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 332 }
 333
 334 static void rs_flush_buffer(struct tty_struct *tty)
 335 {
 336         struct async_struct *info = (struct async_struct *)tty->driver_data;
 337         unsigned long flags;
 338
 339         local_irq_save(flags);
 340         info->xmit.head = info->xmit.tail = 0;
 341         local_irq_restore(flags);
 342
 343         tty_wakeup(tty);
 344 }
 345
 346 /*
 347  * This function is used to send a high-priority XON/XOFF character to
 348  * the device
 349  */
 350 static void rs_send_xchar(struct tty_struct *tty, char ch)
 351 {
 352         struct async_struct *info = (struct async_struct *)tty->driver_data;
 353
 354         info->x_char = ch;
 355         if (ch) {
 356                 /*
 357                  * I guess we could call console->write() directly but
 358                  * let's do that for now.
 359                  */
 360                 transmit_chars(info, NULL);
 361         }
 362 }
 363
 364 /*
 365  * ------------------------------------------------------------
 366  * rs_throttle()
 367  *
 368  * This routine is called by the upper-layer tty layer to signal that
 369  * incoming characters should be throttled.
 370  * ------------------------------------------------------------
 371  */
 372 static void rs_throttle(struct tty_struct * tty)
 373 {
 374         if (I_IXOFF(tty)) rs_send_xchar(tty, STOP_CHAR(tty));
 375
 376         printk(KERN_INFO "simrs_throttle called\n");
 377 }
 378
 379 static void rs_unthrottle(struct tty_struct * tty)
 380 {
 381         struct async_struct *info = (struct async_struct *)tty->driver_data;
 382
 383         if (I_IXOFF(tty)) {
 384                 if (info->x_char)
 385                         info->x_char = 0;
 386                 else
 387                         rs_send_xchar(tty, START_CHAR(tty));
 388         }
 389         printk(KERN_INFO "simrs_unthrottle called\n");
 390 }
 391
 392
 393 static int rs_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
 394 {
 395         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
 396             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
 397             (cmd != TIOCMIWAIT)) {
 398                 if (tty->flags & (1 << TTY_IO_ERROR))
 399                     return -EIO;
 400         }
 401
 402         switch (cmd) {
 403                 case TIOCGSERIAL:
 404                         printk(KERN_INFO "simrs_ioctl TIOCGSERIAL called\n");
 405                         return 0;
 406                 case TIOCSSERIAL:
 407                         printk(KERN_INFO "simrs_ioctl TIOCSSERIAL called\n");
 408                         return 0;
 409                 case TIOCSERCONFIG:
 410                         printk(KERN_INFO "rs_ioctl: TIOCSERCONFIG called\n");
 411                         return -EINVAL;
 412
 413                 case TIOCSERGETLSR: /* Get line status register */
 414                         printk(KERN_INFO "rs_ioctl: TIOCSERGETLSR called\n");
 415                         return  -EINVAL;
 416
 417                 case TIOCSERGSTRUCT:
 418                         printk(KERN_INFO "rs_ioctl: TIOCSERGSTRUCT called\n");
 419 #if 0
 420                         if (copy_to_user((struct async_struct *) arg,
 421                                          info, sizeof(struct async_struct)))
 422                                 return -EFAULT;
 423 #endif
 424                         return 0;
 425
 426                 /*
 427                  * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
 428                  * - mask passed in arg for lines of interest
 429                  *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
 430                  * Caller should use TIOCGICOUNT to see which one it was
 431                  */
 432                 case TIOCMIWAIT:
 433                         printk(KERN_INFO "rs_ioctl: TIOCMIWAIT: called\n");
 434                         return 0;
 435                 case TIOCSERGWILD:
 436                 case TIOCSERSWILD:
 437                         /* "setserial -W" is called in Debian boot */
 438                         printk (KERN_INFO "TIOCSER?WILD ioctl obsolete, ignored.\n");
 439                         return 0;
 440
 441                 default:
 442                         return -ENOIOCTLCMD;
 443                 }
 444         return 0;
 445 }
 446
 447 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 448
 449 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
 450 {
 451         /* Handle turning off CRTSCTS */
 452         if ((old_termios->c_cflag & CRTSCTS) &&
 453             !(tty->termios->c_cflag & CRTSCTS)) {
 454                 tty->hw_stopped = 0;
 455                 rs_start(tty);
 456         }
 457 }
 458 /*
 459  * This routine will shutdown a serial port; interrupts are disabled, and
 460  * DTR is dropped if the hangup on close termio flag is on.
 461  */
 462 static void shutdown(struct async_struct * info)
 463 {
 464         unsigned long   flags;
 465         struct serial_state *state;
 466         int             retval;
 467
 468         if (!(info->flags & ASYNC_INITIALIZED)) return;
 469
 470         state = info->state;
 471
 472 #ifdef SIMSERIAL_DEBUG
 473         printk("Shutting down serial port %d (irq %d)....", info->line,
 474                state->irq);
 475 #endif
 476
 477         local_irq_save(flags);
 478         {
 479                 /*
 480                  * First unlink the serial port from the IRQ chain...
 481                  */
 482                 if (info->next_port)
 483                         info->next_port->prev_port = info->prev_port;
 484                 if (info->prev_port)
 485                         info->prev_port->next_port = info->next_port;
 486                 else
 487                         IRQ_ports[state->irq] = info->next_port;
 488
 489                 /*
 490                  * Free the IRQ, if necessary
 491                  */
 492                 if (state->irq && (!IRQ_ports[state->irq] ||
 493                                    !IRQ_ports[state->irq]->next_port)) {
 494                         if (IRQ_ports[state->irq]) {
 495                                 free_irq(state->irq, NULL);
 496                                 retval = request_irq(state->irq, rs_interrupt_single,
 497                                                      IRQ_T(info), "serial", NULL);
 498
 499                                 if (retval)
 500                                         printk(KERN_ERR "serial shutdown: request_irq: error %d"
 501                                                "  Couldn't reacquire IRQ.\n", retval);
 502                         } else
 503                                 free_irq(state->irq, NULL);
 504                 }
 505
 506                 if (info->xmit.buf) {
 507                         free_page((unsigned long) info->xmit.buf);
 508                         info->xmit.buf = NULL;
 509                 }
 510
 511                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
 512
 513                 info->flags &= ~ASYNC_INITIALIZED;
 514         }
 515         local_irq_restore(flags);
 516 }
 517
 518 /*
 519  * ------------------------------------------------------------
 520  * rs_close()
 521  *
 522  * This routine is called when the serial port gets closed.  First, we
 523  * wait for the last remaining data to be sent.  Then, we unlink its
 524  * async structure from the interrupt chain if necessary, and we free
 525  * that IRQ if nothing is left in the chain.
 526  * ------------------------------------------------------------
 527  */
 528 static void rs_close(struct tty_struct *tty, struct file * filp)
 529 {
 530         struct async_struct * info = (struct async_struct *)tty->driver_data;
 531         struct serial_state *state;
 532         unsigned long flags;
 533
 534         if (!info ) return;
 535
 536         state = info->state;
 537
 538         local_irq_save(flags);
 539         if (tty_hung_up_p(filp)) {
 540 #ifdef SIMSERIAL_DEBUG
 541                 printk("rs_close: hung_up\n");
 542 #endif
 543                 local_irq_restore(flags);
 544                 return;
 545         }
 546 #ifdef SIMSERIAL_DEBUG
 547         printk("rs_close ttys%d, count = %d\n", info->line, state->count);
 548 #endif
 549         if ((tty->count == 1) && (state->count != 1)) {
 550                 /*
 551                  * Uh, oh.  tty->count is 1, which means that the tty
 552                  * structure will be freed.  state->count should always
 553                  * be one in these conditions.  If it's greater than
 554                  * one, we've got real problems, since it means the
 555                  * serial port won't be shutdown.
 556                  */
 557                 printk(KERN_ERR "rs_close: bad serial port count; tty->count is 1, "
 558                        "state->count is %d\n", state->count);
 559                 state->count = 1;
 560         }
 561         if (--state->count < 0) {
 562                 printk(KERN_ERR "rs_close: bad serial port count for ttys%d: %d\n",
 563                        info->line, state->count);
 564                 state->count = 0;
 565         }
 566         if (state->count) {
 567                 local_irq_restore(flags);
 568                 return;
 569         }
 570         info->flags |= ASYNC_CLOSING;
 571         local_irq_restore(flags);
 572
 573         /*
 574          * Now we wait for the transmit buffer to clear; and we notify
 575          * the line discipline to only process XON/XOFF characters.
 576          */
 577         shutdown(info);
 578         rs_flush_buffer(tty);
 579         tty_ldisc_flush(tty);
 580         info->event = 0;
 581         info->tty = NULL;
 582         if (info->blocked_open) {
 583                 if (info->close_delay)
 584                         schedule_timeout_interruptible(info->close_delay);
 585                 wake_up_interruptible(&info->open_wait);
 586         }
 587         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
 588         wake_up_interruptible(&info->close_wait);
 589 }
 590
 591 /*
 592  * rs_wait_until_sent() --- wait until the transmitter is empty
 593  */
 594 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
 595 {
 596 }
 597
 598
 599 /*
 600  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 601  */
 602 static void rs_hangup(struct tty_struct *tty)
 603 {
 604         struct async_struct * info = (struct async_struct *)tty->driver_data;
 605         struct serial_state *state = info->state;
 606
 607 #ifdef SIMSERIAL_DEBUG
 608         printk("rs_hangup: called\n");
 609 #endif
 610
 611         state = info->state;
 612
 613         rs_flush_buffer(tty);
 614         if (info->flags & ASYNC_CLOSING)
 615                 return;
 616         shutdown(info);
 617
 618         info->event = 0;
 619         state->count = 0;
 620         info->flags &= ~ASYNC_NORMAL_ACTIVE;
 621         info->tty = NULL;
 622         wake_up_interruptible(&info->open_wait);
 623 }
 624
 625
 626 static int get_async_struct(int line, struct async_struct **ret_info)
 627 {
 628         struct async_struct *info;
 629         struct serial_state *sstate;
 630
 631         sstate = rs_table + line;
 632         sstate->count++;
 633         if (sstate->info) {
 634                 *ret_info = sstate->info;
 635                 return 0;
 636         }
 637         info = kzalloc(sizeof(struct async_struct), GFP_KERNEL);
 638         if (!info) {
 639                 sstate->count--;
 640                 return -ENOMEM;
 641         }
 642         init_waitqueue_head(&info->open_wait);
 643         init_waitqueue_head(&info->close_wait);
 644         init_waitqueue_head(&info->delta_msr_wait);
 645         info->magic = SERIAL_MAGIC;
 646         info->port = sstate->port;
 647         info->flags = sstate->flags;
 648         info->xmit_fifo_size = sstate->xmit_fifo_size;
 649         info->line = line;
 650         INIT_WORK(&info->work, do_softint);
 651         info->state = sstate;
 652         if (sstate->info) {
 653                 kfree(info);
 654                 *ret_info = sstate->info;
 655                 return 0;
 656         }
 657         *ret_info = sstate->info = info;
 658         return 0;
 659 }
 660
 661 static int
 662 startup(struct async_struct *info)
 663 {
 664         unsigned long flags;
 665         int     retval=0;
 666         irq_handler_t handler;
 667         struct serial_state *state= info->state;
 668         unsigned long page;
 669
 670         page = get_zeroed_page(GFP_KERNEL);
 671         if (!page)
 672                 return -ENOMEM;
 673
 674         local_irq_save(flags);
 675
 676         if (info->flags & ASYNC_INITIALIZED) {
 677                 free_page(page);
 678                 goto errout;
 679         }
 680
 681         if (!state->port || !state->type) {
 682                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
 683                 free_page(page);
 684                 goto errout;
 685         }
 686         if (info->xmit.buf)
 687                 free_page(page);
 688         else
 689                 info->xmit.buf = (unsigned char *) page;
 690
 691 #ifdef SIMSERIAL_DEBUG
 692         printk("startup: ttys%d (irq %d)...", info->line, state->irq);
 693 #endif
 694
 695         /*
 696          * Allocate the IRQ if necessary
 697          */
 698         if (state->irq && (!IRQ_ports[state->irq] ||
 699                           !IRQ_ports[state->irq]->next_port)) {
 700                 if (IRQ_ports[state->irq]) {
 701                         retval = -EBUSY;
 702                         goto errout;
 703                 } else
 704                         handler = rs_interrupt_single;
 705
 706                 retval = request_irq(state->irq, handler, IRQ_T(info), "simserial", NULL);
 707                 if (retval) {
 708                         if (capable(CAP_SYS_ADMIN)) {
 709                                 if (info->tty)
 710                                         set_bit(TTY_IO_ERROR,
 711                                                 &info->tty->flags);
 712                                 retval = 0;
 713                         }
 714                         goto errout;
 715                 }
 716         }
 717
 718         /*
 719          * Insert serial port into IRQ chain.
 720          */
 721         info->prev_port = NULL;
 722         info->next_port = IRQ_ports[state->irq];
 723         if (info->next_port)
 724                 info->next_port->prev_port = info;
 725         IRQ_ports[state->irq] = info;
 726
 727         if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags);
 728
 729         info->xmit.head = info->xmit.tail = 0;
 730
 731 #if 0
 732         /*
 733          * Set up serial timers...
 734          */
 735         timer_table[RS_TIMER].expires = jiffies + 2*HZ/100;
 736         timer_active |= 1 << RS_TIMER;
 737 #endif
 738
 739         /*
 740          * Set up the tty->alt_speed kludge
 741          */
 742         if (info->tty) {
 743                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
 744                         info->tty->alt_speed = 57600;
 745                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
 746                         info->tty->alt_speed = 115200;
 747                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
 748                         info->tty->alt_speed = 230400;
 749                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
 750                         info->tty->alt_speed = 460800;
 751         }
 752
 753         info->flags |= ASYNC_INITIALIZED;
 754         local_irq_restore(flags);
 755         return 0;
 756
 757 errout:
 758         local_irq_restore(flags);
 759         return retval;
 760 }
 761
 762
 763 /*
 764  * This routine is called whenever a serial port is opened.  It
 765  * enables interrupts for a serial port, linking in its async structure into
 766  * the IRQ chain.   It also performs the serial-specific
 767  * initialization for the tty structure.
 768  */
 769 static int rs_open(struct tty_struct *tty, struct file * filp)
 770 {
 771         struct async_struct     *info;
 772         int                     retval, line;
 773         unsigned long           page;
 774
 775         line = tty->index;
 776         if ((line < 0) || (line >= NR_PORTS))
 777                 return -ENODEV;
 778         retval = get_async_struct(line, &info);
 779         if (retval)
 780                 return retval;
 781         tty->driver_data = info;
 782         info->tty = tty;
 783
 784 #ifdef SIMSERIAL_DEBUG
 785         printk("rs_open %s, count = %d\n", tty->name, info->state->count);
 786 #endif
 787         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 788
 789         if (!tmp_buf) {
 790                 page = get_zeroed_page(GFP_KERNEL);
 791                 if (!page)
 792                         return -ENOMEM;
 793                 if (tmp_buf)
 794                         free_page(page);
 795                 else
 796                         tmp_buf = (unsigned char *) page;
 797         }
 798
 799         /*
 800          * If the port is the middle of closing, bail out now
 801          */
 802         if (tty_hung_up_p(filp) ||
 803             (info->flags & ASYNC_CLOSING)) {
 804                 if (info->flags & ASYNC_CLOSING)
 805                         interruptible_sleep_on(&info->close_wait);
 806 #ifdef SERIAL_DO_RESTART
 807                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
 808                         -EAGAIN : -ERESTARTSYS);
 809 #else
 810                 return -EAGAIN;
 811 #endif
 812         }
 813
 814         /*
 815          * Start up serial port
 816          */
 817         retval = startup(info);
 818         if (retval) {
 819                 return retval;
 820         }
 821
 822         /*
 823          * figure out which console to use (should be one already)
 824          */
 825         console = console_drivers;
 826         while (console) {
 827                 if ((console->flags & CON_ENABLED) && console->write) break;
 828                 console = console->next;
 829         }
 830
 831 #ifdef SIMSERIAL_DEBUG
 832         printk("rs_open ttys%d successful\n", info->line);
 833 #endif
 834         return 0;
 835 }
 836
 837 /*
 838  * /proc fs routines....
 839  */
 840
 841 static inline void line_info(struct seq_file *m, struct serial_state *state)
 842 {
 843         seq_printf(m, "%d: uart:%s port:%lX irq:%d\n",
 844                        state->line, uart_config[state->type].name,
 845                        state->port, state->irq);
 846 }
 847
 848 static int rs_proc_show(struct seq_file *m, void *v)
 849 {
 850         int i;
 851
 852         seq_printf(m, "simserinfo:1.0 driver:%s\n", serial_version);
 853         for (i = 0; i < NR_PORTS; i++)
 854                 line_info(m, &rs_table[i]);
 855         return 0;
 856 }
 857
 858 static int rs_proc_open(struct inode *inode, struct file *file)
 859 {
 860         return single_open(file, rs_proc_show, NULL);
 861 }
 862
 863 static const struct file_operations rs_proc_fops = {
 864         .owner          = THIS_MODULE,
 865         .open           = rs_proc_open,
 866         .read           = seq_read,
 867         .llseek         = seq_lseek,
 868         .release        = single_release,
 869 };
 870
 871 /*
 872  * ---------------------------------------------------------------------
 873  * rs_init() and friends
 874  *
 875  * rs_init() is called at boot-time to initialize the serial driver.
 876  * ---------------------------------------------------------------------
 877  */
 878
 879 /*
 880  * This routine prints out the appropriate serial driver version
 881  * number, and identifies which options were configured into this
 882  * driver.
 883  */
 884 static inline void show_serial_version(void)
 885 {
 886         printk(KERN_INFO "%s version %s with", serial_name, serial_version);
 887         printk(KERN_INFO " no serial options enabled\n");
 888 }
 889
 890 static const struct tty_operations hp_ops = {
 891         .open = rs_open,
 892         .close = rs_close,
 893         .write = rs_write,
 894         .put_char = rs_put_char,
 895         .flush_chars = rs_flush_chars,
 896         .write_room = rs_write_room,
 897         .chars_in_buffer = rs_chars_in_buffer,
 898         .flush_buffer = rs_flush_buffer,
 899         .ioctl = rs_ioctl,
 900         .throttle = rs_throttle,
 901         .unthrottle = rs_unthrottle,
 902         .send_xchar = rs_send_xchar,
 903         .set_termios = rs_set_termios,
 904         .stop = rs_stop,
 905         .start = rs_start,
 906         .hangup = rs_hangup,
 907         .wait_until_sent = rs_wait_until_sent,
 908         .proc_fops = &rs_proc_fops,
 909 };
 910
 911 /*
 912  * The serial driver boot-time initialization code!
 913  */
 914 static int __init
 915 simrs_init (void)
 916 {
 917         int                     i, rc;
 918         struct serial_state     *state;
 919
 920         if (!ia64_platform_is("hpsim"))
 921                 return -ENODEV;
 922
 923         hp_simserial_driver = alloc_tty_driver(1);
 924         if (!hp_simserial_driver)
 925                 return -ENOMEM;
 926
 927         show_serial_version();
 928
 929         /* Initialize the tty_driver structure */
 930
 931         hp_simserial_driver->owner = THIS_MODULE;
 932         hp_simserial_driver->driver_name = "simserial";
 933         hp_simserial_driver->name = "ttyS";
 934         hp_simserial_driver->major = TTY_MAJOR;
 935         hp_simserial_driver->minor_start = 64;
 936         hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
 937         hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
 938         hp_simserial_driver->init_termios = tty_std_termios;
 939         hp_simserial_driver->init_termios.c_cflag =
 940                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 941         hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
 942         tty_set_operations(hp_simserial_driver, &hp_ops);
 943
 944         /*
 945          * Let's have a little bit of fun !
 946          */
 947         for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
 948
 949                 if (state->type == PORT_UNKNOWN) continue;
 950
 951                 if (!state->irq) {
 952                         if ((rc = assign_irq_vector(AUTO_ASSIGN)) < 0)
 953                                 panic("%s: out of interrupt vectors!\n",
 954                                       __func__);
 955                         state->irq = rc;
 956                         ia64_ssc_connect_irq(KEYBOARD_INTR, state->irq);
 957                 }
 958
 959                 printk(KERN_INFO "ttyS%d at 0x%04lx (irq = %d) is a %s\n",
 960                        state->line,
 961                        state->port, state->irq,
 962                        uart_config[state->type].name);
 963         }
 964
 965         if (tty_register_driver(hp_simserial_driver))
 966                 panic("Couldn't register simserial driver\n");
 967
 968         return 0;
 969 }
 970
 971 #ifndef MODULE
 972 __initcall(simrs_init);
 973 #endif