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/config.h>
  20 #include <linux/init.h>
  21 #include <linux/errno.h>
  22 #include <linux/sched.h>
  23 #include <linux/tty.h>
  24 #include <linux/tty_flip.h>
  25 #include <linux/major.h>
  26 #include <linux/fcntl.h>
  27 #include <linux/mm.h>
  28 #include <linux/slab.h>
  29 #include <linux/console.h>
  30 #include <linux/module.h>
  31 #include <linux/serial.h>
  32 #include <linux/serialP.h>
  33
  34 #include <asm/irq.h>
  35 #include <asm/hw_irq.h>
  36 #include <asm/uaccess.h>
  37
  38 #ifdef CONFIG_KDB
  39 # include <linux/kdb.h>
  40 #endif
  41
  42 #undef SIMSERIAL_DEBUG  /* define this to get some debug information */
  43
  44 #define KEYBOARD_INTR   3       /* must match with simulator! */
  45
  46 #define NR_PORTS        1       /* only one port for now */
  47 #define SERIAL_INLINE   1
  48
  49 #ifdef SERIAL_INLINE
  50 #define _INLINE_ inline
  51 #endif
  52
  53 #define IRQ_T(info) ((info->flags & ASYNC_SHARE_IRQ) ? SA_SHIRQ : SA_INTERRUPT)
  54
  55 #define SSC_GETCHAR     21
  56
  57 extern long ia64_ssc (long, long, long, long, int);
  58 extern void ia64_ssc_connect_irq (long intr, long irq);
  59
  60 static char *serial_name = "SimSerial driver";
  61 static char *serial_version = "0.6";
  62
  63 /*
  64  * This has been extracted from asm/serial.h. We need one eventually but
  65  * I don't know exactly what we're going to put in it so just fake one
  66  * for now.
  67  */
  68 #define BASE_BAUD ( 1843200 / 16 )
  69
  70 #define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
  71
  72 /*
  73  * Most of the values here are meaningless to this particular driver.
  74  * However some values must be preserved for the code (leveraged from serial.c
  75  * to work correctly).
  76  * port must not be 0
  77  * type must not be UNKNOWN
  78  * So I picked arbitrary (guess from where?) values instead
  79  */
  80 static struct serial_state rs_table[NR_PORTS]={
  81   /* UART CLK   PORT IRQ     FLAGS        */
  82   { 0, BASE_BAUD, 0x3F8, 0, STD_COM_FLAGS,0,PORT_16550 }  /* ttyS0 */
  83 };
  84
  85 /*
  86  * Just for the fun of it !
  87  */
  88 static struct serial_uart_config uart_config[] = {
  89         { "unknown", 1, 0 },
  90         { "8250", 1, 0 },
  91         { "16450", 1, 0 },
  92         { "16550", 1, 0 },
  93         { "16550A", 16, UART_CLEAR_FIFO | UART_USE_FIFO },
  94         { "cirrus", 1, 0 },
  95         { "ST16650", 1, UART_CLEAR_FIFO | UART_STARTECH },
  96         { "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO |
  97                   UART_STARTECH },
  98         { "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO},
  99         { 0, 0}
 100 };
 101
 102 struct tty_driver *hp_simserial_driver;
 103
 104 static struct async_struct *IRQ_ports[NR_IRQS];
 105
 106 static struct console *console;
 107
 108 static unsigned char *tmp_buf;
 109 static DECLARE_MUTEX(tmp_buf_sem);
 110
 111 extern struct console *console_drivers; /* from kernel/printk.c */
 112
 113 /*
 114  * ------------------------------------------------------------
 115  * rs_stop() and rs_start()
 116  *
 117  * This routines are called before setting or resetting tty->stopped.
 118  * They enable or disable transmitter interrupts, as necessary.
 119  * ------------------------------------------------------------
 120  */
 121 static void rs_stop(struct tty_struct *tty)
 122 {
 123 #ifdef SIMSERIAL_DEBUG
 124         printk("rs_stop: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
 125                 tty->stopped, tty->hw_stopped, tty->flow_stopped);
 126 #endif
 127
 128 }
 129
 130 static void rs_start(struct tty_struct *tty)
 131 {
 132 #if SIMSERIAL_DEBUG
 133         printk("rs_start: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
 134                 tty->stopped, tty->hw_stopped, tty->flow_stopped);
 135 #endif
 136 }
 137
 138 static  void receive_chars(struct tty_struct *tty, struct pt_regs *regs)
 139 {
 140         unsigned char ch;
 141         static unsigned char seen_esc = 0;
 142
 143         while ( (ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR)) ) {
 144                 if ( ch == 27 && seen_esc == 0 ) {
 145                         seen_esc = 1;
 146                         continue;
 147                 } else {
 148                         if ( seen_esc==1 && ch == 'O' ) {
 149                                 seen_esc = 2;
 150                                 continue;
 151                         } else if ( seen_esc == 2 ) {
 152                                 if ( ch == 'P' ) show_state();          /* F1 key */
 153 #ifdef CONFIG_KDB
 154                                 if ( ch == 'S' )
 155                                         kdb(KDB_REASON_KEYBOARD, 0, (kdb_eframe_t) regs);
 156 #endif
 157
 158                                 seen_esc = 0;
 159                                 continue;
 160                         }
 161                 }
 162                 seen_esc = 0;
 163                 if (tty->flip.count >= TTY_FLIPBUF_SIZE) break;
 164
 165                 *tty->flip.char_buf_ptr = ch;
 166
 167                 *tty->flip.flag_buf_ptr = 0;
 168
 169                 tty->flip.flag_buf_ptr++;
 170                 tty->flip.char_buf_ptr++;
 171                 tty->flip.count++;
 172         }
 173         tty_flip_buffer_push(tty);
 174 }
 175
 176 /*
 177  * This is the serial driver's interrupt routine for a single port
 178  */
 179 static irqreturn_t rs_interrupt_single(int irq, void *dev_id, struct pt_regs * regs)
 180 {
 181         struct async_struct * info;
 182
 183         /*
 184          * I don't know exactly why they don't use the dev_id opaque data
 185          * pointer instead of this extra lookup table
 186          */
 187         info = IRQ_ports[irq];
 188         if (!info || !info->tty) {
 189                 printk(KERN_INFO "simrs_interrupt_single: info|tty=0 info=%p problem\n", info);
 190                 return IRQ_NONE;
 191         }
 192         /*
 193          * pretty simple in our case, because we only get interrupts
 194          * on inbound traffic
 195          */
 196         receive_chars(info->tty, regs);
 197         return IRQ_HANDLED;
 198 }
 199
 200 /*
 201  * -------------------------------------------------------------------
 202  * Here ends the serial interrupt routines.
 203  * -------------------------------------------------------------------
 204  */
 205
 206 #if 0
 207 /*
 208  * not really used in our situation so keep them commented out for now
 209  */
 210 static DECLARE_TASK_QUEUE(tq_serial); /* used to be at the top of the file */
 211 static void do_serial_bh(void)
 212 {
 213         run_task_queue(&tq_serial);
 214         printk(KERN_ERR "do_serial_bh: called\n");
 215 }
 216 #endif
 217
 218 static void do_softint(void *private_)
 219 {
 220         printk(KERN_ERR "simserial: do_softint called\n");
 221 }
 222
 223 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
 224 {
 225         struct async_struct *info = (struct async_struct *)tty->driver_data;
 226         unsigned long flags;
 227
 228         if (!tty || !info->xmit.buf) return;
 229
 230         local_irq_save(flags);
 231         if (CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) == 0) {
 232                 local_irq_restore(flags);
 233                 return;
 234         }
 235         info->xmit.buf[info->xmit.head] = ch;
 236         info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
 237         local_irq_restore(flags);
 238 }
 239
 240 static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done)
 241 {
 242         int count;
 243         unsigned long flags;
 244
 245
 246         local_irq_save(flags);
 247
 248         if (info->x_char) {
 249                 char c = info->x_char;
 250
 251                 console->write(console, &c, 1);
 252
 253                 info->state->icount.tx++;
 254                 info->x_char = 0;
 255
 256                 goto out;
 257         }
 258
 259         if (info->xmit.head == info->xmit.tail || info->tty->stopped || info->tty->hw_stopped) {
 260 #ifdef SIMSERIAL_DEBUG
 261                 printk("transmit_chars: head=%d, tail=%d, stopped=%d\n",
 262                        info->xmit.head, info->xmit.tail, info->tty->stopped);
 263 #endif
 264                 goto out;
 265         }
 266         /*
 267          * We removed the loop and try to do it in to chunks. We need
 268          * 2 operations maximum because it's a ring buffer.
 269          *
 270          * First from current to tail if possible.
 271          * Then from the beginning of the buffer until necessary
 272          */
 273
 274         count = min(CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE),
 275                     SERIAL_XMIT_SIZE - info->xmit.tail);
 276         console->write(console, info->xmit.buf+info->xmit.tail, count);
 277
 278         info->xmit.tail = (info->xmit.tail+count) & (SERIAL_XMIT_SIZE-1);
 279
 280         /*
 281          * We have more at the beginning of the buffer
 282          */
 283         count = CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 284         if (count) {
 285                 console->write(console, info->xmit.buf, count);
 286                 info->xmit.tail += count;
 287         }
 288 out:
 289         local_irq_restore(flags);
 290 }
 291
 292 static void rs_flush_chars(struct tty_struct *tty)
 293 {
 294         struct async_struct *info = (struct async_struct *)tty->driver_data;
 295
 296         if (info->xmit.head == info->xmit.tail || tty->stopped || tty->hw_stopped ||
 297             !info->xmit.buf)
 298                 return;
 299
 300         transmit_chars(info, NULL);
 301 }
 302
 303
 304 static int rs_write(struct tty_struct * tty, int from_user,
 305                     const unsigned char *buf, int count)
 306 {
 307         int     c, ret = 0;
 308         struct async_struct *info = (struct async_struct *)tty->driver_data;
 309         unsigned long flags;
 310
 311         if (!tty || !info->xmit.buf || !tmp_buf) return 0;
 312
 313         if (from_user) {
 314                 down(&tmp_buf_sem);
 315                 while (1) {
 316                         int c1;
 317                         c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 318                         if (count < c)
 319                                 c = count;
 320                         if (c <= 0)
 321                                 break;
 322
 323                         c -= copy_from_user(tmp_buf, buf, c);
 324                         if (!c) {
 325                                 if (!ret)
 326                                         ret = -EFAULT;
 327                                 break;
 328                         }
 329
 330                         local_irq_save(flags);
 331                         {
 332                                 c1 = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail,
 333                                                        SERIAL_XMIT_SIZE);
 334                                 if (c1 < c)
 335                                         c = c1;
 336                                 memcpy(info->xmit.buf + info->xmit.head, tmp_buf, c);
 337                                 info->xmit.head = ((info->xmit.head + c) &
 338                                                    (SERIAL_XMIT_SIZE-1));
 339                         }
 340                         local_irq_restore(flags);
 341
 342                         buf += c;
 343                         count -= c;
 344                         ret += c;
 345                 }
 346                 up(&tmp_buf_sem);
 347         } else {
 348                 local_irq_save(flags);
 349                 while (1) {
 350                         c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 351                         if (count < c)
 352                                 c = count;
 353                         if (c <= 0) {
 354                                 break;
 355                         }
 356                         memcpy(info->xmit.buf + info->xmit.head, buf, c);
 357                         info->xmit.head = ((info->xmit.head + c) &
 358                                            (SERIAL_XMIT_SIZE-1));
 359                         buf += c;
 360                         count -= c;
 361                         ret += c;
 362                 }
 363                 local_irq_restore(flags);
 364         }
 365         /*
 366          * Hey, we transmit directly from here in our case
 367          */
 368         if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE)
 369             && !tty->stopped && !tty->hw_stopped) {
 370                 transmit_chars(info, NULL);
 371         }
 372         return ret;
 373 }
 374
 375 static int rs_write_room(struct tty_struct *tty)
 376 {
 377         struct async_struct *info = (struct async_struct *)tty->driver_data;
 378
 379         return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 380 }
 381
 382 static int rs_chars_in_buffer(struct tty_struct *tty)
 383 {
 384         struct async_struct *info = (struct async_struct *)tty->driver_data;
 385
 386         return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 387 }
 388
 389 static void rs_flush_buffer(struct tty_struct *tty)
 390 {
 391         struct async_struct *info = (struct async_struct *)tty->driver_data;
 392         unsigned long flags;
 393
 394         local_irq_save(flags);
 395         info->xmit.head = info->xmit.tail = 0;
 396         local_irq_restore(flags);
 397
 398         wake_up_interruptible(&tty->write_wait);
 399
 400         if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
 401             tty->ldisc.write_wakeup)
 402                 (tty->ldisc.write_wakeup)(tty);
 403 }
 404
 405 /*
 406  * This function is used to send a high-priority XON/XOFF character to
 407  * the device
 408  */
 409 static void rs_send_xchar(struct tty_struct *tty, char ch)
 410 {
 411         struct async_struct *info = (struct async_struct *)tty->driver_data;
 412
 413         info->x_char = ch;
 414         if (ch) {
 415                 /*
 416                  * I guess we could call console->write() directly but
 417                  * let's do that for now.
 418                  */
 419                 transmit_chars(info, NULL);
 420         }
 421 }
 422
 423 /*
 424  * ------------------------------------------------------------
 425  * rs_throttle()
 426  *
 427  * This routine is called by the upper-layer tty layer to signal that
 428  * incoming characters should be throttled.
 429  * ------------------------------------------------------------
 430  */
 431 static void rs_throttle(struct tty_struct * tty)
 432 {
 433         if (I_IXOFF(tty)) rs_send_xchar(tty, STOP_CHAR(tty));
 434
 435         printk(KERN_INFO "simrs_throttle called\n");
 436 }
 437
 438 static void rs_unthrottle(struct tty_struct * tty)
 439 {
 440         struct async_struct *info = (struct async_struct *)tty->driver_data;
 441
 442         if (I_IXOFF(tty)) {
 443                 if (info->x_char)
 444                         info->x_char = 0;
 445                 else
 446                         rs_send_xchar(tty, START_CHAR(tty));
 447         }
 448         printk(KERN_INFO "simrs_unthrottle called\n");
 449 }
 450
 451 /*
 452  * rs_break() --- routine which turns the break handling on or off
 453  */
 454 static void rs_break(struct tty_struct *tty, int break_state)
 455 {
 456 }
 457
 458 static int rs_ioctl(struct tty_struct *tty, struct file * file,
 459                     unsigned int cmd, unsigned long arg)
 460 {
 461         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
 462             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
 463             (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
 464                 if (tty->flags & (1 << TTY_IO_ERROR))
 465                     return -EIO;
 466         }
 467
 468         switch (cmd) {
 469                 case TIOCMGET:
 470                         printk(KERN_INFO "rs_ioctl: TIOCMGET called\n");
 471                         return -EINVAL;
 472                 case TIOCMBIS:
 473                 case TIOCMBIC:
 474                 case TIOCMSET:
 475                         printk(KERN_INFO "rs_ioctl: TIOCMBIS/BIC/SET called\n");
 476                         return -EINVAL;
 477                 case TIOCGSERIAL:
 478                         printk(KERN_INFO "simrs_ioctl TIOCGSERIAL called\n");
 479                         return 0;
 480                 case TIOCSSERIAL:
 481                         printk(KERN_INFO "simrs_ioctl TIOCSSERIAL called\n");
 482                         return 0;
 483                 case TIOCSERCONFIG:
 484                         printk(KERN_INFO "rs_ioctl: TIOCSERCONFIG called\n");
 485                         return -EINVAL;
 486
 487                 case TIOCSERGETLSR: /* Get line status register */
 488                         printk(KERN_INFO "rs_ioctl: TIOCSERGETLSR called\n");
 489                         return  -EINVAL;
 490
 491                 case TIOCSERGSTRUCT:
 492                         printk(KERN_INFO "rs_ioctl: TIOCSERGSTRUCT called\n");
 493 #if 0
 494                         if (copy_to_user((struct async_struct *) arg,
 495                                          info, sizeof(struct async_struct)))
 496                                 return -EFAULT;
 497 #endif
 498                         return 0;
 499
 500                 /*
 501                  * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
 502                  * - mask passed in arg for lines of interest
 503                  *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
 504                  * Caller should use TIOCGICOUNT to see which one it was
 505                  */
 506                 case TIOCMIWAIT:
 507                         printk(KERN_INFO "rs_ioctl: TIOCMIWAIT: called\n");
 508                         return 0;
 509                 /*
 510                  * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
 511                  * Return: write counters to the user passed counter struct
 512                  * NB: both 1->0 and 0->1 transitions are counted except for
 513                  *     RI where only 0->1 is counted.
 514                  */
 515                 case TIOCGICOUNT:
 516                         printk(KERN_INFO "rs_ioctl: TIOCGICOUNT called\n");
 517                         return 0;
 518
 519                 case TIOCSERGWILD:
 520                 case TIOCSERSWILD:
 521                         /* "setserial -W" is called in Debian boot */
 522                         printk (KERN_INFO "TIOCSER?WILD ioctl obsolete, ignored.\n");
 523                         return 0;
 524
 525                 default:
 526                         return -ENOIOCTLCMD;
 527                 }
 528         return 0;
 529 }
 530
 531 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 532
 533 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
 534 {
 535         unsigned int cflag = tty->termios->c_cflag;
 536
 537         if (   (cflag == old_termios->c_cflag)
 538             && (   RELEVANT_IFLAG(tty->termios->c_iflag)
 539                 == RELEVANT_IFLAG(old_termios->c_iflag)))
 540           return;
 541
 542
 543         /* Handle turning off CRTSCTS */
 544         if ((old_termios->c_cflag & CRTSCTS) &&
 545             !(tty->termios->c_cflag & CRTSCTS)) {
 546                 tty->hw_stopped = 0;
 547                 rs_start(tty);
 548         }
 549 }
 550 /*
 551  * This routine will shutdown a serial port; interrupts are disabled, and
 552  * DTR is dropped if the hangup on close termio flag is on.
 553  */
 554 static void shutdown(struct async_struct * info)
 555 {
 556         unsigned long   flags;
 557         struct serial_state *state;
 558         int             retval;
 559
 560         if (!(info->flags & ASYNC_INITIALIZED)) return;
 561
 562         state = info->state;
 563
 564 #ifdef SIMSERIAL_DEBUG
 565         printk("Shutting down serial port %d (irq %d)....", info->line,
 566                state->irq);
 567 #endif
 568
 569         local_irq_save(flags);
 570         {
 571                 /*
 572                  * First unlink the serial port from the IRQ chain...
 573                  */
 574                 if (info->next_port)
 575                         info->next_port->prev_port = info->prev_port;
 576                 if (info->prev_port)
 577                         info->prev_port->next_port = info->next_port;
 578                 else
 579                         IRQ_ports[state->irq] = info->next_port;
 580
 581                 /*
 582                  * Free the IRQ, if necessary
 583                  */
 584                 if (state->irq && (!IRQ_ports[state->irq] ||
 585                                    !IRQ_ports[state->irq]->next_port)) {
 586                         if (IRQ_ports[state->irq]) {
 587                                 free_irq(state->irq, NULL);
 588                                 retval = request_irq(state->irq, rs_interrupt_single,
 589                                                      IRQ_T(info), "serial", NULL);
 590
 591                                 if (retval)
 592                                         printk(KERN_ERR "serial shutdown: request_irq: error %d"
 593                                                "  Couldn't reacquire IRQ.\n", retval);
 594                         } else
 595                                 free_irq(state->irq, NULL);
 596                 }
 597
 598                 if (info->xmit.buf) {
 599                         free_page((unsigned long) info->xmit.buf);
 600                         info->xmit.buf = 0;
 601                 }
 602
 603                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
 604
 605                 info->flags &= ~ASYNC_INITIALIZED;
 606         }
 607         local_irq_restore(flags);
 608 }
 609
 610 /*
 611  * ------------------------------------------------------------
 612  * rs_close()
 613  *
 614  * This routine is called when the serial port gets closed.  First, we
 615  * wait for the last remaining data to be sent.  Then, we unlink its
 616  * async structure from the interrupt chain if necessary, and we free
 617  * that IRQ if nothing is left in the chain.
 618  * ------------------------------------------------------------
 619  */
 620 static void rs_close(struct tty_struct *tty, struct file * filp)
 621 {
 622         struct async_struct * info = (struct async_struct *)tty->driver_data;
 623         struct serial_state *state;
 624         unsigned long flags;
 625
 626         if (!info ) return;
 627
 628         state = info->state;
 629
 630         local_irq_save(flags);
 631         if (tty_hung_up_p(filp)) {
 632 #ifdef SIMSERIAL_DEBUG
 633                 printk("rs_close: hung_up\n");
 634 #endif
 635                 local_irq_restore(flags);
 636                 return;
 637         }
 638 #ifdef SIMSERIAL_DEBUG
 639         printk("rs_close ttys%d, count = %d\n", info->line, state->count);
 640 #endif
 641         if ((tty->count == 1) && (state->count != 1)) {
 642                 /*
 643                  * Uh, oh.  tty->count is 1, which means that the tty
 644                  * structure will be freed.  state->count should always
 645                  * be one in these conditions.  If it's greater than
 646                  * one, we've got real problems, since it means the
 647                  * serial port won't be shutdown.
 648                  */
 649                 printk(KERN_ERR "rs_close: bad serial port count; tty->count is 1, "
 650                        "state->count is %d\n", state->count);
 651                 state->count = 1;
 652         }
 653         if (--state->count < 0) {
 654                 printk(KERN_ERR "rs_close: bad serial port count for ttys%d: %d\n",
 655                        info->line, state->count);
 656                 state->count = 0;
 657         }
 658         if (state->count) {
 659                 local_irq_restore(flags);
 660                 return;
 661         }
 662         info->flags |= ASYNC_CLOSING;
 663         local_irq_restore(flags);
 664
 665         /*
 666          * Now we wait for the transmit buffer to clear; and we notify
 667          * the line discipline to only process XON/XOFF characters.
 668          */
 669         shutdown(info);
 670         if (tty->driver->flush_buffer) tty->driver->flush_buffer(tty);
 671         if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty);
 672         info->event = 0;
 673         info->tty = 0;
 674         if (info->blocked_open) {
 675                 if (info->close_delay) {
 676                         current->state = TASK_INTERRUPTIBLE;
 677                         schedule_timeout(info->close_delay);
 678                 }
 679                 wake_up_interruptible(&info->open_wait);
 680         }
 681         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
 682         wake_up_interruptible(&info->close_wait);
 683 }
 684
 685 /*
 686  * rs_wait_until_sent() --- wait until the transmitter is empty
 687  */
 688 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
 689 {
 690 }
 691
 692
 693 /*
 694  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 695  */
 696 static void rs_hangup(struct tty_struct *tty)
 697 {
 698         struct async_struct * info = (struct async_struct *)tty->driver_data;
 699         struct serial_state *state = info->state;
 700
 701 #ifdef SIMSERIAL_DEBUG
 702         printk("rs_hangup: called\n");
 703 #endif
 704
 705         state = info->state;
 706
 707         rs_flush_buffer(tty);
 708         if (info->flags & ASYNC_CLOSING)
 709                 return;
 710         shutdown(info);
 711
 712         info->event = 0;
 713         state->count = 0;
 714         info->flags &= ~ASYNC_NORMAL_ACTIVE;
 715         info->tty = 0;
 716         wake_up_interruptible(&info->open_wait);
 717 }
 718
 719
 720 static int get_async_struct(int line, struct async_struct **ret_info)
 721 {
 722         struct async_struct *info;
 723         struct serial_state *sstate;
 724
 725         sstate = rs_table + line;
 726         sstate->count++;
 727         if (sstate->info) {
 728                 *ret_info = sstate->info;
 729                 return 0;
 730         }
 731         info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
 732         if (!info) {
 733                 sstate->count--;
 734                 return -ENOMEM;
 735         }
 736         memset(info, 0, sizeof(struct async_struct));
 737         init_waitqueue_head(&info->open_wait);
 738         init_waitqueue_head(&info->close_wait);
 739         init_waitqueue_head(&info->delta_msr_wait);
 740         info->magic = SERIAL_MAGIC;
 741         info->port = sstate->port;
 742         info->flags = sstate->flags;
 743         info->xmit_fifo_size = sstate->xmit_fifo_size;
 744         info->line = line;
 745         INIT_WORK(&info->work, do_softint, info);
 746         info->state = sstate;
 747         if (sstate->info) {
 748                 kfree(info);
 749                 *ret_info = sstate->info;
 750                 return 0;
 751         }
 752         *ret_info = sstate->info = info;
 753         return 0;
 754 }
 755
 756 static int
 757 startup(struct async_struct *info)
 758 {
 759         unsigned long flags;
 760         int     retval=0;
 761         irqreturn_t (*handler)(int, void *, struct pt_regs *);
 762         struct serial_state *state= info->state;
 763         unsigned long page;
 764
 765         page = get_zeroed_page(GFP_KERNEL);
 766         if (!page)
 767                 return -ENOMEM;
 768
 769         local_irq_save(flags);
 770
 771         if (info->flags & ASYNC_INITIALIZED) {
 772                 free_page(page);
 773                 goto errout;
 774         }
 775
 776         if (!state->port || !state->type) {
 777                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
 778                 free_page(page);
 779                 goto errout;
 780         }
 781         if (info->xmit.buf)
 782                 free_page(page);
 783         else
 784                 info->xmit.buf = (unsigned char *) page;
 785
 786 #ifdef SIMSERIAL_DEBUG
 787         printk("startup: ttys%d (irq %d)...", info->line, state->irq);
 788 #endif
 789
 790         /*
 791          * Allocate the IRQ if necessary
 792          */
 793         if (state->irq && (!IRQ_ports[state->irq] ||
 794                           !IRQ_ports[state->irq]->next_port)) {
 795                 if (IRQ_ports[state->irq]) {
 796                         retval = -EBUSY;
 797                         goto errout;
 798                 } else
 799                         handler = rs_interrupt_single;
 800
 801                 retval = request_irq(state->irq, handler, IRQ_T(info), "simserial", NULL);
 802                 if (retval) {
 803                         if (capable(CAP_SYS_ADMIN)) {
 804                                 if (info->tty)
 805                                         set_bit(TTY_IO_ERROR,
 806                                                 &info->tty->flags);
 807                                 retval = 0;
 808                         }
 809                         goto errout;
 810                 }
 811         }
 812
 813         /*
 814          * Insert serial port into IRQ chain.
 815          */
 816         info->prev_port = 0;
 817         info->next_port = IRQ_ports[state->irq];
 818         if (info->next_port)
 819                 info->next_port->prev_port = info;
 820         IRQ_ports[state->irq] = info;
 821
 822         if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags);
 823
 824         info->xmit.head = info->xmit.tail = 0;
 825
 826 #if 0
 827         /*
 828          * Set up serial timers...
 829          */
 830         timer_table[RS_TIMER].expires = jiffies + 2*HZ/100;
 831         timer_active |= 1 << RS_TIMER;
 832 #endif
 833
 834         /*
 835          * Set up the tty->alt_speed kludge
 836          */
 837         if (info->tty) {
 838                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
 839                         info->tty->alt_speed = 57600;
 840                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
 841                         info->tty->alt_speed = 115200;
 842                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
 843                         info->tty->alt_speed = 230400;
 844                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
 845                         info->tty->alt_speed = 460800;
 846         }
 847
 848         info->flags |= ASYNC_INITIALIZED;
 849         local_irq_restore(flags);
 850         return 0;
 851
 852 errout:
 853         local_irq_restore(flags);
 854         return retval;
 855 }
 856
 857
 858 /*
 859  * This routine is called whenever a serial port is opened.  It
 860  * enables interrupts for a serial port, linking in its async structure into
 861  * the IRQ chain.   It also performs the serial-specific
 862  * initialization for the tty structure.
 863  */
 864 static int rs_open(struct tty_struct *tty, struct file * filp)
 865 {
 866         struct async_struct     *info;
 867         int                     retval, line;
 868         unsigned long           page;
 869
 870         line = tty->index;
 871         if ((line < 0) || (line >= NR_PORTS))
 872                 return -ENODEV;
 873         retval = get_async_struct(line, &info);
 874         if (retval)
 875                 return retval;
 876         tty->driver_data = info;
 877         info->tty = tty;
 878
 879 #ifdef SIMSERIAL_DEBUG
 880         printk("rs_open %s, count = %d\n", tty->name, info->state->count);
 881 #endif
 882         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 883
 884         if (!tmp_buf) {
 885                 page = get_zeroed_page(GFP_KERNEL);
 886                 if (!page)
 887                         return -ENOMEM;
 888                 if (tmp_buf)
 889                         free_page(page);
 890                 else
 891                         tmp_buf = (unsigned char *) page;
 892         }
 893
 894         /*
 895          * If the port is the middle of closing, bail out now
 896          */
 897         if (tty_hung_up_p(filp) ||
 898             (info->flags & ASYNC_CLOSING)) {
 899                 if (info->flags & ASYNC_CLOSING)
 900                         interruptible_sleep_on(&info->close_wait);
 901 #ifdef SERIAL_DO_RESTART
 902                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
 903                         -EAGAIN : -ERESTARTSYS);
 904 #else
 905                 return -EAGAIN;
 906 #endif
 907         }
 908
 909         /*
 910          * Start up serial port
 911          */
 912         retval = startup(info);
 913         if (retval) {
 914                 return retval;
 915         }
 916
 917         /*
 918          * figure out which console to use (should be one already)
 919          */
 920         console = console_drivers;
 921         while (console) {
 922                 if ((console->flags & CON_ENABLED) && console->write) break;
 923                 console = console->next;
 924         }
 925
 926 #ifdef SIMSERIAL_DEBUG
 927         printk("rs_open ttys%d successful\n", info->line);
 928 #endif
 929         return 0;
 930 }
 931
 932 /*
 933  * /proc fs routines....
 934  */
 935
 936 static inline int line_info(char *buf, struct serial_state *state)
 937 {
 938         return sprintf(buf, "%d: uart:%s port:%lX irq:%d\n",
 939                        state->line, uart_config[state->type].name,
 940                        state->port, state->irq);
 941 }
 942
 943 static int rs_read_proc(char *page, char **start, off_t off, int count,
 944                  int *eof, void *data)
 945 {
 946         int i, len = 0, l;
 947         off_t   begin = 0;
 948
 949         len += sprintf(page, "simserinfo:1.0 driver:%s\n", serial_version);
 950         for (i = 0; i < NR_PORTS && len < 4000; i++) {
 951                 l = line_info(page + len, &rs_table[i]);
 952                 len += l;
 953                 if (len+begin > off+count)
 954                         goto done;
 955                 if (len+begin < off) {
 956                         begin += len;
 957                         len = 0;
 958                 }
 959         }
 960         *eof = 1;
 961 done:
 962         if (off >= len+begin)
 963                 return 0;
 964         *start = page + (begin-off);
 965         return ((count < begin+len-off) ? count : begin+len-off);
 966 }
 967
 968 /*
 969  * ---------------------------------------------------------------------
 970  * rs_init() and friends
 971  *
 972  * rs_init() is called at boot-time to initialize the serial driver.
 973  * ---------------------------------------------------------------------
 974  */
 975
 976 /*
 977  * This routine prints out the appropriate serial driver version
 978  * number, and identifies which options were configured into this
 979  * driver.
 980  */
 981 static inline void show_serial_version(void)
 982 {
 983         printk(KERN_INFO "%s version %s with", serial_name, serial_version);
 984         printk(KERN_INFO " no serial options enabled\n");
 985 }
 986
 987 static struct tty_operations hp_ops = {
 988         .open = rs_open,
 989         .close = rs_close,
 990         .write = rs_write,
 991         .put_char = rs_put_char,
 992         .flush_chars = rs_flush_chars,
 993         .write_room = rs_write_room,
 994         .chars_in_buffer = rs_chars_in_buffer,
 995         .flush_buffer = rs_flush_buffer,
 996         .ioctl = rs_ioctl,
 997         .throttle = rs_throttle,
 998         .unthrottle = rs_unthrottle,
 999         .send_xchar = rs_send_xchar,
1000         .set_termios = rs_set_termios,
1001         .stop = rs_stop,
1002         .start = rs_start,
1003         .hangup = rs_hangup,
1004         .break_ctl = rs_break,
1005         .wait_until_sent = rs_wait_until_sent,
1006         .read_proc = rs_read_proc,
1007 };
1008
1009 /*
1010  * The serial driver boot-time initialization code!
1011  */
1012 static int __init
1013 simrs_init (void)
1014 {
1015         int                     i;
1016         struct serial_state     *state;
1017
1018         if (!ia64_platform_is("hpsim"))
1019                 return -ENODEV;
1020
1021         hp_simserial_driver = alloc_tty_driver(1);
1022         if (!hp_simserial_driver)
1023                 return -ENOMEM;
1024
1025         show_serial_version();
1026
1027         /* Initialize the tty_driver structure */
1028
1029         hp_simserial_driver->owner = THIS_MODULE;
1030         hp_simserial_driver->driver_name = "simserial";
1031         hp_simserial_driver->name = "ttyS";
1032         hp_simserial_driver->major = TTY_MAJOR;
1033         hp_simserial_driver->minor_start = 64;
1034         hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1035         hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
1036         hp_simserial_driver->init_termios = tty_std_termios;
1037         hp_simserial_driver->init_termios.c_cflag =
1038                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1039         hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
1040         tty_set_operations(hp_simserial_driver, &hp_ops);
1041
1042         /*
1043          * Let's have a little bit of fun !
1044          */
1045         for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
1046
1047                 if (state->type == PORT_UNKNOWN) continue;
1048
1049                 if (!state->irq) {
1050                         state->irq = assign_irq_vector(AUTO_ASSIGN);
1051                         ia64_ssc_connect_irq(KEYBOARD_INTR, state->irq);
1052                 }
1053
1054                 printk(KERN_INFO "ttyS%d at 0x%04lx (irq = %d) is a %s\n",
1055                        state->line,
1056                        state->port, state->irq,
1057                        uart_config[state->type].name);
1058         }
1059
1060         if (tty_register_driver(hp_simserial_driver))
1061                 panic("Couldn't register simserial driver\n");
1062
1063         return 0;
1064 }
1065
1066 #ifndef MODULE
1067 __initcall(simrs_init);
1068 #endif