git.oblomov.eu Git - linux-2.6/blob - 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/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 #ifdef CONFIG_KDB
  41 # include <linux/kdb.h>
  42 #endif
  43
  44 #undef SIMSERIAL_DEBUG  /* define this to get some debug information */
  45
  46 #define KEYBOARD_INTR   3       /* must match with simulator! */
  47
  48 #define NR_PORTS        1       /* only one port for now */
  49 #define SERIAL_INLINE   1
  50
  51 #ifdef SERIAL_INLINE
  52 #define _INLINE_ inline
  53 #endif
  54
  55 #define IRQ_T(info) ((info->flags & ASYNC_SHARE_IRQ) ? SA_SHIRQ : SA_INTERRUPT)
  56
  57 #define SSC_GETCHAR     21
  58
  59 extern long ia64_ssc (long, long, long, long, int);
  60 extern void ia64_ssc_connect_irq (long intr, long irq);
  61
  62 static char *serial_name = "SimSerial driver";
  63 static char *serial_version = "0.6";
  64
  65 /*
  66  * This has been extracted from asm/serial.h. We need one eventually but
  67  * I don't know exactly what we're going to put in it so just fake one
  68  * for now.
  69  */
  70 #define BASE_BAUD ( 1843200 / 16 )
  71
  72 #define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
  73
  74 /*
  75  * Most of the values here are meaningless to this particular driver.
  76  * However some values must be preserved for the code (leveraged from serial.c
  77  * to work correctly).
  78  * port must not be 0
  79  * type must not be UNKNOWN
  80  * So I picked arbitrary (guess from where?) values instead
  81  */
  82 static struct serial_state rs_table[NR_PORTS]={
  83   /* UART CLK   PORT IRQ     FLAGS        */
  84   { 0, BASE_BAUD, 0x3F8, 0, STD_COM_FLAGS,0,PORT_16550 }  /* ttyS0 */
  85 };
  86
  87 /*
  88  * Just for the fun of it !
  89  */
  90 static struct serial_uart_config uart_config[] = {
  91         { "unknown", 1, 0 },
  92         { "8250", 1, 0 },
  93         { "16450", 1, 0 },
  94         { "16550", 1, 0 },
  95         { "16550A", 16, UART_CLEAR_FIFO | UART_USE_FIFO },
  96         { "cirrus", 1, 0 },
  97         { "ST16650", 1, UART_CLEAR_FIFO | UART_STARTECH },
  98         { "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO |
  99                   UART_STARTECH },
 100         { "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO},
 101         { 0, 0}
 102 };
 103
 104 struct tty_driver *hp_simserial_driver;
 105
 106 static struct async_struct *IRQ_ports[NR_IRQS];
 107
 108 static struct console *console;
 109
 110 static unsigned char *tmp_buf;
 111
 112 extern struct console *console_drivers; /* from kernel/printk.c */
 113
 114 /*
 115  * ------------------------------------------------------------
 116  * rs_stop() and rs_start()
 117  *
 118  * This routines are called before setting or resetting tty->stopped.
 119  * They enable or disable transmitter interrupts, as necessary.
 120  * ------------------------------------------------------------
 121  */
 122 static void rs_stop(struct tty_struct *tty)
 123 {
 124 #ifdef SIMSERIAL_DEBUG
 125         printk("rs_stop: 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
 131 static void rs_start(struct tty_struct *tty)
 132 {
 133 #ifdef SIMSERIAL_DEBUG
 134         printk("rs_start: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
 135                 tty->stopped, tty->hw_stopped, tty->flow_stopped);
 136 #endif
 137 }
 138
 139 static  void receive_chars(struct tty_struct *tty, struct pt_regs *regs)
 140 {
 141         unsigned char ch;
 142         static unsigned char seen_esc = 0;
 143
 144         while ( (ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR)) ) {
 145                 if ( ch == 27 && seen_esc == 0 ) {
 146                         seen_esc = 1;
 147                         continue;
 148                 } else {
 149                         if ( seen_esc==1 && ch == 'O' ) {
 150                                 seen_esc = 2;
 151                                 continue;
 152                         } else if ( seen_esc == 2 ) {
 153                                 if ( ch == 'P' ) /* F1 */
 154                                         show_state();
 155 #ifdef CONFIG_MAGIC_SYSRQ
 156                                 if ( ch == 'S' ) { /* F4 */
 157                                         do
 158                                                 ch = ia64_ssc(0, 0, 0, 0,
 159                                                               SSC_GETCHAR);
 160                                         while (!ch);
 161                                         handle_sysrq(ch, regs, NULL);
 162                                 }
 163 #endif
 164                                 seen_esc = 0;
 165                                 continue;
 166                         }
 167                 }
 168                 seen_esc = 0;
 169
 170                 if (tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0)
 171                         break;
 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,
 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         local_irq_save(flags);
 314         while (1) {
 315                 c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 316                 if (count < c)
 317                         c = count;
 318                 if (c <= 0) {
 319                         break;
 320                 }
 321                 memcpy(info->xmit.buf + info->xmit.head, buf, c);
 322                 info->xmit.head = ((info->xmit.head + c) &
 323                                    (SERIAL_XMIT_SIZE-1));
 324                 buf += c;
 325                 count -= c;
 326                 ret += c;
 327         }
 328         local_irq_restore(flags);
 329         /*
 330          * Hey, we transmit directly from here in our case
 331          */
 332         if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE)
 333             && !tty->stopped && !tty->hw_stopped) {
 334                 transmit_chars(info, NULL);
 335         }
 336         return ret;
 337 }
 338
 339 static int rs_write_room(struct tty_struct *tty)
 340 {
 341         struct async_struct *info = (struct async_struct *)tty->driver_data;
 342
 343         return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 344 }
 345
 346 static int rs_chars_in_buffer(struct tty_struct *tty)
 347 {
 348         struct async_struct *info = (struct async_struct *)tty->driver_data;
 349
 350         return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
 351 }
 352
 353 static void rs_flush_buffer(struct tty_struct *tty)
 354 {
 355         struct async_struct *info = (struct async_struct *)tty->driver_data;
 356         unsigned long flags;
 357
 358         local_irq_save(flags);
 359         info->xmit.head = info->xmit.tail = 0;
 360         local_irq_restore(flags);
 361
 362         wake_up_interruptible(&tty->write_wait);
 363
 364         if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
 365             tty->ldisc.write_wakeup)
 366                 (tty->ldisc.write_wakeup)(tty);
 367 }
 368
 369 /*
 370  * This function is used to send a high-priority XON/XOFF character to
 371  * the device
 372  */
 373 static void rs_send_xchar(struct tty_struct *tty, char ch)
 374 {
 375         struct async_struct *info = (struct async_struct *)tty->driver_data;
 376
 377         info->x_char = ch;
 378         if (ch) {
 379                 /*
 380                  * I guess we could call console->write() directly but
 381                  * let's do that for now.
 382                  */
 383                 transmit_chars(info, NULL);
 384         }
 385 }
 386
 387 /*
 388  * ------------------------------------------------------------
 389  * rs_throttle()
 390  *
 391  * This routine is called by the upper-layer tty layer to signal that
 392  * incoming characters should be throttled.
 393  * ------------------------------------------------------------
 394  */
 395 static void rs_throttle(struct tty_struct * tty)
 396 {
 397         if (I_IXOFF(tty)) rs_send_xchar(tty, STOP_CHAR(tty));
 398
 399         printk(KERN_INFO "simrs_throttle called\n");
 400 }
 401
 402 static void rs_unthrottle(struct tty_struct * tty)
 403 {
 404         struct async_struct *info = (struct async_struct *)tty->driver_data;
 405
 406         if (I_IXOFF(tty)) {
 407                 if (info->x_char)
 408                         info->x_char = 0;
 409                 else
 410                         rs_send_xchar(tty, START_CHAR(tty));
 411         }
 412         printk(KERN_INFO "simrs_unthrottle called\n");
 413 }
 414
 415 /*
 416  * rs_break() --- routine which turns the break handling on or off
 417  */
 418 static void rs_break(struct tty_struct *tty, int break_state)
 419 {
 420 }
 421
 422 static int rs_ioctl(struct tty_struct *tty, struct file * file,
 423                     unsigned int cmd, unsigned long arg)
 424 {
 425         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
 426             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
 427             (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
 428                 if (tty->flags & (1 << TTY_IO_ERROR))
 429                     return -EIO;
 430         }
 431
 432         switch (cmd) {
 433                 case TIOCMGET:
 434                         printk(KERN_INFO "rs_ioctl: TIOCMGET called\n");
 435                         return -EINVAL;
 436                 case TIOCMBIS:
 437                 case TIOCMBIC:
 438                 case TIOCMSET:
 439                         printk(KERN_INFO "rs_ioctl: TIOCMBIS/BIC/SET called\n");
 440                         return -EINVAL;
 441                 case TIOCGSERIAL:
 442                         printk(KERN_INFO "simrs_ioctl TIOCGSERIAL called\n");
 443                         return 0;
 444                 case TIOCSSERIAL:
 445                         printk(KERN_INFO "simrs_ioctl TIOCSSERIAL called\n");
 446                         return 0;
 447                 case TIOCSERCONFIG:
 448                         printk(KERN_INFO "rs_ioctl: TIOCSERCONFIG called\n");
 449                         return -EINVAL;
 450
 451                 case TIOCSERGETLSR: /* Get line status register */
 452                         printk(KERN_INFO "rs_ioctl: TIOCSERGETLSR called\n");
 453                         return  -EINVAL;
 454
 455                 case TIOCSERGSTRUCT:
 456                         printk(KERN_INFO "rs_ioctl: TIOCSERGSTRUCT called\n");
 457 #if 0
 458                         if (copy_to_user((struct async_struct *) arg,
 459                                          info, sizeof(struct async_struct)))
 460                                 return -EFAULT;
 461 #endif
 462                         return 0;
 463
 464                 /*
 465                  * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
 466                  * - mask passed in arg for lines of interest
 467                  *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
 468                  * Caller should use TIOCGICOUNT to see which one it was
 469                  */
 470                 case TIOCMIWAIT:
 471                         printk(KERN_INFO "rs_ioctl: TIOCMIWAIT: called\n");
 472                         return 0;
 473                 /*
 474                  * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
 475                  * Return: write counters to the user passed counter struct
 476                  * NB: both 1->0 and 0->1 transitions are counted except for
 477                  *     RI where only 0->1 is counted.
 478                  */
 479                 case TIOCGICOUNT:
 480                         printk(KERN_INFO "rs_ioctl: TIOCGICOUNT called\n");
 481                         return 0;
 482
 483                 case TIOCSERGWILD:
 484                 case TIOCSERSWILD:
 485                         /* "setserial -W" is called in Debian boot */
 486                         printk (KERN_INFO "TIOCSER?WILD ioctl obsolete, ignored.\n");
 487                         return 0;
 488
 489                 default:
 490                         return -ENOIOCTLCMD;
 491                 }
 492         return 0;
 493 }
 494
 495 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 496
 497 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
 498 {
 499         unsigned int cflag = tty->termios->c_cflag;
 500
 501         if (   (cflag == old_termios->c_cflag)
 502             && (   RELEVANT_IFLAG(tty->termios->c_iflag)
 503                 == RELEVANT_IFLAG(old_termios->c_iflag)))
 504           return;
 505
 506
 507         /* Handle turning off CRTSCTS */
 508         if ((old_termios->c_cflag & CRTSCTS) &&
 509             !(tty->termios->c_cflag & CRTSCTS)) {
 510                 tty->hw_stopped = 0;
 511                 rs_start(tty);
 512         }
 513 }
 514 /*
 515  * This routine will shutdown a serial port; interrupts are disabled, and
 516  * DTR is dropped if the hangup on close termio flag is on.
 517  */
 518 static void shutdown(struct async_struct * info)
 519 {
 520         unsigned long   flags;
 521         struct serial_state *state;
 522         int             retval;
 523
 524         if (!(info->flags & ASYNC_INITIALIZED)) return;
 525
 526         state = info->state;
 527
 528 #ifdef SIMSERIAL_DEBUG
 529         printk("Shutting down serial port %d (irq %d)....", info->line,
 530                state->irq);
 531 #endif
 532
 533         local_irq_save(flags);
 534         {
 535                 /*
 536                  * First unlink the serial port from the IRQ chain...
 537                  */
 538                 if (info->next_port)
 539                         info->next_port->prev_port = info->prev_port;
 540                 if (info->prev_port)
 541                         info->prev_port->next_port = info->next_port;
 542                 else
 543                         IRQ_ports[state->irq] = info->next_port;
 544
 545                 /*
 546                  * Free the IRQ, if necessary
 547                  */
 548                 if (state->irq && (!IRQ_ports[state->irq] ||
 549                                    !IRQ_ports[state->irq]->next_port)) {
 550                         if (IRQ_ports[state->irq]) {
 551                                 free_irq(state->irq, NULL);
 552                                 retval = request_irq(state->irq, rs_interrupt_single,
 553                                                      IRQ_T(info), "serial", NULL);
 554
 555                                 if (retval)
 556                                         printk(KERN_ERR "serial shutdown: request_irq: error %d"
 557                                                "  Couldn't reacquire IRQ.\n", retval);
 558                         } else
 559                                 free_irq(state->irq, NULL);
 560                 }
 561
 562                 if (info->xmit.buf) {
 563                         free_page((unsigned long) info->xmit.buf);
 564                         info->xmit.buf = 0;
 565                 }
 566
 567                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
 568
 569                 info->flags &= ~ASYNC_INITIALIZED;
 570         }
 571         local_irq_restore(flags);
 572 }
 573
 574 /*
 575  * ------------------------------------------------------------
 576  * rs_close()
 577  *
 578  * This routine is called when the serial port gets closed.  First, we
 579  * wait for the last remaining data to be sent.  Then, we unlink its
 580  * async structure from the interrupt chain if necessary, and we free
 581  * that IRQ if nothing is left in the chain.
 582  * ------------------------------------------------------------
 583  */
 584 static void rs_close(struct tty_struct *tty, struct file * filp)
 585 {
 586         struct async_struct * info = (struct async_struct *)tty->driver_data;
 587         struct serial_state *state;
 588         unsigned long flags;
 589
 590         if (!info ) return;
 591
 592         state = info->state;
 593
 594         local_irq_save(flags);
 595         if (tty_hung_up_p(filp)) {
 596 #ifdef SIMSERIAL_DEBUG
 597                 printk("rs_close: hung_up\n");
 598 #endif
 599                 local_irq_restore(flags);
 600                 return;
 601         }
 602 #ifdef SIMSERIAL_DEBUG
 603         printk("rs_close ttys%d, count = %d\n", info->line, state->count);
 604 #endif
 605         if ((tty->count == 1) && (state->count != 1)) {
 606                 /*
 607                  * Uh, oh.  tty->count is 1, which means that the tty
 608                  * structure will be freed.  state->count should always
 609                  * be one in these conditions.  If it's greater than
 610                  * one, we've got real problems, since it means the
 611                  * serial port won't be shutdown.
 612                  */
 613                 printk(KERN_ERR "rs_close: bad serial port count; tty->count is 1, "
 614                        "state->count is %d\n", state->count);
 615                 state->count = 1;
 616         }
 617         if (--state->count < 0) {
 618                 printk(KERN_ERR "rs_close: bad serial port count for ttys%d: %d\n",
 619                        info->line, state->count);
 620                 state->count = 0;
 621         }
 622         if (state->count) {
 623                 local_irq_restore(flags);
 624                 return;
 625         }
 626         info->flags |= ASYNC_CLOSING;
 627         local_irq_restore(flags);
 628
 629         /*
 630          * Now we wait for the transmit buffer to clear; and we notify
 631          * the line discipline to only process XON/XOFF characters.
 632          */
 633         shutdown(info);
 634         if (tty->driver->flush_buffer) tty->driver->flush_buffer(tty);
 635         if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty);
 636         info->event = 0;
 637         info->tty = 0;
 638         if (info->blocked_open) {
 639                 if (info->close_delay)
 640                         schedule_timeout_interruptible(info->close_delay);
 641                 wake_up_interruptible(&info->open_wait);
 642         }
 643         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
 644         wake_up_interruptible(&info->close_wait);
 645 }
 646
 647 /*
 648  * rs_wait_until_sent() --- wait until the transmitter is empty
 649  */
 650 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
 651 {
 652 }
 653
 654
 655 /*
 656  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 657  */
 658 static void rs_hangup(struct tty_struct *tty)
 659 {
 660         struct async_struct * info = (struct async_struct *)tty->driver_data;
 661         struct serial_state *state = info->state;
 662
 663 #ifdef SIMSERIAL_DEBUG
 664         printk("rs_hangup: called\n");
 665 #endif
 666
 667         state = info->state;
 668
 669         rs_flush_buffer(tty);
 670         if (info->flags & ASYNC_CLOSING)
 671                 return;
 672         shutdown(info);
 673
 674         info->event = 0;
 675         state->count = 0;
 676         info->flags &= ~ASYNC_NORMAL_ACTIVE;
 677         info->tty = 0;
 678         wake_up_interruptible(&info->open_wait);
 679 }
 680
 681
 682 static int get_async_struct(int line, struct async_struct **ret_info)
 683 {
 684         struct async_struct *info;
 685         struct serial_state *sstate;
 686
 687         sstate = rs_table + line;
 688         sstate->count++;
 689         if (sstate->info) {
 690                 *ret_info = sstate->info;
 691                 return 0;
 692         }
 693         info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
 694         if (!info) {
 695                 sstate->count--;
 696                 return -ENOMEM;
 697         }
 698         memset(info, 0, sizeof(struct async_struct));
 699         init_waitqueue_head(&info->open_wait);
 700         init_waitqueue_head(&info->close_wait);
 701         init_waitqueue_head(&info->delta_msr_wait);
 702         info->magic = SERIAL_MAGIC;
 703         info->port = sstate->port;
 704         info->flags = sstate->flags;
 705         info->xmit_fifo_size = sstate->xmit_fifo_size;
 706         info->line = line;
 707         INIT_WORK(&info->work, do_softint, info);
 708         info->state = sstate;
 709         if (sstate->info) {
 710                 kfree(info);
 711                 *ret_info = sstate->info;
 712                 return 0;
 713         }
 714         *ret_info = sstate->info = info;
 715         return 0;
 716 }
 717
 718 static int
 719 startup(struct async_struct *info)
 720 {
 721         unsigned long flags;
 722         int     retval=0;
 723         irqreturn_t (*handler)(int, void *, struct pt_regs *);
 724         struct serial_state *state= info->state;
 725         unsigned long page;
 726
 727         page = get_zeroed_page(GFP_KERNEL);
 728         if (!page)
 729                 return -ENOMEM;
 730
 731         local_irq_save(flags);
 732
 733         if (info->flags & ASYNC_INITIALIZED) {
 734                 free_page(page);
 735                 goto errout;
 736         }
 737
 738         if (!state->port || !state->type) {
 739                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
 740                 free_page(page);
 741                 goto errout;
 742         }
 743         if (info->xmit.buf)
 744                 free_page(page);
 745         else
 746                 info->xmit.buf = (unsigned char *) page;
 747
 748 #ifdef SIMSERIAL_DEBUG
 749         printk("startup: ttys%d (irq %d)...", info->line, state->irq);
 750 #endif
 751
 752         /*
 753          * Allocate the IRQ if necessary
 754          */
 755         if (state->irq && (!IRQ_ports[state->irq] ||
 756                           !IRQ_ports[state->irq]->next_port)) {
 757                 if (IRQ_ports[state->irq]) {
 758                         retval = -EBUSY;
 759                         goto errout;
 760                 } else
 761                         handler = rs_interrupt_single;
 762
 763                 retval = request_irq(state->irq, handler, IRQ_T(info), "simserial", NULL);
 764                 if (retval) {
 765                         if (capable(CAP_SYS_ADMIN)) {
 766                                 if (info->tty)
 767                                         set_bit(TTY_IO_ERROR,
 768                                                 &info->tty->flags);
 769                                 retval = 0;
 770                         }
 771                         goto errout;
 772                 }
 773         }
 774
 775         /*
 776          * Insert serial port into IRQ chain.
 777          */
 778         info->prev_port = 0;
 779         info->next_port = IRQ_ports[state->irq];
 780         if (info->next_port)
 781                 info->next_port->prev_port = info;
 782         IRQ_ports[state->irq] = info;
 783
 784         if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags);
 785
 786         info->xmit.head = info->xmit.tail = 0;
 787
 788 #if 0
 789         /*
 790          * Set up serial timers...
 791          */
 792         timer_table[RS_TIMER].expires = jiffies + 2*HZ/100;
 793         timer_active |= 1 << RS_TIMER;
 794 #endif
 795
 796         /*
 797          * Set up the tty->alt_speed kludge
 798          */
 799         if (info->tty) {
 800                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
 801                         info->tty->alt_speed = 57600;
 802                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
 803                         info->tty->alt_speed = 115200;
 804                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
 805                         info->tty->alt_speed = 230400;
 806                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
 807                         info->tty->alt_speed = 460800;
 808         }
 809
 810         info->flags |= ASYNC_INITIALIZED;
 811         local_irq_restore(flags);
 812         return 0;
 813
 814 errout:
 815         local_irq_restore(flags);
 816         return retval;
 817 }
 818
 819
 820 /*
 821  * This routine is called whenever a serial port is opened.  It
 822  * enables interrupts for a serial port, linking in its async structure into
 823  * the IRQ chain.   It also performs the serial-specific
 824  * initialization for the tty structure.
 825  */
 826 static int rs_open(struct tty_struct *tty, struct file * filp)
 827 {
 828         struct async_struct     *info;
 829         int                     retval, line;
 830         unsigned long           page;
 831
 832         line = tty->index;
 833         if ((line < 0) || (line >= NR_PORTS))
 834                 return -ENODEV;
 835         retval = get_async_struct(line, &info);
 836         if (retval)
 837                 return retval;
 838         tty->driver_data = info;
 839         info->tty = tty;
 840
 841 #ifdef SIMSERIAL_DEBUG
 842         printk("rs_open %s, count = %d\n", tty->name, info->state->count);
 843 #endif
 844         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 845
 846         if (!tmp_buf) {
 847                 page = get_zeroed_page(GFP_KERNEL);
 848                 if (!page)
 849                         return -ENOMEM;
 850                 if (tmp_buf)
 851                         free_page(page);
 852                 else
 853                         tmp_buf = (unsigned char *) page;
 854         }
 855
 856         /*
 857          * If the port is the middle of closing, bail out now
 858          */
 859         if (tty_hung_up_p(filp) ||
 860             (info->flags & ASYNC_CLOSING)) {
 861                 if (info->flags & ASYNC_CLOSING)
 862                         interruptible_sleep_on(&info->close_wait);
 863 #ifdef SERIAL_DO_RESTART
 864                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
 865                         -EAGAIN : -ERESTARTSYS);
 866 #else
 867                 return -EAGAIN;
 868 #endif
 869         }
 870
 871         /*
 872          * Start up serial port
 873          */
 874         retval = startup(info);
 875         if (retval) {
 876                 return retval;
 877         }
 878
 879         /*
 880          * figure out which console to use (should be one already)
 881          */
 882         console = console_drivers;
 883         while (console) {
 884                 if ((console->flags & CON_ENABLED) && console->write) break;
 885                 console = console->next;
 886         }
 887
 888 #ifdef SIMSERIAL_DEBUG
 889         printk("rs_open ttys%d successful\n", info->line);
 890 #endif
 891         return 0;
 892 }
 893
 894 /*
 895  * /proc fs routines....
 896  */
 897
 898 static inline int line_info(char *buf, struct serial_state *state)
 899 {
 900         return sprintf(buf, "%d: uart:%s port:%lX irq:%d\n",
 901                        state->line, uart_config[state->type].name,
 902                        state->port, state->irq);
 903 }
 904
 905 static int rs_read_proc(char *page, char **start, off_t off, int count,
 906                  int *eof, void *data)
 907 {
 908         int i, len = 0, l;
 909         off_t   begin = 0;
 910
 911         len += sprintf(page, "simserinfo:1.0 driver:%s\n", serial_version);
 912         for (i = 0; i < NR_PORTS && len < 4000; i++) {
 913                 l = line_info(page + len, &rs_table[i]);
 914                 len += l;
 915                 if (len+begin > off+count)
 916                         goto done;
 917                 if (len+begin < off) {
 918                         begin += len;
 919                         len = 0;
 920                 }
 921         }
 922         *eof = 1;
 923 done:
 924         if (off >= len+begin)
 925                 return 0;
 926         *start = page + (begin-off);
 927         return ((count < begin+len-off) ? count : begin+len-off);
 928 }
 929
 930 /*
 931  * ---------------------------------------------------------------------
 932  * rs_init() and friends
 933  *
 934  * rs_init() is called at boot-time to initialize the serial driver.
 935  * ---------------------------------------------------------------------
 936  */
 937
 938 /*
 939  * This routine prints out the appropriate serial driver version
 940  * number, and identifies which options were configured into this
 941  * driver.
 942  */
 943 static inline void show_serial_version(void)
 944 {
 945         printk(KERN_INFO "%s version %s with", serial_name, serial_version);
 946         printk(KERN_INFO " no serial options enabled\n");
 947 }
 948
 949 static struct tty_operations hp_ops = {
 950         .open = rs_open,
 951         .close = rs_close,
 952         .write = rs_write,
 953         .put_char = rs_put_char,
 954         .flush_chars = rs_flush_chars,
 955         .write_room = rs_write_room,
 956         .chars_in_buffer = rs_chars_in_buffer,
 957         .flush_buffer = rs_flush_buffer,
 958         .ioctl = rs_ioctl,
 959         .throttle = rs_throttle,
 960         .unthrottle = rs_unthrottle,
 961         .send_xchar = rs_send_xchar,
 962         .set_termios = rs_set_termios,
 963         .stop = rs_stop,
 964         .start = rs_start,
 965         .hangup = rs_hangup,
 966         .break_ctl = rs_break,
 967         .wait_until_sent = rs_wait_until_sent,
 968         .read_proc = rs_read_proc,
 969 };
 970
 971 /*
 972  * The serial driver boot-time initialization code!
 973  */
 974 static int __init
 975 simrs_init (void)
 976 {
 977         int                     i, rc;
 978         struct serial_state     *state;
 979
 980         if (!ia64_platform_is("hpsim"))
 981                 return -ENODEV;
 982
 983         hp_simserial_driver = alloc_tty_driver(1);
 984         if (!hp_simserial_driver)
 985                 return -ENOMEM;
 986
 987         show_serial_version();
 988
 989         /* Initialize the tty_driver structure */
 990
 991         hp_simserial_driver->owner = THIS_MODULE;
 992         hp_simserial_driver->driver_name = "simserial";
 993         hp_simserial_driver->name = "ttyS";
 994         hp_simserial_driver->major = TTY_MAJOR;
 995         hp_simserial_driver->minor_start = 64;
 996         hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
 997         hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
 998         hp_simserial_driver->init_termios = tty_std_termios;
 999         hp_simserial_driver->init_termios.c_cflag =
1000                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1001         hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
1002         tty_set_operations(hp_simserial_driver, &hp_ops);
1003
1004         /*
1005          * Let's have a little bit of fun !
1006          */
1007         for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
1008
1009                 if (state->type == PORT_UNKNOWN) continue;
1010
1011                 if (!state->irq) {
1012                         if ((rc = assign_irq_vector(AUTO_ASSIGN)) < 0)
1013                                 panic("%s: out of interrupt vectors!\n",
1014                                       __FUNCTION__);
1015                         state->irq = rc;
1016                         ia64_ssc_connect_irq(KEYBOARD_INTR, state->irq);
1017                 }
1018
1019                 printk(KERN_INFO "ttyS%d at 0x%04lx (irq = %d) is a %s\n",
1020                        state->line,
1021                        state->port, state->irq,
1022                        uart_config[state->type].name);
1023         }
1024
1025         if (tty_register_driver(hp_simserial_driver))
1026                 panic("Couldn't register simserial driver\n");
1027
1028         return 0;
1029 }
1030
1031 #ifndef MODULE
1032 __initcall(simrs_init);
1033 #endif