Linux-2.6.12-rc2
[linux-2.6.git] / 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,
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                         current->state = TASK_INTERRUPTIBLE;
641                         schedule_timeout(info->close_delay);
642                 }
643                 wake_up_interruptible(&info->open_wait);
644         }
645         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
646         wake_up_interruptible(&info->close_wait);
647 }
648
649 /*
650  * rs_wait_until_sent() --- wait until the transmitter is empty
651  */
652 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
653 {
654 }
655
656
657 /*
658  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
659  */
660 static void rs_hangup(struct tty_struct *tty)
661 {
662         struct async_struct * info = (struct async_struct *)tty->driver_data;
663         struct serial_state *state = info->state;
664
665 #ifdef SIMSERIAL_DEBUG
666         printk("rs_hangup: called\n");
667 #endif
668
669         state = info->state;
670
671         rs_flush_buffer(tty);
672         if (info->flags & ASYNC_CLOSING)
673                 return;
674         shutdown(info);
675
676         info->event = 0;
677         state->count = 0;
678         info->flags &= ~ASYNC_NORMAL_ACTIVE;
679         info->tty = 0;
680         wake_up_interruptible(&info->open_wait);
681 }
682
683
684 static int get_async_struct(int line, struct async_struct **ret_info)
685 {
686         struct async_struct *info;
687         struct serial_state *sstate;
688
689         sstate = rs_table + line;
690         sstate->count++;
691         if (sstate->info) {
692                 *ret_info = sstate->info;
693                 return 0;
694         }
695         info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
696         if (!info) {
697                 sstate->count--;
698                 return -ENOMEM;
699         }
700         memset(info, 0, sizeof(struct async_struct));
701         init_waitqueue_head(&info->open_wait);
702         init_waitqueue_head(&info->close_wait);
703         init_waitqueue_head(&info->delta_msr_wait);
704         info->magic = SERIAL_MAGIC;
705         info->port = sstate->port;
706         info->flags = sstate->flags;
707         info->xmit_fifo_size = sstate->xmit_fifo_size;
708         info->line = line;
709         INIT_WORK(&info->work, do_softint, info);
710         info->state = sstate;
711         if (sstate->info) {
712                 kfree(info);
713                 *ret_info = sstate->info;
714                 return 0;
715         }
716         *ret_info = sstate->info = info;
717         return 0;
718 }
719
720 static int
721 startup(struct async_struct *info)
722 {
723         unsigned long flags;
724         int     retval=0;
725         irqreturn_t (*handler)(int, void *, struct pt_regs *);
726         struct serial_state *state= info->state;
727         unsigned long page;
728
729         page = get_zeroed_page(GFP_KERNEL);
730         if (!page)
731                 return -ENOMEM;
732
733         local_irq_save(flags);
734
735         if (info->flags & ASYNC_INITIALIZED) {
736                 free_page(page);
737                 goto errout;
738         }
739
740         if (!state->port || !state->type) {
741                 if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
742                 free_page(page);
743                 goto errout;
744         }
745         if (info->xmit.buf)
746                 free_page(page);
747         else
748                 info->xmit.buf = (unsigned char *) page;
749
750 #ifdef SIMSERIAL_DEBUG
751         printk("startup: ttys%d (irq %d)...", info->line, state->irq);
752 #endif
753
754         /*
755          * Allocate the IRQ if necessary
756          */
757         if (state->irq && (!IRQ_ports[state->irq] ||
758                           !IRQ_ports[state->irq]->next_port)) {
759                 if (IRQ_ports[state->irq]) {
760                         retval = -EBUSY;
761                         goto errout;
762                 } else
763                         handler = rs_interrupt_single;
764
765                 retval = request_irq(state->irq, handler, IRQ_T(info), "simserial", NULL);
766                 if (retval) {
767                         if (capable(CAP_SYS_ADMIN)) {
768                                 if (info->tty)
769                                         set_bit(TTY_IO_ERROR,
770                                                 &info->tty->flags);
771                                 retval = 0;
772                         }
773                         goto errout;
774                 }
775         }
776
777         /*
778          * Insert serial port into IRQ chain.
779          */
780         info->prev_port = 0;
781         info->next_port = IRQ_ports[state->irq];
782         if (info->next_port)
783                 info->next_port->prev_port = info;
784         IRQ_ports[state->irq] = info;
785
786         if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags);
787
788         info->xmit.head = info->xmit.tail = 0;
789
790 #if 0
791         /*
792          * Set up serial timers...
793          */
794         timer_table[RS_TIMER].expires = jiffies + 2*HZ/100;
795         timer_active |= 1 << RS_TIMER;
796 #endif
797
798         /*
799          * Set up the tty->alt_speed kludge
800          */
801         if (info->tty) {
802                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
803                         info->tty->alt_speed = 57600;
804                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
805                         info->tty->alt_speed = 115200;
806                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
807                         info->tty->alt_speed = 230400;
808                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
809                         info->tty->alt_speed = 460800;
810         }
811
812         info->flags |= ASYNC_INITIALIZED;
813         local_irq_restore(flags);
814         return 0;
815
816 errout:
817         local_irq_restore(flags);
818         return retval;
819 }
820
821
822 /*
823  * This routine is called whenever a serial port is opened.  It
824  * enables interrupts for a serial port, linking in its async structure into
825  * the IRQ chain.   It also performs the serial-specific
826  * initialization for the tty structure.
827  */
828 static int rs_open(struct tty_struct *tty, struct file * filp)
829 {
830         struct async_struct     *info;
831         int                     retval, line;
832         unsigned long           page;
833
834         line = tty->index;
835         if ((line < 0) || (line >= NR_PORTS))
836                 return -ENODEV;
837         retval = get_async_struct(line, &info);
838         if (retval)
839                 return retval;
840         tty->driver_data = info;
841         info->tty = tty;
842
843 #ifdef SIMSERIAL_DEBUG
844         printk("rs_open %s, count = %d\n", tty->name, info->state->count);
845 #endif
846         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
847
848         if (!tmp_buf) {
849                 page = get_zeroed_page(GFP_KERNEL);
850                 if (!page)
851                         return -ENOMEM;
852                 if (tmp_buf)
853                         free_page(page);
854                 else
855                         tmp_buf = (unsigned char *) page;
856         }
857
858         /*
859          * If the port is the middle of closing, bail out now
860          */
861         if (tty_hung_up_p(filp) ||
862             (info->flags & ASYNC_CLOSING)) {
863                 if (info->flags & ASYNC_CLOSING)
864                         interruptible_sleep_on(&info->close_wait);
865 #ifdef SERIAL_DO_RESTART
866                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
867                         -EAGAIN : -ERESTARTSYS);
868 #else
869                 return -EAGAIN;
870 #endif
871         }
872
873         /*
874          * Start up serial port
875          */
876         retval = startup(info);
877         if (retval) {
878                 return retval;
879         }
880
881         /*
882          * figure out which console to use (should be one already)
883          */
884         console = console_drivers;
885         while (console) {
886                 if ((console->flags & CON_ENABLED) && console->write) break;
887                 console = console->next;
888         }
889
890 #ifdef SIMSERIAL_DEBUG
891         printk("rs_open ttys%d successful\n", info->line);
892 #endif
893         return 0;
894 }
895
896 /*
897  * /proc fs routines....
898  */
899
900 static inline int line_info(char *buf, struct serial_state *state)
901 {
902         return sprintf(buf, "%d: uart:%s port:%lX irq:%d\n",
903                        state->line, uart_config[state->type].name,
904                        state->port, state->irq);
905 }
906
907 static int rs_read_proc(char *page, char **start, off_t off, int count,
908                  int *eof, void *data)
909 {
910         int i, len = 0, l;
911         off_t   begin = 0;
912
913         len += sprintf(page, "simserinfo:1.0 driver:%s\n", serial_version);
914         for (i = 0; i < NR_PORTS && len < 4000; i++) {
915                 l = line_info(page + len, &rs_table[i]);
916                 len += l;
917                 if (len+begin > off+count)
918                         goto done;
919                 if (len+begin < off) {
920                         begin += len;
921                         len = 0;
922                 }
923         }
924         *eof = 1;
925 done:
926         if (off >= len+begin)
927                 return 0;
928         *start = page + (begin-off);
929         return ((count < begin+len-off) ? count : begin+len-off);
930 }
931
932 /*
933  * ---------------------------------------------------------------------
934  * rs_init() and friends
935  *
936  * rs_init() is called at boot-time to initialize the serial driver.
937  * ---------------------------------------------------------------------
938  */
939
940 /*
941  * This routine prints out the appropriate serial driver version
942  * number, and identifies which options were configured into this
943  * driver.
944  */
945 static inline void show_serial_version(void)
946 {
947         printk(KERN_INFO "%s version %s with", serial_name, serial_version);
948         printk(KERN_INFO " no serial options enabled\n");
949 }
950
951 static struct tty_operations hp_ops = {
952         .open = rs_open,
953         .close = rs_close,
954         .write = rs_write,
955         .put_char = rs_put_char,
956         .flush_chars = rs_flush_chars,
957         .write_room = rs_write_room,
958         .chars_in_buffer = rs_chars_in_buffer,
959         .flush_buffer = rs_flush_buffer,
960         .ioctl = rs_ioctl,
961         .throttle = rs_throttle,
962         .unthrottle = rs_unthrottle,
963         .send_xchar = rs_send_xchar,
964         .set_termios = rs_set_termios,
965         .stop = rs_stop,
966         .start = rs_start,
967         .hangup = rs_hangup,
968         .break_ctl = rs_break,
969         .wait_until_sent = rs_wait_until_sent,
970         .read_proc = rs_read_proc,
971 };
972
973 /*
974  * The serial driver boot-time initialization code!
975  */
976 static int __init
977 simrs_init (void)
978 {
979         int                     i;
980         struct serial_state     *state;
981
982         if (!ia64_platform_is("hpsim"))
983                 return -ENODEV;
984
985         hp_simserial_driver = alloc_tty_driver(1);
986         if (!hp_simserial_driver)
987                 return -ENOMEM;
988
989         show_serial_version();
990
991         /* Initialize the tty_driver structure */
992
993         hp_simserial_driver->owner = THIS_MODULE;
994         hp_simserial_driver->driver_name = "simserial";
995         hp_simserial_driver->name = "ttyS";
996         hp_simserial_driver->major = TTY_MAJOR;
997         hp_simserial_driver->minor_start = 64;
998         hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
999         hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
1000         hp_simserial_driver->init_termios = tty_std_termios;
1001         hp_simserial_driver->init_termios.c_cflag =
1002                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1003         hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
1004         tty_set_operations(hp_simserial_driver, &hp_ops);
1005
1006         /*
1007          * Let's have a little bit of fun !
1008          */
1009         for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
1010
1011                 if (state->type == PORT_UNKNOWN) continue;
1012
1013                 if (!state->irq) {
1014                         state->irq = assign_irq_vector(AUTO_ASSIGN);
1015                         ia64_ssc_connect_irq(KEYBOARD_INTR, state->irq);
1016                 }
1017
1018                 printk(KERN_INFO "ttyS%d at 0x%04lx (irq = %d) is a %s\n",
1019                        state->line,
1020                        state->port, state->irq,
1021                        uart_config[state->type].name);
1022         }
1023
1024         if (tty_register_driver(hp_simserial_driver))
1025                 panic("Couldn't register simserial driver\n");
1026
1027         return 0;
1028 }
1029
1030 #ifndef MODULE
1031 __initcall(simrs_init);
1032 #endif