Merge branch 'upstream' into upstream-jgarzik
[linux-2.6] / drivers / char / amiserial.c
1 /*
2  *  linux/drivers/char/amiserial.c
3  *
4  * Serial driver for the amiga builtin port.
5  *
6  * This code was created by taking serial.c version 4.30 from kernel
7  * release 2.3.22, replacing all hardware related stuff with the
8  * corresponding amiga hardware actions, and removing all irrelevant
9  * code. As a consequence, it uses many of the constants and names
10  * associated with the registers and bits of 16550 compatible UARTS -
11  * but only to keep track of status, etc in the state variables. It
12  * was done this was to make it easier to keep the code in line with
13  * (non hardware specific) changes to serial.c.
14  *
15  * The port is registered with the tty driver as minor device 64, and
16  * therefore other ports should should only use 65 upwards.
17  *
18  * Richard Lucock 28/12/99
19  *
20  *  Copyright (C) 1991, 1992  Linus Torvalds
21  *  Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 
22  *              1998, 1999  Theodore Ts'o
23  *
24  */
25
26 /*
27  * Serial driver configuration section.  Here are the various options:
28  *
29  * SERIAL_PARANOIA_CHECK
30  *              Check the magic number for the async_structure where
31  *              ever possible.
32  */
33
34 #include <linux/delay.h>
35
36 #undef SERIAL_PARANOIA_CHECK
37 #define SERIAL_DO_RESTART
38
39 /* Set of debugging defines */
40
41 #undef SERIAL_DEBUG_INTR
42 #undef SERIAL_DEBUG_OPEN
43 #undef SERIAL_DEBUG_FLOW
44 #undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
45
46 /* Sanity checks */
47
48 #if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
49 #define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
50  tty->name, (info->flags), serial_driver->refcount,info->count,tty->count,s)
51 #else
52 #define DBG_CNT(s)
53 #endif
54
55 /*
56  * End of serial driver configuration section.
57  */
58
59 #include <linux/module.h>
60
61 #include <linux/types.h>
62 #include <linux/serial.h>
63 #include <linux/serialP.h>
64 #include <linux/serial_reg.h>
65 static char *serial_version = "4.30";
66
67 #include <linux/errno.h>
68 #include <linux/signal.h>
69 #include <linux/sched.h>
70 #include <linux/kernel.h>
71 #include <linux/timer.h>
72 #include <linux/interrupt.h>
73 #include <linux/tty.h>
74 #include <linux/tty_flip.h>
75 #include <linux/console.h>
76 #include <linux/major.h>
77 #include <linux/string.h>
78 #include <linux/fcntl.h>
79 #include <linux/ptrace.h>
80 #include <linux/ioport.h>
81 #include <linux/mm.h>
82 #include <linux/slab.h>
83 #include <linux/init.h>
84 #include <linux/bitops.h>
85
86 #include <asm/setup.h>
87
88 #include <asm/system.h>
89
90 #include <asm/irq.h>
91
92 #include <asm/amigahw.h>
93 #include <asm/amigaints.h>
94
95 #define custom amiga_custom
96 static char *serial_name = "Amiga-builtin serial driver";
97
98 static struct tty_driver *serial_driver;
99
100 /* number of characters left in xmit buffer before we ask for more */
101 #define WAKEUP_CHARS 256
102
103 static struct async_struct *IRQ_ports;
104
105 static unsigned char current_ctl_bits;
106
107 static void change_speed(struct async_struct *info, struct ktermios *old);
108 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
109
110
111 static struct serial_state rs_table[1];
112
113 #define NR_PORTS ARRAY_SIZE(rs_table)
114
115 #include <asm/uaccess.h>
116
117 #define serial_isroot() (capable(CAP_SYS_ADMIN))
118
119
120 static inline int serial_paranoia_check(struct async_struct *info,
121                                         char *name, const char *routine)
122 {
123 #ifdef SERIAL_PARANOIA_CHECK
124         static const char *badmagic =
125                 "Warning: bad magic number for serial struct (%s) in %s\n";
126         static const char *badinfo =
127                 "Warning: null async_struct for (%s) in %s\n";
128
129         if (!info) {
130                 printk(badinfo, name, routine);
131                 return 1;
132         }
133         if (info->magic != SERIAL_MAGIC) {
134                 printk(badmagic, name, routine);
135                 return 1;
136         }
137 #endif
138         return 0;
139 }
140
141 /* some serial hardware definitions */
142 #define SDR_OVRUN   (1<<15)
143 #define SDR_RBF     (1<<14)
144 #define SDR_TBE     (1<<13)
145 #define SDR_TSRE    (1<<12)
146
147 #define SERPER_PARENB    (1<<15)
148
149 #define AC_SETCLR   (1<<15)
150 #define AC_UARTBRK  (1<<11)
151
152 #define SER_DTR     (1<<7)
153 #define SER_RTS     (1<<6)
154 #define SER_DCD     (1<<5)
155 #define SER_CTS     (1<<4)
156 #define SER_DSR     (1<<3)
157
158 static __inline__ void rtsdtr_ctrl(int bits)
159 {
160     ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
161 }
162
163 /*
164  * ------------------------------------------------------------
165  * rs_stop() and rs_start()
166  *
167  * This routines are called before setting or resetting tty->stopped.
168  * They enable or disable transmitter interrupts, as necessary.
169  * ------------------------------------------------------------
170  */
171 static void rs_stop(struct tty_struct *tty)
172 {
173         struct async_struct *info = (struct async_struct *)tty->driver_data;
174         unsigned long flags;
175
176         if (serial_paranoia_check(info, tty->name, "rs_stop"))
177                 return;
178
179         local_irq_save(flags);
180         if (info->IER & UART_IER_THRI) {
181                 info->IER &= ~UART_IER_THRI;
182                 /* disable Tx interrupt and remove any pending interrupts */
183                 custom.intena = IF_TBE;
184                 mb();
185                 custom.intreq = IF_TBE;
186                 mb();
187         }
188         local_irq_restore(flags);
189 }
190
191 static void rs_start(struct tty_struct *tty)
192 {
193         struct async_struct *info = (struct async_struct *)tty->driver_data;
194         unsigned long flags;
195
196         if (serial_paranoia_check(info, tty->name, "rs_start"))
197                 return;
198
199         local_irq_save(flags);
200         if (info->xmit.head != info->xmit.tail
201             && info->xmit.buf
202             && !(info->IER & UART_IER_THRI)) {
203                 info->IER |= UART_IER_THRI;
204                 custom.intena = IF_SETCLR | IF_TBE;
205                 mb();
206                 /* set a pending Tx Interrupt, transmitter should restart now */
207                 custom.intreq = IF_SETCLR | IF_TBE;
208                 mb();
209         }
210         local_irq_restore(flags);
211 }
212
213 /*
214  * ----------------------------------------------------------------------
215  *
216  * Here starts the interrupt handling routines.  All of the following
217  * subroutines are declared as inline and are folded into
218  * rs_interrupt().  They were separated out for readability's sake.
219  *
220  * Note: rs_interrupt() is a "fast" interrupt, which means that it
221  * runs with interrupts turned off.  People who may want to modify
222  * rs_interrupt() should try to keep the interrupt handler as fast as
223  * possible.  After you are done making modifications, it is not a bad
224  * idea to do:
225  * 
226  * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
227  *
228  * and look at the resulting assemble code in serial.s.
229  *
230  *                              - Ted Ts'o (tytso@mit.edu), 7-Mar-93
231  * -----------------------------------------------------------------------
232  */
233
234 /*
235  * This routine is used by the interrupt handler to schedule
236  * processing in the software interrupt portion of the driver.
237  */
238 static void rs_sched_event(struct async_struct *info,
239                            int event)
240 {
241         info->event |= 1 << event;
242         tasklet_schedule(&info->tlet);
243 }
244
245 static void receive_chars(struct async_struct *info)
246 {
247         int status;
248         int serdatr;
249         struct tty_struct *tty = info->tty;
250         unsigned char ch, flag;
251         struct  async_icount *icount;
252         int oe = 0;
253
254         icount = &info->state->icount;
255
256         status = UART_LSR_DR; /* We obviously have a character! */
257         serdatr = custom.serdatr;
258         mb();
259         custom.intreq = IF_RBF;
260         mb();
261
262         if((serdatr & 0x1ff) == 0)
263             status |= UART_LSR_BI;
264         if(serdatr & SDR_OVRUN)
265             status |= UART_LSR_OE;
266
267         ch = serdatr & 0xff;
268         icount->rx++;
269
270 #ifdef SERIAL_DEBUG_INTR
271         printk("DR%02x:%02x...", ch, status);
272 #endif
273         flag = TTY_NORMAL;
274
275         /*
276          * We don't handle parity or frame errors - but I have left
277          * the code in, since I'm not sure that the errors can't be
278          * detected.
279          */
280
281         if (status & (UART_LSR_BI | UART_LSR_PE |
282                       UART_LSR_FE | UART_LSR_OE)) {
283           /*
284            * For statistics only
285            */
286           if (status & UART_LSR_BI) {
287             status &= ~(UART_LSR_FE | UART_LSR_PE);
288             icount->brk++;
289           } else if (status & UART_LSR_PE)
290             icount->parity++;
291           else if (status & UART_LSR_FE)
292             icount->frame++;
293           if (status & UART_LSR_OE)
294             icount->overrun++;
295
296           /*
297            * Now check to see if character should be
298            * ignored, and mask off conditions which
299            * should be ignored.
300            */
301           if (status & info->ignore_status_mask)
302             goto out;
303
304           status &= info->read_status_mask;
305
306           if (status & (UART_LSR_BI)) {
307 #ifdef SERIAL_DEBUG_INTR
308             printk("handling break....");
309 #endif
310             flag = TTY_BREAK;
311             if (info->flags & ASYNC_SAK)
312               do_SAK(tty);
313           } else if (status & UART_LSR_PE)
314             flag = TTY_PARITY;
315           else if (status & UART_LSR_FE)
316             flag = TTY_FRAME;
317           if (status & UART_LSR_OE) {
318             /*
319              * Overrun is special, since it's
320              * reported immediately, and doesn't
321              * affect the current character
322              */
323              oe = 1;
324           }
325         }
326         tty_insert_flip_char(tty, ch, flag);
327         if (oe == 1)
328                 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
329         tty_flip_buffer_push(tty);
330 out:
331         return;
332 }
333
334 static void transmit_chars(struct async_struct *info)
335 {
336         custom.intreq = IF_TBE;
337         mb();
338         if (info->x_char) {
339                 custom.serdat = info->x_char | 0x100;
340                 mb();
341                 info->state->icount.tx++;
342                 info->x_char = 0;
343                 return;
344         }
345         if (info->xmit.head == info->xmit.tail
346             || info->tty->stopped
347             || info->tty->hw_stopped) {
348                 info->IER &= ~UART_IER_THRI;
349                 custom.intena = IF_TBE;
350                 mb();
351                 return;
352         }
353
354         custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
355         mb();
356         info->xmit.tail = info->xmit.tail & (SERIAL_XMIT_SIZE-1);
357         info->state->icount.tx++;
358
359         if (CIRC_CNT(info->xmit.head,
360                      info->xmit.tail,
361                      SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
362                 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
363
364 #ifdef SERIAL_DEBUG_INTR
365         printk("THRE...");
366 #endif
367         if (info->xmit.head == info->xmit.tail) {
368                 custom.intena = IF_TBE;
369                 mb();
370                 info->IER &= ~UART_IER_THRI;
371         }
372 }
373
374 static void check_modem_status(struct async_struct *info)
375 {
376         unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
377         unsigned char dstatus;
378         struct  async_icount *icount;
379
380         /* Determine bits that have changed */
381         dstatus = status ^ current_ctl_bits;
382         current_ctl_bits = status;
383
384         if (dstatus) {
385                 icount = &info->state->icount;
386                 /* update input line counters */
387                 if (dstatus & SER_DSR)
388                         icount->dsr++;
389                 if (dstatus & SER_DCD) {
390                         icount->dcd++;
391 #ifdef CONFIG_HARD_PPS
392                         if ((info->flags & ASYNC_HARDPPS_CD) &&
393                             !(status & SER_DCD))
394                                 hardpps();
395 #endif
396                 }
397                 if (dstatus & SER_CTS)
398                         icount->cts++;
399                 wake_up_interruptible(&info->delta_msr_wait);
400         }
401
402         if ((info->flags & ASYNC_CHECK_CD) && (dstatus & SER_DCD)) {
403 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
404                 printk("ttyS%d CD now %s...", info->line,
405                        (!(status & SER_DCD)) ? "on" : "off");
406 #endif
407                 if (!(status & SER_DCD))
408                         wake_up_interruptible(&info->open_wait);
409                 else {
410 #ifdef SERIAL_DEBUG_OPEN
411                         printk("doing serial hangup...");
412 #endif
413                         if (info->tty)
414                                 tty_hangup(info->tty);
415                 }
416         }
417         if (info->flags & ASYNC_CTS_FLOW) {
418                 if (info->tty->hw_stopped) {
419                         if (!(status & SER_CTS)) {
420 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
421                                 printk("CTS tx start...");
422 #endif
423                                 info->tty->hw_stopped = 0;
424                                 info->IER |= UART_IER_THRI;
425                                 custom.intena = IF_SETCLR | IF_TBE;
426                                 mb();
427                                 /* set a pending Tx Interrupt, transmitter should restart now */
428                                 custom.intreq = IF_SETCLR | IF_TBE;
429                                 mb();
430                                 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
431                                 return;
432                         }
433                 } else {
434                         if ((status & SER_CTS)) {
435 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
436                                 printk("CTS tx stop...");
437 #endif
438                                 info->tty->hw_stopped = 1;
439                                 info->IER &= ~UART_IER_THRI;
440                                 /* disable Tx interrupt and remove any pending interrupts */
441                                 custom.intena = IF_TBE;
442                                 mb();
443                                 custom.intreq = IF_TBE;
444                                 mb();
445                         }
446                 }
447         }
448 }
449
450 static irqreturn_t ser_vbl_int( int irq, void *data)
451 {
452         /* vbl is just a periodic interrupt we tie into to update modem status */
453         struct async_struct * info = IRQ_ports;
454         /*
455          * TBD - is it better to unregister from this interrupt or to
456          * ignore it if MSI is clear ?
457          */
458         if(info->IER & UART_IER_MSI)
459           check_modem_status(info);
460         return IRQ_HANDLED;
461 }
462
463 static irqreturn_t ser_rx_int(int irq, void *dev_id)
464 {
465         struct async_struct * info;
466
467 #ifdef SERIAL_DEBUG_INTR
468         printk("ser_rx_int...");
469 #endif
470
471         info = IRQ_ports;
472         if (!info || !info->tty)
473                 return IRQ_NONE;
474
475         receive_chars(info);
476         info->last_active = jiffies;
477 #ifdef SERIAL_DEBUG_INTR
478         printk("end.\n");
479 #endif
480         return IRQ_HANDLED;
481 }
482
483 static irqreturn_t ser_tx_int(int irq, void *dev_id)
484 {
485         struct async_struct * info;
486
487         if (custom.serdatr & SDR_TBE) {
488 #ifdef SERIAL_DEBUG_INTR
489           printk("ser_tx_int...");
490 #endif
491
492           info = IRQ_ports;
493           if (!info || !info->tty)
494                 return IRQ_NONE;
495
496           transmit_chars(info);
497           info->last_active = jiffies;
498 #ifdef SERIAL_DEBUG_INTR
499           printk("end.\n");
500 #endif
501         }
502         return IRQ_HANDLED;
503 }
504
505 /*
506  * -------------------------------------------------------------------
507  * Here ends the serial interrupt routines.
508  * -------------------------------------------------------------------
509  */
510
511 /*
512  * This routine is used to handle the "bottom half" processing for the
513  * serial driver, known also the "software interrupt" processing.
514  * This processing is done at the kernel interrupt level, after the
515  * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
516  * is where time-consuming activities which can not be done in the
517  * interrupt driver proper are done; the interrupt driver schedules
518  * them using rs_sched_event(), and they get done here.
519  */
520
521 static void do_softint(unsigned long private_)
522 {
523         struct async_struct     *info = (struct async_struct *) private_;
524         struct tty_struct       *tty;
525
526         tty = info->tty;
527         if (!tty)
528                 return;
529
530         if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event))
531                 tty_wakeup(tty);
532 }
533
534 /*
535  * ---------------------------------------------------------------
536  * Low level utility subroutines for the serial driver:  routines to
537  * figure out the appropriate timeout for an interrupt chain, routines
538  * to initialize and startup a serial port, and routines to shutdown a
539  * serial port.  Useful stuff like that.
540  * ---------------------------------------------------------------
541  */
542
543 static int startup(struct async_struct * info)
544 {
545         unsigned long flags;
546         int     retval=0;
547         unsigned long page;
548
549         page = get_zeroed_page(GFP_KERNEL);
550         if (!page)
551                 return -ENOMEM;
552
553         local_irq_save(flags);
554
555         if (info->flags & ASYNC_INITIALIZED) {
556                 free_page(page);
557                 goto errout;
558         }
559
560         if (info->xmit.buf)
561                 free_page(page);
562         else
563                 info->xmit.buf = (unsigned char *) page;
564
565 #ifdef SERIAL_DEBUG_OPEN
566         printk("starting up ttys%d ...", info->line);
567 #endif
568
569         /* Clear anything in the input buffer */
570
571         custom.intreq = IF_RBF;
572         mb();
573
574         retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
575         if (retval) {
576           if (serial_isroot()) {
577             if (info->tty)
578               set_bit(TTY_IO_ERROR,
579                       &info->tty->flags);
580             retval = 0;
581           }
582           goto errout;
583         }
584
585         /* enable both Rx and Tx interrupts */
586         custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
587         mb();
588         info->IER = UART_IER_MSI;
589
590         /* remember current state of the DCD and CTS bits */
591         current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
592
593         IRQ_ports = info;
594
595         info->MCR = 0;
596         if (info->tty->termios->c_cflag & CBAUD)
597           info->MCR = SER_DTR | SER_RTS;
598         rtsdtr_ctrl(info->MCR);
599
600         if (info->tty)
601                 clear_bit(TTY_IO_ERROR, &info->tty->flags);
602         info->xmit.head = info->xmit.tail = 0;
603
604         /*
605          * Set up the tty->alt_speed kludge
606          */
607         if (info->tty) {
608                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
609                         info->tty->alt_speed = 57600;
610                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
611                         info->tty->alt_speed = 115200;
612                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
613                         info->tty->alt_speed = 230400;
614                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
615                         info->tty->alt_speed = 460800;
616         }
617
618         /*
619          * and set the speed of the serial port
620          */
621         change_speed(info, NULL);
622
623         info->flags |= ASYNC_INITIALIZED;
624         local_irq_restore(flags);
625         return 0;
626
627 errout:
628         local_irq_restore(flags);
629         return retval;
630 }
631
632 /*
633  * This routine will shutdown a serial port; interrupts are disabled, and
634  * DTR is dropped if the hangup on close termio flag is on.
635  */
636 static void shutdown(struct async_struct * info)
637 {
638         unsigned long   flags;
639         struct serial_state *state;
640
641         if (!(info->flags & ASYNC_INITIALIZED))
642                 return;
643
644         state = info->state;
645
646 #ifdef SERIAL_DEBUG_OPEN
647         printk("Shutting down serial port %d ....\n", info->line);
648 #endif
649
650         local_irq_save(flags); /* Disable interrupts */
651
652         /*
653          * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
654          * here so the queue might never be waken up
655          */
656         wake_up_interruptible(&info->delta_msr_wait);
657
658         IRQ_ports = NULL;
659
660         /*
661          * Free the IRQ, if necessary
662          */
663         free_irq(IRQ_AMIGA_VERTB, info);
664
665         if (info->xmit.buf) {
666                 free_page((unsigned long) info->xmit.buf);
667                 info->xmit.buf = NULL;
668         }
669
670         info->IER = 0;
671         custom.intena = IF_RBF | IF_TBE;
672         mb();
673
674         /* disable break condition */
675         custom.adkcon = AC_UARTBRK;
676         mb();
677
678         if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
679                 info->MCR &= ~(SER_DTR|SER_RTS);
680         rtsdtr_ctrl(info->MCR);
681
682         if (info->tty)
683                 set_bit(TTY_IO_ERROR, &info->tty->flags);
684
685         info->flags &= ~ASYNC_INITIALIZED;
686         local_irq_restore(flags);
687 }
688
689
690 /*
691  * This routine is called to set the UART divisor registers to match
692  * the specified baud rate for a serial port.
693  */
694 static void change_speed(struct async_struct *info,
695                          struct ktermios *old_termios)
696 {
697         int     quot = 0, baud_base, baud;
698         unsigned cflag, cval = 0;
699         int     bits;
700         unsigned long   flags;
701
702         if (!info->tty || !info->tty->termios)
703                 return;
704         cflag = info->tty->termios->c_cflag;
705
706         /* Byte size is always 8 bits plus parity bit if requested */
707
708         cval = 3; bits = 10;
709         if (cflag & CSTOPB) {
710                 cval |= 0x04;
711                 bits++;
712         }
713         if (cflag & PARENB) {
714                 cval |= UART_LCR_PARITY;
715                 bits++;
716         }
717         if (!(cflag & PARODD))
718                 cval |= UART_LCR_EPAR;
719 #ifdef CMSPAR
720         if (cflag & CMSPAR)
721                 cval |= UART_LCR_SPAR;
722 #endif
723
724         /* Determine divisor based on baud rate */
725         baud = tty_get_baud_rate(info->tty);
726         if (!baud)
727                 baud = 9600;    /* B0 transition handled in rs_set_termios */
728         baud_base = info->state->baud_base;
729         if (baud == 38400 &&
730             ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
731                 quot = info->state->custom_divisor;
732         else {
733                 if (baud == 134)
734                         /* Special case since 134 is really 134.5 */
735                         quot = (2*baud_base / 269);
736                 else if (baud)
737                         quot = baud_base / baud;
738         }
739         /* If the quotient is zero refuse the change */
740         if (!quot && old_termios) {
741                 info->tty->termios->c_cflag &= ~CBAUD;
742                 info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
743                 baud = tty_get_baud_rate(info->tty);
744                 if (!baud)
745                         baud = 9600;
746                 if (baud == 38400 &&
747                     ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
748                         quot = info->state->custom_divisor;
749                 else {
750                         if (baud == 134)
751                                 /* Special case since 134 is really 134.5 */
752                                 quot = (2*baud_base / 269);
753                         else if (baud)
754                                 quot = baud_base / baud;
755                 }
756         }
757         /* As a last resort, if the quotient is zero, default to 9600 bps */
758         if (!quot)
759                 quot = baud_base / 9600;
760         info->quot = quot;
761         info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
762         info->timeout += HZ/50;         /* Add .02 seconds of slop */
763
764         /* CTS flow control flag and modem status interrupts */
765         info->IER &= ~UART_IER_MSI;
766         if (info->flags & ASYNC_HARDPPS_CD)
767                 info->IER |= UART_IER_MSI;
768         if (cflag & CRTSCTS) {
769                 info->flags |= ASYNC_CTS_FLOW;
770                 info->IER |= UART_IER_MSI;
771         } else
772                 info->flags &= ~ASYNC_CTS_FLOW;
773         if (cflag & CLOCAL)
774                 info->flags &= ~ASYNC_CHECK_CD;
775         else {
776                 info->flags |= ASYNC_CHECK_CD;
777                 info->IER |= UART_IER_MSI;
778         }
779         /* TBD:
780          * Does clearing IER_MSI imply that we should disbale the VBL interrupt ?
781          */
782
783         /*
784          * Set up parity check flag
785          */
786 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
787
788         info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
789         if (I_INPCK(info->tty))
790                 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
791         if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
792                 info->read_status_mask |= UART_LSR_BI;
793
794         /*
795          * Characters to ignore
796          */
797         info->ignore_status_mask = 0;
798         if (I_IGNPAR(info->tty))
799                 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
800         if (I_IGNBRK(info->tty)) {
801                 info->ignore_status_mask |= UART_LSR_BI;
802                 /*
803                  * If we're ignore parity and break indicators, ignore 
804                  * overruns too.  (For real raw support).
805                  */
806                 if (I_IGNPAR(info->tty))
807                         info->ignore_status_mask |= UART_LSR_OE;
808         }
809         /*
810          * !!! ignore all characters if CREAD is not set
811          */
812         if ((cflag & CREAD) == 0)
813                 info->ignore_status_mask |= UART_LSR_DR;
814         local_irq_save(flags);
815
816         {
817           short serper;
818
819         /* Set up the baud rate */
820           serper = quot - 1;
821
822         /* Enable or disable parity bit */
823
824         if(cval & UART_LCR_PARITY)
825           serper |= (SERPER_PARENB);
826
827         custom.serper = serper;
828         mb();
829         }
830
831         info->LCR = cval;                               /* Save LCR */
832         local_irq_restore(flags);
833 }
834
835 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
836 {
837         struct async_struct *info;
838         unsigned long flags;
839
840         if (!tty)
841                 return;
842
843         info = tty->driver_data;
844
845         if (serial_paranoia_check(info, tty->name, "rs_put_char"))
846                 return;
847
848         if (!info->xmit.buf)
849                 return;
850
851         local_irq_save(flags);
852         if (CIRC_SPACE(info->xmit.head,
853                        info->xmit.tail,
854                        SERIAL_XMIT_SIZE) == 0) {
855                 local_irq_restore(flags);
856                 return;
857         }
858
859         info->xmit.buf[info->xmit.head++] = ch;
860         info->xmit.head &= SERIAL_XMIT_SIZE-1;
861         local_irq_restore(flags);
862 }
863
864 static void rs_flush_chars(struct tty_struct *tty)
865 {
866         struct async_struct *info = (struct async_struct *)tty->driver_data;
867         unsigned long flags;
868
869         if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
870                 return;
871
872         if (info->xmit.head == info->xmit.tail
873             || tty->stopped
874             || tty->hw_stopped
875             || !info->xmit.buf)
876                 return;
877
878         local_irq_save(flags);
879         info->IER |= UART_IER_THRI;
880         custom.intena = IF_SETCLR | IF_TBE;
881         mb();
882         /* set a pending Tx Interrupt, transmitter should restart now */
883         custom.intreq = IF_SETCLR | IF_TBE;
884         mb();
885         local_irq_restore(flags);
886 }
887
888 static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
889 {
890         int     c, ret = 0;
891         struct async_struct *info;
892         unsigned long flags;
893
894         if (!tty)
895                 return 0;
896
897         info = tty->driver_data;
898
899         if (serial_paranoia_check(info, tty->name, "rs_write"))
900                 return 0;
901
902         if (!info->xmit.buf)
903                 return 0;
904
905         local_irq_save(flags);
906         while (1) {
907                 c = CIRC_SPACE_TO_END(info->xmit.head,
908                                       info->xmit.tail,
909                                       SERIAL_XMIT_SIZE);
910                 if (count < c)
911                         c = count;
912                 if (c <= 0) {
913                         break;
914                 }
915                 memcpy(info->xmit.buf + info->xmit.head, buf, c);
916                 info->xmit.head = ((info->xmit.head + c) &
917                                    (SERIAL_XMIT_SIZE-1));
918                 buf += c;
919                 count -= c;
920                 ret += c;
921         }
922         local_irq_restore(flags);
923
924         if (info->xmit.head != info->xmit.tail
925             && !tty->stopped
926             && !tty->hw_stopped
927             && !(info->IER & UART_IER_THRI)) {
928                 info->IER |= UART_IER_THRI;
929                 local_irq_disable();
930                 custom.intena = IF_SETCLR | IF_TBE;
931                 mb();
932                 /* set a pending Tx Interrupt, transmitter should restart now */
933                 custom.intreq = IF_SETCLR | IF_TBE;
934                 mb();
935                 local_irq_restore(flags);
936         }
937         return ret;
938 }
939
940 static int rs_write_room(struct tty_struct *tty)
941 {
942         struct async_struct *info = (struct async_struct *)tty->driver_data;
943
944         if (serial_paranoia_check(info, tty->name, "rs_write_room"))
945                 return 0;
946         return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
947 }
948
949 static int rs_chars_in_buffer(struct tty_struct *tty)
950 {
951         struct async_struct *info = (struct async_struct *)tty->driver_data;
952
953         if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
954                 return 0;
955         return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
956 }
957
958 static void rs_flush_buffer(struct tty_struct *tty)
959 {
960         struct async_struct *info = (struct async_struct *)tty->driver_data;
961         unsigned long flags;
962
963         if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
964                 return;
965         local_irq_save(flags);
966         info->xmit.head = info->xmit.tail = 0;
967         local_irq_restore(flags);
968         tty_wakeup(tty);
969 }
970
971 /*
972  * This function is used to send a high-priority XON/XOFF character to
973  * the device
974  */
975 static void rs_send_xchar(struct tty_struct *tty, char ch)
976 {
977         struct async_struct *info = (struct async_struct *)tty->driver_data;
978         unsigned long flags;
979
980         if (serial_paranoia_check(info, tty->name, "rs_send_char"))
981                 return;
982
983         info->x_char = ch;
984         if (ch) {
985                 /* Make sure transmit interrupts are on */
986
987                 /* Check this ! */
988                 local_irq_save(flags);
989                 if(!(custom.intenar & IF_TBE)) {
990                     custom.intena = IF_SETCLR | IF_TBE;
991                     mb();
992                     /* set a pending Tx Interrupt, transmitter should restart now */
993                     custom.intreq = IF_SETCLR | IF_TBE;
994                     mb();
995                 }
996                 local_irq_restore(flags);
997
998                 info->IER |= UART_IER_THRI;
999         }
1000 }
1001
1002 /*
1003  * ------------------------------------------------------------
1004  * rs_throttle()
1005  * 
1006  * This routine is called by the upper-layer tty layer to signal that
1007  * incoming characters should be throttled.
1008  * ------------------------------------------------------------
1009  */
1010 static void rs_throttle(struct tty_struct * tty)
1011 {
1012         struct async_struct *info = (struct async_struct *)tty->driver_data;
1013         unsigned long flags;
1014 #ifdef SERIAL_DEBUG_THROTTLE
1015         char    buf[64];
1016
1017         printk("throttle %s: %d....\n", tty_name(tty, buf),
1018                tty->ldisc.chars_in_buffer(tty));
1019 #endif
1020
1021         if (serial_paranoia_check(info, tty->name, "rs_throttle"))
1022                 return;
1023
1024         if (I_IXOFF(tty))
1025                 rs_send_xchar(tty, STOP_CHAR(tty));
1026
1027         if (tty->termios->c_cflag & CRTSCTS)
1028                 info->MCR &= ~SER_RTS;
1029
1030         local_irq_save(flags);
1031         rtsdtr_ctrl(info->MCR);
1032         local_irq_restore(flags);
1033 }
1034
1035 static void rs_unthrottle(struct tty_struct * tty)
1036 {
1037         struct async_struct *info = (struct async_struct *)tty->driver_data;
1038         unsigned long flags;
1039 #ifdef SERIAL_DEBUG_THROTTLE
1040         char    buf[64];
1041
1042         printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1043                tty->ldisc.chars_in_buffer(tty));
1044 #endif
1045
1046         if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1047                 return;
1048
1049         if (I_IXOFF(tty)) {
1050                 if (info->x_char)
1051                         info->x_char = 0;
1052                 else
1053                         rs_send_xchar(tty, START_CHAR(tty));
1054         }
1055         if (tty->termios->c_cflag & CRTSCTS)
1056                 info->MCR |= SER_RTS;
1057         local_irq_save(flags);
1058         rtsdtr_ctrl(info->MCR);
1059         local_irq_restore(flags);
1060 }
1061
1062 /*
1063  * ------------------------------------------------------------
1064  * rs_ioctl() and friends
1065  * ------------------------------------------------------------
1066  */
1067
1068 static int get_serial_info(struct async_struct * info,
1069                            struct serial_struct __user * retinfo)
1070 {
1071         struct serial_struct tmp;
1072         struct serial_state *state = info->state;
1073    
1074         if (!retinfo)
1075                 return -EFAULT;
1076         memset(&tmp, 0, sizeof(tmp));
1077         tmp.type = state->type;
1078         tmp.line = state->line;
1079         tmp.port = state->port;
1080         tmp.irq = state->irq;
1081         tmp.flags = state->flags;
1082         tmp.xmit_fifo_size = state->xmit_fifo_size;
1083         tmp.baud_base = state->baud_base;
1084         tmp.close_delay = state->close_delay;
1085         tmp.closing_wait = state->closing_wait;
1086         tmp.custom_divisor = state->custom_divisor;
1087         if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1088                 return -EFAULT;
1089         return 0;
1090 }
1091
1092 static int set_serial_info(struct async_struct * info,
1093                            struct serial_struct __user * new_info)
1094 {
1095         struct serial_struct new_serial;
1096         struct serial_state old_state, *state;
1097         unsigned int            change_irq,change_port;
1098         int                     retval = 0;
1099
1100         if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1101                 return -EFAULT;
1102         state = info->state;
1103         old_state = *state;
1104   
1105         change_irq = new_serial.irq != state->irq;
1106         change_port = (new_serial.port != state->port);
1107         if(change_irq || change_port || (new_serial.xmit_fifo_size != state->xmit_fifo_size))
1108           return -EINVAL;
1109   
1110         if (!serial_isroot()) {
1111                 if ((new_serial.baud_base != state->baud_base) ||
1112                     (new_serial.close_delay != state->close_delay) ||
1113                     (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
1114                     ((new_serial.flags & ~ASYNC_USR_MASK) !=
1115                      (state->flags & ~ASYNC_USR_MASK)))
1116                         return -EPERM;
1117                 state->flags = ((state->flags & ~ASYNC_USR_MASK) |
1118                                (new_serial.flags & ASYNC_USR_MASK));
1119                 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
1120                                (new_serial.flags & ASYNC_USR_MASK));
1121                 state->custom_divisor = new_serial.custom_divisor;
1122                 goto check_and_exit;
1123         }
1124
1125         if (new_serial.baud_base < 9600)
1126                 return -EINVAL;
1127
1128         /*
1129          * OK, past this point, all the error checking has been done.
1130          * At this point, we start making changes.....
1131          */
1132
1133         state->baud_base = new_serial.baud_base;
1134         state->flags = ((state->flags & ~ASYNC_FLAGS) |
1135                         (new_serial.flags & ASYNC_FLAGS));
1136         info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) |
1137                        (info->flags & ASYNC_INTERNAL_FLAGS));
1138         state->custom_divisor = new_serial.custom_divisor;
1139         state->close_delay = new_serial.close_delay * HZ/100;
1140         state->closing_wait = new_serial.closing_wait * HZ/100;
1141         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1142
1143 check_and_exit:
1144         if (info->flags & ASYNC_INITIALIZED) {
1145                 if (((old_state.flags & ASYNC_SPD_MASK) !=
1146                      (state->flags & ASYNC_SPD_MASK)) ||
1147                     (old_state.custom_divisor != state->custom_divisor)) {
1148                         if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1149                                 info->tty->alt_speed = 57600;
1150                         if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1151                                 info->tty->alt_speed = 115200;
1152                         if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1153                                 info->tty->alt_speed = 230400;
1154                         if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1155                                 info->tty->alt_speed = 460800;
1156                         change_speed(info, NULL);
1157                 }
1158         } else
1159                 retval = startup(info);
1160         return retval;
1161 }
1162
1163
1164 /*
1165  * get_lsr_info - get line status register info
1166  *
1167  * Purpose: Let user call ioctl() to get info when the UART physically
1168  *          is emptied.  On bus types like RS485, the transmitter must
1169  *          release the bus after transmitting. This must be done when
1170  *          the transmit shift register is empty, not be done when the
1171  *          transmit holding register is empty.  This functionality
1172  *          allows an RS485 driver to be written in user space. 
1173  */
1174 static int get_lsr_info(struct async_struct * info, unsigned int __user *value)
1175 {
1176         unsigned char status;
1177         unsigned int result;
1178         unsigned long flags;
1179
1180         local_irq_save(flags);
1181         status = custom.serdatr;
1182         mb();
1183         local_irq_restore(flags);
1184         result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
1185         if (copy_to_user(value, &result, sizeof(int)))
1186                 return -EFAULT;
1187         return 0;
1188 }
1189
1190
1191 static int rs_tiocmget(struct tty_struct *tty, struct file *file)
1192 {
1193         struct async_struct * info = (struct async_struct *)tty->driver_data;
1194         unsigned char control, status;
1195         unsigned long flags;
1196
1197         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1198                 return -ENODEV;
1199         if (tty->flags & (1 << TTY_IO_ERROR))
1200                 return -EIO;
1201
1202         control = info->MCR;
1203         local_irq_save(flags);
1204         status = ciab.pra;
1205         local_irq_restore(flags);
1206         return    ((control & SER_RTS) ? TIOCM_RTS : 0)
1207                 | ((control & SER_DTR) ? TIOCM_DTR : 0)
1208                 | (!(status  & SER_DCD) ? TIOCM_CAR : 0)
1209                 | (!(status  & SER_DSR) ? TIOCM_DSR : 0)
1210                 | (!(status  & SER_CTS) ? TIOCM_CTS : 0);
1211 }
1212
1213 static int rs_tiocmset(struct tty_struct *tty, struct file *file,
1214                        unsigned int set, unsigned int clear)
1215 {
1216         struct async_struct * info = (struct async_struct *)tty->driver_data;
1217         unsigned long flags;
1218
1219         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1220                 return -ENODEV;
1221         if (tty->flags & (1 << TTY_IO_ERROR))
1222                 return -EIO;
1223
1224         local_irq_save(flags);
1225         if (set & TIOCM_RTS)
1226                 info->MCR |= SER_RTS;
1227         if (set & TIOCM_DTR)
1228                 info->MCR |= SER_DTR;
1229         if (clear & TIOCM_RTS)
1230                 info->MCR &= ~SER_RTS;
1231         if (clear & TIOCM_DTR)
1232                 info->MCR &= ~SER_DTR;
1233         rtsdtr_ctrl(info->MCR);
1234         local_irq_restore(flags);
1235         return 0;
1236 }
1237
1238 /*
1239  * rs_break() --- routine which turns the break handling on or off
1240  */
1241 static void rs_break(struct tty_struct *tty, int break_state)
1242 {
1243         struct async_struct * info = (struct async_struct *)tty->driver_data;
1244         unsigned long flags;
1245
1246         if (serial_paranoia_check(info, tty->name, "rs_break"))
1247                 return;
1248
1249         local_irq_save(flags);
1250         if (break_state == -1)
1251           custom.adkcon = AC_SETCLR | AC_UARTBRK;
1252         else
1253           custom.adkcon = AC_UARTBRK;
1254         mb();
1255         local_irq_restore(flags);
1256 }
1257
1258
1259 static int rs_ioctl(struct tty_struct *tty, struct file * file,
1260                     unsigned int cmd, unsigned long arg)
1261 {
1262         struct async_struct * info = (struct async_struct *)tty->driver_data;
1263         struct async_icount cprev, cnow;        /* kernel counter temps */
1264         struct serial_icounter_struct icount;
1265         void __user *argp = (void __user *)arg;
1266         unsigned long flags;
1267
1268         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1269                 return -ENODEV;
1270
1271         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1272             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
1273             (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1274                 if (tty->flags & (1 << TTY_IO_ERROR))
1275                     return -EIO;
1276         }
1277
1278         switch (cmd) {
1279                 case TIOCGSERIAL:
1280                         return get_serial_info(info, argp);
1281                 case TIOCSSERIAL:
1282                         return set_serial_info(info, argp);
1283                 case TIOCSERCONFIG:
1284                         return 0;
1285
1286                 case TIOCSERGETLSR: /* Get line status register */
1287                         return get_lsr_info(info, argp);
1288
1289                 case TIOCSERGSTRUCT:
1290                         if (copy_to_user(argp,
1291                                          info, sizeof(struct async_struct)))
1292                                 return -EFAULT;
1293                         return 0;
1294
1295                 /*
1296                  * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1297                  * - mask passed in arg for lines of interest
1298                  *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1299                  * Caller should use TIOCGICOUNT to see which one it was
1300                  */
1301                 case TIOCMIWAIT:
1302                         local_irq_save(flags);
1303                         /* note the counters on entry */
1304                         cprev = info->state->icount;
1305                         local_irq_restore(flags);
1306                         while (1) {
1307                                 interruptible_sleep_on(&info->delta_msr_wait);
1308                                 /* see if a signal did it */
1309                                 if (signal_pending(current))
1310                                         return -ERESTARTSYS;
1311                                 local_irq_save(flags);
1312                                 cnow = info->state->icount; /* atomic copy */
1313                                 local_irq_restore(flags);
1314                                 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && 
1315                                     cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1316                                         return -EIO; /* no change => error */
1317                                 if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1318                                      ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1319                                      ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
1320                                      ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1321                                         return 0;
1322                                 }
1323                                 cprev = cnow;
1324                         }
1325                         /* NOTREACHED */
1326
1327                 /* 
1328                  * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1329                  * Return: write counters to the user passed counter struct
1330                  * NB: both 1->0 and 0->1 transitions are counted except for
1331                  *     RI where only 0->1 is counted.
1332                  */
1333                 case TIOCGICOUNT:
1334                         local_irq_save(flags);
1335                         cnow = info->state->icount;
1336                         local_irq_restore(flags);
1337                         icount.cts = cnow.cts;
1338                         icount.dsr = cnow.dsr;
1339                         icount.rng = cnow.rng;
1340                         icount.dcd = cnow.dcd;
1341                         icount.rx = cnow.rx;
1342                         icount.tx = cnow.tx;
1343                         icount.frame = cnow.frame;
1344                         icount.overrun = cnow.overrun;
1345                         icount.parity = cnow.parity;
1346                         icount.brk = cnow.brk;
1347                         icount.buf_overrun = cnow.buf_overrun;
1348
1349                         if (copy_to_user(argp, &icount, sizeof(icount)))
1350                                 return -EFAULT;
1351                         return 0;
1352                 case TIOCSERGWILD:
1353                 case TIOCSERSWILD:
1354                         /* "setserial -W" is called in Debian boot */
1355                         printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
1356                         return 0;
1357
1358                 default:
1359                         return -ENOIOCTLCMD;
1360                 }
1361         return 0;
1362 }
1363
1364 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
1365 {
1366         struct async_struct *info = (struct async_struct *)tty->driver_data;
1367         unsigned long flags;
1368         unsigned int cflag = tty->termios->c_cflag;
1369
1370         if (   (cflag == old_termios->c_cflag)
1371             && (   RELEVANT_IFLAG(tty->termios->c_iflag) 
1372                 == RELEVANT_IFLAG(old_termios->c_iflag)))
1373           return;
1374
1375         change_speed(info, old_termios);
1376
1377         /* Handle transition to B0 status */
1378         if ((old_termios->c_cflag & CBAUD) &&
1379             !(cflag & CBAUD)) {
1380                 info->MCR &= ~(SER_DTR|SER_RTS);
1381                 local_irq_save(flags);
1382                 rtsdtr_ctrl(info->MCR);
1383                 local_irq_restore(flags);
1384         }
1385
1386         /* Handle transition away from B0 status */
1387         if (!(old_termios->c_cflag & CBAUD) &&
1388             (cflag & CBAUD)) {
1389                 info->MCR |= SER_DTR;
1390                 if (!(tty->termios->c_cflag & CRTSCTS) || 
1391                     !test_bit(TTY_THROTTLED, &tty->flags)) {
1392                         info->MCR |= SER_RTS;
1393                 }
1394                 local_irq_save(flags);
1395                 rtsdtr_ctrl(info->MCR);
1396                 local_irq_restore(flags);
1397         }
1398
1399         /* Handle turning off CRTSCTS */
1400         if ((old_termios->c_cflag & CRTSCTS) &&
1401             !(tty->termios->c_cflag & CRTSCTS)) {
1402                 tty->hw_stopped = 0;
1403                 rs_start(tty);
1404         }
1405
1406 #if 0
1407         /*
1408          * No need to wake up processes in open wait, since they
1409          * sample the CLOCAL flag once, and don't recheck it.
1410          * XXX  It's not clear whether the current behavior is correct
1411          * or not.  Hence, this may change.....
1412          */
1413         if (!(old_termios->c_cflag & CLOCAL) &&
1414             (tty->termios->c_cflag & CLOCAL))
1415                 wake_up_interruptible(&info->open_wait);
1416 #endif
1417 }
1418
1419 /*
1420  * ------------------------------------------------------------
1421  * rs_close()
1422  * 
1423  * This routine is called when the serial port gets closed.  First, we
1424  * wait for the last remaining data to be sent.  Then, we unlink its
1425  * async structure from the interrupt chain if necessary, and we free
1426  * that IRQ if nothing is left in the chain.
1427  * ------------------------------------------------------------
1428  */
1429 static void rs_close(struct tty_struct *tty, struct file * filp)
1430 {
1431         struct async_struct * info = (struct async_struct *)tty->driver_data;
1432         struct serial_state *state;
1433         unsigned long flags;
1434
1435         if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1436                 return;
1437
1438         state = info->state;
1439
1440         local_irq_save(flags);
1441
1442         if (tty_hung_up_p(filp)) {
1443                 DBG_CNT("before DEC-hung");
1444                 local_irq_restore(flags);
1445                 return;
1446         }
1447
1448 #ifdef SERIAL_DEBUG_OPEN
1449         printk("rs_close ttys%d, count = %d\n", info->line, state->count);
1450 #endif
1451         if ((tty->count == 1) && (state->count != 1)) {
1452                 /*
1453                  * Uh, oh.  tty->count is 1, which means that the tty
1454                  * structure will be freed.  state->count should always
1455                  * be one in these conditions.  If it's greater than
1456                  * one, we've got real problems, since it means the
1457                  * serial port won't be shutdown.
1458                  */
1459                 printk("rs_close: bad serial port count; tty->count is 1, "
1460                        "state->count is %d\n", state->count);
1461                 state->count = 1;
1462         }
1463         if (--state->count < 0) {
1464                 printk("rs_close: bad serial port count for ttys%d: %d\n",
1465                        info->line, state->count);
1466                 state->count = 0;
1467         }
1468         if (state->count) {
1469                 DBG_CNT("before DEC-2");
1470                 local_irq_restore(flags);
1471                 return;
1472         }
1473         info->flags |= ASYNC_CLOSING;
1474         /*
1475          * Now we wait for the transmit buffer to clear; and we notify 
1476          * the line discipline to only process XON/XOFF characters.
1477          */
1478         tty->closing = 1;
1479         if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1480                 tty_wait_until_sent(tty, info->closing_wait);
1481         /*
1482          * At this point we stop accepting input.  To do this, we
1483          * disable the receive line status interrupts, and tell the
1484          * interrupt driver to stop checking the data ready bit in the
1485          * line status register.
1486          */
1487         info->read_status_mask &= ~UART_LSR_DR;
1488         if (info->flags & ASYNC_INITIALIZED) {
1489                 /* disable receive interrupts */
1490                 custom.intena = IF_RBF;
1491                 mb();
1492                 /* clear any pending receive interrupt */
1493                 custom.intreq = IF_RBF;
1494                 mb();
1495
1496                 /*
1497                  * Before we drop DTR, make sure the UART transmitter
1498                  * has completely drained; this is especially
1499                  * important if there is a transmit FIFO!
1500                  */
1501                 rs_wait_until_sent(tty, info->timeout);
1502         }
1503         shutdown(info);
1504         if (tty->driver->flush_buffer)
1505                 tty->driver->flush_buffer(tty);
1506                 
1507         tty_ldisc_flush(tty);
1508         tty->closing = 0;
1509         info->event = 0;
1510         info->tty = NULL;
1511         if (info->blocked_open) {
1512                 if (info->close_delay) {
1513                         msleep_interruptible(jiffies_to_msecs(info->close_delay));
1514                 }
1515                 wake_up_interruptible(&info->open_wait);
1516         }
1517         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
1518         wake_up_interruptible(&info->close_wait);
1519         local_irq_restore(flags);
1520 }
1521
1522 /*
1523  * rs_wait_until_sent() --- wait until the transmitter is empty
1524  */
1525 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1526 {
1527         struct async_struct * info = (struct async_struct *)tty->driver_data;
1528         unsigned long orig_jiffies, char_time;
1529         int lsr;
1530
1531         if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
1532                 return;
1533
1534         if (info->xmit_fifo_size == 0)
1535                 return; /* Just in case.... */
1536
1537         orig_jiffies = jiffies;
1538         /*
1539          * Set the check interval to be 1/5 of the estimated time to
1540          * send a single character, and make it at least 1.  The check
1541          * interval should also be less than the timeout.
1542          * 
1543          * Note: we have to use pretty tight timings here to satisfy
1544          * the NIST-PCTS.
1545          */
1546         char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1547         char_time = char_time / 5;
1548         if (char_time == 0)
1549                 char_time = 1;
1550         if (timeout)
1551           char_time = min_t(unsigned long, char_time, timeout);
1552         /*
1553          * If the transmitter hasn't cleared in twice the approximate
1554          * amount of time to send the entire FIFO, it probably won't
1555          * ever clear.  This assumes the UART isn't doing flow
1556          * control, which is currently the case.  Hence, if it ever
1557          * takes longer than info->timeout, this is probably due to a
1558          * UART bug of some kind.  So, we clamp the timeout parameter at
1559          * 2*info->timeout.
1560          */
1561         if (!timeout || timeout > 2*info->timeout)
1562                 timeout = 2*info->timeout;
1563 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1564         printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
1565         printk("jiff=%lu...", jiffies);
1566 #endif
1567         while(!((lsr = custom.serdatr) & SDR_TSRE)) {
1568 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1569                 printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
1570 #endif
1571                 msleep_interruptible(jiffies_to_msecs(char_time));
1572                 if (signal_pending(current))
1573                         break;
1574                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
1575                         break;
1576         }
1577         current->state = TASK_RUNNING;
1578 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1579         printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1580 #endif
1581 }
1582
1583 /*
1584  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1585  */
1586 static void rs_hangup(struct tty_struct *tty)
1587 {
1588         struct async_struct * info = (struct async_struct *)tty->driver_data;
1589         struct serial_state *state = info->state;
1590
1591         if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1592                 return;
1593
1594         state = info->state;
1595
1596         rs_flush_buffer(tty);
1597         shutdown(info);
1598         info->event = 0;
1599         state->count = 0;
1600         info->flags &= ~ASYNC_NORMAL_ACTIVE;
1601         info->tty = NULL;
1602         wake_up_interruptible(&info->open_wait);
1603 }
1604
1605 /*
1606  * ------------------------------------------------------------
1607  * rs_open() and friends
1608  * ------------------------------------------------------------
1609  */
1610 static int block_til_ready(struct tty_struct *tty, struct file * filp,
1611                            struct async_struct *info)
1612 {
1613 #ifdef DECLARE_WAITQUEUE
1614         DECLARE_WAITQUEUE(wait, current);
1615 #else
1616         struct wait_queue wait = { current, NULL };
1617 #endif
1618         struct serial_state *state = info->state;
1619         int             retval;
1620         int             do_clocal = 0, extra_count = 0;
1621         unsigned long   flags;
1622
1623         /*
1624          * If the device is in the middle of being closed, then block
1625          * until it's done, and then try again.
1626          */
1627         if (tty_hung_up_p(filp) ||
1628             (info->flags & ASYNC_CLOSING)) {
1629                 if (info->flags & ASYNC_CLOSING)
1630                         interruptible_sleep_on(&info->close_wait);
1631 #ifdef SERIAL_DO_RESTART
1632                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
1633                         -EAGAIN : -ERESTARTSYS);
1634 #else
1635                 return -EAGAIN;
1636 #endif
1637         }
1638
1639         /*
1640          * If non-blocking mode is set, or the port is not enabled,
1641          * then make the check up front and then exit.
1642          */
1643         if ((filp->f_flags & O_NONBLOCK) ||
1644             (tty->flags & (1 << TTY_IO_ERROR))) {
1645                 info->flags |= ASYNC_NORMAL_ACTIVE;
1646                 return 0;
1647         }
1648
1649         if (tty->termios->c_cflag & CLOCAL)
1650                 do_clocal = 1;
1651
1652         /*
1653          * Block waiting for the carrier detect and the line to become
1654          * free (i.e., not in use by the callout).  While we are in
1655          * this loop, state->count is dropped by one, so that
1656          * rs_close() knows when to free things.  We restore it upon
1657          * exit, either normal or abnormal.
1658          */
1659         retval = 0;
1660         add_wait_queue(&info->open_wait, &wait);
1661 #ifdef SERIAL_DEBUG_OPEN
1662         printk("block_til_ready before block: ttys%d, count = %d\n",
1663                state->line, state->count);
1664 #endif
1665         local_irq_save(flags);
1666         if (!tty_hung_up_p(filp)) {
1667                 extra_count = 1;
1668                 state->count--;
1669         }
1670         local_irq_restore(flags);
1671         info->blocked_open++;
1672         while (1) {
1673                 local_irq_save(flags);
1674                 if (tty->termios->c_cflag & CBAUD)
1675                         rtsdtr_ctrl(SER_DTR|SER_RTS);
1676                 local_irq_restore(flags);
1677                 set_current_state(TASK_INTERRUPTIBLE);
1678                 if (tty_hung_up_p(filp) ||
1679                     !(info->flags & ASYNC_INITIALIZED)) {
1680 #ifdef SERIAL_DO_RESTART
1681                         if (info->flags & ASYNC_HUP_NOTIFY)
1682                                 retval = -EAGAIN;
1683                         else
1684                                 retval = -ERESTARTSYS;
1685 #else
1686                         retval = -EAGAIN;
1687 #endif
1688                         break;
1689                 }
1690                 if (!(info->flags & ASYNC_CLOSING) &&
1691                     (do_clocal || (!(ciab.pra & SER_DCD)) ))
1692                         break;
1693                 if (signal_pending(current)) {
1694                         retval = -ERESTARTSYS;
1695                         break;
1696                 }
1697 #ifdef SERIAL_DEBUG_OPEN
1698                 printk("block_til_ready blocking: ttys%d, count = %d\n",
1699                        info->line, state->count);
1700 #endif
1701                 schedule();
1702         }
1703         current->state = TASK_RUNNING;
1704         remove_wait_queue(&info->open_wait, &wait);
1705         if (extra_count)
1706                 state->count++;
1707         info->blocked_open--;
1708 #ifdef SERIAL_DEBUG_OPEN
1709         printk("block_til_ready after blocking: ttys%d, count = %d\n",
1710                info->line, state->count);
1711 #endif
1712         if (retval)
1713                 return retval;
1714         info->flags |= ASYNC_NORMAL_ACTIVE;
1715         return 0;
1716 }
1717
1718 static int get_async_struct(int line, struct async_struct **ret_info)
1719 {
1720         struct async_struct *info;
1721         struct serial_state *sstate;
1722
1723         sstate = rs_table + line;
1724         sstate->count++;
1725         if (sstate->info) {
1726                 *ret_info = sstate->info;
1727                 return 0;
1728         }
1729         info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
1730         if (!info) {
1731                 sstate->count--;
1732                 return -ENOMEM;
1733         }
1734         memset(info, 0, sizeof(struct async_struct));
1735 #ifdef DECLARE_WAITQUEUE
1736         init_waitqueue_head(&info->open_wait);
1737         init_waitqueue_head(&info->close_wait);
1738         init_waitqueue_head(&info->delta_msr_wait);
1739 #endif
1740         info->magic = SERIAL_MAGIC;
1741         info->port = sstate->port;
1742         info->flags = sstate->flags;
1743         info->xmit_fifo_size = sstate->xmit_fifo_size;
1744         info->line = line;
1745         tasklet_init(&info->tlet, do_softint, (unsigned long)info);
1746         info->state = sstate;
1747         if (sstate->info) {
1748                 kfree(info);
1749                 *ret_info = sstate->info;
1750                 return 0;
1751         }
1752         *ret_info = sstate->info = info;
1753         return 0;
1754 }
1755
1756 /*
1757  * This routine is called whenever a serial port is opened.  It
1758  * enables interrupts for a serial port, linking in its async structure into
1759  * the IRQ chain.   It also performs the serial-specific
1760  * initialization for the tty structure.
1761  */
1762 static int rs_open(struct tty_struct *tty, struct file * filp)
1763 {
1764         struct async_struct     *info;
1765         int                     retval, line;
1766
1767         line = tty->index;
1768         if ((line < 0) || (line >= NR_PORTS)) {
1769                 return -ENODEV;
1770         }
1771         retval = get_async_struct(line, &info);
1772         if (retval) {
1773                 return retval;
1774         }
1775         tty->driver_data = info;
1776         info->tty = tty;
1777         if (serial_paranoia_check(info, tty->name, "rs_open"))
1778                 return -ENODEV;
1779
1780 #ifdef SERIAL_DEBUG_OPEN
1781         printk("rs_open %s, count = %d\n", tty->name, info->state->count);
1782 #endif
1783         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1784
1785         /*
1786          * If the port is the middle of closing, bail out now
1787          */
1788         if (tty_hung_up_p(filp) ||
1789             (info->flags & ASYNC_CLOSING)) {
1790                 if (info->flags & ASYNC_CLOSING)
1791                         interruptible_sleep_on(&info->close_wait);
1792 #ifdef SERIAL_DO_RESTART
1793                 return ((info->flags & ASYNC_HUP_NOTIFY) ?
1794                         -EAGAIN : -ERESTARTSYS);
1795 #else
1796                 return -EAGAIN;
1797 #endif
1798         }
1799
1800         /*
1801          * Start up serial port
1802          */
1803         retval = startup(info);
1804         if (retval) {
1805                 return retval;
1806         }
1807
1808         retval = block_til_ready(tty, filp, info);
1809         if (retval) {
1810 #ifdef SERIAL_DEBUG_OPEN
1811                 printk("rs_open returning after block_til_ready with %d\n",
1812                        retval);
1813 #endif
1814                 return retval;
1815         }
1816
1817 #ifdef SERIAL_DEBUG_OPEN
1818         printk("rs_open %s successful...", tty->name);
1819 #endif
1820         return 0;
1821 }
1822
1823 /*
1824  * /proc fs routines....
1825  */
1826
1827 static inline int line_info(char *buf, struct serial_state *state)
1828 {
1829         struct async_struct *info = state->info, scr_info;
1830         char    stat_buf[30], control, status;
1831         int     ret;
1832         unsigned long flags;
1833
1834         ret = sprintf(buf, "%d: uart:amiga_builtin",state->line);
1835
1836         /*
1837          * Figure out the current RS-232 lines
1838          */
1839         if (!info) {
1840                 info = &scr_info;       /* This is just for serial_{in,out} */
1841
1842                 info->magic = SERIAL_MAGIC;
1843                 info->flags = state->flags;
1844                 info->quot = 0;
1845                 info->tty = NULL;
1846         }
1847         local_irq_save(flags);
1848         status = ciab.pra;
1849         control = info ? info->MCR : status;
1850         local_irq_restore(flags);
1851
1852         stat_buf[0] = 0;
1853         stat_buf[1] = 0;
1854         if(!(control & SER_RTS))
1855                 strcat(stat_buf, "|RTS");
1856         if(!(status & SER_CTS))
1857                 strcat(stat_buf, "|CTS");
1858         if(!(control & SER_DTR))
1859                 strcat(stat_buf, "|DTR");
1860         if(!(status & SER_DSR))
1861                 strcat(stat_buf, "|DSR");
1862         if(!(status & SER_DCD))
1863                 strcat(stat_buf, "|CD");
1864
1865         if (info->quot) {
1866                 ret += sprintf(buf+ret, " baud:%d",
1867                                state->baud_base / info->quot);
1868         }
1869
1870         ret += sprintf(buf+ret, " tx:%d rx:%d",
1871                       state->icount.tx, state->icount.rx);
1872
1873         if (state->icount.frame)
1874                 ret += sprintf(buf+ret, " fe:%d", state->icount.frame);
1875
1876         if (state->icount.parity)
1877                 ret += sprintf(buf+ret, " pe:%d", state->icount.parity);
1878
1879         if (state->icount.brk)
1880                 ret += sprintf(buf+ret, " brk:%d", state->icount.brk);
1881
1882         if (state->icount.overrun)
1883                 ret += sprintf(buf+ret, " oe:%d", state->icount.overrun);
1884
1885         /*
1886          * Last thing is the RS-232 status lines
1887          */
1888         ret += sprintf(buf+ret, " %s\n", stat_buf+1);
1889         return ret;
1890 }
1891
1892 static int rs_read_proc(char *page, char **start, off_t off, int count,
1893                         int *eof, void *data)
1894 {
1895         int len = 0, l;
1896         off_t   begin = 0;
1897
1898         len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
1899         l = line_info(page + len, &rs_table[0]);
1900         len += l;
1901         if (len+begin > off+count)
1902           goto done;
1903         if (len+begin < off) {
1904           begin += len;
1905           len = 0;
1906         }
1907         *eof = 1;
1908 done:
1909         if (off >= len+begin)
1910                 return 0;
1911         *start = page + (off-begin);
1912         return ((count < begin+len-off) ? count : begin+len-off);
1913 }
1914
1915 /*
1916  * ---------------------------------------------------------------------
1917  * rs_init() and friends
1918  *
1919  * rs_init() is called at boot-time to initialize the serial driver.
1920  * ---------------------------------------------------------------------
1921  */
1922
1923 /*
1924  * This routine prints out the appropriate serial driver version
1925  * number, and identifies which options were configured into this
1926  * driver.
1927  */
1928 static void show_serial_version(void)
1929 {
1930         printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
1931 }
1932
1933
1934 static const struct tty_operations serial_ops = {
1935         .open = rs_open,
1936         .close = rs_close,
1937         .write = rs_write,
1938         .put_char = rs_put_char,
1939         .flush_chars = rs_flush_chars,
1940         .write_room = rs_write_room,
1941         .chars_in_buffer = rs_chars_in_buffer,
1942         .flush_buffer = rs_flush_buffer,
1943         .ioctl = rs_ioctl,
1944         .throttle = rs_throttle,
1945         .unthrottle = rs_unthrottle,
1946         .set_termios = rs_set_termios,
1947         .stop = rs_stop,
1948         .start = rs_start,
1949         .hangup = rs_hangup,
1950         .break_ctl = rs_break,
1951         .send_xchar = rs_send_xchar,
1952         .wait_until_sent = rs_wait_until_sent,
1953         .read_proc = rs_read_proc,
1954         .tiocmget = rs_tiocmget,
1955         .tiocmset = rs_tiocmset,
1956 };
1957
1958 /*
1959  * The serial driver boot-time initialization code!
1960  */
1961 static int __init rs_init(void)
1962 {
1963         unsigned long flags;
1964         struct serial_state * state;
1965
1966         if (!MACH_IS_AMIGA || !AMIGAHW_PRESENT(AMI_SERIAL))
1967                 return -ENODEV;
1968
1969         serial_driver = alloc_tty_driver(1);
1970         if (!serial_driver)
1971                 return -ENOMEM;
1972
1973         /*
1974          *  We request SERDAT and SERPER only, because the serial registers are
1975          *  too spreaded over the custom register space
1976          */
1977         if (!request_mem_region(CUSTOM_PHYSADDR+0x30, 4, "amiserial [Paula]"))
1978                 return -EBUSY;
1979
1980         IRQ_ports = NULL;
1981
1982         show_serial_version();
1983
1984         /* Initialize the tty_driver structure */
1985
1986         serial_driver->owner = THIS_MODULE;
1987         serial_driver->driver_name = "amiserial";
1988         serial_driver->name = "ttyS";
1989         serial_driver->major = TTY_MAJOR;
1990         serial_driver->minor_start = 64;
1991         serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1992         serial_driver->subtype = SERIAL_TYPE_NORMAL;
1993         serial_driver->init_termios = tty_std_termios;
1994         serial_driver->init_termios.c_cflag =
1995                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1996         serial_driver->flags = TTY_DRIVER_REAL_RAW;
1997         tty_set_operations(serial_driver, &serial_ops);
1998
1999         if (tty_register_driver(serial_driver))
2000                 panic("Couldn't register serial driver\n");
2001
2002         state = rs_table;
2003         state->magic = SSTATE_MAGIC;
2004         state->port = (int)&custom.serdatr; /* Just to give it a value */
2005         state->line = 0;
2006         state->custom_divisor = 0;
2007         state->close_delay = 5*HZ/10;
2008         state->closing_wait = 30*HZ;
2009         state->icount.cts = state->icount.dsr = 
2010           state->icount.rng = state->icount.dcd = 0;
2011         state->icount.rx = state->icount.tx = 0;
2012         state->icount.frame = state->icount.parity = 0;
2013         state->icount.overrun = state->icount.brk = 0;
2014
2015         printk(KERN_INFO "ttyS%d is the amiga builtin serial port\n",
2016                        state->line);
2017
2018         /* Hardware set up */
2019
2020         state->baud_base = amiga_colorclock;
2021         state->xmit_fifo_size = 1;
2022
2023         local_irq_save(flags);
2024
2025         /* set ISRs, and then disable the rx interrupts */
2026         request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
2027         request_irq(IRQ_AMIGA_RBF, ser_rx_int, IRQF_DISABLED, "serial RX", state);
2028
2029         /* turn off Rx and Tx interrupts */
2030         custom.intena = IF_RBF | IF_TBE;
2031         mb();
2032
2033         /* clear any pending interrupt */
2034         custom.intreq = IF_RBF | IF_TBE;
2035         mb();
2036
2037         local_irq_restore(flags);
2038
2039         /*
2040          * set the appropriate directions for the modem control flags,
2041          * and clear RTS and DTR
2042          */
2043         ciab.ddra |= (SER_DTR | SER_RTS);   /* outputs */
2044         ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR);  /* inputs */
2045
2046         return 0;
2047 }
2048
2049 static __exit void rs_exit(void) 
2050 {
2051         int error;
2052         struct async_struct *info = rs_table[0].info;
2053
2054         /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
2055         tasklet_kill(&info->tlet);
2056         if ((error = tty_unregister_driver(serial_driver)))
2057                 printk("SERIAL: failed to unregister serial driver (%d)\n",
2058                        error);
2059         put_tty_driver(serial_driver);
2060
2061         if (info) {
2062           rs_table[0].info = NULL;
2063           kfree(info);
2064         }
2065
2066         release_mem_region(CUSTOM_PHYSADDR+0x30, 4);
2067 }
2068
2069 module_init(rs_init)
2070 module_exit(rs_exit)
2071
2072
2073 /*
2074  * ------------------------------------------------------------
2075  * Serial console driver
2076  * ------------------------------------------------------------
2077  */
2078 #ifdef CONFIG_SERIAL_CONSOLE
2079
2080 static void amiga_serial_putc(char c)
2081 {
2082         custom.serdat = (unsigned char)c | 0x100;
2083         while (!(custom.serdatr & 0x2000))
2084                 barrier();
2085 }
2086
2087 /*
2088  *      Print a string to the serial port trying not to disturb
2089  *      any possible real use of the port...
2090  *
2091  *      The console must be locked when we get here.
2092  */
2093 static void serial_console_write(struct console *co, const char *s,
2094                                 unsigned count)
2095 {
2096         unsigned short intena = custom.intenar;
2097
2098         custom.intena = IF_TBE;
2099
2100         while (count--) {
2101                 if (*s == '\n')
2102                         amiga_serial_putc('\r');
2103                 amiga_serial_putc(*s++);
2104         }
2105
2106         custom.intena = IF_SETCLR | (intena & IF_TBE);
2107 }
2108
2109 static struct tty_driver *serial_console_device(struct console *c, int *index)
2110 {
2111         *index = 0;
2112         return serial_driver;
2113 }
2114
2115 static struct console sercons = {
2116         .name =         "ttyS",
2117         .write =        serial_console_write,
2118         .device =       serial_console_device,
2119         .flags =        CON_PRINTBUFFER,
2120         .index =        -1,
2121 };
2122
2123 /*
2124  *      Register console.
2125  */
2126 static int __init amiserial_console_init(void)
2127 {
2128         register_console(&sercons);
2129         return 0;
2130 }
2131 console_initcall(amiserial_console_init);
2132 #endif
2133
2134 MODULE_LICENSE("GPL");