Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / tty / amiserial.c
1 /*
2  * Serial driver for the amiga builtin port.
3  *
4  * This code was created by taking serial.c version 4.30 from kernel
5  * release 2.3.22, replacing all hardware related stuff with the
6  * corresponding amiga hardware actions, and removing all irrelevant
7  * code. As a consequence, it uses many of the constants and names
8  * associated with the registers and bits of 16550 compatible UARTS -
9  * but only to keep track of status, etc in the state variables. It
10  * was done this was to make it easier to keep the code in line with
11  * (non hardware specific) changes to serial.c.
12  *
13  * The port is registered with the tty driver as minor device 64, and
14  * therefore other ports should should only use 65 upwards.
15  *
16  * Richard Lucock 28/12/99
17  *
18  *  Copyright (C) 1991, 1992  Linus Torvalds
19  *  Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 
20  *              1998, 1999  Theodore Ts'o
21  *
22  */
23
24 /*
25  * Serial driver configuration section.  Here are the various options:
26  *
27  * SERIAL_PARANOIA_CHECK
28  *              Check the magic number for the async_structure where
29  *              ever possible.
30  */
31
32 #include <linux/delay.h>
33
34 #undef SERIAL_PARANOIA_CHECK
35 #define SERIAL_DO_RESTART
36
37 /* Set of debugging defines */
38
39 #undef SERIAL_DEBUG_INTR
40 #undef SERIAL_DEBUG_OPEN
41 #undef SERIAL_DEBUG_FLOW
42 #undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
43
44 /* Sanity checks */
45
46 #if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
47 #define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
48  tty->name, (info->tport.flags), serial_driver->refcount,info->count,tty->count,s)
49 #else
50 #define DBG_CNT(s)
51 #endif
52
53 /*
54  * End of serial driver configuration section.
55  */
56
57 #include <linux/module.h>
58
59 #include <linux/types.h>
60 #include <linux/serial.h>
61 #include <linux/serial_reg.h>
62 static char *serial_version = "4.30";
63
64 #include <linux/errno.h>
65 #include <linux/signal.h>
66 #include <linux/sched.h>
67 #include <linux/kernel.h>
68 #include <linux/timer.h>
69 #include <linux/interrupt.h>
70 #include <linux/tty.h>
71 #include <linux/tty_flip.h>
72 #include <linux/circ_buf.h>
73 #include <linux/console.h>
74 #include <linux/major.h>
75 #include <linux/string.h>
76 #include <linux/fcntl.h>
77 #include <linux/ptrace.h>
78 #include <linux/ioport.h>
79 #include <linux/mm.h>
80 #include <linux/seq_file.h>
81 #include <linux/slab.h>
82 #include <linux/init.h>
83 #include <linux/bitops.h>
84 #include <linux/platform_device.h>
85
86 #include <asm/setup.h>
87
88
89 #include <asm/irq.h>
90
91 #include <asm/amigahw.h>
92 #include <asm/amigaints.h>
93
94 struct serial_state {
95         struct tty_port         tport;
96         struct circ_buf         xmit;
97         struct async_icount     icount;
98
99         unsigned long           port;
100         int                     baud_base;
101         int                     xmit_fifo_size;
102         int                     custom_divisor;
103         int                     read_status_mask;
104         int                     ignore_status_mask;
105         int                     timeout;
106         int                     quot;
107         int                     IER;    /* Interrupt Enable Register */
108         int                     MCR;    /* Modem control register */
109         int                     x_char; /* xon/xoff character */
110 };
111
112 #define custom amiga_custom
113 static char *serial_name = "Amiga-builtin serial driver";
114
115 static struct tty_driver *serial_driver;
116
117 /* number of characters left in xmit buffer before we ask for more */
118 #define WAKEUP_CHARS 256
119
120 static unsigned char current_ctl_bits;
121
122 static void change_speed(struct tty_struct *tty, struct serial_state *info,
123                 struct ktermios *old);
124 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
125
126
127 static struct serial_state rs_table[1];
128
129 #define NR_PORTS ARRAY_SIZE(rs_table)
130
131 #include <asm/uaccess.h>
132
133 #define serial_isroot() (capable(CAP_SYS_ADMIN))
134
135
136 static inline int serial_paranoia_check(struct serial_state *info,
137                                         char *name, const char *routine)
138 {
139 #ifdef SERIAL_PARANOIA_CHECK
140         static const char *badmagic =
141                 "Warning: bad magic number for serial struct (%s) in %s\n";
142         static const char *badinfo =
143                 "Warning: null async_struct for (%s) in %s\n";
144
145         if (!info) {
146                 printk(badinfo, name, routine);
147                 return 1;
148         }
149         if (info->magic != SERIAL_MAGIC) {
150                 printk(badmagic, name, routine);
151                 return 1;
152         }
153 #endif
154         return 0;
155 }
156
157 /* some serial hardware definitions */
158 #define SDR_OVRUN   (1<<15)
159 #define SDR_RBF     (1<<14)
160 #define SDR_TBE     (1<<13)
161 #define SDR_TSRE    (1<<12)
162
163 #define SERPER_PARENB    (1<<15)
164
165 #define AC_SETCLR   (1<<15)
166 #define AC_UARTBRK  (1<<11)
167
168 #define SER_DTR     (1<<7)
169 #define SER_RTS     (1<<6)
170 #define SER_DCD     (1<<5)
171 #define SER_CTS     (1<<4)
172 #define SER_DSR     (1<<3)
173
174 static __inline__ void rtsdtr_ctrl(int bits)
175 {
176     ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
177 }
178
179 /*
180  * ------------------------------------------------------------
181  * rs_stop() and rs_start()
182  *
183  * This routines are called before setting or resetting tty->stopped.
184  * They enable or disable transmitter interrupts, as necessary.
185  * ------------------------------------------------------------
186  */
187 static void rs_stop(struct tty_struct *tty)
188 {
189         struct serial_state *info = tty->driver_data;
190         unsigned long flags;
191
192         if (serial_paranoia_check(info, tty->name, "rs_stop"))
193                 return;
194
195         local_irq_save(flags);
196         if (info->IER & UART_IER_THRI) {
197                 info->IER &= ~UART_IER_THRI;
198                 /* disable Tx interrupt and remove any pending interrupts */
199                 custom.intena = IF_TBE;
200                 mb();
201                 custom.intreq = IF_TBE;
202                 mb();
203         }
204         local_irq_restore(flags);
205 }
206
207 static void rs_start(struct tty_struct *tty)
208 {
209         struct serial_state *info = tty->driver_data;
210         unsigned long flags;
211
212         if (serial_paranoia_check(info, tty->name, "rs_start"))
213                 return;
214
215         local_irq_save(flags);
216         if (info->xmit.head != info->xmit.tail
217             && info->xmit.buf
218             && !(info->IER & UART_IER_THRI)) {
219                 info->IER |= UART_IER_THRI;
220                 custom.intena = IF_SETCLR | IF_TBE;
221                 mb();
222                 /* set a pending Tx Interrupt, transmitter should restart now */
223                 custom.intreq = IF_SETCLR | IF_TBE;
224                 mb();
225         }
226         local_irq_restore(flags);
227 }
228
229 /*
230  * ----------------------------------------------------------------------
231  *
232  * Here starts the interrupt handling routines.  All of the following
233  * subroutines are declared as inline and are folded into
234  * rs_interrupt().  They were separated out for readability's sake.
235  *
236  * Note: rs_interrupt() is a "fast" interrupt, which means that it
237  * runs with interrupts turned off.  People who may want to modify
238  * rs_interrupt() should try to keep the interrupt handler as fast as
239  * possible.  After you are done making modifications, it is not a bad
240  * idea to do:
241  * 
242  * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
243  *
244  * and look at the resulting assemble code in serial.s.
245  *
246  *                              - Ted Ts'o (tytso@mit.edu), 7-Mar-93
247  * -----------------------------------------------------------------------
248  */
249
250 static void receive_chars(struct serial_state *info)
251 {
252         int status;
253         int serdatr;
254         struct tty_struct *tty = info->tport.tty;
255         unsigned char ch, flag;
256         struct  async_icount *icount;
257         int oe = 0;
258
259         icount = &info->icount;
260
261         status = UART_LSR_DR; /* We obviously have a character! */
262         serdatr = custom.serdatr;
263         mb();
264         custom.intreq = IF_RBF;
265         mb();
266
267         if((serdatr & 0x1ff) == 0)
268             status |= UART_LSR_BI;
269         if(serdatr & SDR_OVRUN)
270             status |= UART_LSR_OE;
271
272         ch = serdatr & 0xff;
273         icount->rx++;
274
275 #ifdef SERIAL_DEBUG_INTR
276         printk("DR%02x:%02x...", ch, status);
277 #endif
278         flag = TTY_NORMAL;
279
280         /*
281          * We don't handle parity or frame errors - but I have left
282          * the code in, since I'm not sure that the errors can't be
283          * detected.
284          */
285
286         if (status & (UART_LSR_BI | UART_LSR_PE |
287                       UART_LSR_FE | UART_LSR_OE)) {
288           /*
289            * For statistics only
290            */
291           if (status & UART_LSR_BI) {
292             status &= ~(UART_LSR_FE | UART_LSR_PE);
293             icount->brk++;
294           } else if (status & UART_LSR_PE)
295             icount->parity++;
296           else if (status & UART_LSR_FE)
297             icount->frame++;
298           if (status & UART_LSR_OE)
299             icount->overrun++;
300
301           /*
302            * Now check to see if character should be
303            * ignored, and mask off conditions which
304            * should be ignored.
305            */
306           if (status & info->ignore_status_mask)
307             goto out;
308
309           status &= info->read_status_mask;
310
311           if (status & (UART_LSR_BI)) {
312 #ifdef SERIAL_DEBUG_INTR
313             printk("handling break....");
314 #endif
315             flag = TTY_BREAK;
316             if (info->tport.flags & ASYNC_SAK)
317               do_SAK(tty);
318           } else if (status & UART_LSR_PE)
319             flag = TTY_PARITY;
320           else if (status & UART_LSR_FE)
321             flag = TTY_FRAME;
322           if (status & UART_LSR_OE) {
323             /*
324              * Overrun is special, since it's
325              * reported immediately, and doesn't
326              * affect the current character
327              */
328              oe = 1;
329           }
330         }
331         tty_insert_flip_char(tty, ch, flag);
332         if (oe == 1)
333                 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
334         tty_flip_buffer_push(tty);
335 out:
336         return;
337 }
338
339 static void transmit_chars(struct serial_state *info)
340 {
341         custom.intreq = IF_TBE;
342         mb();
343         if (info->x_char) {
344                 custom.serdat = info->x_char | 0x100;
345                 mb();
346                 info->icount.tx++;
347                 info->x_char = 0;
348                 return;
349         }
350         if (info->xmit.head == info->xmit.tail
351             || info->tport.tty->stopped
352             || info->tport.tty->hw_stopped) {
353                 info->IER &= ~UART_IER_THRI;
354                 custom.intena = IF_TBE;
355                 mb();
356                 return;
357         }
358
359         custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
360         mb();
361         info->xmit.tail = info->xmit.tail & (SERIAL_XMIT_SIZE-1);
362         info->icount.tx++;
363
364         if (CIRC_CNT(info->xmit.head,
365                      info->xmit.tail,
366                      SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
367                 tty_wakeup(info->tport.tty);
368
369 #ifdef SERIAL_DEBUG_INTR
370         printk("THRE...");
371 #endif
372         if (info->xmit.head == info->xmit.tail) {
373                 custom.intena = IF_TBE;
374                 mb();
375                 info->IER &= ~UART_IER_THRI;
376         }
377 }
378
379 static void check_modem_status(struct serial_state *info)
380 {
381         struct tty_port *port = &info->tport;
382         unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
383         unsigned char dstatus;
384         struct  async_icount *icount;
385
386         /* Determine bits that have changed */
387         dstatus = status ^ current_ctl_bits;
388         current_ctl_bits = status;
389
390         if (dstatus) {
391                 icount = &info->icount;
392                 /* update input line counters */
393                 if (dstatus & SER_DSR)
394                         icount->dsr++;
395                 if (dstatus & SER_DCD) {
396                         icount->dcd++;
397 #ifdef CONFIG_HARD_PPS
398                         if ((port->flags & ASYNC_HARDPPS_CD) &&
399                             !(status & SER_DCD))
400                                 hardpps();
401 #endif
402                 }
403                 if (dstatus & SER_CTS)
404                         icount->cts++;
405                 wake_up_interruptible(&port->delta_msr_wait);
406         }
407
408         if ((port->flags & ASYNC_CHECK_CD) && (dstatus & SER_DCD)) {
409 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
410                 printk("ttyS%d CD now %s...", info->line,
411                        (!(status & SER_DCD)) ? "on" : "off");
412 #endif
413                 if (!(status & SER_DCD))
414                         wake_up_interruptible(&port->open_wait);
415                 else {
416 #ifdef SERIAL_DEBUG_OPEN
417                         printk("doing serial hangup...");
418 #endif
419                         if (port->tty)
420                                 tty_hangup(port->tty);
421                 }
422         }
423         if (port->flags & ASYNC_CTS_FLOW) {
424                 if (port->tty->hw_stopped) {
425                         if (!(status & SER_CTS)) {
426 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
427                                 printk("CTS tx start...");
428 #endif
429                                 port->tty->hw_stopped = 0;
430                                 info->IER |= UART_IER_THRI;
431                                 custom.intena = IF_SETCLR | IF_TBE;
432                                 mb();
433                                 /* set a pending Tx Interrupt, transmitter should restart now */
434                                 custom.intreq = IF_SETCLR | IF_TBE;
435                                 mb();
436                                 tty_wakeup(port->tty);
437                                 return;
438                         }
439                 } else {
440                         if ((status & SER_CTS)) {
441 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
442                                 printk("CTS tx stop...");
443 #endif
444                                 port->tty->hw_stopped = 1;
445                                 info->IER &= ~UART_IER_THRI;
446                                 /* disable Tx interrupt and remove any pending interrupts */
447                                 custom.intena = IF_TBE;
448                                 mb();
449                                 custom.intreq = IF_TBE;
450                                 mb();
451                         }
452                 }
453         }
454 }
455
456 static irqreturn_t ser_vbl_int( int irq, void *data)
457 {
458         /* vbl is just a periodic interrupt we tie into to update modem status */
459         struct serial_state *info = data;
460         /*
461          * TBD - is it better to unregister from this interrupt or to
462          * ignore it if MSI is clear ?
463          */
464         if(info->IER & UART_IER_MSI)
465           check_modem_status(info);
466         return IRQ_HANDLED;
467 }
468
469 static irqreturn_t ser_rx_int(int irq, void *dev_id)
470 {
471         struct serial_state *info = dev_id;
472
473 #ifdef SERIAL_DEBUG_INTR
474         printk("ser_rx_int...");
475 #endif
476
477         if (!info->tport.tty)
478                 return IRQ_NONE;
479
480         receive_chars(info);
481 #ifdef SERIAL_DEBUG_INTR
482         printk("end.\n");
483 #endif
484         return IRQ_HANDLED;
485 }
486
487 static irqreturn_t ser_tx_int(int irq, void *dev_id)
488 {
489         struct serial_state *info = dev_id;
490
491         if (custom.serdatr & SDR_TBE) {
492 #ifdef SERIAL_DEBUG_INTR
493           printk("ser_tx_int...");
494 #endif
495
496           if (!info->tport.tty)
497                 return IRQ_NONE;
498
499           transmit_chars(info);
500 #ifdef SERIAL_DEBUG_INTR
501           printk("end.\n");
502 #endif
503         }
504         return IRQ_HANDLED;
505 }
506
507 /*
508  * -------------------------------------------------------------------
509  * Here ends the serial interrupt routines.
510  * -------------------------------------------------------------------
511  */
512
513 /*
514  * ---------------------------------------------------------------
515  * Low level utility subroutines for the serial driver:  routines to
516  * figure out the appropriate timeout for an interrupt chain, routines
517  * to initialize and startup a serial port, and routines to shutdown a
518  * serial port.  Useful stuff like that.
519  * ---------------------------------------------------------------
520  */
521
522 static int startup(struct tty_struct *tty, struct serial_state *info)
523 {
524         struct tty_port *port = &info->tport;
525         unsigned long flags;
526         int     retval=0;
527         unsigned long page;
528
529         page = get_zeroed_page(GFP_KERNEL);
530         if (!page)
531                 return -ENOMEM;
532
533         local_irq_save(flags);
534
535         if (port->flags & ASYNC_INITIALIZED) {
536                 free_page(page);
537                 goto errout;
538         }
539
540         if (info->xmit.buf)
541                 free_page(page);
542         else
543                 info->xmit.buf = (unsigned char *) page;
544
545 #ifdef SERIAL_DEBUG_OPEN
546         printk("starting up ttys%d ...", info->line);
547 #endif
548
549         /* Clear anything in the input buffer */
550
551         custom.intreq = IF_RBF;
552         mb();
553
554         retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
555         if (retval) {
556           if (serial_isroot()) {
557               set_bit(TTY_IO_ERROR, &tty->flags);
558             retval = 0;
559           }
560           goto errout;
561         }
562
563         /* enable both Rx and Tx interrupts */
564         custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
565         mb();
566         info->IER = UART_IER_MSI;
567
568         /* remember current state of the DCD and CTS bits */
569         current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
570
571         info->MCR = 0;
572         if (C_BAUD(tty))
573           info->MCR = SER_DTR | SER_RTS;
574         rtsdtr_ctrl(info->MCR);
575
576         clear_bit(TTY_IO_ERROR, &tty->flags);
577         info->xmit.head = info->xmit.tail = 0;
578
579         /*
580          * Set up the tty->alt_speed kludge
581          */
582         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
583                 tty->alt_speed = 57600;
584         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
585                 tty->alt_speed = 115200;
586         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
587                 tty->alt_speed = 230400;
588         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
589                 tty->alt_speed = 460800;
590
591         /*
592          * and set the speed of the serial port
593          */
594         change_speed(tty, info, NULL);
595
596         port->flags |= ASYNC_INITIALIZED;
597         local_irq_restore(flags);
598         return 0;
599
600 errout:
601         local_irq_restore(flags);
602         return retval;
603 }
604
605 /*
606  * This routine will shutdown a serial port; interrupts are disabled, and
607  * DTR is dropped if the hangup on close termio flag is on.
608  */
609 static void shutdown(struct tty_struct *tty, struct serial_state *info)
610 {
611         unsigned long   flags;
612         struct serial_state *state;
613
614         if (!(info->tport.flags & ASYNC_INITIALIZED))
615                 return;
616
617         state = info;
618
619 #ifdef SERIAL_DEBUG_OPEN
620         printk("Shutting down serial port %d ....\n", info->line);
621 #endif
622
623         local_irq_save(flags); /* Disable interrupts */
624
625         /*
626          * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
627          * here so the queue might never be waken up
628          */
629         wake_up_interruptible(&info->tport.delta_msr_wait);
630
631         /*
632          * Free the IRQ, if necessary
633          */
634         free_irq(IRQ_AMIGA_VERTB, info);
635
636         if (info->xmit.buf) {
637                 free_page((unsigned long) info->xmit.buf);
638                 info->xmit.buf = NULL;
639         }
640
641         info->IER = 0;
642         custom.intena = IF_RBF | IF_TBE;
643         mb();
644
645         /* disable break condition */
646         custom.adkcon = AC_UARTBRK;
647         mb();
648
649         if (tty->termios->c_cflag & HUPCL)
650                 info->MCR &= ~(SER_DTR|SER_RTS);
651         rtsdtr_ctrl(info->MCR);
652
653         set_bit(TTY_IO_ERROR, &tty->flags);
654
655         info->tport.flags &= ~ASYNC_INITIALIZED;
656         local_irq_restore(flags);
657 }
658
659
660 /*
661  * This routine is called to set the UART divisor registers to match
662  * the specified baud rate for a serial port.
663  */
664 static void change_speed(struct tty_struct *tty, struct serial_state *info,
665                          struct ktermios *old_termios)
666 {
667         struct tty_port *port = &info->tport;
668         int     quot = 0, baud_base, baud;
669         unsigned cflag, cval = 0;
670         int     bits;
671         unsigned long   flags;
672
673         cflag = tty->termios->c_cflag;
674
675         /* Byte size is always 8 bits plus parity bit if requested */
676
677         cval = 3; bits = 10;
678         if (cflag & CSTOPB) {
679                 cval |= 0x04;
680                 bits++;
681         }
682         if (cflag & PARENB) {
683                 cval |= UART_LCR_PARITY;
684                 bits++;
685         }
686         if (!(cflag & PARODD))
687                 cval |= UART_LCR_EPAR;
688 #ifdef CMSPAR
689         if (cflag & CMSPAR)
690                 cval |= UART_LCR_SPAR;
691 #endif
692
693         /* Determine divisor based on baud rate */
694         baud = tty_get_baud_rate(tty);
695         if (!baud)
696                 baud = 9600;    /* B0 transition handled in rs_set_termios */
697         baud_base = info->baud_base;
698         if (baud == 38400 && (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
699                 quot = info->custom_divisor;
700         else {
701                 if (baud == 134)
702                         /* Special case since 134 is really 134.5 */
703                         quot = (2*baud_base / 269);
704                 else if (baud)
705                         quot = baud_base / baud;
706         }
707         /* If the quotient is zero refuse the change */
708         if (!quot && old_termios) {
709                 /* FIXME: Will need updating for new tty in the end */
710                 tty->termios->c_cflag &= ~CBAUD;
711                 tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
712                 baud = tty_get_baud_rate(tty);
713                 if (!baud)
714                         baud = 9600;
715                 if (baud == 38400 &&
716                     (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
717                         quot = info->custom_divisor;
718                 else {
719                         if (baud == 134)
720                                 /* Special case since 134 is really 134.5 */
721                                 quot = (2*baud_base / 269);
722                         else if (baud)
723                                 quot = baud_base / baud;
724                 }
725         }
726         /* As a last resort, if the quotient is zero, default to 9600 bps */
727         if (!quot)
728                 quot = baud_base / 9600;
729         info->quot = quot;
730         info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
731         info->timeout += HZ/50;         /* Add .02 seconds of slop */
732
733         /* CTS flow control flag and modem status interrupts */
734         info->IER &= ~UART_IER_MSI;
735         if (port->flags & ASYNC_HARDPPS_CD)
736                 info->IER |= UART_IER_MSI;
737         if (cflag & CRTSCTS) {
738                 port->flags |= ASYNC_CTS_FLOW;
739                 info->IER |= UART_IER_MSI;
740         } else
741                 port->flags &= ~ASYNC_CTS_FLOW;
742         if (cflag & CLOCAL)
743                 port->flags &= ~ASYNC_CHECK_CD;
744         else {
745                 port->flags |= ASYNC_CHECK_CD;
746                 info->IER |= UART_IER_MSI;
747         }
748         /* TBD:
749          * Does clearing IER_MSI imply that we should disable the VBL interrupt ?
750          */
751
752         /*
753          * Set up parity check flag
754          */
755
756         info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
757         if (I_INPCK(tty))
758                 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
759         if (I_BRKINT(tty) || I_PARMRK(tty))
760                 info->read_status_mask |= UART_LSR_BI;
761
762         /*
763          * Characters to ignore
764          */
765         info->ignore_status_mask = 0;
766         if (I_IGNPAR(tty))
767                 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
768         if (I_IGNBRK(tty)) {
769                 info->ignore_status_mask |= UART_LSR_BI;
770                 /*
771                  * If we're ignore parity and break indicators, ignore 
772                  * overruns too.  (For real raw support).
773                  */
774                 if (I_IGNPAR(tty))
775                         info->ignore_status_mask |= UART_LSR_OE;
776         }
777         /*
778          * !!! ignore all characters if CREAD is not set
779          */
780         if ((cflag & CREAD) == 0)
781                 info->ignore_status_mask |= UART_LSR_DR;
782         local_irq_save(flags);
783
784         {
785           short serper;
786
787         /* Set up the baud rate */
788           serper = quot - 1;
789
790         /* Enable or disable parity bit */
791
792         if(cval & UART_LCR_PARITY)
793           serper |= (SERPER_PARENB);
794
795         custom.serper = serper;
796         mb();
797         }
798
799         local_irq_restore(flags);
800 }
801
802 static int rs_put_char(struct tty_struct *tty, unsigned char ch)
803 {
804         struct serial_state *info;
805         unsigned long flags;
806
807         info = tty->driver_data;
808
809         if (serial_paranoia_check(info, tty->name, "rs_put_char"))
810                 return 0;
811
812         if (!info->xmit.buf)
813                 return 0;
814
815         local_irq_save(flags);
816         if (CIRC_SPACE(info->xmit.head,
817                        info->xmit.tail,
818                        SERIAL_XMIT_SIZE) == 0) {
819                 local_irq_restore(flags);
820                 return 0;
821         }
822
823         info->xmit.buf[info->xmit.head++] = ch;
824         info->xmit.head &= SERIAL_XMIT_SIZE-1;
825         local_irq_restore(flags);
826         return 1;
827 }
828
829 static void rs_flush_chars(struct tty_struct *tty)
830 {
831         struct serial_state *info = tty->driver_data;
832         unsigned long flags;
833
834         if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
835                 return;
836
837         if (info->xmit.head == info->xmit.tail
838             || tty->stopped
839             || tty->hw_stopped
840             || !info->xmit.buf)
841                 return;
842
843         local_irq_save(flags);
844         info->IER |= UART_IER_THRI;
845         custom.intena = IF_SETCLR | IF_TBE;
846         mb();
847         /* set a pending Tx Interrupt, transmitter should restart now */
848         custom.intreq = IF_SETCLR | IF_TBE;
849         mb();
850         local_irq_restore(flags);
851 }
852
853 static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
854 {
855         int     c, ret = 0;
856         struct serial_state *info = tty->driver_data;
857         unsigned long flags;
858
859         if (serial_paranoia_check(info, tty->name, "rs_write"))
860                 return 0;
861
862         if (!info->xmit.buf)
863                 return 0;
864
865         local_irq_save(flags);
866         while (1) {
867                 c = CIRC_SPACE_TO_END(info->xmit.head,
868                                       info->xmit.tail,
869                                       SERIAL_XMIT_SIZE);
870                 if (count < c)
871                         c = count;
872                 if (c <= 0) {
873                         break;
874                 }
875                 memcpy(info->xmit.buf + info->xmit.head, buf, c);
876                 info->xmit.head = ((info->xmit.head + c) &
877                                    (SERIAL_XMIT_SIZE-1));
878                 buf += c;
879                 count -= c;
880                 ret += c;
881         }
882         local_irq_restore(flags);
883
884         if (info->xmit.head != info->xmit.tail
885             && !tty->stopped
886             && !tty->hw_stopped
887             && !(info->IER & UART_IER_THRI)) {
888                 info->IER |= UART_IER_THRI;
889                 local_irq_disable();
890                 custom.intena = IF_SETCLR | IF_TBE;
891                 mb();
892                 /* set a pending Tx Interrupt, transmitter should restart now */
893                 custom.intreq = IF_SETCLR | IF_TBE;
894                 mb();
895                 local_irq_restore(flags);
896         }
897         return ret;
898 }
899
900 static int rs_write_room(struct tty_struct *tty)
901 {
902         struct serial_state *info = tty->driver_data;
903
904         if (serial_paranoia_check(info, tty->name, "rs_write_room"))
905                 return 0;
906         return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
907 }
908
909 static int rs_chars_in_buffer(struct tty_struct *tty)
910 {
911         struct serial_state *info = tty->driver_data;
912
913         if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
914                 return 0;
915         return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
916 }
917
918 static void rs_flush_buffer(struct tty_struct *tty)
919 {
920         struct serial_state *info = tty->driver_data;
921         unsigned long flags;
922
923         if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
924                 return;
925         local_irq_save(flags);
926         info->xmit.head = info->xmit.tail = 0;
927         local_irq_restore(flags);
928         tty_wakeup(tty);
929 }
930
931 /*
932  * This function is used to send a high-priority XON/XOFF character to
933  * the device
934  */
935 static void rs_send_xchar(struct tty_struct *tty, char ch)
936 {
937         struct serial_state *info = tty->driver_data;
938         unsigned long flags;
939
940         if (serial_paranoia_check(info, tty->name, "rs_send_char"))
941                 return;
942
943         info->x_char = ch;
944         if (ch) {
945                 /* Make sure transmit interrupts are on */
946
947                 /* Check this ! */
948                 local_irq_save(flags);
949                 if(!(custom.intenar & IF_TBE)) {
950                     custom.intena = IF_SETCLR | IF_TBE;
951                     mb();
952                     /* set a pending Tx Interrupt, transmitter should restart now */
953                     custom.intreq = IF_SETCLR | IF_TBE;
954                     mb();
955                 }
956                 local_irq_restore(flags);
957
958                 info->IER |= UART_IER_THRI;
959         }
960 }
961
962 /*
963  * ------------------------------------------------------------
964  * rs_throttle()
965  * 
966  * This routine is called by the upper-layer tty layer to signal that
967  * incoming characters should be throttled.
968  * ------------------------------------------------------------
969  */
970 static void rs_throttle(struct tty_struct * tty)
971 {
972         struct serial_state *info = tty->driver_data;
973         unsigned long flags;
974 #ifdef SERIAL_DEBUG_THROTTLE
975         char    buf[64];
976
977         printk("throttle %s: %d....\n", tty_name(tty, buf),
978                tty->ldisc.chars_in_buffer(tty));
979 #endif
980
981         if (serial_paranoia_check(info, tty->name, "rs_throttle"))
982                 return;
983
984         if (I_IXOFF(tty))
985                 rs_send_xchar(tty, STOP_CHAR(tty));
986
987         if (tty->termios->c_cflag & CRTSCTS)
988                 info->MCR &= ~SER_RTS;
989
990         local_irq_save(flags);
991         rtsdtr_ctrl(info->MCR);
992         local_irq_restore(flags);
993 }
994
995 static void rs_unthrottle(struct tty_struct * tty)
996 {
997         struct serial_state *info = tty->driver_data;
998         unsigned long flags;
999 #ifdef SERIAL_DEBUG_THROTTLE
1000         char    buf[64];
1001
1002         printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1003                tty->ldisc.chars_in_buffer(tty));
1004 #endif
1005
1006         if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1007                 return;
1008
1009         if (I_IXOFF(tty)) {
1010                 if (info->x_char)
1011                         info->x_char = 0;
1012                 else
1013                         rs_send_xchar(tty, START_CHAR(tty));
1014         }
1015         if (tty->termios->c_cflag & CRTSCTS)
1016                 info->MCR |= SER_RTS;
1017         local_irq_save(flags);
1018         rtsdtr_ctrl(info->MCR);
1019         local_irq_restore(flags);
1020 }
1021
1022 /*
1023  * ------------------------------------------------------------
1024  * rs_ioctl() and friends
1025  * ------------------------------------------------------------
1026  */
1027
1028 static int get_serial_info(struct tty_struct *tty, struct serial_state *state,
1029                            struct serial_struct __user * retinfo)
1030 {
1031         struct serial_struct tmp;
1032    
1033         if (!retinfo)
1034                 return -EFAULT;
1035         memset(&tmp, 0, sizeof(tmp));
1036         tty_lock();
1037         tmp.line = tty->index;
1038         tmp.port = state->port;
1039         tmp.flags = state->tport.flags;
1040         tmp.xmit_fifo_size = state->xmit_fifo_size;
1041         tmp.baud_base = state->baud_base;
1042         tmp.close_delay = state->tport.close_delay;
1043         tmp.closing_wait = state->tport.closing_wait;
1044         tmp.custom_divisor = state->custom_divisor;
1045         tty_unlock();
1046         if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1047                 return -EFAULT;
1048         return 0;
1049 }
1050
1051 static int set_serial_info(struct tty_struct *tty, struct serial_state *state,
1052                            struct serial_struct __user * new_info)
1053 {
1054         struct tty_port *port = &state->tport;
1055         struct serial_struct new_serial;
1056         bool change_spd;
1057         int                     retval = 0;
1058
1059         if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1060                 return -EFAULT;
1061
1062         tty_lock();
1063         change_spd = ((new_serial.flags ^ port->flags) & ASYNC_SPD_MASK) ||
1064                 new_serial.custom_divisor != state->custom_divisor;
1065         if (new_serial.irq || new_serial.port != state->port ||
1066                         new_serial.xmit_fifo_size != state->xmit_fifo_size) {
1067                 tty_unlock();
1068                 return -EINVAL;
1069         }
1070   
1071         if (!serial_isroot()) {
1072                 if ((new_serial.baud_base != state->baud_base) ||
1073                     (new_serial.close_delay != port->close_delay) ||
1074                     (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
1075                     ((new_serial.flags & ~ASYNC_USR_MASK) !=
1076                      (port->flags & ~ASYNC_USR_MASK))) {
1077                         tty_unlock();
1078                         return -EPERM;
1079                 }
1080                 port->flags = ((port->flags & ~ASYNC_USR_MASK) |
1081                                (new_serial.flags & ASYNC_USR_MASK));
1082                 state->custom_divisor = new_serial.custom_divisor;
1083                 goto check_and_exit;
1084         }
1085
1086         if (new_serial.baud_base < 9600) {
1087                 tty_unlock();
1088                 return -EINVAL;
1089         }
1090
1091         /*
1092          * OK, past this point, all the error checking has been done.
1093          * At this point, we start making changes.....
1094          */
1095
1096         state->baud_base = new_serial.baud_base;
1097         port->flags = ((port->flags & ~ASYNC_FLAGS) |
1098                         (new_serial.flags & ASYNC_FLAGS));
1099         state->custom_divisor = new_serial.custom_divisor;
1100         port->close_delay = new_serial.close_delay * HZ/100;
1101         port->closing_wait = new_serial.closing_wait * HZ/100;
1102         tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1103
1104 check_and_exit:
1105         if (port->flags & ASYNC_INITIALIZED) {
1106                 if (change_spd) {
1107                         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1108                                 tty->alt_speed = 57600;
1109                         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1110                                 tty->alt_speed = 115200;
1111                         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1112                                 tty->alt_speed = 230400;
1113                         if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1114                                 tty->alt_speed = 460800;
1115                         change_speed(tty, state, NULL);
1116                 }
1117         } else
1118                 retval = startup(tty, state);
1119         tty_unlock();
1120         return retval;
1121 }
1122
1123
1124 /*
1125  * get_lsr_info - get line status register info
1126  *
1127  * Purpose: Let user call ioctl() to get info when the UART physically
1128  *          is emptied.  On bus types like RS485, the transmitter must
1129  *          release the bus after transmitting. This must be done when
1130  *          the transmit shift register is empty, not be done when the
1131  *          transmit holding register is empty.  This functionality
1132  *          allows an RS485 driver to be written in user space. 
1133  */
1134 static int get_lsr_info(struct serial_state *info, unsigned int __user *value)
1135 {
1136         unsigned char status;
1137         unsigned int result;
1138         unsigned long flags;
1139
1140         local_irq_save(flags);
1141         status = custom.serdatr;
1142         mb();
1143         local_irq_restore(flags);
1144         result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
1145         if (copy_to_user(value, &result, sizeof(int)))
1146                 return -EFAULT;
1147         return 0;
1148 }
1149
1150
1151 static int rs_tiocmget(struct tty_struct *tty)
1152 {
1153         struct serial_state *info = tty->driver_data;
1154         unsigned char control, status;
1155         unsigned long flags;
1156
1157         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1158                 return -ENODEV;
1159         if (tty->flags & (1 << TTY_IO_ERROR))
1160                 return -EIO;
1161
1162         control = info->MCR;
1163         local_irq_save(flags);
1164         status = ciab.pra;
1165         local_irq_restore(flags);
1166         return    ((control & SER_RTS) ? TIOCM_RTS : 0)
1167                 | ((control & SER_DTR) ? TIOCM_DTR : 0)
1168                 | (!(status  & SER_DCD) ? TIOCM_CAR : 0)
1169                 | (!(status  & SER_DSR) ? TIOCM_DSR : 0)
1170                 | (!(status  & SER_CTS) ? TIOCM_CTS : 0);
1171 }
1172
1173 static int rs_tiocmset(struct tty_struct *tty, unsigned int set,
1174                                                 unsigned int clear)
1175 {
1176         struct serial_state *info = tty->driver_data;
1177         unsigned long flags;
1178
1179         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1180                 return -ENODEV;
1181         if (tty->flags & (1 << TTY_IO_ERROR))
1182                 return -EIO;
1183
1184         local_irq_save(flags);
1185         if (set & TIOCM_RTS)
1186                 info->MCR |= SER_RTS;
1187         if (set & TIOCM_DTR)
1188                 info->MCR |= SER_DTR;
1189         if (clear & TIOCM_RTS)
1190                 info->MCR &= ~SER_RTS;
1191         if (clear & TIOCM_DTR)
1192                 info->MCR &= ~SER_DTR;
1193         rtsdtr_ctrl(info->MCR);
1194         local_irq_restore(flags);
1195         return 0;
1196 }
1197
1198 /*
1199  * rs_break() --- routine which turns the break handling on or off
1200  */
1201 static int rs_break(struct tty_struct *tty, int break_state)
1202 {
1203         struct serial_state *info = tty->driver_data;
1204         unsigned long flags;
1205
1206         if (serial_paranoia_check(info, tty->name, "rs_break"))
1207                 return -EINVAL;
1208
1209         local_irq_save(flags);
1210         if (break_state == -1)
1211           custom.adkcon = AC_SETCLR | AC_UARTBRK;
1212         else
1213           custom.adkcon = AC_UARTBRK;
1214         mb();
1215         local_irq_restore(flags);
1216         return 0;
1217 }
1218
1219 /*
1220  * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1221  * Return: write counters to the user passed counter struct
1222  * NB: both 1->0 and 0->1 transitions are counted except for
1223  *     RI where only 0->1 is counted.
1224  */
1225 static int rs_get_icount(struct tty_struct *tty,
1226                                 struct serial_icounter_struct *icount)
1227 {
1228         struct serial_state *info = tty->driver_data;
1229         struct async_icount cnow;
1230         unsigned long flags;
1231
1232         local_irq_save(flags);
1233         cnow = info->icount;
1234         local_irq_restore(flags);
1235         icount->cts = cnow.cts;
1236         icount->dsr = cnow.dsr;
1237         icount->rng = cnow.rng;
1238         icount->dcd = cnow.dcd;
1239         icount->rx = cnow.rx;
1240         icount->tx = cnow.tx;
1241         icount->frame = cnow.frame;
1242         icount->overrun = cnow.overrun;
1243         icount->parity = cnow.parity;
1244         icount->brk = cnow.brk;
1245         icount->buf_overrun = cnow.buf_overrun;
1246
1247         return 0;
1248 }
1249
1250 static int rs_ioctl(struct tty_struct *tty,
1251                     unsigned int cmd, unsigned long arg)
1252 {
1253         struct serial_state *info = tty->driver_data;
1254         struct async_icount cprev, cnow;        /* kernel counter temps */
1255         void __user *argp = (void __user *)arg;
1256         unsigned long flags;
1257
1258         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1259                 return -ENODEV;
1260
1261         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1262             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
1263             (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1264                 if (tty->flags & (1 << TTY_IO_ERROR))
1265                     return -EIO;
1266         }
1267
1268         switch (cmd) {
1269                 case TIOCGSERIAL:
1270                         return get_serial_info(tty, info, argp);
1271                 case TIOCSSERIAL:
1272                         return set_serial_info(tty, info, argp);
1273                 case TIOCSERCONFIG:
1274                         return 0;
1275
1276                 case TIOCSERGETLSR: /* Get line status register */
1277                         return get_lsr_info(info, argp);
1278
1279                 case TIOCSERGSTRUCT:
1280                         if (copy_to_user(argp,
1281                                          info, sizeof(struct serial_state)))
1282                                 return -EFAULT;
1283                         return 0;
1284
1285                 /*
1286                  * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1287                  * - mask passed in arg for lines of interest
1288                  *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1289                  * Caller should use TIOCGICOUNT to see which one it was
1290                  */
1291                 case TIOCMIWAIT:
1292                         local_irq_save(flags);
1293                         /* note the counters on entry */
1294                         cprev = info->icount;
1295                         local_irq_restore(flags);
1296                         while (1) {
1297                                 interruptible_sleep_on(&info->tport.delta_msr_wait);
1298                                 /* see if a signal did it */
1299                                 if (signal_pending(current))
1300                                         return -ERESTARTSYS;
1301                                 local_irq_save(flags);
1302                                 cnow = info->icount; /* atomic copy */
1303                                 local_irq_restore(flags);
1304                                 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && 
1305                                     cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1306                                         return -EIO; /* no change => error */
1307                                 if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1308                                      ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1309                                      ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
1310                                      ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1311                                         return 0;
1312                                 }
1313                                 cprev = cnow;
1314                         }
1315                         /* NOTREACHED */
1316
1317                 case TIOCSERGWILD:
1318                 case TIOCSERSWILD:
1319                         /* "setserial -W" is called in Debian boot */
1320                         printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
1321                         return 0;
1322
1323                 default:
1324                         return -ENOIOCTLCMD;
1325                 }
1326         return 0;
1327 }
1328
1329 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
1330 {
1331         struct serial_state *info = tty->driver_data;
1332         unsigned long flags;
1333         unsigned int cflag = tty->termios->c_cflag;
1334
1335         change_speed(tty, info, old_termios);
1336
1337         /* Handle transition to B0 status */
1338         if ((old_termios->c_cflag & CBAUD) &&
1339             !(cflag & CBAUD)) {
1340                 info->MCR &= ~(SER_DTR|SER_RTS);
1341                 local_irq_save(flags);
1342                 rtsdtr_ctrl(info->MCR);
1343                 local_irq_restore(flags);
1344         }
1345
1346         /* Handle transition away from B0 status */
1347         if (!(old_termios->c_cflag & CBAUD) &&
1348             (cflag & CBAUD)) {
1349                 info->MCR |= SER_DTR;
1350                 if (!(tty->termios->c_cflag & CRTSCTS) || 
1351                     !test_bit(TTY_THROTTLED, &tty->flags)) {
1352                         info->MCR |= SER_RTS;
1353                 }
1354                 local_irq_save(flags);
1355                 rtsdtr_ctrl(info->MCR);
1356                 local_irq_restore(flags);
1357         }
1358
1359         /* Handle turning off CRTSCTS */
1360         if ((old_termios->c_cflag & CRTSCTS) &&
1361             !(tty->termios->c_cflag & CRTSCTS)) {
1362                 tty->hw_stopped = 0;
1363                 rs_start(tty);
1364         }
1365
1366 #if 0
1367         /*
1368          * No need to wake up processes in open wait, since they
1369          * sample the CLOCAL flag once, and don't recheck it.
1370          * XXX  It's not clear whether the current behavior is correct
1371          * or not.  Hence, this may change.....
1372          */
1373         if (!(old_termios->c_cflag & CLOCAL) &&
1374             (tty->termios->c_cflag & CLOCAL))
1375                 wake_up_interruptible(&info->open_wait);
1376 #endif
1377 }
1378
1379 /*
1380  * ------------------------------------------------------------
1381  * rs_close()
1382  * 
1383  * This routine is called when the serial port gets closed.  First, we
1384  * wait for the last remaining data to be sent.  Then, we unlink its
1385  * async structure from the interrupt chain if necessary, and we free
1386  * that IRQ if nothing is left in the chain.
1387  * ------------------------------------------------------------
1388  */
1389 static void rs_close(struct tty_struct *tty, struct file * filp)
1390 {
1391         struct serial_state *state = tty->driver_data;
1392         struct tty_port *port = &state->tport;
1393
1394         if (serial_paranoia_check(state, tty->name, "rs_close"))
1395                 return;
1396
1397         if (tty_port_close_start(port, tty, filp) == 0)
1398                 return;
1399
1400         /*
1401          * At this point we stop accepting input.  To do this, we
1402          * disable the receive line status interrupts, and tell the
1403          * interrupt driver to stop checking the data ready bit in the
1404          * line status register.
1405          */
1406         state->read_status_mask &= ~UART_LSR_DR;
1407         if (port->flags & ASYNC_INITIALIZED) {
1408                 /* disable receive interrupts */
1409                 custom.intena = IF_RBF;
1410                 mb();
1411                 /* clear any pending receive interrupt */
1412                 custom.intreq = IF_RBF;
1413                 mb();
1414
1415                 /*
1416                  * Before we drop DTR, make sure the UART transmitter
1417                  * has completely drained; this is especially
1418                  * important if there is a transmit FIFO!
1419                  */
1420                 rs_wait_until_sent(tty, state->timeout);
1421         }
1422         shutdown(tty, state);
1423         rs_flush_buffer(tty);
1424                 
1425         tty_ldisc_flush(tty);
1426         port->tty = NULL;
1427
1428         tty_port_close_end(port, tty);
1429 }
1430
1431 /*
1432  * rs_wait_until_sent() --- wait until the transmitter is empty
1433  */
1434 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1435 {
1436         struct serial_state *info = tty->driver_data;
1437         unsigned long orig_jiffies, char_time;
1438         int lsr;
1439
1440         if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
1441                 return;
1442
1443         if (info->xmit_fifo_size == 0)
1444                 return; /* Just in case.... */
1445
1446         orig_jiffies = jiffies;
1447
1448         /*
1449          * Set the check interval to be 1/5 of the estimated time to
1450          * send a single character, and make it at least 1.  The check
1451          * interval should also be less than the timeout.
1452          * 
1453          * Note: we have to use pretty tight timings here to satisfy
1454          * the NIST-PCTS.
1455          */
1456         char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1457         char_time = char_time / 5;
1458         if (char_time == 0)
1459                 char_time = 1;
1460         if (timeout)
1461           char_time = min_t(unsigned long, char_time, timeout);
1462         /*
1463          * If the transmitter hasn't cleared in twice the approximate
1464          * amount of time to send the entire FIFO, it probably won't
1465          * ever clear.  This assumes the UART isn't doing flow
1466          * control, which is currently the case.  Hence, if it ever
1467          * takes longer than info->timeout, this is probably due to a
1468          * UART bug of some kind.  So, we clamp the timeout parameter at
1469          * 2*info->timeout.
1470          */
1471         if (!timeout || timeout > 2*info->timeout)
1472                 timeout = 2*info->timeout;
1473 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1474         printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
1475         printk("jiff=%lu...", jiffies);
1476 #endif
1477         while(!((lsr = custom.serdatr) & SDR_TSRE)) {
1478 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1479                 printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
1480 #endif
1481                 msleep_interruptible(jiffies_to_msecs(char_time));
1482                 if (signal_pending(current))
1483                         break;
1484                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
1485                         break;
1486         }
1487         __set_current_state(TASK_RUNNING);
1488
1489 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1490         printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1491 #endif
1492 }
1493
1494 /*
1495  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1496  */
1497 static void rs_hangup(struct tty_struct *tty)
1498 {
1499         struct serial_state *info = tty->driver_data;
1500
1501         if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1502                 return;
1503
1504         rs_flush_buffer(tty);
1505         shutdown(tty, info);
1506         info->tport.count = 0;
1507         info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
1508         info->tport.tty = NULL;
1509         wake_up_interruptible(&info->tport.open_wait);
1510 }
1511
1512 /*
1513  * This routine is called whenever a serial port is opened.  It
1514  * enables interrupts for a serial port, linking in its async structure into
1515  * the IRQ chain.   It also performs the serial-specific
1516  * initialization for the tty structure.
1517  */
1518 static int rs_open(struct tty_struct *tty, struct file * filp)
1519 {
1520         struct serial_state *info = rs_table + tty->index;
1521         struct tty_port *port = &info->tport;
1522         int retval;
1523
1524         port->count++;
1525         port->tty = tty;
1526         tty->driver_data = info;
1527         tty->port = port;
1528         if (serial_paranoia_check(info, tty->name, "rs_open"))
1529                 return -ENODEV;
1530
1531         tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1532
1533         retval = startup(tty, info);
1534         if (retval) {
1535                 return retval;
1536         }
1537
1538         return tty_port_block_til_ready(port, tty, filp);
1539 }
1540
1541 /*
1542  * /proc fs routines....
1543  */
1544
1545 static inline void line_info(struct seq_file *m, int line,
1546                 struct serial_state *state)
1547 {
1548         char    stat_buf[30], control, status;
1549         unsigned long flags;
1550
1551         seq_printf(m, "%d: uart:amiga_builtin", line);
1552
1553         local_irq_save(flags);
1554         status = ciab.pra;
1555         control = (state->tport.flags & ASYNC_INITIALIZED) ? state->MCR : status;
1556         local_irq_restore(flags);
1557
1558         stat_buf[0] = 0;
1559         stat_buf[1] = 0;
1560         if(!(control & SER_RTS))
1561                 strcat(stat_buf, "|RTS");
1562         if(!(status & SER_CTS))
1563                 strcat(stat_buf, "|CTS");
1564         if(!(control & SER_DTR))
1565                 strcat(stat_buf, "|DTR");
1566         if(!(status & SER_DSR))
1567                 strcat(stat_buf, "|DSR");
1568         if(!(status & SER_DCD))
1569                 strcat(stat_buf, "|CD");
1570
1571         if (state->quot)
1572                 seq_printf(m, " baud:%d", state->baud_base / state->quot);
1573
1574         seq_printf(m, " tx:%d rx:%d", state->icount.tx, state->icount.rx);
1575
1576         if (state->icount.frame)
1577                 seq_printf(m, " fe:%d", state->icount.frame);
1578
1579         if (state->icount.parity)
1580                 seq_printf(m, " pe:%d", state->icount.parity);
1581
1582         if (state->icount.brk)
1583                 seq_printf(m, " brk:%d", state->icount.brk);
1584
1585         if (state->icount.overrun)
1586                 seq_printf(m, " oe:%d", state->icount.overrun);
1587
1588         /*
1589          * Last thing is the RS-232 status lines
1590          */
1591         seq_printf(m, " %s\n", stat_buf+1);
1592 }
1593
1594 static int rs_proc_show(struct seq_file *m, void *v)
1595 {
1596         seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
1597         line_info(m, 0, &rs_table[0]);
1598         return 0;
1599 }
1600
1601 static int rs_proc_open(struct inode *inode, struct file *file)
1602 {
1603         return single_open(file, rs_proc_show, NULL);
1604 }
1605
1606 static const struct file_operations rs_proc_fops = {
1607         .owner          = THIS_MODULE,
1608         .open           = rs_proc_open,
1609         .read           = seq_read,
1610         .llseek         = seq_lseek,
1611         .release        = single_release,
1612 };
1613
1614 /*
1615  * ---------------------------------------------------------------------
1616  * rs_init() and friends
1617  *
1618  * rs_init() is called at boot-time to initialize the serial driver.
1619  * ---------------------------------------------------------------------
1620  */
1621
1622 /*
1623  * This routine prints out the appropriate serial driver version
1624  * number, and identifies which options were configured into this
1625  * driver.
1626  */
1627 static void show_serial_version(void)
1628 {
1629         printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
1630 }
1631
1632
1633 static const struct tty_operations serial_ops = {
1634         .open = rs_open,
1635         .close = rs_close,
1636         .write = rs_write,
1637         .put_char = rs_put_char,
1638         .flush_chars = rs_flush_chars,
1639         .write_room = rs_write_room,
1640         .chars_in_buffer = rs_chars_in_buffer,
1641         .flush_buffer = rs_flush_buffer,
1642         .ioctl = rs_ioctl,
1643         .throttle = rs_throttle,
1644         .unthrottle = rs_unthrottle,
1645         .set_termios = rs_set_termios,
1646         .stop = rs_stop,
1647         .start = rs_start,
1648         .hangup = rs_hangup,
1649         .break_ctl = rs_break,
1650         .send_xchar = rs_send_xchar,
1651         .wait_until_sent = rs_wait_until_sent,
1652         .tiocmget = rs_tiocmget,
1653         .tiocmset = rs_tiocmset,
1654         .get_icount = rs_get_icount,
1655         .proc_fops = &rs_proc_fops,
1656 };
1657
1658 static int amiga_carrier_raised(struct tty_port *port)
1659 {
1660         return !(ciab.pra & SER_DCD);
1661 }
1662
1663 static void amiga_dtr_rts(struct tty_port *port, int raise)
1664 {
1665         struct serial_state *info = container_of(port, struct serial_state,
1666                         tport);
1667         unsigned long flags;
1668
1669         if (raise)
1670                 info->MCR |= SER_DTR|SER_RTS;
1671         else
1672                 info->MCR &= ~(SER_DTR|SER_RTS);
1673
1674         local_irq_save(flags);
1675         rtsdtr_ctrl(info->MCR);
1676         local_irq_restore(flags);
1677 }
1678
1679 static const struct tty_port_operations amiga_port_ops = {
1680         .carrier_raised = amiga_carrier_raised,
1681         .dtr_rts = amiga_dtr_rts,
1682 };
1683
1684 /*
1685  * The serial driver boot-time initialization code!
1686  */
1687 static int __init amiga_serial_probe(struct platform_device *pdev)
1688 {
1689         unsigned long flags;
1690         struct serial_state * state;
1691         int error;
1692
1693         serial_driver = alloc_tty_driver(NR_PORTS);
1694         if (!serial_driver)
1695                 return -ENOMEM;
1696
1697         show_serial_version();
1698
1699         /* Initialize the tty_driver structure */
1700
1701         serial_driver->driver_name = "amiserial";
1702         serial_driver->name = "ttyS";
1703         serial_driver->major = TTY_MAJOR;
1704         serial_driver->minor_start = 64;
1705         serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1706         serial_driver->subtype = SERIAL_TYPE_NORMAL;
1707         serial_driver->init_termios = tty_std_termios;
1708         serial_driver->init_termios.c_cflag =
1709                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1710         serial_driver->flags = TTY_DRIVER_REAL_RAW;
1711         tty_set_operations(serial_driver, &serial_ops);
1712
1713         error = tty_register_driver(serial_driver);
1714         if (error)
1715                 goto fail_put_tty_driver;
1716
1717         state = rs_table;
1718         state->port = (int)&custom.serdatr; /* Just to give it a value */
1719         state->custom_divisor = 0;
1720         state->icount.cts = state->icount.dsr = 
1721           state->icount.rng = state->icount.dcd = 0;
1722         state->icount.rx = state->icount.tx = 0;
1723         state->icount.frame = state->icount.parity = 0;
1724         state->icount.overrun = state->icount.brk = 0;
1725         tty_port_init(&state->tport);
1726         state->tport.ops = &amiga_port_ops;
1727
1728         printk(KERN_INFO "ttyS0 is the amiga builtin serial port\n");
1729
1730         /* Hardware set up */
1731
1732         state->baud_base = amiga_colorclock;
1733         state->xmit_fifo_size = 1;
1734
1735         /* set ISRs, and then disable the rx interrupts */
1736         error = request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
1737         if (error)
1738                 goto fail_unregister;
1739
1740         error = request_irq(IRQ_AMIGA_RBF, ser_rx_int, 0,
1741                             "serial RX", state);
1742         if (error)
1743                 goto fail_free_irq;
1744
1745         local_irq_save(flags);
1746
1747         /* turn off Rx and Tx interrupts */
1748         custom.intena = IF_RBF | IF_TBE;
1749         mb();
1750
1751         /* clear any pending interrupt */
1752         custom.intreq = IF_RBF | IF_TBE;
1753         mb();
1754
1755         local_irq_restore(flags);
1756
1757         /*
1758          * set the appropriate directions for the modem control flags,
1759          * and clear RTS and DTR
1760          */
1761         ciab.ddra |= (SER_DTR | SER_RTS);   /* outputs */
1762         ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR);  /* inputs */
1763
1764         platform_set_drvdata(pdev, state);
1765
1766         return 0;
1767
1768 fail_free_irq:
1769         free_irq(IRQ_AMIGA_TBE, state);
1770 fail_unregister:
1771         tty_unregister_driver(serial_driver);
1772 fail_put_tty_driver:
1773         put_tty_driver(serial_driver);
1774         return error;
1775 }
1776
1777 static int __exit amiga_serial_remove(struct platform_device *pdev)
1778 {
1779         int error;
1780         struct serial_state *state = platform_get_drvdata(pdev);
1781
1782         /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
1783         if ((error = tty_unregister_driver(serial_driver)))
1784                 printk("SERIAL: failed to unregister serial driver (%d)\n",
1785                        error);
1786         put_tty_driver(serial_driver);
1787
1788         free_irq(IRQ_AMIGA_TBE, state);
1789         free_irq(IRQ_AMIGA_RBF, state);
1790
1791         platform_set_drvdata(pdev, NULL);
1792
1793         return error;
1794 }
1795
1796 static struct platform_driver amiga_serial_driver = {
1797         .remove = __exit_p(amiga_serial_remove),
1798         .driver   = {
1799                 .name   = "amiga-serial",
1800                 .owner  = THIS_MODULE,
1801         },
1802 };
1803
1804 static int __init amiga_serial_init(void)
1805 {
1806         return platform_driver_probe(&amiga_serial_driver, amiga_serial_probe);
1807 }
1808
1809 module_init(amiga_serial_init);
1810
1811 static void __exit amiga_serial_exit(void)
1812 {
1813         platform_driver_unregister(&amiga_serial_driver);
1814 }
1815
1816 module_exit(amiga_serial_exit);
1817
1818
1819 #if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE)
1820
1821 /*
1822  * ------------------------------------------------------------
1823  * Serial console driver
1824  * ------------------------------------------------------------
1825  */
1826
1827 static void amiga_serial_putc(char c)
1828 {
1829         custom.serdat = (unsigned char)c | 0x100;
1830         while (!(custom.serdatr & 0x2000))
1831                 barrier();
1832 }
1833
1834 /*
1835  *      Print a string to the serial port trying not to disturb
1836  *      any possible real use of the port...
1837  *
1838  *      The console must be locked when we get here.
1839  */
1840 static void serial_console_write(struct console *co, const char *s,
1841                                 unsigned count)
1842 {
1843         unsigned short intena = custom.intenar;
1844
1845         custom.intena = IF_TBE;
1846
1847         while (count--) {
1848                 if (*s == '\n')
1849                         amiga_serial_putc('\r');
1850                 amiga_serial_putc(*s++);
1851         }
1852
1853         custom.intena = IF_SETCLR | (intena & IF_TBE);
1854 }
1855
1856 static struct tty_driver *serial_console_device(struct console *c, int *index)
1857 {
1858         *index = 0;
1859         return serial_driver;
1860 }
1861
1862 static struct console sercons = {
1863         .name =         "ttyS",
1864         .write =        serial_console_write,
1865         .device =       serial_console_device,
1866         .flags =        CON_PRINTBUFFER,
1867         .index =        -1,
1868 };
1869
1870 /*
1871  *      Register console.
1872  */
1873 static int __init amiserial_console_init(void)
1874 {
1875         register_console(&sercons);
1876         return 0;
1877 }
1878 console_initcall(amiserial_console_init);
1879
1880 #endif /* CONFIG_SERIAL_CONSOLE && !MODULE */
1881
1882 MODULE_LICENSE("GPL");
1883 MODULE_ALIAS("platform:amiga-serial");