ia64/linux-2.6.18-xen.hg

view drivers/char/amiserial.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
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 */
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 */
34 #include <linux/delay.h>
36 #undef SERIAL_PARANOIA_CHECK
37 #define SERIAL_DO_RESTART
39 /* Set of debugging defines */
41 #undef SERIAL_DEBUG_INTR
42 #undef SERIAL_DEBUG_OPEN
43 #undef SERIAL_DEBUG_FLOW
44 #undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
46 /* Sanity checks */
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
55 /*
56 * End of serial driver configuration section.
57 */
59 #include <linux/module.h>
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";
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>
86 #include <asm/setup.h>
88 #include <asm/system.h>
90 #include <asm/irq.h>
92 #include <asm/amigahw.h>
93 #include <asm/amigaints.h>
95 #define custom amiga_custom
96 static char *serial_name = "Amiga-builtin serial driver";
98 static struct tty_driver *serial_driver;
100 /* number of characters left in xmit buffer before we ask for more */
101 #define WAKEUP_CHARS 256
103 static struct async_struct *IRQ_ports;
105 static unsigned char current_ctl_bits;
107 static void change_speed(struct async_struct *info, struct termios *old);
108 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
111 static struct serial_state rs_table[1];
113 #define NR_PORTS ARRAY_SIZE(rs_table)
115 /*
116 * tmp_buf is used as a temporary buffer by serial_write. We need to
117 * lock it in case the copy_from_user blocks while swapping in a page,
118 * and some other program tries to do a serial write at the same time.
119 * Since the lock will only come under contention when the system is
120 * swapping and available memory is low, it makes sense to share one
121 * buffer across all the serial ports, since it significantly saves
122 * memory if large numbers of serial ports are open.
123 */
124 static unsigned char *tmp_buf;
126 #include <asm/uaccess.h>
128 #define serial_isroot() (capable(CAP_SYS_ADMIN))
131 static inline int serial_paranoia_check(struct async_struct *info,
132 char *name, const char *routine)
133 {
134 #ifdef SERIAL_PARANOIA_CHECK
135 static const char *badmagic =
136 "Warning: bad magic number for serial struct (%s) in %s\n";
137 static const char *badinfo =
138 "Warning: null async_struct for (%s) in %s\n";
140 if (!info) {
141 printk(badinfo, name, routine);
142 return 1;
143 }
144 if (info->magic != SERIAL_MAGIC) {
145 printk(badmagic, name, routine);
146 return 1;
147 }
148 #endif
149 return 0;
150 }
152 /* some serial hardware definitions */
153 #define SDR_OVRUN (1<<15)
154 #define SDR_RBF (1<<14)
155 #define SDR_TBE (1<<13)
156 #define SDR_TSRE (1<<12)
158 #define SERPER_PARENB (1<<15)
160 #define AC_SETCLR (1<<15)
161 #define AC_UARTBRK (1<<11)
163 #define SER_DTR (1<<7)
164 #define SER_RTS (1<<6)
165 #define SER_DCD (1<<5)
166 #define SER_CTS (1<<4)
167 #define SER_DSR (1<<3)
169 static __inline__ void rtsdtr_ctrl(int bits)
170 {
171 ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
172 }
174 /*
175 * ------------------------------------------------------------
176 * rs_stop() and rs_start()
177 *
178 * This routines are called before setting or resetting tty->stopped.
179 * They enable or disable transmitter interrupts, as necessary.
180 * ------------------------------------------------------------
181 */
182 static void rs_stop(struct tty_struct *tty)
183 {
184 struct async_struct *info = (struct async_struct *)tty->driver_data;
185 unsigned long flags;
187 if (serial_paranoia_check(info, tty->name, "rs_stop"))
188 return;
190 local_irq_save(flags);
191 if (info->IER & UART_IER_THRI) {
192 info->IER &= ~UART_IER_THRI;
193 /* disable Tx interrupt and remove any pending interrupts */
194 custom.intena = IF_TBE;
195 mb();
196 custom.intreq = IF_TBE;
197 mb();
198 }
199 local_irq_restore(flags);
200 }
202 static void rs_start(struct tty_struct *tty)
203 {
204 struct async_struct *info = (struct async_struct *)tty->driver_data;
205 unsigned long flags;
207 if (serial_paranoia_check(info, tty->name, "rs_start"))
208 return;
210 local_irq_save(flags);
211 if (info->xmit.head != info->xmit.tail
212 && info->xmit.buf
213 && !(info->IER & UART_IER_THRI)) {
214 info->IER |= UART_IER_THRI;
215 custom.intena = IF_SETCLR | IF_TBE;
216 mb();
217 /* set a pending Tx Interrupt, transmitter should restart now */
218 custom.intreq = IF_SETCLR | IF_TBE;
219 mb();
220 }
221 local_irq_restore(flags);
222 }
224 /*
225 * ----------------------------------------------------------------------
226 *
227 * Here starts the interrupt handling routines. All of the following
228 * subroutines are declared as inline and are folded into
229 * rs_interrupt(). They were separated out for readability's sake.
230 *
231 * Note: rs_interrupt() is a "fast" interrupt, which means that it
232 * runs with interrupts turned off. People who may want to modify
233 * rs_interrupt() should try to keep the interrupt handler as fast as
234 * possible. After you are done making modifications, it is not a bad
235 * idea to do:
236 *
237 * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
238 *
239 * and look at the resulting assemble code in serial.s.
240 *
241 * - Ted Ts'o (tytso@mit.edu), 7-Mar-93
242 * -----------------------------------------------------------------------
243 */
245 /*
246 * This routine is used by the interrupt handler to schedule
247 * processing in the software interrupt portion of the driver.
248 */
249 static void rs_sched_event(struct async_struct *info,
250 int event)
251 {
252 info->event |= 1 << event;
253 tasklet_schedule(&info->tlet);
254 }
256 static void receive_chars(struct async_struct *info)
257 {
258 int status;
259 int serdatr;
260 struct tty_struct *tty = info->tty;
261 unsigned char ch, flag;
262 struct async_icount *icount;
263 int oe = 0;
265 icount = &info->state->icount;
267 status = UART_LSR_DR; /* We obviously have a character! */
268 serdatr = custom.serdatr;
269 mb();
270 custom.intreq = IF_RBF;
271 mb();
273 if((serdatr & 0x1ff) == 0)
274 status |= UART_LSR_BI;
275 if(serdatr & SDR_OVRUN)
276 status |= UART_LSR_OE;
278 ch = serdatr & 0xff;
279 icount->rx++;
281 #ifdef SERIAL_DEBUG_INTR
282 printk("DR%02x:%02x...", ch, status);
283 #endif
284 flag = TTY_NORMAL;
286 /*
287 * We don't handle parity or frame errors - but I have left
288 * the code in, since I'm not sure that the errors can't be
289 * detected.
290 */
292 if (status & (UART_LSR_BI | UART_LSR_PE |
293 UART_LSR_FE | UART_LSR_OE)) {
294 /*
295 * For statistics only
296 */
297 if (status & UART_LSR_BI) {
298 status &= ~(UART_LSR_FE | UART_LSR_PE);
299 icount->brk++;
300 } else if (status & UART_LSR_PE)
301 icount->parity++;
302 else if (status & UART_LSR_FE)
303 icount->frame++;
304 if (status & UART_LSR_OE)
305 icount->overrun++;
307 /*
308 * Now check to see if character should be
309 * ignored, and mask off conditions which
310 * should be ignored.
311 */
312 if (status & info->ignore_status_mask)
313 goto out;
315 status &= info->read_status_mask;
317 if (status & (UART_LSR_BI)) {
318 #ifdef SERIAL_DEBUG_INTR
319 printk("handling break....");
320 #endif
321 flag = TTY_BREAK;
322 if (info->flags & ASYNC_SAK)
323 do_SAK(tty);
324 } else if (status & UART_LSR_PE)
325 flag = TTY_PARITY;
326 else if (status & UART_LSR_FE)
327 flag = TTY_FRAME;
328 if (status & UART_LSR_OE) {
329 /*
330 * Overrun is special, since it's
331 * reported immediately, and doesn't
332 * affect the current character
333 */
334 oe = 1;
335 }
336 }
337 tty_insert_flip_char(tty, ch, flag);
338 if (oe == 1)
339 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
340 tty_flip_buffer_push(tty);
341 out:
342 return;
343 }
345 static void transmit_chars(struct async_struct *info)
346 {
347 custom.intreq = IF_TBE;
348 mb();
349 if (info->x_char) {
350 custom.serdat = info->x_char | 0x100;
351 mb();
352 info->state->icount.tx++;
353 info->x_char = 0;
354 return;
355 }
356 if (info->xmit.head == info->xmit.tail
357 || info->tty->stopped
358 || info->tty->hw_stopped) {
359 info->IER &= ~UART_IER_THRI;
360 custom.intena = IF_TBE;
361 mb();
362 return;
363 }
365 custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
366 mb();
367 info->xmit.tail = info->xmit.tail & (SERIAL_XMIT_SIZE-1);
368 info->state->icount.tx++;
370 if (CIRC_CNT(info->xmit.head,
371 info->xmit.tail,
372 SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
373 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
375 #ifdef SERIAL_DEBUG_INTR
376 printk("THRE...");
377 #endif
378 if (info->xmit.head == info->xmit.tail) {
379 custom.intena = IF_TBE;
380 mb();
381 info->IER &= ~UART_IER_THRI;
382 }
383 }
385 static void check_modem_status(struct async_struct *info)
386 {
387 unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
388 unsigned char dstatus;
389 struct async_icount *icount;
391 /* Determine bits that have changed */
392 dstatus = status ^ current_ctl_bits;
393 current_ctl_bits = status;
395 if (dstatus) {
396 icount = &info->state->icount;
397 /* update input line counters */
398 if (dstatus & SER_DSR)
399 icount->dsr++;
400 if (dstatus & SER_DCD) {
401 icount->dcd++;
402 #ifdef CONFIG_HARD_PPS
403 if ((info->flags & ASYNC_HARDPPS_CD) &&
404 !(status & SER_DCD))
405 hardpps();
406 #endif
407 }
408 if (dstatus & SER_CTS)
409 icount->cts++;
410 wake_up_interruptible(&info->delta_msr_wait);
411 }
413 if ((info->flags & ASYNC_CHECK_CD) && (dstatus & SER_DCD)) {
414 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
415 printk("ttyS%d CD now %s...", info->line,
416 (!(status & SER_DCD)) ? "on" : "off");
417 #endif
418 if (!(status & SER_DCD))
419 wake_up_interruptible(&info->open_wait);
420 else {
421 #ifdef SERIAL_DEBUG_OPEN
422 printk("doing serial hangup...");
423 #endif
424 if (info->tty)
425 tty_hangup(info->tty);
426 }
427 }
428 if (info->flags & ASYNC_CTS_FLOW) {
429 if (info->tty->hw_stopped) {
430 if (!(status & SER_CTS)) {
431 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
432 printk("CTS tx start...");
433 #endif
434 info->tty->hw_stopped = 0;
435 info->IER |= UART_IER_THRI;
436 custom.intena = IF_SETCLR | IF_TBE;
437 mb();
438 /* set a pending Tx Interrupt, transmitter should restart now */
439 custom.intreq = IF_SETCLR | IF_TBE;
440 mb();
441 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
442 return;
443 }
444 } else {
445 if ((status & SER_CTS)) {
446 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
447 printk("CTS tx stop...");
448 #endif
449 info->tty->hw_stopped = 1;
450 info->IER &= ~UART_IER_THRI;
451 /* disable Tx interrupt and remove any pending interrupts */
452 custom.intena = IF_TBE;
453 mb();
454 custom.intreq = IF_TBE;
455 mb();
456 }
457 }
458 }
459 }
461 static irqreturn_t ser_vbl_int( int irq, void *data, struct pt_regs *regs)
462 {
463 /* vbl is just a periodic interrupt we tie into to update modem status */
464 struct async_struct * info = IRQ_ports;
465 /*
466 * TBD - is it better to unregister from this interrupt or to
467 * ignore it if MSI is clear ?
468 */
469 if(info->IER & UART_IER_MSI)
470 check_modem_status(info);
471 return IRQ_HANDLED;
472 }
474 static irqreturn_t ser_rx_int(int irq, void *dev_id, struct pt_regs * regs)
475 {
476 struct async_struct * info;
478 #ifdef SERIAL_DEBUG_INTR
479 printk("ser_rx_int...");
480 #endif
482 info = IRQ_ports;
483 if (!info || !info->tty)
484 return IRQ_NONE;
486 receive_chars(info);
487 info->last_active = jiffies;
488 #ifdef SERIAL_DEBUG_INTR
489 printk("end.\n");
490 #endif
491 return IRQ_HANDLED;
492 }
494 static irqreturn_t ser_tx_int(int irq, void *dev_id, struct pt_regs * regs)
495 {
496 struct async_struct * info;
498 if (custom.serdatr & SDR_TBE) {
499 #ifdef SERIAL_DEBUG_INTR
500 printk("ser_tx_int...");
501 #endif
503 info = IRQ_ports;
504 if (!info || !info->tty)
505 return IRQ_NONE;
507 transmit_chars(info);
508 info->last_active = jiffies;
509 #ifdef SERIAL_DEBUG_INTR
510 printk("end.\n");
511 #endif
512 }
513 return IRQ_HANDLED;
514 }
516 /*
517 * -------------------------------------------------------------------
518 * Here ends the serial interrupt routines.
519 * -------------------------------------------------------------------
520 */
522 /*
523 * This routine is used to handle the "bottom half" processing for the
524 * serial driver, known also the "software interrupt" processing.
525 * This processing is done at the kernel interrupt level, after the
526 * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON. This
527 * is where time-consuming activities which can not be done in the
528 * interrupt driver proper are done; the interrupt driver schedules
529 * them using rs_sched_event(), and they get done here.
530 */
532 static void do_softint(unsigned long private_)
533 {
534 struct async_struct *info = (struct async_struct *) private_;
535 struct tty_struct *tty;
537 tty = info->tty;
538 if (!tty)
539 return;
541 if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
542 tty_wakeup(tty);
543 wake_up_interruptible(&tty->write_wait);
544 }
545 }
547 /*
548 * ---------------------------------------------------------------
549 * Low level utility subroutines for the serial driver: routines to
550 * figure out the appropriate timeout for an interrupt chain, routines
551 * to initialize and startup a serial port, and routines to shutdown a
552 * serial port. Useful stuff like that.
553 * ---------------------------------------------------------------
554 */
556 static int startup(struct async_struct * info)
557 {
558 unsigned long flags;
559 int retval=0;
560 unsigned long page;
562 page = get_zeroed_page(GFP_KERNEL);
563 if (!page)
564 return -ENOMEM;
566 local_irq_save(flags);
568 if (info->flags & ASYNC_INITIALIZED) {
569 free_page(page);
570 goto errout;
571 }
573 if (info->xmit.buf)
574 free_page(page);
575 else
576 info->xmit.buf = (unsigned char *) page;
578 #ifdef SERIAL_DEBUG_OPEN
579 printk("starting up ttys%d ...", info->line);
580 #endif
582 /* Clear anything in the input buffer */
584 custom.intreq = IF_RBF;
585 mb();
587 retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
588 if (retval) {
589 if (serial_isroot()) {
590 if (info->tty)
591 set_bit(TTY_IO_ERROR,
592 &info->tty->flags);
593 retval = 0;
594 }
595 goto errout;
596 }
598 /* enable both Rx and Tx interrupts */
599 custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
600 mb();
601 info->IER = UART_IER_MSI;
603 /* remember current state of the DCD and CTS bits */
604 current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
606 IRQ_ports = info;
608 info->MCR = 0;
609 if (info->tty->termios->c_cflag & CBAUD)
610 info->MCR = SER_DTR | SER_RTS;
611 rtsdtr_ctrl(info->MCR);
613 if (info->tty)
614 clear_bit(TTY_IO_ERROR, &info->tty->flags);
615 info->xmit.head = info->xmit.tail = 0;
617 /*
618 * Set up the tty->alt_speed kludge
619 */
620 if (info->tty) {
621 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
622 info->tty->alt_speed = 57600;
623 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
624 info->tty->alt_speed = 115200;
625 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
626 info->tty->alt_speed = 230400;
627 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
628 info->tty->alt_speed = 460800;
629 }
631 /*
632 * and set the speed of the serial port
633 */
634 change_speed(info, NULL);
636 info->flags |= ASYNC_INITIALIZED;
637 local_irq_restore(flags);
638 return 0;
640 errout:
641 local_irq_restore(flags);
642 return retval;
643 }
645 /*
646 * This routine will shutdown a serial port; interrupts are disabled, and
647 * DTR is dropped if the hangup on close termio flag is on.
648 */
649 static void shutdown(struct async_struct * info)
650 {
651 unsigned long flags;
652 struct serial_state *state;
654 if (!(info->flags & ASYNC_INITIALIZED))
655 return;
657 state = info->state;
659 #ifdef SERIAL_DEBUG_OPEN
660 printk("Shutting down serial port %d ....\n", info->line);
661 #endif
663 local_irq_save(flags); /* Disable interrupts */
665 /*
666 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
667 * here so the queue might never be waken up
668 */
669 wake_up_interruptible(&info->delta_msr_wait);
671 IRQ_ports = NULL;
673 /*
674 * Free the IRQ, if necessary
675 */
676 free_irq(IRQ_AMIGA_VERTB, info);
678 if (info->xmit.buf) {
679 free_page((unsigned long) info->xmit.buf);
680 info->xmit.buf = NULL;
681 }
683 info->IER = 0;
684 custom.intena = IF_RBF | IF_TBE;
685 mb();
687 /* disable break condition */
688 custom.adkcon = AC_UARTBRK;
689 mb();
691 if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
692 info->MCR &= ~(SER_DTR|SER_RTS);
693 rtsdtr_ctrl(info->MCR);
695 if (info->tty)
696 set_bit(TTY_IO_ERROR, &info->tty->flags);
698 info->flags &= ~ASYNC_INITIALIZED;
699 local_irq_restore(flags);
700 }
703 /*
704 * This routine is called to set the UART divisor registers to match
705 * the specified baud rate for a serial port.
706 */
707 static void change_speed(struct async_struct *info,
708 struct termios *old_termios)
709 {
710 int quot = 0, baud_base, baud;
711 unsigned cflag, cval = 0;
712 int bits;
713 unsigned long flags;
715 if (!info->tty || !info->tty->termios)
716 return;
717 cflag = info->tty->termios->c_cflag;
719 /* Byte size is always 8 bits plus parity bit if requested */
721 cval = 3; bits = 10;
722 if (cflag & CSTOPB) {
723 cval |= 0x04;
724 bits++;
725 }
726 if (cflag & PARENB) {
727 cval |= UART_LCR_PARITY;
728 bits++;
729 }
730 if (!(cflag & PARODD))
731 cval |= UART_LCR_EPAR;
732 #ifdef CMSPAR
733 if (cflag & CMSPAR)
734 cval |= UART_LCR_SPAR;
735 #endif
737 /* Determine divisor based on baud rate */
738 baud = tty_get_baud_rate(info->tty);
739 if (!baud)
740 baud = 9600; /* B0 transition handled in rs_set_termios */
741 baud_base = info->state->baud_base;
742 if (baud == 38400 &&
743 ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
744 quot = info->state->custom_divisor;
745 else {
746 if (baud == 134)
747 /* Special case since 134 is really 134.5 */
748 quot = (2*baud_base / 269);
749 else if (baud)
750 quot = baud_base / baud;
751 }
752 /* If the quotient is zero refuse the change */
753 if (!quot && old_termios) {
754 info->tty->termios->c_cflag &= ~CBAUD;
755 info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
756 baud = tty_get_baud_rate(info->tty);
757 if (!baud)
758 baud = 9600;
759 if (baud == 38400 &&
760 ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
761 quot = info->state->custom_divisor;
762 else {
763 if (baud == 134)
764 /* Special case since 134 is really 134.5 */
765 quot = (2*baud_base / 269);
766 else if (baud)
767 quot = baud_base / baud;
768 }
769 }
770 /* As a last resort, if the quotient is zero, default to 9600 bps */
771 if (!quot)
772 quot = baud_base / 9600;
773 info->quot = quot;
774 info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
775 info->timeout += HZ/50; /* Add .02 seconds of slop */
777 /* CTS flow control flag and modem status interrupts */
778 info->IER &= ~UART_IER_MSI;
779 if (info->flags & ASYNC_HARDPPS_CD)
780 info->IER |= UART_IER_MSI;
781 if (cflag & CRTSCTS) {
782 info->flags |= ASYNC_CTS_FLOW;
783 info->IER |= UART_IER_MSI;
784 } else
785 info->flags &= ~ASYNC_CTS_FLOW;
786 if (cflag & CLOCAL)
787 info->flags &= ~ASYNC_CHECK_CD;
788 else {
789 info->flags |= ASYNC_CHECK_CD;
790 info->IER |= UART_IER_MSI;
791 }
792 /* TBD:
793 * Does clearing IER_MSI imply that we should disbale the VBL interrupt ?
794 */
796 /*
797 * Set up parity check flag
798 */
799 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
801 info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
802 if (I_INPCK(info->tty))
803 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
804 if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
805 info->read_status_mask |= UART_LSR_BI;
807 /*
808 * Characters to ignore
809 */
810 info->ignore_status_mask = 0;
811 if (I_IGNPAR(info->tty))
812 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
813 if (I_IGNBRK(info->tty)) {
814 info->ignore_status_mask |= UART_LSR_BI;
815 /*
816 * If we're ignore parity and break indicators, ignore
817 * overruns too. (For real raw support).
818 */
819 if (I_IGNPAR(info->tty))
820 info->ignore_status_mask |= UART_LSR_OE;
821 }
822 /*
823 * !!! ignore all characters if CREAD is not set
824 */
825 if ((cflag & CREAD) == 0)
826 info->ignore_status_mask |= UART_LSR_DR;
827 local_irq_save(flags);
829 {
830 short serper;
832 /* Set up the baud rate */
833 serper = quot - 1;
835 /* Enable or disable parity bit */
837 if(cval & UART_LCR_PARITY)
838 serper |= (SERPER_PARENB);
840 custom.serper = serper;
841 mb();
842 }
844 info->LCR = cval; /* Save LCR */
845 local_irq_restore(flags);
846 }
848 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
849 {
850 struct async_struct *info;
851 unsigned long flags;
853 if (!tty)
854 return;
856 info = tty->driver_data;
858 if (serial_paranoia_check(info, tty->name, "rs_put_char"))
859 return;
861 if (!info->xmit.buf)
862 return;
864 local_irq_save(flags);
865 if (CIRC_SPACE(info->xmit.head,
866 info->xmit.tail,
867 SERIAL_XMIT_SIZE) == 0) {
868 local_irq_restore(flags);
869 return;
870 }
872 info->xmit.buf[info->xmit.head++] = ch;
873 info->xmit.head &= SERIAL_XMIT_SIZE-1;
874 local_irq_restore(flags);
875 }
877 static void rs_flush_chars(struct tty_struct *tty)
878 {
879 struct async_struct *info = (struct async_struct *)tty->driver_data;
880 unsigned long flags;
882 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
883 return;
885 if (info->xmit.head == info->xmit.tail
886 || tty->stopped
887 || tty->hw_stopped
888 || !info->xmit.buf)
889 return;
891 local_irq_save(flags);
892 info->IER |= UART_IER_THRI;
893 custom.intena = IF_SETCLR | IF_TBE;
894 mb();
895 /* set a pending Tx Interrupt, transmitter should restart now */
896 custom.intreq = IF_SETCLR | IF_TBE;
897 mb();
898 local_irq_restore(flags);
899 }
901 static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
902 {
903 int c, ret = 0;
904 struct async_struct *info;
905 unsigned long flags;
907 if (!tty)
908 return 0;
910 info = tty->driver_data;
912 if (serial_paranoia_check(info, tty->name, "rs_write"))
913 return 0;
915 if (!info->xmit.buf || !tmp_buf)
916 return 0;
918 local_save_flags(flags);
919 local_irq_disable();
920 while (1) {
921 c = CIRC_SPACE_TO_END(info->xmit.head,
922 info->xmit.tail,
923 SERIAL_XMIT_SIZE);
924 if (count < c)
925 c = count;
926 if (c <= 0) {
927 break;
928 }
929 memcpy(info->xmit.buf + info->xmit.head, buf, c);
930 info->xmit.head = ((info->xmit.head + c) &
931 (SERIAL_XMIT_SIZE-1));
932 buf += c;
933 count -= c;
934 ret += c;
935 }
936 local_irq_restore(flags);
938 if (info->xmit.head != info->xmit.tail
939 && !tty->stopped
940 && !tty->hw_stopped
941 && !(info->IER & UART_IER_THRI)) {
942 info->IER |= UART_IER_THRI;
943 local_irq_disable();
944 custom.intena = IF_SETCLR | IF_TBE;
945 mb();
946 /* set a pending Tx Interrupt, transmitter should restart now */
947 custom.intreq = IF_SETCLR | IF_TBE;
948 mb();
949 local_irq_restore(flags);
950 }
951 return ret;
952 }
954 static int rs_write_room(struct tty_struct *tty)
955 {
956 struct async_struct *info = (struct async_struct *)tty->driver_data;
958 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
959 return 0;
960 return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
961 }
963 static int rs_chars_in_buffer(struct tty_struct *tty)
964 {
965 struct async_struct *info = (struct async_struct *)tty->driver_data;
967 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
968 return 0;
969 return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
970 }
972 static void rs_flush_buffer(struct tty_struct *tty)
973 {
974 struct async_struct *info = (struct async_struct *)tty->driver_data;
975 unsigned long flags;
977 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
978 return;
979 local_irq_save(flags);
980 info->xmit.head = info->xmit.tail = 0;
981 local_irq_restore(flags);
982 wake_up_interruptible(&tty->write_wait);
983 tty_wakeup(tty);
984 }
986 /*
987 * This function is used to send a high-priority XON/XOFF character to
988 * the device
989 */
990 static void rs_send_xchar(struct tty_struct *tty, char ch)
991 {
992 struct async_struct *info = (struct async_struct *)tty->driver_data;
993 unsigned long flags;
995 if (serial_paranoia_check(info, tty->name, "rs_send_char"))
996 return;
998 info->x_char = ch;
999 if (ch) {
1000 /* Make sure transmit interrupts are on */
1002 /* Check this ! */
1003 local_irq_save(flags);
1004 if(!(custom.intenar & IF_TBE)) {
1005 custom.intena = IF_SETCLR | IF_TBE;
1006 mb();
1007 /* set a pending Tx Interrupt, transmitter should restart now */
1008 custom.intreq = IF_SETCLR | IF_TBE;
1009 mb();
1011 local_irq_restore(flags);
1013 info->IER |= UART_IER_THRI;
1017 /*
1018 * ------------------------------------------------------------
1019 * rs_throttle()
1021 * This routine is called by the upper-layer tty layer to signal that
1022 * incoming characters should be throttled.
1023 * ------------------------------------------------------------
1024 */
1025 static void rs_throttle(struct tty_struct * tty)
1027 struct async_struct *info = (struct async_struct *)tty->driver_data;
1028 unsigned long flags;
1029 #ifdef SERIAL_DEBUG_THROTTLE
1030 char buf[64];
1032 printk("throttle %s: %d....\n", tty_name(tty, buf),
1033 tty->ldisc.chars_in_buffer(tty));
1034 #endif
1036 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
1037 return;
1039 if (I_IXOFF(tty))
1040 rs_send_xchar(tty, STOP_CHAR(tty));
1042 if (tty->termios->c_cflag & CRTSCTS)
1043 info->MCR &= ~SER_RTS;
1045 local_irq_save(flags);
1046 rtsdtr_ctrl(info->MCR);
1047 local_irq_restore(flags);
1050 static void rs_unthrottle(struct tty_struct * tty)
1052 struct async_struct *info = (struct async_struct *)tty->driver_data;
1053 unsigned long flags;
1054 #ifdef SERIAL_DEBUG_THROTTLE
1055 char buf[64];
1057 printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1058 tty->ldisc.chars_in_buffer(tty));
1059 #endif
1061 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1062 return;
1064 if (I_IXOFF(tty)) {
1065 if (info->x_char)
1066 info->x_char = 0;
1067 else
1068 rs_send_xchar(tty, START_CHAR(tty));
1070 if (tty->termios->c_cflag & CRTSCTS)
1071 info->MCR |= SER_RTS;
1072 local_irq_save(flags);
1073 rtsdtr_ctrl(info->MCR);
1074 local_irq_restore(flags);
1077 /*
1078 * ------------------------------------------------------------
1079 * rs_ioctl() and friends
1080 * ------------------------------------------------------------
1081 */
1083 static int get_serial_info(struct async_struct * info,
1084 struct serial_struct __user * retinfo)
1086 struct serial_struct tmp;
1087 struct serial_state *state = info->state;
1089 if (!retinfo)
1090 return -EFAULT;
1091 memset(&tmp, 0, sizeof(tmp));
1092 tmp.type = state->type;
1093 tmp.line = state->line;
1094 tmp.port = state->port;
1095 tmp.irq = state->irq;
1096 tmp.flags = state->flags;
1097 tmp.xmit_fifo_size = state->xmit_fifo_size;
1098 tmp.baud_base = state->baud_base;
1099 tmp.close_delay = state->close_delay;
1100 tmp.closing_wait = state->closing_wait;
1101 tmp.custom_divisor = state->custom_divisor;
1102 if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1103 return -EFAULT;
1104 return 0;
1107 static int set_serial_info(struct async_struct * info,
1108 struct serial_struct __user * new_info)
1110 struct serial_struct new_serial;
1111 struct serial_state old_state, *state;
1112 unsigned int change_irq,change_port;
1113 int retval = 0;
1115 if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1116 return -EFAULT;
1117 state = info->state;
1118 old_state = *state;
1120 change_irq = new_serial.irq != state->irq;
1121 change_port = (new_serial.port != state->port);
1122 if(change_irq || change_port || (new_serial.xmit_fifo_size != state->xmit_fifo_size))
1123 return -EINVAL;
1125 if (!serial_isroot()) {
1126 if ((new_serial.baud_base != state->baud_base) ||
1127 (new_serial.close_delay != state->close_delay) ||
1128 (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
1129 ((new_serial.flags & ~ASYNC_USR_MASK) !=
1130 (state->flags & ~ASYNC_USR_MASK)))
1131 return -EPERM;
1132 state->flags = ((state->flags & ~ASYNC_USR_MASK) |
1133 (new_serial.flags & ASYNC_USR_MASK));
1134 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
1135 (new_serial.flags & ASYNC_USR_MASK));
1136 state->custom_divisor = new_serial.custom_divisor;
1137 goto check_and_exit;
1140 if (new_serial.baud_base < 9600)
1141 return -EINVAL;
1143 /*
1144 * OK, past this point, all the error checking has been done.
1145 * At this point, we start making changes.....
1146 */
1148 state->baud_base = new_serial.baud_base;
1149 state->flags = ((state->flags & ~ASYNC_FLAGS) |
1150 (new_serial.flags & ASYNC_FLAGS));
1151 info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) |
1152 (info->flags & ASYNC_INTERNAL_FLAGS));
1153 state->custom_divisor = new_serial.custom_divisor;
1154 state->close_delay = new_serial.close_delay * HZ/100;
1155 state->closing_wait = new_serial.closing_wait * HZ/100;
1156 info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1158 check_and_exit:
1159 if (info->flags & ASYNC_INITIALIZED) {
1160 if (((old_state.flags & ASYNC_SPD_MASK) !=
1161 (state->flags & ASYNC_SPD_MASK)) ||
1162 (old_state.custom_divisor != state->custom_divisor)) {
1163 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1164 info->tty->alt_speed = 57600;
1165 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1166 info->tty->alt_speed = 115200;
1167 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1168 info->tty->alt_speed = 230400;
1169 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1170 info->tty->alt_speed = 460800;
1171 change_speed(info, NULL);
1173 } else
1174 retval = startup(info);
1175 return retval;
1179 /*
1180 * get_lsr_info - get line status register info
1182 * Purpose: Let user call ioctl() to get info when the UART physically
1183 * is emptied. On bus types like RS485, the transmitter must
1184 * release the bus after transmitting. This must be done when
1185 * the transmit shift register is empty, not be done when the
1186 * transmit holding register is empty. This functionality
1187 * allows an RS485 driver to be written in user space.
1188 */
1189 static int get_lsr_info(struct async_struct * info, unsigned int __user *value)
1191 unsigned char status;
1192 unsigned int result;
1193 unsigned long flags;
1195 local_irq_save(flags);
1196 status = custom.serdatr;
1197 mb();
1198 local_irq_restore(flags);
1199 result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
1200 if (copy_to_user(value, &result, sizeof(int)))
1201 return -EFAULT;
1202 return 0;
1206 static int rs_tiocmget(struct tty_struct *tty, struct file *file)
1208 struct async_struct * info = (struct async_struct *)tty->driver_data;
1209 unsigned char control, status;
1210 unsigned long flags;
1212 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1213 return -ENODEV;
1214 if (tty->flags & (1 << TTY_IO_ERROR))
1215 return -EIO;
1217 control = info->MCR;
1218 local_irq_save(flags);
1219 status = ciab.pra;
1220 local_irq_restore(flags);
1221 return ((control & SER_RTS) ? TIOCM_RTS : 0)
1222 | ((control & SER_DTR) ? TIOCM_DTR : 0)
1223 | (!(status & SER_DCD) ? TIOCM_CAR : 0)
1224 | (!(status & SER_DSR) ? TIOCM_DSR : 0)
1225 | (!(status & SER_CTS) ? TIOCM_CTS : 0);
1228 static int rs_tiocmset(struct tty_struct *tty, struct file *file,
1229 unsigned int set, unsigned int clear)
1231 struct async_struct * info = (struct async_struct *)tty->driver_data;
1232 unsigned long flags;
1234 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1235 return -ENODEV;
1236 if (tty->flags & (1 << TTY_IO_ERROR))
1237 return -EIO;
1239 local_irq_save(flags);
1240 if (set & TIOCM_RTS)
1241 info->MCR |= SER_RTS;
1242 if (set & TIOCM_DTR)
1243 info->MCR |= SER_DTR;
1244 if (clear & TIOCM_RTS)
1245 info->MCR &= ~SER_RTS;
1246 if (clear & TIOCM_DTR)
1247 info->MCR &= ~SER_DTR;
1248 rtsdtr_ctrl(info->MCR);
1249 local_irq_restore(flags);
1250 return 0;
1253 /*
1254 * rs_break() --- routine which turns the break handling on or off
1255 */
1256 static void rs_break(struct tty_struct *tty, int break_state)
1258 struct async_struct * info = (struct async_struct *)tty->driver_data;
1259 unsigned long flags;
1261 if (serial_paranoia_check(info, tty->name, "rs_break"))
1262 return;
1264 local_irq_save(flags);
1265 if (break_state == -1)
1266 custom.adkcon = AC_SETCLR | AC_UARTBRK;
1267 else
1268 custom.adkcon = AC_UARTBRK;
1269 mb();
1270 local_irq_restore(flags);
1274 static int rs_ioctl(struct tty_struct *tty, struct file * file,
1275 unsigned int cmd, unsigned long arg)
1277 struct async_struct * info = (struct async_struct *)tty->driver_data;
1278 struct async_icount cprev, cnow; /* kernel counter temps */
1279 struct serial_icounter_struct icount;
1280 void __user *argp = (void __user *)arg;
1281 unsigned long flags;
1283 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1284 return -ENODEV;
1286 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1287 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
1288 (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1289 if (tty->flags & (1 << TTY_IO_ERROR))
1290 return -EIO;
1293 switch (cmd) {
1294 case TIOCGSERIAL:
1295 return get_serial_info(info, argp);
1296 case TIOCSSERIAL:
1297 return set_serial_info(info, argp);
1298 case TIOCSERCONFIG:
1299 return 0;
1301 case TIOCSERGETLSR: /* Get line status register */
1302 return get_lsr_info(info, argp);
1304 case TIOCSERGSTRUCT:
1305 if (copy_to_user(argp,
1306 info, sizeof(struct async_struct)))
1307 return -EFAULT;
1308 return 0;
1310 /*
1311 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1312 * - mask passed in arg for lines of interest
1313 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1314 * Caller should use TIOCGICOUNT to see which one it was
1315 */
1316 case TIOCMIWAIT:
1317 local_irq_save(flags);
1318 /* note the counters on entry */
1319 cprev = info->state->icount;
1320 local_irq_restore(flags);
1321 while (1) {
1322 interruptible_sleep_on(&info->delta_msr_wait);
1323 /* see if a signal did it */
1324 if (signal_pending(current))
1325 return -ERESTARTSYS;
1326 local_irq_save(flags);
1327 cnow = info->state->icount; /* atomic copy */
1328 local_irq_restore(flags);
1329 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
1330 cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1331 return -EIO; /* no change => error */
1332 if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1333 ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1334 ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
1335 ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1336 return 0;
1338 cprev = cnow;
1340 /* NOTREACHED */
1342 /*
1343 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1344 * Return: write counters to the user passed counter struct
1345 * NB: both 1->0 and 0->1 transitions are counted except for
1346 * RI where only 0->1 is counted.
1347 */
1348 case TIOCGICOUNT:
1349 local_irq_save(flags);
1350 cnow = info->state->icount;
1351 local_irq_restore(flags);
1352 icount.cts = cnow.cts;
1353 icount.dsr = cnow.dsr;
1354 icount.rng = cnow.rng;
1355 icount.dcd = cnow.dcd;
1356 icount.rx = cnow.rx;
1357 icount.tx = cnow.tx;
1358 icount.frame = cnow.frame;
1359 icount.overrun = cnow.overrun;
1360 icount.parity = cnow.parity;
1361 icount.brk = cnow.brk;
1362 icount.buf_overrun = cnow.buf_overrun;
1364 if (copy_to_user(argp, &icount, sizeof(icount)))
1365 return -EFAULT;
1366 return 0;
1367 case TIOCSERGWILD:
1368 case TIOCSERSWILD:
1369 /* "setserial -W" is called in Debian boot */
1370 printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
1371 return 0;
1373 default:
1374 return -ENOIOCTLCMD;
1376 return 0;
1379 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
1381 struct async_struct *info = (struct async_struct *)tty->driver_data;
1382 unsigned long flags;
1383 unsigned int cflag = tty->termios->c_cflag;
1385 if ( (cflag == old_termios->c_cflag)
1386 && ( RELEVANT_IFLAG(tty->termios->c_iflag)
1387 == RELEVANT_IFLAG(old_termios->c_iflag)))
1388 return;
1390 change_speed(info, old_termios);
1392 /* Handle transition to B0 status */
1393 if ((old_termios->c_cflag & CBAUD) &&
1394 !(cflag & CBAUD)) {
1395 info->MCR &= ~(SER_DTR|SER_RTS);
1396 local_irq_save(flags);
1397 rtsdtr_ctrl(info->MCR);
1398 local_irq_restore(flags);
1401 /* Handle transition away from B0 status */
1402 if (!(old_termios->c_cflag & CBAUD) &&
1403 (cflag & CBAUD)) {
1404 info->MCR |= SER_DTR;
1405 if (!(tty->termios->c_cflag & CRTSCTS) ||
1406 !test_bit(TTY_THROTTLED, &tty->flags)) {
1407 info->MCR |= SER_RTS;
1409 local_irq_save(flags);
1410 rtsdtr_ctrl(info->MCR);
1411 local_irq_restore(flags);
1414 /* Handle turning off CRTSCTS */
1415 if ((old_termios->c_cflag & CRTSCTS) &&
1416 !(tty->termios->c_cflag & CRTSCTS)) {
1417 tty->hw_stopped = 0;
1418 rs_start(tty);
1421 #if 0
1422 /*
1423 * No need to wake up processes in open wait, since they
1424 * sample the CLOCAL flag once, and don't recheck it.
1425 * XXX It's not clear whether the current behavior is correct
1426 * or not. Hence, this may change.....
1427 */
1428 if (!(old_termios->c_cflag & CLOCAL) &&
1429 (tty->termios->c_cflag & CLOCAL))
1430 wake_up_interruptible(&info->open_wait);
1431 #endif
1434 /*
1435 * ------------------------------------------------------------
1436 * rs_close()
1438 * This routine is called when the serial port gets closed. First, we
1439 * wait for the last remaining data to be sent. Then, we unlink its
1440 * async structure from the interrupt chain if necessary, and we free
1441 * that IRQ if nothing is left in the chain.
1442 * ------------------------------------------------------------
1443 */
1444 static void rs_close(struct tty_struct *tty, struct file * filp)
1446 struct async_struct * info = (struct async_struct *)tty->driver_data;
1447 struct serial_state *state;
1448 unsigned long flags;
1450 if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1451 return;
1453 state = info->state;
1455 local_irq_save(flags);
1457 if (tty_hung_up_p(filp)) {
1458 DBG_CNT("before DEC-hung");
1459 local_irq_restore(flags);
1460 return;
1463 #ifdef SERIAL_DEBUG_OPEN
1464 printk("rs_close ttys%d, count = %d\n", info->line, state->count);
1465 #endif
1466 if ((tty->count == 1) && (state->count != 1)) {
1467 /*
1468 * Uh, oh. tty->count is 1, which means that the tty
1469 * structure will be freed. state->count should always
1470 * be one in these conditions. If it's greater than
1471 * one, we've got real problems, since it means the
1472 * serial port won't be shutdown.
1473 */
1474 printk("rs_close: bad serial port count; tty->count is 1, "
1475 "state->count is %d\n", state->count);
1476 state->count = 1;
1478 if (--state->count < 0) {
1479 printk("rs_close: bad serial port count for ttys%d: %d\n",
1480 info->line, state->count);
1481 state->count = 0;
1483 if (state->count) {
1484 DBG_CNT("before DEC-2");
1485 local_irq_restore(flags);
1486 return;
1488 info->flags |= ASYNC_CLOSING;
1489 /*
1490 * Now we wait for the transmit buffer to clear; and we notify
1491 * the line discipline to only process XON/XOFF characters.
1492 */
1493 tty->closing = 1;
1494 if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1495 tty_wait_until_sent(tty, info->closing_wait);
1496 /*
1497 * At this point we stop accepting input. To do this, we
1498 * disable the receive line status interrupts, and tell the
1499 * interrupt driver to stop checking the data ready bit in the
1500 * line status register.
1501 */
1502 info->read_status_mask &= ~UART_LSR_DR;
1503 if (info->flags & ASYNC_INITIALIZED) {
1504 /* disable receive interrupts */
1505 custom.intena = IF_RBF;
1506 mb();
1507 /* clear any pending receive interrupt */
1508 custom.intreq = IF_RBF;
1509 mb();
1511 /*
1512 * Before we drop DTR, make sure the UART transmitter
1513 * has completely drained; this is especially
1514 * important if there is a transmit FIFO!
1515 */
1516 rs_wait_until_sent(tty, info->timeout);
1518 shutdown(info);
1519 if (tty->driver->flush_buffer)
1520 tty->driver->flush_buffer(tty);
1522 tty_ldisc_flush(tty);
1523 tty->closing = 0;
1524 info->event = 0;
1525 info->tty = NULL;
1526 if (info->blocked_open) {
1527 if (info->close_delay) {
1528 msleep_interruptible(jiffies_to_msecs(info->close_delay));
1530 wake_up_interruptible(&info->open_wait);
1532 info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
1533 wake_up_interruptible(&info->close_wait);
1534 local_irq_restore(flags);
1537 /*
1538 * rs_wait_until_sent() --- wait until the transmitter is empty
1539 */
1540 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1542 struct async_struct * info = (struct async_struct *)tty->driver_data;
1543 unsigned long orig_jiffies, char_time;
1544 int lsr;
1546 if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
1547 return;
1549 if (info->xmit_fifo_size == 0)
1550 return; /* Just in case.... */
1552 orig_jiffies = jiffies;
1553 /*
1554 * Set the check interval to be 1/5 of the estimated time to
1555 * send a single character, and make it at least 1. The check
1556 * interval should also be less than the timeout.
1558 * Note: we have to use pretty tight timings here to satisfy
1559 * the NIST-PCTS.
1560 */
1561 char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1562 char_time = char_time / 5;
1563 if (char_time == 0)
1564 char_time = 1;
1565 if (timeout)
1566 char_time = min_t(unsigned long, char_time, timeout);
1567 /*
1568 * If the transmitter hasn't cleared in twice the approximate
1569 * amount of time to send the entire FIFO, it probably won't
1570 * ever clear. This assumes the UART isn't doing flow
1571 * control, which is currently the case. Hence, if it ever
1572 * takes longer than info->timeout, this is probably due to a
1573 * UART bug of some kind. So, we clamp the timeout parameter at
1574 * 2*info->timeout.
1575 */
1576 if (!timeout || timeout > 2*info->timeout)
1577 timeout = 2*info->timeout;
1578 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1579 printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
1580 printk("jiff=%lu...", jiffies);
1581 #endif
1582 while(!((lsr = custom.serdatr) & SDR_TSRE)) {
1583 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1584 printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
1585 #endif
1586 msleep_interruptible(jiffies_to_msecs(char_time));
1587 if (signal_pending(current))
1588 break;
1589 if (timeout && time_after(jiffies, orig_jiffies + timeout))
1590 break;
1592 current->state = TASK_RUNNING;
1593 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1594 printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1595 #endif
1598 /*
1599 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1600 */
1601 static void rs_hangup(struct tty_struct *tty)
1603 struct async_struct * info = (struct async_struct *)tty->driver_data;
1604 struct serial_state *state = info->state;
1606 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1607 return;
1609 state = info->state;
1611 rs_flush_buffer(tty);
1612 shutdown(info);
1613 info->event = 0;
1614 state->count = 0;
1615 info->flags &= ~ASYNC_NORMAL_ACTIVE;
1616 info->tty = NULL;
1617 wake_up_interruptible(&info->open_wait);
1620 /*
1621 * ------------------------------------------------------------
1622 * rs_open() and friends
1623 * ------------------------------------------------------------
1624 */
1625 static int block_til_ready(struct tty_struct *tty, struct file * filp,
1626 struct async_struct *info)
1628 #ifdef DECLARE_WAITQUEUE
1629 DECLARE_WAITQUEUE(wait, current);
1630 #else
1631 struct wait_queue wait = { current, NULL };
1632 #endif
1633 struct serial_state *state = info->state;
1634 int retval;
1635 int do_clocal = 0, extra_count = 0;
1636 unsigned long flags;
1638 /*
1639 * If the device is in the middle of being closed, then block
1640 * until it's done, and then try again.
1641 */
1642 if (tty_hung_up_p(filp) ||
1643 (info->flags & ASYNC_CLOSING)) {
1644 if (info->flags & ASYNC_CLOSING)
1645 interruptible_sleep_on(&info->close_wait);
1646 #ifdef SERIAL_DO_RESTART
1647 return ((info->flags & ASYNC_HUP_NOTIFY) ?
1648 -EAGAIN : -ERESTARTSYS);
1649 #else
1650 return -EAGAIN;
1651 #endif
1654 /*
1655 * If non-blocking mode is set, or the port is not enabled,
1656 * then make the check up front and then exit.
1657 */
1658 if ((filp->f_flags & O_NONBLOCK) ||
1659 (tty->flags & (1 << TTY_IO_ERROR))) {
1660 info->flags |= ASYNC_NORMAL_ACTIVE;
1661 return 0;
1664 if (tty->termios->c_cflag & CLOCAL)
1665 do_clocal = 1;
1667 /*
1668 * Block waiting for the carrier detect and the line to become
1669 * free (i.e., not in use by the callout). While we are in
1670 * this loop, state->count is dropped by one, so that
1671 * rs_close() knows when to free things. We restore it upon
1672 * exit, either normal or abnormal.
1673 */
1674 retval = 0;
1675 add_wait_queue(&info->open_wait, &wait);
1676 #ifdef SERIAL_DEBUG_OPEN
1677 printk("block_til_ready before block: ttys%d, count = %d\n",
1678 state->line, state->count);
1679 #endif
1680 local_irq_save(flags);
1681 if (!tty_hung_up_p(filp)) {
1682 extra_count = 1;
1683 state->count--;
1685 local_irq_restore(flags);
1686 info->blocked_open++;
1687 while (1) {
1688 local_irq_save(flags);
1689 if (tty->termios->c_cflag & CBAUD)
1690 rtsdtr_ctrl(SER_DTR|SER_RTS);
1691 local_irq_restore(flags);
1692 set_current_state(TASK_INTERRUPTIBLE);
1693 if (tty_hung_up_p(filp) ||
1694 !(info->flags & ASYNC_INITIALIZED)) {
1695 #ifdef SERIAL_DO_RESTART
1696 if (info->flags & ASYNC_HUP_NOTIFY)
1697 retval = -EAGAIN;
1698 else
1699 retval = -ERESTARTSYS;
1700 #else
1701 retval = -EAGAIN;
1702 #endif
1703 break;
1705 if (!(info->flags & ASYNC_CLOSING) &&
1706 (do_clocal || (!(ciab.pra & SER_DCD)) ))
1707 break;
1708 if (signal_pending(current)) {
1709 retval = -ERESTARTSYS;
1710 break;
1712 #ifdef SERIAL_DEBUG_OPEN
1713 printk("block_til_ready blocking: ttys%d, count = %d\n",
1714 info->line, state->count);
1715 #endif
1716 schedule();
1718 current->state = TASK_RUNNING;
1719 remove_wait_queue(&info->open_wait, &wait);
1720 if (extra_count)
1721 state->count++;
1722 info->blocked_open--;
1723 #ifdef SERIAL_DEBUG_OPEN
1724 printk("block_til_ready after blocking: ttys%d, count = %d\n",
1725 info->line, state->count);
1726 #endif
1727 if (retval)
1728 return retval;
1729 info->flags |= ASYNC_NORMAL_ACTIVE;
1730 return 0;
1733 static int get_async_struct(int line, struct async_struct **ret_info)
1735 struct async_struct *info;
1736 struct serial_state *sstate;
1738 sstate = rs_table + line;
1739 sstate->count++;
1740 if (sstate->info) {
1741 *ret_info = sstate->info;
1742 return 0;
1744 info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
1745 if (!info) {
1746 sstate->count--;
1747 return -ENOMEM;
1749 memset(info, 0, sizeof(struct async_struct));
1750 #ifdef DECLARE_WAITQUEUE
1751 init_waitqueue_head(&info->open_wait);
1752 init_waitqueue_head(&info->close_wait);
1753 init_waitqueue_head(&info->delta_msr_wait);
1754 #endif
1755 info->magic = SERIAL_MAGIC;
1756 info->port = sstate->port;
1757 info->flags = sstate->flags;
1758 info->xmit_fifo_size = sstate->xmit_fifo_size;
1759 info->line = line;
1760 tasklet_init(&info->tlet, do_softint, (unsigned long)info);
1761 info->state = sstate;
1762 if (sstate->info) {
1763 kfree(info);
1764 *ret_info = sstate->info;
1765 return 0;
1767 *ret_info = sstate->info = info;
1768 return 0;
1771 /*
1772 * This routine is called whenever a serial port is opened. It
1773 * enables interrupts for a serial port, linking in its async structure into
1774 * the IRQ chain. It also performs the serial-specific
1775 * initialization for the tty structure.
1776 */
1777 static int rs_open(struct tty_struct *tty, struct file * filp)
1779 struct async_struct *info;
1780 int retval, line;
1781 unsigned long page;
1783 line = tty->index;
1784 if ((line < 0) || (line >= NR_PORTS)) {
1785 return -ENODEV;
1787 retval = get_async_struct(line, &info);
1788 if (retval) {
1789 return retval;
1791 tty->driver_data = info;
1792 info->tty = tty;
1793 if (serial_paranoia_check(info, tty->name, "rs_open"))
1794 return -ENODEV;
1796 #ifdef SERIAL_DEBUG_OPEN
1797 printk("rs_open %s, count = %d\n", tty->name, info->state->count);
1798 #endif
1799 info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1801 if (!tmp_buf) {
1802 page = get_zeroed_page(GFP_KERNEL);
1803 if (!page) {
1804 return -ENOMEM;
1806 if (tmp_buf)
1807 free_page(page);
1808 else
1809 tmp_buf = (unsigned char *) page;
1812 /*
1813 * If the port is the middle of closing, bail out now
1814 */
1815 if (tty_hung_up_p(filp) ||
1816 (info->flags & ASYNC_CLOSING)) {
1817 if (info->flags & ASYNC_CLOSING)
1818 interruptible_sleep_on(&info->close_wait);
1819 #ifdef SERIAL_DO_RESTART
1820 return ((info->flags & ASYNC_HUP_NOTIFY) ?
1821 -EAGAIN : -ERESTARTSYS);
1822 #else
1823 return -EAGAIN;
1824 #endif
1827 /*
1828 * Start up serial port
1829 */
1830 retval = startup(info);
1831 if (retval) {
1832 return retval;
1835 retval = block_til_ready(tty, filp, info);
1836 if (retval) {
1837 #ifdef SERIAL_DEBUG_OPEN
1838 printk("rs_open returning after block_til_ready with %d\n",
1839 retval);
1840 #endif
1841 return retval;
1844 #ifdef SERIAL_DEBUG_OPEN
1845 printk("rs_open %s successful...", tty->name);
1846 #endif
1847 return 0;
1850 /*
1851 * /proc fs routines....
1852 */
1854 static inline int line_info(char *buf, struct serial_state *state)
1856 struct async_struct *info = state->info, scr_info;
1857 char stat_buf[30], control, status;
1858 int ret;
1859 unsigned long flags;
1861 ret = sprintf(buf, "%d: uart:amiga_builtin",state->line);
1863 /*
1864 * Figure out the current RS-232 lines
1865 */
1866 if (!info) {
1867 info = &scr_info; /* This is just for serial_{in,out} */
1869 info->magic = SERIAL_MAGIC;
1870 info->flags = state->flags;
1871 info->quot = 0;
1872 info->tty = NULL;
1874 local_irq_save(flags);
1875 status = ciab.pra;
1876 control = info ? info->MCR : status;
1877 local_irq_restore(flags);
1879 stat_buf[0] = 0;
1880 stat_buf[1] = 0;
1881 if(!(control & SER_RTS))
1882 strcat(stat_buf, "|RTS");
1883 if(!(status & SER_CTS))
1884 strcat(stat_buf, "|CTS");
1885 if(!(control & SER_DTR))
1886 strcat(stat_buf, "|DTR");
1887 if(!(status & SER_DSR))
1888 strcat(stat_buf, "|DSR");
1889 if(!(status & SER_DCD))
1890 strcat(stat_buf, "|CD");
1892 if (info->quot) {
1893 ret += sprintf(buf+ret, " baud:%d",
1894 state->baud_base / info->quot);
1897 ret += sprintf(buf+ret, " tx:%d rx:%d",
1898 state->icount.tx, state->icount.rx);
1900 if (state->icount.frame)
1901 ret += sprintf(buf+ret, " fe:%d", state->icount.frame);
1903 if (state->icount.parity)
1904 ret += sprintf(buf+ret, " pe:%d", state->icount.parity);
1906 if (state->icount.brk)
1907 ret += sprintf(buf+ret, " brk:%d", state->icount.brk);
1909 if (state->icount.overrun)
1910 ret += sprintf(buf+ret, " oe:%d", state->icount.overrun);
1912 /*
1913 * Last thing is the RS-232 status lines
1914 */
1915 ret += sprintf(buf+ret, " %s\n", stat_buf+1);
1916 return ret;
1919 static int rs_read_proc(char *page, char **start, off_t off, int count,
1920 int *eof, void *data)
1922 int len = 0, l;
1923 off_t begin = 0;
1925 len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
1926 l = line_info(page + len, &rs_table[0]);
1927 len += l;
1928 if (len+begin > off+count)
1929 goto done;
1930 if (len+begin < off) {
1931 begin += len;
1932 len = 0;
1934 *eof = 1;
1935 done:
1936 if (off >= len+begin)
1937 return 0;
1938 *start = page + (off-begin);
1939 return ((count < begin+len-off) ? count : begin+len-off);
1942 /*
1943 * ---------------------------------------------------------------------
1944 * rs_init() and friends
1946 * rs_init() is called at boot-time to initialize the serial driver.
1947 * ---------------------------------------------------------------------
1948 */
1950 /*
1951 * This routine prints out the appropriate serial driver version
1952 * number, and identifies which options were configured into this
1953 * driver.
1954 */
1955 static void show_serial_version(void)
1957 printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
1961 static struct tty_operations serial_ops = {
1962 .open = rs_open,
1963 .close = rs_close,
1964 .write = rs_write,
1965 .put_char = rs_put_char,
1966 .flush_chars = rs_flush_chars,
1967 .write_room = rs_write_room,
1968 .chars_in_buffer = rs_chars_in_buffer,
1969 .flush_buffer = rs_flush_buffer,
1970 .ioctl = rs_ioctl,
1971 .throttle = rs_throttle,
1972 .unthrottle = rs_unthrottle,
1973 .set_termios = rs_set_termios,
1974 .stop = rs_stop,
1975 .start = rs_start,
1976 .hangup = rs_hangup,
1977 .break_ctl = rs_break,
1978 .send_xchar = rs_send_xchar,
1979 .wait_until_sent = rs_wait_until_sent,
1980 .read_proc = rs_read_proc,
1981 .tiocmget = rs_tiocmget,
1982 .tiocmset = rs_tiocmset,
1983 };
1985 /*
1986 * The serial driver boot-time initialization code!
1987 */
1988 static int __init rs_init(void)
1990 unsigned long flags;
1991 struct serial_state * state;
1993 if (!MACH_IS_AMIGA || !AMIGAHW_PRESENT(AMI_SERIAL))
1994 return -ENODEV;
1996 serial_driver = alloc_tty_driver(1);
1997 if (!serial_driver)
1998 return -ENOMEM;
2000 /*
2001 * We request SERDAT and SERPER only, because the serial registers are
2002 * too spreaded over the custom register space
2003 */
2004 if (!request_mem_region(CUSTOM_PHYSADDR+0x30, 4, "amiserial [Paula]"))
2005 return -EBUSY;
2007 IRQ_ports = NULL;
2009 show_serial_version();
2011 /* Initialize the tty_driver structure */
2013 serial_driver->owner = THIS_MODULE;
2014 serial_driver->driver_name = "amiserial";
2015 serial_driver->name = "ttyS";
2016 serial_driver->major = TTY_MAJOR;
2017 serial_driver->minor_start = 64;
2018 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
2019 serial_driver->subtype = SERIAL_TYPE_NORMAL;
2020 serial_driver->init_termios = tty_std_termios;
2021 serial_driver->init_termios.c_cflag =
2022 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
2023 serial_driver->flags = TTY_DRIVER_REAL_RAW;
2024 tty_set_operations(serial_driver, &serial_ops);
2026 if (tty_register_driver(serial_driver))
2027 panic("Couldn't register serial driver\n");
2029 state = rs_table;
2030 state->magic = SSTATE_MAGIC;
2031 state->port = (int)&custom.serdatr; /* Just to give it a value */
2032 state->line = 0;
2033 state->custom_divisor = 0;
2034 state->close_delay = 5*HZ/10;
2035 state->closing_wait = 30*HZ;
2036 state->icount.cts = state->icount.dsr =
2037 state->icount.rng = state->icount.dcd = 0;
2038 state->icount.rx = state->icount.tx = 0;
2039 state->icount.frame = state->icount.parity = 0;
2040 state->icount.overrun = state->icount.brk = 0;
2042 printk(KERN_INFO "ttyS%d is the amiga builtin serial port\n",
2043 state->line);
2045 /* Hardware set up */
2047 state->baud_base = amiga_colorclock;
2048 state->xmit_fifo_size = 1;
2050 local_irq_save(flags);
2052 /* set ISRs, and then disable the rx interrupts */
2053 request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
2054 request_irq(IRQ_AMIGA_RBF, ser_rx_int, IRQF_DISABLED, "serial RX", state);
2056 /* turn off Rx and Tx interrupts */
2057 custom.intena = IF_RBF | IF_TBE;
2058 mb();
2060 /* clear any pending interrupt */
2061 custom.intreq = IF_RBF | IF_TBE;
2062 mb();
2064 local_irq_restore(flags);
2066 /*
2067 * set the appropriate directions for the modem control flags,
2068 * and clear RTS and DTR
2069 */
2070 ciab.ddra |= (SER_DTR | SER_RTS); /* outputs */
2071 ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR); /* inputs */
2073 return 0;
2076 static __exit void rs_exit(void)
2078 int error;
2079 struct async_struct *info = rs_table[0].info;
2081 /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
2082 tasklet_kill(&info->tlet);
2083 if ((error = tty_unregister_driver(serial_driver)))
2084 printk("SERIAL: failed to unregister serial driver (%d)\n",
2085 error);
2086 put_tty_driver(serial_driver);
2088 if (info) {
2089 rs_table[0].info = NULL;
2090 kfree(info);
2093 if (tmp_buf) {
2094 free_page((unsigned long) tmp_buf);
2095 tmp_buf = NULL;
2098 release_mem_region(CUSTOM_PHYSADDR+0x30, 4);
2101 module_init(rs_init)
2102 module_exit(rs_exit)
2105 /*
2106 * ------------------------------------------------------------
2107 * Serial console driver
2108 * ------------------------------------------------------------
2109 */
2110 #ifdef CONFIG_SERIAL_CONSOLE
2112 static void amiga_serial_putc(char c)
2114 custom.serdat = (unsigned char)c | 0x100;
2115 while (!(custom.serdatr & 0x2000))
2116 barrier();
2119 /*
2120 * Print a string to the serial port trying not to disturb
2121 * any possible real use of the port...
2123 * The console must be locked when we get here.
2124 */
2125 static void serial_console_write(struct console *co, const char *s,
2126 unsigned count)
2128 unsigned short intena = custom.intenar;
2130 custom.intena = IF_TBE;
2132 while (count--) {
2133 if (*s == '\n')
2134 amiga_serial_putc('\r');
2135 amiga_serial_putc(*s++);
2138 custom.intena = IF_SETCLR | (intena & IF_TBE);
2141 static struct tty_driver *serial_console_device(struct console *c, int *index)
2143 *index = 0;
2144 return serial_driver;
2147 static struct console sercons = {
2148 .name = "ttyS",
2149 .write = serial_console_write,
2150 .device = serial_console_device,
2151 .flags = CON_PRINTBUFFER,
2152 .index = -1,
2153 };
2155 /*
2156 * Register console.
2157 */
2158 static int __init amiserial_console_init(void)
2160 register_console(&sercons);
2161 return 0;
2163 console_initcall(amiserial_console_init);
2164 #endif
2166 MODULE_LICENSE("GPL");