Add linux-next specific files for 20110831
[linux-2.6/next.git] / drivers / tty / amiserial.c
blob6d43f550b5498d3a04272ee980f07ad7c2dfc4b1
1 /*
2 * Serial driver for the amiga builtin port.
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.
13 * The port is registered with the tty driver as minor device 64, and
14 * therefore other ports should should only use 65 upwards.
16 * Richard Lucock 28/12/99
18 * Copyright (C) 1991, 1992 Linus Torvalds
19 * Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997,
20 * 1998, 1999 Theodore Ts'o
25 * Serial driver configuration section. Here are the various options:
27 * SERIAL_PARANOIA_CHECK
28 * Check the magic number for the async_structure where
29 * ever possible.
32 #include <linux/delay.h>
34 #undef SERIAL_PARANOIA_CHECK
35 #define SERIAL_DO_RESTART
37 /* Set of debugging defines */
39 #undef SERIAL_DEBUG_INTR
40 #undef SERIAL_DEBUG_OPEN
41 #undef SERIAL_DEBUG_FLOW
42 #undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
44 /* Sanity checks */
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->flags), serial_driver->refcount,info->count,tty->count,s)
49 #else
50 #define DBG_CNT(s)
51 #endif
54 * End of serial driver configuration section.
57 #include <linux/module.h>
59 #include <linux/types.h>
60 #include <linux/serial.h>
61 #include <linux/serialP.h>
62 #include <linux/serial_reg.h>
63 static char *serial_version = "4.30";
65 #include <linux/errno.h>
66 #include <linux/signal.h>
67 #include <linux/sched.h>
68 #include <linux/kernel.h>
69 #include <linux/timer.h>
70 #include <linux/interrupt.h>
71 #include <linux/tty.h>
72 #include <linux/tty_flip.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>
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 ktermios *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 #include <asm/uaccess.h>
117 #define serial_isroot() (capable(CAP_SYS_ADMIN))
120 static inline int serial_paranoia_check(struct async_struct *info,
121 char *name, const char *routine)
123 #ifdef SERIAL_PARANOIA_CHECK
124 static const char *badmagic =
125 "Warning: bad magic number for serial struct (%s) in %s\n";
126 static const char *badinfo =
127 "Warning: null async_struct for (%s) in %s\n";
129 if (!info) {
130 printk(badinfo, name, routine);
131 return 1;
133 if (info->magic != SERIAL_MAGIC) {
134 printk(badmagic, name, routine);
135 return 1;
137 #endif
138 return 0;
141 /* some serial hardware definitions */
142 #define SDR_OVRUN (1<<15)
143 #define SDR_RBF (1<<14)
144 #define SDR_TBE (1<<13)
145 #define SDR_TSRE (1<<12)
147 #define SERPER_PARENB (1<<15)
149 #define AC_SETCLR (1<<15)
150 #define AC_UARTBRK (1<<11)
152 #define SER_DTR (1<<7)
153 #define SER_RTS (1<<6)
154 #define SER_DCD (1<<5)
155 #define SER_CTS (1<<4)
156 #define SER_DSR (1<<3)
158 static __inline__ void rtsdtr_ctrl(int bits)
160 ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
164 * ------------------------------------------------------------
165 * rs_stop() and rs_start()
167 * This routines are called before setting or resetting tty->stopped.
168 * They enable or disable transmitter interrupts, as necessary.
169 * ------------------------------------------------------------
171 static void rs_stop(struct tty_struct *tty)
173 struct async_struct *info = tty->driver_data;
174 unsigned long flags;
176 if (serial_paranoia_check(info, tty->name, "rs_stop"))
177 return;
179 local_irq_save(flags);
180 if (info->IER & UART_IER_THRI) {
181 info->IER &= ~UART_IER_THRI;
182 /* disable Tx interrupt and remove any pending interrupts */
183 custom.intena = IF_TBE;
184 mb();
185 custom.intreq = IF_TBE;
186 mb();
188 local_irq_restore(flags);
191 static void rs_start(struct tty_struct *tty)
193 struct async_struct *info = tty->driver_data;
194 unsigned long flags;
196 if (serial_paranoia_check(info, tty->name, "rs_start"))
197 return;
199 local_irq_save(flags);
200 if (info->xmit.head != info->xmit.tail
201 && info->xmit.buf
202 && !(info->IER & UART_IER_THRI)) {
203 info->IER |= UART_IER_THRI;
204 custom.intena = IF_SETCLR | IF_TBE;
205 mb();
206 /* set a pending Tx Interrupt, transmitter should restart now */
207 custom.intreq = IF_SETCLR | IF_TBE;
208 mb();
210 local_irq_restore(flags);
214 * ----------------------------------------------------------------------
216 * Here starts the interrupt handling routines. All of the following
217 * subroutines are declared as inline and are folded into
218 * rs_interrupt(). They were separated out for readability's sake.
220 * Note: rs_interrupt() is a "fast" interrupt, which means that it
221 * runs with interrupts turned off. People who may want to modify
222 * rs_interrupt() should try to keep the interrupt handler as fast as
223 * possible. After you are done making modifications, it is not a bad
224 * idea to do:
226 * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
228 * and look at the resulting assemble code in serial.s.
230 * - Ted Ts'o (tytso@mit.edu), 7-Mar-93
231 * -----------------------------------------------------------------------
235 * This routine is used by the interrupt handler to schedule
236 * processing in the software interrupt portion of the driver.
238 static void rs_sched_event(struct async_struct *info,
239 int event)
241 info->event |= 1 << event;
242 tasklet_schedule(&info->tlet);
245 static void receive_chars(struct async_struct *info)
247 int status;
248 int serdatr;
249 struct tty_struct *tty = info->tty;
250 unsigned char ch, flag;
251 struct async_icount *icount;
252 int oe = 0;
254 icount = &info->state->icount;
256 status = UART_LSR_DR; /* We obviously have a character! */
257 serdatr = custom.serdatr;
258 mb();
259 custom.intreq = IF_RBF;
260 mb();
262 if((serdatr & 0x1ff) == 0)
263 status |= UART_LSR_BI;
264 if(serdatr & SDR_OVRUN)
265 status |= UART_LSR_OE;
267 ch = serdatr & 0xff;
268 icount->rx++;
270 #ifdef SERIAL_DEBUG_INTR
271 printk("DR%02x:%02x...", ch, status);
272 #endif
273 flag = TTY_NORMAL;
276 * We don't handle parity or frame errors - but I have left
277 * the code in, since I'm not sure that the errors can't be
278 * detected.
281 if (status & (UART_LSR_BI | UART_LSR_PE |
282 UART_LSR_FE | UART_LSR_OE)) {
284 * For statistics only
286 if (status & UART_LSR_BI) {
287 status &= ~(UART_LSR_FE | UART_LSR_PE);
288 icount->brk++;
289 } else if (status & UART_LSR_PE)
290 icount->parity++;
291 else if (status & UART_LSR_FE)
292 icount->frame++;
293 if (status & UART_LSR_OE)
294 icount->overrun++;
297 * Now check to see if character should be
298 * ignored, and mask off conditions which
299 * should be ignored.
301 if (status & info->ignore_status_mask)
302 goto out;
304 status &= info->read_status_mask;
306 if (status & (UART_LSR_BI)) {
307 #ifdef SERIAL_DEBUG_INTR
308 printk("handling break....");
309 #endif
310 flag = TTY_BREAK;
311 if (info->flags & ASYNC_SAK)
312 do_SAK(tty);
313 } else if (status & UART_LSR_PE)
314 flag = TTY_PARITY;
315 else if (status & UART_LSR_FE)
316 flag = TTY_FRAME;
317 if (status & UART_LSR_OE) {
319 * Overrun is special, since it's
320 * reported immediately, and doesn't
321 * affect the current character
323 oe = 1;
326 tty_insert_flip_char(tty, ch, flag);
327 if (oe == 1)
328 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
329 tty_flip_buffer_push(tty);
330 out:
331 return;
334 static void transmit_chars(struct async_struct *info)
336 custom.intreq = IF_TBE;
337 mb();
338 if (info->x_char) {
339 custom.serdat = info->x_char | 0x100;
340 mb();
341 info->state->icount.tx++;
342 info->x_char = 0;
343 return;
345 if (info->xmit.head == info->xmit.tail
346 || info->tty->stopped
347 || info->tty->hw_stopped) {
348 info->IER &= ~UART_IER_THRI;
349 custom.intena = IF_TBE;
350 mb();
351 return;
354 custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
355 mb();
356 info->xmit.tail = info->xmit.tail & (SERIAL_XMIT_SIZE-1);
357 info->state->icount.tx++;
359 if (CIRC_CNT(info->xmit.head,
360 info->xmit.tail,
361 SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
362 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
364 #ifdef SERIAL_DEBUG_INTR
365 printk("THRE...");
366 #endif
367 if (info->xmit.head == info->xmit.tail) {
368 custom.intena = IF_TBE;
369 mb();
370 info->IER &= ~UART_IER_THRI;
374 static void check_modem_status(struct async_struct *info)
376 unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
377 unsigned char dstatus;
378 struct async_icount *icount;
380 /* Determine bits that have changed */
381 dstatus = status ^ current_ctl_bits;
382 current_ctl_bits = status;
384 if (dstatus) {
385 icount = &info->state->icount;
386 /* update input line counters */
387 if (dstatus & SER_DSR)
388 icount->dsr++;
389 if (dstatus & SER_DCD) {
390 icount->dcd++;
391 #ifdef CONFIG_HARD_PPS
392 if ((info->flags & ASYNC_HARDPPS_CD) &&
393 !(status & SER_DCD))
394 hardpps();
395 #endif
397 if (dstatus & SER_CTS)
398 icount->cts++;
399 wake_up_interruptible(&info->delta_msr_wait);
402 if ((info->flags & ASYNC_CHECK_CD) && (dstatus & SER_DCD)) {
403 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
404 printk("ttyS%d CD now %s...", info->line,
405 (!(status & SER_DCD)) ? "on" : "off");
406 #endif
407 if (!(status & SER_DCD))
408 wake_up_interruptible(&info->open_wait);
409 else {
410 #ifdef SERIAL_DEBUG_OPEN
411 printk("doing serial hangup...");
412 #endif
413 if (info->tty)
414 tty_hangup(info->tty);
417 if (info->flags & ASYNC_CTS_FLOW) {
418 if (info->tty->hw_stopped) {
419 if (!(status & SER_CTS)) {
420 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
421 printk("CTS tx start...");
422 #endif
423 info->tty->hw_stopped = 0;
424 info->IER |= UART_IER_THRI;
425 custom.intena = IF_SETCLR | IF_TBE;
426 mb();
427 /* set a pending Tx Interrupt, transmitter should restart now */
428 custom.intreq = IF_SETCLR | IF_TBE;
429 mb();
430 rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
431 return;
433 } else {
434 if ((status & SER_CTS)) {
435 #if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
436 printk("CTS tx stop...");
437 #endif
438 info->tty->hw_stopped = 1;
439 info->IER &= ~UART_IER_THRI;
440 /* disable Tx interrupt and remove any pending interrupts */
441 custom.intena = IF_TBE;
442 mb();
443 custom.intreq = IF_TBE;
444 mb();
450 static irqreturn_t ser_vbl_int( int irq, void *data)
452 /* vbl is just a periodic interrupt we tie into to update modem status */
453 struct async_struct * info = IRQ_ports;
455 * TBD - is it better to unregister from this interrupt or to
456 * ignore it if MSI is clear ?
458 if(info->IER & UART_IER_MSI)
459 check_modem_status(info);
460 return IRQ_HANDLED;
463 static irqreturn_t ser_rx_int(int irq, void *dev_id)
465 struct async_struct * info;
467 #ifdef SERIAL_DEBUG_INTR
468 printk("ser_rx_int...");
469 #endif
471 info = IRQ_ports;
472 if (!info || !info->tty)
473 return IRQ_NONE;
475 receive_chars(info);
476 info->last_active = jiffies;
477 #ifdef SERIAL_DEBUG_INTR
478 printk("end.\n");
479 #endif
480 return IRQ_HANDLED;
483 static irqreturn_t ser_tx_int(int irq, void *dev_id)
485 struct async_struct * info;
487 if (custom.serdatr & SDR_TBE) {
488 #ifdef SERIAL_DEBUG_INTR
489 printk("ser_tx_int...");
490 #endif
492 info = IRQ_ports;
493 if (!info || !info->tty)
494 return IRQ_NONE;
496 transmit_chars(info);
497 info->last_active = jiffies;
498 #ifdef SERIAL_DEBUG_INTR
499 printk("end.\n");
500 #endif
502 return IRQ_HANDLED;
506 * -------------------------------------------------------------------
507 * Here ends the serial interrupt routines.
508 * -------------------------------------------------------------------
512 * This routine is used to handle the "bottom half" processing for the
513 * serial driver, known also the "software interrupt" processing.
514 * This processing is done at the kernel interrupt level, after the
515 * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON. This
516 * is where time-consuming activities which can not be done in the
517 * interrupt driver proper are done; the interrupt driver schedules
518 * them using rs_sched_event(), and they get done here.
521 static void do_softint(unsigned long private_)
523 struct async_struct *info = (struct async_struct *) private_;
524 struct tty_struct *tty;
526 tty = info->tty;
527 if (!tty)
528 return;
530 if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event))
531 tty_wakeup(tty);
535 * ---------------------------------------------------------------
536 * Low level utility subroutines for the serial driver: routines to
537 * figure out the appropriate timeout for an interrupt chain, routines
538 * to initialize and startup a serial port, and routines to shutdown a
539 * serial port. Useful stuff like that.
540 * ---------------------------------------------------------------
543 static int startup(struct async_struct * info)
545 unsigned long flags;
546 int retval=0;
547 unsigned long page;
549 page = get_zeroed_page(GFP_KERNEL);
550 if (!page)
551 return -ENOMEM;
553 local_irq_save(flags);
555 if (info->flags & ASYNC_INITIALIZED) {
556 free_page(page);
557 goto errout;
560 if (info->xmit.buf)
561 free_page(page);
562 else
563 info->xmit.buf = (unsigned char *) page;
565 #ifdef SERIAL_DEBUG_OPEN
566 printk("starting up ttys%d ...", info->line);
567 #endif
569 /* Clear anything in the input buffer */
571 custom.intreq = IF_RBF;
572 mb();
574 retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
575 if (retval) {
576 if (serial_isroot()) {
577 if (info->tty)
578 set_bit(TTY_IO_ERROR,
579 &info->tty->flags);
580 retval = 0;
582 goto errout;
585 /* enable both Rx and Tx interrupts */
586 custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
587 mb();
588 info->IER = UART_IER_MSI;
590 /* remember current state of the DCD and CTS bits */
591 current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
593 IRQ_ports = info;
595 info->MCR = 0;
596 if (info->tty->termios->c_cflag & CBAUD)
597 info->MCR = SER_DTR | SER_RTS;
598 rtsdtr_ctrl(info->MCR);
600 if (info->tty)
601 clear_bit(TTY_IO_ERROR, &info->tty->flags);
602 info->xmit.head = info->xmit.tail = 0;
605 * Set up the tty->alt_speed kludge
607 if (info->tty) {
608 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
609 info->tty->alt_speed = 57600;
610 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
611 info->tty->alt_speed = 115200;
612 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
613 info->tty->alt_speed = 230400;
614 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
615 info->tty->alt_speed = 460800;
619 * and set the speed of the serial port
621 change_speed(info, NULL);
623 info->flags |= ASYNC_INITIALIZED;
624 local_irq_restore(flags);
625 return 0;
627 errout:
628 local_irq_restore(flags);
629 return retval;
633 * This routine will shutdown a serial port; interrupts are disabled, and
634 * DTR is dropped if the hangup on close termio flag is on.
636 static void shutdown(struct async_struct * info)
638 unsigned long flags;
639 struct serial_state *state;
641 if (!(info->flags & ASYNC_INITIALIZED))
642 return;
644 state = info->state;
646 #ifdef SERIAL_DEBUG_OPEN
647 printk("Shutting down serial port %d ....\n", info->line);
648 #endif
650 local_irq_save(flags); /* Disable interrupts */
653 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
654 * here so the queue might never be waken up
656 wake_up_interruptible(&info->delta_msr_wait);
658 IRQ_ports = NULL;
661 * Free the IRQ, if necessary
663 free_irq(IRQ_AMIGA_VERTB, info);
665 if (info->xmit.buf) {
666 free_page((unsigned long) info->xmit.buf);
667 info->xmit.buf = NULL;
670 info->IER = 0;
671 custom.intena = IF_RBF | IF_TBE;
672 mb();
674 /* disable break condition */
675 custom.adkcon = AC_UARTBRK;
676 mb();
678 if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
679 info->MCR &= ~(SER_DTR|SER_RTS);
680 rtsdtr_ctrl(info->MCR);
682 if (info->tty)
683 set_bit(TTY_IO_ERROR, &info->tty->flags);
685 info->flags &= ~ASYNC_INITIALIZED;
686 local_irq_restore(flags);
691 * This routine is called to set the UART divisor registers to match
692 * the specified baud rate for a serial port.
694 static void change_speed(struct async_struct *info,
695 struct ktermios *old_termios)
697 int quot = 0, baud_base, baud;
698 unsigned cflag, cval = 0;
699 int bits;
700 unsigned long flags;
702 if (!info->tty || !info->tty->termios)
703 return;
704 cflag = info->tty->termios->c_cflag;
706 /* Byte size is always 8 bits plus parity bit if requested */
708 cval = 3; bits = 10;
709 if (cflag & CSTOPB) {
710 cval |= 0x04;
711 bits++;
713 if (cflag & PARENB) {
714 cval |= UART_LCR_PARITY;
715 bits++;
717 if (!(cflag & PARODD))
718 cval |= UART_LCR_EPAR;
719 #ifdef CMSPAR
720 if (cflag & CMSPAR)
721 cval |= UART_LCR_SPAR;
722 #endif
724 /* Determine divisor based on baud rate */
725 baud = tty_get_baud_rate(info->tty);
726 if (!baud)
727 baud = 9600; /* B0 transition handled in rs_set_termios */
728 baud_base = info->state->baud_base;
729 if (baud == 38400 &&
730 ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
731 quot = info->state->custom_divisor;
732 else {
733 if (baud == 134)
734 /* Special case since 134 is really 134.5 */
735 quot = (2*baud_base / 269);
736 else if (baud)
737 quot = baud_base / baud;
739 /* If the quotient is zero refuse the change */
740 if (!quot && old_termios) {
741 /* FIXME: Will need updating for new tty in the end */
742 info->tty->termios->c_cflag &= ~CBAUD;
743 info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
744 baud = tty_get_baud_rate(info->tty);
745 if (!baud)
746 baud = 9600;
747 if (baud == 38400 &&
748 ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
749 quot = info->state->custom_divisor;
750 else {
751 if (baud == 134)
752 /* Special case since 134 is really 134.5 */
753 quot = (2*baud_base / 269);
754 else if (baud)
755 quot = baud_base / baud;
758 /* As a last resort, if the quotient is zero, default to 9600 bps */
759 if (!quot)
760 quot = baud_base / 9600;
761 info->quot = quot;
762 info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
763 info->timeout += HZ/50; /* Add .02 seconds of slop */
765 /* CTS flow control flag and modem status interrupts */
766 info->IER &= ~UART_IER_MSI;
767 if (info->flags & ASYNC_HARDPPS_CD)
768 info->IER |= UART_IER_MSI;
769 if (cflag & CRTSCTS) {
770 info->flags |= ASYNC_CTS_FLOW;
771 info->IER |= UART_IER_MSI;
772 } else
773 info->flags &= ~ASYNC_CTS_FLOW;
774 if (cflag & CLOCAL)
775 info->flags &= ~ASYNC_CHECK_CD;
776 else {
777 info->flags |= ASYNC_CHECK_CD;
778 info->IER |= UART_IER_MSI;
780 /* TBD:
781 * Does clearing IER_MSI imply that we should disable the VBL interrupt ?
785 * Set up parity check flag
788 info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
789 if (I_INPCK(info->tty))
790 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
791 if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
792 info->read_status_mask |= UART_LSR_BI;
795 * Characters to ignore
797 info->ignore_status_mask = 0;
798 if (I_IGNPAR(info->tty))
799 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
800 if (I_IGNBRK(info->tty)) {
801 info->ignore_status_mask |= UART_LSR_BI;
803 * If we're ignore parity and break indicators, ignore
804 * overruns too. (For real raw support).
806 if (I_IGNPAR(info->tty))
807 info->ignore_status_mask |= UART_LSR_OE;
810 * !!! ignore all characters if CREAD is not set
812 if ((cflag & CREAD) == 0)
813 info->ignore_status_mask |= UART_LSR_DR;
814 local_irq_save(flags);
817 short serper;
819 /* Set up the baud rate */
820 serper = quot - 1;
822 /* Enable or disable parity bit */
824 if(cval & UART_LCR_PARITY)
825 serper |= (SERPER_PARENB);
827 custom.serper = serper;
828 mb();
831 info->LCR = cval; /* Save LCR */
832 local_irq_restore(flags);
835 static int rs_put_char(struct tty_struct *tty, unsigned char ch)
837 struct async_struct *info;
838 unsigned long flags;
840 info = tty->driver_data;
842 if (serial_paranoia_check(info, tty->name, "rs_put_char"))
843 return 0;
845 if (!info->xmit.buf)
846 return 0;
848 local_irq_save(flags);
849 if (CIRC_SPACE(info->xmit.head,
850 info->xmit.tail,
851 SERIAL_XMIT_SIZE) == 0) {
852 local_irq_restore(flags);
853 return 0;
856 info->xmit.buf[info->xmit.head++] = ch;
857 info->xmit.head &= SERIAL_XMIT_SIZE-1;
858 local_irq_restore(flags);
859 return 1;
862 static void rs_flush_chars(struct tty_struct *tty)
864 struct async_struct *info = tty->driver_data;
865 unsigned long flags;
867 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
868 return;
870 if (info->xmit.head == info->xmit.tail
871 || tty->stopped
872 || tty->hw_stopped
873 || !info->xmit.buf)
874 return;
876 local_irq_save(flags);
877 info->IER |= UART_IER_THRI;
878 custom.intena = IF_SETCLR | IF_TBE;
879 mb();
880 /* set a pending Tx Interrupt, transmitter should restart now */
881 custom.intreq = IF_SETCLR | IF_TBE;
882 mb();
883 local_irq_restore(flags);
886 static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
888 int c, ret = 0;
889 struct async_struct *info;
890 unsigned long flags;
892 info = tty->driver_data;
894 if (serial_paranoia_check(info, tty->name, "rs_write"))
895 return 0;
897 if (!info->xmit.buf)
898 return 0;
900 local_irq_save(flags);
901 while (1) {
902 c = CIRC_SPACE_TO_END(info->xmit.head,
903 info->xmit.tail,
904 SERIAL_XMIT_SIZE);
905 if (count < c)
906 c = count;
907 if (c <= 0) {
908 break;
910 memcpy(info->xmit.buf + info->xmit.head, buf, c);
911 info->xmit.head = ((info->xmit.head + c) &
912 (SERIAL_XMIT_SIZE-1));
913 buf += c;
914 count -= c;
915 ret += c;
917 local_irq_restore(flags);
919 if (info->xmit.head != info->xmit.tail
920 && !tty->stopped
921 && !tty->hw_stopped
922 && !(info->IER & UART_IER_THRI)) {
923 info->IER |= UART_IER_THRI;
924 local_irq_disable();
925 custom.intena = IF_SETCLR | IF_TBE;
926 mb();
927 /* set a pending Tx Interrupt, transmitter should restart now */
928 custom.intreq = IF_SETCLR | IF_TBE;
929 mb();
930 local_irq_restore(flags);
932 return ret;
935 static int rs_write_room(struct tty_struct *tty)
937 struct async_struct *info = tty->driver_data;
939 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
940 return 0;
941 return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
944 static int rs_chars_in_buffer(struct tty_struct *tty)
946 struct async_struct *info = tty->driver_data;
948 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
949 return 0;
950 return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
953 static void rs_flush_buffer(struct tty_struct *tty)
955 struct async_struct *info = tty->driver_data;
956 unsigned long flags;
958 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
959 return;
960 local_irq_save(flags);
961 info->xmit.head = info->xmit.tail = 0;
962 local_irq_restore(flags);
963 tty_wakeup(tty);
967 * This function is used to send a high-priority XON/XOFF character to
968 * the device
970 static void rs_send_xchar(struct tty_struct *tty, char ch)
972 struct async_struct *info = tty->driver_data;
973 unsigned long flags;
975 if (serial_paranoia_check(info, tty->name, "rs_send_char"))
976 return;
978 info->x_char = ch;
979 if (ch) {
980 /* Make sure transmit interrupts are on */
982 /* Check this ! */
983 local_irq_save(flags);
984 if(!(custom.intenar & IF_TBE)) {
985 custom.intena = IF_SETCLR | IF_TBE;
986 mb();
987 /* set a pending Tx Interrupt, transmitter should restart now */
988 custom.intreq = IF_SETCLR | IF_TBE;
989 mb();
991 local_irq_restore(flags);
993 info->IER |= UART_IER_THRI;
998 * ------------------------------------------------------------
999 * rs_throttle()
1001 * This routine is called by the upper-layer tty layer to signal that
1002 * incoming characters should be throttled.
1003 * ------------------------------------------------------------
1005 static void rs_throttle(struct tty_struct * tty)
1007 struct async_struct *info = tty->driver_data;
1008 unsigned long flags;
1009 #ifdef SERIAL_DEBUG_THROTTLE
1010 char buf[64];
1012 printk("throttle %s: %d....\n", tty_name(tty, buf),
1013 tty->ldisc.chars_in_buffer(tty));
1014 #endif
1016 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
1017 return;
1019 if (I_IXOFF(tty))
1020 rs_send_xchar(tty, STOP_CHAR(tty));
1022 if (tty->termios->c_cflag & CRTSCTS)
1023 info->MCR &= ~SER_RTS;
1025 local_irq_save(flags);
1026 rtsdtr_ctrl(info->MCR);
1027 local_irq_restore(flags);
1030 static void rs_unthrottle(struct tty_struct * tty)
1032 struct async_struct *info = tty->driver_data;
1033 unsigned long flags;
1034 #ifdef SERIAL_DEBUG_THROTTLE
1035 char buf[64];
1037 printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1038 tty->ldisc.chars_in_buffer(tty));
1039 #endif
1041 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1042 return;
1044 if (I_IXOFF(tty)) {
1045 if (info->x_char)
1046 info->x_char = 0;
1047 else
1048 rs_send_xchar(tty, START_CHAR(tty));
1050 if (tty->termios->c_cflag & CRTSCTS)
1051 info->MCR |= SER_RTS;
1052 local_irq_save(flags);
1053 rtsdtr_ctrl(info->MCR);
1054 local_irq_restore(flags);
1058 * ------------------------------------------------------------
1059 * rs_ioctl() and friends
1060 * ------------------------------------------------------------
1063 static int get_serial_info(struct async_struct * info,
1064 struct serial_struct __user * retinfo)
1066 struct serial_struct tmp;
1067 struct serial_state *state = info->state;
1069 if (!retinfo)
1070 return -EFAULT;
1071 memset(&tmp, 0, sizeof(tmp));
1072 tty_lock();
1073 tmp.type = state->type;
1074 tmp.line = state->line;
1075 tmp.port = state->port;
1076 tmp.irq = state->irq;
1077 tmp.flags = state->flags;
1078 tmp.xmit_fifo_size = state->xmit_fifo_size;
1079 tmp.baud_base = state->baud_base;
1080 tmp.close_delay = state->close_delay;
1081 tmp.closing_wait = state->closing_wait;
1082 tmp.custom_divisor = state->custom_divisor;
1083 tty_unlock();
1084 if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1085 return -EFAULT;
1086 return 0;
1089 static int set_serial_info(struct async_struct * info,
1090 struct serial_struct __user * new_info)
1092 struct serial_struct new_serial;
1093 struct serial_state old_state, *state;
1094 unsigned int change_irq,change_port;
1095 int retval = 0;
1097 if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1098 return -EFAULT;
1100 tty_lock();
1101 state = info->state;
1102 old_state = *state;
1104 change_irq = new_serial.irq != state->irq;
1105 change_port = (new_serial.port != state->port);
1106 if(change_irq || change_port || (new_serial.xmit_fifo_size != state->xmit_fifo_size)) {
1107 tty_unlock();
1108 return -EINVAL;
1111 if (!serial_isroot()) {
1112 if ((new_serial.baud_base != state->baud_base) ||
1113 (new_serial.close_delay != state->close_delay) ||
1114 (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
1115 ((new_serial.flags & ~ASYNC_USR_MASK) !=
1116 (state->flags & ~ASYNC_USR_MASK)))
1117 return -EPERM;
1118 state->flags = ((state->flags & ~ASYNC_USR_MASK) |
1119 (new_serial.flags & ASYNC_USR_MASK));
1120 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
1121 (new_serial.flags & ASYNC_USR_MASK));
1122 state->custom_divisor = new_serial.custom_divisor;
1123 goto check_and_exit;
1126 if (new_serial.baud_base < 9600) {
1127 tty_unlock();
1128 return -EINVAL;
1132 * OK, past this point, all the error checking has been done.
1133 * At this point, we start making changes.....
1136 state->baud_base = new_serial.baud_base;
1137 state->flags = ((state->flags & ~ASYNC_FLAGS) |
1138 (new_serial.flags & ASYNC_FLAGS));
1139 info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) |
1140 (info->flags & ASYNC_INTERNAL_FLAGS));
1141 state->custom_divisor = new_serial.custom_divisor;
1142 state->close_delay = new_serial.close_delay * HZ/100;
1143 state->closing_wait = new_serial.closing_wait * HZ/100;
1144 info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1146 check_and_exit:
1147 if (info->flags & ASYNC_INITIALIZED) {
1148 if (((old_state.flags & ASYNC_SPD_MASK) !=
1149 (state->flags & ASYNC_SPD_MASK)) ||
1150 (old_state.custom_divisor != state->custom_divisor)) {
1151 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1152 info->tty->alt_speed = 57600;
1153 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1154 info->tty->alt_speed = 115200;
1155 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1156 info->tty->alt_speed = 230400;
1157 if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1158 info->tty->alt_speed = 460800;
1159 change_speed(info, NULL);
1161 } else
1162 retval = startup(info);
1163 tty_unlock();
1164 return retval;
1169 * get_lsr_info - get line status register info
1171 * Purpose: Let user call ioctl() to get info when the UART physically
1172 * is emptied. On bus types like RS485, the transmitter must
1173 * release the bus after transmitting. This must be done when
1174 * the transmit shift register is empty, not be done when the
1175 * transmit holding register is empty. This functionality
1176 * allows an RS485 driver to be written in user space.
1178 static int get_lsr_info(struct async_struct * info, unsigned int __user *value)
1180 unsigned char status;
1181 unsigned int result;
1182 unsigned long flags;
1184 local_irq_save(flags);
1185 status = custom.serdatr;
1186 mb();
1187 local_irq_restore(flags);
1188 result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
1189 if (copy_to_user(value, &result, sizeof(int)))
1190 return -EFAULT;
1191 return 0;
1195 static int rs_tiocmget(struct tty_struct *tty)
1197 struct async_struct * info = tty->driver_data;
1198 unsigned char control, status;
1199 unsigned long flags;
1201 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1202 return -ENODEV;
1203 if (tty->flags & (1 << TTY_IO_ERROR))
1204 return -EIO;
1206 control = info->MCR;
1207 local_irq_save(flags);
1208 status = ciab.pra;
1209 local_irq_restore(flags);
1210 return ((control & SER_RTS) ? TIOCM_RTS : 0)
1211 | ((control & SER_DTR) ? TIOCM_DTR : 0)
1212 | (!(status & SER_DCD) ? TIOCM_CAR : 0)
1213 | (!(status & SER_DSR) ? TIOCM_DSR : 0)
1214 | (!(status & SER_CTS) ? TIOCM_CTS : 0);
1217 static int rs_tiocmset(struct tty_struct *tty, unsigned int set,
1218 unsigned int clear)
1220 struct async_struct * info = tty->driver_data;
1221 unsigned long flags;
1223 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1224 return -ENODEV;
1225 if (tty->flags & (1 << TTY_IO_ERROR))
1226 return -EIO;
1228 local_irq_save(flags);
1229 if (set & TIOCM_RTS)
1230 info->MCR |= SER_RTS;
1231 if (set & TIOCM_DTR)
1232 info->MCR |= SER_DTR;
1233 if (clear & TIOCM_RTS)
1234 info->MCR &= ~SER_RTS;
1235 if (clear & TIOCM_DTR)
1236 info->MCR &= ~SER_DTR;
1237 rtsdtr_ctrl(info->MCR);
1238 local_irq_restore(flags);
1239 return 0;
1243 * rs_break() --- routine which turns the break handling on or off
1245 static int rs_break(struct tty_struct *tty, int break_state)
1247 struct async_struct * info = tty->driver_data;
1248 unsigned long flags;
1250 if (serial_paranoia_check(info, tty->name, "rs_break"))
1251 return -EINVAL;
1253 local_irq_save(flags);
1254 if (break_state == -1)
1255 custom.adkcon = AC_SETCLR | AC_UARTBRK;
1256 else
1257 custom.adkcon = AC_UARTBRK;
1258 mb();
1259 local_irq_restore(flags);
1260 return 0;
1264 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1265 * Return: write counters to the user passed counter struct
1266 * NB: both 1->0 and 0->1 transitions are counted except for
1267 * RI where only 0->1 is counted.
1269 static int rs_get_icount(struct tty_struct *tty,
1270 struct serial_icounter_struct *icount)
1272 struct async_struct *info = tty->driver_data;
1273 struct async_icount cnow;
1274 unsigned long flags;
1276 local_irq_save(flags);
1277 cnow = info->state->icount;
1278 local_irq_restore(flags);
1279 icount->cts = cnow.cts;
1280 icount->dsr = cnow.dsr;
1281 icount->rng = cnow.rng;
1282 icount->dcd = cnow.dcd;
1283 icount->rx = cnow.rx;
1284 icount->tx = cnow.tx;
1285 icount->frame = cnow.frame;
1286 icount->overrun = cnow.overrun;
1287 icount->parity = cnow.parity;
1288 icount->brk = cnow.brk;
1289 icount->buf_overrun = cnow.buf_overrun;
1291 return 0;
1294 static int rs_ioctl(struct tty_struct *tty,
1295 unsigned int cmd, unsigned long arg)
1297 struct async_struct * info = tty->driver_data;
1298 struct async_icount cprev, cnow; /* kernel counter temps */
1299 void __user *argp = (void __user *)arg;
1300 unsigned long flags;
1302 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1303 return -ENODEV;
1305 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1306 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
1307 (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1308 if (tty->flags & (1 << TTY_IO_ERROR))
1309 return -EIO;
1312 switch (cmd) {
1313 case TIOCGSERIAL:
1314 return get_serial_info(info, argp);
1315 case TIOCSSERIAL:
1316 return set_serial_info(info, argp);
1317 case TIOCSERCONFIG:
1318 return 0;
1320 case TIOCSERGETLSR: /* Get line status register */
1321 return get_lsr_info(info, argp);
1323 case TIOCSERGSTRUCT:
1324 if (copy_to_user(argp,
1325 info, sizeof(struct async_struct)))
1326 return -EFAULT;
1327 return 0;
1330 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1331 * - mask passed in arg for lines of interest
1332 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1333 * Caller should use TIOCGICOUNT to see which one it was
1335 case TIOCMIWAIT:
1336 local_irq_save(flags);
1337 /* note the counters on entry */
1338 cprev = info->state->icount;
1339 local_irq_restore(flags);
1340 while (1) {
1341 interruptible_sleep_on(&info->delta_msr_wait);
1342 /* see if a signal did it */
1343 if (signal_pending(current))
1344 return -ERESTARTSYS;
1345 local_irq_save(flags);
1346 cnow = info->state->icount; /* atomic copy */
1347 local_irq_restore(flags);
1348 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
1349 cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1350 return -EIO; /* no change => error */
1351 if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1352 ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1353 ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
1354 ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1355 return 0;
1357 cprev = cnow;
1359 /* NOTREACHED */
1361 case TIOCSERGWILD:
1362 case TIOCSERSWILD:
1363 /* "setserial -W" is called in Debian boot */
1364 printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
1365 return 0;
1367 default:
1368 return -ENOIOCTLCMD;
1370 return 0;
1373 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
1375 struct async_struct *info = tty->driver_data;
1376 unsigned long flags;
1377 unsigned int cflag = tty->termios->c_cflag;
1379 change_speed(info, old_termios);
1381 /* Handle transition to B0 status */
1382 if ((old_termios->c_cflag & CBAUD) &&
1383 !(cflag & CBAUD)) {
1384 info->MCR &= ~(SER_DTR|SER_RTS);
1385 local_irq_save(flags);
1386 rtsdtr_ctrl(info->MCR);
1387 local_irq_restore(flags);
1390 /* Handle transition away from B0 status */
1391 if (!(old_termios->c_cflag & CBAUD) &&
1392 (cflag & CBAUD)) {
1393 info->MCR |= SER_DTR;
1394 if (!(tty->termios->c_cflag & CRTSCTS) ||
1395 !test_bit(TTY_THROTTLED, &tty->flags)) {
1396 info->MCR |= SER_RTS;
1398 local_irq_save(flags);
1399 rtsdtr_ctrl(info->MCR);
1400 local_irq_restore(flags);
1403 /* Handle turning off CRTSCTS */
1404 if ((old_termios->c_cflag & CRTSCTS) &&
1405 !(tty->termios->c_cflag & CRTSCTS)) {
1406 tty->hw_stopped = 0;
1407 rs_start(tty);
1410 #if 0
1412 * No need to wake up processes in open wait, since they
1413 * sample the CLOCAL flag once, and don't recheck it.
1414 * XXX It's not clear whether the current behavior is correct
1415 * or not. Hence, this may change.....
1417 if (!(old_termios->c_cflag & CLOCAL) &&
1418 (tty->termios->c_cflag & CLOCAL))
1419 wake_up_interruptible(&info->open_wait);
1420 #endif
1424 * ------------------------------------------------------------
1425 * rs_close()
1427 * This routine is called when the serial port gets closed. First, we
1428 * wait for the last remaining data to be sent. Then, we unlink its
1429 * async structure from the interrupt chain if necessary, and we free
1430 * that IRQ if nothing is left in the chain.
1431 * ------------------------------------------------------------
1433 static void rs_close(struct tty_struct *tty, struct file * filp)
1435 struct async_struct * info = tty->driver_data;
1436 struct serial_state *state;
1437 unsigned long flags;
1439 if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1440 return;
1442 state = info->state;
1444 local_irq_save(flags);
1446 if (tty_hung_up_p(filp)) {
1447 DBG_CNT("before DEC-hung");
1448 local_irq_restore(flags);
1449 return;
1452 #ifdef SERIAL_DEBUG_OPEN
1453 printk("rs_close ttys%d, count = %d\n", info->line, state->count);
1454 #endif
1455 if ((tty->count == 1) && (state->count != 1)) {
1457 * Uh, oh. tty->count is 1, which means that the tty
1458 * structure will be freed. state->count should always
1459 * be one in these conditions. If it's greater than
1460 * one, we've got real problems, since it means the
1461 * serial port won't be shutdown.
1463 printk("rs_close: bad serial port count; tty->count is 1, "
1464 "state->count is %d\n", state->count);
1465 state->count = 1;
1467 if (--state->count < 0) {
1468 printk("rs_close: bad serial port count for ttys%d: %d\n",
1469 info->line, state->count);
1470 state->count = 0;
1472 if (state->count) {
1473 DBG_CNT("before DEC-2");
1474 local_irq_restore(flags);
1475 return;
1477 info->flags |= ASYNC_CLOSING;
1479 * Now we wait for the transmit buffer to clear; and we notify
1480 * the line discipline to only process XON/XOFF characters.
1482 tty->closing = 1;
1483 if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1484 tty_wait_until_sent(tty, info->closing_wait);
1486 * At this point we stop accepting input. To do this, we
1487 * disable the receive line status interrupts, and tell the
1488 * interrupt driver to stop checking the data ready bit in the
1489 * line status register.
1491 info->read_status_mask &= ~UART_LSR_DR;
1492 if (info->flags & ASYNC_INITIALIZED) {
1493 /* disable receive interrupts */
1494 custom.intena = IF_RBF;
1495 mb();
1496 /* clear any pending receive interrupt */
1497 custom.intreq = IF_RBF;
1498 mb();
1501 * Before we drop DTR, make sure the UART transmitter
1502 * has completely drained; this is especially
1503 * important if there is a transmit FIFO!
1505 rs_wait_until_sent(tty, info->timeout);
1507 shutdown(info);
1508 rs_flush_buffer(tty);
1510 tty_ldisc_flush(tty);
1511 tty->closing = 0;
1512 info->event = 0;
1513 info->tty = NULL;
1514 if (info->blocked_open) {
1515 if (info->close_delay) {
1516 msleep_interruptible(jiffies_to_msecs(info->close_delay));
1518 wake_up_interruptible(&info->open_wait);
1520 info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
1521 wake_up_interruptible(&info->close_wait);
1522 local_irq_restore(flags);
1526 * rs_wait_until_sent() --- wait until the transmitter is empty
1528 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1530 struct async_struct * info = tty->driver_data;
1531 unsigned long orig_jiffies, char_time;
1532 int lsr;
1534 if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
1535 return;
1537 if (info->xmit_fifo_size == 0)
1538 return; /* Just in case.... */
1540 orig_jiffies = jiffies;
1543 * Set the check interval to be 1/5 of the estimated time to
1544 * send a single character, and make it at least 1. The check
1545 * interval should also be less than the timeout.
1547 * Note: we have to use pretty tight timings here to satisfy
1548 * the NIST-PCTS.
1550 char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
1551 char_time = char_time / 5;
1552 if (char_time == 0)
1553 char_time = 1;
1554 if (timeout)
1555 char_time = min_t(unsigned long, char_time, timeout);
1557 * If the transmitter hasn't cleared in twice the approximate
1558 * amount of time to send the entire FIFO, it probably won't
1559 * ever clear. This assumes the UART isn't doing flow
1560 * control, which is currently the case. Hence, if it ever
1561 * takes longer than info->timeout, this is probably due to a
1562 * UART bug of some kind. So, we clamp the timeout parameter at
1563 * 2*info->timeout.
1565 if (!timeout || timeout > 2*info->timeout)
1566 timeout = 2*info->timeout;
1567 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1568 printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
1569 printk("jiff=%lu...", jiffies);
1570 #endif
1571 while(!((lsr = custom.serdatr) & SDR_TSRE)) {
1572 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1573 printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
1574 #endif
1575 msleep_interruptible(jiffies_to_msecs(char_time));
1576 if (signal_pending(current))
1577 break;
1578 if (timeout && time_after(jiffies, orig_jiffies + timeout))
1579 break;
1581 __set_current_state(TASK_RUNNING);
1583 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1584 printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1585 #endif
1589 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1591 static void rs_hangup(struct tty_struct *tty)
1593 struct async_struct * info = tty->driver_data;
1594 struct serial_state *state = info->state;
1596 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1597 return;
1599 state = info->state;
1601 rs_flush_buffer(tty);
1602 shutdown(info);
1603 info->event = 0;
1604 state->count = 0;
1605 info->flags &= ~ASYNC_NORMAL_ACTIVE;
1606 info->tty = NULL;
1607 wake_up_interruptible(&info->open_wait);
1611 * ------------------------------------------------------------
1612 * rs_open() and friends
1613 * ------------------------------------------------------------
1615 static int block_til_ready(struct tty_struct *tty, struct file * filp,
1616 struct async_struct *info)
1618 #ifdef DECLARE_WAITQUEUE
1619 DECLARE_WAITQUEUE(wait, current);
1620 #else
1621 struct wait_queue wait = { current, NULL };
1622 #endif
1623 struct serial_state *state = info->state;
1624 int retval;
1625 int do_clocal = 0, extra_count = 0;
1626 unsigned long flags;
1629 * If the device is in the middle of being closed, then block
1630 * until it's done, and then try again.
1632 if (tty_hung_up_p(filp) ||
1633 (info->flags & ASYNC_CLOSING)) {
1634 if (info->flags & ASYNC_CLOSING)
1635 interruptible_sleep_on(&info->close_wait);
1636 #ifdef SERIAL_DO_RESTART
1637 return ((info->flags & ASYNC_HUP_NOTIFY) ?
1638 -EAGAIN : -ERESTARTSYS);
1639 #else
1640 return -EAGAIN;
1641 #endif
1645 * If non-blocking mode is set, or the port is not enabled,
1646 * then make the check up front and then exit.
1648 if ((filp->f_flags & O_NONBLOCK) ||
1649 (tty->flags & (1 << TTY_IO_ERROR))) {
1650 info->flags |= ASYNC_NORMAL_ACTIVE;
1651 return 0;
1654 if (tty->termios->c_cflag & CLOCAL)
1655 do_clocal = 1;
1658 * Block waiting for the carrier detect and the line to become
1659 * free (i.e., not in use by the callout). While we are in
1660 * this loop, state->count is dropped by one, so that
1661 * rs_close() knows when to free things. We restore it upon
1662 * exit, either normal or abnormal.
1664 retval = 0;
1665 add_wait_queue(&info->open_wait, &wait);
1666 #ifdef SERIAL_DEBUG_OPEN
1667 printk("block_til_ready before block: ttys%d, count = %d\n",
1668 state->line, state->count);
1669 #endif
1670 local_irq_save(flags);
1671 if (!tty_hung_up_p(filp)) {
1672 extra_count = 1;
1673 state->count--;
1675 local_irq_restore(flags);
1676 info->blocked_open++;
1677 while (1) {
1678 local_irq_save(flags);
1679 if (tty->termios->c_cflag & CBAUD)
1680 rtsdtr_ctrl(SER_DTR|SER_RTS);
1681 local_irq_restore(flags);
1682 set_current_state(TASK_INTERRUPTIBLE);
1683 if (tty_hung_up_p(filp) ||
1684 !(info->flags & ASYNC_INITIALIZED)) {
1685 #ifdef SERIAL_DO_RESTART
1686 if (info->flags & ASYNC_HUP_NOTIFY)
1687 retval = -EAGAIN;
1688 else
1689 retval = -ERESTARTSYS;
1690 #else
1691 retval = -EAGAIN;
1692 #endif
1693 break;
1695 if (!(info->flags & ASYNC_CLOSING) &&
1696 (do_clocal || (!(ciab.pra & SER_DCD)) ))
1697 break;
1698 if (signal_pending(current)) {
1699 retval = -ERESTARTSYS;
1700 break;
1702 #ifdef SERIAL_DEBUG_OPEN
1703 printk("block_til_ready blocking: ttys%d, count = %d\n",
1704 info->line, state->count);
1705 #endif
1706 tty_unlock();
1707 schedule();
1708 tty_lock();
1710 __set_current_state(TASK_RUNNING);
1711 remove_wait_queue(&info->open_wait, &wait);
1712 if (extra_count)
1713 state->count++;
1714 info->blocked_open--;
1715 #ifdef SERIAL_DEBUG_OPEN
1716 printk("block_til_ready after blocking: ttys%d, count = %d\n",
1717 info->line, state->count);
1718 #endif
1719 if (retval)
1720 return retval;
1721 info->flags |= ASYNC_NORMAL_ACTIVE;
1722 return 0;
1725 static int get_async_struct(int line, struct async_struct **ret_info)
1727 struct async_struct *info;
1728 struct serial_state *sstate;
1730 sstate = rs_table + line;
1731 sstate->count++;
1732 if (sstate->info) {
1733 *ret_info = sstate->info;
1734 return 0;
1736 info = kzalloc(sizeof(struct async_struct), GFP_KERNEL);
1737 if (!info) {
1738 sstate->count--;
1739 return -ENOMEM;
1741 #ifdef DECLARE_WAITQUEUE
1742 init_waitqueue_head(&info->open_wait);
1743 init_waitqueue_head(&info->close_wait);
1744 init_waitqueue_head(&info->delta_msr_wait);
1745 #endif
1746 info->magic = SERIAL_MAGIC;
1747 info->port = sstate->port;
1748 info->flags = sstate->flags;
1749 info->xmit_fifo_size = sstate->xmit_fifo_size;
1750 info->line = line;
1751 tasklet_init(&info->tlet, do_softint, (unsigned long)info);
1752 info->state = sstate;
1753 if (sstate->info) {
1754 kfree(info);
1755 *ret_info = sstate->info;
1756 return 0;
1758 *ret_info = sstate->info = info;
1759 return 0;
1763 * This routine is called whenever a serial port is opened. It
1764 * enables interrupts for a serial port, linking in its async structure into
1765 * the IRQ chain. It also performs the serial-specific
1766 * initialization for the tty structure.
1768 static int rs_open(struct tty_struct *tty, struct file * filp)
1770 struct async_struct *info;
1771 int retval, line;
1773 line = tty->index;
1774 if ((line < 0) || (line >= NR_PORTS)) {
1775 return -ENODEV;
1777 retval = get_async_struct(line, &info);
1778 if (retval) {
1779 return retval;
1781 tty->driver_data = info;
1782 info->tty = tty;
1783 if (serial_paranoia_check(info, tty->name, "rs_open"))
1784 return -ENODEV;
1786 #ifdef SERIAL_DEBUG_OPEN
1787 printk("rs_open %s, count = %d\n", tty->name, info->state->count);
1788 #endif
1789 info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1792 * If the port is the middle of closing, bail out now
1794 if (tty_hung_up_p(filp) ||
1795 (info->flags & ASYNC_CLOSING)) {
1796 if (info->flags & ASYNC_CLOSING)
1797 interruptible_sleep_on(&info->close_wait);
1798 #ifdef SERIAL_DO_RESTART
1799 return ((info->flags & ASYNC_HUP_NOTIFY) ?
1800 -EAGAIN : -ERESTARTSYS);
1801 #else
1802 return -EAGAIN;
1803 #endif
1807 * Start up serial port
1809 retval = startup(info);
1810 if (retval) {
1811 return retval;
1814 retval = block_til_ready(tty, filp, info);
1815 if (retval) {
1816 #ifdef SERIAL_DEBUG_OPEN
1817 printk("rs_open returning after block_til_ready with %d\n",
1818 retval);
1819 #endif
1820 return retval;
1823 #ifdef SERIAL_DEBUG_OPEN
1824 printk("rs_open %s successful...", tty->name);
1825 #endif
1826 return 0;
1830 * /proc fs routines....
1833 static inline void line_info(struct seq_file *m, struct serial_state *state)
1835 struct async_struct *info = state->info, scr_info;
1836 char stat_buf[30], control, status;
1837 unsigned long flags;
1839 seq_printf(m, "%d: uart:amiga_builtin",state->line);
1842 * Figure out the current RS-232 lines
1844 if (!info) {
1845 info = &scr_info; /* This is just for serial_{in,out} */
1847 info->magic = SERIAL_MAGIC;
1848 info->flags = state->flags;
1849 info->quot = 0;
1850 info->tty = NULL;
1852 local_irq_save(flags);
1853 status = ciab.pra;
1854 control = info ? info->MCR : status;
1855 local_irq_restore(flags);
1857 stat_buf[0] = 0;
1858 stat_buf[1] = 0;
1859 if(!(control & SER_RTS))
1860 strcat(stat_buf, "|RTS");
1861 if(!(status & SER_CTS))
1862 strcat(stat_buf, "|CTS");
1863 if(!(control & SER_DTR))
1864 strcat(stat_buf, "|DTR");
1865 if(!(status & SER_DSR))
1866 strcat(stat_buf, "|DSR");
1867 if(!(status & SER_DCD))
1868 strcat(stat_buf, "|CD");
1870 if (info->quot) {
1871 seq_printf(m, " baud:%d", state->baud_base / info->quot);
1874 seq_printf(m, " tx:%d rx:%d", state->icount.tx, state->icount.rx);
1876 if (state->icount.frame)
1877 seq_printf(m, " fe:%d", state->icount.frame);
1879 if (state->icount.parity)
1880 seq_printf(m, " pe:%d", state->icount.parity);
1882 if (state->icount.brk)
1883 seq_printf(m, " brk:%d", state->icount.brk);
1885 if (state->icount.overrun)
1886 seq_printf(m, " oe:%d", state->icount.overrun);
1889 * Last thing is the RS-232 status lines
1891 seq_printf(m, " %s\n", stat_buf+1);
1894 static int rs_proc_show(struct seq_file *m, void *v)
1896 seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
1897 line_info(m, &rs_table[0]);
1898 return 0;
1901 static int rs_proc_open(struct inode *inode, struct file *file)
1903 return single_open(file, rs_proc_show, NULL);
1906 static const struct file_operations rs_proc_fops = {
1907 .owner = THIS_MODULE,
1908 .open = rs_proc_open,
1909 .read = seq_read,
1910 .llseek = seq_lseek,
1911 .release = single_release,
1915 * ---------------------------------------------------------------------
1916 * rs_init() and friends
1918 * rs_init() is called at boot-time to initialize the serial driver.
1919 * ---------------------------------------------------------------------
1923 * This routine prints out the appropriate serial driver version
1924 * number, and identifies which options were configured into this
1925 * driver.
1927 static void show_serial_version(void)
1929 printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
1933 static const struct tty_operations serial_ops = {
1934 .open = rs_open,
1935 .close = rs_close,
1936 .write = rs_write,
1937 .put_char = rs_put_char,
1938 .flush_chars = rs_flush_chars,
1939 .write_room = rs_write_room,
1940 .chars_in_buffer = rs_chars_in_buffer,
1941 .flush_buffer = rs_flush_buffer,
1942 .ioctl = rs_ioctl,
1943 .throttle = rs_throttle,
1944 .unthrottle = rs_unthrottle,
1945 .set_termios = rs_set_termios,
1946 .stop = rs_stop,
1947 .start = rs_start,
1948 .hangup = rs_hangup,
1949 .break_ctl = rs_break,
1950 .send_xchar = rs_send_xchar,
1951 .wait_until_sent = rs_wait_until_sent,
1952 .tiocmget = rs_tiocmget,
1953 .tiocmset = rs_tiocmset,
1954 .get_icount = rs_get_icount,
1955 .proc_fops = &rs_proc_fops,
1959 * The serial driver boot-time initialization code!
1961 static int __init amiga_serial_probe(struct platform_device *pdev)
1963 unsigned long flags;
1964 struct serial_state * state;
1965 int error;
1967 serial_driver = alloc_tty_driver(1);
1968 if (!serial_driver)
1969 return -ENOMEM;
1971 IRQ_ports = NULL;
1973 show_serial_version();
1975 /* Initialize the tty_driver structure */
1977 serial_driver->owner = THIS_MODULE;
1978 serial_driver->driver_name = "amiserial";
1979 serial_driver->name = "ttyS";
1980 serial_driver->major = TTY_MAJOR;
1981 serial_driver->minor_start = 64;
1982 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1983 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1984 serial_driver->init_termios = tty_std_termios;
1985 serial_driver->init_termios.c_cflag =
1986 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1987 serial_driver->flags = TTY_DRIVER_REAL_RAW;
1988 tty_set_operations(serial_driver, &serial_ops);
1990 error = tty_register_driver(serial_driver);
1991 if (error)
1992 goto fail_put_tty_driver;
1994 state = rs_table;
1995 state->magic = SSTATE_MAGIC;
1996 state->port = (int)&custom.serdatr; /* Just to give it a value */
1997 state->line = 0;
1998 state->custom_divisor = 0;
1999 state->close_delay = 5*HZ/10;
2000 state->closing_wait = 30*HZ;
2001 state->icount.cts = state->icount.dsr =
2002 state->icount.rng = state->icount.dcd = 0;
2003 state->icount.rx = state->icount.tx = 0;
2004 state->icount.frame = state->icount.parity = 0;
2005 state->icount.overrun = state->icount.brk = 0;
2007 printk(KERN_INFO "ttyS%d is the amiga builtin serial port\n",
2008 state->line);
2010 /* Hardware set up */
2012 state->baud_base = amiga_colorclock;
2013 state->xmit_fifo_size = 1;
2015 /* set ISRs, and then disable the rx interrupts */
2016 error = request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
2017 if (error)
2018 goto fail_unregister;
2020 error = request_irq(IRQ_AMIGA_RBF, ser_rx_int, IRQF_DISABLED,
2021 "serial RX", state);
2022 if (error)
2023 goto fail_free_irq;
2025 local_irq_save(flags);
2027 /* turn off Rx and Tx interrupts */
2028 custom.intena = IF_RBF | IF_TBE;
2029 mb();
2031 /* clear any pending interrupt */
2032 custom.intreq = IF_RBF | IF_TBE;
2033 mb();
2035 local_irq_restore(flags);
2038 * set the appropriate directions for the modem control flags,
2039 * and clear RTS and DTR
2041 ciab.ddra |= (SER_DTR | SER_RTS); /* outputs */
2042 ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR); /* inputs */
2044 platform_set_drvdata(pdev, state);
2046 return 0;
2048 fail_free_irq:
2049 free_irq(IRQ_AMIGA_TBE, state);
2050 fail_unregister:
2051 tty_unregister_driver(serial_driver);
2052 fail_put_tty_driver:
2053 put_tty_driver(serial_driver);
2054 return error;
2057 static int __exit amiga_serial_remove(struct platform_device *pdev)
2059 int error;
2060 struct serial_state *state = platform_get_drvdata(pdev);
2061 struct async_struct *info = state->info;
2063 /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
2064 tasklet_kill(&info->tlet);
2065 if ((error = tty_unregister_driver(serial_driver)))
2066 printk("SERIAL: failed to unregister serial driver (%d)\n",
2067 error);
2068 put_tty_driver(serial_driver);
2070 rs_table[0].info = NULL;
2071 kfree(info);
2073 free_irq(IRQ_AMIGA_TBE, rs_table);
2074 free_irq(IRQ_AMIGA_RBF, rs_table);
2076 platform_set_drvdata(pdev, NULL);
2078 return error;
2081 static struct platform_driver amiga_serial_driver = {
2082 .remove = __exit_p(amiga_serial_remove),
2083 .driver = {
2084 .name = "amiga-serial",
2085 .owner = THIS_MODULE,
2089 static int __init amiga_serial_init(void)
2091 return platform_driver_probe(&amiga_serial_driver, amiga_serial_probe);
2094 module_init(amiga_serial_init);
2096 static void __exit amiga_serial_exit(void)
2098 platform_driver_unregister(&amiga_serial_driver);
2101 module_exit(amiga_serial_exit);
2104 #if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE)
2107 * ------------------------------------------------------------
2108 * Serial console driver
2109 * ------------------------------------------------------------
2112 static void amiga_serial_putc(char c)
2114 custom.serdat = (unsigned char)c | 0x100;
2115 while (!(custom.serdatr & 0x2000))
2116 barrier();
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.
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,
2156 * Register console.
2158 static int __init amiserial_console_init(void)
2160 register_console(&sercons);
2161 return 0;
2163 console_initcall(amiserial_console_init);
2165 #endif /* CONFIG_SERIAL_CONSOLE && !MODULE */
2167 MODULE_LICENSE("GPL");
2168 MODULE_ALIAS("platform:amiga-serial");