2 * $Id: ctctty.c,v 1.26 2004/08/04 11:06:55 mschwide Exp $
4 * CTC / ESCON network driver, tty interface.
6 * Copyright (C) 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation
7 * Author(s): Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2, or (at your option)
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #include <linux/config.h>
26 #include <linux/module.h>
27 #include <linux/tty.h>
28 #include <linux/serial_reg.h>
29 #include <linux/interrupt.h>
30 #include <linux/delay.h>
31 #include <asm/uaccess.h>
32 #include <linux/devfs_fs_kernel.h>
36 #define CTC_TTY_MAJOR 43
37 #define CTC_TTY_MAX_DEVICES 64
39 #define CTC_ASYNC_MAGIC 0x49344C01 /* for paranoia-checking */
40 #define CTC_ASYNC_INITIALIZED 0x80000000 /* port was initialized */
41 #define CTC_ASYNC_NORMAL_ACTIVE 0x20000000 /* Normal device active */
42 #define CTC_ASYNC_CLOSING 0x08000000 /* Serial port is closing */
43 #define CTC_ASYNC_CTS_FLOW 0x04000000 /* Do CTS flow control */
44 #define CTC_ASYNC_CHECK_CD 0x02000000 /* i.e., CLOCAL */
45 #define CTC_ASYNC_HUP_NOTIFY 0x0001 /* Notify tty on hangups/closes */
46 #define CTC_ASYNC_NETDEV_OPEN 0x0002 /* Underlying netdev is open */
47 #define CTC_ASYNC_TX_LINESTAT 0x0004 /* Must send line status */
48 #define CTC_ASYNC_SPLIT_TERMIOS 0x0008 /* Sep. termios for dialin/out */
49 #define CTC_TTY_XMIT_SIZE 1024 /* Default bufsize for write */
50 #define CTC_SERIAL_XMIT_MAX 4000 /* Maximum bufsize for write */
52 /* Private data (similar to async_struct in <linux/serial.h>) */
55 int flags; /* defined in tty.h */
56 int mcr; /* Modem control register */
57 int msr; /* Modem status register */
58 int lsr; /* Line status register */
60 int count; /* # of fd on device */
61 int blocked_open; /* # of blocked opens */
62 struct net_device *netdev;
63 struct sk_buff_head tx_queue; /* transmit queue */
64 struct sk_buff_head rx_queue; /* receive queue */
65 struct tty_struct *tty; /* Pointer to corresponding tty */
66 wait_queue_head_t open_wait;
67 wait_queue_head_t close_wait;
68 struct semaphore write_sem;
69 struct tasklet_struct tasklet;
70 struct timer_list stoptimer;
73 /* Description of one CTC-tty */
75 struct tty_driver *ctc_tty_device; /* tty-device */
76 ctc_tty_info info[CTC_TTY_MAX_DEVICES]; /* Private data */
79 static ctc_tty_driver *driver;
81 /* Leave this unchanged unless you know what you do! */
82 #define MODEM_PARANOIA_CHECK
83 #define MODEM_DO_RESTART
85 #define CTC_TTY_NAME "ctctty"
87 static __u32 ctc_tty_magic = CTC_ASYNC_MAGIC;
88 static int ctc_tty_shuttingdown = 0;
90 static spinlock_t ctc_tty_lock;
92 /* ctc_tty_try_read() is called from within ctc_tty_rcv_skb()
93 * to stuff incoming data directly into a tty's flip-buffer. If the
94 * flip buffer is full, the packet gets queued up.
98 * 0 = Failure, data has to be buffered and later processed by
99 * ctc_tty_readmodem().
102 ctc_tty_try_read(ctc_tty_info * info, struct sk_buff *skb)
106 struct tty_struct *tty;
108 DBF_TEXT(trace, 5, __FUNCTION__);
109 if ((tty = info->tty)) {
110 if (info->mcr & UART_MCR_RTS) {
111 c = TTY_FLIPBUF_SIZE - tty->flip.count;
114 memcpy(tty->flip.char_buf_ptr, skb->data, len);
115 memset(tty->flip.flag_buf_ptr, 0, len);
116 tty->flip.count += len;
117 tty->flip.char_buf_ptr += len;
118 tty->flip.flag_buf_ptr += len;
119 tty_flip_buffer_push(tty);
128 /* ctc_tty_readmodem() is called periodically from within timer-interrupt.
129 * It tries getting received data from the receive queue an stuff it into
130 * the tty's flip-buffer.
133 ctc_tty_readmodem(ctc_tty_info *info)
136 struct tty_struct *tty;
138 DBF_TEXT(trace, 5, __FUNCTION__);
139 if ((tty = info->tty)) {
140 if (info->mcr & UART_MCR_RTS) {
141 int c = TTY_FLIPBUF_SIZE - tty->flip.count;
144 if ((c > 0) && (skb = skb_dequeue(&info->rx_queue))) {
148 memcpy(tty->flip.char_buf_ptr, skb->data, len);
150 memset(tty->flip.flag_buf_ptr, 0, len);
151 tty->flip.count += len;
152 tty->flip.char_buf_ptr += len;
153 tty->flip.flag_buf_ptr += len;
154 tty_flip_buffer_push(tty);
156 skb_queue_head(&info->rx_queue, skb);
159 ret = skb_queue_len(&info->rx_queue);
168 ctc_tty_setcarrier(struct net_device *netdev, int on)
172 DBF_TEXT(trace, 4, __FUNCTION__);
173 if ((!driver) || ctc_tty_shuttingdown)
175 for (i = 0; i < CTC_TTY_MAX_DEVICES; i++)
176 if (driver->info[i].netdev == netdev) {
177 ctc_tty_info *info = &driver->info[i];
179 info->msr |= UART_MSR_DCD;
181 info->msr &= ~UART_MSR_DCD;
182 if ((info->flags & CTC_ASYNC_CHECK_CD) && (!on))
183 tty_hangup(info->tty);
188 ctc_tty_netif_rx(struct sk_buff *skb)
191 ctc_tty_info *info = NULL;
193 DBF_TEXT(trace, 5, __FUNCTION__);
196 if ((!skb->dev) || (!driver) || ctc_tty_shuttingdown) {
200 for (i = 0; i < CTC_TTY_MAX_DEVICES; i++)
201 if (driver->info[i].netdev == skb->dev) {
202 info = &driver->info[i];
213 if (memcmp(skb->data, &ctc_tty_magic, sizeof(__u32))) {
217 skb_pull(skb, sizeof(__u32));
219 i = *((int *)skb->data);
220 skb_pull(skb, sizeof(info->mcr));
221 if (i & UART_MCR_RTS) {
222 info->msr |= UART_MSR_CTS;
223 if (info->flags & CTC_ASYNC_CTS_FLOW)
224 info->tty->hw_stopped = 0;
226 info->msr &= ~UART_MSR_CTS;
227 if (info->flags & CTC_ASYNC_CTS_FLOW)
228 info->tty->hw_stopped = 1;
230 if (i & UART_MCR_DTR)
231 info->msr |= UART_MSR_DSR;
233 info->msr &= ~UART_MSR_DSR;
238 /* Try to deliver directly via tty-flip-buf if queue is empty */
239 if (skb_queue_empty(&info->rx_queue))
240 if (ctc_tty_try_read(info, skb))
242 /* Direct deliver failed or queue wasn't empty.
243 * Queue up for later dequeueing via timer-irq.
245 skb_queue_tail(&info->rx_queue, skb);
246 /* Schedule dequeuing */
247 tasklet_schedule(&info->tasklet);
251 ctc_tty_tint(ctc_tty_info * info)
253 struct sk_buff *skb = skb_dequeue(&info->tx_queue);
254 int stopped = (info->tty->hw_stopped || info->tty->stopped);
258 DBF_TEXT(trace, 4, __FUNCTION__);
264 if (info->flags & CTC_ASYNC_TX_LINESTAT) {
265 int skb_res = info->netdev->hard_header_len +
266 sizeof(info->mcr) + sizeof(__u32);
267 /* If we must update line status,
268 * create an empty dummy skb and insert it.
271 skb_queue_head(&info->tx_queue, skb);
273 skb = dev_alloc_skb(skb_res);
276 "ctc_tty: Out of memory in %s%d tint\n",
277 CTC_TTY_NAME, info->line);
280 skb_reserve(skb, skb_res);
287 skb_queue_head(&info->tx_queue, skb);
292 printk(KERN_DEBUG "tint: %d %02x\n", skb->len, *(skb->data));
294 printk(KERN_DEBUG "tint: %d STAT\n", skb->len);
296 memcpy(skb_push(skb, sizeof(info->mcr)), &info->mcr, sizeof(info->mcr));
297 memcpy(skb_push(skb, sizeof(__u32)), &ctc_tty_magic, sizeof(__u32));
298 rc = info->netdev->hard_start_xmit(skb, info->netdev);
300 skb_pull(skb, sizeof(info->mcr) + sizeof(__u32));
302 skb_queue_head(&info->tx_queue, skb);
306 struct tty_struct *tty = info->tty;
308 info->flags &= ~CTC_ASYNC_TX_LINESTAT;
313 return (skb_queue_empty(&info->tx_queue) ? 0 : 1);
316 /************************************************************
320 * mostly "stolen" from original Linux-serial.c and friends.
322 ************************************************************/
325 ctc_tty_paranoia_check(ctc_tty_info * info, char *name, const char *routine)
327 #ifdef MODEM_PARANOIA_CHECK
329 printk(KERN_WARNING "ctc_tty: null info_struct for %s in %s\n",
333 if (info->magic != CTC_ASYNC_MAGIC) {
334 printk(KERN_WARNING "ctc_tty: bad magic for info struct %s in %s\n",
343 ctc_tty_inject(ctc_tty_info *info, char c)
348 DBF_TEXT(trace, 4, __FUNCTION__);
349 if (ctc_tty_shuttingdown)
351 skb_res = info->netdev->hard_header_len + sizeof(info->mcr) +
353 skb = dev_alloc_skb(skb_res);
356 "ctc_tty: Out of memory in %s%d tx_inject\n",
357 CTC_TTY_NAME, info->line);
360 skb_reserve(skb, skb_res);
361 *(skb_put(skb, 1)) = c;
362 skb_queue_head(&info->tx_queue, skb);
363 tasklet_schedule(&info->tasklet);
367 ctc_tty_transmit_status(ctc_tty_info *info)
369 DBF_TEXT(trace, 5, __FUNCTION__);
370 if (ctc_tty_shuttingdown)
372 info->flags |= CTC_ASYNC_TX_LINESTAT;
373 tasklet_schedule(&info->tasklet);
377 ctc_tty_change_speed(ctc_tty_info * info)
383 DBF_TEXT(trace, 3, __FUNCTION__);
384 if (!info->tty || !info->tty->termios)
386 cflag = info->tty->termios->c_cflag;
388 quot = i = cflag & CBAUD;
392 info->tty->termios->c_cflag &= ~CBAUDEX;
397 info->mcr |= UART_MCR_DTR;
398 info->mcr |= UART_MCR_RTS;
399 ctc_tty_transmit_status(info);
401 info->mcr &= ~UART_MCR_DTR;
402 info->mcr &= ~UART_MCR_RTS;
403 ctc_tty_transmit_status(info);
407 /* CTS flow control flag and modem status interrupts */
408 if (cflag & CRTSCTS) {
409 info->flags |= CTC_ASYNC_CTS_FLOW;
411 info->flags &= ~CTC_ASYNC_CTS_FLOW;
413 info->flags &= ~CTC_ASYNC_CHECK_CD;
415 info->flags |= CTC_ASYNC_CHECK_CD;
420 ctc_tty_startup(ctc_tty_info * info)
422 DBF_TEXT(trace, 3, __FUNCTION__);
423 if (info->flags & CTC_ASYNC_INITIALIZED)
425 #ifdef CTC_DEBUG_MODEM_OPEN
426 printk(KERN_DEBUG "starting up %s%d ...\n", CTC_TTY_NAME, info->line);
429 * Now, initialize the UART
431 info->mcr = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
433 clear_bit(TTY_IO_ERROR, &info->tty->flags);
435 * and set the speed of the serial port
437 ctc_tty_change_speed(info);
439 info->flags |= CTC_ASYNC_INITIALIZED;
440 if (!(info->flags & CTC_ASYNC_NETDEV_OPEN))
441 info->netdev->open(info->netdev);
442 info->flags |= CTC_ASYNC_NETDEV_OPEN;
447 ctc_tty_stopdev(unsigned long data)
449 ctc_tty_info *info = (ctc_tty_info *)data;
451 if ((!info) || (!info->netdev) ||
452 (info->flags & CTC_ASYNC_INITIALIZED))
454 info->netdev->stop(info->netdev);
455 info->flags &= ~CTC_ASYNC_NETDEV_OPEN;
459 * This routine will shutdown a serial port; interrupts are disabled, and
460 * DTR is dropped if the hangup on close termio flag is on.
463 ctc_tty_shutdown(ctc_tty_info * info)
465 DBF_TEXT(trace, 3, __FUNCTION__);
466 if (!(info->flags & CTC_ASYNC_INITIALIZED))
468 #ifdef CTC_DEBUG_MODEM_OPEN
469 printk(KERN_DEBUG "Shutting down %s%d ....\n", CTC_TTY_NAME, info->line);
471 info->msr &= ~UART_MSR_RI;
472 if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
473 info->mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
475 set_bit(TTY_IO_ERROR, &info->tty->flags);
476 mod_timer(&info->stoptimer, jiffies + (10 * HZ));
477 skb_queue_purge(&info->tx_queue);
478 skb_queue_purge(&info->rx_queue);
479 info->flags &= ~CTC_ASYNC_INITIALIZED;
482 /* ctc_tty_write() is the main send-routine. It is called from the upper
483 * levels within the kernel to perform sending data. Depending on the
484 * online-flag it either directs output to the at-command-interpreter or
485 * to the lower level. Additional tasks done here:
486 * - If online, check for escape-sequence (+++)
487 * - If sending audio-data, call ctc_tty_DLEdown() to parse DLE-codes.
488 * - If receiving audio-data, call ctc_tty_end_vrx() to abort if needed.
489 * - If dialing, abort dial.
492 ctc_tty_write(struct tty_struct *tty, int from_user, const u_char * buf, int count)
496 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
498 DBF_TEXT(trace, 5, __FUNCTION__);
499 if (ctc_tty_shuttingdown)
501 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_write"))
510 down(&info->write_sem);
515 c = (count < CTC_TTY_XMIT_SIZE) ? count : CTC_TTY_XMIT_SIZE;
519 skb_res = info->netdev->hard_header_len + sizeof(info->mcr) +
521 skb = dev_alloc_skb(skb_res + c);
524 "ctc_tty: Out of memory in %s%d write\n",
525 CTC_TTY_NAME, info->line);
528 skb_reserve(skb, skb_res);
530 copy_from_user(skb_put(skb, c),
531 (const u_char __user *)buf, c);
533 memcpy(skb_put(skb, c), buf, c);
534 skb_queue_tail(&info->tx_queue, skb);
539 if (skb_queue_len(&info->tx_queue)) {
540 info->lsr &= ~UART_LSR_TEMT;
541 tasklet_schedule(&info->tasklet);
544 up(&info->write_sem);
546 DBF_TEXT(trace, 6, __FUNCTION__);
551 ctc_tty_write_room(struct tty_struct *tty)
553 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
555 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_write_room"))
557 return CTC_TTY_XMIT_SIZE;
561 ctc_tty_chars_in_buffer(struct tty_struct *tty)
563 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
565 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_chars_in_buffer"))
571 ctc_tty_flush_buffer(struct tty_struct *tty)
576 DBF_TEXT(trace, 4, __FUNCTION__);
579 spin_lock_irqsave(&ctc_tty_lock, flags);
580 info = (ctc_tty_info *) tty->driver_data;
581 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_flush_buffer")) {
582 spin_unlock_irqrestore(&ctc_tty_lock, flags);
585 skb_queue_purge(&info->tx_queue);
586 info->lsr |= UART_LSR_TEMT;
587 spin_unlock_irqrestore(&ctc_tty_lock, flags);
588 wake_up_interruptible(&tty->write_wait);
591 DBF_TEXT_(trace, 2, "ex: %s ", __FUNCTION__);
596 ctc_tty_flush_chars(struct tty_struct *tty)
598 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
600 DBF_TEXT(trace, 4, __FUNCTION__);
601 if (ctc_tty_shuttingdown)
603 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_flush_chars"))
605 if (tty->stopped || tty->hw_stopped || (!skb_queue_len(&info->tx_queue)))
607 tasklet_schedule(&info->tasklet);
611 * ------------------------------------------------------------
614 * This routine is called by the upper-layer tty layer to signal that
615 * incoming characters should be throttled.
616 * ------------------------------------------------------------
619 ctc_tty_throttle(struct tty_struct *tty)
621 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
623 DBF_TEXT(trace, 4, __FUNCTION__);
624 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_throttle"))
626 info->mcr &= ~UART_MCR_RTS;
628 ctc_tty_inject(info, STOP_CHAR(tty));
629 ctc_tty_transmit_status(info);
633 ctc_tty_unthrottle(struct tty_struct *tty)
635 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
637 DBF_TEXT(trace, 4, __FUNCTION__);
638 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_unthrottle"))
640 info->mcr |= UART_MCR_RTS;
642 ctc_tty_inject(info, START_CHAR(tty));
643 ctc_tty_transmit_status(info);
647 * ------------------------------------------------------------
648 * ctc_tty_ioctl() and friends
649 * ------------------------------------------------------------
653 * ctc_tty_get_lsr_info - get line status register info
655 * Purpose: Let user call ioctl() to get info when the UART physically
656 * is emptied. On bus types like RS485, the transmitter must
657 * release the bus after transmitting. This must be done when
658 * the transmit shift register is empty, not be done when the
659 * transmit holding register is empty. This functionality
660 * allows RS485 driver to be written in user space.
663 ctc_tty_get_lsr_info(ctc_tty_info * info, uint __user *value)
669 DBF_TEXT(trace, 4, __FUNCTION__);
670 spin_lock_irqsave(&ctc_tty_lock, flags);
672 spin_unlock_irqrestore(&ctc_tty_lock, flags);
673 result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
674 put_user(result, value);
679 static int ctc_tty_tiocmget(struct tty_struct *tty, struct file *file)
681 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
687 DBF_TEXT(trace, 4, __FUNCTION__);
688 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_ioctl"))
690 if (tty->flags & (1 << TTY_IO_ERROR))
694 spin_lock_irqsave(&ctc_tty_lock, flags);
696 spin_unlock_irqrestore(&ctc_tty_lock, flags);
697 result = ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
698 | ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
699 | ((status & UART_MSR_DCD) ? TIOCM_CAR : 0)
700 | ((status & UART_MSR_RI) ? TIOCM_RNG : 0)
701 | ((status & UART_MSR_DSR) ? TIOCM_DSR : 0)
702 | ((status & UART_MSR_CTS) ? TIOCM_CTS : 0);
707 ctc_tty_tiocmset(struct tty_struct *tty, struct file *file,
708 unsigned int set, unsigned int clear)
710 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
712 DBF_TEXT(trace, 4, __FUNCTION__);
713 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_ioctl"))
715 if (tty->flags & (1 << TTY_IO_ERROR))
719 info->mcr |= UART_MCR_RTS;
721 info->mcr |= UART_MCR_DTR;
723 if (clear & TIOCM_RTS)
724 info->mcr &= ~UART_MCR_RTS;
725 if (clear & TIOCM_DTR)
726 info->mcr &= ~UART_MCR_DTR;
728 if ((set | clear) & (TIOCM_RTS|TIOCM_DTR))
729 ctc_tty_transmit_status(info);
734 ctc_tty_ioctl(struct tty_struct *tty, struct file *file,
737 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
741 DBF_TEXT(trace, 4, __FUNCTION__);
742 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_ioctl"))
744 if (tty->flags & (1 << TTY_IO_ERROR))
747 case TCSBRK: /* SVID version: non-zero arg --> no break */
748 #ifdef CTC_DEBUG_MODEM_IOCTL
749 printk(KERN_DEBUG "%s%d ioctl TCSBRK\n", CTC_TTY_NAME, info->line);
751 retval = tty_check_change(tty);
754 tty_wait_until_sent(tty, 0);
756 case TCSBRKP: /* support for POSIX tcsendbreak() */
757 #ifdef CTC_DEBUG_MODEM_IOCTL
758 printk(KERN_DEBUG "%s%d ioctl TCSBRKP\n", CTC_TTY_NAME, info->line);
760 retval = tty_check_change(tty);
763 tty_wait_until_sent(tty, 0);
766 #ifdef CTC_DEBUG_MODEM_IOCTL
767 printk(KERN_DEBUG "%s%d ioctl TIOCGSOFTCAR\n", CTC_TTY_NAME,
770 error = put_user(C_CLOCAL(tty) ? 1 : 0, (ulong __user *) arg);
773 #ifdef CTC_DEBUG_MODEM_IOCTL
774 printk(KERN_DEBUG "%s%d ioctl TIOCSSOFTCAR\n", CTC_TTY_NAME,
777 error = get_user(arg, (ulong __user *) arg);
780 tty->termios->c_cflag =
781 ((tty->termios->c_cflag & ~CLOCAL) |
784 case TIOCSERGETLSR: /* Get line status register */
785 #ifdef CTC_DEBUG_MODEM_IOCTL
786 printk(KERN_DEBUG "%s%d ioctl TIOCSERGETLSR\n", CTC_TTY_NAME,
789 error = verify_area(VERIFY_WRITE, (void __user *) arg, sizeof(uint));
793 return ctc_tty_get_lsr_info(info, (uint __user *) arg);
795 #ifdef CTC_DEBUG_MODEM_IOCTL
796 printk(KERN_DEBUG "UNKNOWN ioctl 0x%08x on %s%d\n", cmd,
797 CTC_TTY_NAME, info->line);
805 ctc_tty_set_termios(struct tty_struct *tty, struct termios *old_termios)
807 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
808 unsigned int cflag = tty->termios->c_cflag;
810 DBF_TEXT(trace, 4, __FUNCTION__);
811 ctc_tty_change_speed(info);
813 /* Handle transition to B0 */
814 if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) {
815 info->mcr &= ~(UART_MCR_DTR|UART_MCR_RTS);
816 ctc_tty_transmit_status(info);
819 /* Handle transition from B0 to other */
820 if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
821 info->mcr |= UART_MCR_DTR;
822 if (!(tty->termios->c_cflag & CRTSCTS) ||
823 !test_bit(TTY_THROTTLED, &tty->flags)) {
824 info->mcr |= UART_MCR_RTS;
826 ctc_tty_transmit_status(info);
829 /* Handle turning off CRTSCTS */
830 if ((old_termios->c_cflag & CRTSCTS) &&
831 !(tty->termios->c_cflag & CRTSCTS))
836 * ------------------------------------------------------------
837 * ctc_tty_open() and friends
838 * ------------------------------------------------------------
841 ctc_tty_block_til_ready(struct tty_struct *tty, struct file *filp, ctc_tty_info *info)
843 DECLARE_WAITQUEUE(wait, NULL);
848 DBF_TEXT(trace, 4, __FUNCTION__);
850 * If the device is in the middle of being closed, then block
851 * until it's done, and then try again.
853 if (tty_hung_up_p(filp) ||
854 (info->flags & CTC_ASYNC_CLOSING)) {
855 if (info->flags & CTC_ASYNC_CLOSING)
856 wait_event(info->close_wait,
857 !(info->flags & CTC_ASYNC_CLOSING));
858 #ifdef MODEM_DO_RESTART
859 if (info->flags & CTC_ASYNC_HUP_NOTIFY)
868 * If non-blocking mode is set, then make the check up front
871 if ((filp->f_flags & O_NONBLOCK) ||
872 (tty->flags & (1 << TTY_IO_ERROR))) {
873 info->flags |= CTC_ASYNC_NORMAL_ACTIVE;
876 if (tty->termios->c_cflag & CLOCAL)
879 * Block waiting for the carrier detect and the line to become
880 * free (i.e., not in use by the callout). While we are in
881 * this loop, info->count is dropped by one, so that
882 * ctc_tty_close() knows when to free things. We restore it upon
883 * exit, either normal or abnormal.
886 add_wait_queue(&info->open_wait, &wait);
887 #ifdef CTC_DEBUG_MODEM_OPEN
888 printk(KERN_DEBUG "ctc_tty_block_til_ready before block: %s%d, count = %d\n",
889 CTC_TTY_NAME, info->line, info->count);
891 spin_lock_irqsave(&ctc_tty_lock, flags);
892 if (!(tty_hung_up_p(filp)))
894 spin_unlock_irqrestore(&ctc_tty_lock, flags);
895 info->blocked_open++;
897 set_current_state(TASK_INTERRUPTIBLE);
898 if (tty_hung_up_p(filp) ||
899 !(info->flags & CTC_ASYNC_INITIALIZED)) {
900 #ifdef MODEM_DO_RESTART
901 if (info->flags & CTC_ASYNC_HUP_NOTIFY)
904 retval = -ERESTARTSYS;
910 if (!(info->flags & CTC_ASYNC_CLOSING) &&
911 (do_clocal || (info->msr & UART_MSR_DCD))) {
914 if (signal_pending(current)) {
915 retval = -ERESTARTSYS;
918 #ifdef CTC_DEBUG_MODEM_OPEN
919 printk(KERN_DEBUG "ctc_tty_block_til_ready blocking: %s%d, count = %d\n",
920 CTC_TTY_NAME, info->line, info->count);
924 current->state = TASK_RUNNING;
925 remove_wait_queue(&info->open_wait, &wait);
926 if (!tty_hung_up_p(filp))
928 info->blocked_open--;
929 #ifdef CTC_DEBUG_MODEM_OPEN
930 printk(KERN_DEBUG "ctc_tty_block_til_ready after blocking: %s%d, count = %d\n",
931 CTC_TTY_NAME, info->line, info->count);
935 info->flags |= CTC_ASYNC_NORMAL_ACTIVE;
940 * This routine is called whenever a serial port is opened. It
941 * enables interrupts for a serial port, linking in its async structure into
942 * the IRQ chain. It also performs the serial-specific
943 * initialization for the tty structure.
946 ctc_tty_open(struct tty_struct *tty, struct file *filp)
949 unsigned long saveflags;
953 DBF_TEXT(trace, 3, __FUNCTION__);
955 if (line < 0 || line > CTC_TTY_MAX_DEVICES)
957 info = &driver->info[line];
958 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_open"))
962 #ifdef CTC_DEBUG_MODEM_OPEN
963 printk(KERN_DEBUG "ctc_tty_open %s, count = %d\n", tty->name,
966 spin_lock_irqsave(&ctc_tty_lock, saveflags);
968 tty->driver_data = info;
970 spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
972 * Start up serial port
974 retval = ctc_tty_startup(info);
976 #ifdef CTC_DEBUG_MODEM_OPEN
977 printk(KERN_DEBUG "ctc_tty_open return after startup\n");
981 retval = ctc_tty_block_til_ready(tty, filp, info);
983 #ifdef CTC_DEBUG_MODEM_OPEN
984 printk(KERN_DEBUG "ctc_tty_open return after ctc_tty_block_til_ready \n");
988 #ifdef CTC_DEBUG_MODEM_OPEN
989 printk(KERN_DEBUG "ctc_tty_open %s successful...\n", tty->name);
995 ctc_tty_close(struct tty_struct *tty, struct file *filp)
997 ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
1000 DBF_TEXT(trace, 3, __FUNCTION__);
1001 if (!info || ctc_tty_paranoia_check(info, tty->name, "ctc_tty_close"))
1003 spin_lock_irqsave(&ctc_tty_lock, flags);
1004 if (tty_hung_up_p(filp)) {
1005 spin_unlock_irqrestore(&ctc_tty_lock, flags);
1006 #ifdef CTC_DEBUG_MODEM_OPEN
1007 printk(KERN_DEBUG "ctc_tty_close return after tty_hung_up_p\n");
1011 if ((tty->count == 1) && (info->count != 1)) {
1013 * Uh, oh. tty->count is 1, which means that the tty
1014 * structure will be freed. Info->count should always
1015 * be one in these conditions. If it's greater than
1016 * one, we've got real problems, since it means the
1017 * serial port won't be shutdown.
1019 printk(KERN_ERR "ctc_tty_close: bad port count; tty->count is 1, "
1020 "info->count is %d\n", info->count);
1023 if (--info->count < 0) {
1024 printk(KERN_ERR "ctc_tty_close: bad port count for %s%d: %d\n",
1025 CTC_TTY_NAME, info->line, info->count);
1029 local_irq_restore(flags);
1030 #ifdef CTC_DEBUG_MODEM_OPEN
1031 printk(KERN_DEBUG "ctc_tty_close after info->count != 0\n");
1035 info->flags |= CTC_ASYNC_CLOSING;
1038 * At this point we stop accepting input. To do this, we
1039 * disable the receive line status interrupts, and tell the
1040 * interrupt driver to stop checking the data ready bit in the
1041 * line status register.
1043 if (info->flags & CTC_ASYNC_INITIALIZED) {
1044 tty_wait_until_sent(tty, 30*HZ); /* 30 seconds timeout */
1046 * Before we drop DTR, make sure the UART transmitter
1047 * has completely drained; this is especially
1048 * important if there is a transmit FIFO!
1050 timeout = jiffies + HZ;
1051 while (!(info->lsr & UART_LSR_TEMT)) {
1052 spin_unlock_irqrestore(&ctc_tty_lock, flags);
1054 spin_lock_irqsave(&ctc_tty_lock, flags);
1055 if (time_after(jiffies,timeout))
1059 ctc_tty_shutdown(info);
1060 if (tty->driver->flush_buffer) {
1061 skb_queue_purge(&info->tx_queue);
1062 info->lsr |= UART_LSR_TEMT;
1064 tty_ldisc_flush(tty);
1067 if (info->blocked_open) {
1068 set_current_state(TASK_INTERRUPTIBLE);
1069 schedule_timeout(HZ/2);
1070 wake_up_interruptible(&info->open_wait);
1072 info->flags &= ~(CTC_ASYNC_NORMAL_ACTIVE | CTC_ASYNC_CLOSING);
1073 wake_up_interruptible(&info->close_wait);
1074 spin_unlock_irqrestore(&ctc_tty_lock, flags);
1075 #ifdef CTC_DEBUG_MODEM_OPEN
1076 printk(KERN_DEBUG "ctc_tty_close normal exit\n");
1081 * ctc_tty_hangup() --- called by tty_hangup() when a hangup is signaled.
1084 ctc_tty_hangup(struct tty_struct *tty)
1086 ctc_tty_info *info = (ctc_tty_info *)tty->driver_data;
1087 unsigned long saveflags;
1088 DBF_TEXT(trace, 3, __FUNCTION__);
1089 if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_hangup"))
1091 ctc_tty_shutdown(info);
1093 info->flags &= ~CTC_ASYNC_NORMAL_ACTIVE;
1094 spin_lock_irqsave(&ctc_tty_lock, saveflags);
1096 spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
1097 wake_up_interruptible(&info->open_wait);
1102 * For all online tty's, try sending data to
1106 ctc_tty_task(unsigned long arg)
1108 ctc_tty_info *info = (void *)arg;
1109 unsigned long saveflags;
1112 DBF_TEXT(trace, 3, __FUNCTION__);
1113 spin_lock_irqsave(&ctc_tty_lock, saveflags);
1114 if ((!ctc_tty_shuttingdown) && info) {
1115 again = ctc_tty_tint(info);
1117 info->lsr |= UART_LSR_TEMT;
1118 again |= ctc_tty_readmodem(info);
1120 tasklet_schedule(&info->tasklet);
1123 spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
1126 static struct tty_operations ctc_ops = {
1127 .open = ctc_tty_open,
1128 .close = ctc_tty_close,
1129 .write = ctc_tty_write,
1130 .flush_chars = ctc_tty_flush_chars,
1131 .write_room = ctc_tty_write_room,
1132 .chars_in_buffer = ctc_tty_chars_in_buffer,
1133 .flush_buffer = ctc_tty_flush_buffer,
1134 .ioctl = ctc_tty_ioctl,
1135 .throttle = ctc_tty_throttle,
1136 .unthrottle = ctc_tty_unthrottle,
1137 .set_termios = ctc_tty_set_termios,
1138 .hangup = ctc_tty_hangup,
1139 .tiocmget = ctc_tty_tiocmget,
1140 .tiocmset = ctc_tty_tiocmset,
1148 struct tty_driver *device;
1150 DBF_TEXT(trace, 2, __FUNCTION__);
1151 driver = kmalloc(sizeof(ctc_tty_driver), GFP_KERNEL);
1152 if (driver == NULL) {
1153 printk(KERN_WARNING "Out of memory in ctc_tty_modem_init\n");
1156 memset(driver, 0, sizeof(ctc_tty_driver));
1157 device = alloc_tty_driver(CTC_TTY_MAX_DEVICES);
1160 printk(KERN_WARNING "Out of memory in ctc_tty_modem_init\n");
1164 device->devfs_name = "ctc/" CTC_TTY_NAME;
1165 device->name = CTC_TTY_NAME;
1166 device->major = CTC_TTY_MAJOR;
1167 device->minor_start = 0;
1168 device->type = TTY_DRIVER_TYPE_SERIAL;
1169 device->subtype = SERIAL_TYPE_NORMAL;
1170 device->init_termios = tty_std_termios;
1171 device->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1172 device->flags = TTY_DRIVER_REAL_RAW;
1173 device->driver_name = "ctc_tty",
1174 tty_set_operations(device, &ctc_ops);
1175 if (tty_register_driver(device)) {
1176 printk(KERN_WARNING "ctc_tty: Couldn't register serial-device\n");
1177 put_tty_driver(device);
1181 driver->ctc_tty_device = device;
1182 for (i = 0; i < CTC_TTY_MAX_DEVICES; i++) {
1183 info = &driver->info[i];
1184 init_MUTEX(&info->write_sem);
1185 tasklet_init(&info->tasklet, ctc_tty_task,
1186 (unsigned long) info);
1187 info->magic = CTC_ASYNC_MAGIC;
1191 info->blocked_open = 0;
1192 init_waitqueue_head(&info->open_wait);
1193 init_waitqueue_head(&info->close_wait);
1194 skb_queue_head_init(&info->tx_queue);
1195 skb_queue_head_init(&info->rx_queue);
1196 init_timer(&info->stoptimer);
1197 info->stoptimer.function = ctc_tty_stopdev;
1198 info->stoptimer.data = (unsigned long)info;
1199 info->mcr = UART_MCR_RTS;
1205 ctc_tty_register_netdev(struct net_device *dev) {
1210 DBF_TEXT(trace, 2, __FUNCTION__);
1211 if ((!dev) || (!dev->name)) {
1213 "ctc_tty_register_netdev called "
1214 "with NULL dev or NULL dev-name\n");
1219 * If the name is a format string the caller wants us to
1220 * do a name allocation : format string must end with %d
1222 if (strchr(dev->name, '%'))
1224 int err = dev_alloc_name(dev, dev->name); // dev->name is changed by this
1226 printk(KERN_DEBUG "dev_alloc returned error %d\n", err);
1232 for (p = dev->name; p && ((*p < '0') || (*p > '9')); p++);
1233 ttynum = simple_strtoul(p, &err, 0);
1234 if ((ttynum < 0) || (ttynum >= CTC_TTY_MAX_DEVICES) ||
1237 "ctc_tty_register_netdev called "
1238 "with number in name '%s'\n", dev->name);
1241 if (driver->info[ttynum].netdev) {
1243 "ctc_tty_register_netdev called "
1244 "for already registered device '%s'\n",
1248 driver->info[ttynum].netdev = dev;
1253 ctc_tty_unregister_netdev(struct net_device *dev) {
1255 unsigned long saveflags;
1256 ctc_tty_info *info = NULL;
1258 DBF_TEXT(trace, 2, __FUNCTION__);
1259 spin_lock_irqsave(&ctc_tty_lock, saveflags);
1260 for (i = 0; i < CTC_TTY_MAX_DEVICES; i++)
1261 if (driver->info[i].netdev == dev) {
1262 info = &driver->info[i];
1266 info->netdev = NULL;
1267 skb_queue_purge(&info->tx_queue);
1268 skb_queue_purge(&info->rx_queue);
1270 spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
1274 ctc_tty_cleanup(void) {
1275 unsigned long saveflags;
1277 DBF_TEXT(trace, 2, __FUNCTION__);
1278 spin_lock_irqsave(&ctc_tty_lock, saveflags);
1279 ctc_tty_shuttingdown = 1;
1280 spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
1281 tty_unregister_driver(driver->ctc_tty_device);
1282 put_tty_driver(driver->ctc_tty_device);