diff options
Diffstat (limited to 'drivers/s390/net/ctctty.c')
| -rw-r--r-- | drivers/s390/net/ctctty.c | 1276 |
1 files changed, 1276 insertions, 0 deletions
diff --git a/drivers/s390/net/ctctty.c b/drivers/s390/net/ctctty.c new file mode 100644 index 00000000000..9257d60c783 --- /dev/null +++ b/drivers/s390/net/ctctty.c @@ -0,0 +1,1276 @@ +/* + * $Id: ctctty.c,v 1.26 2004/08/04 11:06:55 mschwide Exp $ + * + * CTC / ESCON network driver, tty interface. + * + * Copyright (C) 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Author(s): Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +#include <linux/config.h> +#include <linux/module.h> +#include <linux/tty.h> +#include <linux/serial_reg.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <asm/uaccess.h> +#include <linux/devfs_fs_kernel.h> +#include "ctctty.h" +#include "ctcdbug.h" + +#define CTC_TTY_MAJOR 43 +#define CTC_TTY_MAX_DEVICES 64 + +#define CTC_ASYNC_MAGIC 0x49344C01 /* for paranoia-checking */ +#define CTC_ASYNC_INITIALIZED 0x80000000 /* port was initialized */ +#define CTC_ASYNC_NORMAL_ACTIVE 0x20000000 /* Normal device active */ +#define CTC_ASYNC_CLOSING 0x08000000 /* Serial port is closing */ +#define CTC_ASYNC_CTS_FLOW 0x04000000 /* Do CTS flow control */ +#define CTC_ASYNC_CHECK_CD 0x02000000 /* i.e., CLOCAL */ +#define CTC_ASYNC_HUP_NOTIFY 0x0001 /* Notify tty on hangups/closes */ +#define CTC_ASYNC_NETDEV_OPEN 0x0002 /* Underlying netdev is open */ +#define CTC_ASYNC_TX_LINESTAT 0x0004 /* Must send line status */ +#define CTC_ASYNC_SPLIT_TERMIOS 0x0008 /* Sep. termios for dialin/out */ +#define CTC_TTY_XMIT_SIZE 1024 /* Default bufsize for write */ +#define CTC_SERIAL_XMIT_MAX 4000 /* Maximum bufsize for write */ + +/* Private data (similar to async_struct in <linux/serial.h>) */ +typedef struct { + int magic; + int flags; /* defined in tty.h */ + int mcr; /* Modem control register */ + int msr; /* Modem status register */ + int lsr; /* Line status register */ + int line; + int count; /* # of fd on device */ + int blocked_open; /* # of blocked opens */ + struct net_device *netdev; + struct sk_buff_head tx_queue; /* transmit queue */ + struct sk_buff_head rx_queue; /* receive queue */ + struct tty_struct *tty; /* Pointer to corresponding tty */ + wait_queue_head_t open_wait; + wait_queue_head_t close_wait; + struct semaphore write_sem; + struct tasklet_struct tasklet; + struct timer_list stoptimer; +} ctc_tty_info; + +/* Description of one CTC-tty */ +typedef struct { + struct tty_driver *ctc_tty_device; /* tty-device */ + ctc_tty_info info[CTC_TTY_MAX_DEVICES]; /* Private data */ +} ctc_tty_driver; + +static ctc_tty_driver *driver; + +/* Leave this unchanged unless you know what you do! */ +#define MODEM_PARANOIA_CHECK +#define MODEM_DO_RESTART + +#define CTC_TTY_NAME "ctctty" + +static __u32 ctc_tty_magic = CTC_ASYNC_MAGIC; +static int ctc_tty_shuttingdown = 0; + +static spinlock_t ctc_tty_lock; + +/* ctc_tty_try_read() is called from within ctc_tty_rcv_skb() + * to stuff incoming data directly into a tty's flip-buffer. If the + * flip buffer is full, the packet gets queued up. + * + * Return: + * 1 = Success + * 0 = Failure, data has to be buffered and later processed by + * ctc_tty_readmodem(). + */ +static int +ctc_tty_try_read(ctc_tty_info * info, struct sk_buff *skb) +{ + int c; + int len; + struct tty_struct *tty; + + DBF_TEXT(trace, 5, __FUNCTION__); + if ((tty = info->tty)) { + if (info->mcr & UART_MCR_RTS) { + c = TTY_FLIPBUF_SIZE - tty->flip.count; + len = skb->len; + if (c >= len) { + memcpy(tty->flip.char_buf_ptr, skb->data, len); + memset(tty->flip.flag_buf_ptr, 0, len); + tty->flip.count += len; + tty->flip.char_buf_ptr += len; + tty->flip.flag_buf_ptr += len; + tty_flip_buffer_push(tty); + kfree_skb(skb); + return 1; + } + } + } + return 0; +} + +/* ctc_tty_readmodem() is called periodically from within timer-interrupt. + * It tries getting received data from the receive queue an stuff it into + * the tty's flip-buffer. + */ +static int +ctc_tty_readmodem(ctc_tty_info *info) +{ + int ret = 1; + struct tty_struct *tty; + + DBF_TEXT(trace, 5, __FUNCTION__); + if ((tty = info->tty)) { + if (info->mcr & UART_MCR_RTS) { + int c = TTY_FLIPBUF_SIZE - tty->flip.count; + struct sk_buff *skb; + + if ((c > 0) && (skb = skb_dequeue(&info->rx_queue))) { + int len = skb->len; + if (len > c) + len = c; + memcpy(tty->flip.char_buf_ptr, skb->data, len); + skb_pull(skb, len); + memset(tty->flip.flag_buf_ptr, 0, len); + tty->flip.count += len; + tty->flip.char_buf_ptr += len; + tty->flip.flag_buf_ptr += len; + tty_flip_buffer_push(tty); + if (skb->len > 0) + skb_queue_head(&info->rx_queue, skb); + else { + kfree_skb(skb); + ret = skb_queue_len(&info->rx_queue); + } + } + } + } + return ret; +} + +void +ctc_tty_setcarrier(struct net_device *netdev, int on) +{ + int i; + + DBF_TEXT(trace, 4, __FUNCTION__); + if ((!driver) || ctc_tty_shuttingdown) + return; + for (i = 0; i < CTC_TTY_MAX_DEVICES; i++) + if (driver->info[i].netdev == netdev) { + ctc_tty_info *info = &driver->info[i]; + if (on) + info->msr |= UART_MSR_DCD; + else + info->msr &= ~UART_MSR_DCD; + if ((info->flags & CTC_ASYNC_CHECK_CD) && (!on)) + tty_hangup(info->tty); + } +} + +void +ctc_tty_netif_rx(struct sk_buff *skb) +{ + int i; + ctc_tty_info *info = NULL; + + DBF_TEXT(trace, 5, __FUNCTION__); + if (!skb) + return; + if ((!skb->dev) || (!driver) || ctc_tty_shuttingdown) { + dev_kfree_skb(skb); + return; + } + for (i = 0; i < CTC_TTY_MAX_DEVICES; i++) + if (driver->info[i].netdev == skb->dev) { + info = &driver->info[i]; + break; + } + if (!info) { + dev_kfree_skb(skb); + return; + } + if (skb->len < 6) { + dev_kfree_skb(skb); + return; + } + if (memcmp(skb->data, &ctc_tty_magic, sizeof(__u32))) { + dev_kfree_skb(skb); + return; + } + skb_pull(skb, sizeof(__u32)); + + i = *((int *)skb->data); + skb_pull(skb, sizeof(info->mcr)); + if (i & UART_MCR_RTS) { + info->msr |= UART_MSR_CTS; + if (info->flags & CTC_ASYNC_CTS_FLOW) + info->tty->hw_stopped = 0; + } else { + info->msr &= ~UART_MSR_CTS; + if (info->flags & CTC_ASYNC_CTS_FLOW) + info->tty->hw_stopped = 1; + } + if (i & UART_MCR_DTR) + info->msr |= UART_MSR_DSR; + else + info->msr &= ~UART_MSR_DSR; + if (skb->len <= 0) { + kfree_skb(skb); + return; + } + /* Try to deliver directly via tty-flip-buf if queue is empty */ + if (skb_queue_empty(&info->rx_queue)) + if (ctc_tty_try_read(info, skb)) + return; + /* Direct deliver failed or queue wasn't empty. + * Queue up for later dequeueing via timer-irq. + */ + skb_queue_tail(&info->rx_queue, skb); + /* Schedule dequeuing */ + tasklet_schedule(&info->tasklet); +} + +static int +ctc_tty_tint(ctc_tty_info * info) +{ + struct sk_buff *skb = skb_dequeue(&info->tx_queue); + int stopped = (info->tty->hw_stopped || info->tty->stopped); + int wake = 1; + int rc; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (!info->netdev) { + if (skb) + kfree_skb(skb); + return 0; + } + if (info->flags & CTC_ASYNC_TX_LINESTAT) { + int skb_res = info->netdev->hard_header_len + + sizeof(info->mcr) + sizeof(__u32); + /* If we must update line status, + * create an empty dummy skb and insert it. + */ + if (skb) + skb_queue_head(&info->tx_queue, skb); + + skb = dev_alloc_skb(skb_res); + if (!skb) { + printk(KERN_WARNING + "ctc_tty: Out of memory in %s%d tint\n", + CTC_TTY_NAME, info->line); + return 1; + } + skb_reserve(skb, skb_res); + stopped = 0; + wake = 0; + } + if (!skb) + return 0; + if (stopped) { + skb_queue_head(&info->tx_queue, skb); + return 1; + } +#if 0 + if (skb->len > 0) + printk(KERN_DEBUG "tint: %d %02x\n", skb->len, *(skb->data)); + else + printk(KERN_DEBUG "tint: %d STAT\n", skb->len); +#endif + memcpy(skb_push(skb, sizeof(info->mcr)), &info->mcr, sizeof(info->mcr)); + memcpy(skb_push(skb, sizeof(__u32)), &ctc_tty_magic, sizeof(__u32)); + rc = info->netdev->hard_start_xmit(skb, info->netdev); + if (rc) { + skb_pull(skb, sizeof(info->mcr) + sizeof(__u32)); + if (skb->len > 0) + skb_queue_head(&info->tx_queue, skb); + else + kfree_skb(skb); + } else { + struct tty_struct *tty = info->tty; + + info->flags &= ~CTC_ASYNC_TX_LINESTAT; + if (tty) { + tty_wakeup(tty); + } + } + return (skb_queue_empty(&info->tx_queue) ? 0 : 1); +} + +/************************************************************ + * + * Modem-functions + * + * mostly "stolen" from original Linux-serial.c and friends. + * + ************************************************************/ + +static inline int +ctc_tty_paranoia_check(ctc_tty_info * info, char *name, const char *routine) +{ +#ifdef MODEM_PARANOIA_CHECK + if (!info) { + printk(KERN_WARNING "ctc_tty: null info_struct for %s in %s\n", + name, routine); + return 1; + } + if (info->magic != CTC_ASYNC_MAGIC) { + printk(KERN_WARNING "ctc_tty: bad magic for info struct %s in %s\n", + name, routine); + return 1; + } +#endif + return 0; +} + +static void +ctc_tty_inject(ctc_tty_info *info, char c) +{ + int skb_res; + struct sk_buff *skb; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_shuttingdown) + return; + skb_res = info->netdev->hard_header_len + sizeof(info->mcr) + + sizeof(__u32) + 1; + skb = dev_alloc_skb(skb_res); + if (!skb) { + printk(KERN_WARNING + "ctc_tty: Out of memory in %s%d tx_inject\n", + CTC_TTY_NAME, info->line); + return; + } + skb_reserve(skb, skb_res); + *(skb_put(skb, 1)) = c; + skb_queue_head(&info->tx_queue, skb); + tasklet_schedule(&info->tasklet); +} + +static void +ctc_tty_transmit_status(ctc_tty_info *info) +{ + DBF_TEXT(trace, 5, __FUNCTION__); + if (ctc_tty_shuttingdown) + return; + info->flags |= CTC_ASYNC_TX_LINESTAT; + tasklet_schedule(&info->tasklet); +} + +static void +ctc_tty_change_speed(ctc_tty_info * info) +{ + unsigned int cflag; + unsigned int quot; + int i; + + DBF_TEXT(trace, 3, __FUNCTION__); + if (!info->tty || !info->tty->termios) + return; + cflag = info->tty->termios->c_cflag; + + quot = i = cflag & CBAUD; + if (i & CBAUDEX) { + i &= ~CBAUDEX; + if (i < 1 || i > 2) + info->tty->termios->c_cflag &= ~CBAUDEX; + else + i += 15; + } + if (quot) { + info->mcr |= UART_MCR_DTR; + info->mcr |= UART_MCR_RTS; + ctc_tty_transmit_status(info); + } else { + info->mcr &= ~UART_MCR_DTR; + info->mcr &= ~UART_MCR_RTS; + ctc_tty_transmit_status(info); + return; + } + + /* CTS flow control flag and modem status interrupts */ + if (cflag & CRTSCTS) { + info->flags |= CTC_ASYNC_CTS_FLOW; + } else + info->flags &= ~CTC_ASYNC_CTS_FLOW; + if (cflag & CLOCAL) + info->flags &= ~CTC_ASYNC_CHECK_CD; + else { + info->flags |= CTC_ASYNC_CHECK_CD; + } +} + +static int +ctc_tty_startup(ctc_tty_info * info) +{ + DBF_TEXT(trace, 3, __FUNCTION__); + if (info->flags & CTC_ASYNC_INITIALIZED) + return 0; +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "starting up %s%d ...\n", CTC_TTY_NAME, info->line); +#endif + /* + * Now, initialize the UART + */ + info->mcr = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2; + if (info->tty) + clear_bit(TTY_IO_ERROR, &info->tty->flags); + /* + * and set the speed of the serial port + */ + ctc_tty_change_speed(info); + + info->flags |= CTC_ASYNC_INITIALIZED; + if (!(info->flags & CTC_ASYNC_NETDEV_OPEN)) + info->netdev->open(info->netdev); + info->flags |= CTC_ASYNC_NETDEV_OPEN; + return 0; +} + +static void +ctc_tty_stopdev(unsigned long data) +{ + ctc_tty_info *info = (ctc_tty_info *)data; + + if ((!info) || (!info->netdev) || + (info->flags & CTC_ASYNC_INITIALIZED)) + return; + info->netdev->stop(info->netdev); + info->flags &= ~CTC_ASYNC_NETDEV_OPEN; +} + +/* + * This routine will shutdown a serial port; interrupts are disabled, and + * DTR is dropped if the hangup on close termio flag is on. + */ +static void +ctc_tty_shutdown(ctc_tty_info * info) +{ + DBF_TEXT(trace, 3, __FUNCTION__); + if (!(info->flags & CTC_ASYNC_INITIALIZED)) + return; +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "Shutting down %s%d ....\n", CTC_TTY_NAME, info->line); +#endif + info->msr &= ~UART_MSR_RI; + if (!info->tty || (info->tty->termios->c_cflag & HUPCL)) + info->mcr &= ~(UART_MCR_DTR | UART_MCR_RTS); + if (info->tty) + set_bit(TTY_IO_ERROR, &info->tty->flags); + mod_timer(&info->stoptimer, jiffies + (10 * HZ)); + skb_queue_purge(&info->tx_queue); + skb_queue_purge(&info->rx_queue); + info->flags &= ~CTC_ASYNC_INITIALIZED; +} + +/* ctc_tty_write() is the main send-routine. It is called from the upper + * levels within the kernel to perform sending data. Depending on the + * online-flag it either directs output to the at-command-interpreter or + * to the lower level. Additional tasks done here: + * - If online, check for escape-sequence (+++) + * - If sending audio-data, call ctc_tty_DLEdown() to parse DLE-codes. + * - If receiving audio-data, call ctc_tty_end_vrx() to abort if needed. + * - If dialing, abort dial. + */ +static int +ctc_tty_write(struct tty_struct *tty, const u_char * buf, int count) +{ + int c; + int total = 0; + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + DBF_TEXT(trace, 5, __FUNCTION__); + if (ctc_tty_shuttingdown) + goto ex; + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_write")) + goto ex; + if (!tty) + goto ex; + if (!info->netdev) { + total = -ENODEV; + goto ex; + } + while (1) { + struct sk_buff *skb; + int skb_res; + + c = (count < CTC_TTY_XMIT_SIZE) ? count : CTC_TTY_XMIT_SIZE; + if (c <= 0) + break; + + skb_res = info->netdev->hard_header_len + sizeof(info->mcr) + + + sizeof(__u32); + skb = dev_alloc_skb(skb_res + c); + if (!skb) { + printk(KERN_WARNING + "ctc_tty: Out of memory in %s%d write\n", + CTC_TTY_NAME, info->line); + break; + } + skb_reserve(skb, skb_res); + memcpy(skb_put(skb, c), buf, c); + skb_queue_tail(&info->tx_queue, skb); + buf += c; + total += c; + count -= c; + } + if (skb_queue_len(&info->tx_queue)) { + info->lsr &= ~UART_LSR_TEMT; + tasklet_schedule(&info->tasklet); + } +ex: + DBF_TEXT(trace, 6, __FUNCTION__); + return total; +} + +static int +ctc_tty_write_room(struct tty_struct *tty) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_write_room")) + return 0; + return CTC_TTY_XMIT_SIZE; +} + +static int +ctc_tty_chars_in_buffer(struct tty_struct *tty) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_chars_in_buffer")) + return 0; + return 0; +} + +static void +ctc_tty_flush_buffer(struct tty_struct *tty) +{ + ctc_tty_info *info; + unsigned long flags; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (!tty) + goto ex; + spin_lock_irqsave(&ctc_tty_lock, flags); + info = (ctc_tty_info *) tty->driver_data; + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_flush_buffer")) { + spin_unlock_irqrestore(&ctc_tty_lock, flags); + goto ex; + } + skb_queue_purge(&info->tx_queue); + info->lsr |= UART_LSR_TEMT; + spin_unlock_irqrestore(&ctc_tty_lock, flags); + wake_up_interruptible(&tty->write_wait); + tty_wakeup(tty); +ex: + DBF_TEXT_(trace, 2, "ex: %s ", __FUNCTION__); + return; +} + +static void +ctc_tty_flush_chars(struct tty_struct *tty) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_shuttingdown) + return; + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_flush_chars")) + return; + if (tty->stopped || tty->hw_stopped || (!skb_queue_len(&info->tx_queue))) + return; + tasklet_schedule(&info->tasklet); +} + +/* + * ------------------------------------------------------------ + * ctc_tty_throttle() + * + * This routine is called by the upper-layer tty layer to signal that + * incoming characters should be throttled. + * ------------------------------------------------------------ + */ +static void +ctc_tty_throttle(struct tty_struct *tty) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_throttle")) + return; + info->mcr &= ~UART_MCR_RTS; + if (I_IXOFF(tty)) + ctc_tty_inject(info, STOP_CHAR(tty)); + ctc_tty_transmit_status(info); +} + +static void +ctc_tty_unthrottle(struct tty_struct *tty) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_unthrottle")) + return; + info->mcr |= UART_MCR_RTS; + if (I_IXOFF(tty)) + ctc_tty_inject(info, START_CHAR(tty)); + ctc_tty_transmit_status(info); +} + +/* + * ------------------------------------------------------------ + * ctc_tty_ioctl() and friends + * ------------------------------------------------------------ + */ + +/* + * ctc_tty_get_lsr_info - get line status register info + * + * Purpose: Let user call ioctl() to get info when the UART physically + * is emptied. On bus types like RS485, the transmitter must + * release the bus after transmitting. This must be done when + * the transmit shift register is empty, not be done when the + * transmit holding register is empty. This functionality + * allows RS485 driver to be written in user space. + */ +static int +ctc_tty_get_lsr_info(ctc_tty_info * info, uint __user *value) +{ + u_char status; + uint result; + ulong flags; + + DBF_TEXT(trace, 4, __FUNCTION__); + spin_lock_irqsave(&ctc_tty_lock, flags); + status = info->lsr; + spin_unlock_irqrestore(&ctc_tty_lock, flags); + result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0); + put_user(result, value); + return 0; +} + + +static int ctc_tty_tiocmget(struct tty_struct *tty, struct file *file) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + u_char control, + status; + uint result; + ulong flags; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_ioctl")) + return -ENODEV; + if (tty->flags & (1 << TTY_IO_ERROR)) + return -EIO; + + control = info->mcr; + spin_lock_irqsave(&ctc_tty_lock, flags); + status = info->msr; + spin_unlock_irqrestore(&ctc_tty_lock, flags); + result = ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) + | ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) + | ((status & UART_MSR_DCD) ? TIOCM_CAR : 0) + | ((status & UART_MSR_RI) ? TIOCM_RNG : 0) + | ((status & UART_MSR_DSR) ? TIOCM_DSR : 0) + | ((status & UART_MSR_CTS) ? TIOCM_CTS : 0); + return result; +} + +static int +ctc_tty_tiocmset(struct tty_struct *tty, struct file *file, + unsigned int set, unsigned int clear) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_ioctl")) + return -ENODEV; + if (tty->flags & (1 << TTY_IO_ERROR)) + return -EIO; + + if (set & TIOCM_RTS) + info->mcr |= UART_MCR_RTS; + if (set & TIOCM_DTR) + info->mcr |= UART_MCR_DTR; + + if (clear & TIOCM_RTS) + info->mcr &= ~UART_MCR_RTS; + if (clear & TIOCM_DTR) + info->mcr &= ~UART_MCR_DTR; + + if ((set | clear) & (TIOCM_RTS|TIOCM_DTR)) + ctc_tty_transmit_status(info); + return 0; +} + +static int +ctc_tty_ioctl(struct tty_struct *tty, struct file *file, + uint cmd, ulong arg) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + int error; + int retval; + + DBF_TEXT(trace, 4, __FUNCTION__); + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_ioctl")) + return -ENODEV; + if (tty->flags & (1 << TTY_IO_ERROR)) + return -EIO; + switch (cmd) { + case TCSBRK: /* SVID version: non-zero arg --> no break */ +#ifdef CTC_DEBUG_MODEM_IOCTL + printk(KERN_DEBUG "%s%d ioctl TCSBRK\n", CTC_TTY_NAME, info->line); +#endif + retval = tty_check_change(tty); + if (retval) + return retval; + tty_wait_until_sent(tty, 0); + return 0; + case TCSBRKP: /* support for POSIX tcsendbreak() */ +#ifdef CTC_DEBUG_MODEM_IOCTL + printk(KERN_DEBUG "%s%d ioctl TCSBRKP\n", CTC_TTY_NAME, info->line); +#endif + retval = tty_check_change(tty); + if (retval) + return retval; + tty_wait_until_sent(tty, 0); + return 0; + case TIOCGSOFTCAR: +#ifdef CTC_DEBUG_MODEM_IOCTL + printk(KERN_DEBUG "%s%d ioctl TIOCGSOFTCAR\n", CTC_TTY_NAME, + info->line); +#endif + error = put_user(C_CLOCAL(tty) ? 1 : 0, (ulong __user *) arg); + return error; + case TIOCSSOFTCAR: +#ifdef CTC_DEBUG_MODEM_IOCTL + printk(KERN_DEBUG "%s%d ioctl TIOCSSOFTCAR\n", CTC_TTY_NAME, + info->line); +#endif + error = get_user(arg, (ulong __user *) arg); + if (error) + return error; + tty->termios->c_cflag = + ((tty->termios->c_cflag & ~CLOCAL) | + (arg ? CLOCAL : 0)); + return 0; + case TIOCSERGETLSR: /* Get line status register */ +#ifdef CTC_DEBUG_MODEM_IOCTL + printk(KERN_DEBUG "%s%d ioctl TIOCSERGETLSR\n", CTC_TTY_NAME, + info->line); +#endif + if (access_ok(VERIFY_WRITE, (void __user *) arg, sizeof(uint))) + return ctc_tty_get_lsr_info(info, (uint __user *) arg); + else + return -EFAULT; + default: +#ifdef CTC_DEBUG_MODEM_IOCTL + printk(KERN_DEBUG "UNKNOWN ioctl 0x%08x on %s%d\n", cmd, + CTC_TTY_NAME, info->line); +#endif + return -ENOIOCTLCMD; + } + return 0; +} + +static void +ctc_tty_set_termios(struct tty_struct *tty, struct termios *old_termios) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + unsigned int cflag = tty->termios->c_cflag; + + DBF_TEXT(trace, 4, __FUNCTION__); + ctc_tty_change_speed(info); + + /* Handle transition to B0 */ + if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) { + info->mcr &= ~(UART_MCR_DTR|UART_MCR_RTS); + ctc_tty_transmit_status(info); + } + + /* Handle transition from B0 to other */ + if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { + info->mcr |= UART_MCR_DTR; + if (!(tty->termios->c_cflag & CRTSCTS) || + !test_bit(TTY_THROTTLED, &tty->flags)) { + info->mcr |= UART_MCR_RTS; + } + ctc_tty_transmit_status(info); + } + + /* Handle turning off CRTSCTS */ + if ((old_termios->c_cflag & CRTSCTS) && + !(tty->termios->c_cflag & CRTSCTS)) + tty->hw_stopped = 0; +} + +/* + * ------------------------------------------------------------ + * ctc_tty_open() and friends + * ------------------------------------------------------------ + */ +static int +ctc_tty_block_til_ready(struct tty_struct *tty, struct file *filp, ctc_tty_info *info) +{ + DECLARE_WAITQUEUE(wait, NULL); + int do_clocal = 0; + unsigned long flags; + int retval; + + DBF_TEXT(trace, 4, __FUNCTION__); + /* + * If the device is in the middle of being closed, then block + * until it's done, and then try again. + */ + if (tty_hung_up_p(filp) || + (info->flags & CTC_ASYNC_CLOSING)) { + if (info->flags & CTC_ASYNC_CLOSING) + wait_event(info->close_wait, + !(info->flags & CTC_ASYNC_CLOSING)); +#ifdef MODEM_DO_RESTART + if (info->flags & CTC_ASYNC_HUP_NOTIFY) + return -EAGAIN; + else + return -ERESTARTSYS; +#else + return -EAGAIN; +#endif + } + /* + * If non-blocking mode is set, then make the check up front + * and then exit. + */ + if ((filp->f_flags & O_NONBLOCK) || + (tty->flags & (1 << TTY_IO_ERROR))) { + info->flags |= CTC_ASYNC_NORMAL_ACTIVE; + return 0; + } + if (tty->termios->c_cflag & CLOCAL) + do_clocal = 1; + /* + * Block waiting for the carrier detect and the line to become + * free (i.e., not in use by the callout). While we are in + * this loop, info->count is dropped by one, so that + * ctc_tty_close() knows when to free things. We restore it upon + * exit, either normal or abnormal. + */ + retval = 0; + add_wait_queue(&info->open_wait, &wait); +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_block_til_ready before block: %s%d, count = %d\n", + CTC_TTY_NAME, info->line, info->count); +#endif + spin_lock_irqsave(&ctc_tty_lock, flags); + if (!(tty_hung_up_p(filp))) + info->count--; + spin_unlock_irqrestore(&ctc_tty_lock, flags); + info->blocked_open++; + while (1) { + set_current_state(TASK_INTERRUPTIBLE); + if (tty_hung_up_p(filp) || + !(info->flags & CTC_ASYNC_INITIALIZED)) { +#ifdef MODEM_DO_RESTART + if (info->flags & CTC_ASYNC_HUP_NOTIFY) + retval = -EAGAIN; + else + retval = -ERESTARTSYS; +#else + retval = -EAGAIN; +#endif + break; + } + if (!(info->flags & CTC_ASYNC_CLOSING) && + (do_clocal || (info->msr & UART_MSR_DCD))) { + break; + } + if (signal_pending(current)) { + retval = -ERESTARTSYS; + break; + } +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_block_til_ready blocking: %s%d, count = %d\n", + CTC_TTY_NAME, info->line, info->count); +#endif + schedule(); + } + current->state = TASK_RUNNING; + remove_wait_queue(&info->open_wait, &wait); + if (!tty_hung_up_p(filp)) + info->count++; + info->blocked_open--; +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_block_til_ready after blocking: %s%d, count = %d\n", + CTC_TTY_NAME, info->line, info->count); +#endif + if (retval) + return retval; + info->flags |= CTC_ASYNC_NORMAL_ACTIVE; + return 0; +} + +/* + * This routine is called whenever a serial port is opened. It + * enables interrupts for a serial port, linking in its async structure into + * the IRQ chain. It also performs the serial-specific + * initialization for the tty structure. + */ +static int +ctc_tty_open(struct tty_struct *tty, struct file *filp) +{ + ctc_tty_info *info; + unsigned long saveflags; + int retval, + line; + + DBF_TEXT(trace, 3, __FUNCTION__); + line = tty->index; + if (line < 0 || line > CTC_TTY_MAX_DEVICES) + return -ENODEV; + info = &driver->info[line]; + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_open")) + return -ENODEV; + if (!info->netdev) + return -ENODEV; +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_open %s, count = %d\n", tty->name, + info->count); +#endif + spin_lock_irqsave(&ctc_tty_lock, saveflags); + info->count++; + tty->driver_data = info; + info->tty = tty; + spin_unlock_irqrestore(&ctc_tty_lock, saveflags); + /* + * Start up serial port + */ + retval = ctc_tty_startup(info); + if (retval) { +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_open return after startup\n"); +#endif + return retval; + } + retval = ctc_tty_block_til_ready(tty, filp, info); + if (retval) { +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_open return after ctc_tty_block_til_ready \n"); +#endif + return retval; + } +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_open %s successful...\n", tty->name); +#endif + return 0; +} + +static void +ctc_tty_close(struct tty_struct *tty, struct file *filp) +{ + ctc_tty_info *info = (ctc_tty_info *) tty->driver_data; + ulong flags; + ulong timeout; + DBF_TEXT(trace, 3, __FUNCTION__); + if (!info || ctc_tty_paranoia_check(info, tty->name, "ctc_tty_close")) + return; + spin_lock_irqsave(&ctc_tty_lock, flags); + if (tty_hung_up_p(filp)) { + spin_unlock_irqrestore(&ctc_tty_lock, flags); +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_close return after tty_hung_up_p\n"); +#endif + return; + } + if ((tty->count == 1) && (info->count != 1)) { + /* + * Uh, oh. tty->count is 1, which means that the tty + * structure will be freed. Info->count should always + * be one in these conditions. If it's greater than + * one, we've got real problems, since it means the + * serial port won't be shutdown. + */ + printk(KERN_ERR "ctc_tty_close: bad port count; tty->count is 1, " + "info->count is %d\n", info->count); + info->count = 1; + } + if (--info->count < 0) { + printk(KERN_ERR "ctc_tty_close: bad port count for %s%d: %d\n", + CTC_TTY_NAME, info->line, info->count); + info->count = 0; + } + if (info->count) { + local_irq_restore(flags); +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_close after info->count != 0\n"); +#endif + return; + } + info->flags |= CTC_ASYNC_CLOSING; + tty->closing = 1; + /* + * At this point we stop accepting input. To do this, we + * disable the receive line status interrupts, and tell the + * interrupt driver to stop checking the data ready bit in the + * line status register. + */ + if (info->flags & CTC_ASYNC_INITIALIZED) { + tty_wait_until_sent(tty, 30*HZ); /* 30 seconds timeout */ + /* + * Before we drop DTR, make sure the UART transmitter + * has completely drained; this is especially + * important if there is a transmit FIFO! + */ + timeout = jiffies + HZ; + while (!(info->lsr & UART_LSR_TEMT)) { + spin_unlock_irqrestore(&ctc_tty_lock, flags); + msleep(500); + spin_lock_irqsave(&ctc_tty_lock, flags); + if (time_after(jiffies,timeout)) + break; + } + } + ctc_tty_shutdown(info); + if (tty->driver->flush_buffer) { + skb_queue_purge(&info->tx_queue); + info->lsr |= UART_LSR_TEMT; + } + tty_ldisc_flush(tty); + info->tty = 0; + tty->closing = 0; + if (info->blocked_open) { + set_current_state(TASK_INTERRUPTIBLE); + schedule_timeout(HZ/2); + wake_up_interruptible(&info->open_wait); + } + info->flags &= ~(CTC_ASYNC_NORMAL_ACTIVE | CTC_ASYNC_CLOSING); + wake_up_interruptible(&info->close_wait); + spin_unlock_irqrestore(&ctc_tty_lock, flags); +#ifdef CTC_DEBUG_MODEM_OPEN + printk(KERN_DEBUG "ctc_tty_close normal exit\n"); +#endif +} + +/* + * ctc_tty_hangup() --- called by tty_hangup() when a hangup is signaled. + */ +static void +ctc_tty_hangup(struct tty_struct *tty) +{ + ctc_tty_info *info = (ctc_tty_info *)tty->driver_data; + unsigned long saveflags; + DBF_TEXT(trace, 3, __FUNCTION__); + if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_hangup")) + return; + ctc_tty_shutdown(info); + info->count = 0; + info->flags &= ~CTC_ASYNC_NORMAL_ACTIVE; + spin_lock_irqsave(&ctc_tty_lock, saveflags); + info->tty = 0; + spin_unlock_irqrestore(&ctc_tty_lock, saveflags); + wake_up_interruptible(&info->open_wait); +} + + +/* + * For all online tty's, try sending data to + * the lower levels. + */ +static void +ctc_tty_task(unsigned long arg) +{ + ctc_tty_info *info = (void *)arg; + unsigned long saveflags; + int again; + + DBF_TEXT(trace, 3, __FUNCTION__); + spin_lock_irqsave(&ctc_tty_lock, saveflags); + if ((!ctc_tty_shuttingdown) && info) { + again = ctc_tty_tint(info); + if (!again) + info->lsr |= UART_LSR_TEMT; + again |= ctc_tty_readmodem(info); + if (again) { + tasklet_schedule(&info->tasklet); + } + } + spin_unlock_irqrestore(&ctc_tty_lock, saveflags); +} + +static struct tty_operations ctc_ops = { + .open = ctc_tty_open, + .close = ctc_tty_close, + .write = ctc_tty_write, + .flush_chars = ctc_tty_flush_chars, + .write_room = ctc_tty_write_room, + .chars_in_buffer = ctc_tty_chars_in_buffer, + .flush_buffer = ctc_tty_flush_buffer, + .ioctl = ctc_tty_ioctl, + .throttle = ctc_tty_throttle, + .unthrottle = ctc_tty_unthrottle, + .set_termios = ctc_tty_set_termios, + .hangup = ctc_tty_hangup, + .tiocmget = ctc_tty_tiocmget, + .tiocmset = ctc_tty_tiocmset, +}; + +int +ctc_tty_init(void) +{ + int i; + ctc_tty_info *info; + struct tty_driver *device; + + DBF_TEXT(trace, 2, __FUNCTION__); + driver = kmalloc(sizeof(ctc_tty_driver), GFP_KERNEL); + if (driver == NULL) { + printk(KERN_WARNING "Out of memory in ctc_tty_modem_init\n"); + return -ENOMEM; + } + memset(driver, 0, sizeof(ctc_tty_driver)); + device = alloc_tty_driver(CTC_TTY_MAX_DEVICES); + if (!device) { + kfree(driver); + printk(KERN_WARNING "Out of memory in ctc_tty_modem_init\n"); + return -ENOMEM; + } + + device->devfs_name = "ctc/" CTC_TTY_NAME; + device->name = CTC_TTY_NAME; + device->major = CTC_TTY_MAJOR; + device->minor_start = 0; + device->type = TTY_DRIVER_TYPE_SERIAL; + device->subtype = SERIAL_TYPE_NORMAL; + device->init_termios = tty_std_termios; + device->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; + device->flags = TTY_DRIVER_REAL_RAW; + device->driver_name = "ctc_tty", + tty_set_operations(device, &ctc_ops); + if (tty_register_driver(device)) { + printk(KERN_WARNING "ctc_tty: Couldn't register serial-device\n"); + put_tty_driver(device); + kfree(driver); + return -1; + } + driver->ctc_tty_device = device; + for (i = 0; i < CTC_TTY_MAX_DEVICES; i++) { + info = &driver->info[i]; + init_MUTEX(&info->write_sem); + tasklet_init(&info->tasklet, ctc_tty_task, + (unsigned long) info); + info->magic = CTC_ASYNC_MAGIC; + info->line = i; + info->tty = 0; + info->count = 0; + info->blocked_open = 0; + init_waitqueue_head(&info->open_wait); + init_waitqueue_head(&info->close_wait); + skb_queue_head_init(&info->tx_queue); + skb_queue_head_init(&info->rx_queue); + init_timer(&info->stoptimer); + info->stoptimer.function = ctc_tty_stopdev; + info->stoptimer.data = (unsigned long)info; + info->mcr = UART_MCR_RTS; + } + return 0; +} + +int +ctc_tty_register_netdev(struct net_device *dev) { + int ttynum; + char *err; + char *p; + + DBF_TEXT(trace, 2, __FUNCTION__); + if ((!dev) || (!dev->name)) { + printk(KERN_WARNING + "ctc_tty_register_netdev called " + "with NULL dev or NULL dev-name\n"); + return -1; + } + + /* + * If the name is a format string the caller wants us to + * do a name allocation : format string must end with %d + */ + if (strchr(dev->name, '%')) + { + int err = dev_alloc_name(dev, dev->name); // dev->name is changed by this + if (err < 0) { + printk(KERN_DEBUG "dev_alloc returned error %d\n", err); + return err; + } + + } + + for (p = dev->name; p && ((*p < '0') || (*p > '9')); p++); + ttynum = simple_strtoul(p, &err, 0); + if ((ttynum < 0) || (ttynum >= CTC_TTY_MAX_DEVICES) || + (err && *err)) { + printk(KERN_WARNING + "ctc_tty_register_netdev called " + "with number in name '%s'\n", dev->name); + return -1; + } + if (driver->info[ttynum].netdev) { + printk(KERN_WARNING + "ctc_tty_register_netdev called " + "for already registered device '%s'\n", + dev->name); + return -1; + } + driver->info[ttynum].netdev = dev; + return 0; +} + +void +ctc_tty_unregister_netdev(struct net_device *dev) { + int i; + unsigned long saveflags; + ctc_tty_info *info = NULL; + + DBF_TEXT(trace, 2, __FUNCTION__); + spin_lock_irqsave(&ctc_tty_lock, saveflags); + for (i = 0; i < CTC_TTY_MAX_DEVICES; i++) + if (driver->info[i].netdev == dev) { + info = &driver->info[i]; + break; + } + if (info) { + info->netdev = NULL; + skb_queue_purge(&info->tx_queue); + skb_queue_purge(&info->rx_queue); + } + spin_unlock_irqrestore(&ctc_tty_lock, saveflags); +} + +void +ctc_tty_cleanup(void) { + unsigned long saveflags; + + DBF_TEXT(trace, 2, __FUNCTION__); + spin_lock_irqsave(&ctc_tty_lock, saveflags); + ctc_tty_shuttingdown = 1; + spin_unlock_irqrestore(&ctc_tty_lock, saveflags); + tty_unregister_driver(driver->ctc_tty_device); + put_tty_driver(driver->ctc_tty_device); + kfree(driver); + driver = NULL; +} |