/* * generic_serial.c * * Copyright (C) 1998/1999 R.E.Wolff@BitWizard.nl * * written for the SX serial driver. * Contains the code that should be shared over all the serial drivers. * * Credit for the idea to do it this way might go to Alan Cox. * * * Version 0.1 -- December, 1998. Initial version. * Version 0.2 -- March, 1999. Some more routines. Bugfixes. Etc. * Version 0.5 -- August, 1999. Some more fixes. Reformat for Linus. * * BitWizard is actively maintaining this file. We sometimes find * that someone submitted changes to this file. We really appreciate * your help, but please submit changes through us. We're doing our * best to be responsive. -- REW * */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/tty.h> #include <linux/serial.h> #include <linux/mm.h> #include <linux/generic_serial.h> #include <linux/interrupt.h> #include <linux/tty_flip.h> #include <linux/delay.h> #include <asm/semaphore.h> #include <asm/uaccess.h> #define DEBUG static int gs_debug; #ifdef DEBUG #define gs_dprintk(f, str...) if (gs_debug & f) printk (str) #else #define gs_dprintk(f, str...) /* nothing */ #endif #define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter %s\n", __FUNCTION__) #define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit %s\n", __FUNCTION__) #define NEW_WRITE_LOCKING 1 #if NEW_WRITE_LOCKING #define DECL /* Nothing */ #define LOCKIT mutex_lock(& port->port_write_mutex); #define RELEASEIT mutex_unlock(&port->port_write_mutex); #else #define DECL unsigned long flags; #define LOCKIT save_flags (flags);cli () #define RELEASEIT restore_flags (flags) #endif #define RS_EVENT_WRITE_WAKEUP 1 module_param(gs_debug, int, 0644); void gs_put_char(struct tty_struct * tty, unsigned char ch) { struct gs_port *port; DECL func_enter (); if (!tty) return; port = tty->driver_data; if (!port) return; if (! (port->flags & ASYNC_INITIALIZED)) return; /* Take a lock on the serial tranmit buffer! */ LOCKIT; if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) { /* Sorry, buffer is full, drop character. Update statistics???? -- REW */ RELEASEIT; return; } port->xmit_buf[port->xmit_head++] = ch; port->xmit_head &= SERIAL_XMIT_SIZE - 1; port->xmit_cnt++; /* Characters in buffer */ RELEASEIT; func_exit (); } #ifdef NEW_WRITE_LOCKING /* > Problems to take into account are: > -1- Interrupts that empty part of the buffer. > -2- page faults on the access to userspace. > -3- Other processes that are also trying to do a "write". */ int gs_write(struct tty_struct * tty, const unsigned char *buf, int count) { struct gs_port *port; int c, total = 0; int t; func_enter (); if (!tty) return 0; port = tty->driver_data; if (!port) return 0; if (! (port->flags & ASYNC_INITIALIZED)) return 0; /* get exclusive "write" access to this port (problem 3) */ /* This is not a spinlock because we can have a disk access (page fault) in copy_from_user */ mutex_lock(& port->port_write_mutex); while (1) { c = count; /* This is safe because we "OWN" the "head". Noone else can change the "head": we own the port_write_mutex. */ /* Don't overrun the end of the buffer */ t = SERIAL_XMIT_SIZE - port->xmit_head; if (t < c) c = t; /* This is safe because the xmit_cnt can only decrease. This would increase "t", so we might copy too little chars. */ /* Don't copy past the "head" of the buffer */ t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; if (t < c) c = t; /* Can't copy more? break out! */ if (c <= 0) break; memcpy (port->xmit_buf + port->xmit_head, buf, c); port -> xmit_cnt += c; port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1); buf += c; count -= c; total += c; } mutex_unlock(& port->port_write_mutex); gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n", (port->flags & GS_TX_INTEN)?"enabled": "disabled"); if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped && !(port->flags & GS_TX_INTEN)) { port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); } func_exit (); return total; } #else /* > Problems to take into account are: > -1- Interrupts that empty part of the buffer. > -2- page faults on the access to userspace. > -3- Other processes that are also trying to do a "write". */ int gs_write(struct tty_struct * tty, const unsigned char *buf, int count) { struct gs_port *port; int c, total = 0; int t; unsigned long flags; func_enter (); /* The standard serial driver returns 0 in this case. That sounds to me as "No error, I just didn't get to writing any bytes. Feel free to try again." The "official" way to write n bytes from buf is: for (nwritten = 0;nwritten < n;nwritten += rv) { rv = write (fd, buf+nwritten, n-nwritten); if (rv < 0) break; // Error: bail out. // } which will loop endlessly in this case. The manual page for write agrees with me. In practise almost everybody writes "write (fd, buf,n);" but some people might have had to deal with incomplete writes in the past and correctly implemented it by now... */ if (!tty) return -EIO; port = tty->driver_data; if (!port || !port->xmit_buf) return -EIO; local_save_flags(flags); while (1) { cli(); c = count; /* This is safe because we "OWN" the "head". Noone else can change the "head": we own the port_write_mutex. */ /* Don't overrun the end of the buffer */ t = SERIAL_XMIT_SIZE - port->xmit_head; if (t < c) c = t; /* This is safe because the xmit_cnt can only decrease. This would increase "t", so we might copy too little chars. */ /* Don't copy past the "head" of the buffer */ t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; if (t < c) c = t; /* Can't copy more? break out! */ if (c <= 0) { local_restore_flags(flags); break; } memcpy(port->xmit_buf + port->xmit_head, buf, c); port->xmit_head = ((port->xmit_head + c) & (SERIAL_XMIT_SIZE-1)); port->xmit_cnt += c; local_restore_flags(flags); buf += c; count -= c; total += c; } if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped && !(port->flags & GS_TX_INTEN)) { port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); } func_exit (); return total; } #endif int gs_write_room(struct tty_struct * tty) { struct gs_port *port = tty->driver_data; int ret; func_enter (); ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1; if (ret < 0) ret = 0; func_exit (); return ret; } int gs_chars_in_buffer(struct tty_struct *tty) { struct gs_port *port = tty->driver_data; func_enter (); func_exit (); return port->xmit_cnt; } static int gs_real_chars_in_buffer(struct tty_struct *tty) { struct gs_port *port; func_enter (); if (!tty) return 0; port = tty->driver_data; if (!port->rd) return 0; if (!port->rd->chars_in_buffer) return 0; func_exit (); return port->xmit_cnt + port->rd->chars_in_buffer (port); } static int gs_wait_tx_flushed (void * ptr, unsigned long timeout) { struct gs_port *port = ptr; unsigned long end_jiffies; int jiffies_to_transmit, charsleft = 0, rv = 0; int rcib; func_enter(); gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port); if (port) { gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n", port->xmit_cnt, port->xmit_buf, port->tty); } if (!port || port->xmit_cnt < 0 || !port->xmit_buf) { gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n"); func_exit(); return -EINVAL; /* This is an error which we don't know how to handle. */ } rcib = gs_real_chars_in_buffer(port->tty); if(rcib <= 0) { gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n"); func_exit(); return rv; } /* stop trying: now + twice the time it would normally take + seconds */ if (timeout == 0) timeout = MAX_SCHEDULE_TIMEOUT; end_jiffies = jiffies; if (timeout != MAX_SCHEDULE_TIMEOUT) end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0; end_jiffies += timeout; gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n", jiffies, end_jiffies, end_jiffies-jiffies); /* the expression is actually jiffies < end_jiffies, but that won't work around the wraparound. Tricky eh? */ while ((charsleft = gs_real_chars_in_buffer (port->tty)) && time_after (end_jiffies, jiffies)) { /* Units check: chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies! check! */ charsleft += 16; /* Allow 16 chars more to be transmitted ... */ jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0; /* ^^^ Round up.... */ if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1; gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies " "(%d chars).\n", jiffies_to_transmit, charsleft); msleep_interruptible(jiffies_to_msecs(jiffies_to_transmit)); if (signal_pending (current)) { gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: "); rv = -EINTR; break; } } gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft); set_current_state (TASK_RUNNING); func_exit(); return rv; } void gs_flush_buffer(struct tty_struct *tty) { struct gs_port *port; unsigned long flags; func_enter (); if (!tty) return; port = tty->driver_data; if (!port) return; /* XXX Would the write semaphore do? */ spin_lock_irqsave (&port->driver_lock, flags); port->xmit_cnt = port->xmit_head = port->xmit_tail = 0; spin_unlock_irqrestore (&port->driver_lock, flags); tty_wakeup(tty); func_exit (); } void gs_flush_chars(struct tty_struct * tty) { struct gs_port *port; func_enter (); if (!tty) return; port = tty->driver_data; if (!port) return; if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped || !port->xmit_buf) { func_exit (); return; } /* Beats me -- REW */ port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); func_exit (); } void gs_stop(struct tty_struct * tty) { struct gs_port *port; func_enter (); if (!tty) return; port = tty->driver_data; if (!port) return; if (port->xmit_cnt && port->xmit_buf && (port->flags & GS_TX_INTEN) ) { port->flags &= ~GS_TX_INTEN; port->rd->disable_tx_interrupts (port); } func_exit (); } void gs_start(struct tty_struct * tty) { struct gs_port *port; if (!tty) return; port = tty->driver_data; if (!port) return; if (port->xmit_cnt && port->xmit_buf && !(port->flags & GS_TX_INTEN) ) { port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); } func_exit (); } static void gs_shutdown_port (struct gs_port *port) { unsigned long flags; func_enter(); if (!port) return; if (!(port->flags & ASYNC_INITIALIZED)) return; spin_lock_irqsave(&port->driver_lock, flags); if (port->xmit_buf) { free_page((unsigned long) port->xmit_buf); port->xmit_buf = NULL; } if (port->tty) set_bit(TTY_IO_ERROR, &port->tty->flags); port->rd->shutdown_port (port); port->flags &= ~ASYNC_INITIALIZED; spin_unlock_irqrestore(&port->driver_lock, flags); func_exit(); } void gs_hangup(struct tty_struct *tty) { struct gs_port *port; func_enter (); if (!tty) return; port = tty->driver_data; tty = port->tty; if (!tty) return; gs_shutdown_port (port); port->flags &= ~(ASYNC_NORMAL_ACTIVE|GS_ACTIVE); port->tty = NULL; port->count = 0; wake_up_interruptible(&port->open_wait); func_exit (); } int gs_block_til_ready(void *port_, struct file * filp) { struct gs_port *port = port_; DECLARE_WAITQUEUE(wait, current); int retval; int do_clocal = 0; int CD; struct tty_struct *tty; unsigned long flags; func_enter (); if (!port) return 0; tty = port->tty; if (!tty) return 0; gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n"); /* * 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) || port->flags & ASYNC_CLOSING) { interruptible_sleep_on(&port->close_wait); if (port->flags & ASYNC_HUP_NOTIFY) return -EAGAIN; else return -ERESTARTSYS; } gs_dprintk (GS_DEBUG_BTR, "after hung up\n"); /* * If non-blocking mode is set, or the port is not enabled, * then make the check up front and then exit. */ if ((filp->f_flags & O_NONBLOCK) || (tty->flags & (1 << TTY_IO_ERROR))) { port->flags |= ASYNC_NORMAL_ACTIVE; return 0; } gs_dprintk (GS_DEBUG_BTR, "after nonblock\n"); if (C_CLOCAL(tty)) 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, port->count is dropped by one, so that * rs_close() knows when to free things. We restore it upon * exit, either normal or abnormal. */ retval = 0; add_wait_queue(&port->open_wait, &wait); gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n"); spin_lock_irqsave(&port->driver_lock, flags); if (!tty_hung_up_p(filp)) { port->count--; } spin_unlock_irqrestore(&port->driver_lock, flags); port->blocked_open++; while (1) { CD = port->rd->get_CD (port); gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD); set_current_state (TASK_INTERRUPTIBLE); if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) { if (port->flags & ASYNC_HUP_NOTIFY) retval = -EAGAIN; else retval = -ERESTARTSYS; break; } if (!(port->flags & ASYNC_CLOSING) && (do_clocal || CD)) break; gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n", (int)signal_pending (current), *(long*)(¤t->blocked)); if (signal_pending(current)) { retval = -ERESTARTSYS; break; } schedule(); } gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n", port->blocked_open); set_current_state (TASK_RUNNING); remove_wait_queue(&port->open_wait, &wait); if (!tty_hung_up_p(filp)) { port->count++; } port->blocked_open--; if (retval) return retval; port->flags |= ASYNC_NORMAL_ACTIVE; func_exit (); return 0; } void gs_close(struct tty_struct * tty, struct file * filp) { unsigned long flags; struct gs_port *port; func_enter (); if (!tty) return; port = (struct gs_port *) tty->driver_data; if (!port) return; if (!port->tty) { /* This seems to happen when this is called from vhangup. */ gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->tty is NULL\n"); port->tty = tty; } spin_lock_irqsave(&port->driver_lock, flags); if (tty_hung_up_p(filp)) { spin_unlock_irqrestore(&port->driver_lock, flags); if (port->rd->hungup) port->rd->hungup (port); func_exit (); return; } if ((tty->count == 1) && (port->count != 1)) { printk(KERN_ERR "gs: gs_close port %p: bad port count;" " tty->count is 1, port count is %d\n", port, port->count); port->count = 1; } if (--port->count < 0) { printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->count); port->count = 0; } if (port->count) { gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->count); spin_unlock_irqrestore(&port->driver_lock, flags); func_exit (); return; } port->flags |= ASYNC_CLOSING; /* * Now we wait for the transmit buffer to clear; and we notify * the line discipline to only process XON/XOFF characters. */ tty->closing = 1; /* if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) tty_wait_until_sent(tty, port->closing_wait); */ /* * 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. */ port->rd->disable_rx_interrupts (port); spin_unlock_irqrestore(&port->driver_lock, flags); /* close has no way of returning "EINTR", so discard return value */ if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) gs_wait_tx_flushed (port, port->closing_wait); port->flags &= ~GS_ACTIVE; if (tty->driver->flush_buffer) tty->driver->flush_buffer(tty); tty_ldisc_flush(tty); tty->closing = 0; port->event = 0; port->rd->close (port); port->rd->shutdown_port (port); port->tty = NULL; if (port->blocked_open) { if (port->close_delay) { spin_unlock_irqrestore(&port->driver_lock, flags); msleep_interruptible(jiffies_to_msecs(port->close_delay)); spin_lock_irqsave(&port->driver_lock, flags); } wake_up_interruptible(&port->open_wait); } port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED); wake_up_interruptible(&port->close_wait); func_exit (); } void gs_set_termios (struct tty_struct * tty, struct ktermios * old_termios) { struct gs_port *port; int baudrate, tmp, rv; struct ktermios *tiosp; func_enter(); if (!tty) return; port = tty->driver_data; if (!port) return; if (!port->tty) { /* This seems to happen when this is called after gs_close. */ gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->tty is NULL\n"); port->tty = tty; } tiosp = tty->termios; if (gs_debug & GS_DEBUG_TERMIOS) { gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp); } /* This is an optimization that is only allowed for dumb cards */ /* Smart cards require knowledge of iflags and oflags too: that might change hardware cooking mode.... */ if (old_termios) { if( (tiosp->c_iflag == old_termios->c_iflag) && (tiosp->c_oflag == old_termios->c_oflag) && (tiosp->c_cflag == old_termios->c_cflag) && (tiosp->c_lflag == old_termios->c_lflag) && (tiosp->c_line == old_termios->c_line) && (memcmp(tiosp->c_cc, old_termios->c_cc, NCC) == 0)) { gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: optimized away\n"); return /* 0 */; } } else gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: no old_termios: " "no optimization\n"); if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) { if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n"); if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n"); if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n"); if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n"); if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n"); if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n"); } baudrate = tty_get_baud_rate(tty); if ((tiosp->c_cflag & CBAUD) == B38400) { if ( (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI) baudrate = 57600; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI) baudrate = 115200; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI) baudrate = 230400; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP) baudrate = 460800; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) baudrate = (port->baud_base / port->custom_divisor); } /* I recommend using THIS instead of the mess in termios (and duplicating the above code). Next we should create a clean interface towards this variable. If your card supports arbitrary baud rates, (e.g. CD1400 or 16550 based cards) then everything will be very easy..... */ port->baud = baudrate; /* Two timer ticks seems enough to wakeup something like SLIP driver */ /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */ tmp = (baudrate / 10 / HZ) * 2; if (tmp < 0) tmp = 0; if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1; port->wakeup_chars = tmp; /* We should really wait for the characters to be all sent before changing the settings. -- CAL */ rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT); if (rv < 0) return /* rv */; rv = port->rd->set_real_termios(port); if (rv < 0) return /* rv */; if ((!old_termios || (old_termios->c_cflag & CRTSCTS)) && !( tiosp->c_cflag & CRTSCTS)) { tty->stopped = 0; gs_start(tty); } #ifdef tytso_patch_94Nov25_1726 /* This "makes sense", Why is it commented out? */ if (!(old_termios->c_cflag & CLOCAL) && (tty->termios->c_cflag & CLOCAL)) wake_up_interruptible(&port->gs.open_wait); #endif func_exit(); return /* 0 */; } /* Must be called with interrupts enabled */ int gs_init_port(struct gs_port *port) { unsigned long flags; func_enter (); if (port->flags & ASYNC_INITIALIZED) { func_exit (); return 0; } if (!port->xmit_buf) { /* We may sleep in get_zeroed_page() */ unsigned long tmp; tmp = get_zeroed_page(GFP_KERNEL); spin_lock_irqsave (&port->driver_lock, flags); if (port->xmit_buf) free_page (tmp); else port->xmit_buf = (unsigned char *) tmp; spin_unlock_irqrestore(&port->driver_lock, flags); if (!port->xmit_buf) { func_exit (); return -ENOMEM; } } spin_lock_irqsave (&port->driver_lock, flags); if (port->tty) clear_bit(TTY_IO_ERROR, &port->tty->flags); mutex_init(&port->port_write_mutex); port->xmit_cnt = port->xmit_head = port->xmit_tail = 0; spin_unlock_irqrestore(&port->driver_lock, flags); gs_set_termios(port->tty, NULL); spin_lock_irqsave (&port->driver_lock, flags); port->flags |= ASYNC_INITIALIZED; port->flags &= ~GS_TX_INTEN; spin_unlock_irqrestore(&port->driver_lock, flags); func_exit (); return 0; } int gs_setserial(struct gs_port *port, struct serial_struct __user *sp) { struct serial_struct sio; if (copy_from_user(&sio, sp, sizeof(struct serial_struct))) return(-EFAULT); if (!capable(CAP_SYS_ADMIN)) { if ((sio.baud_base != port->baud_base) || (sio.close_delay != port->close_delay) || ((sio.flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) return(-EPERM); } port->flags = (port->flags & ~ASYNC_USR_MASK) | (sio.flags & ASYNC_USR_MASK); port->baud_base = sio.baud_base; port->close_delay = sio.close_delay; port->closing_wait = sio.closing_wait; port->custom_divisor = sio.custom_divisor; gs_set_termios (port->tty, NULL); return 0; } /*****************************************************************************/ /* * Generate the serial struct info. */ int gs_getserial(struct gs_port *port, struct serial_struct __user *sp) { struct serial_struct sio; memset(&sio, 0, sizeof(struct serial_struct)); sio.flags = port->flags; sio.baud_base = port->baud_base; sio.close_delay = port->close_delay; sio.closing_wait = port->closing_wait; sio.custom_divisor = port->custom_divisor; sio.hub6 = 0; /* If you want you can override these. */ sio.type = PORT_UNKNOWN; sio.xmit_fifo_size = -1; sio.line = -1; sio.port = -1; sio.irq = -1; if (port->rd->getserial) port->rd->getserial (port, &sio); if (copy_to_user(sp, &sio, sizeof(struct serial_struct))) return -EFAULT; return 0; } void gs_got_break(struct gs_port *port) { func_enter (); tty_insert_flip_char(port->tty, 0, TTY_BREAK); tty_schedule_flip(port->tty); if (port->flags & ASYNC_SAK) { do_SAK (port->tty); } func_exit (); } EXPORT_SYMBOL(gs_put_char); EXPORT_SYMBOL(gs_write); EXPORT_SYMBOL(gs_write_room); EXPORT_SYMBOL(gs_chars_in_buffer); EXPORT_SYMBOL(gs_flush_buffer); EXPORT_SYMBOL(gs_flush_chars); EXPORT_SYMBOL(gs_stop); EXPORT_SYMBOL(gs_start); EXPORT_SYMBOL(gs_hangup); EXPORT_SYMBOL(gs_block_til_ready); EXPORT_SYMBOL(gs_close); EXPORT_SYMBOL(gs_set_termios); EXPORT_SYMBOL(gs_init_port); EXPORT_SYMBOL(gs_setserial); EXPORT_SYMBOL(gs_getserial); EXPORT_SYMBOL(gs_got_break); MODULE_LICENSE("GPL");