- DECLARE_WAITQUEUE(wait, current);
- int retval;
- bool do_clocal = false;
- bool extra_count = false;
- unsigned long flags;
-
- if (debug_level >= DEBUG_LEVEL_INFO)
- printk("%s(%d):block_til_ready on %s\n",
- __FILE__,__LINE__, tty->driver->name );
-
- if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
- /* nonblock mode is set or port is not enabled */
- /* just verify that callout device is not active */
- info->flags |= ASYNC_NORMAL_ACTIVE;
- return 0;
- }
-
- if (tty->termios->c_cflag & CLOCAL)
- do_clocal = true;
-
- /* Wait for 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
- * mgslpc_close() knows when to free things. We restore it upon
- * exit, either normal or abnormal.
- */
-
- retval = 0;
- add_wait_queue(&info->open_wait, &wait);
-
- if (debug_level >= DEBUG_LEVEL_INFO)
- printk("%s(%d):block_til_ready before block on %s count=%d\n",
- __FILE__,__LINE__, tty->driver->name, info->count );
-
- spin_lock_irqsave(&info->lock, flags);
- if (!tty_hung_up_p(filp)) {
- extra_count = true;
- info->count--;
- }
- spin_unlock_irqrestore(&info->lock, flags);
- info->blocked_open++;
-
- while (1) {
- if ((tty->termios->c_cflag & CBAUD)) {
- spin_lock_irqsave(&info->lock,flags);
- info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
- set_signals(info);
- spin_unlock_irqrestore(&info->lock,flags);
- }
-
- set_current_state(TASK_INTERRUPTIBLE);
-
- if (tty_hung_up_p(filp) || !(info->flags & ASYNC_INITIALIZED)){
- retval = (info->flags & ASYNC_HUP_NOTIFY) ?
- -EAGAIN : -ERESTARTSYS;
- break;
- }
-
- spin_lock_irqsave(&info->lock,flags);
- get_signals(info);
- spin_unlock_irqrestore(&info->lock,flags);
-
- if (!(info->flags & ASYNC_CLOSING) &&
- (do_clocal || (info->serial_signals & SerialSignal_DCD)) ) {
- break;
- }
-
- if (signal_pending(current)) {
- retval = -ERESTARTSYS;
- break;
- }
-
- if (debug_level >= DEBUG_LEVEL_INFO)
- printk("%s(%d):block_til_ready blocking on %s count=%d\n",
- __FILE__,__LINE__, tty->driver->name, info->count );
-
- schedule();
- }
-
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&info->open_wait, &wait);