if (tty->flags & (1 << TTY_IO_ERROR))
                return -EIO;
 
+       lock_kernel();
 #ifdef ISDN_DEBUG_MODEM_IOCTL
        printk(KERN_DEBUG "ttyI%d ioctl TIOCMGET\n", info->line);
 #endif
 
        control = info->mcr;
        status = info->msr;
+       unlock_kernel();
        return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
            | ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
            | ((status & UART_MSR_DCD) ? TIOCM_CAR : 0)
        printk(KERN_DEBUG "ttyI%d ioctl TIOCMxxx: %x %x\n", info->line, set, clear);
 #endif
 
+       lock_kernel();
        if (set & TIOCM_RTS)
                info->mcr |= UART_MCR_RTS;
        if (set & TIOCM_DTR) {
                        isdn_tty_modem_hup(info, 1);
                }
        }
+       unlock_kernel();
        return 0;
 }
 
                                return retval;
                        tty_wait_until_sent(tty, 0);
                        return 0;
-               case TIOCGSOFTCAR:
-#ifdef ISDN_DEBUG_MODEM_IOCTL
-                       printk(KERN_DEBUG "ttyI%d ioctl TIOCGSOFTCAR\n", info->line);
-#endif
-                       return put_user(C_CLOCAL(tty) ? 1 : 0, (ulong __user *) arg);
-               case TIOCSSOFTCAR:
-#ifdef ISDN_DEBUG_MODEM_IOCTL
-                       printk(KERN_DEBUG "ttyI%d ioctl TIOCSSOFTCAR\n", info->line);
-#endif
-                       if (get_user(arg, (ulong __user *) arg))
-                               return -EFAULT;
-                       tty->termios->c_cflag =
-                           ((tty->termios->c_cflag & ~CLOCAL) |
-                            (arg ? CLOCAL : 0));
-                       return 0;
                case TIOCSERGETLSR:     /* Get line status register */
 #ifdef ISDN_DEBUG_MODEM_IOCTL
                        printk(KERN_DEBUG "ttyI%d ioctl TIOCSERGETLSR\n", info->line);
        if (!old_termios)
                isdn_tty_change_speed(info);
        else {
-               if (tty->termios->c_cflag == old_termios->c_cflag)
+               if (tty->termios->c_cflag == old_termios->c_cflag &&
+                   tty->termios->c_ispeed == old_termios->c_ispeed &&
+                   tty->termios->c_ospeed == old_termios->c_ospeed)
                        return;
                isdn_tty_change_speed(info);
                if ((old_termios->c_cflag & CRTSCTS) &&
-                   !(tty->termios->c_cflag & CRTSCTS)) {
+                   !(tty->termios->c_cflag & CRTSCTS))
                        tty->hw_stopped = 0;
-               }
        }
 }