{ "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO |
                  UART_STARTECH },
        { "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO},
-       { 0, 0}
+       { NULL, 0}
 };
 
 struct tty_driver *hp_simserial_driver;
 
                if (info->xmit.buf) {
                        free_page((unsigned long) info->xmit.buf);
-                       info->xmit.buf = 0;
+                       info->xmit.buf = NULL;
                }
 
                if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
        if (tty->driver->flush_buffer) tty->driver->flush_buffer(tty);
        if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty);
        info->event = 0;
-       info->tty = 0;
+       info->tty = NULL;
        if (info->blocked_open) {
                if (info->close_delay)
                        schedule_timeout_interruptible(info->close_delay);
        info->event = 0;
        state->count = 0;
        info->flags &= ~ASYNC_NORMAL_ACTIVE;
-       info->tty = 0;
+       info->tty = NULL;
        wake_up_interruptible(&info->open_wait);
 }
 
        /*
         * Insert serial port into IRQ chain.
         */
-       info->prev_port = 0;
+       info->prev_port = NULL;
        info->next_port = IRQ_ports[state->irq];
        if (info->next_port)
                info->next_port->prev_port = info;