+ if (info->port.xmit_buf)
+ free_page(page);
+ else
+ info->port.xmit_buf = (unsigned char *) page;
+
+ /*
+ * Clear the FIFO buffers and disable them
+ * (they will be reenabled in mxser_change_speed())
+ */
+ if (info->board->chip_flag)
+ outb((UART_FCR_CLEAR_RCVR |
+ UART_FCR_CLEAR_XMIT |
+ MOXA_MUST_FCR_GDA_MODE_ENABLE), info->ioaddr + UART_FCR);
+ else
+ outb((UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT),
+ info->ioaddr + UART_FCR);
+
+ /*
+ * At this point there's no way the LSR could still be 0xFF;
+ * if it is, then bail out, because there's likely no UART
+ * here.
+ */
+ if (inb(info->ioaddr + UART_LSR) == 0xff) {
+ spin_unlock_irqrestore(&info->slock, flags);
+ if (capable(CAP_SYS_ADMIN)) {
+ if (tty)
+ set_bit(TTY_IO_ERROR, &tty->flags);
+ return 0;
+ } else
+ return -ENODEV;
+ }
+
+ /*
+ * Clear the interrupt registers.
+ */
+ (void) inb(info->ioaddr + UART_LSR);
+ (void) inb(info->ioaddr + UART_RX);
+ (void) inb(info->ioaddr + UART_IIR);
+ (void) inb(info->ioaddr + UART_MSR);
+
+ /*
+ * Now, initialize the UART
+ */
+ outb(UART_LCR_WLEN8, info->ioaddr + UART_LCR); /* reset DLAB */
+ info->MCR = UART_MCR_DTR | UART_MCR_RTS;
+ outb(info->MCR, info->ioaddr + UART_MCR);
+
+ /*
+ * Finally, enable interrupts
+ */
+ info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
+
+ if (info->board->chip_flag)
+ info->IER |= MOXA_MUST_IER_EGDAI;
+ outb(info->IER, info->ioaddr + UART_IER); /* enable interrupts */
+
+ /*
+ * And clear the interrupt registers again for luck.
+ */
+ (void) inb(info->ioaddr + UART_LSR);
+ (void) inb(info->ioaddr + UART_RX);
+ (void) inb(info->ioaddr + UART_IIR);
+ (void) inb(info->ioaddr + UART_MSR);
+
+ clear_bit(TTY_IO_ERROR, &tty->flags);
+ info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+
+ /*
+ * and set the speed of the serial port
+ */
+ mxser_change_speed(tty, NULL);
+ info->port.flags |= ASYNC_INITIALIZED;
+ spin_unlock_irqrestore(&info->slock, flags);
+
+ return 0;
+}
+
+/*
+ * This routine will shutdown a serial port; interrupts maybe disabled, and
+ * DTR is dropped if the hangup on close termio flag is on.
+ */
+static void mxser_shutdown(struct tty_struct *tty)
+{
+ struct mxser_port *info = tty->driver_data;
+ unsigned long flags;
+
+ if (!(info->port.flags & ASYNC_INITIALIZED))
+ return;
+
+ spin_lock_irqsave(&info->slock, flags);
+
+ /*
+ * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
+ * here so the queue might never be waken up
+ */
+ wake_up_interruptible(&info->delta_msr_wait);
+
+ /*
+ * Free the IRQ, if necessary
+ */
+ if (info->port.xmit_buf) {
+ free_page((unsigned long) info->port.xmit_buf);
+ info->port.xmit_buf = NULL;
+ }
+
+ info->IER = 0;
+ outb(0x00, info->ioaddr + UART_IER);
+
+ if (tty->termios->c_cflag & HUPCL)
+ info->MCR &= ~(UART_MCR_DTR | UART_MCR_RTS);
+ outb(info->MCR, info->ioaddr + UART_MCR);
+
+ /* clear Rx/Tx FIFO's */
+ if (info->board->chip_flag)
+ outb(UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT |
+ MOXA_MUST_FCR_GDA_MODE_ENABLE,
+ info->ioaddr + UART_FCR);
+ else
+ outb(UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
+ info->ioaddr + UART_FCR);
+
+ /* read data port to reset things */
+ (void) inb(info->ioaddr + UART_RX);
+
+ set_bit(TTY_IO_ERROR, &tty->flags);
+
+ info->port.flags &= ~ASYNC_INITIALIZED;
+
+ if (info->board->chip_flag)
+ SET_MOXA_MUST_NO_SOFTWARE_FLOW_CONTROL(info->ioaddr);
+
+ spin_unlock_irqrestore(&info->slock, flags);
+}
+
+/*
+ * 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 mxser_open(struct tty_struct *tty, struct file *filp)
+{
+ struct mxser_port *info;
+ unsigned long flags;
+ int retval, line;
+
+ line = tty->index;
+ if (line == MXSER_PORTS)
+ return 0;
+ if (line < 0 || line > MXSER_PORTS)
+ return -ENODEV;
+ info = &mxser_boards[line / MXSER_PORTS_PER_BOARD].ports[line % MXSER_PORTS_PER_BOARD];
+ if (!info->ioaddr)
+ return -ENODEV;
+
+ tty->driver_data = info;
+ tty_port_tty_set(&info->port, tty);
+ /*
+ * Start up serial port
+ */
+ spin_lock_irqsave(&info->port.lock, flags);
+ info->port.count++;
+ spin_unlock_irqrestore(&info->port.lock, flags);
+ retval = mxser_startup(tty);
+ if (retval)
+ return retval;
+
+ retval = tty_port_block_til_ready(&info->port, tty, filp);
+ if (retval)
+ return retval;
+
+ /* unmark here for very high baud rate (ex. 921600 bps) used */
+ tty->low_latency = 1;
+ return 0;
+}
+
+static void mxser_flush_buffer(struct tty_struct *tty)
+{
+ struct mxser_port *info = tty->driver_data;
+ char fcr;
+ unsigned long flags;
+
+
+ spin_lock_irqsave(&info->slock, flags);
+ info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+
+ fcr = inb(info->ioaddr + UART_FCR);
+ outb((fcr | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT),
+ info->ioaddr + UART_FCR);
+ outb(fcr, info->ioaddr + UART_FCR);
+
+ spin_unlock_irqrestore(&info->slock, flags);
+
+ tty_wakeup(tty);
+}
+
+
+/*
+ * This routine is called when the serial port gets closed. First, we
+ * wait for the last remaining data to be sent. Then, we unlink its
+ * async structure from the interrupt chain if necessary, and we free
+ * that IRQ if nothing is left in the chain.
+ */
+static void mxser_close(struct tty_struct *tty, struct file *filp)
+{
+ struct mxser_port *info = tty->driver_data;
+ struct tty_port *port = &info->port;
+
+ unsigned long timeout;
+
+ if (tty->index == MXSER_PORTS)
+ return;
+ if (!info)
+ return;
+
+ if (tty_port_close_start(port, tty, filp) == 0)
+ return;
+