[ARM] 3571/1: netX: serial driver for Hilscher netX

Patch from Sascha Hauer

This patch adds the serial driver for Hilscher's netX network
processors.

Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 749 insertions, 0 deletions

diff --git a/drivers/serial/netx-serial.c b/drivers/serial/netx-serial.c
new file mode 100644
index 0000000..c1adc9e
--- /dev/null
+++ b/drivers/serial/netx-serial.c
@@ -0,0 +1,749 @@
+/*
+ * drivers/serial/netx-serial.c
+ *
+ * Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/config.h>
+
+#if defined(CONFIG_SERIAL_NETX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/platform_device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/hardware.h>
+#include <asm/arch/netx-regs.h>
+
+/* We've been assigned a range on the "Low-density serial ports" major */
+#define SERIAL_NX_MAJOR	204
+#define MINOR_START	170
+
+#ifdef CONFIG_SERIAL_NETX_CONSOLE
+
+enum uart_regs {
+	UART_DR              = 0x00,
+	UART_SR              = 0x04,
+	UART_LINE_CR         = 0x08,
+	UART_BAUDDIV_MSB     = 0x0c,
+	UART_BAUDDIV_LSB     = 0x10,
+	UART_CR              = 0x14,
+	UART_FR              = 0x18,
+	UART_IIR             = 0x1c,
+	UART_ILPR            = 0x20,
+	UART_RTS_CR          = 0x24,
+	UART_RTS_LEAD        = 0x28,
+	UART_RTS_TRAIL       = 0x2c,
+	UART_DRV_ENABLE      = 0x30,
+	UART_BRM_CR          = 0x34,
+	UART_RXFIFO_IRQLEVEL = 0x38,
+	UART_TXFIFO_IRQLEVEL = 0x3c,
+};
+
+#define SR_FE (1<<0)
+#define SR_PE (1<<1)
+#define SR_BE (1<<2)
+#define SR_OE (1<<3)
+
+#define LINE_CR_BRK       (1<<0)
+#define LINE_CR_PEN       (1<<1)
+#define LINE_CR_EPS       (1<<2)
+#define LINE_CR_STP2      (1<<3)
+#define LINE_CR_FEN       (1<<4)
+#define LINE_CR_5BIT      (0<<5)
+#define LINE_CR_6BIT      (1<<5)
+#define LINE_CR_7BIT      (2<<5)
+#define LINE_CR_8BIT      (3<<5)
+#define LINE_CR_BITS_MASK (3<<5)
+
+#define CR_UART_EN (1<<0)
+#define CR_SIREN   (1<<1)
+#define CR_SIRLP   (1<<2)
+#define CR_MSIE    (1<<3)
+#define CR_RIE     (1<<4)
+#define CR_TIE     (1<<5)
+#define CR_RTIE    (1<<6)
+#define CR_LBE     (1<<7)
+
+#define FR_CTS  (1<<0)
+#define FR_DSR  (1<<1)
+#define FR_DCD  (1<<2)
+#define FR_BUSY (1<<3)
+#define FR_RXFE (1<<4)
+#define FR_TXFF (1<<5)
+#define FR_RXFF (1<<6)
+#define FR_TXFE (1<<7)
+
+#define IIR_MIS (1<<0)
+#define IIR_RIS (1<<1)
+#define IIR_TIS (1<<2)
+#define IIR_RTIS (1<<3)
+#define IIR_MASK 0xf
+
+#define RTS_CR_AUTO (1<<0)
+#define RTS_CR_RTS  (1<<1)
+#define RTS_CR_COUNT (1<<2)
+#define RTS_CR_MOD2  (1<<3)
+#define RTS_CR_RTS_POL (1<<4)
+#define RTS_CR_CTS_CTR (1<<5)
+#define RTS_CR_CTS_POL (1<<6)
+#define RTS_CR_STICK   (1<<7)
+
+#define UART_PORT_SIZE 0x40
+#define DRIVER_NAME "netx-uart"
+
+struct netx_port {
+	struct uart_port	port;
+};
+
+static void netx_stop_tx(struct uart_port *port)
+{
+	unsigned int val;
+	val = readl(port->membase + UART_CR);
+	writel(val & ~CR_TIE,  port->membase + UART_CR);
+}
+
+static void netx_stop_rx(struct uart_port *port)
+{
+	unsigned int val;
+	val = readl(port->membase + UART_CR);
+	writel(val & ~CR_RIE,  port->membase + UART_CR);
+}
+
+static void netx_enable_ms(struct uart_port *port)
+{
+	unsigned int val;
+	val = readl(port->membase + UART_CR);
+	writel(val | CR_MSIE, port->membase + UART_CR);
+}
+
+static inline void netx_transmit_buffer(struct uart_port *port)
+{
+	struct circ_buf *xmit = &port->info->xmit;
+
+	if (port->x_char) {
+		writel(port->x_char, port->membase + UART_DR);
+		port->icount.tx++;
+		port->x_char = 0;
+		return;
+	}
+
+	if (uart_tx_stopped(port) || uart_circ_empty(xmit)) {
+		netx_stop_tx(port);
+		return;
+	}
+
+	do {
+		/* send xmit->buf[xmit->tail]
+		 * out the port here */
+		writel(xmit->buf[xmit->tail], port->membase + UART_DR);
+		xmit->tail = (xmit->tail + 1) &
+		         (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+		if (uart_circ_empty(xmit))
+			break;
+	} while (!(readl(port->membase + UART_FR) & FR_TXFF));
+
+	if (uart_circ_empty(xmit))
+		netx_stop_tx(port);
+}
+
+static void netx_start_tx(struct uart_port *port)
+{
+	writel(
+	    readl(port->membase + UART_CR) | CR_TIE, port->membase + UART_CR);
+
+	if (!(readl(port->membase + UART_FR) & FR_TXFF))
+		netx_transmit_buffer(port);
+}
+
+static unsigned int netx_tx_empty(struct uart_port *port)
+{
+	return readl(port->membase + UART_FR) & FR_BUSY ? 0 : TIOCSER_TEMT;
+}
+
+static void netx_txint(struct uart_port *port)
+{
+	struct circ_buf *xmit = &port->info->xmit;
+
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+		netx_stop_tx(port);
+		return;
+	}
+
+	netx_transmit_buffer(port);
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+}
+
+static void netx_rxint(struct uart_port *port, struct pt_regs *regs)
+{
+	unsigned char rx, flg, status;
+	struct tty_struct *tty = port->info->tty;
+
+	while (!(readl(port->membase + UART_FR) & FR_RXFE)) {
+		rx = readl(port->membase + UART_DR);
+		flg = TTY_NORMAL;
+		port->icount.rx++;
+		status = readl(port->membase + UART_SR);
+		if (status & SR_BE) {
+			writel(0, port->membase + UART_SR);
+			if (uart_handle_break(port))
+				continue;
+		}
+
+		if (unlikely(status & (SR_FE | SR_PE | SR_OE))) {
+
+			if (status & SR_PE)
+				port->icount.parity++;
+			else if (status & SR_FE)
+				port->icount.frame++;
+			if (status & SR_OE)
+				port->icount.overrun++;
+
+			status &= port->read_status_mask;
+
+			if (status & SR_BE)
+				flg = TTY_BREAK;
+			else if (status & SR_PE)
+				flg = TTY_PARITY;
+			else if (status & SR_FE)
+				flg = TTY_FRAME;
+		}
+
+		if (uart_handle_sysrq_char(port, rx, regs))
+			continue;
+
+		uart_insert_char(port, status, SR_OE, rx, flg);
+	}
+
+	tty_flip_buffer_push(tty);
+	return;
+}
+
+static irqreturn_t netx_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct uart_port *port = (struct uart_port *)dev_id;
+	unsigned long flags;
+	unsigned char status;
+
+	spin_lock_irqsave(&port->lock,flags);
+
+	status = readl(port->membase + UART_IIR) & IIR_MASK;
+	while (status) {
+		if (status & IIR_RIS)
+			netx_rxint(port, regs);
+		if (status & IIR_TIS)
+			netx_txint(port);
+		if (status & IIR_MIS) {
+			if (readl(port->membase + UART_FR) & FR_CTS)
+				uart_handle_cts_change(port, 1);
+			else
+				uart_handle_cts_change(port, 0);
+		}
+		writel(0, port->membase + UART_IIR);
+		status = readl(port->membase + UART_IIR) & IIR_MASK;
+	}
+
+	spin_unlock_irqrestore(&port->lock,flags);
+	return IRQ_HANDLED;
+}
+
+static unsigned int netx_get_mctrl(struct uart_port *port)
+{
+	unsigned int ret = TIOCM_DSR | TIOCM_CAR;
+
+	if (readl(port->membase + UART_FR) & FR_CTS)
+		ret |= TIOCM_CTS;
+
+	return ret;
+}
+
+static void netx_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	unsigned int val;
+
+	if (mctrl & TIOCM_RTS) {
+		val = readl(port->membase + UART_RTS_CR);
+		writel(val | RTS_CR_RTS, port->membase + UART_RTS_CR);
+	}
+}
+
+static void netx_break_ctl(struct uart_port *port, int break_state)
+{
+	unsigned int line_cr;
+	spin_lock_irq(&port->lock);
+
+	line_cr = readl(port->membase + UART_LINE_CR);
+	if (break_state != 0)
+		line_cr |= LINE_CR_BRK;
+	else
+		line_cr &= ~LINE_CR_BRK;
+	writel(line_cr, port->membase + UART_LINE_CR);
+
+	spin_unlock_irq(&port->lock);
+}
+
+static int netx_startup(struct uart_port *port)
+{
+	int ret;
+
+	ret = request_irq(port->irq, netx_int, 0,
+			     DRIVER_NAME, port);
+	if (ret) {
+		dev_err(port->dev, "unable to grab irq%d\n",port->irq);
+		goto exit;
+	}
+
+	writel(readl(port->membase + UART_LINE_CR) | LINE_CR_FEN,
+		port->membase + UART_LINE_CR);
+
+	writel(CR_MSIE | CR_RIE | CR_TIE | CR_RTIE | CR_UART_EN,
+		port->membase + UART_CR);
+
+exit:
+	return ret;
+}
+
+static void netx_shutdown(struct uart_port *port)
+{
+	writel(0, port->membase + UART_CR) ;
+
+	free_irq(port->irq, port);
+}
+
+static void
+netx_set_termios(struct uart_port *port, struct termios *termios,
+		   struct termios *old)
+{
+	unsigned int baud, quot;
+	unsigned char old_cr;
+	unsigned char line_cr = LINE_CR_FEN;
+	unsigned char rts_cr = 0;
+
+	switch (termios->c_cflag & CSIZE) {
+	case CS5:
+		line_cr |= LINE_CR_5BIT;
+		break;
+	case CS6:
+		line_cr |= LINE_CR_6BIT;
+		break;
+	case CS7:
+		line_cr |= LINE_CR_7BIT;
+		break;
+	case CS8:
+		line_cr |= LINE_CR_8BIT;
+		break;
+	}
+
+	if (termios->c_cflag & CSTOPB)
+		line_cr |= LINE_CR_STP2;
+
+	if (termios->c_cflag & PARENB) {
+		line_cr |= LINE_CR_PEN;
+		if (!(termios->c_cflag & PARODD))
+			line_cr |= LINE_CR_EPS;
+	}
+
+	if (termios->c_cflag & CRTSCTS)
+		rts_cr = RTS_CR_AUTO | RTS_CR_CTS_CTR | RTS_CR_RTS_POL;
+
+	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+	quot = baud * 4096;
+	quot /= 1000;
+	quot *= 256;
+	quot /= 100000;
+
+	spin_lock_irq(&port->lock);
+
+	uart_update_timeout(port, termios->c_cflag, baud);
+
+	old_cr = readl(port->membase + UART_CR);
+
+	/* disable interrupts */
+	writel(old_cr & ~(CR_MSIE | CR_RIE | CR_TIE | CR_RTIE),
+		port->membase + UART_CR);
+
+	/* drain transmitter */
+	while (readl(port->membase + UART_FR) & FR_BUSY);
+
+	/* disable UART */
+	writel(old_cr & ~CR_UART_EN, port->membase + UART_CR);
+
+	/* modem status interrupts */
+	old_cr &= ~CR_MSIE;
+	if (UART_ENABLE_MS(port, termios->c_cflag))
+		old_cr |= CR_MSIE;
+
+	writel((quot>>8) & 0xff, port->membase + UART_BAUDDIV_MSB);
+	writel(quot & 0xff, port->membase + UART_BAUDDIV_LSB);
+	writel(line_cr, port->membase + UART_LINE_CR);
+
+	writel(rts_cr, port->membase + UART_RTS_CR);
+
+	/*
+	 * Characters to ignore
+	 */
+	port->ignore_status_mask = 0;
+	if (termios->c_iflag & IGNPAR)
+		port->ignore_status_mask |= SR_PE;
+	if (termios->c_iflag & IGNBRK) {
+		port->ignore_status_mask |= SR_BE;
+		/*
+		 * If we're ignoring parity and break indicators,
+		 * ignore overruns too (for real raw support).
+		 */
+		if (termios->c_iflag & IGNPAR)
+			port->ignore_status_mask |= SR_PE;
+	}
+
+	port->read_status_mask = 0;
+	if (termios->c_iflag & (BRKINT | PARMRK))
+		port->read_status_mask |= SR_BE;
+	if (termios->c_iflag & INPCK)
+		port->read_status_mask |= SR_PE | SR_FE;
+
+	writel(old_cr, port->membase + UART_CR);
+
+	spin_unlock_irq(&port->lock);
+}
+
+static const char *netx_type(struct uart_port *port)
+{
+	return port->type == PORT_NETX ? "NETX" : NULL;
+}
+
+static void netx_release_port(struct uart_port *port)
+{
+	release_mem_region(port->mapbase, UART_PORT_SIZE);
+}
+
+static int netx_request_port(struct uart_port *port)
+{
+	return request_mem_region(port->mapbase, UART_PORT_SIZE,
+			DRIVER_NAME) != NULL ? 0 : -EBUSY;
+}
+
+static void netx_config_port(struct uart_port *port, int flags)
+{
+	if (flags & UART_CONFIG_TYPE && netx_request_port(port) == 0)
+		port->type = PORT_NETX;
+}
+
+static int
+netx_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+	int ret = 0;
+
+	if (ser->type != PORT_UNKNOWN && ser->type != PORT_NETX)
+		ret = -EINVAL;
+
+	return ret;
+}
+
+static struct uart_ops netx_pops = {
+	.tx_empty	= netx_tx_empty,
+	.set_mctrl	= netx_set_mctrl,
+	.get_mctrl	= netx_get_mctrl,
+	.stop_tx	= netx_stop_tx,
+	.start_tx	= netx_start_tx,
+	.stop_rx	= netx_stop_rx,
+	.enable_ms	= netx_enable_ms,
+	.break_ctl	= netx_break_ctl,
+	.startup	= netx_startup,
+	.shutdown	= netx_shutdown,
+	.set_termios	= netx_set_termios,
+	.type		= netx_type,
+	.release_port	= netx_release_port,
+	.request_port	= netx_request_port,
+	.config_port	= netx_config_port,
+	.verify_port	= netx_verify_port,
+};
+
+static struct netx_port netx_ports[] = {
+	{
+	.port = {
+		.type = PORT_NETX,
+		.iotype = UPIO_MEM,
+		.membase = (char __iomem *)io_p2v(NETX_PA_UART0),
+		.mapbase = NETX_PA_UART0,
+		.irq = NETX_IRQ_UART0,
+		.uartclk = 100000000,
+		.fifosize = 16,
+		.flags = UPF_BOOT_AUTOCONF,
+		.ops = &netx_pops,
+		.line = 0,
+	},
+	}, {
+	.port = {
+		.type = PORT_NETX,
+		.iotype = UPIO_MEM,
+		.membase = (char __iomem *)io_p2v(NETX_PA_UART1),
+		.mapbase = NETX_PA_UART1,
+		.irq = NETX_IRQ_UART1,
+		.uartclk = 100000000,
+		.fifosize = 16,
+		.flags = UPF_BOOT_AUTOCONF,
+		.ops = &netx_pops,
+		.line = 1,
+	},
+	}, {
+	.port = {
+		.type = PORT_NETX,
+		.iotype = UPIO_MEM,
+		.membase = (char __iomem *)io_p2v(NETX_PA_UART2),
+		.mapbase = NETX_PA_UART2,
+		.irq = NETX_IRQ_UART2,
+		.uartclk = 100000000,
+		.fifosize = 16,
+		.flags = UPF_BOOT_AUTOCONF,
+		.ops = &netx_pops,
+		.line = 2,
+	},
+	}
+};
+
+static void netx_console_putchar(struct uart_port *port, int ch)
+{
+	while (readl(port->membase + UART_FR) & FR_BUSY);
+	writel(ch, port->membase + UART_DR);
+}
+
+static void
+netx_console_write(struct console *co, const char *s, unsigned int count)
+{
+	struct uart_port *port = &netx_ports[co->index].port;
+	unsigned char cr_save;
+
+	cr_save = readl(port->membase + UART_CR);
+	writel(cr_save | CR_UART_EN, port->membase + UART_CR);
+
+	uart_console_write(port, s, count, netx_console_putchar);
+
+	while (readl(port->membase + UART_FR) & FR_BUSY);
+	writel(cr_save, port->membase + UART_CR);
+}
+
+static void __init
+netx_console_get_options(struct uart_port *port, int *baud,
+			int *parity, int *bits, int *flow)
+{
+	unsigned char line_cr;
+
+	*baud = (readl(port->membase + UART_BAUDDIV_MSB) << 8) |
+		readl(port->membase + UART_BAUDDIV_LSB);
+	*baud *= 1000;
+	*baud /= 4096;
+	*baud *= 1000;
+	*baud /= 256;
+	*baud *= 100;
+
+	line_cr = readl(port->membase + UART_LINE_CR);
+	*parity = 'n';
+	if (line_cr & LINE_CR_PEN) {
+		if (line_cr & LINE_CR_EPS)
+			*parity = 'e';
+		else
+			*parity = 'o';
+	}
+
+	switch (line_cr & LINE_CR_BITS_MASK) {
+	case LINE_CR_8BIT:
+		*bits = 8;
+		break;
+	case LINE_CR_7BIT:
+		*bits = 7;
+		break;
+	case LINE_CR_6BIT:
+		*bits = 6;
+		break;
+	case LINE_CR_5BIT:
+		*bits = 5;
+		break;
+	}
+
+	if (readl(port->membase + UART_RTS_CR) & RTS_CR_AUTO)
+		*flow = 'r';
+}
+
+static int __init
+netx_console_setup(struct console *co, char *options)
+{
+	struct netx_port *sport;
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	/*
+	 * Check whether an invalid uart number has been specified, and
+	 * if so, search for the first available port that does have
+	 * console support.
+	 */
+	if (co->index == -1 || co->index >= ARRAY_SIZE(netx_ports))
+		co->index = 0;
+	sport = &netx_ports[co->index];
+
+	if (options) {
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+	} else {
+		/* if the UART is enabled, assume it has been correctly setup
+		 * by the bootloader and get the options
+		 */
+		if (readl(sport->port.membase + UART_CR) & CR_UART_EN) {
+			netx_console_get_options(&sport->port, &baud,
+			&parity, &bits, &flow);
+		}
+
+	}
+
+	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver netx_reg;
+static struct console netx_console = {
+	.name		= "ttyNX",
+	.write		= netx_console_write,
+	.device		= uart_console_device,
+	.setup		= netx_console_setup,
+	.flags		= CON_PRINTBUFFER,
+	.index		= -1,
+	.data		= &netx_reg,
+};
+
+static int __init netx_console_init(void)
+{
+	register_console(&netx_console);
+	return 0;
+}
+console_initcall(netx_console_init);
+
+#define NETX_CONSOLE	&netx_console
+#else
+#define NETX_CONSOLE	NULL
+#endif
+
+static struct uart_driver netx_reg = {
+	.owner          = THIS_MODULE,
+	.driver_name    = DRIVER_NAME,
+	.dev_name       = "ttyNX",
+	.major          = SERIAL_NX_MAJOR,
+	.minor          = MINOR_START,
+	.nr             = ARRAY_SIZE(netx_ports),
+	.cons           = NETX_CONSOLE,
+};
+
+static int serial_netx_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct netx_port *sport = platform_get_drvdata(pdev);
+
+	if (sport)
+		uart_suspend_port(&netx_reg, &sport->port);
+
+	return 0;
+}
+
+static int serial_netx_resume(struct platform_device *pdev)
+{
+	struct netx_port *sport = platform_get_drvdata(pdev);
+
+	if (sport)
+		uart_resume_port(&netx_reg, &sport->port);
+
+	return 0;
+}
+
+static int serial_netx_probe(struct platform_device *pdev)
+{
+	struct uart_port *port = &netx_ports[pdev->id].port;
+
+	dev_info(&pdev->dev, "initialising\n");
+
+	port->dev = &pdev->dev;
+
+	writel(1, port->membase + UART_RXFIFO_IRQLEVEL);
+	uart_add_one_port(&netx_reg, &netx_ports[pdev->id].port);
+	platform_set_drvdata(pdev, &netx_ports[pdev->id]);
+
+	return 0;
+}
+
+static int serial_netx_remove(struct platform_device *pdev)
+{
+	struct netx_port *sport = platform_get_drvdata(pdev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	if (sport)
+		uart_remove_one_port(&netx_reg, &sport->port);
+
+	return 0;
+}
+
+static struct platform_driver serial_netx_driver = {
+	.probe          = serial_netx_probe,
+	.remove         = serial_netx_remove,
+
+	.suspend	= serial_netx_suspend,
+	.resume		= serial_netx_resume,
+
+	.driver		= {
+		.name   = DRIVER_NAME,
+	},
+};
+
+static int __init netx_serial_init(void)
+{
+	int ret;
+
+	printk(KERN_INFO "Serial: NetX driver\n");
+
+	ret = uart_register_driver(&netx_reg);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&serial_netx_driver);
+	if (ret != 0)
+		uart_unregister_driver(&netx_reg);
+
+	return 0;
+}
+
+static void __exit netx_serial_exit(void)
+{
+	platform_driver_unregister(&serial_netx_driver);
+	uart_unregister_driver(&netx_reg);
+}
+
+module_init(netx_serial_init);
+module_exit(netx_serial_exit);
+
+MODULE_AUTHOR("Sascha Hauer");
+MODULE_DESCRIPTION("NetX serial port driver");
+MODULE_LICENSE("GPL");