Re: [PATCH] SC26XX: New serial driver for SC2681 uarts

[tsbogend@alpha.franken.de (Thomas Bogendoerfer)]

On Mon, Dec 03, 2007 at 03:53:17PM -0800, Andrew Morton wrote:
> On Sun,  2 Dec 2007 20:43:46 +0100 (CET)
> Thomas Bogendoerfer <tsbogend@alpha.franken.de> wrote:
> 
> > New serial driver for SC2681/SC2691 uarts. Older SNI RM400 machines are
> > using these chips for onboard serial ports.
> > 
> 
> Little things...

here is an updated version.

Changes:
   - use container_of
   - remove not needed locking
   - remove inlines
   - fix macros with double argument reference

Thomas.
--

New serial driver for SC2681/SC2691 uarts. Older SNI RM400 machines are
using these chips for onboard serial ports.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
---

 drivers/serial/Kconfig  |   15 +
 drivers/serial/Makefile |    1 +
 drivers/serial/sc26xx.c |  755 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 771 insertions(+), 0 deletions(-)

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index d7e1996..2ea55d0 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -1284,4 +1284,19 @@ config SERIAL_OF_PLATFORM
 	  Currently, only 8250 compatible ports are supported, but
 	  others can easily be added.
 
+config SERIAL_SC26XX
+	tristate "SC2681/SC2692 serial port support"
+	depends on SNI_RM
+	select SERIAL_CORE
+	help
+	  This is a driver for the onboard serial ports of 
+	  older RM400 machines.
+
+config SERIAL_SC26XX_CONSOLE
+	bool "Console on SC2681/SC2692 serial port"
+	depends on SERIAL_SC26XX
+	select SERIAL_CORE_CONSOLE
+	help
+	  Support for Console on SC2681/SC2692 serial ports.
+
 endmenu
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index af6377d..87d09b6 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -64,3 +64,4 @@ obj-$(CONFIG_SERIAL_UARTLITE) += uartlite.o
 obj-$(CONFIG_SERIAL_NETX) += netx-serial.o
 obj-$(CONFIG_SERIAL_OF_PLATFORM) += of_serial.o
 obj-$(CONFIG_SERIAL_KS8695) += serial_ks8695.o
+obj-$(CONFIG_SERIAL_SC26XX) += sc26xx.o
diff --git a/drivers/serial/sc26xx.c b/drivers/serial/sc26xx.c
new file mode 100644
index 0000000..a350b6d
--- /dev/null
+++ b/drivers/serial/sc26xx.c
@@ -0,0 +1,755 @@
+/*
+ * SC268xx.c: Serial driver for Philiphs SC2681/SC2692 devices.
+ *
+ * Copyright (C) 2006,2007 Thomas Bogendörfer (tsbogend@alpha.franken.de)
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/major.h>
+#include <linux/circ_buf.h>
+#include <linux/serial.h>
+#include <linux/sysrq.h>
+#include <linux/console.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/irq.h>
+
+#if defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+
+#define SC26XX_MAJOR         204
+#define SC26XX_MINOR_START   205
+#define SC26XX_NR            2
+
+struct uart_sc26xx_port {
+	struct uart_port      port[2];
+	u8     dsr_mask[2];
+	u8     cts_mask[2];
+	u8     dcd_mask[2];
+	u8     ri_mask[2];
+	u8     dtr_mask[2];
+	u8     rts_mask[2];
+	u8     imr;
+};
+
+/* register common to both ports */
+#define RD_ISR      0x14
+#define RD_IPR      0x34
+
+#define WR_ACR      0x10
+#define WR_IMR      0x14
+#define WR_OPCR     0x34
+#define WR_OPR_SET  0x38
+#define WR_OPR_CLR  0x3C
+
+/* access common register */
+#define READ_SC(p, r)        readb((p)->membase + RD_##r)
+#define WRITE_SC(p, r, v)    writeb((v), (p)->membase + WR_##r)
+
+/* register per port */
+#define RD_PORT_MRx 0x00
+#define RD_PORT_SR  0x04
+#define RD_PORT_RHR 0x0c
+
+#define WR_PORT_MRx 0x00
+#define WR_PORT_CSR 0x04
+#define WR_PORT_CR  0x08
+#define WR_PORT_THR 0x0c
+
+/* SR bits */
+#define SR_BREAK    (1 << 7)
+#define SR_FRAME    (1 << 6)
+#define SR_PARITY   (1 << 5)
+#define SR_OVERRUN  (1 << 4)
+#define SR_TXRDY    (1 << 2)
+#define SR_RXRDY    (1 << 0)
+
+#define CR_RES_MR   (1 << 4)
+#define CR_RES_RX   (2 << 4)
+#define CR_RES_TX   (3 << 4)
+#define CR_STRT_BRK (6 << 4)
+#define CR_STOP_BRK (7 << 4)
+#define CR_DIS_TX   (1 << 3)
+#define CR_ENA_TX   (1 << 2)
+#define CR_DIS_RX   (1 << 1)
+#define CR_ENA_RX   (1 << 0)
+
+/* ISR bits */
+#define ISR_RXRDYB  (1 << 5)
+#define ISR_TXRDYB  (1 << 4)
+#define ISR_RXRDYA  (1 << 1)
+#define ISR_TXRDYA  (1 << 0)
+
+/* IMR bits */
+#define IMR_RXRDY   (1 << 1)
+#define IMR_TXRDY   (1 << 0)
+
+/* access port register */
+static inline u8 read_sc_port(struct uart_port *p, u8 reg)
+{
+	return readb(p->membase + p->line * 0x20 + reg);
+}
+
+static inline void write_sc_port(struct uart_port *p, u8 reg, u8 val)
+{
+	writeb(val, p->membase + p->line * 0x20 + reg);
+}
+
+#define READ_SC_PORT(p, r)     read_sc_port(p, RD_PORT_##r)
+#define WRITE_SC_PORT(p, r, v) write_sc_port(p, WR_PORT_##r, v)
+
+static void sc26xx_enable_irq(struct uart_port *port, int mask)
+{
+	struct uart_sc26xx_port *up;
+	int line = port->line;
+
+	port -= line;
+	up = container_of(port, struct uart_sc26xx_port, port[0]);
+
+	up->imr |= mask << (line * 4);
+	WRITE_SC(port, IMR, up->imr);
+}
+
+static void sc26xx_disable_irq(struct uart_port *port, int mask)
+{
+	struct uart_sc26xx_port *up;
+	int line = port->line;
+
+	port -= line;
+	up = container_of(port, struct uart_sc26xx_port, port[0]);
+
+	up->imr &= ~(mask << (line * 4));
+	WRITE_SC(port, IMR, up->imr);
+}
+
+static struct tty_struct *receive_chars(struct uart_port *port)
+{
+	struct tty_struct *tty = NULL;
+	int limit = 10000;
+	unsigned char ch;
+	char flag;
+	u8 status;
+
+	if (port->info != NULL)		/* Unopened serial console */
+		tty = port->info->tty;
+
+	while (limit-- > 0) {
+		status = READ_SC_PORT(port, SR);
+		if (!(status & SR_RXRDY))
+			break;
+		ch = READ_SC_PORT(port, RHR);
+
+		flag = TTY_NORMAL;
+		port->icount.rx++;
+
+		if (unlikely(status & (SR_BREAK | SR_FRAME |
+				       SR_PARITY | SR_OVERRUN))) {
+			if (status & SR_BREAK) {
+				status &= ~(SR_PARITY | SR_FRAME);
+				port->icount.brk++;
+				if (uart_handle_break(port))
+					continue;
+			} else if (status & SR_PARITY)
+				port->icount.parity++;
+			else if (status & SR_FRAME)
+				port->icount.frame++;
+			if (status & SR_OVERRUN)
+				port->icount.overrun++;
+
+			status &= port->read_status_mask;
+			if (status & SR_BREAK)
+				flag = TTY_BREAK;
+			else if (status & SR_PARITY)
+				flag = TTY_PARITY;
+			else if (status & SR_FRAME)
+				flag = TTY_FRAME;
+		}
+
+		if (uart_handle_sysrq_char(port, ch))
+			continue;
+
+		if (status & port->ignore_status_mask)
+			continue;
+
+		tty_insert_flip_char(tty, ch, flag);
+	}
+	return tty;
+}
+
+static void transmit_chars(struct uart_port *port)
+{
+	struct circ_buf *xmit;
+
+	if (!port->info)
+		return;
+
+	xmit = &port->info->xmit;
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+		sc26xx_disable_irq(port, IMR_TXRDY);
+		return;
+	}
+	while (!uart_circ_empty(xmit)) {
+		if (!(READ_SC_PORT(port, SR) & SR_TXRDY))
+			break;
+
+		WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+	}
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+}
+
+static irqreturn_t sc26xx_interrupt(int irq, void *dev_id)
+{
+	struct uart_sc26xx_port *up = dev_id;
+	struct tty_struct *tty;
+	unsigned long flags;
+	u8 isr;
+
+	spin_lock_irqsave(&up->port[0].lock, flags);
+
+	tty = NULL;
+	isr = READ_SC(&up->port[0], ISR);
+	if (isr & ISR_TXRDYA)
+	    transmit_chars(&up->port[0]);
+	if (isr & ISR_RXRDYA)
+	    tty = receive_chars(&up->port[0]);
+
+	spin_unlock(&up->port[0].lock);
+
+	if (tty)
+		tty_flip_buffer_push(tty);
+
+	spin_lock(&up->port[1].lock);
+
+	tty = NULL;
+	if (isr & ISR_TXRDYB)
+	    transmit_chars(&up->port[1]);
+	if (isr & ISR_RXRDYB)
+	    tty = receive_chars(&up->port[1]);
+
+	spin_unlock_irqrestore(&up->port[1].lock, flags);
+
+	if (tty)
+		tty_flip_buffer_push(tty);
+
+	return IRQ_HANDLED;
+}
+
+/* port->lock is not held.  */
+static unsigned int sc26xx_tx_empty(struct uart_port *port)
+{
+	return (READ_SC_PORT(port, SR) & SR_TXRDY) ? TIOCSER_TEMT : 0;
+}
+
+/* port->lock held by caller.  */
+static void sc26xx_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	struct uart_sc26xx_port *up;
+	int line = port->line;
+
+	port -= line;
+	up = container_of(port, struct uart_sc26xx_port, port[0]);
+
+	if (up->dtr_mask[line]) {
+		if (mctrl & TIOCM_DTR)
+			WRITE_SC(port, OPR_SET, up->dtr_mask[line]);
+		else
+			WRITE_SC(port, OPR_CLR, up->dtr_mask[line]);
+	}
+	if (up->rts_mask[line]) {
+		if (mctrl & TIOCM_RTS)
+			WRITE_SC(port, OPR_SET, up->rts_mask[line]);
+		else
+			WRITE_SC(port, OPR_CLR, up->rts_mask[line]);
+	}
+}
+
+/* port->lock is held by caller and interrupts are disabled.  */
+static unsigned int sc26xx_get_mctrl(struct uart_port *port)
+{
+	struct uart_sc26xx_port *up;
+	int line = port->line;
+	unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
+	u8 ipr;
+
+	port -= line;
+	up = container_of(port, struct uart_sc26xx_port, port[0]);
+	ipr = READ_SC(port, IPR) ^ 0xff;
+
+	if (up->dsr_mask[line]) {
+		mctrl &= ~TIOCM_DSR;
+		mctrl |= ipr & up->dsr_mask[line] ? TIOCM_DSR : 0;
+	}
+	if (up->cts_mask[line]) {
+		mctrl &= ~TIOCM_CTS;
+		mctrl |= ipr & up->cts_mask[line] ? TIOCM_CTS : 0;
+	}
+	if (up->dcd_mask[line]) {
+		mctrl &= ~TIOCM_CAR;
+		mctrl |= ipr & up->dcd_mask[line] ? TIOCM_CAR : 0;
+	}
+	if (up->ri_mask[line]) {
+		mctrl &= ~TIOCM_RNG;
+		mctrl |= ipr & up->ri_mask[line] ? TIOCM_RNG : 0;
+	}
+	return mctrl;
+}
+
+/* port->lock held by caller.  */
+static void sc26xx_stop_tx(struct uart_port *port)
+{
+	return;
+}
+
+/* port->lock held by caller.  */
+static void sc26xx_start_tx(struct uart_port *port)
+{
+	struct circ_buf *xmit = &port->info->xmit;
+
+	while (!uart_circ_empty(xmit)) {
+		if (!(READ_SC_PORT(port, SR) & SR_TXRDY)) {
+			sc26xx_enable_irq(port, IMR_TXRDY);
+			break;
+		}
+		WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+	}
+}
+
+/* port->lock held by caller.  */
+static void sc26xx_stop_rx(struct uart_port *port)
+{
+}
+
+/* port->lock held by caller.  */
+static void sc26xx_enable_ms(struct uart_port *port)
+{
+}
+
+/* port->lock is not held.  */
+static void sc26xx_break_ctl(struct uart_port *port, int break_state)
+{
+	if (break_state == -1)
+		WRITE_SC_PORT(port, CR, CR_STRT_BRK);
+	else
+		WRITE_SC_PORT(port, CR, CR_STOP_BRK);
+}
+
+/* port->lock is not held.  */
+static int sc26xx_startup(struct uart_port *port)
+{
+	sc26xx_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
+	WRITE_SC(port, OPCR, 0);
+
+	/* reset tx and rx */
+	WRITE_SC_PORT(port, CR, CR_RES_RX);
+	WRITE_SC_PORT(port, CR, CR_RES_TX);
+
+	/* start rx/tx */
+	WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX);
+
+	/* enable irqs */
+	sc26xx_enable_irq(port, IMR_RXRDY);
+	return 0;
+}
+
+/* port->lock is not held.  */
+static void sc26xx_shutdown(struct uart_port *port)
+{
+	/* disable interrupst */
+	sc26xx_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
+
+	/* stop tx/rx */
+	WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX);
+}
+
+/* port->lock is not held.  */
+static void sc26xx_set_termios(struct uart_port *port, struct ktermios *termios,
+			      struct ktermios *old)
+{
+	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
+	unsigned int quot = uart_get_divisor(port, baud);
+	unsigned int iflag, cflag;
+	unsigned long flags;
+	u8 mr1, mr2, csr;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc)
+		udelay(2);
+
+	WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX);
+
+	iflag = termios->c_iflag;
+	cflag = termios->c_cflag;
+
+	port->read_status_mask = SR_OVERRUN;
+	if (iflag & INPCK)
+		port->read_status_mask |= SR_PARITY | SR_FRAME;
+	if (iflag & (BRKINT | PARMRK))
+		port->read_status_mask |= SR_BREAK;
+
+	port->ignore_status_mask = 0;
+	if (iflag & IGNBRK)
+		port->ignore_status_mask |= SR_BREAK;
+	if ((cflag & CREAD) == 0)
+		port->ignore_status_mask |= SR_BREAK | SR_FRAME |
+					    SR_PARITY | SR_OVERRUN;
+
+	switch (cflag & CSIZE) {
+	case CS5:
+		mr1 = 0x00;
+		break;
+	case CS6:
+		mr1 = 0x01;
+		break;
+	case CS7:
+		mr1 = 0x02;
+		break;
+	default:
+	case CS8:
+		mr1 = 0x03;
+		break;
+	}
+	mr2 = 0x07;
+	if (cflag & CSTOPB)
+		mr2 = 0x0f;
+	if (cflag & PARENB) {
+		if (cflag & PARODD)
+			mr1 |= (1 << 2);
+	} else
+		mr1 |= (2 << 3);
+
+	switch (baud) {
+	case 50:
+		csr = 0x00;
+		break;
+	case 110:
+		csr = 0x11;
+		break;
+	case 134:
+		csr = 0x22;
+		break;
+	case 200:
+		csr = 0x33;
+		break;
+	case 300:
+		csr = 0x44;
+		break;
+	case 600:
+		csr = 0x55;
+		break;
+	case 1200:
+		csr = 0x66;
+		break;
+	case 2400:
+		csr = 0x88;
+		break;
+	case 4800:
+		csr = 0x99;
+		break;
+	default:
+	case 9600:
+		csr = 0xbb;
+		break;
+	case 19200:
+		csr = 0xcc;
+		break;
+	}
+
+	WRITE_SC_PORT(port, CR, CR_RES_MR);
+	WRITE_SC_PORT(port, MRx, mr1);
+	WRITE_SC_PORT(port, MRx, mr2);
+
+	WRITE_SC(port, ACR, 0x80);
+	WRITE_SC_PORT(port, CSR, csr);
+
+	/* reset tx and rx */
+	WRITE_SC_PORT(port, CR, CR_RES_RX);
+	WRITE_SC_PORT(port, CR, CR_RES_TX);
+
+	WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX);
+	while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc)
+		udelay(2);
+
+	/* XXX */
+	uart_update_timeout(port, cflag,
+			    (port->uartclk / (16 * quot)));
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *sc26xx_type(struct uart_port *port)
+{
+	return "SC26XX";
+}
+
+static void sc26xx_release_port(struct uart_port *port)
+{
+}
+
+static int sc26xx_request_port(struct uart_port *port)
+{
+	return 0;
+}
+
+static void sc26xx_config_port(struct uart_port *port, int flags)
+{
+}
+
+static int sc26xx_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+	return -EINVAL;
+}
+
+static struct uart_ops sc26xx_ops = {
+	.tx_empty	= sc26xx_tx_empty,
+	.set_mctrl	= sc26xx_set_mctrl,
+	.get_mctrl	= sc26xx_get_mctrl,
+	.stop_tx	= sc26xx_stop_tx,
+	.start_tx	= sc26xx_start_tx,
+	.stop_rx	= sc26xx_stop_rx,
+	.enable_ms	= sc26xx_enable_ms,
+	.break_ctl	= sc26xx_break_ctl,
+	.startup	= sc26xx_startup,
+	.shutdown	= sc26xx_shutdown,
+	.set_termios	= sc26xx_set_termios,
+	.type		= sc26xx_type,
+	.release_port	= sc26xx_release_port,
+	.request_port	= sc26xx_request_port,
+	.config_port	= sc26xx_config_port,
+	.verify_port	= sc26xx_verify_port,
+};
+
+static struct uart_port *sc26xx_port;
+
+#ifdef CONFIG_SERIAL_SC26XX_CONSOLE
+static void sc26xx_console_putchar(struct uart_port *port, char c)
+{
+	unsigned long flags;
+	int limit = 1000000;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	while (limit-- > 0) {
+		if (READ_SC_PORT(port, SR) & SR_TXRDY) {
+			WRITE_SC_PORT(port, THR, c);
+			break;
+		}
+		udelay(2);
+	}
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void sc26xx_console_write(struct console *con, const char *s, unsigned n)
+{
+	struct uart_port *port = sc26xx_port;
+	int i;
+
+	for (i = 0; i < n; i++) {
+		if (*s == '\n')
+			sc26xx_console_putchar(port, '\r');
+		sc26xx_console_putchar(port, *s++);
+	}
+}
+
+static int __init sc26xx_console_setup(struct console *con, char *options)
+{
+	struct uart_port *port = sc26xx_port;
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	if (port->type != PORT_SC26XX)
+		return -1;
+
+	printk(KERN_INFO "Console: ttySC%d (SC26XX)\n", con->index);
+	if (options)
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+	return uart_set_options(port, con, baud, parity, bits, flow);
+}
+
+static struct uart_driver sc26xx_reg;
+static struct console sc26xx_console = {
+	.name	=	"ttySC",
+	.write	=	sc26xx_console_write,
+	.device	=	uart_console_device,
+	.setup  =       sc26xx_console_setup,
+	.flags	=	CON_PRINTBUFFER,
+	.index	=	-1,
+	.data	=	&sc26xx_reg,
+};
+#define SC26XX_CONSOLE   &sc26xx_console
+#else
+#define SC26XX_CONSOLE   NULL
+#endif
+
+static struct uart_driver sc26xx_reg = {
+	.owner			= THIS_MODULE,
+	.driver_name		= "SC26xx",
+	.dev_name		= "ttySC",
+	.major			= SC26XX_MAJOR,
+	.minor			= SC26XX_MINOR_START,
+	.nr			= SC26XX_NR,
+	.cons                   = SC26XX_CONSOLE,
+};
+
+static u8 sc26xx_flags2mask(unsigned int flags, unsigned int bitpos)
+{
+	unsigned int bit = (flags >> bitpos) & 15;
+
+	return bit ? (1 << (bit - 1)) : 0;
+}
+
+static void __devinit sc26xx_init_masks(struct uart_sc26xx_port *up,
+					int line, unsigned int data)
+{
+	up->dtr_mask[line] = sc26xx_flags2mask(data,  0);
+	up->rts_mask[line] = sc26xx_flags2mask(data,  4);
+	up->dsr_mask[line] = sc26xx_flags2mask(data,  8);
+	up->cts_mask[line] = sc26xx_flags2mask(data, 12);
+	up->dcd_mask[line] = sc26xx_flags2mask(data, 16);
+	up->ri_mask[line]  = sc26xx_flags2mask(data, 20);
+}
+
+static int __devinit sc26xx_probe(struct platform_device *dev)
+{
+	struct resource *res;
+	struct uart_sc26xx_port *up;
+	unsigned int *sc26xx_data = dev->dev.platform_data;
+	int err;
+
+	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	up = kzalloc(sizeof *up, GFP_KERNEL);
+	if (unlikely(!up))
+		return -ENOMEM;
+
+	up->port[0].line = 0;
+	up->port[0].ops = &sc26xx_ops;
+	up->port[0].type = PORT_SC26XX;
+	up->port[0].uartclk = (29491200 / 16); /* arbitrary */
+
+	up->port[0].mapbase = res->start;
+	up->port[0].membase = ioremap_nocache(up->port[0].mapbase, 0x40);
+	up->port[0].iotype = UPIO_MEM;
+	up->port[0].irq = platform_get_irq(dev, 0);
+
+	up->port[0].dev = &dev->dev;
+
+	sc26xx_init_masks(up, 0, sc26xx_data[0]);
+
+	sc26xx_port = &up->port[0];
+
+	up->port[1].line = 1;
+	up->port[1].ops = &sc26xx_ops;
+	up->port[1].type = PORT_SC26XX;
+	up->port[1].uartclk = (29491200 / 16); /* arbitrary */
+
+	up->port[1].mapbase = up->port[0].mapbase;
+	up->port[1].membase = up->port[0].membase;
+	up->port[1].iotype = UPIO_MEM;
+	up->port[1].irq = up->port[0].irq;
+
+	up->port[1].dev = &dev->dev;
+
+	sc26xx_init_masks(up, 1, sc26xx_data[1]);
+
+	err = uart_register_driver(&sc26xx_reg);
+	if (err)
+		goto out_free_port;
+
+	sc26xx_reg.tty_driver->name_base = sc26xx_reg.minor;
+
+	err = uart_add_one_port(&sc26xx_reg, &up->port[0]);
+	if (err)
+		goto out_unregister_driver;
+
+	err = uart_add_one_port(&sc26xx_reg, &up->port[1]);
+	if (err)
+		goto out_remove_port0;
+
+	err = request_irq(up->port[0].irq, sc26xx_interrupt, 0, "sc26xx", up);
+	if (err)
+		goto out_remove_ports;
+
+	dev_set_drvdata(&dev->dev, up);
+	return 0;
+
+out_remove_ports:
+	uart_remove_one_port(&sc26xx_reg, &up->port[1]);
+out_remove_port0:
+	uart_remove_one_port(&sc26xx_reg, &up->port[0]);
+
+out_unregister_driver:
+	uart_unregister_driver(&sc26xx_reg);
+
+out_free_port:
+	kfree(up);
+	sc26xx_port = NULL;
+	return err;
+}
+
+
+static int __exit sc26xx_driver_remove(struct platform_device *dev)
+{
+	struct uart_sc26xx_port *up = dev_get_drvdata(&dev->dev);
+
+	free_irq(up->port[0].irq, up);
+
+	uart_remove_one_port(&sc26xx_reg, &up->port[0]);
+	uart_remove_one_port(&sc26xx_reg, &up->port[1]);
+
+	uart_unregister_driver(&sc26xx_reg);
+
+	kfree(up);
+	sc26xx_port = NULL;
+
+	dev_set_drvdata(&dev->dev, NULL);
+	return 0;
+}
+
+static struct platform_driver sc26xx_driver = {
+	.probe	= sc26xx_probe,
+	.remove	= __devexit_p(sc26xx_driver_remove),
+	.driver	= {
+		.name	= "SC26xx",
+	},
+};
+
+static int __init sc26xx_init(void)
+{
+	return platform_driver_register(&sc26xx_driver);
+}
+
+static void __exit sc26xx_exit(void)
+{
+	platform_driver_unregister(&sc26xx_driver);
+}
+
+module_init(sc26xx_init);
+module_exit(sc26xx_exit);
+
+
+MODULE_AUTHOR("Thomas Bogendörfer");
+MODULE_DESCRIPTION("SC681/SC2692 serial driver");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL");