]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
SC26XX: New serial driver for SC2681 uarts
authorThomas Bogendoerfer <tsbogend@alpha.franken.de>
Wed, 6 Feb 2008 09:37:27 +0000 (01:37 -0800)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Wed, 6 Feb 2008 18:41:06 +0000 (10:41 -0800)
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>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Torben Mathiasen <device@lanana.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/serial/Kconfig
drivers/serial/Makefile
drivers/serial/sc26xx.c [new file with mode: 0644]

index 43fbba4a57e6d4769534013afceb95ee24dcb591..6a44fb1dc167c0c74a39ac161f287e68c64e212f 100644 (file)
@@ -1318,4 +1318,19 @@ config SERIAL_QE
          This driver supports the QE serial ports on Freescale embedded
          PowerPC that contain a QUICC Engine.
 
+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
index 2dd41b4cc8dbf1cc930b852a8d4c0fea67d94db0..640cfe44a56dd309cacc16efa2c86378af5048c2 100644 (file)
@@ -55,6 +55,7 @@ obj-$(CONFIG_SERIAL_M32R_SIO) += m32r_sio.o
 obj-$(CONFIG_SERIAL_MPSC) += mpsc.o
 obj-$(CONFIG_SERIAL_SB1250_DUART) += sb1250-duart.o
 obj-$(CONFIG_ETRAX_SERIAL) += crisv10.o
+obj-$(CONFIG_SERIAL_SC26XX) += sc26xx.o
 obj-$(CONFIG_SERIAL_JSM) += jsm/
 obj-$(CONFIG_SERIAL_TXX9) += serial_txx9.o
 obj-$(CONFIG_SERIAL_VR41XX) += vr41xx_siu.o
diff --git a/drivers/serial/sc26xx.c b/drivers/serial/sc26xx.c
new file mode 100644 (file)
index 0000000..a350b6d
--- /dev/null
@@ -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");