[PATCH] PNX8550 UART driver

Add UART support for PNX8330/8550/8950 Philips MIPS-based SoCs.

Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 869 insertions, 0 deletions

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index d0edbaacb1f7..e8dd71df9165 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -686,6 +686,22 @@ config SERIAL_SH_SCI_CONSOLE
         depends on SERIAL_SH_SCI=y
         select SERIAL_CORE_CONSOLE
 
+config SERIAL_PNX8XXX
+        bool "Enable PNX8XXX SoCs' UART Support"
+        depends on MIPS && SOC_PNX8550
+        select SERIAL_CORE
+        help
+          If you have a MIPS-based Philips SoC such as PNX8550 or PNX8330
+          and you want to use serial ports, say Y.  Otherwise, say N.
+
+config SERIAL_PNX8XXX_CONSOLE
+        bool "Enable PNX8XX0 serial console"
+        depends on SERIAL_PNX8XXX
+        select SERIAL_CORE_CONSOLE
+        help
+          If you have a MIPS-based Philips SoC such as PNX8550 or PNX8330
+          and you want to use serial console, say Y. Otherwise, say N.
+
 config SERIAL_CORE
         tristate
 
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index f3f82587b5fa..6b3560c5749a 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_SERIAL_AMBA_PL010) += amba-pl010.o
 obj-$(CONFIG_SERIAL_AMBA_PL011) += amba-pl011.o
 obj-$(CONFIG_SERIAL_CLPS711X) += clps711x.o
 obj-$(CONFIG_SERIAL_PXA) += pxa.o
+obj-$(CONFIG_SERIAL_PNX8XXX) += pnx8xxx_uart.o
 obj-$(CONFIG_SERIAL_SA1100) += sa1100.o
 obj-$(CONFIG_SERIAL_S3C2410) += s3c2410.o
 obj-$(CONFIG_SERIAL_SUNCORE) += suncore.o
diff --git a/drivers/serial/pnx8xxx_uart.c b/drivers/serial/pnx8xxx_uart.c
new file mode 100644
index 000000000000..8d01c59e8d04
--- /dev/null
+++ b/drivers/serial/pnx8xxx_uart.c
@@ -0,0 +1,852 @@
+/*
+ * UART driver for PNX8XXX SoCs
+ *
+ * Author: Per Hallsmark per.hallsmark@mvista.com
+ * Ported to 2.6 kernel by EmbeddedAlley
+ * Reworked by Vitaly Wool <vitalywool@gmail.com>
+ *
+ * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ * Copyright (C) 2000 Deep Blue Solutions Ltd.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of
+ * any kind, whether express or implied.
+ *
+ */
+
+#if defined(CONFIG_SERIAL_PNX8XXX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/device.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 <linux/serial_pnx8xxx.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+/* We'll be using StrongARM sa1100 serial port major/minor */
+#define SERIAL_PNX8XXX_MAJOR    204
+#define MINOR_START             5
+
+#define NR_PORTS                2
+
+#define PNX8XXX_ISR_PASS_LIMIT  256
+
+/*
+ * Convert from ignore_status_mask or read_status_mask to FIFO
+ * and interrupt status bits
+ */
+#define SM_TO_FIFO(x)   ((x) >> 10)
+#define SM_TO_ISTAT(x)  ((x) & 0x000001ff)
+#define FIFO_TO_SM(x)   ((x) << 10)
+#define ISTAT_TO_SM(x)  ((x) & 0x000001ff)
+
+/*
+ * This is the size of our serial port register set.
+ */
+#define UART_PORT_SIZE  0x1000
+
+/*
+ * This determines how often we check the modem status signals
+ * for any change.  They generally aren't connected to an IRQ
+ * so we have to poll them.  We also check immediately before
+ * filling the TX fifo incase CTS has been dropped.
+ */
+#define MCTRL_TIMEOUT   (250*HZ/1000)
+
+extern struct pnx8xxx_port pnx8xxx_ports[];
+
+static inline int serial_in(struct pnx8xxx_port *sport, int offset)
+{
+        return (__raw_readl(sport->port.membase + offset));
+}
+
+static inline void serial_out(struct pnx8xxx_port *sport, int offset, int value)
+{
+        __raw_writel(value, sport->port.membase + offset);
+}
+
+/*
+ * Handle any change of modem status signal since we were last called.
+ */
+static void pnx8xxx_mctrl_check(struct pnx8xxx_port *sport)
+{
+        unsigned int status, changed;
+
+        status = sport->port.ops->get_mctrl(&sport->port);
+        changed = status ^ sport->old_status;
+
+        if (changed == 0)
+                return;
+
+        sport->old_status = status;
+
+        if (changed & TIOCM_RI)
+                sport->port.icount.rng++;
+        if (changed & TIOCM_DSR)
+                sport->port.icount.dsr++;
+        if (changed & TIOCM_CAR)
+                uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
+        if (changed & TIOCM_CTS)
+                uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
+
+        wake_up_interruptible(&sport->port.info->delta_msr_wait);
+}
+
+/*
+ * This is our per-port timeout handler, for checking the
+ * modem status signals.
+ */
+static void pnx8xxx_timeout(unsigned long data)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)data;
+        unsigned long flags;
+
+        if (sport->port.info) {
+                spin_lock_irqsave(&sport->port.lock, flags);
+                pnx8xxx_mctrl_check(sport);
+                spin_unlock_irqrestore(&sport->port.lock, flags);
+
+                mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
+        }
+}
+
+/*
+ * interrupts disabled on entry
+ */
+static void pnx8xxx_stop_tx(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        u32 ien;
+
+        /* Disable TX intr */
+        ien = serial_in(sport, PNX8XXX_IEN);
+        serial_out(sport, PNX8XXX_IEN, ien & ~PNX8XXX_UART_INT_ALLTX);
+
+        /* Clear all pending TX intr */
+        serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLTX);
+}
+
+/*
+ * interrupts may not be disabled on entry
+ */
+static void pnx8xxx_start_tx(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        u32 ien;
+
+        /* Clear all pending TX intr */
+        serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLTX);
+
+        /* Enable TX intr */
+        ien = serial_in(sport, PNX8XXX_IEN);
+        serial_out(sport, PNX8XXX_IEN, ien | PNX8XXX_UART_INT_ALLTX);
+}
+
+/*
+ * Interrupts enabled
+ */
+static void pnx8xxx_stop_rx(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        u32 ien;
+
+        /* Disable RX intr */
+        ien = serial_in(sport, PNX8XXX_IEN);
+        serial_out(sport, PNX8XXX_IEN, ien & ~PNX8XXX_UART_INT_ALLRX);
+
+        /* Clear all pending RX intr */
+        serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX);
+}
+
+/*
+ * Set the modem control timer to fire immediately.
+ */
+static void pnx8xxx_enable_ms(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+
+        mod_timer(&sport->timer, jiffies);
+}
+
+static void pnx8xxx_rx_chars(struct pnx8xxx_port *sport)
+{
+        struct tty_struct *tty = sport->port.info->tty;
+        unsigned int status, ch, flg;
+
+        status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
+                 ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
+        while (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFIFO)) {
+                ch = serial_in(sport, PNX8XXX_FIFO);
+
+                sport->port.icount.rx++;
+
+                flg = TTY_NORMAL;
+
+                /*
+                 * note that the error handling code is
+                 * out of the main execution path
+                 */
+                if (status & (FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE |
+                                        PNX8XXX_UART_FIFO_RXPAR) |
+                              ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN))) {
+                        if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR))
+                                sport->port.icount.parity++;
+                        else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE))
+                                sport->port.icount.frame++;
+                        if (status & ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN))
+                                sport->port.icount.overrun++;
+
+                        status &= sport->port.read_status_mask;
+
+                        if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR))
+                                flg = TTY_PARITY;
+                        else if (status & FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE))
+                                flg = TTY_FRAME;
+
+#ifdef SUPPORT_SYSRQ
+                        sport->port.sysrq = 0;
+#endif
+                }
+
+                if (uart_handle_sysrq_char(&sport->port, ch))
+                        goto ignore_char;
+
+                uart_insert_char(&sport->port, status,
+                                ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN), ch, flg);
+
+        ignore_char:
+                serial_out(sport, PNX8XXX_LCR, serial_in(sport, PNX8XXX_LCR) |
+                                PNX8XXX_UART_LCR_RX_NEXT);
+                status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
+                         ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
+        }
+        tty_flip_buffer_push(tty);
+}
+
+static void pnx8xxx_tx_chars(struct pnx8xxx_port *sport)
+{
+        struct circ_buf *xmit = &sport->port.info->xmit;
+
+        if (sport->port.x_char) {
+                serial_out(sport, PNX8XXX_FIFO, sport->port.x_char);
+                sport->port.icount.tx++;
+                sport->port.x_char = 0;
+                return;
+        }
+
+        /*
+         * Check the modem control lines before
+         * transmitting anything.
+         */
+        pnx8xxx_mctrl_check(sport);
+
+        if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
+                pnx8xxx_stop_tx(&sport->port);
+                return;
+        }
+
+        /*
+         * TX while bytes available
+         */
+        while (((serial_in(sport, PNX8XXX_FIFO) &
+                                        PNX8XXX_UART_FIFO_TXFIFO) >> 16) < 16) {
+                serial_out(sport, PNX8XXX_FIFO, xmit->buf[xmit->tail]);
+                xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+                sport->port.icount.tx++;
+                if (uart_circ_empty(xmit))
+                        break;
+        }
+
+        if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+                uart_write_wakeup(&sport->port);
+
+        if (uart_circ_empty(xmit))
+                pnx8xxx_stop_tx(&sport->port);
+}
+
+static irqreturn_t pnx8xxx_int(int irq, void *dev_id)
+{
+        struct pnx8xxx_port *sport = dev_id;
+        unsigned int status;
+
+        spin_lock(&sport->port.lock);
+        /* Get the interrupts */
+        status  = serial_in(sport, PNX8XXX_ISTAT) & serial_in(sport, PNX8XXX_IEN);
+
+        /* Break signal received */
+        if (status & PNX8XXX_UART_INT_BREAK) {
+                sport->port.icount.brk++;
+                uart_handle_break(&sport->port);
+        }
+
+        /* Byte received */
+        if (status & PNX8XXX_UART_INT_RX)
+                pnx8xxx_rx_chars(sport);
+
+        /* TX holding register empty - transmit a byte */
+        if (status & PNX8XXX_UART_INT_TX)
+                pnx8xxx_tx_chars(sport);
+
+        /* Clear the ISTAT register */
+        serial_out(sport, PNX8XXX_ICLR, status);
+
+        spin_unlock(&sport->port.lock);
+        return IRQ_HANDLED;
+}
+
+/*
+ * Return TIOCSER_TEMT when transmitter is not busy.
+ */
+static unsigned int pnx8xxx_tx_empty(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+
+        return serial_in(sport, PNX8XXX_FIFO) & PNX8XXX_UART_FIFO_TXFIFO_STA ? 0 : TIOCSER_TEMT;
+}
+
+static unsigned int pnx8xxx_get_mctrl(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        unsigned int mctrl = TIOCM_DSR;
+        unsigned int msr;
+
+        /* REVISIT */
+
+        msr = serial_in(sport, PNX8XXX_MCR);
+
+        mctrl |= msr & PNX8XXX_UART_MCR_CTS ? TIOCM_CTS : 0;
+        mctrl |= msr & PNX8XXX_UART_MCR_DCD ? TIOCM_CAR : 0;
+
+        return mctrl;
+}
+
+static void pnx8xxx_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+#if     0       /* FIXME */
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        unsigned int msr;
+#endif
+}
+
+/*
+ * Interrupts always disabled.
+ */
+static void pnx8xxx_break_ctl(struct uart_port *port, int break_state)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        unsigned long flags;
+        unsigned int lcr;
+
+        spin_lock_irqsave(&sport->port.lock, flags);
+        lcr = serial_in(sport, PNX8XXX_LCR);
+        if (break_state == -1)
+                lcr |= PNX8XXX_UART_LCR_TXBREAK;
+        else
+                lcr &= ~PNX8XXX_UART_LCR_TXBREAK;
+        serial_out(sport, PNX8XXX_LCR, lcr);
+        spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+static int pnx8xxx_startup(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        int retval;
+
+        /*
+         * Allocate the IRQ
+         */
+        retval = request_irq(sport->port.irq, pnx8xxx_int, 0,
+                             "pnx8xxx-uart", sport);
+        if (retval)
+                return retval;
+
+        /*
+         * Finally, clear and enable interrupts
+         */
+
+        serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX |
+                             PNX8XXX_UART_INT_ALLTX);
+
+        serial_out(sport, PNX8XXX_IEN, serial_in(sport, PNX8XXX_IEN) |
+                            PNX8XXX_UART_INT_ALLRX |
+                            PNX8XXX_UART_INT_ALLTX);
+
+        /*
+         * Enable modem status interrupts
+         */
+        spin_lock_irq(&sport->port.lock);
+        pnx8xxx_enable_ms(&sport->port);
+        spin_unlock_irq(&sport->port.lock);
+
+        return 0;
+}
+
+static void pnx8xxx_shutdown(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        int lcr;
+
+        /*
+         * Stop our timer.
+         */
+        del_timer_sync(&sport->timer);
+
+        /*
+         * Disable all interrupts
+         */
+        serial_out(sport, PNX8XXX_IEN, 0);
+
+        /*
+         * Reset the Tx and Rx FIFOS, disable the break condition
+         */
+        lcr = serial_in(sport, PNX8XXX_LCR);
+        lcr &= ~PNX8XXX_UART_LCR_TXBREAK;
+        lcr |= PNX8XXX_UART_LCR_TX_RST | PNX8XXX_UART_LCR_RX_RST;
+        serial_out(sport, PNX8XXX_LCR, lcr);
+
+        /*
+         * Clear all interrupts
+         */
+        serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_ALLRX |
+                             PNX8XXX_UART_INT_ALLTX);
+
+        /*
+         * Free the interrupt
+         */
+        free_irq(sport->port.irq, sport);
+}
+
+static void
+pnx8xxx_set_termios(struct uart_port *port, struct ktermios *termios,
+                   struct ktermios *old)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        unsigned long flags;
+        unsigned int lcr_fcr, old_ien, baud, quot;
+        unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
+
+        /*
+         * We only support CS7 and CS8.
+         */
+        while ((termios->c_cflag & CSIZE) != CS7 &&
+               (termios->c_cflag & CSIZE) != CS8) {
+                termios->c_cflag &= ~CSIZE;
+                termios->c_cflag |= old_csize;
+                old_csize = CS8;
+        }
+
+        if ((termios->c_cflag & CSIZE) == CS8)
+                lcr_fcr = PNX8XXX_UART_LCR_8BIT;
+        else
+                lcr_fcr = 0;
+
+        if (termios->c_cflag & CSTOPB)
+                lcr_fcr |= PNX8XXX_UART_LCR_2STOPB;
+        if (termios->c_cflag & PARENB) {
+                lcr_fcr |= PNX8XXX_UART_LCR_PAREN;
+                if (!(termios->c_cflag & PARODD))
+                        lcr_fcr |= PNX8XXX_UART_LCR_PAREVN;
+        }
+
+        /*
+         * Ask the core to calculate the divisor for us.
+         */
+        baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+        quot = uart_get_divisor(port, baud);
+
+        spin_lock_irqsave(&sport->port.lock, flags);
+
+        sport->port.read_status_mask = ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN) |
+                                ISTAT_TO_SM(PNX8XXX_UART_INT_EMPTY) |
+                                ISTAT_TO_SM(PNX8XXX_UART_INT_RX);
+        if (termios->c_iflag & INPCK)
+                sport->port.read_status_mask |=
+                        FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
+                        FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR);
+        if (termios->c_iflag & (BRKINT | PARMRK))
+                sport->port.read_status_mask |=
+                        ISTAT_TO_SM(PNX8XXX_UART_INT_BREAK);
+
+        /*
+         * Characters to ignore
+         */
+        sport->port.ignore_status_mask = 0;
+        if (termios->c_iflag & IGNPAR)
+                sport->port.ignore_status_mask |=
+                        FIFO_TO_SM(PNX8XXX_UART_FIFO_RXFE) |
+                        FIFO_TO_SM(PNX8XXX_UART_FIFO_RXPAR);
+        if (termios->c_iflag & IGNBRK) {
+                sport->port.ignore_status_mask |=
+                        ISTAT_TO_SM(PNX8XXX_UART_INT_BREAK);
+                /*
+                 * If we're ignoring parity and break indicators,
+                 * ignore overruns too (for real raw support).
+                 */
+                if (termios->c_iflag & IGNPAR)
+                        sport->port.ignore_status_mask |=
+                                ISTAT_TO_SM(PNX8XXX_UART_INT_RXOVRN);
+        }
+
+        /*
+         * ignore all characters if CREAD is not set
+         */
+        if ((termios->c_cflag & CREAD) == 0)
+                sport->port.ignore_status_mask |=
+                        ISTAT_TO_SM(PNX8XXX_UART_INT_RX);
+
+        del_timer_sync(&sport->timer);
+
+        /*
+         * Update the per-port timeout.
+         */
+        uart_update_timeout(port, termios->c_cflag, baud);
+
+        /*
+         * disable interrupts and drain transmitter
+         */
+        old_ien = serial_in(sport, PNX8XXX_IEN);
+        serial_out(sport, PNX8XXX_IEN, old_ien & ~(PNX8XXX_UART_INT_ALLTX |
+                                        PNX8XXX_UART_INT_ALLRX));
+
+        while (serial_in(sport, PNX8XXX_FIFO) & PNX8XXX_UART_FIFO_TXFIFO_STA)
+                barrier();
+
+        /* then, disable everything */
+        serial_out(sport, PNX8XXX_IEN, 0);
+
+        /* Reset the Rx and Tx FIFOs too */
+        lcr_fcr |= PNX8XXX_UART_LCR_TX_RST;
+        lcr_fcr |= PNX8XXX_UART_LCR_RX_RST;
+
+        /* set the parity, stop bits and data size */
+        serial_out(sport, PNX8XXX_LCR, lcr_fcr);
+
+        /* set the baud rate */
+        quot -= 1;
+        serial_out(sport, PNX8XXX_BAUD, quot);
+
+        serial_out(sport, PNX8XXX_ICLR, -1);
+
+        serial_out(sport, PNX8XXX_IEN, old_ien);
+
+        if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
+                pnx8xxx_enable_ms(&sport->port);
+
+        spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+static const char *pnx8xxx_type(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+
+        return sport->port.type == PORT_PNX8XXX ? "PNX8XXX" : NULL;
+}
+
+/*
+ * Release the memory region(s) being used by 'port'.
+ */
+static void pnx8xxx_release_port(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+
+        release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
+}
+
+/*
+ * Request the memory region(s) being used by 'port'.
+ */
+static int pnx8xxx_request_port(struct uart_port *port)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
+                        "pnx8xxx-uart") != NULL ? 0 : -EBUSY;
+}
+
+/*
+ * Configure/autoconfigure the port.
+ */
+static void pnx8xxx_config_port(struct uart_port *port, int flags)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+
+        if (flags & UART_CONFIG_TYPE &&
+            pnx8xxx_request_port(&sport->port) == 0)
+                sport->port.type = PORT_PNX8XXX;
+}
+
+/*
+ * Verify the new serial_struct (for TIOCSSERIAL).
+ * The only change we allow are to the flags and type, and
+ * even then only between PORT_PNX8XXX and PORT_UNKNOWN
+ */
+static int
+pnx8xxx_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        int ret = 0;
+
+        if (ser->type != PORT_UNKNOWN && ser->type != PORT_PNX8XXX)
+                ret = -EINVAL;
+        if (sport->port.irq != ser->irq)
+                ret = -EINVAL;
+        if (ser->io_type != SERIAL_IO_MEM)
+                ret = -EINVAL;
+        if (sport->port.uartclk / 16 != ser->baud_base)
+                ret = -EINVAL;
+        if ((void *)sport->port.mapbase != ser->iomem_base)
+                ret = -EINVAL;
+        if (sport->port.iobase != ser->port)
+                ret = -EINVAL;
+        if (ser->hub6 != 0)
+                ret = -EINVAL;
+        return ret;
+}
+
+static struct uart_ops pnx8xxx_pops = {
+        .tx_empty       = pnx8xxx_tx_empty,
+        .set_mctrl      = pnx8xxx_set_mctrl,
+        .get_mctrl      = pnx8xxx_get_mctrl,
+        .stop_tx        = pnx8xxx_stop_tx,
+        .start_tx       = pnx8xxx_start_tx,
+        .stop_rx        = pnx8xxx_stop_rx,
+        .enable_ms      = pnx8xxx_enable_ms,
+        .break_ctl      = pnx8xxx_break_ctl,
+        .startup        = pnx8xxx_startup,
+        .shutdown       = pnx8xxx_shutdown,
+        .set_termios    = pnx8xxx_set_termios,
+        .type           = pnx8xxx_type,
+        .release_port   = pnx8xxx_release_port,
+        .request_port   = pnx8xxx_request_port,
+        .config_port    = pnx8xxx_config_port,
+        .verify_port    = pnx8xxx_verify_port,
+};
+
+
+/*
+ * Setup the PNX8XXX serial ports.
+ *
+ * Note also that we support "console=ttySx" where "x" is either 0 or 1.
+ */
+static void __init pnx8xxx_init_ports(void)
+{
+        static int first = 1;
+        int i;
+
+        if (!first)
+                return;
+        first = 0;
+
+        for (i = 0; i < NR_PORTS; i++) {
+                init_timer(&pnx8xxx_ports[i].timer);
+                pnx8xxx_ports[i].timer.function = pnx8xxx_timeout;
+                pnx8xxx_ports[i].timer.data     = (unsigned long)&pnx8xxx_ports[i];
+                pnx8xxx_ports[i].port.ops = &pnx8xxx_pops;
+        }
+}
+
+#ifdef CONFIG_SERIAL_PNX8XXX_CONSOLE
+
+static void pnx8xxx_console_putchar(struct uart_port *port, int ch)
+{
+        struct pnx8xxx_port *sport = (struct pnx8xxx_port *)port;
+        int status;
+
+        do {
+                /* Wait for UART_TX register to empty */
+                status = serial_in(sport, PNX8XXX_FIFO);
+        } while (status & PNX8XXX_UART_FIFO_TXFIFO);
+        serial_out(sport, PNX8XXX_FIFO, ch);
+}
+
+/*
+ * Interrupts are disabled on entering
+ */static void
+pnx8xxx_console_write(struct console *co, const char *s, unsigned int count)
+{
+        struct pnx8xxx_port *sport = &pnx8xxx_ports[co->index];
+        unsigned int old_ien, status;
+
+        /*
+         *      First, save IEN and then disable interrupts
+         */
+        old_ien = serial_in(sport, PNX8XXX_IEN);
+        serial_out(sport, PNX8XXX_IEN, old_ien & ~(PNX8XXX_UART_INT_ALLTX |
+                                        PNX8XXX_UART_INT_ALLRX));
+
+        uart_console_write(&sport->port, s, count, pnx8xxx_console_putchar);
+
+        /*
+         *      Finally, wait for transmitter to become empty
+         *      and restore IEN
+         */
+        do {
+                /* Wait for UART_TX register to empty */
+                status = serial_in(sport, PNX8XXX_FIFO);
+        } while (status & PNX8XXX_UART_FIFO_TXFIFO);
+
+        /* Clear TX and EMPTY interrupt */
+        serial_out(sport, PNX8XXX_ICLR, PNX8XXX_UART_INT_TX |
+                             PNX8XXX_UART_INT_EMPTY);
+
+        serial_out(sport, PNX8XXX_IEN, old_ien);
+}
+
+static int __init
+pnx8xxx_console_setup(struct console *co, char *options)
+{
+        struct pnx8xxx_port *sport;
+        int baud = 38400;
+        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 >= NR_PORTS)
+                co->index = 0;
+        sport = &pnx8xxx_ports[co->index];
+
+        if (options)
+                uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+        return uart_set_options(&sport->port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver pnx8xxx_reg;
+static struct console pnx8xxx_console = {
+        .name           = "ttyS",
+        .write          = pnx8xxx_console_write,
+        .device         = uart_console_device,
+        .setup          = pnx8xxx_console_setup,
+        .flags          = CON_PRINTBUFFER,
+        .index          = -1,
+        .data           = &pnx8xxx_reg,
+};
+
+static int __init pnx8xxx_rs_console_init(void)
+{
+        pnx8xxx_init_ports();
+        register_console(&pnx8xxx_console);
+        return 0;
+}
+console_initcall(pnx8xxx_rs_console_init);
+
+#define PNX8XXX_CONSOLE &pnx8xxx_console
+#else
+#define PNX8XXX_CONSOLE NULL
+#endif
+
+static struct uart_driver pnx8xxx_reg = {
+        .owner                  = THIS_MODULE,
+        .driver_name            = "ttyS",
+        .dev_name               = "ttyS",
+        .major                  = SERIAL_PNX8XXX_MAJOR,
+        .minor                  = MINOR_START,
+        .nr                     = NR_PORTS,
+        .cons                   = PNX8XXX_CONSOLE,
+};
+
+static int pnx8xxx_serial_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
+
+        return uart_suspend_port(&pnx8xxx_reg, &sport->port);
+}
+
+static int pnx8xxx_serial_resume(struct platform_device *pdev)
+{
+        struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
+
+        return uart_resume_port(&pnx8xxx_reg, &sport->port);
+}
+
+static int pnx8xxx_serial_probe(struct platform_device *pdev)
+{
+        struct resource *res = pdev->resource;
+        int i;
+
+        for (i = 0; i < pdev->num_resources; i++, res++) {
+                if (!(res->flags & IORESOURCE_MEM))
+                        continue;
+
+                for (i = 0; i < NR_PORTS; i++) {
+                        if (pnx8xxx_ports[i].port.mapbase != res->start)
+                                continue;
+
+                        pnx8xxx_ports[i].port.dev = &pdev->dev;
+                        uart_add_one_port(&pnx8xxx_reg, &pnx8xxx_ports[i].port);
+                        platform_set_drvdata(pdev, &pnx8xxx_ports[i]);
+                        break;
+                }
+        }
+
+        return 0;
+}
+
+static int pnx8xxx_serial_remove(struct platform_device *pdev)
+{
+        struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
+
+        platform_set_drvdata(pdev, NULL);
+
+        if (sport)
+                uart_remove_one_port(&pnx8xxx_reg, &sport->port);
+
+        return 0;
+}
+
+static struct platform_driver pnx8xxx_serial_driver = {
+        .driver         = {
+                .name   = "pnx8xxx-uart",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = pnx8xxx_serial_probe,
+        .remove         = pnx8xxx_serial_remove,
+        .suspend        = pnx8xxx_serial_suspend,
+        .resume         = pnx8xxx_serial_resume,
+};
+
+static int __init pnx8xxx_serial_init(void)
+{
+        int ret;
+
+        printk(KERN_INFO "Serial: PNX8XXX driver $Revision: 1.2 $\n");
+
+        pnx8xxx_init_ports();
+
+        ret = uart_register_driver(&pnx8xxx_reg);
+        if (ret == 0) {
+                ret = platform_driver_register(&pnx8xxx_serial_driver);
+                if (ret)
+                        uart_unregister_driver(&pnx8xxx_reg);
+        }
+        return ret;
+}
+
+static void __exit pnx8xxx_serial_exit(void)
+{
+        platform_driver_unregister(&pnx8xxx_serial_driver);
+        uart_unregister_driver(&pnx8xxx_reg);
+}
+
+module_init(pnx8xxx_serial_init);
+module_exit(pnx8xxx_serial_exit);
+
+MODULE_AUTHOR("Embedded Alley Solutions, Inc.");
+MODULE_DESCRIPTION("PNX8XXX SoCs serial port driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_PNX8XXX_MAJOR);