msm_serial: serial driver for MSM7K onboard serial peripheral.

Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 767 insertions, 0 deletions

diff --git a/drivers/serial/msm_serial.c b/drivers/serial/msm_serial.c
new file mode 100644
index 000000000000..1a7c856f76f8
--- /dev/null
+++ b/drivers/serial/msm_serial.c
@@ -0,0 +1,767 @@
+/*
+ * drivers/serial/msm_serial.c - driver for msm7k serial device and console
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Author: Robert Love <rlove@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#if defined(CONFIG_SERIAL_MSM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+# define SUPPORT_SYSRQ
+#endif
+
+#include <linux/hrtimer.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+
+#include "msm_serial.h"
+
+struct msm_port {
+        struct uart_port        uart;
+        char                    name[16];
+        struct clk              *clk;
+        unsigned int            imr;
+};
+
+#define UART_TO_MSM(uart_port)  ((struct msm_port *) uart_port)
+
+static inline void msm_write(struct uart_port *port, unsigned int val,
+                             unsigned int off)
+{
+        __raw_writel(val, port->membase + off);
+}
+
+static inline unsigned int msm_read(struct uart_port *port, unsigned int off)
+{
+        return __raw_readl(port->membase + off);
+}
+
+static void msm_stop_tx(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        msm_port->imr &= ~UART_IMR_TXLEV;
+        msm_write(port, msm_port->imr, UART_IMR);
+}
+
+static void msm_start_tx(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        msm_port->imr |= UART_IMR_TXLEV;
+        msm_write(port, msm_port->imr, UART_IMR);
+}
+
+static void msm_stop_rx(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
+        msm_write(port, msm_port->imr, UART_IMR);
+}
+
+static void msm_enable_ms(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        msm_port->imr |= UART_IMR_DELTA_CTS;
+        msm_write(port, msm_port->imr, UART_IMR);
+}
+
+static void handle_rx(struct uart_port *port)
+{
+        struct tty_struct *tty = port->info->port.tty;
+        unsigned int sr;
+
+        /*
+         * Handle overrun. My understanding of the hardware is that overrun
+         * is not tied to the RX buffer, so we handle the case out of band.
+         */
+        if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
+                port->icount.overrun++;
+                tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+                msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
+        }
+
+        /* and now the main RX loop */
+        while ((sr = msm_read(port, UART_SR)) & UART_SR_RX_READY) {
+                unsigned int c;
+                char flag = TTY_NORMAL;
+
+                c = msm_read(port, UART_RF);
+
+                if (sr & UART_SR_RX_BREAK) {
+                        port->icount.brk++;
+                        if (uart_handle_break(port))
+                                continue;
+                } else if (sr & UART_SR_PAR_FRAME_ERR) {
+                        port->icount.frame++;
+                } else {
+                        port->icount.rx++;
+                }
+
+                /* Mask conditions we're ignorning. */
+                sr &= port->read_status_mask;
+
+                if (sr & UART_SR_RX_BREAK) {
+                        flag = TTY_BREAK;
+                } else if (sr & UART_SR_PAR_FRAME_ERR) {
+                        flag = TTY_FRAME;
+                }
+
+                if (!uart_handle_sysrq_char(port, c))
+                        tty_insert_flip_char(tty, c, flag);
+        }
+
+        tty_flip_buffer_push(tty);
+}
+
+static void handle_tx(struct uart_port *port)
+{
+        struct circ_buf *xmit = &port->info->xmit;
+        struct msm_port *msm_port = UART_TO_MSM(port);
+        int sent_tx;
+
+        if (port->x_char) {
+                msm_write(port, port->x_char, UART_TF);
+                port->icount.tx++;
+                port->x_char = 0;
+        }
+
+        while (msm_read(port, UART_SR) & UART_SR_TX_READY) {
+                if (uart_circ_empty(xmit)) {
+                        /* disable tx interrupts */
+                        msm_port->imr &= ~UART_IMR_TXLEV;
+                        msm_write(port, msm_port->imr, UART_IMR);
+                        break;
+                }
+
+                msm_write(port, xmit->buf[xmit->tail], UART_TF);
+
+                xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+                port->icount.tx++;
+                sent_tx = 1;
+        }
+
+        if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+                uart_write_wakeup(port);
+}
+
+static void handle_delta_cts(struct uart_port *port)
+{
+        msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
+        port->icount.cts++;
+        wake_up_interruptible(&port->info->delta_msr_wait);
+}
+
+static irqreturn_t msm_irq(int irq, void *dev_id)
+{
+        struct uart_port *port = dev_id;
+        struct msm_port *msm_port = UART_TO_MSM(port);
+        unsigned int misr;
+
+        spin_lock(&port->lock);
+        misr = msm_read(port, UART_MISR);
+        msm_write(port, 0, UART_IMR); /* disable interrupt */
+
+        if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE))
+                handle_rx(port);
+        if (misr & UART_IMR_TXLEV)
+                handle_tx(port);
+        if (misr & UART_IMR_DELTA_CTS)
+                handle_delta_cts(port);
+
+        msm_write(port, msm_port->imr, UART_IMR); /* restore interrupt */
+        spin_unlock(&port->lock);
+
+        return IRQ_HANDLED;
+}
+
+static unsigned int msm_tx_empty(struct uart_port *port)
+{
+        return (msm_read(port, UART_SR) & UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
+}
+
+static unsigned int msm_get_mctrl(struct uart_port *port)
+{
+        return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
+}
+
+static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+        unsigned int mr;
+
+        mr = msm_read(port, UART_MR1);
+
+        if (!(mctrl & TIOCM_RTS)) {
+                mr &= ~UART_MR1_RX_RDY_CTL;
+                msm_write(port, mr, UART_MR1);
+                msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
+        } else {
+                mr |= UART_MR1_RX_RDY_CTL;
+                msm_write(port, mr, UART_MR1);
+        }
+}
+
+static void msm_break_ctl(struct uart_port *port, int break_ctl)
+{
+        if (break_ctl)
+                msm_write(port, UART_CR_CMD_START_BREAK, UART_CR);
+        else
+                msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
+}
+
+static void msm_set_baud_rate(struct uart_port *port, unsigned int baud)
+{
+        unsigned int baud_code, rxstale, watermark;
+
+        switch (baud) {
+        case 300:
+                baud_code = UART_CSR_300;
+                rxstale = 1;
+                break;
+        case 600:
+                baud_code = UART_CSR_600;
+                rxstale = 1;
+                break;
+        case 1200:
+                baud_code = UART_CSR_1200;
+                rxstale = 1;
+                break;
+        case 2400:
+                baud_code = UART_CSR_2400;
+                rxstale = 1;
+                break;
+        case 4800:
+                baud_code = UART_CSR_4800;
+                rxstale = 1;
+                break;
+        case 9600:
+                baud_code = UART_CSR_9600;
+                rxstale = 2;
+                break;
+        case 14400:
+                baud_code = UART_CSR_14400;
+                rxstale = 3;
+                break;
+        case 19200:
+                baud_code = UART_CSR_19200;
+                rxstale = 4;
+                break;
+        case 28800:
+                baud_code = UART_CSR_28800;
+                rxstale = 6;
+                break;
+        case 38400:
+                baud_code = UART_CSR_38400;
+                rxstale = 8;
+                break;
+        case 57600:
+                baud_code = UART_CSR_57600;
+                rxstale = 16;
+                break;
+        case 115200:
+        default:
+                baud_code = UART_CSR_115200;
+                rxstale = 31;
+                break;
+        }
+
+        msm_write(port, baud_code, UART_CSR);
+
+        /* RX stale watermark */
+        watermark = UART_IPR_STALE_LSB & rxstale;
+        watermark |= UART_IPR_RXSTALE_LAST;
+        watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
+        msm_write(port, watermark, UART_IPR);
+
+        /* set RX watermark */
+        watermark = (port->fifosize * 3) / 4;
+        msm_write(port, watermark, UART_RFWR);
+
+        /* set TX watermark */
+        msm_write(port, 10, UART_TFWR);
+}
+
+static void msm_reset(struct uart_port *port)
+{
+        /* reset everything */
+        msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
+        msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
+        msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
+        msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR);
+        msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
+        msm_write(port, UART_CR_CMD_SET_RFR, UART_CR);
+}
+
+static void msm_init_clock(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        clk_enable(msm_port->clk);
+
+        msm_write(port, 0xC0, UART_MREG);
+        msm_write(port, 0xB2, UART_NREG);
+        msm_write(port, 0x7D, UART_DREG);
+        msm_write(port, 0x1C, UART_MNDREG);
+}
+
+static int msm_startup(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+        unsigned int data, rfr_level;
+        int ret;
+
+        snprintf(msm_port->name, sizeof(msm_port->name),
+                 "msm_serial%d", port->line);
+
+        ret = request_irq(port->irq, msm_irq, IRQF_TRIGGER_HIGH,
+                          msm_port->name, port);
+        if (unlikely(ret))
+                return ret;
+
+        msm_init_clock(port);
+
+        if (likely(port->fifosize > 12))
+                rfr_level = port->fifosize - 12;
+        else
+                rfr_level = port->fifosize;
+
+        /* set automatic RFR level */
+        data = msm_read(port, UART_MR1);
+        data &= ~UART_MR1_AUTO_RFR_LEVEL1;
+        data &= ~UART_MR1_AUTO_RFR_LEVEL0;
+        data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
+        data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
+        msm_write(port, data, UART_MR1);
+
+        /* make sure that RXSTALE count is non-zero */
+        data = msm_read(port, UART_IPR);
+        if (unlikely(!data)) {
+                data |= UART_IPR_RXSTALE_LAST;
+                data |= UART_IPR_STALE_LSB;
+                msm_write(port, data, UART_IPR);
+        }
+
+        msm_reset(port);
+
+        msm_write(port, 0x05, UART_CR); /* enable TX & RX */
+
+        /* turn on RX and CTS interrupts */
+        msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE |
+                        UART_IMR_CURRENT_CTS;
+        msm_write(port, msm_port->imr, UART_IMR);
+
+        return 0;
+}
+
+static void msm_shutdown(struct uart_port *port)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        msm_port->imr = 0;
+        msm_write(port, 0, UART_IMR); /* disable interrupts */
+
+        clk_disable(msm_port->clk);
+
+        free_irq(port->irq, port);
+}
+
+static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
+                            struct ktermios *old)
+{
+        unsigned long flags;
+        unsigned int baud, mr;
+
+        spin_lock_irqsave(&port->lock, flags);
+
+        /* calculate and set baud rate */
+        baud = uart_get_baud_rate(port, termios, old, 300, 115200);
+        msm_set_baud_rate(port, baud);
+
+        /* calculate parity */
+        mr = msm_read(port, UART_MR2);
+        mr &= ~UART_MR2_PARITY_MODE;
+        if (termios->c_cflag & PARENB) {
+                if (termios->c_cflag & PARODD)
+                        mr |= UART_MR2_PARITY_MODE_ODD;
+                else if (termios->c_cflag & CMSPAR)
+                        mr |= UART_MR2_PARITY_MODE_SPACE;
+                else
+                        mr |= UART_MR2_PARITY_MODE_EVEN;
+        }
+
+        /* calculate bits per char */
+        mr &= ~UART_MR2_BITS_PER_CHAR;
+        switch (termios->c_cflag & CSIZE) {
+        case CS5:
+                mr |= UART_MR2_BITS_PER_CHAR_5;
+                break;
+        case CS6:
+                mr |= UART_MR2_BITS_PER_CHAR_6;
+                break;
+        case CS7:
+                mr |= UART_MR2_BITS_PER_CHAR_7;
+                break;
+        case CS8:
+        default:
+                mr |= UART_MR2_BITS_PER_CHAR_8;
+                break;
+        }
+
+        /* calculate stop bits */
+        mr &= ~(UART_MR2_STOP_BIT_LEN_ONE | UART_MR2_STOP_BIT_LEN_TWO);
+        if (termios->c_cflag & CSTOPB)
+                mr |= UART_MR2_STOP_BIT_LEN_TWO;
+        else
+                mr |= UART_MR2_STOP_BIT_LEN_ONE;
+
+        /* set parity, bits per char, and stop bit */
+        msm_write(port, mr, UART_MR2);
+
+        /* calculate and set hardware flow control */
+        mr = msm_read(port, UART_MR1);
+        mr &= ~(UART_MR1_CTS_CTL | UART_MR1_RX_RDY_CTL);
+        if (termios->c_cflag & CRTSCTS) {
+                mr |= UART_MR1_CTS_CTL;
+                mr |= UART_MR1_RX_RDY_CTL;
+        }
+        msm_write(port, mr, UART_MR1);
+
+        /* Configure status bits to ignore based on termio flags. */
+        port->read_status_mask = 0;
+        if (termios->c_iflag & INPCK)
+                port->read_status_mask |= UART_SR_PAR_FRAME_ERR;
+        if (termios->c_iflag & (BRKINT | PARMRK))
+                port->read_status_mask |= UART_SR_RX_BREAK;
+
+        uart_update_timeout(port, termios->c_cflag, baud);
+
+        spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *msm_type(struct uart_port *port)
+{
+        return "MSM";
+}
+
+static void msm_release_port(struct uart_port *port)
+{
+        struct platform_device *pdev = to_platform_device(port->dev);
+        struct resource *resource;
+        resource_size_t size;
+
+        resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (unlikely(!resource))
+                return;
+        size = resource->end - resource->start + 1;
+
+        release_mem_region(port->mapbase, size);
+        iounmap(port->membase);
+        port->membase = NULL;
+}
+
+static int msm_request_port(struct uart_port *port)
+{
+        struct platform_device *pdev = to_platform_device(port->dev);
+        struct resource *resource;
+        resource_size_t size;
+
+        resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (unlikely(!resource))
+                return -ENXIO;
+        size = resource->end - resource->start + 1;
+
+        if (unlikely(!request_mem_region(port->mapbase, size, "msm_serial")))
+                return -EBUSY;
+
+        port->membase = ioremap(port->mapbase, size);
+        if (!port->membase) {
+                release_mem_region(port->mapbase, size);
+                return -EBUSY;
+        }
+
+        return 0;
+}
+
+static void msm_config_port(struct uart_port *port, int flags)
+{
+        if (flags & UART_CONFIG_TYPE) {
+                port->type = PORT_MSM;
+                msm_request_port(port);
+        }
+}
+
+static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+        if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
+                return -EINVAL;
+        if (unlikely(port->irq != ser->irq))
+                return -EINVAL;
+        return 0;
+}
+
+static void msm_power(struct uart_port *port, unsigned int state,
+                      unsigned int oldstate)
+{
+        struct msm_port *msm_port = UART_TO_MSM(port);
+
+        switch (state) {
+        case 0:
+                clk_enable(msm_port->clk);
+                break;
+        case 3:
+                clk_disable(msm_port->clk);
+                break;
+        default:
+                printk(KERN_ERR "msm_serial: Unknown PM state %d\n", state);
+        }
+}
+
+static struct uart_ops msm_uart_pops = {
+        .tx_empty = msm_tx_empty,
+        .set_mctrl = msm_set_mctrl,
+        .get_mctrl = msm_get_mctrl,
+        .stop_tx = msm_stop_tx,
+        .start_tx = msm_start_tx,
+        .stop_rx = msm_stop_rx,
+        .enable_ms = msm_enable_ms,
+        .break_ctl = msm_break_ctl,
+        .startup = msm_startup,
+        .shutdown = msm_shutdown,
+        .set_termios = msm_set_termios,
+        .type = msm_type,
+        .release_port = msm_release_port,
+        .request_port = msm_request_port,
+        .config_port = msm_config_port,
+        .verify_port = msm_verify_port,
+        .pm = msm_power,
+};
+
+static struct msm_port msm_uart_ports[] = {
+        {
+                .uart = {
+                        .iotype = UPIO_MEM,
+                        .ops = &msm_uart_pops,
+                        .flags = UPF_BOOT_AUTOCONF,
+                        .fifosize = 512,
+                        .line = 0,
+                },
+        },
+        {
+                .uart = {
+                        .iotype = UPIO_MEM,
+                        .ops = &msm_uart_pops,
+                        .flags = UPF_BOOT_AUTOCONF,
+                        .fifosize = 512,
+                        .line = 1,
+                },
+        },
+        {
+                .uart = {
+                        .iotype = UPIO_MEM,
+                        .ops = &msm_uart_pops,
+                        .flags = UPF_BOOT_AUTOCONF,
+                        .fifosize = 64,
+                        .line = 2,
+                },
+        },
+};
+
+#define UART_NR ARRAY_SIZE(msm_uart_ports)
+
+static inline struct uart_port *get_port_from_line(unsigned int line)
+{
+        return &msm_uart_ports[line].uart;
+}
+
+#ifdef CONFIG_SERIAL_MSM_CONSOLE
+
+static void msm_console_putchar(struct uart_port *port, int c)
+{
+        while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
+                ;
+        msm_write(port, c, UART_TF);
+}
+
+static void msm_console_write(struct console *co, const char *s,
+                              unsigned int count)
+{
+        struct uart_port *port;
+        struct msm_port *msm_port;
+
+        BUG_ON(co->index < 0 || co->index >= UART_NR);
+
+        port = get_port_from_line(co->index);
+        msm_port = UART_TO_MSM(port);
+
+        spin_lock(&port->lock);
+        uart_console_write(port, s, count, msm_console_putchar);
+        spin_unlock(&port->lock);
+}
+
+static int __init msm_console_setup(struct console *co, char *options)
+{
+        struct uart_port *port;
+        int baud, flow, bits, parity;
+
+        if (unlikely(co->index >= UART_NR || co->index < 0))
+                return -ENXIO;
+
+        port = get_port_from_line(co->index);
+
+        if (unlikely(!port->membase))
+                return -ENXIO;
+
+        port->cons = co;
+
+        msm_init_clock(port);
+
+        if (options)
+                uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+        bits = 8;
+        parity = 'n';
+        flow = 'n';
+        msm_write(port, UART_MR2_BITS_PER_CHAR_8 | UART_MR2_STOP_BIT_LEN_ONE,
+                  UART_MR2);    /* 8N1 */
+
+        if (baud < 300 || baud > 115200)
+                baud = 115200;
+        msm_set_baud_rate(port, baud);
+
+        msm_reset(port);
+
+        printk(KERN_INFO "msm_serial: console setup on port #%d\n", port->line);
+
+        return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver msm_uart_driver;
+
+static struct console msm_console = {
+        .name = "ttyMSM",
+        .write = msm_console_write,
+        .device = uart_console_device,
+        .setup = msm_console_setup,
+        .flags = CON_PRINTBUFFER,
+        .index = -1,
+        .data = &msm_uart_driver,
+};
+
+#define MSM_CONSOLE     (&msm_console)
+
+#else
+#define MSM_CONSOLE     NULL
+#endif
+
+static struct uart_driver msm_uart_driver = {
+        .owner = THIS_MODULE,
+        .driver_name = "msm_serial",
+        .dev_name = "ttyMSM",
+        .nr = UART_NR,
+        .cons = MSM_CONSOLE,
+};
+
+static int __init msm_serial_probe(struct platform_device *pdev)
+{
+        struct msm_port *msm_port;
+        struct resource *resource;
+        struct uart_port *port;
+
+        if (unlikely(pdev->id < 0 || pdev->id >= UART_NR))
+                return -ENXIO;
+
+        printk(KERN_INFO "msm_serial: detected port #%d\n", pdev->id);
+
+        port = get_port_from_line(pdev->id);
+        port->dev = &pdev->dev;
+        msm_port = UART_TO_MSM(port);
+
+        msm_port->clk = clk_get(&pdev->dev, "uart_clk");
+        if (unlikely(IS_ERR(msm_port->clk)))
+                return PTR_ERR(msm_port->clk);
+        port->uartclk = clk_get_rate(msm_port->clk);
+
+        resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (unlikely(!resource))
+                return -ENXIO;
+        port->mapbase = resource->start;
+
+        port->irq = platform_get_irq(pdev, 0);
+        if (unlikely(port->irq < 0))
+                return -ENXIO;
+
+        platform_set_drvdata(pdev, port);
+
+        return uart_add_one_port(&msm_uart_driver, port);
+}
+
+static int __devexit msm_serial_remove(struct platform_device *pdev)
+{
+        struct msm_port *msm_port = platform_get_drvdata(pdev);
+
+        clk_put(msm_port->clk);
+
+        return 0;
+}
+
+static struct platform_driver msm_platform_driver = {
+        .probe = msm_serial_probe,
+        .remove = msm_serial_remove,
+        .driver = {
+                .name = "msm_serial",
+                .owner = THIS_MODULE,
+        },
+};
+
+static int __init msm_serial_init(void)
+{
+        int ret;
+
+        ret = uart_register_driver(&msm_uart_driver);
+        if (unlikely(ret))
+                return ret;
+
+        ret = platform_driver_probe(&msm_platform_driver, msm_serial_probe);
+        if (unlikely(ret))
+                uart_unregister_driver(&msm_uart_driver);
+
+        printk(KERN_INFO "msm_serial: driver initialized\n");
+
+        return ret;
+}
+
+static void __exit msm_serial_exit(void)
+{
+#ifdef CONFIG_SERIAL_MSM_CONSOLE
+        unregister_console(&msm_console);
+#endif
+        platform_driver_unregister(&msm_platform_driver);
+        uart_unregister_driver(&msm_uart_driver);
+}
+
+module_init(msm_serial_init);
+module_exit(msm_serial_exit);
+
+MODULE_AUTHOR("Robert Love <rlove@google.com>");
+MODULE_DESCRIPTION("Driver for msm7x serial device");
+MODULE_LICENSE("GPL");