/*
 * mos7720.c
 *   Controls the Moschip 7720 usb to dual port serial convertor
 *
 * Copyright 2006 Moschip Semiconductor Tech. Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 2 of the License.
 *
 * Developed by:
 *      Vijaya Kumar <vijaykumar.gn@gmail.com>
 *      Ajay Kumar <naanuajay@yahoo.com>
 *      Gurudeva <ngurudeva@yahoo.com>
 *
 * Cleaned up from the original by:
 *      Greg Kroah-Hartman <gregkh@suse.de>
 *
 * Originally based on drivers/usb/serial/io_edgeport.c which is:
 *      Copyright (C) 2000 Inside Out Networks, All rights reserved.
 *      Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
 */
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/serial.h>
#include <linux/serial_reg.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/uaccess.h>


/*
 * Version Information
 */
#define DRIVER_VERSION "1.0.0.4F"
#define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
#define DRIVER_DESC "Moschip USB Serial Driver"

/* default urb timeout */
#define MOS_WDR_TIMEOUT (HZ * 5)

#define MOS_PORT1       0x0200
#define MOS_PORT2       0x0300
#define MOS_VENREG      0x0000
#define MOS_MAX_PORT    0x02
#define MOS_WRITE       0x0E
#define MOS_READ        0x0D

/* Interrupt Rotinue Defines    */
#define SERIAL_IIR_RLS  0x06
#define SERIAL_IIR_RDA  0x04
#define SERIAL_IIR_CTI  0x0c
#define SERIAL_IIR_THR  0x02
#define SERIAL_IIR_MS   0x00

#define NUM_URBS                        16      /* URB Count */
#define URB_TRANSFER_BUFFER_SIZE        32      /* URB Size */

/* This structure holds all of the local port information */
struct moschip_port {
        __u8    shadowLCR;              /* last LCR value received */
        __u8    shadowMCR;              /* last MCR value received */
        __u8    shadowMSR;              /* last MSR value received */
        char                    open;
        struct async_icount     icount;
        struct usb_serial_port  *port;  /* loop back to the owner */
        struct urb              *write_urb_pool[NUM_URBS];
};

/* This structure holds all of the individual serial device information */
struct moschip_serial {
        int interrupt_started;
};

static int debug;

#define USB_VENDOR_ID_MOSCHIP           0x9710
#define MOSCHIP_DEVICE_ID_7720          0x7720
#define MOSCHIP_DEVICE_ID_7715          0x7715

static struct usb_device_id moschip_port_id_table[] = {
        { USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
        { } /* terminating entry */
};
MODULE_DEVICE_TABLE(usb, moschip_port_id_table);


/*
 * mos7720_interrupt_callback
 *      this is the callback function for when we have received data on the
 *      interrupt endpoint.
 */
static void mos7720_interrupt_callback(struct urb *urb)
{
        int result;
        int length;
        int status = urb->status;
        __u8 *data;
        __u8 sp1;
        __u8 sp2;

        dbg("%s", " : Entering\n");

        switch (status) {
        case 0:
                /* success */
                break;
        case -ECONNRESET:
        case -ENOENT:
        case -ESHUTDOWN:
                /* this urb is terminated, clean up */
                dbg("%s - urb shutting down with status: %d", __func__,
                    status);
                return;
        default:
                dbg("%s - nonzero urb status received: %d", __func__,
                    status);
                goto exit;
        }

        length = urb->actual_length;
        data = urb->transfer_buffer;

        /* Moschip get 4 bytes
         * Byte 1 IIR Port 1 (port.number is 0)
         * Byte 2 IIR Port 2 (port.number is 1)
         * Byte 3 --------------
         * Byte 4 FIFO status for both */

        /* the above description is inverted
         *      oneukum 2007-03-14 */

        if (unlikely(length != 4)) {
                dbg("Wrong data !!!");
                return;
        }

        sp1 = data[3];
        sp2 = data[2];

        if ((sp1 | sp2) & 0x01) {
                /* No Interrupt Pending in both the ports */
                dbg("No Interrupt !!!");
        } else {
                switch (sp1 & 0x0f) {
                case SERIAL_IIR_RLS:
                        dbg("Serial Port 1: Receiver status error or address "
                            "bit detected in 9-bit mode\n");
                        break;
                case SERIAL_IIR_CTI:
                        dbg("Serial Port 1: Receiver time out");
                        break;
                case SERIAL_IIR_MS:
                        dbg("Serial Port 1: Modem status change");
                        break;
                }

                switch (sp2 & 0x0f) {
                case SERIAL_IIR_RLS:
                        dbg("Serial Port 2: Receiver status error or address "
                            "bit detected in 9-bit mode");
                        break;
                case SERIAL_IIR_CTI:
                        dbg("Serial Port 2: Receiver time out");
                        break;
                case SERIAL_IIR_MS:
                        dbg("Serial Port 2: Modem status change");
                        break;
                }
        }

exit:
        result = usb_submit_urb(urb, GFP_ATOMIC);
        if (result)
                dev_err(&urb->dev->dev,
                        "%s - Error %d submitting control urb\n",
                        __func__, result);
        return;
}

/*
 * mos7720_bulk_in_callback
 *      this is the callback function for when we have received data on the
 *      bulk in endpoint.
 */
static void mos7720_bulk_in_callback(struct urb *urb)
{
        int retval;
        unsigned char *data ;
        struct usb_serial_port *port;
        struct moschip_port *mos7720_port;
        struct tty_struct *tty;
        int status = urb->status;

        if (status) {
                dbg("nonzero read bulk status received: %d", status);
                return;
        }

        mos7720_port = urb->context;
        if (!mos7720_port) {
                dbg("%s", "NULL mos7720_port pointer \n");
                return ;
        }

        port = mos7720_port->port;

        dbg("Entering...%s", __func__);

        data = urb->transfer_buffer;

        tty = tty_port_tty_get(&port->port);
        if (tty && urb->actual_length) {
                tty_buffer_request_room(tty, urb->actual_length);
                tty_insert_flip_string(tty, data, urb->actual_length);
                tty_flip_buffer_push(tty);
        }
        tty_kref_put(tty);

        if (!port->read_urb) {
                dbg("URB KILLED !!!");
                return;
        }

        if (port->read_urb->status != -EINPROGRESS) {
                port->read_urb->dev = port->serial->dev;

                retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
                if (retval)
                        dbg("usb_submit_urb(read bulk) failed, retval = %d",
                            retval);
        }
}

/*
 * mos7720_bulk_out_data_callback
 *      this is the callback function for when we have finished sending serial
 *      data on the bulk out endpoint.
 */
static void mos7720_bulk_out_data_callback(struct urb *urb)
{
        struct moschip_port *mos7720_port;
        struct tty_struct *tty;
        int status = urb->status;

        if (status) {
                dbg("nonzero write bulk status received:%d", status);
                return;
        }

        mos7720_port = urb->context;
        if (!mos7720_port) {
                dbg("NULL mos7720_port pointer");
                return ;
        }

        dbg("Entering .........");

        tty = tty_port_tty_get(&mos7720_port->port->port);

        if (tty && mos7720_port->open)
                tty_wakeup(tty);
        tty_kref_put(tty);
}

/*
 * send_mos_cmd
 *      this function will be used for sending command to device
 */
static int send_mos_cmd(struct usb_serial *serial, __u8 request, __u16 value,
                        __u16 index, void *data)
{
        int status;
        unsigned int pipe;
        u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
        __u8 requesttype;
        __u16 size = 0x0000;

        if (value < MOS_MAX_PORT) {
                if (product == MOSCHIP_DEVICE_ID_7715)
                        value = value*0x100+0x100;
                else
                        value = value*0x100+0x200;
        } else {
                value = 0x0000;
                if ((product == MOSCHIP_DEVICE_ID_7715) &&
                    (index != 0x08)) {
                        dbg("serial->product== MOSCHIP_DEVICE_ID_7715");
                        /* index = 0x01 ; */
                }
        }

        if (request == MOS_WRITE) {
                request = (__u8)MOS_WRITE;
                requesttype = (__u8)0x40;
                value  = value + (__u16)*((unsigned char *)data);
                data = NULL;
                pipe = usb_sndctrlpipe(serial->dev, 0);
        } else {
                request = (__u8)MOS_READ;
                requesttype = (__u8)0xC0;
                size = 0x01;
                pipe = usb_rcvctrlpipe(serial->dev, 0);
        }

        status = usb_control_msg(serial->dev, pipe, request, requesttype,
                                 value, index, data, size, MOS_WDR_TIMEOUT);

        if (status < 0)
                dbg("Command Write failed Value %x index %x\n", value, index);

        return status;
}

static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
{
        struct usb_serial *serial;
        struct usb_serial_port *port0;
        struct urb *urb;
        struct moschip_serial *mos7720_serial;
        struct moschip_port *mos7720_port;
        int response;
        int port_number;
        char data;
        int allocated_urbs = 0;
        int j;

        serial = port->serial;

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL)
                return -ENODEV;

        port0 = serial->port[0];

        mos7720_serial = usb_get_serial_data(serial);

        if (mos7720_serial == NULL || port0 == NULL)
                return -ENODEV;

        usb_clear_halt(serial->dev, port->write_urb->pipe);
        usb_clear_halt(serial->dev, port->read_urb->pipe);

        /* Initialising the write urb pool */
        for (j = 0; j < NUM_URBS; ++j) {
                urb = usb_alloc_urb(0, GFP_KERNEL);
                mos7720_port->write_urb_pool[j] = urb;

                if (urb == NULL) {
                        dev_err(&port->dev, "No more urbs???\n");
                        continue;
                }

                urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
                                               GFP_KERNEL);
                if (!urb->transfer_buffer) {
                        dev_err(&port->dev,
                                "%s-out of memory for urb buffers.\n",
                                __func__);
                        usb_free_urb(mos7720_port->write_urb_pool[j]);
                        mos7720_port->write_urb_pool[j] = NULL;
                        continue;
                }
                allocated_urbs++;
        }

        if (!allocated_urbs)
                return -ENOMEM;

         /* Initialize MCS7720 -- Write Init values to corresponding Registers
          *
          * Register Index
          * 0 : THR/RHR
          * 1 : IER
          * 2 : FCR
          * 3 : LCR
          * 4 : MCR
          * 5 : LSR
          * 6 : MSR
          * 7 : SPR
          *
          * 0x08 : SP1/2 Control Reg
          */
        port_number = port->number - port->serial->minor;
        send_mos_cmd(port->serial, MOS_READ, port_number, UART_LSR, &data);
        dbg("SS::%p LSR:%x\n", mos7720_port, data);

        dbg("Check:Sending Command ..........");

        data = 0x02;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, 0x01, &data);
        data = 0x02;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, 0x02, &data);

        data = 0x00;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x01, &data);
        data = 0x00;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x02, &data);

        data = 0xCF;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x02, &data);
        data = 0x03;
        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x03, &data);
        data = 0x0b;
        mos7720_port->shadowMCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);
        data = 0x0b;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);

        data = 0x00;
        send_mos_cmd(serial, MOS_READ, MOS_MAX_PORT, 0x08, &data);
        data = 0x00;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, 0x08, &data);

/*      data = 0x00;
        send_mos_cmd(serial, MOS_READ, MOS_MAX_PORT, port_number + 1, &data);
        data = 0x03;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, port_number + 1, &data);
        data = 0x00;
        send_mos_cmd(port->serial, MOS_WRITE, MOS_MAX_PORT,
                                                port_number + 1, &data);
*/
        data = 0x00;
        send_mos_cmd(serial, MOS_READ, MOS_MAX_PORT, 0x08, &data);

        data = data | (port->number - port->serial->minor + 1);
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, 0x08, &data);

        data = 0x83;
        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x03, &data);
        data = 0x0c;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x00, &data);
        data = 0x00;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x01, &data);
        data = 0x03;
        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x03, &data);
        data = 0x0c;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x01, &data);
        data = 0x0c;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x01, &data);

        /* see if we've set up our endpoint info yet   *
         * (can't set it up in mos7720_startup as the  *
         * structures were not set up at that time.)   */
        if (!mos7720_serial->interrupt_started) {
                dbg("Interrupt buffer NULL !!!");

                /* not set up yet, so do it now */
                mos7720_serial->interrupt_started = 1;

                dbg("To Submit URB !!!");

                /* set up our interrupt urb */
                usb_fill_int_urb(port0->interrupt_in_urb, serial->dev,
                         usb_rcvintpipe(serial->dev,
                                port->interrupt_in_endpointAddress),
                         port0->interrupt_in_buffer,
                         port0->interrupt_in_urb->transfer_buffer_length,
                         mos7720_interrupt_callback, mos7720_port,
                         port0->interrupt_in_urb->interval);

                /* start interrupt read for this mos7720 this interrupt *
                 * will continue as long as the mos7720 is connected    */
                dbg("Submit URB over !!!");
                response = usb_submit_urb(port0->interrupt_in_urb, GFP_KERNEL);
                if (response)
                        dev_err(&port->dev,
                                "%s - Error %d submitting control urb\n",
                                __func__, response);
        }

        /* set up our bulk in urb */
        usb_fill_bulk_urb(port->read_urb, serial->dev,
                          usb_rcvbulkpipe(serial->dev,
                                port->bulk_in_endpointAddress),
                          port->bulk_in_buffer,
                          port->read_urb->transfer_buffer_length,
                          mos7720_bulk_in_callback, mos7720_port);
        response = usb_submit_urb(port->read_urb, GFP_KERNEL);
        if (response)
                dev_err(&port->dev, "%s - Error %d submitting read urb\n",
                                                        __func__, response);

        /* initialize our icount structure */
        memset(&(mos7720_port->icount), 0x00, sizeof(mos7720_port->icount));

        /* initialize our port settings */
        mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */

        /* send a open port command */
        mos7720_port->open = 1;

        return 0;
}

/*
 * mos7720_chars_in_buffer
 *      this function is called by the tty driver when it wants to know how many
 *      bytes of data we currently have outstanding in the port (data that has
 *      been written, but hasn't made it out the port yet)
 *      If successful, we return the number of bytes left to be written in the
 *      system,
 *      Otherwise we return a negative error number.
 */
static int mos7720_chars_in_buffer(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        int i;
        int chars = 0;
        struct moschip_port *mos7720_port;

        dbg("%s:entering ...........", __func__);

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL) {
                dbg("%s:leaving ...........", __func__);
                return 0;
        }

        for (i = 0; i < NUM_URBS; ++i) {
                if (mos7720_port->write_urb_pool[i] &&
                    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
                        chars += URB_TRANSFER_BUFFER_SIZE;
        }
        dbg("%s - returns %d", __func__, chars);
        return chars;
}

static void mos7720_close(struct usb_serial_port *port)
{
        struct usb_serial *serial;
        struct moschip_port *mos7720_port;
        char data;
        int j;

        dbg("mos7720_close:entering...");

        serial = port->serial;

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL)
                return;

        for (j = 0; j < NUM_URBS; ++j)
                usb_kill_urb(mos7720_port->write_urb_pool[j]);

        /* Freeing Write URBs */
        for (j = 0; j < NUM_URBS; ++j) {
                if (mos7720_port->write_urb_pool[j]) {
                        kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
                        usb_free_urb(mos7720_port->write_urb_pool[j]);
                }
        }

        /* While closing port, shutdown all bulk read, write  *
         * and interrupt read if they exists, otherwise nop   */
        dbg("Shutdown bulk write");
        usb_kill_urb(port->write_urb);
        dbg("Shutdown bulk read");
        usb_kill_urb(port->read_urb);

        mutex_lock(&serial->disc_mutex);
        /* these commands must not be issued if the device has
         * been disconnected */
        if (!serial->disconnected) {
                data = 0x00;
                send_mos_cmd(serial, MOS_WRITE,
                        port->number - port->serial->minor, 0x04, &data);

                data = 0x00;
                send_mos_cmd(serial, MOS_WRITE,
                        port->number - port->serial->minor, 0x01, &data);
        }
        mutex_unlock(&serial->disc_mutex);
        mos7720_port->open = 0;

        dbg("Leaving %s", __func__);
}

static void mos7720_break(struct tty_struct *tty, int break_state)
{
        struct usb_serial_port *port = tty->driver_data;
        unsigned char data;
        struct usb_serial *serial;
        struct moschip_port *mos7720_port;

        dbg("Entering %s", __func__);

        serial = port->serial;

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL)
                return;

        if (break_state == -1)
                data = mos7720_port->shadowLCR | UART_LCR_SBC;
        else
                data = mos7720_port->shadowLCR & ~UART_LCR_SBC;

        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port->number - port->serial->minor,
                     0x03, &data);

        return;
}

/*
 * mos7720_write_room
 *      this function is called by the tty driver when it wants to know how many
 *      bytes of data we can accept for a specific port.
 *      If successful, we return the amount of room that we have for this port
 *      Otherwise we return a negative error number.
 */
static int mos7720_write_room(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct moschip_port *mos7720_port;
        int room = 0;
        int i;

        dbg("%s:entering ...........", __func__);

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL) {
                dbg("%s:leaving ...........", __func__);
                return -ENODEV;
        }

        /* FIXME: Locking */
        for (i = 0; i < NUM_URBS; ++i) {
                if (mos7720_port->write_urb_pool[i] &&
                    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
                        room += URB_TRANSFER_BUFFER_SIZE;
        }

        dbg("%s - returns %d", __func__, room);
        return room;
}

static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
                                 const unsigned char *data, int count)
{
        int status;
        int i;
        int bytes_sent = 0;
        int transfer_size;

        struct moschip_port *mos7720_port;
        struct usb_serial *serial;
        struct urb    *urb;
        const unsigned char *current_position = data;

        dbg("%s:entering ...........", __func__);

        serial = port->serial;

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL) {
                dbg("mos7720_port is NULL");
                return -ENODEV;
        }

        /* try to find a free urb in the list */
        urb = NULL;

        for (i = 0; i < NUM_URBS; ++i) {
                if (mos7720_port->write_urb_pool[i] &&
                    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
                        urb = mos7720_port->write_urb_pool[i];
                        dbg("URB:%d", i);
                        break;
                }
        }

        if (urb == NULL) {
                dbg("%s - no more free urbs", __func__);
                goto exit;
        }

        if (urb->transfer_buffer == NULL) {
                urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
                                               GFP_KERNEL);
                if (urb->transfer_buffer == NULL) {
                        dev_err(&port->dev, "%s no more kernel memory...\n",
                                __func__);
                        goto exit;
                }
        }
        transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);

        memcpy(urb->transfer_buffer, current_position, transfer_size);
        usb_serial_debug_data(debug, &port->dev, __func__, transfer_size,
                              urb->transfer_buffer);

        /* fill urb with data and submit  */
        usb_fill_bulk_urb(urb, serial->dev,
                          usb_sndbulkpipe(serial->dev,
                                        port->bulk_out_endpointAddress),
                          urb->transfer_buffer, transfer_size,
                          mos7720_bulk_out_data_callback, mos7720_port);

        /* send it down the pipe */
        status = usb_submit_urb(urb, GFP_ATOMIC);
        if (status) {
                dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed "
                        "with status = %d\n", __func__, status);
                bytes_sent = status;
                goto exit;
        }
        bytes_sent = transfer_size;

exit:
        return bytes_sent;
}

static void mos7720_throttle(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct moschip_port *mos7720_port;
        int status;

        dbg("%s- port %d\n", __func__, port->number);

        mos7720_port = usb_get_serial_port_data(port);

        if (mos7720_port == NULL)
                return;

        if (!mos7720_port->open) {
                dbg("port not opened");
                return;
        }

        dbg("%s: Entering ..........", __func__);

        /* if we are implementing XON/XOFF, send the stop character */
        if (I_IXOFF(tty)) {
                unsigned char stop_char = STOP_CHAR(tty);
                status = mos7720_write(tty, port, &stop_char, 1);
                if (status <= 0)
                        return;
        }

        /* if we are implementing RTS/CTS, toggle that line */
        if (tty->termios->c_cflag & CRTSCTS) {
                mos7720_port->shadowMCR &= ~UART_MCR_RTS;
                status = send_mos_cmd(port->serial, MOS_WRITE,
                                      port->number - port->serial->minor,
                                      UART_MCR, &mos7720_port->shadowMCR);
                if (status != 0)
                        return;
        }
}

static void mos7720_unthrottle(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
        int status;

        if (mos7720_port == NULL)
                return;

        if (!mos7720_port->open) {
                dbg("%s - port not opened", __func__);
                return;
        }

        dbg("%s: Entering ..........", __func__);

        /* if we are implementing XON/XOFF, send the start character */
        if (I_IXOFF(tty)) {
                unsigned char start_char = START_CHAR(tty);
                status = mos7720_write(tty, port, &start_char, 1);
                if (status <= 0)
                        return;
        }

        /* if we are implementing RTS/CTS, toggle that line */
        if (tty->termios->c_cflag & CRTSCTS) {
                mos7720_port->shadowMCR |= UART_MCR_RTS;
                status = send_mos_cmd(port->serial, MOS_WRITE,
                                      port->number - port->serial->minor,
                                      UART_MCR, &mos7720_port->shadowMCR);
                if (status != 0)
                        return;
        }
}

static int set_higher_rates(struct moschip_port *mos7720_port,
                            unsigned int baud)
{
        unsigned char data;
        struct usb_serial_port *port;
        struct usb_serial *serial;
        int port_number;

        if (mos7720_port == NULL)
                return -EINVAL;

        port = mos7720_port->port;
        serial = port->serial;

         /***********************************************
         *      Init Sequence for higher rates
         ***********************************************/
        dbg("Sending Setting Commands ..........");
        port_number = port->number - port->serial->minor;

        data = 0x000;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x01, &data);
        data = 0x000;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x02, &data);
        data = 0x0CF;
        send_mos_cmd(serial, MOS_WRITE, port->number, 0x02, &data);
        data = 0x00b;
        mos7720_port->shadowMCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);
        data = 0x00b;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);

        data = 0x000;
        send_mos_cmd(serial, MOS_READ, MOS_MAX_PORT, 0x08, &data);
        data = 0x000;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, 0x08, &data);


        /***********************************************
         *              Set for higher rates           *
         ***********************************************/

        data = baud * 0x10;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, port_number + 1, &data);

        data = 0x003;
        send_mos_cmd(serial, MOS_READ, MOS_MAX_PORT, 0x08, &data);
        data = 0x003;
        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT, 0x08, &data);

        data = 0x02b;
        mos7720_port->shadowMCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);
        data = 0x02b;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);

        /***********************************************
         *              Set DLL/DLM
         ***********************************************/

        data = mos7720_port->shadowLCR | UART_LCR_DLAB;
        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x03, &data);

        data =  0x001; /* DLL */
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x00, &data);
        data =  0x000; /* DLM */
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x01, &data);

        data = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x03, &data);

        return 0;
}

/* baud rate information */
struct divisor_table_entry {
        __u32  baudrate;
        __u16  divisor;
};

/* Define table of divisors for moschip 7720 hardware      *
 * These assume a 3.6864MHz crystal, the standard /16, and *
 * MCR.7 = 0.                                              */
static struct divisor_table_entry divisor_table[] = {
        {   50,         2304},
        {   110,        1047},  /* 2094.545455 => 230450   => .0217 % over */
        {   134,        857},   /* 1713.011152 => 230398.5 => .00065% under */
        {   150,        768},
        {   300,        384},
        {   600,        192},
        {   1200,       96},
        {   1800,       64},
        {   2400,       48},
        {   4800,       24},
        {   7200,       16},
        {   9600,       12},
        {   19200,      6},
        {   38400,      3},
        {   57600,      2},
        {   115200,     1},
};

/*****************************************************************************
 * calc_baud_rate_divisor
 *      this function calculates the proper baud rate divisor for the specified
 *      baud rate.
 *****************************************************************************/
static int calc_baud_rate_divisor(int baudrate, int *divisor)
{
        int i;
        __u16 custom;
        __u16 round1;
        __u16 round;


        dbg("%s - %d", __func__, baudrate);

        for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
                if (divisor_table[i].baudrate == baudrate) {
                        *divisor = divisor_table[i].divisor;
                        return 0;
                }
        }

        /* After trying for all the standard baud rates    *
         * Try calculating the divisor for this baud rate  */
        if (baudrate > 75 &&  baudrate < 230400) {
                /* get the divisor */
                custom = (__u16)(230400L  / baudrate);

                /* Check for round off */
                round1 = (__u16)(2304000L / baudrate);
                round = (__u16)(round1 - (custom * 10));
                if (round > 4)
                        custom++;
                *divisor = custom;

                dbg("Baud %d = %d", baudrate, custom);
                return 0;
        }

        dbg("Baud calculation Failed...");
        return -EINVAL;
}

/*
 * send_cmd_write_baud_rate
 *      this function sends the proper command to change the baud rate of the
 *      specified port.
 */
static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
                                    int baudrate)
{
        struct usb_serial_port *port;
        struct usb_serial *serial;
        int divisor;
        int status;
        unsigned char data;
        unsigned char number;

        if (mos7720_port == NULL)
                return -1;

        port = mos7720_port->port;
        serial = port->serial;

        dbg("%s: Entering ..........", __func__);

        number = port->number - port->serial->minor;
        dbg("%s - port = %d, baud = %d", __func__, port->number, baudrate);

        /* Calculate the Divisor */
        status = calc_baud_rate_divisor(baudrate, &divisor);
        if (status) {
                dev_err(&port->dev, "%s - bad baud rate\n", __func__);
                return status;
        }

        /* Enable access to divisor latch */
        data = mos7720_port->shadowLCR | UART_LCR_DLAB;
        mos7720_port->shadowLCR  = data;
        send_mos_cmd(serial, MOS_WRITE, number, UART_LCR, &data);

        /* Write the divisor */
        data = ((unsigned char)(divisor & 0xff));
        send_mos_cmd(serial, MOS_WRITE, number, 0x00, &data);

        data = ((unsigned char)((divisor & 0xff00) >> 8));
        send_mos_cmd(serial, MOS_WRITE, number, 0x01, &data);

        /* Disable access to divisor latch */
        data = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
        mos7720_port->shadowLCR = data;
        send_mos_cmd(serial, MOS_WRITE, number, 0x03, &data);

        return status;
}

/*

 * change_port_settings
 *      This routine is called to set the UART on the device to match
 *      the specified new settings.
 */
static void change_port_settings(struct tty_struct *tty,
                                 struct moschip_port *mos7720_port,
                                 struct ktermios *old_termios)
{
        struct usb_serial_port *port;
        struct usb_serial *serial;
        int baud;
        unsigned cflag;
        unsigned iflag;
        __u8 mask = 0xff;
        __u8 lData;
        __u8 lParity;
        __u8 lStop;
        int status;
        int port_number;
        char data;

        if (mos7720_port == NULL)
                return ;

        port = mos7720_port->port;
        serial = port->serial;
        port_number = port->number - port->serial->minor;

        dbg("%s - port %d", __func__, port->number);

        if (!mos7720_port->open) {
                dbg("%s - port not opened", __func__);
                return;
        }

        dbg("%s: Entering ..........", __func__);

        lData = UART_LCR_WLEN8;
        lStop = 0x00;   /* 1 stop bit */
        lParity = 0x00; /* No parity */

        cflag = tty->termios->c_cflag;
        iflag = tty->termios->c_iflag;

        /* Change the number of bits */
        switch (cflag & CSIZE) {
        case CS5:
                lData = UART_LCR_WLEN5;
                mask = 0x1f;
                break;

        case CS6:
                lData = UART_LCR_WLEN6;
                mask = 0x3f;
                break;

        case CS7:
                lData = UART_LCR_WLEN7;
                mask = 0x7f;
                break;
        default:
        case CS8:
                lData = UART_LCR_WLEN8;
                break;
        }

        /* Change the Parity bit */
        if (cflag & PARENB) {
                if (cflag & PARODD) {
                        lParity = UART_LCR_PARITY;
                        dbg("%s - parity = odd", __func__);
                } else {
                        lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
                        dbg("%s - parity = even", __func__);
                }

        } else {
                dbg("%s - parity = none", __func__);
        }

        if (cflag & CMSPAR)
                lParity = lParity | 0x20;

        /* Change the Stop bit */
        if (cflag & CSTOPB) {
                lStop = UART_LCR_STOP;
                dbg("%s - stop bits = 2", __func__);
        } else {
                lStop = 0x00;
                dbg("%s - stop bits = 1", __func__);
        }

#define LCR_BITS_MASK           0x03    /* Mask for bits/char field */
#define LCR_STOP_MASK           0x04    /* Mask for stop bits field */
#define LCR_PAR_MASK            0x38    /* Mask for parity field */

        /* Update the LCR with the correct value */
        mos7720_port->shadowLCR &=
                        ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
        mos7720_port->shadowLCR |= (lData | lParity | lStop);


        /* Disable Interrupts */
        data = 0x00;
        send_mos_cmd(serial, MOS_WRITE, port->number - port->serial->minor,
                                                        UART_IER, &data);

        data = 0x00;
        send_mos_cmd(serial, MOS_WRITE, port_number, UART_FCR, &data);

        data = 0xcf;
        send_mos_cmd(serial, MOS_WRITE, port_number, UART_FCR, &data);

        /* Send the updated LCR value to the mos7720 */
        data = mos7720_port->shadowLCR;
        send_mos_cmd(serial, MOS_WRITE, port_number, UART_LCR, &data);

        data = 0x00b;
        mos7720_port->shadowMCR = data;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);
        data = 0x00b;
        send_mos_cmd(serial, MOS_WRITE, port_number, 0x04, &data);

        /* set up the MCR register and send it to the mos7720 */
        mos7720_port->shadowMCR = UART_MCR_OUT2;
        if (cflag & CBAUD)
                mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);

        if (cflag & CRTSCTS) {
                mos7720_port->shadowMCR |= (UART_MCR_XONANY);
                /* To set hardware flow control to the specified *
                 * serial port, in SP1/2_CONTROL_REG             */
                if (port->number) {
                        data = 0x001;
                        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT,
                                     0x08, &data);
                } else {
                        data = 0x002;
                        send_mos_cmd(serial, MOS_WRITE, MOS_MAX_PORT,
                                     0x08, &data);
                }
        } else {
                mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
        }

        data = mos7720_port->shadowMCR;
        send_mos_cmd(serial, MOS_WRITE, port_number, UART_MCR, &data);

        /* Determine divisor based on baud rate */
        baud = tty_get_baud_rate(tty);
        if (!baud) {
                /* pick a default, any default... */
                dbg("Picked default baud...");
                baud = 9600;
        }

        if (baud >= 230400) {
                set_higher_rates(mos7720_port, baud);
                /* Enable Interrupts */
                data = 0x0c;
                send_mos_cmd(serial, MOS_WRITE, port_number, UART_IER, &data);
                return;
        }

        dbg("%s - baud rate = %d", __func__, baud);
        status = send_cmd_write_baud_rate(mos7720_port, baud);
        /* FIXME: needs to write actual resulting baud back not just
           blindly do so */
        if (cflag & CBAUD)
                tty_encode_baud_rate(tty, baud, baud);
        /* Enable Interrupts */
        data = 0x0c;
        send_mos_cmd(serial, MOS_WRITE, port_number, UART_IER, &data);

        if (port->read_urb->status != -EINPROGRESS) {
                port->read_urb->dev = serial->dev;

                status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
                if (status)
                        dbg("usb_submit_urb(read bulk) failed, status = %d",
                            status);
        }
        return;
}

/*
 * mos7720_set_termios
 *      this function is called by the tty driver when it wants to change the
 *      termios structure.
 */
static void mos7720_set_termios(struct tty_struct *tty,
                struct usb_serial_port *port, struct ktermios *old_termios)
{
        int status;
        unsigned int cflag;
        struct usb_serial *serial;
        struct moschip_port *mos7720_port;

        serial = port->serial;

        mos7720_port = usb_get_serial_port_data(port);

        if (mos7720_port == NULL)
                return;

        if (!mos7720_port->open) {
                dbg("%s - port not opened", __func__);
                return;
        }

        dbg("%s\n", "setting termios - ASPIRE");

        cflag = tty->termios->c_cflag;

        dbg("%s - cflag %08x iflag %08x", __func__,
            tty->termios->c_cflag,
            RELEVANT_IFLAG(tty->termios->c_iflag));

        dbg("%s - old cflag %08x old iflag %08x", __func__,
            old_termios->c_cflag,
            RELEVANT_IFLAG(old_termios->c_iflag));

        dbg("%s - port %d", __func__, port->number);

        /* change the port settings to the new ones specified */
        change_port_settings(tty, mos7720_port, old_termios);

        if (!port->read_urb) {
                dbg("%s", "URB KILLED !!!!!\n");
                return;
        }

        if (port->read_urb->status != -EINPROGRESS) {
                port->read_urb->dev = serial->dev;
                status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
                if (status)
                        dbg("usb_submit_urb(read bulk) failed, status = %d",
                            status);
        }
        return;
}

/*
 * get_lsr_info - get line status register info
 *
 * Purpose: Let user call ioctl() to get info when the UART physically
 *          is emptied.  On bus types like RS485, the transmitter must
 *          release the bus after transmitting. This must be done when
 *          the transmit shift register is empty, not be done when the
 *          transmit holding register is empty.  This functionality
 *          allows an RS485 driver to be written in user space.
 */
static int get_lsr_info(struct tty_struct *tty,
                struct moschip_port *mos7720_port, unsigned int __user *value)
{
        struct usb_serial_port *port = tty->driver_data;
        unsigned int result = 0;
        unsigned char data = 0;
        int port_number = port->number - port->serial->minor;
        int count;

        count = mos7720_chars_in_buffer(tty);
        if (count == 0) {
                send_mos_cmd(port->serial, MOS_READ, port_number,
                                                        UART_LSR, &data);
                if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
                                        == (UART_LSR_TEMT | UART_LSR_THRE)) {
                        dbg("%s -- Empty", __func__);
                        result = TIOCSER_TEMT;
                }
        }
        if (copy_to_user(value, &result, sizeof(int)))
                return -EFAULT;
        return 0;
}

static int mos7720_tiocmget(struct tty_struct *tty, struct file *file)
{
        struct usb_serial_port *port = tty->driver_data;
        struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
        unsigned int result = 0;
        unsigned int mcr ;
        unsigned int msr ;

        dbg("%s - port %d", __func__, port->number);

        mcr = mos7720_port->shadowMCR;
        msr = mos7720_port->shadowMSR;

        result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
          | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
          | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
          | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
          | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
          | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */

        dbg("%s -- %x", __func__, result);

        return result;
}

static int mos7720_tiocmset(struct tty_struct *tty, struct file *file,
                                        unsigned int set, unsigned int clear)
{
        struct usb_serial_port *port = tty->driver_data;
        struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
        unsigned int mcr ;
        unsigned char lmcr;

        dbg("%s - port %d", __func__, port->number);
        dbg("he was at tiocmget");

        mcr = mos7720_port->shadowMCR;

        if (set & TIOCM_RTS)
                mcr |= UART_MCR_RTS;
        if (set & TIOCM_DTR)
                mcr |= UART_MCR_DTR;
        if (set & TIOCM_LOOP)
                mcr |= UART_MCR_LOOP;

        if (clear & TIOCM_RTS)
                mcr &= ~UART_MCR_RTS;
        if (clear & TIOCM_DTR)
                mcr &= ~UART_MCR_DTR;
        if (clear & TIOCM_LOOP)
                mcr &= ~UART_MCR_LOOP;

        mos7720_port->shadowMCR = mcr;
        lmcr = mos7720_port->shadowMCR;

        send_mos_cmd(port->serial, MOS_WRITE,
                port->number - port->serial->minor, UART_MCR, &lmcr);

        return 0;
}

static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
                          unsigned int __user *value)
{
        unsigned int mcr ;
        unsigned int arg;
        unsigned char data;

        struct usb_serial_port *port;

        if (mos7720_port == NULL)
                return -1;

        port = (struct usb_serial_port *)mos7720_port->port;
        mcr = mos7720_port->shadowMCR;

        if (copy_from_user(&arg, value, sizeof(int)))
                return -EFAULT;

        switch (cmd) {
        case TIOCMBIS:
                if (arg & TIOCM_RTS)
                        mcr |= UART_MCR_RTS;
                if (arg & TIOCM_DTR)
                        mcr |= UART_MCR_RTS;
                if (arg & TIOCM_LOOP)
                        mcr |= UART_MCR_LOOP;
                break;

        case TIOCMBIC:
                if (arg & TIOCM_RTS)
                        mcr &= ~UART_MCR_RTS;
                if (arg & TIOCM_DTR)
                        mcr &= ~UART_MCR_RTS;
                if (arg & TIOCM_LOOP)
                        mcr &= ~UART_MCR_LOOP;
                break;

        }

        mos7720_port->shadowMCR = mcr;

        data = mos7720_port->shadowMCR;
        send_mos_cmd(port->serial, MOS_WRITE,
                     port->number - port->serial->minor, UART_MCR, &data);

        return 0;
}

static int get_serial_info(struct moschip_port *mos7720_port,
                           struct serial_struct __user *retinfo)
{
        struct serial_struct tmp;

        if (!retinfo)
                return -EFAULT;

        memset(&tmp, 0, sizeof(tmp));

        tmp.type                = PORT_16550A;
        tmp.line                = mos7720_port->port->serial->minor;
        tmp.port                = mos7720_port->port->number;
        tmp.irq                 = 0;
        tmp.flags               = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
        tmp.xmit_fifo_size      = NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
        tmp.baud_base           = 9600;
        tmp.close_delay         = 5*HZ;
        tmp.closing_wait        = 30*HZ;

        if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
                return -EFAULT;
        return 0;
}

static int mos7720_ioctl(struct tty_struct *tty, struct file *file,
                         unsigned int cmd, unsigned long arg)
{
        struct usb_serial_port *port = tty->driver_data;
        struct moschip_port *mos7720_port;
        struct async_icount cnow;
        struct async_icount cprev;
        struct serial_icounter_struct icount;

        mos7720_port = usb_get_serial_port_data(port);
        if (mos7720_port == NULL)
                return -ENODEV;

        dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);

        switch (cmd) {
        case TIOCSERGETLSR:
                dbg("%s (%d) TIOCSERGETLSR", __func__,  port->number);
                return get_lsr_info(tty, mos7720_port,
                                        (unsigned int __user *)arg);
                return 0;

        /* FIXME: These should be using the mode methods */
        case TIOCMBIS:
        case TIOCMBIC:
                dbg("%s (%d) TIOCMSET/TIOCMBIC/TIOCMSET",
                                        __func__, port->number);
                return set_modem_info(mos7720_port, cmd,
                                      (unsigned int __user *)arg);

        case TIOCGSERIAL:
                dbg("%s (%d) TIOCGSERIAL", __func__,  port->number);
                return get_serial_info(mos7720_port,
                                       (struct serial_struct __user *)arg);

        case TIOCMIWAIT:
                dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
                cprev = mos7720_port->icount;
                while (1) {
                        if (signal_pending(current))
                                return -ERESTARTSYS;
                        cnow = mos7720_port->icount;
                        if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
                            cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
                                return -EIO; /* no change => error */
                        if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
                            ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
                            ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
                            ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
                                return 0;
                        }
                        cprev = cnow;
                }
                /* NOTREACHED */
                break;

        case TIOCGICOUNT:
                cnow = mos7720_port->icount;
                icount.cts = cnow.cts;
                icount.dsr = cnow.dsr;
                icount.rng = cnow.rng;
                icount.dcd = cnow.dcd;
                icount.rx = cnow.rx;
                icount.tx = cnow.tx;
                icount.frame = cnow.frame;
                icount.overrun = cnow.overrun;
                icount.parity = cnow.parity;
                icount.brk = cnow.brk;
                icount.buf_overrun = cnow.buf_overrun;

                dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __func__,
                    port->number, icount.rx, icount.tx);
                if (copy_to_user((void __user *)arg, &icount, sizeof(icount)))
                        return -EFAULT;
                return 0;
        }

        return -ENOIOCTLCMD;
}

static int mos7720_startup(struct usb_serial *serial)
{
        struct moschip_serial *mos7720_serial;
        struct moschip_port *mos7720_port;
        struct usb_device *dev;
        int i;
        char data;

        dbg("%s: Entering ..........", __func__);

        if (!serial) {
                dbg("Invalid Handler");
                return -ENODEV;
        }

        dev = serial->dev;

        /* create our private serial structure */
        mos7720_serial = kzalloc(sizeof(struct moschip_serial), GFP_KERNEL);
        if (mos7720_serial == NULL) {
                dev_err(&dev->dev, "%s - Out of memory\n", __func__);
                return -ENOMEM;
        }

        usb_set_serial_data(serial, mos7720_serial);

        /* we set up the pointers to the endpoints in the mos7720_open *
         * function, as the structures aren't created yet.             */

        /* set up port private structures */
        for (i = 0; i < serial->num_ports; ++i) {
                mos7720_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
                if (mos7720_port == NULL) {
                        dev_err(&dev->dev, "%s - Out of memory\n", __func__);
                        usb_set_serial_data(serial, NULL);
                        kfree(mos7720_serial);
                        return -ENOMEM;
                }

                /* Initialize all port interrupt end point to port 0 int
                 * endpoint.  Our device has only one interrupt endpoint
                 * comman to all ports */
                serial->port[i]->interrupt_in_endpointAddress =
                                serial->port[0]->interrupt_in_endpointAddress;

                mos7720_port->port = serial->port[i];
                usb_set_serial_port_data(serial->port[i], mos7720_port);

                dbg("port number is %d", serial->port[i]->number);
                dbg("serial number is %d", serial->minor);
        }


        /* setting configuration feature to one */
        usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
                        (__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5*HZ);

        /* LSR For Port 1 */
        send_mos_cmd(serial, MOS_READ, 0x00, UART_LSR, &data);
        dbg("LSR:%x", data);

        /* LSR For Port 2 */
        send_mos_cmd(serial, MOS_READ, 0x01, UART_LSR, &data);
        dbg("LSR:%x", data);

        return 0;
}

static void mos7720_release(struct usb_serial *serial)
{
        int i;

        /* free private structure allocated for serial port */
        for (i = 0; i < serial->num_ports; ++i)
                kfree(usb_get_serial_port_data(serial->port[i]));

        /* free private structure allocated for serial device */
        kfree(usb_get_serial_data(serial));
}

static struct usb_driver usb_driver = {
        .name =         "moschip7720",
        .probe =        usb_serial_probe,
        .disconnect =   usb_serial_disconnect,
        .id_table =     moschip_port_id_table,
        .no_dynamic_id =        1,
};

static struct usb_serial_driver moschip7720_2port_driver = {
        .driver = {
                .owner =        THIS_MODULE,
                .name =         "moschip7720",
        },
        .description            = "Moschip 2 port adapter",
        .usb_driver             = &usb_driver,
        .id_table               = moschip_port_id_table,
        .num_ports              = 2,
        .open                   = mos7720_open,
        .close                  = mos7720_close,
        .throttle               = mos7720_throttle,
        .unthrottle             = mos7720_unthrottle,
        .attach                 = mos7720_startup,
        .release                = mos7720_release,
        .ioctl                  = mos7720_ioctl,
        .tiocmget               = mos7720_tiocmget,
        .tiocmset               = mos7720_tiocmset,
        .set_termios            = mos7720_set_termios,
        .write                  = mos7720_write,
        .write_room             = mos7720_write_room,
        .chars_in_buffer        = mos7720_chars_in_buffer,
        .break_ctl              = mos7720_break,
        .read_bulk_callback     = mos7720_bulk_in_callback,
        .read_int_callback      = mos7720_interrupt_callback,
};

static int __init moschip7720_init(void)
{
        int retval;

        dbg("%s: Entering ..........", __func__);

        /* Register with the usb serial */
        retval = usb_serial_register(&moschip7720_2port_driver);
        if (retval)
                goto failed_port_device_register;

        printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
               DRIVER_DESC "\n");

        /* Register with the usb */
        retval = usb_register(&usb_driver);
        if (retval)
                goto failed_usb_register;

        return 0;

failed_usb_register:
        usb_serial_deregister(&moschip7720_2port_driver);

failed_port_device_register:
        return retval;
}

static void __exit moschip7720_exit(void)
{
        usb_deregister(&usb_driver);
        usb_serial_deregister(&moschip7720_2port_driver);
}

module_init(moschip7720_init);
module_exit(moschip7720_exit);

/* Module information */
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");