/*
 * Edgeport USB Serial Converter driver
 *
 * Copyright (C) 2000 Inside Out Networks, All rights reserved.
 * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
 *
 *      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; either version 2 of the License, or
 *      (at your option) any later version.
 *
 * Supports the following devices:
 *      Edgeport/4
 *      Edgeport/4t
 *      Edgeport/2
 *      Edgeport/4i
 *      Edgeport/2i
 *      Edgeport/421
 *      Edgeport/21
 *      Rapidport/4
 *      Edgeport/8
 *      Edgeport/2D8
 *      Edgeport/4D8
 *      Edgeport/8i
 *
 * For questions or problems with this driver, contact Inside Out
 * Networks technical support, or Peter Berger <pberger@brimson.com>,
 * or Al Borchers <alborchers@steinerpoint.com>.
 *
 */

#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/errno.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/ioctl.h>
#include <linux/wait.h>
#include <linux/firmware.h>
#include <linux/ihex.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "io_edgeport.h"
#include "io_ionsp.h"           /* info for the iosp messages */
#include "io_16654.h"           /* 16654 UART defines */

#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com> and David Iacovelli"
#define DRIVER_DESC "Edgeport USB Serial Driver"

#define MAX_NAME_LEN            64

#define OPEN_TIMEOUT            (5*HZ)          /* 5 seconds */

/* receive port state */
enum RXSTATE {
        EXPECT_HDR1 = 0,    /* Expect header byte 1 */
        EXPECT_HDR2 = 1,    /* Expect header byte 2 */
        EXPECT_DATA = 2,    /* Expect 'RxBytesRemaining' data */
        EXPECT_HDR3 = 3,    /* Expect header byte 3 (for status hdrs only) */
};


/* Transmit Fifo
 * This Transmit queue is an extension of the edgeport Rx buffer.
 * The maximum amount of data buffered in both the edgeport
 * Rx buffer (maxTxCredits) and this buffer will never exceed maxTxCredits.
 */
struct TxFifo {
        unsigned int    head;   /* index to head pointer (write) */
        unsigned int    tail;   /* index to tail pointer (read)  */
        unsigned int    count;  /* Bytes in queue */
        unsigned int    size;   /* Max size of queue (equal to Max number of TxCredits) */
        unsigned char   *fifo;  /* allocated Buffer */
};

/* This structure holds all of the local port information */
struct edgeport_port {
        __u16                   txCredits;              /* our current credits for this port */
        __u16                   maxTxCredits;           /* the max size of the port */

        struct TxFifo           txfifo;                 /* transmit fifo -- size will be maxTxCredits */
        struct urb              *write_urb;             /* write URB for this port */
        bool                    write_in_progress;      /* 'true' while a write URB is outstanding */
        spinlock_t              ep_lock;

        __u8                    shadowLCR;              /* last LCR value received */
        __u8                    shadowMCR;              /* last MCR value received */
        __u8                    shadowMSR;              /* last MSR value received */
        __u8                    shadowLSR;              /* last LSR value received */
        __u8                    shadowXonChar;          /* last value set as XON char in Edgeport */
        __u8                    shadowXoffChar;         /* last value set as XOFF char in Edgeport */
        __u8                    validDataMask;
        __u32                   baudRate;

        bool                    open;
        bool                    openPending;
        bool                    commandPending;
        bool                    closePending;
        bool                    chaseResponsePending;

        wait_queue_head_t       wait_chase;             /* for handling sleeping while waiting for chase to finish */
        wait_queue_head_t       wait_open;              /* for handling sleeping while waiting for open to finish */
        wait_queue_head_t       wait_command;           /* for handling sleeping while waiting for command to finish */

        struct usb_serial_port  *port;                  /* loop back to the owner of this object */
};


/* This structure holds all of the individual device information */
struct edgeport_serial {
        char                    name[MAX_NAME_LEN+2];           /* string name of this device */

        struct edge_manuf_descriptor    manuf_descriptor;       /* the manufacturer descriptor */
        struct edge_boot_descriptor     boot_descriptor;        /* the boot firmware descriptor */
        struct edgeport_product_info    product_info;           /* Product Info */
        struct edge_compatibility_descriptor epic_descriptor;   /* Edgeport compatible descriptor */
        int                     is_epic;                        /* flag if EPiC device or not */

        __u8                    interrupt_in_endpoint;          /* the interrupt endpoint handle */
        unsigned char           *interrupt_in_buffer;           /* the buffer we use for the interrupt endpoint */
        struct urb              *interrupt_read_urb;            /* our interrupt urb */

        __u8                    bulk_in_endpoint;               /* the bulk in endpoint handle */
        unsigned char           *bulk_in_buffer;                /* the buffer we use for the bulk in endpoint */
        struct urb              *read_urb;                      /* our bulk read urb */
        bool                    read_in_progress;
        spinlock_t              es_lock;

        __u8                    bulk_out_endpoint;              /* the bulk out endpoint handle */

        __s16                   rxBytesAvail;                   /* the number of bytes that we need to read from this device */

        enum RXSTATE            rxState;                        /* the current state of the bulk receive processor */
        __u8                    rxHeader1;                      /* receive header byte 1 */
        __u8                    rxHeader2;                      /* receive header byte 2 */
        __u8                    rxHeader3;                      /* receive header byte 3 */
        __u8                    rxPort;                         /* the port that we are currently receiving data for */
        __u8                    rxStatusCode;                   /* the receive status code */
        __u8                    rxStatusParam;                  /* the receive status paramater */
        __s16                   rxBytesRemaining;               /* the number of port bytes left to read */
        struct usb_serial       *serial;                        /* loop back to the owner of this object */
};

/* baud rate information */
struct divisor_table_entry {
        __u32   BaudRate;
        __u16  Divisor;
};

/*
 * Define table of divisors for Rev A EdgePort/4 hardware
 * These assume a 3.6864MHz crystal, the standard /16, and
 * MCR.7 = 0.
 */

static const struct divisor_table_entry divisor_table[] = {
        {   50,         4608},
        {   75,         3072},
        {   110,        2095},  /* 2094.545455 => 230450   => .0217 % over */
        {   134,        1713},  /* 1713.011152 => 230398.5 => .00065% under */
        {   150,        1536},
        {   300,        768},
        {   600,        384},
        {   1200,       192},
        {   1800,       128},
        {   2400,       96},
        {   4800,       48},
        {   7200,       32},
        {   9600,       24},
        {   14400,      16},
        {   19200,      12},
        {   38400,      6},
        {   57600,      4},
        {   115200,     2},
        {   230400,     1},
};

/* Number of outstanding Command Write Urbs */
static atomic_t CmdUrbs = ATOMIC_INIT(0);


/* local function prototypes */

/* function prototypes for all URB callbacks */
static void edge_interrupt_callback(struct urb *urb);
static void edge_bulk_in_callback(struct urb *urb);
static void edge_bulk_out_data_callback(struct urb *urb);
static void edge_bulk_out_cmd_callback(struct urb *urb);

/* function prototypes for the usbserial callbacks */
static int edge_open(struct tty_struct *tty, struct usb_serial_port *port);
static void edge_close(struct usb_serial_port *port);
static int edge_write(struct tty_struct *tty, struct usb_serial_port *port,
                                        const unsigned char *buf, int count);
static int edge_write_room(struct tty_struct *tty);
static int edge_chars_in_buffer(struct tty_struct *tty);
static void edge_throttle(struct tty_struct *tty);
static void edge_unthrottle(struct tty_struct *tty);
static void edge_set_termios(struct tty_struct *tty,
                                        struct usb_serial_port *port,
                                        struct ktermios *old_termios);
static int  edge_ioctl(struct tty_struct *tty,
                                        unsigned int cmd, unsigned long arg);
static void edge_break(struct tty_struct *tty, int break_state);
static int  edge_tiocmget(struct tty_struct *tty);
static int  edge_tiocmset(struct tty_struct *tty,
                                        unsigned int set, unsigned int clear);
static int  edge_startup(struct usb_serial *serial);
static void edge_disconnect(struct usb_serial *serial);
static void edge_release(struct usb_serial *serial);
static int edge_port_probe(struct usb_serial_port *port);
static int edge_port_remove(struct usb_serial_port *port);

#include "io_tables.h"  /* all of the devices that this driver supports */

/* function prototypes for all of our local functions */

static void  process_rcvd_data(struct edgeport_serial *edge_serial,
                                unsigned char *buffer, __u16 bufferLength);
static void process_rcvd_status(struct edgeport_serial *edge_serial,
                                __u8 byte2, __u8 byte3);
static void edge_tty_recv(struct usb_serial_port *port, unsigned char *data,
                int length);
static void handle_new_msr(struct edgeport_port *edge_port, __u8 newMsr);
static void handle_new_lsr(struct edgeport_port *edge_port, __u8 lsrData,
                                __u8 lsr, __u8 data);
static int  send_iosp_ext_cmd(struct edgeport_port *edge_port, __u8 command,
                                __u8 param);
static int  calc_baud_rate_divisor(struct device *dev, int baud_rate, int *divisor);
static int  send_cmd_write_baud_rate(struct edgeport_port *edge_port,
                                int baudRate);
static void change_port_settings(struct tty_struct *tty,
                                struct edgeport_port *edge_port,
                                struct ktermios *old_termios);
static int  send_cmd_write_uart_register(struct edgeport_port *edge_port,
                                __u8 regNum, __u8 regValue);
static int  write_cmd_usb(struct edgeport_port *edge_port,
                                unsigned char *buffer, int writeLength);
static void send_more_port_data(struct edgeport_serial *edge_serial,
                                struct edgeport_port *edge_port);

static int sram_write(struct usb_serial *serial, __u16 extAddr, __u16 addr,
                                        __u16 length, const __u8 *data);
static int rom_read(struct usb_serial *serial, __u16 extAddr, __u16 addr,
                                                __u16 length, __u8 *data);
static int rom_write(struct usb_serial *serial, __u16 extAddr, __u16 addr,
                                        __u16 length, const __u8 *data);
static void get_manufacturing_desc(struct edgeport_serial *edge_serial);
static void get_boot_desc(struct edgeport_serial *edge_serial);
static void load_application_firmware(struct edgeport_serial *edge_serial);

static void unicode_to_ascii(char *string, int buflen,
                                __le16 *unicode, int unicode_size);


/* ************************************************************************ */
/* ************************************************************************ */
/* ************************************************************************ */
/* ************************************************************************ */

/************************************************************************
 *                                                                      *
 * update_edgeport_E2PROM()     Compare current versions of             *
 *                              Boot ROM and Manufacture                *
 *                              Descriptors with versions               *
 *                              embedded in this driver                 *
 *                                                                      *
 ************************************************************************/
static void update_edgeport_E2PROM(struct edgeport_serial *edge_serial)
{
        struct device *dev = &edge_serial->serial->dev->dev;
        __u32 BootCurVer;
        __u32 BootNewVer;
        __u8 BootMajorVersion;
        __u8 BootMinorVersion;
        __u16 BootBuildNumber;
        __u32 Bootaddr;
        const struct ihex_binrec *rec;
        const struct firmware *fw;
        const char *fw_name;
        int response;

        switch (edge_serial->product_info.iDownloadFile) {
        case EDGE_DOWNLOAD_FILE_I930:
                fw_name = "edgeport/boot.fw";
                break;
        case EDGE_DOWNLOAD_FILE_80251:
                fw_name = "edgeport/boot2.fw";
                break;
        default:
                return;
        }

        response = request_ihex_firmware(&fw, fw_name,
                                         &edge_serial->serial->dev->dev);
        if (response) {
                dev_err(dev, "Failed to load image \"%s\" err %d\n",
                       fw_name, response);
                return;
        }

        rec = (const struct ihex_binrec *)fw->data;
        BootMajorVersion = rec->data[0];
        BootMinorVersion = rec->data[1];
        BootBuildNumber = (rec->data[2] << 8) | rec->data[3];

        /* Check Boot Image Version */
        BootCurVer = (edge_serial->boot_descriptor.MajorVersion << 24) +
                     (edge_serial->boot_descriptor.MinorVersion << 16) +
                      le16_to_cpu(edge_serial->boot_descriptor.BuildNumber);

        BootNewVer = (BootMajorVersion << 24) +
                     (BootMinorVersion << 16) +
                      BootBuildNumber;

        dev_dbg(dev, "Current Boot Image version %d.%d.%d\n",
            edge_serial->boot_descriptor.MajorVersion,
            edge_serial->boot_descriptor.MinorVersion,
            le16_to_cpu(edge_serial->boot_descriptor.BuildNumber));


        if (BootNewVer > BootCurVer) {
                dev_dbg(dev, "**Update Boot Image from %d.%d.%d to %d.%d.%d\n",
                    edge_serial->boot_descriptor.MajorVersion,
                    edge_serial->boot_descriptor.MinorVersion,
                    le16_to_cpu(edge_serial->boot_descriptor.BuildNumber),
                    BootMajorVersion, BootMinorVersion, BootBuildNumber);

                dev_dbg(dev, "Downloading new Boot Image\n");

                for (rec = ihex_next_binrec(rec); rec;
                     rec = ihex_next_binrec(rec)) {
                        Bootaddr = be32_to_cpu(rec->addr);
                        response = rom_write(edge_serial->serial,
                                             Bootaddr >> 16,
                                             Bootaddr & 0xFFFF,
                                             be16_to_cpu(rec->len),
                                             &rec->data[0]);
                        if (response < 0) {
                                dev_err(&edge_serial->serial->dev->dev,
                                        "rom_write failed (%x, %x, %d)\n",
                                        Bootaddr >> 16, Bootaddr & 0xFFFF,
                                        be16_to_cpu(rec->len));
                                break;
                        }
                }
        } else {
                dev_dbg(dev, "Boot Image -- already up to date\n");
        }
        release_firmware(fw);
}

#if 0
/************************************************************************
 *
 *  Get string descriptor from device
 *
 ************************************************************************/
static int get_string_desc(struct usb_device *dev, int Id,
                                struct usb_string_descriptor **pRetDesc)
{
        struct usb_string_descriptor StringDesc;
        struct usb_string_descriptor *pStringDesc;

        dev_dbg(&dev->dev, "%s - USB String ID = %d\n", __func__, Id);

        if (!usb_get_descriptor(dev, USB_DT_STRING, Id, &StringDesc,
                                                sizeof(StringDesc)))
                return 0;

        pStringDesc = kmalloc(StringDesc.bLength, GFP_KERNEL);
        if (!pStringDesc)
                return -1;

        if (!usb_get_descriptor(dev, USB_DT_STRING, Id, pStringDesc,
                                                        StringDesc.bLength)) {
                kfree(pStringDesc);
                return -1;
        }

        *pRetDesc = pStringDesc;
        return 0;
}
#endif

static void dump_product_info(struct edgeport_serial *edge_serial,
                              struct edgeport_product_info *product_info)
{
        struct device *dev = &edge_serial->serial->dev->dev;

        /* Dump Product Info structure */
        dev_dbg(dev, "**Product Information:\n");
        dev_dbg(dev, "  ProductId             %x\n", product_info->ProductId);
        dev_dbg(dev, "  NumPorts              %d\n", product_info->NumPorts);
        dev_dbg(dev, "  ProdInfoVer           %d\n", product_info->ProdInfoVer);
        dev_dbg(dev, "  IsServer              %d\n", product_info->IsServer);
        dev_dbg(dev, "  IsRS232               %d\n", product_info->IsRS232);
        dev_dbg(dev, "  IsRS422               %d\n", product_info->IsRS422);
        dev_dbg(dev, "  IsRS485               %d\n", product_info->IsRS485);
        dev_dbg(dev, "  RomSize               %d\n", product_info->RomSize);
        dev_dbg(dev, "  RamSize               %d\n", product_info->RamSize);
        dev_dbg(dev, "  CpuRev                %x\n", product_info->CpuRev);
        dev_dbg(dev, "  BoardRev              %x\n", product_info->BoardRev);
        dev_dbg(dev, "  BootMajorVersion      %d.%d.%d\n",
                product_info->BootMajorVersion,
                product_info->BootMinorVersion,
                le16_to_cpu(product_info->BootBuildNumber));
        dev_dbg(dev, "  FirmwareMajorVersion  %d.%d.%d\n",
                product_info->FirmwareMajorVersion,
                product_info->FirmwareMinorVersion,
                le16_to_cpu(product_info->FirmwareBuildNumber));
        dev_dbg(dev, "  ManufactureDescDate   %d/%d/%d\n",
                product_info->ManufactureDescDate[0],
                product_info->ManufactureDescDate[1],
                product_info->ManufactureDescDate[2]+1900);
        dev_dbg(dev, "  iDownloadFile         0x%x\n",
                product_info->iDownloadFile);
        dev_dbg(dev, "  EpicVer               %d\n", product_info->EpicVer);
}

static void get_product_info(struct edgeport_serial *edge_serial)
{
        struct edgeport_product_info *product_info = &edge_serial->product_info;

        memset(product_info, 0, sizeof(struct edgeport_product_info));

        product_info->ProductId = (__u16)(le16_to_cpu(edge_serial->serial->dev->descriptor.idProduct) & ~ION_DEVICE_ID_80251_NETCHIP);
        product_info->NumPorts = edge_serial->manuf_descriptor.NumPorts;
        product_info->ProdInfoVer = 0;

        product_info->RomSize = edge_serial->manuf_descriptor.RomSize;
        product_info->RamSize = edge_serial->manuf_descriptor.RamSize;
        product_info->CpuRev = edge_serial->manuf_descriptor.CpuRev;
        product_info->BoardRev = edge_serial->manuf_descriptor.BoardRev;

        product_info->BootMajorVersion =
                                edge_serial->boot_descriptor.MajorVersion;
        product_info->BootMinorVersion =
                                edge_serial->boot_descriptor.MinorVersion;
        product_info->BootBuildNumber =
                                edge_serial->boot_descriptor.BuildNumber;

        memcpy(product_info->ManufactureDescDate,
                        edge_serial->manuf_descriptor.DescDate,
                        sizeof(edge_serial->manuf_descriptor.DescDate));

        /* check if this is 2nd generation hardware */
        if (le16_to_cpu(edge_serial->serial->dev->descriptor.idProduct)
                                            & ION_DEVICE_ID_80251_NETCHIP)
                product_info->iDownloadFile = EDGE_DOWNLOAD_FILE_80251;
        else
                product_info->iDownloadFile = EDGE_DOWNLOAD_FILE_I930;

        /* Determine Product type and set appropriate flags */
        switch (DEVICE_ID_FROM_USB_PRODUCT_ID(product_info->ProductId)) {
        case ION_DEVICE_ID_EDGEPORT_COMPATIBLE:
        case ION_DEVICE_ID_EDGEPORT_4T:
        case ION_DEVICE_ID_EDGEPORT_4:
        case ION_DEVICE_ID_EDGEPORT_2:
        case ION_DEVICE_ID_EDGEPORT_8_DUAL_CPU:
        case ION_DEVICE_ID_EDGEPORT_8:
        case ION_DEVICE_ID_EDGEPORT_421:
        case ION_DEVICE_ID_EDGEPORT_21:
        case ION_DEVICE_ID_EDGEPORT_2_DIN:
        case ION_DEVICE_ID_EDGEPORT_4_DIN:
        case ION_DEVICE_ID_EDGEPORT_16_DUAL_CPU:
                product_info->IsRS232 = 1;
                break;

        case ION_DEVICE_ID_EDGEPORT_2I: /* Edgeport/2 RS422/RS485 */
                product_info->IsRS422 = 1;
                product_info->IsRS485 = 1;
                break;

        case ION_DEVICE_ID_EDGEPORT_8I: /* Edgeport/4 RS422 */
        case ION_DEVICE_ID_EDGEPORT_4I: /* Edgeport/4 RS422 */
                product_info->IsRS422 = 1;
                break;
        }

        dump_product_info(edge_serial, product_info);
}

static int get_epic_descriptor(struct edgeport_serial *ep)
{
        int result;
        struct usb_serial *serial = ep->serial;
        struct edgeport_product_info *product_info = &ep->product_info;
        struct edge_compatibility_descriptor *epic = &ep->epic_descriptor;
        struct edge_compatibility_bits *bits;
        struct device *dev = &serial->dev->dev;

        ep->is_epic = 0;
        result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
                                 USB_REQUEST_ION_GET_EPIC_DESC,
                                 0xC0, 0x00, 0x00,
                                 &ep->epic_descriptor,
                                 sizeof(struct edge_compatibility_descriptor),
                                 300);

        if (result > 0) {
                ep->is_epic = 1;
                memset(product_info, 0, sizeof(struct edgeport_product_info));

                product_info->NumPorts = epic->NumPorts;
                product_info->ProdInfoVer = 0;
                product_info->FirmwareMajorVersion = epic->MajorVersion;
                product_info->FirmwareMinorVersion = epic->MinorVersion;
                product_info->FirmwareBuildNumber = epic->BuildNumber;
                product_info->iDownloadFile = epic->iDownloadFile;
                product_info->EpicVer = epic->EpicVer;
                product_info->Epic = epic->Supports;
                product_info->ProductId = ION_DEVICE_ID_EDGEPORT_COMPATIBLE;
                dump_product_info(ep, product_info);

                bits = &ep->epic_descriptor.Supports;
                dev_dbg(dev, "**EPIC descriptor:\n");
                dev_dbg(dev, "  VendEnableSuspend: %s\n", bits->VendEnableSuspend ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPOpen         : %s\n", bits->IOSPOpen        ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPClose        : %s\n", bits->IOSPClose       ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPChase        : %s\n", bits->IOSPChase       ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPSetRxFlow    : %s\n", bits->IOSPSetRxFlow   ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPSetTxFlow    : %s\n", bits->IOSPSetTxFlow   ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPSetXChar     : %s\n", bits->IOSPSetXChar    ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPRxCheck      : %s\n", bits->IOSPRxCheck     ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPSetClrBreak  : %s\n", bits->IOSPSetClrBreak ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPWriteMCR     : %s\n", bits->IOSPWriteMCR    ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPWriteLCR     : %s\n", bits->IOSPWriteLCR    ? "TRUE": "FALSE");
                dev_dbg(dev, "  IOSPSetBaudRate  : %s\n", bits->IOSPSetBaudRate ? "TRUE": "FALSE");
                dev_dbg(dev, "  TrueEdgeport     : %s\n", bits->TrueEdgeport    ? "TRUE": "FALSE");
        }

        return result;
}


/************************************************************************/
/************************************************************************/
/*            U S B  C A L L B A C K   F U N C T I O N S                */
/*            U S B  C A L L B A C K   F U N C T I O N S                */
/************************************************************************/
/************************************************************************/

/*****************************************************************************
 * edge_interrupt_callback
 *      this is the callback function for when we have received data on the
 *      interrupt endpoint.
 *****************************************************************************/
static void edge_interrupt_callback(struct urb *urb)
{
        struct edgeport_serial *edge_serial = urb->context;
        struct device *dev;
        struct edgeport_port *edge_port;
        struct usb_serial_port *port;
        unsigned char *data = urb->transfer_buffer;
        int length = urb->actual_length;
        int bytes_avail;
        int position;
        int txCredits;
        int portNumber;
        int result;
        int status = urb->status;

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

        dev = &edge_serial->serial->dev->dev;

        /* process this interrupt-read even if there are no ports open */
        if (length) {
                usb_serial_debug_data(dev, __func__, length, data);

                if (length > 1) {
                        bytes_avail = data[0] | (data[1] << 8);
                        if (bytes_avail) {
                                spin_lock(&edge_serial->es_lock);
                                edge_serial->rxBytesAvail += bytes_avail;
                                dev_dbg(dev,
                                        "%s - bytes_avail=%d, rxBytesAvail=%d, read_in_progress=%d\n",
                                        __func__, bytes_avail,
                                        edge_serial->rxBytesAvail,
                                        edge_serial->read_in_progress);

                                if (edge_serial->rxBytesAvail > 0 &&
                                    !edge_serial->read_in_progress) {
                                        dev_dbg(dev, "%s - posting a read\n", __func__);
                                        edge_serial->read_in_progress = true;

                                        /* we have pending bytes on the
                                           bulk in pipe, send a request */
                                        result = usb_submit_urb(edge_serial->read_urb, GFP_ATOMIC);
                                        if (result) {
                                                dev_err(dev,
                                                        "%s - usb_submit_urb(read bulk) failed with result = %d\n",
                                                        __func__, result);
                                                edge_serial->read_in_progress = false;
                                        }
                                }
                                spin_unlock(&edge_serial->es_lock);
                        }
                }
                /* grab the txcredits for the ports if available */
                position = 2;
                portNumber = 0;
                while ((position < length) &&
                                (portNumber < edge_serial->serial->num_ports)) {
                        txCredits = data[position] | (data[position+1] << 8);
                        if (txCredits) {
                                port = edge_serial->serial->port[portNumber];
                                edge_port = usb_get_serial_port_data(port);
                                if (edge_port->open) {
                                        spin_lock(&edge_port->ep_lock);
                                        edge_port->txCredits += txCredits;
                                        spin_unlock(&edge_port->ep_lock);
                                        dev_dbg(dev, "%s - txcredits for port%d = %d\n",
                                                __func__, portNumber,
                                                edge_port->txCredits);

                                        /* tell the tty driver that something
                                           has changed */
                                        tty_port_tty_wakeup(&edge_port->port->port);
                                        /* Since we have more credit, check
                                           if more data can be sent */
                                        send_more_port_data(edge_serial,
                                                                edge_port);
                                }
                        }
                        position += 2;
                        ++portNumber;
                }
        }

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


/*****************************************************************************
 * edge_bulk_in_callback
 *      this is the callback function for when we have received data on the
 *      bulk in endpoint.
 *****************************************************************************/
static void edge_bulk_in_callback(struct urb *urb)
{
        struct edgeport_serial  *edge_serial = urb->context;
        struct device *dev;
        unsigned char           *data = urb->transfer_buffer;
        int                     retval;
        __u16                   raw_data_length;
        int status = urb->status;

        if (status) {
                dev_dbg(&urb->dev->dev, "%s - nonzero read bulk status received: %d\n",
                        __func__, status);
                edge_serial->read_in_progress = false;
                return;
        }

        if (urb->actual_length == 0) {
                dev_dbg(&urb->dev->dev, "%s - read bulk callback with no data\n", __func__);
                edge_serial->read_in_progress = false;
                return;
        }

        dev = &edge_serial->serial->dev->dev;
        raw_data_length = urb->actual_length;

        usb_serial_debug_data(dev, __func__, raw_data_length, data);

        spin_lock(&edge_serial->es_lock);

        /* decrement our rxBytes available by the number that we just got */
        edge_serial->rxBytesAvail -= raw_data_length;

        dev_dbg(dev, "%s - Received = %d, rxBytesAvail %d\n", __func__,
                raw_data_length, edge_serial->rxBytesAvail);

        process_rcvd_data(edge_serial, data, urb->actual_length);

        /* check to see if there's any more data for us to read */
        if (edge_serial->rxBytesAvail > 0) {
                dev_dbg(dev, "%s - posting a read\n", __func__);
                retval = usb_submit_urb(edge_serial->read_urb, GFP_ATOMIC);
                if (retval) {
                        dev_err(dev,
                                "%s - usb_submit_urb(read bulk) failed, retval = %d\n",
                                __func__, retval);
                        edge_serial->read_in_progress = false;
                }
        } else {
                edge_serial->read_in_progress = false;
        }

        spin_unlock(&edge_serial->es_lock);
}


/*****************************************************************************
 * edge_bulk_out_data_callback
 *      this is the callback function for when we have finished sending
 *      serial data on the bulk out endpoint.
 *****************************************************************************/
static void edge_bulk_out_data_callback(struct urb *urb)
{
        struct edgeport_port *edge_port = urb->context;
        int status = urb->status;

        if (status) {
                dev_dbg(&urb->dev->dev,
                        "%s - nonzero write bulk status received: %d\n",
                        __func__, status);
        }

        if (edge_port->open)
                tty_port_tty_wakeup(&edge_port->port->port);

        /* Release the Write URB */
        edge_port->write_in_progress = false;

        /* Check if more data needs to be sent */
        send_more_port_data((struct edgeport_serial *)
                (usb_get_serial_data(edge_port->port->serial)), edge_port);
}


/*****************************************************************************
 * BulkOutCmdCallback
 *      this is the callback function for when we have finished sending a
 *      command on the bulk out endpoint.
 *****************************************************************************/
static void edge_bulk_out_cmd_callback(struct urb *urb)
{
        struct edgeport_port *edge_port = urb->context;
        int status = urb->status;

        atomic_dec(&CmdUrbs);
        dev_dbg(&urb->dev->dev, "%s - FREE URB %p (outstanding %d)\n",
                __func__, urb, atomic_read(&CmdUrbs));


        /* clean up the transfer buffer */
        kfree(urb->transfer_buffer);

        /* Free the command urb */
        usb_free_urb(urb);

        if (status) {
                dev_dbg(&urb->dev->dev,
                        "%s - nonzero write bulk status received: %d\n",
                        __func__, status);
                return;
        }

        /* tell the tty driver that something has changed */
        if (edge_port->open)
                tty_port_tty_wakeup(&edge_port->port->port);

        /* we have completed the command */
        edge_port->commandPending = false;
        wake_up(&edge_port->wait_command);
}


/*****************************************************************************
 * Driver tty interface functions
 *****************************************************************************/

/*****************************************************************************
 * SerialOpen
 *      this function is called by the tty driver when a port is opened
 *      If successful, we return 0
 *      Otherwise we return a negative error number.
 *****************************************************************************/
static int edge_open(struct tty_struct *tty, struct usb_serial_port *port)
{
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        struct device *dev = &port->dev;
        struct usb_serial *serial;
        struct edgeport_serial *edge_serial;
        int response;

        if (edge_port == NULL)
                return -ENODEV;

        /* see if we've set up our endpoint info yet (can't set it up
           in edge_startup as the structures were not set up at that time.) */
        serial = port->serial;
        edge_serial = usb_get_serial_data(serial);
        if (edge_serial == NULL)
                return -ENODEV;
        if (edge_serial->interrupt_in_buffer == NULL) {
                struct usb_serial_port *port0 = serial->port[0];

                /* not set up yet, so do it now */
                edge_serial->interrupt_in_buffer =
                                        port0->interrupt_in_buffer;
                edge_serial->interrupt_in_endpoint =
                                        port0->interrupt_in_endpointAddress;
                edge_serial->interrupt_read_urb = port0->interrupt_in_urb;
                edge_serial->bulk_in_buffer = port0->bulk_in_buffer;
                edge_serial->bulk_in_endpoint =
                                        port0->bulk_in_endpointAddress;
                edge_serial->read_urb = port0->read_urb;
                edge_serial->bulk_out_endpoint =
                                        port0->bulk_out_endpointAddress;

                /* set up our interrupt urb */
                usb_fill_int_urb(edge_serial->interrupt_read_urb,
                      serial->dev,
                      usb_rcvintpipe(serial->dev,
                                port0->interrupt_in_endpointAddress),
                      port0->interrupt_in_buffer,
                      edge_serial->interrupt_read_urb->transfer_buffer_length,
                      edge_interrupt_callback, edge_serial,
                      edge_serial->interrupt_read_urb->interval);

                /* set up our bulk in urb */
                usb_fill_bulk_urb(edge_serial->read_urb, serial->dev,
                        usb_rcvbulkpipe(serial->dev,
                                port0->bulk_in_endpointAddress),
                        port0->bulk_in_buffer,
                        edge_serial->read_urb->transfer_buffer_length,
                        edge_bulk_in_callback, edge_serial);
                edge_serial->read_in_progress = false;

                /* start interrupt read for this edgeport
                 * this interrupt will continue as long
                 * as the edgeport is connected */
                response = usb_submit_urb(edge_serial->interrupt_read_urb,
                                                                GFP_KERNEL);
                if (response) {
                        dev_err(dev, "%s - Error %d submitting control urb\n",
                                __func__, response);
                }
        }

        /* initialize our wait queues */
        init_waitqueue_head(&edge_port->wait_open);
        init_waitqueue_head(&edge_port->wait_chase);
        init_waitqueue_head(&edge_port->wait_command);

        /* initialize our port settings */
        edge_port->txCredits = 0;       /* Can't send any data yet */
        /* Must always set this bit to enable ints! */
        edge_port->shadowMCR = MCR_MASTER_IE;
        edge_port->chaseResponsePending = false;

        /* send a open port command */
        edge_port->openPending = true;
        edge_port->open        = false;
        response = send_iosp_ext_cmd(edge_port, IOSP_CMD_OPEN_PORT, 0);

        if (response < 0) {
                dev_err(dev, "%s - error sending open port command\n", __func__);
                edge_port->openPending = false;
                return -ENODEV;
        }

        /* now wait for the port to be completely opened */
        wait_event_timeout(edge_port->wait_open, !edge_port->openPending,
                                                                OPEN_TIMEOUT);

        if (!edge_port->open) {
                /* open timed out */
                dev_dbg(dev, "%s - open timedout\n", __func__);
                edge_port->openPending = false;
                return -ENODEV;
        }

        /* create the txfifo */
        edge_port->txfifo.head  = 0;
        edge_port->txfifo.tail  = 0;
        edge_port->txfifo.count = 0;
        edge_port->txfifo.size  = edge_port->maxTxCredits;
        edge_port->txfifo.fifo  = kmalloc(edge_port->maxTxCredits, GFP_KERNEL);

        if (!edge_port->txfifo.fifo) {
                edge_close(port);
                return -ENOMEM;
        }

        /* Allocate a URB for the write */
        edge_port->write_urb = usb_alloc_urb(0, GFP_KERNEL);
        edge_port->write_in_progress = false;

        if (!edge_port->write_urb) {
                edge_close(port);
                return -ENOMEM;
        }

        dev_dbg(dev, "%s - Initialize TX fifo to %d bytes\n",
                __func__, edge_port->maxTxCredits);

        return 0;
}


/************************************************************************
 *
 * block_until_chase_response
 *
 *      This function will block the close until one of the following:
 *              1. Response to our Chase comes from Edgeport
 *              2. A timeout of 10 seconds without activity has expired
 *                 (1K of Edgeport data @ 2400 baud ==> 4 sec to empty)
 *
 ************************************************************************/
static void block_until_chase_response(struct edgeport_port *edge_port)
{
        struct device *dev = &edge_port->port->dev;
        DEFINE_WAIT(wait);
        __u16 lastCredits;
        int timeout = 1*HZ;
        int loop = 10;

        while (1) {
                /* Save Last credits */
                lastCredits = edge_port->txCredits;

                /* Did we get our Chase response */
                if (!edge_port->chaseResponsePending) {
                        dev_dbg(dev, "%s - Got Chase Response\n", __func__);

                        /* did we get all of our credit back? */
                        if (edge_port->txCredits == edge_port->maxTxCredits) {
                                dev_dbg(dev, "%s - Got all credits\n", __func__);
                                return;
                        }
                }

                /* Block the thread for a while */
                prepare_to_wait(&edge_port->wait_chase, &wait,
                                                TASK_UNINTERRUPTIBLE);
                schedule_timeout(timeout);
                finish_wait(&edge_port->wait_chase, &wait);

                if (lastCredits == edge_port->txCredits) {
                        /* No activity.. count down. */
                        loop--;
                        if (loop == 0) {
                                edge_port->chaseResponsePending = false;
                                dev_dbg(dev, "%s - Chase TIMEOUT\n", __func__);
                                return;
                        }
                } else {
                        /* Reset timeout value back to 10 seconds */
                        dev_dbg(dev, "%s - Last %d, Current %d\n", __func__,
                                        lastCredits, edge_port->txCredits);
                        loop = 10;
                }
        }
}


/************************************************************************
 *
 * block_until_tx_empty
 *
 *      This function will block the close until one of the following:
 *              1. TX count are 0
 *              2. The edgeport has stopped
 *              3. A timeout of 3 seconds without activity has expired
 *
 ************************************************************************/
static void block_until_tx_empty(struct edgeport_port *edge_port)
{
        struct device *dev = &edge_port->port->dev;
        DEFINE_WAIT(wait);
        struct TxFifo *fifo = &edge_port->txfifo;
        __u32 lastCount;
        int timeout = HZ/10;
        int loop = 30;

        while (1) {
                /* Save Last count */
                lastCount = fifo->count;

                /* Is the Edgeport Buffer empty? */

                if (lastCount == 0) {
                        dev_dbg(dev, "%s - TX Buffer Empty\n", __func__);
                        return;
                }

                /* Block the thread for a while */
                prepare_to_wait(&edge_port->wait_chase, &wait,
                                                TASK_UNINTERRUPTIBLE);
                schedule_timeout(timeout);
                finish_wait(&edge_port->wait_chase, &wait);

                dev_dbg(dev, "%s wait\n", __func__);

                if (lastCount == fifo->count) {
                        /* No activity.. count down. */
                        loop--;
                        if (loop == 0) {
                                dev_dbg(dev, "%s - TIMEOUT\n", __func__);
                                return;
                        }
                } else {
                        /* Reset timeout value back to seconds */
                        loop = 30;
                }
        }
}


/*****************************************************************************
 * edge_close
 *      this function is called by the tty driver when a port is closed
 *****************************************************************************/
static void edge_close(struct usb_serial_port *port)
{
        struct edgeport_serial *edge_serial;
        struct edgeport_port *edge_port;
        int status;

        edge_serial = usb_get_serial_data(port->serial);
        edge_port = usb_get_serial_port_data(port);
        if (edge_serial == NULL || edge_port == NULL)
                return;

        /* block until tx is empty */
        block_until_tx_empty(edge_port);

        edge_port->closePending = true;

        if (!edge_serial->is_epic ||
            edge_serial->epic_descriptor.Supports.IOSPChase) {
                /* flush and chase */
                edge_port->chaseResponsePending = true;

                dev_dbg(&port->dev, "%s - Sending IOSP_CMD_CHASE_PORT\n", __func__);
                status = send_iosp_ext_cmd(edge_port, IOSP_CMD_CHASE_PORT, 0);
                if (status == 0)
                        /* block until chase finished */
                        block_until_chase_response(edge_port);
                else
                        edge_port->chaseResponsePending = false;
        }

        if (!edge_serial->is_epic ||
            edge_serial->epic_descriptor.Supports.IOSPClose) {
               /* close the port */
                dev_dbg(&port->dev, "%s - Sending IOSP_CMD_CLOSE_PORT\n", __func__);
                send_iosp_ext_cmd(edge_port, IOSP_CMD_CLOSE_PORT, 0);
        }

        /* port->close = true; */
        edge_port->closePending = false;
        edge_port->open = false;
        edge_port->openPending = false;

        usb_kill_urb(edge_port->write_urb);

        if (edge_port->write_urb) {
                /* if this urb had a transfer buffer already
                                (old transfer) free it */
                kfree(edge_port->write_urb->transfer_buffer);
                usb_free_urb(edge_port->write_urb);
                edge_port->write_urb = NULL;
        }
        kfree(edge_port->txfifo.fifo);
        edge_port->txfifo.fifo = NULL;
}

/*****************************************************************************
 * SerialWrite
 *      this function is called by the tty driver when data should be written
 *      to the port.
 *      If successful, we return the number of bytes written, otherwise we
 *      return a negative error number.
 *****************************************************************************/
static int edge_write(struct tty_struct *tty, struct usb_serial_port *port,
                                        const unsigned char *data, int count)
{
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        struct TxFifo *fifo;
        int copySize;
        int bytesleft;
        int firsthalf;
        int secondhalf;
        unsigned long flags;

        if (edge_port == NULL)
                return -ENODEV;

        /* get a pointer to the Tx fifo */
        fifo = &edge_port->txfifo;

        spin_lock_irqsave(&edge_port->ep_lock, flags);

        /* calculate number of bytes to put in fifo */
        copySize = min((unsigned int)count,
                                (edge_port->txCredits - fifo->count));

        dev_dbg(&port->dev, "%s of %d byte(s) Fifo room  %d -- will copy %d bytes\n",
                __func__, count, edge_port->txCredits - fifo->count, copySize);

        /* catch writes of 0 bytes which the tty driver likes to give us,
           and when txCredits is empty */
        if (copySize == 0) {
                dev_dbg(&port->dev, "%s - copySize = Zero\n", __func__);
                goto finish_write;
        }

        /* queue the data
         * since we can never overflow the buffer we do not have to check for a
         * full condition
         *
         * the copy is done is two parts -- first fill to the end of the buffer
         * then copy the reset from the start of the buffer
         */
        bytesleft = fifo->size - fifo->head;
        firsthalf = min(bytesleft, copySize);
        dev_dbg(&port->dev, "%s - copy %d bytes of %d into fifo \n", __func__,
                firsthalf, bytesleft);

        /* now copy our data */
        memcpy(&fifo->fifo[fifo->head], data, firsthalf);
        usb_serial_debug_data(&port->dev, __func__, firsthalf, &fifo->fifo[fifo->head]);

        /* update the index and size */
        fifo->head  += firsthalf;
        fifo->count += firsthalf;

        /* wrap the index */
        if (fifo->head == fifo->size)
                fifo->head = 0;

        secondhalf = copySize-firsthalf;

        if (secondhalf) {
                dev_dbg(&port->dev, "%s - copy rest of data %d\n", __func__, secondhalf);
                memcpy(&fifo->fifo[fifo->head], &data[firsthalf], secondhalf);
                usb_serial_debug_data(&port->dev, __func__, secondhalf, &fifo->fifo[fifo->head]);
                /* update the index and size */
                fifo->count += secondhalf;
                fifo->head  += secondhalf;
                /* No need to check for wrap since we can not get to end of
                 * the fifo in this part
                 */
        }

finish_write:
        spin_unlock_irqrestore(&edge_port->ep_lock, flags);

        send_more_port_data((struct edgeport_serial *)
                        usb_get_serial_data(port->serial), edge_port);

        dev_dbg(&port->dev, "%s wrote %d byte(s) TxCredits %d, Fifo %d\n",
                __func__, copySize, edge_port->txCredits, fifo->count);

        return copySize;
}


/************************************************************************
 *
 * send_more_port_data()
 *
 *      This routine attempts to write additional UART transmit data
 *      to a port over the USB bulk pipe. It is called (1) when new
 *      data has been written to a port's TxBuffer from higher layers
 *      (2) when the peripheral sends us additional TxCredits indicating
 *      that it can accept more Tx data for a given port; and (3) when
 *      a bulk write completes successfully and we want to see if we
 *      can transmit more.
 *
 ************************************************************************/
static void send_more_port_data(struct edgeport_serial *edge_serial,
                                        struct edgeport_port *edge_port)
{
        struct TxFifo   *fifo = &edge_port->txfifo;
        struct device   *dev = &edge_port->port->dev;
        struct urb      *urb;
        unsigned char   *buffer;
        int             status;
        int             count;
        int             bytesleft;
        int             firsthalf;
        int             secondhalf;
        unsigned long   flags;

        spin_lock_irqsave(&edge_port->ep_lock, flags);

        if (edge_port->write_in_progress ||
            !edge_port->open             ||
            (fifo->count == 0)) {
                dev_dbg(dev, "%s EXIT - fifo %d, PendingWrite = %d\n",
                        __func__, fifo->count, edge_port->write_in_progress);
                goto exit_send;
        }

        /* since the amount of data in the fifo will always fit into the
         * edgeport buffer we do not need to check the write length
         *
         * Do we have enough credits for this port to make it worthwhile
         * to bother queueing a write. If it's too small, say a few bytes,
         * it's better to wait for more credits so we can do a larger write.
         */
        if (edge_port->txCredits < EDGE_FW_GET_TX_CREDITS_SEND_THRESHOLD(edge_port->maxTxCredits, EDGE_FW_BULK_MAX_PACKET_SIZE)) {
                dev_dbg(dev, "%s Not enough credit - fifo %d TxCredit %d\n",
                        __func__, fifo->count, edge_port->txCredits);
                goto exit_send;
        }

        /* lock this write */
        edge_port->write_in_progress = true;

        /* get a pointer to the write_urb */
        urb = edge_port->write_urb;

        /* make sure transfer buffer is freed */
        kfree(urb->transfer_buffer);
        urb->transfer_buffer = NULL;

        /* build the data header for the buffer and port that we are about
           to send out */
        count = fifo->count;
        buffer = kmalloc(count+2, GFP_ATOMIC);
        if (!buffer) {
                edge_port->write_in_progress = false;
                goto exit_send;
        }
        buffer[0] = IOSP_BUILD_DATA_HDR1(edge_port->port->port_number, count);
        buffer[1] = IOSP_BUILD_DATA_HDR2(edge_port->port->port_number, count);

        /* now copy our data */
        bytesleft =  fifo->size - fifo->tail;
        firsthalf = min(bytesleft, count);
        memcpy(&buffer[2], &fifo->fifo[fifo->tail], firsthalf);
        fifo->tail  += firsthalf;
        fifo->count -= firsthalf;
        if (fifo->tail == fifo->size)
                fifo->tail = 0;

        secondhalf = count-firsthalf;
        if (secondhalf) {
                memcpy(&buffer[2+firsthalf], &fifo->fifo[fifo->tail],
                                                                secondhalf);
                fifo->tail  += secondhalf;
                fifo->count -= secondhalf;
        }

        if (count)
                usb_serial_debug_data(&edge_port->port->dev, __func__, count, &buffer[2]);

        /* fill up the urb with all of our data and submit it */
        usb_fill_bulk_urb(urb, edge_serial->serial->dev,
                        usb_sndbulkpipe(edge_serial->serial->dev,
                                        edge_serial->bulk_out_endpoint),
                        buffer, count+2,
                        edge_bulk_out_data_callback, edge_port);

        /* decrement the number of credits we have by the number we just sent */
        edge_port->txCredits -= count;
        edge_port->port->icount.tx += count;

        status = usb_submit_urb(urb, GFP_ATOMIC);
        if (status) {
                /* something went wrong */
                dev_err_console(edge_port->port,
                        "%s - usb_submit_urb(write bulk) failed, status = %d, data lost\n",
                                __func__, status);
                edge_port->write_in_progress = false;

                /* revert the credits as something bad happened. */
                edge_port->txCredits += count;
                edge_port->port->icount.tx -= count;
        }
        dev_dbg(dev, "%s wrote %d byte(s) TxCredit %d, Fifo %d\n",
                __func__, count, edge_port->txCredits, fifo->count);

exit_send:
        spin_unlock_irqrestore(&edge_port->ep_lock, flags);
}


/*****************************************************************************
 * edge_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 (the txCredits)
 *      otherwise we return a negative error number.
 *****************************************************************************/
static int edge_write_room(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        int room;
        unsigned long flags;

        if (edge_port == NULL)
                return 0;
        if (edge_port->closePending)
                return 0;

        if (!edge_port->open) {
                dev_dbg(&port->dev, "%s - port not opened\n", __func__);
                return 0;
        }

        /* total of both buffers is still txCredit */
        spin_lock_irqsave(&edge_port->ep_lock, flags);
        room = edge_port->txCredits - edge_port->txfifo.count;
        spin_unlock_irqrestore(&edge_port->ep_lock, flags);

        dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
        return room;
}


/*****************************************************************************
 * edge_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 edge_chars_in_buffer(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        int num_chars;
        unsigned long flags;

        if (edge_port == NULL)
                return 0;
        if (edge_port->closePending)
                return 0;

        if (!edge_port->open) {
                dev_dbg(&port->dev, "%s - port not opened\n", __func__);
                return 0;
        }

        spin_lock_irqsave(&edge_port->ep_lock, flags);
        num_chars = edge_port->maxTxCredits - edge_port->txCredits +
                                                edge_port->txfifo.count;
        spin_unlock_irqrestore(&edge_port->ep_lock, flags);
        if (num_chars) {
                dev_dbg(&port->dev, "%s - returns %d\n", __func__, num_chars);
        }

        return num_chars;
}


/*****************************************************************************
 * SerialThrottle
 *      this function is called by the tty driver when it wants to stop the data
 *      being read from the port.
 *****************************************************************************/
static void edge_throttle(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        int status;

        if (edge_port == NULL)
                return;

        if (!edge_port->open) {
                dev_dbg(&port->dev, "%s - port not opened\n", __func__);
                return;
        }

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

        /* if we are implementing RTS/CTS, toggle that line */
        if (C_CRTSCTS(tty)) {
                edge_port->shadowMCR &= ~MCR_RTS;
                status = send_cmd_write_uart_register(edge_port, MCR,
                                                        edge_port->shadowMCR);
                if (status != 0)
                        return;
        }
}


/*****************************************************************************
 * edge_unthrottle
 *      this function is called by the tty driver when it wants to resume the
 *      data being read from the port (called after SerialThrottle is called)
 *****************************************************************************/
static void edge_unthrottle(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        int status;

        if (edge_port == NULL)
                return;

        if (!edge_port->open) {
                dev_dbg(&port->dev, "%s - port not opened\n", __func__);
                return;
        }

        /* if we are implementing XON/XOFF, send the start character */
        if (I_IXOFF(tty)) {
                unsigned char start_char = START_CHAR(tty);
                status = edge_write(tty, port, &start_char, 1);
                if (status <= 0)
                        return;
        }
        /* if we are implementing RTS/CTS, toggle that line */
        if (C_CRTSCTS(tty)) {
                edge_port->shadowMCR |= MCR_RTS;
                send_cmd_write_uart_register(edge_port, MCR,
                                                edge_port->shadowMCR);
        }
}


/*****************************************************************************
 * SerialSetTermios
 *      this function is called by the tty driver when it wants to change
 * the termios structure
 *****************************************************************************/
static void edge_set_termios(struct tty_struct *tty,
        struct usb_serial_port *port, struct ktermios *old_termios)
{
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        unsigned int cflag;

        cflag = tty->termios.c_cflag;
        dev_dbg(&port->dev, "%s - clfag %08x iflag %08x\n", __func__, tty->termios.c_cflag, tty->termios.c_iflag);
        dev_dbg(&port->dev, "%s - old clfag %08x old iflag %08x\n", __func__, old_termios->c_cflag, old_termios->c_iflag);

        if (edge_port == NULL)
                return;

        if (!edge_port->open) {
                dev_dbg(&port->dev, "%s - port not opened\n", __func__);
                return;
        }

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


/*****************************************************************************
 * 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 edgeport_port *edge_port,
                                                unsigned int __user *value)
{
        unsigned int result = 0;
        unsigned long flags;

        spin_lock_irqsave(&edge_port->ep_lock, flags);
        if (edge_port->maxTxCredits == edge_port->txCredits &&
            edge_port->txfifo.count == 0) {
                dev_dbg(&edge_port->port->dev, "%s -- Empty\n", __func__);
                result = TIOCSER_TEMT;
        }
        spin_unlock_irqrestore(&edge_port->ep_lock, flags);

        if (copy_to_user(value, &result, sizeof(int)))
                return -EFAULT;
        return 0;
}

static int edge_tiocmset(struct tty_struct *tty,
                                        unsigned int set, unsigned int clear)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        unsigned int mcr;

        mcr = edge_port->shadowMCR;
        if (set & TIOCM_RTS)
                mcr |= MCR_RTS;
        if (set & TIOCM_DTR)
                mcr |= MCR_DTR;
        if (set & TIOCM_LOOP)
                mcr |= MCR_LOOPBACK;

        if (clear & TIOCM_RTS)
                mcr &= ~MCR_RTS;
        if (clear & TIOCM_DTR)
                mcr &= ~MCR_DTR;
        if (clear & TIOCM_LOOP)
                mcr &= ~MCR_LOOPBACK;

        edge_port->shadowMCR = mcr;

        send_cmd_write_uart_register(edge_port, MCR, edge_port->shadowMCR);

        return 0;
}

static int edge_tiocmget(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        unsigned int result = 0;
        unsigned int msr;
        unsigned int mcr;

        msr = edge_port->shadowMSR;
        mcr = edge_port->shadowMCR;
        result = ((mcr & MCR_DTR)       ? TIOCM_DTR: 0)   /* 0x002 */
                  | ((mcr & MCR_RTS)    ? TIOCM_RTS: 0)   /* 0x004 */
                  | ((msr & EDGEPORT_MSR_CTS)   ? TIOCM_CTS: 0)   /* 0x020 */
                  | ((msr & EDGEPORT_MSR_CD)    ? TIOCM_CAR: 0)   /* 0x040 */
                  | ((msr & EDGEPORT_MSR_RI)    ? TIOCM_RI:  0)   /* 0x080 */
                  | ((msr & EDGEPORT_MSR_DSR)   ? TIOCM_DSR: 0);  /* 0x100 */

        return result;
}

static int get_serial_info(struct edgeport_port *edge_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                = edge_port->port->minor;
        tmp.port                = edge_port->port->port_number;
        tmp.irq                 = 0;
        tmp.flags               = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
        tmp.xmit_fifo_size      = edge_port->maxTxCredits;
        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;
}


/*****************************************************************************
 * SerialIoctl
 *      this function handles any ioctl calls to the driver
 *****************************************************************************/
static int edge_ioctl(struct tty_struct *tty,
                                        unsigned int cmd, unsigned long arg)
{
        struct usb_serial_port *port = tty->driver_data;
        DEFINE_WAIT(wait);
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);

        switch (cmd) {
        case TIOCSERGETLSR:
                dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
                return get_lsr_info(edge_port, (unsigned int __user *) arg);

        case TIOCGSERIAL:
                dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
                return get_serial_info(edge_port, (struct serial_struct __user *) arg);
        }
        return -ENOIOCTLCMD;
}


/*****************************************************************************
 * SerialBreak
 *      this function sends a break to the port
 *****************************************************************************/
static void edge_break(struct tty_struct *tty, int break_state)
{
        struct usb_serial_port *port = tty->driver_data;
        struct edgeport_port *edge_port = usb_get_serial_port_data(port);
        struct edgeport_serial *edge_serial = usb_get_serial_data(port->serial);
        int status;

        if (!edge_serial->is_epic ||
            edge_serial->epic_descriptor.Supports.IOSPChase) {
                /* flush and chase */
                edge_port->chaseResponsePending = true;

                dev_dbg(&port->dev, "%s - Sending IOSP_CMD_CHASE_PORT\n", __func__);
                status = send_iosp_ext_cmd(edge_port, IOSP_CMD_CHASE_PORT, 0);
                if (status == 0) {
                        /* block until chase finished */
                        block_until_chase_response(edge_port);
                } else {
                        edge_port->chaseResponsePending = false;
                }
        }

        if (!edge_serial->is_epic ||
            edge_serial->epic_descriptor.Supports.IOSPSetClrBreak) {
                if (break_state == -1) {
                        dev_dbg(&port->dev, "%s - Sending IOSP_CMD_SET_BREAK\n", __func__);
                        status = send_iosp_ext_cmd(edge_port,
                                                IOSP_CMD_SET_BREAK, 0);
                } else {
                        dev_dbg(&port->dev, "%s - Sending IOSP_CMD_CLEAR_BREAK\n", __func__);
                        status = send_iosp_ext_cmd(edge_port,
                                                IOSP_CMD_CLEAR_BREAK, 0);
                }
                if (status)
                        dev_dbg(&port->dev, "%s - error sending break set/clear command.\n",
                                __func__);
        }
}


/*****************************************************************************
 * process_rcvd_data
 *      this function handles the data received on the bulk in pipe.
 *****************************************************************************/
static void process_rcvd_data(struct edgeport_serial *edge_serial,
                                unsigned char *buffer, __u16 bufferLength)
{
        struct device *dev = &edge_serial->serial->dev->dev;
        struct usb_serial_port *port;
        struct edgeport_port *edge_port;
        __u16 lastBufferLength;
        __u16 rxLen;

        lastBufferLength = bufferLength + 1;

        while (bufferLength > 0) {
                /* failsafe incase we get a message that we don't understand */
                if (lastBufferLength == bufferLength) {
                        dev_dbg(dev, "%s - stuck in loop, exiting it.\n", __func__);
                        break;
                }
                lastBufferLength = bufferLength;

                switch (edge_serial->rxState) {
                case EXPECT_HDR1:
                        edge_serial->rxHeader1 = *buffer;
                        ++buffer;
                        --bufferLength;

                        if (bufferLength == 0) {
                                edge_serial->rxState = EXPECT_HDR2;
                                break;
                        }
                        /* otherwise, drop on through */
                case EXPECT_HDR2:
                        edge_serial->rxHeader2 = *buffer;
                        ++buffer;
                        --bufferLength;

                        dev_dbg(dev, "%s - Hdr1=%02X Hdr2=%02X\n", __func__,
                                edge_serial->rxHeader1, edge_serial->rxHeader2);
                        /* Process depending on whether this header is
                         * data or status */

                        if (IS_CMD_STAT_HDR(edge_serial->rxHeader1)) {
                                /* Decode this status header and go to
                                 * EXPECT_HDR1 (if we can process the status
                                 * with only 2 bytes), or go to EXPECT_HDR3 to
                                 * get the third byte. */
                                edge_serial->rxPort =
                                    IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
                                edge_serial->rxStatusCode =
                                    IOSP_GET_STATUS_CODE(
                                                edge_serial->rxHeader1);

                                if (!IOSP_STATUS_IS_2BYTE(
                                                edge_serial->rxStatusCode)) {
                                        /* This status needs additional bytes.
                                         * Save what we have and then wait for
                                         * more data.
                                         */
                                        edge_serial->rxStatusParam
                                                = edge_serial->rxHeader2;
                                        edge_serial->rxState = EXPECT_HDR3;
                                        break;
                                }
                                /* We have all the header bytes, process the
                                   status now */
                                process_rcvd_status(edge_serial,
                                                edge_serial->rxHeader2, 0);
                                edge_serial->rxState = EXPECT_HDR1;
                                break;
                        } else {
                                edge_serial->rxPort =
                                    IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
                                edge_serial->rxBytesRemaining =
                                    IOSP_GET_HDR_DATA_LEN(
                                                edge_serial->rxHeader1,
                                                edge_serial->rxHeader2);
                                dev_dbg(dev, "%s - Data for Port %u Len %u\n",
                                        __func__,
                                        edge_serial->rxPort,
                                        edge_serial->rxBytesRemaining);

                                /* ASSERT(DevExt->RxPort < DevExt->NumPorts);
                                 * ASSERT(DevExt->RxBytesRemaining <
                                 *              IOSP_MAX_DATA_LENGTH);
                                 */

                                if (bufferLength == 0) {
                                        edge_serial->rxState = EXPECT_DATA;
                                        break;
                                }
                                /* Else, drop through */
                        }
                case EXPECT_DATA: /* Expect data */
                        if (bufferLength < edge_serial->rxBytesRemaining) {
                                rxLen = bufferLength;
                                /* Expect data to start next buffer */
                                edge_serial->rxState = EXPECT_DATA;
                        } else {
                                /* BufLen >= RxBytesRemaining */
                                rxLen = edge_serial->rxBytesRemaining;
                                /* Start another header next time */
                                edge_serial->rxState = EXPECT_HDR1;
                        }

                        bufferLength -= rxLen;
                        edge_serial->rxBytesRemaining -= rxLen;

                        /* spit this data back into the tty driver if this
                           port is open */
                        if (rxLen) {
                                port = edge_serial->serial->port[
                                                        edge_serial->rxPort];
                                edge_port = usb_get_serial_port_data(port);
                                if (edge_port->open) {
                                        dev_dbg(dev, "%s - Sending %d bytes to TTY for port %d\n",
                                                __func__, rxLen,
                                                edge_serial->rxPort);
                                        edge_tty_recv(edge_port->port, buffer,
                                                        rxLen);
                                        edge_port->port->icount.rx += rxLen;
                                }
                                buffer += rxLen;
                        }
                        break;

                case EXPECT_HDR3:       /* Expect 3rd byte of status header */
                        edge_serial->rxHeader3 = *buffer;
                        ++buffer;
                        --bufferLength;

                        /* We have all the header bytes, process the
                           status now */
                        process_rcvd_status(edge_serial,
                                edge_serial->rxStatusParam,
                                edge_serial->rxHeader3);
                        edge_serial->rxState = EXPECT_HDR1;
                        break;
                }
        }
}


/*****************************************************************************
 * process_rcvd_status
 *      this function handles the any status messages received on the
 *      bulk in pipe.
 *****************************************************************************/
static void process_rcvd_status(struct edgeport_serial *edge_serial,
                                                __u8 byte2, __u8 byte3)
{
        struct usb_serial_port *port;
        struct edgeport_port *edge_port;
        struct tty_struct *tty;
        struct device *dev;
        __u8 code = edge_serial->rxStatusCode;

        /* switch the port pointer to the one being currently talked about */
        port = edge_serial->serial->port[edge_serial->rxPort];
        edge_port = usb_get_serial_port_data(port);
        if (edge_port == NULL) {
                dev_err(&edge_serial->serial->dev->dev,
                        "%s - edge_port == NULL for port %d\n",
                                        __func__, edge_serial->rxPort);
                return;
        }
        dev = &port->dev;

        if (code == IOSP_EXT_STATUS) {
                switch (byte2) {
                case IOSP_EXT_STATUS_CHASE_RSP:
                        /* we want to do EXT status regardless of port
                         * open/closed */
                        dev_dbg(dev, "%s - Port %u EXT CHASE_RSP Data = %02x\n",
                                __func__, edge_serial->rxPort, byte3);
                        /* Currently, the only EXT_STATUS is Chase, so process
                         * here instead of one more call to one more subroutine
                         * If/when more EXT_STATUS, there'll be more work to do
                         * Also, we currently clear flag and close the port
                         * regardless of content of above's Byte3.
                         * We could choose to do something else when Byte3 says
                         * Timeout on Chase from Edgeport, like wait longer in
                         * block_until_chase_response, but for now we don't.
                         */
                        edge_port->chaseResponsePending = false;
                        wake_up(&edge_port->wait_chase);
                        return;

                case IOSP_EXT_STATUS_RX_CHECK_RSP:
                        dev_dbg(dev, "%s ========== Port %u CHECK_RSP Sequence = %02x =============\n",
                                __func__, edge_serial->rxPort, byte3);
                        /* Port->RxCheckRsp = true; */
                        return;
                }
        }

        if (code == IOSP_STATUS_OPEN_RSP) {
                edge_port->txCredits = GET_TX_BUFFER_SIZE(byte3);
                edge_port->maxTxCredits = edge_port->txCredits;
                dev_dbg(dev, "%s - Port %u Open Response Initial MSR = %02x TxBufferSize = %d\n",
                        __func__, edge_serial->rxPort, byte2, edge_port->txCredits);
                handle_new_msr(edge_port, byte2);

                /* send the current line settings to the port so we are
                   in sync with any further termios calls */
                tty = tty_port_tty_get(&edge_port->port->port);
                if (tty) {
                        change_port_settings(tty,
                                edge_port, &tty->termios);
                        tty_kref_put(tty);
                }

                /* we have completed the open */
                edge_port->openPending = false;
                edge_port->open = true;
                wake_up(&edge_port->wait_open);
                return;
        }

        /* If port is closed, silently discard all rcvd status. We can
         * have cases where buffered status is received AFTER the close
         * port command is sent to the Edgeport.
         */
        if (!edge_port->open || edge_port->closePending)
                return;

        switch (code) {
        /* Not currently sent by Edgeport */
        case IOSP_STATUS_LSR:
                dev_dbg(dev, "%s - Port %u LSR Status = %02x\n",
                        __func__, edge_serial->rxPort, byte2);
                handle_new_lsr(edge_port, false, byte2, 0);
                break;

        case IOSP_STATUS_LSR_DATA:
                dev_dbg(dev, "%s - Port %u LSR Status = %02x, Data = %02x\n",
                        __func__, edge_serial->rxPort, byte2, byte3);
                /* byte2 is LSR Register */
                /* byte3 is broken data byte */
                handle_new_lsr(edge_port, true, byte2, byte3);
                break;
        /*
         *      case IOSP_EXT_4_STATUS:
         *              dev_dbg(dev, "%s - Port %u LSR Status = %02x Data = %02x\n",
         *                      __func__, edge_serial->rxPort, byte2, byte3);
         *              break;
         */
        case IOSP_STATUS_MSR:
                dev_dbg(dev, "%s - Port %u MSR Status = %02x\n",
                        __func__, edge_serial->rxPort, byte2);
                /*
                 * Process this new modem status and generate appropriate
                 * events, etc, based on the new status. This routine
                 * also saves the MSR in Port->ShadowMsr.
                 */
                handle_new_msr(edge_port, byte2);
                break;

        default:
                dev_dbg(dev, "%s - Unrecognized IOSP status code %u\n", __func__, code);
                break;
        }
}


/*****************************************************************************
 * edge_tty_recv
 *      this function passes data on to the tty flip buffer
 *****************************************************************************/
static void edge_tty_recv(struct usb_serial_port *port, unsigned char *data,
                int length)
{
        int cnt;

        cnt = tty_insert_flip_string(&port->port, data, length);
        if (cnt < length) {
                dev_err(&port->dev, "%s - dropping data, %d bytes lost\n",
                                __func__, length - cnt);
        }
        data += cnt;
        length -= cnt;

        tty_flip_buffer_push(&port->port);
}


/*****************************************************************************
 * handle_new_msr
 *      this function handles any change to the msr register for a port.
 *****************************************************************************/
static void handle_new_msr(struct edgeport_port *edge_port, __u8 newMsr)
{
        struct  async_icount *icount;

        if (newMsr & (EDGEPORT_MSR_DELTA_CTS | EDGEPORT_MSR_DELTA_DSR |
                        EDGEPORT_MSR_DELTA_RI | EDGEPORT_MSR_DELTA_CD)) {
                icount = &edge_port->port->icount;

                /* update input line counters */
                if (newMsr & EDGEPORT_MSR_DELTA_CTS)
                        icount->cts++;
                if (newMsr & EDGEPORT_MSR_DELTA_DSR)
                        icount->dsr++;
                if (newMsr & EDGEPORT_MSR_DELTA_CD)
                        icount->dcd++;
                if (newMsr & EDGEPORT_MSR_DELTA_RI)
                        icount->rng++;
                wake_up_interruptible(&edge_port->port->port.delta_msr_wait);
        }

        /* Save the new modem status */
        edge_port->shadowMSR = newMsr & 0xf0;
}


/*****************************************************************************
 * handle_new_lsr
 *      this function handles any change to the lsr register for a port.
 *****************************************************************************/
static void handle_new_lsr(struct edgeport_port *edge_port, __u8 lsrData,
                                                        __u8 lsr, __u8 data)
{
        __u8 newLsr = (__u8) (lsr & (__u8)
                (LSR_OVER_ERR | LSR_PAR_ERR | LSR_FRM_ERR | LSR_BREAK));
        struct async_icount *icount;

        edge_port->shadowLSR = lsr;

        if (newLsr & LSR_BREAK) {
                /*
                 * Parity and Framing errors only count if they
                 * occur exclusive of a break being
                 * received.
                 */
                newLsr &= (__u8)(LSR_OVER_ERR | LSR_BREAK);
        }

        /* Place LSR data byte into Rx buffer */
        if (lsrData)
                edge_tty_recv(edge_port->port, &data, 1);

        /* update input line counters */
        icount = &edge_port->port->icount;
        if (newLsr & LSR_BREAK)
                icount->brk++;
        if (newLsr & LSR_OVER_ERR)
                icount->overrun++;
        if (newLsr & LSR_PAR_ERR)
                icount->parity++;
        if (newLsr & LSR_FRM_ERR)
                icount->frame++;
}

/****************************************************************************
 * sram_write
 *      writes a number of bytes to the Edgeport device's sram starting at the
 *      given address.
 *      If successful returns the number of bytes written, otherwise it returns
 *      a negative error number of the problem.
 ****************************************************************************/
static int sram_write(struct usb_serial *serial, __u16 extAddr, __u16 addr,
                                        __u16 length, const __u8 *data)
{
        int result;
        __u16 current_length;
        unsigned char *transfer_buffer;

        dev_dbg(&serial->dev->dev, "%s - %x, %x, %d\n", __func__, extAddr, addr, length);

        transfer_buffer =  kmalloc(64, GFP_KERNEL);
        if (!transfer_buffer)
                return -ENOMEM;

        /* need to split these writes up into 64 byte chunks */
        result = 0;
        while (length > 0) {
                if (length > 64)
                        current_length = 64;
                else
                        current_length = length;

/*              dev_dbg(&serial->dev->dev, "%s - writing %x, %x, %d\n", __func__, extAddr, addr, current_length); */
                memcpy(transfer_buffer, data, current_length);
                result = usb_control_msg(serial->dev,
                                        usb_sndctrlpipe(serial->dev, 0),
                                        USB_REQUEST_ION_WRITE_RAM,
                                        0x40, addr, extAddr, transfer_buffer,
                                        current_length, 300);
                if (result < 0)
                        break;
                length -= current_length;
                addr += current_length;
                data += current_length;
        }

        kfree(transfer_buffer);
        return result;
}


/****************************************************************************
 * rom_write
 *      writes a number of bytes to the Edgeport device's ROM starting at the
 *      given address.
 *      If successful returns the number of bytes written, otherwise it returns
 *      a negative error number of the problem.
 ****************************************************************************/
static int rom_write(struct usb_serial *serial, __u16 extAddr, __u16 addr,
                                        __u16 length, const __u8 *data)
{
        int result;
        __u16 current_length;
        unsigned char *transfer_buffer;

        transfer_buffer =  kmalloc(64, GFP_KERNEL);
        if (!transfer_buffer)
                return -ENOMEM;

        /* need to split these writes up into 64 byte chunks */
        result = 0;
        while (length > 0) {
                if (length > 64)
                        current_length = 64;
                else
                        current_length = length;
                memcpy(transfer_buffer, data, current_length);
                result = usb_control_msg(serial->dev,
                                        usb_sndctrlpipe(serial->dev, 0),
                                        USB_REQUEST_ION_WRITE_ROM, 0x40,
                                        addr, extAddr,
                                        transfer_buffer, current_length, 300);
                if (result < 0)
                        break;
                length -= current_length;
                addr += current_length;
                data += current_length;
        }

        kfree(transfer_buffer);
        return result;
}


/****************************************************************************
 * rom_read
 *      reads a number of bytes from the Edgeport device starting at the given
 *      address.
 *      If successful returns the number of bytes read, otherwise it returns
 *      a negative error number of the problem.
 ****************************************************************************/
static int rom_read(struct usb_serial *serial, __u16 extAddr,
                                        __u16 addr, __u16 length, __u8 *data)
{
        int result;
        __u16 current_length;
        unsigned char *transfer_buffer;

        transfer_buffer =  kmalloc(64, GFP_KERNEL);
        if (!transfer_buffer)
                return -ENOMEM;

        /* need to split these reads up into 64 byte chunks */
        result = 0;
        while (length > 0) {
                if (length > 64)
                        current_length = 64;
                else
                        current_length = length;
                result = usb_control_msg(serial->dev,
                                        usb_rcvctrlpipe(serial->dev, 0),
                                        USB_REQUEST_ION_READ_ROM,
                                        0xC0, addr, extAddr, transfer_buffer,
                                        current_length, 300);
                if (result < 0)
                        break;
                memcpy(data, transfer_buffer, current_length);
                length -= current_length;
                addr += current_length;
                data += current_length;
        }

        kfree(transfer_buffer);
        return result;
}


/****************************************************************************
 * send_iosp_ext_cmd
 *      Is used to send a IOSP message to the Edgeport device
 ****************************************************************************/
static int send_iosp_ext_cmd(struct edgeport_port *edge_port,
                                                __u8 command, __u8 param)
{
        unsigned char   *buffer;
        unsigned char   *currentCommand;
        int             length = 0;
        int             status = 0;

        buffer = kmalloc(10, GFP_ATOMIC);
        if (!buffer)
                return -ENOMEM;

        currentCommand = buffer;

        MAKE_CMD_EXT_CMD(&currentCommand, &length, edge_port->port->port_number,
                         command, param);

        status = write_cmd_usb(edge_port, buffer, length);
        if (status) {
                /* something bad happened, let's free up the memory */
                kfree(buffer);
        }

        return status;
}


/*****************************************************************************
 * write_cmd_usb
 *      this function writes the given buffer out to the bulk write endpoint.
 *****************************************************************************/
static int write_cmd_usb(struct edgeport_port *edge_port,
                                        unsigned char *buffer, int length)
{
        struct edgeport_serial *edge_serial =
                                usb_get_serial_data(edge_port->port->serial);
        struct device *dev = &edge_port->port->dev;
        int status = 0;
        struct urb *urb;

        usb_serial_debug_data(dev, __func__, length, buffer);

        /* Allocate our next urb */
        urb = usb_alloc_urb(0, GFP_ATOMIC);
        if (!urb)
                return -ENOMEM;

        atomic_inc(&CmdUrbs);
        dev_dbg(dev, "%s - ALLOCATE URB %p (outstanding %d)\n",
                __func__, urb, atomic_read(&CmdUrbs));

        usb_fill_bulk_urb(urb, edge_serial->serial->dev,
                        usb_sndbulkpipe(edge_serial->serial->dev,
                                        edge_serial->bulk_out_endpoint),
                        buffer, length, edge_bulk_out_cmd_callback, edge_port);

        edge_port->commandPending = true;
        status = usb_submit_urb(urb, GFP_ATOMIC);

        if (status) {
                /* something went wrong */
                dev_err(dev, "%s - usb_submit_urb(write command) failed, status = %d\n",
                        __func__, status);
                usb_kill_urb(urb);
                usb_free_urb(urb);
                atomic_dec(&CmdUrbs);
                return status;
        }

#if 0
        wait_event(&edge_port->wait_command, !edge_port->commandPending);

        if (edge_port->commandPending) {
                /* command timed out */
                dev_dbg(dev, "%s - command timed out\n", __func__);
                status = -EINVAL;
        }
#endif
        return status;
}


/*****************************************************************************
 * 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 edgeport_port *edge_port,
                                                                int baudRate)
{
        struct edgeport_serial *edge_serial =
                                usb_get_serial_data(edge_port->port->serial);
        struct device *dev = &edge_port->port->dev;
        unsigned char *cmdBuffer;
        unsigned char *currCmd;
        int cmdLen = 0;
        int divisor;
        int status;
        u32 number = edge_port->port->port_number;

        if (edge_serial->is_epic &&
            !edge_serial->epic_descriptor.Supports.IOSPSetBaudRate) {
                dev_dbg(dev, "SendCmdWriteBaudRate - NOT Setting baud rate for port, baud = %d\n",
                        baudRate);
                return 0;
        }

        dev_dbg(dev, "%s - baud = %d\n", __func__, baudRate);

        status = calc_baud_rate_divisor(dev, baudRate, &divisor);
        if (status) {
                dev_err(dev, "%s - bad baud rate\n", __func__);
                return status;
        }

        /* Alloc memory for the string of commands. */
        cmdBuffer =  kmalloc(0x100, GFP_ATOMIC);
        if (!cmdBuffer)
                return -ENOMEM;

        currCmd = cmdBuffer;

        /* Enable access to divisor latch */
        MAKE_CMD_WRITE_REG(&currCmd, &cmdLen, number, LCR, LCR_DL_ENABLE);

        /* Write the divisor itself */
        MAKE_CMD_WRITE_REG(&currCmd, &cmdLen, number, DLL, LOW8(divisor));
        MAKE_CMD_WRITE_REG(&currCmd, &cmdLen, number, DLM, HIGH8(divisor));

        /* Restore original value to disable access to divisor latch */
        MAKE_CMD_WRITE_REG(&currCmd, &cmdLen, number, LCR,
                                                edge_port->shadowLCR);

        status = write_cmd_usb(edge_port, cmdBuffer, cmdLen);
        if (status) {
                /* something bad happened, let's free up the memory */
                kfree(cmdBuffer);
        }

        return status;
}


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

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

        /* We have tried all of the standard baud rates
         * lets try to calculate the divisor for this baud rate
         * Make sure the baud rate is reasonable */
        if (baudrate > 50 && baudrate < 230400) {
                /* get divisor */
                custom = (__u16)((230400L + baudrate/2) / baudrate);

                *divisor = custom;

                dev_dbg(dev, "%s - Baud %d = %d\n", __func__, baudrate, custom);
                return 0;
        }

        return -1;
}


/*****************************************************************************
 * send_cmd_write_uart_register
 *  this function builds up a uart register message and sends to the device.
 *****************************************************************************/
static int send_cmd_write_uart_register(struct edgeport_port *edge_port,
                                                __u8 regNum, __u8 regValue)
{
        struct edgeport_serial *edge_serial =
                                usb_get_serial_data(edge_port->port->serial);
        struct device *dev = &edge_port->port->dev;
        unsigned char *cmdBuffer;
        unsigned char *currCmd;
        unsigned long cmdLen = 0;
        int status;

        dev_dbg(dev, "%s - write to %s register 0x%02x\n",
                (regNum == MCR) ? "MCR" : "LCR", __func__, regValue);

        if (edge_serial->is_epic &&
            !edge_serial->epic_descriptor.Supports.IOSPWriteMCR &&
            regNum == MCR) {
                dev_dbg(dev, "SendCmdWriteUartReg - Not writing to MCR Register\n");
                return 0;
        }

        if (edge_serial->is_epic &&
            !edge_serial->epic_descriptor.Supports.IOSPWriteLCR &&
            regNum == LCR) {
                dev_dbg(dev, "SendCmdWriteUartReg - Not writing to LCR Register\n");
                return 0;
        }

        /* Alloc memory for the string of commands. */
        cmdBuffer = kmalloc(0x10, GFP_ATOMIC);
        if (cmdBuffer == NULL)
                return -ENOMEM;

        currCmd = cmdBuffer;

        /* Build a cmd in the buffer to write the given register */
        MAKE_CMD_WRITE_REG(&currCmd, &cmdLen, edge_port->port->port_number,
                           regNum, regValue);

        status = write_cmd_usb(edge_port, cmdBuffer, cmdLen);
        if (status) {
                /* something bad happened, let's free up the memory */
                kfree(cmdBuffer);
        }

        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 edgeport_port *edge_port, struct ktermios *old_termios)
{
        struct device *dev = &edge_port->port->dev;
        struct edgeport_serial *edge_serial =
                        usb_get_serial_data(edge_port->port->serial);
        int baud;
        unsigned cflag;
        __u8 mask = 0xff;
        __u8 lData;
        __u8 lParity;
        __u8 lStop;
        __u8 rxFlow;
        __u8 txFlow;
        int status;

        if (!edge_port->open &&
            !edge_port->openPending) {
                dev_dbg(dev, "%s - port not opened\n", __func__);
                return;
        }

        cflag = tty->termios.c_cflag;

        switch (cflag & CSIZE) {
        case CS5:
                lData = LCR_BITS_5; mask = 0x1f;
                dev_dbg(dev, "%s - data bits = 5\n", __func__);
                break;
        case CS6:
                lData = LCR_BITS_6; mask = 0x3f;
                dev_dbg(dev, "%s - data bits = 6\n", __func__);
                break;
        case CS7:
                lData = LCR_BITS_7; mask = 0x7f;
                dev_dbg(dev, "%s - data bits = 7\n", __func__);
                break;
        default:
        case CS8:
                lData = LCR_BITS_8;
                dev_dbg(dev, "%s - data bits = 8\n", __func__);
                break;
        }

        lParity = LCR_PAR_NONE;
        if (cflag & PARENB) {
                if (cflag & CMSPAR) {
                        if (cflag & PARODD) {
                                lParity = LCR_PAR_MARK;
                                dev_dbg(dev, "%s - parity = mark\n", __func__);
                        } else {
                                lParity = LCR_PAR_SPACE;
                                dev_dbg(dev, "%s - parity = space\n", __func__);
                        }
                } else if (cflag & PARODD) {
                        lParity = LCR_PAR_ODD;
                        dev_dbg(dev, "%s - parity = odd\n", __func__);
                } else {
                        lParity = LCR_PAR_EVEN;
                        dev_dbg(dev, "%s - parity = even\n", __func__);
                }
        } else {
                dev_dbg(dev, "%s - parity = none\n", __func__);
        }

        if (cflag & CSTOPB) {
                lStop = LCR_STOP_2;
                dev_dbg(dev, "%s - stop bits = 2\n", __func__);
        } else {
                lStop = LCR_STOP_1;
                dev_dbg(dev, "%s - stop bits = 1\n", __func__);
        }

        /* figure out the flow control settings */
        rxFlow = txFlow = 0x00;
        if (cflag & CRTSCTS) {
                rxFlow |= IOSP_RX_FLOW_RTS;
                txFlow |= IOSP_TX_FLOW_CTS;
                dev_dbg(dev, "%s - RTS/CTS is enabled\n", __func__);
        } else {
                dev_dbg(dev, "%s - RTS/CTS is disabled\n", __func__);
        }

        /* if we are implementing XON/XOFF, set the start and stop character
           in the device */
        if (I_IXOFF(tty) || I_IXON(tty)) {
                unsigned char stop_char  = STOP_CHAR(tty);
                unsigned char start_char = START_CHAR(tty);

                if (!edge_serial->is_epic ||
                    edge_serial->epic_descriptor.Supports.IOSPSetXChar) {
                        send_iosp_ext_cmd(edge_port,
                                        IOSP_CMD_SET_XON_CHAR, start_char);
                        send_iosp_ext_cmd(edge_port,
                                        IOSP_CMD_SET_XOFF_CHAR, stop_char);
                }

                /* if we are implementing INBOUND XON/XOFF */
                if (I_IXOFF(tty)) {
                        rxFlow |= IOSP_RX_FLOW_XON_XOFF;
                        dev_dbg(dev, "%s - INBOUND XON/XOFF is enabled, XON = %2x, XOFF = %2x\n",
                                __func__, start_char, stop_char);
                } else {
                        dev_dbg(dev, "%s - INBOUND XON/XOFF is disabled\n", __func__);
                }

                /* if we are implementing OUTBOUND XON/XOFF */
                if (I_IXON(tty)) {
                        txFlow |= IOSP_TX_FLOW_XON_XOFF;
                        dev_dbg(dev, "%s - OUTBOUND XON/XOFF is enabled, XON = %2x, XOFF = %2x\n",
                                __func__, start_char, stop_char);
                } else {
                        dev_dbg(dev, "%s - OUTBOUND XON/XOFF is disabled\n", __func__);
                }
        }

        /* Set flow control to the configured value */
        if (!edge_serial->is_epic ||
            edge_serial->epic_descriptor.Supports.IOSPSetRxFlow)
                send_iosp_ext_cmd(edge_port, IOSP_CMD_SET_RX_FLOW, rxFlow);
        if (!edge_serial->is_epic ||
            edge_serial->epic_descriptor.Supports.IOSPSetTxFlow)
                send_iosp_ext_cmd(edge_port, IOSP_CMD_SET_TX_FLOW, txFlow);


        edge_port->shadowLCR &= ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
        edge_port->shadowLCR |= (lData | lParity | lStop);

        edge_port->validDataMask = mask;

        /* Send the updated LCR value to the EdgePort */
        status = send_cmd_write_uart_register(edge_port, LCR,
                                                        edge_port->shadowLCR);
        if (status != 0)
                return;

        /* set up the MCR register and send it to the EdgePort */
        edge_port->shadowMCR = MCR_MASTER_IE;
        if (cflag & CBAUD)
                edge_port->shadowMCR |= (MCR_DTR | MCR_RTS);

        status = send_cmd_write_uart_register(edge_port, MCR,
                                                edge_port->shadowMCR);
        if (status != 0)
                return;

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

        dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
        status = send_cmd_write_baud_rate(edge_port, baud);
        if (status == -1) {
                /* Speed change was not possible - put back the old speed */
                baud = tty_termios_baud_rate(old_termios);
                tty_encode_baud_rate(tty, baud, baud);
        }
}


/****************************************************************************
 * unicode_to_ascii
 *      Turns a string from Unicode into ASCII.
 *      Doesn't do a good job with any characters that are outside the normal
 *      ASCII range, but it's only for debugging...
 *      NOTE: expects the unicode in LE format
 ****************************************************************************/
static void unicode_to_ascii(char *string, int buflen,
                                        __le16 *unicode, int unicode_size)
{
        int i;

        if (buflen <= 0)        /* never happens, but... */
                return;
        --buflen;               /* space for nul */

        for (i = 0; i < unicode_size; i++) {
                if (i >= buflen)
                        break;
                string[i] = (char)(le16_to_cpu(unicode[i]));
        }
        string[i] = 0x00;
}


/****************************************************************************
 * get_manufacturing_desc
 *      reads in the manufacturing descriptor and stores it into the serial
 *      structure.
 ****************************************************************************/
static void get_manufacturing_desc(struct edgeport_serial *edge_serial)
{
        struct device *dev = &edge_serial->serial->dev->dev;
        int response;

        dev_dbg(dev, "getting manufacturer descriptor\n");

        response = rom_read(edge_serial->serial,
                                (EDGE_MANUF_DESC_ADDR & 0xffff0000) >> 16,
                                (__u16)(EDGE_MANUF_DESC_ADDR & 0x0000ffff),
                                EDGE_MANUF_DESC_LEN,
                                (__u8 *)(&edge_serial->manuf_descriptor));

        if (response < 1)
                dev_err(dev, "error in getting manufacturer descriptor\n");
        else {
                char string[30];
                dev_dbg(dev, "**Manufacturer Descriptor\n");
                dev_dbg(dev, "  RomSize:        %dK\n",
                        edge_serial->manuf_descriptor.RomSize);
                dev_dbg(dev, "  RamSize:        %dK\n",
                        edge_serial->manuf_descriptor.RamSize);
                dev_dbg(dev, "  CpuRev:         %d\n",
                        edge_serial->manuf_descriptor.CpuRev);
                dev_dbg(dev, "  BoardRev:       %d\n",
                        edge_serial->manuf_descriptor.BoardRev);
                dev_dbg(dev, "  NumPorts:       %d\n",
                        edge_serial->manuf_descriptor.NumPorts);
                dev_dbg(dev, "  DescDate:       %d/%d/%d\n",
                        edge_serial->manuf_descriptor.DescDate[0],
                        edge_serial->manuf_descriptor.DescDate[1],
                        edge_serial->manuf_descriptor.DescDate[2]+1900);
                unicode_to_ascii(string, sizeof(string),
                        edge_serial->manuf_descriptor.SerialNumber,
                        edge_serial->manuf_descriptor.SerNumLength/2);
                dev_dbg(dev, "  SerialNumber: %s\n", string);
                unicode_to_ascii(string, sizeof(string),
                        edge_serial->manuf_descriptor.AssemblyNumber,
                        edge_serial->manuf_descriptor.AssemblyNumLength/2);
                dev_dbg(dev, "  AssemblyNumber: %s\n", string);
                unicode_to_ascii(string, sizeof(string),
                    edge_serial->manuf_descriptor.OemAssyNumber,
                    edge_serial->manuf_descriptor.OemAssyNumLength/2);
                dev_dbg(dev, "  OemAssyNumber:  %s\n", string);
                dev_dbg(dev, "  UartType:       %d\n",
                        edge_serial->manuf_descriptor.UartType);
                dev_dbg(dev, "  IonPid:         %d\n",
                        edge_serial->manuf_descriptor.IonPid);
                dev_dbg(dev, "  IonConfig:      %d\n",
                        edge_serial->manuf_descriptor.IonConfig);
        }
}


/****************************************************************************
 * get_boot_desc
 *      reads in the bootloader descriptor and stores it into the serial
 *      structure.
 ****************************************************************************/
static void get_boot_desc(struct edgeport_serial *edge_serial)
{
        struct device *dev = &edge_serial->serial->dev->dev;
        int response;

        dev_dbg(dev, "getting boot descriptor\n");

        response = rom_read(edge_serial->serial,
                                (EDGE_BOOT_DESC_ADDR & 0xffff0000) >> 16,
                                (__u16)(EDGE_BOOT_DESC_ADDR & 0x0000ffff),
                                EDGE_BOOT_DESC_LEN,
                                (__u8 *)(&edge_serial->boot_descriptor));

        if (response < 1)
                dev_err(dev, "error in getting boot descriptor\n");
        else {
                dev_dbg(dev, "**Boot Descriptor:\n");
                dev_dbg(dev, "  BootCodeLength: %d\n",
                        le16_to_cpu(edge_serial->boot_descriptor.BootCodeLength));
                dev_dbg(dev, "  MajorVersion:   %d\n",
                        edge_serial->boot_descriptor.MajorVersion);
                dev_dbg(dev, "  MinorVersion:   %d\n",
                        edge_serial->boot_descriptor.MinorVersion);
                dev_dbg(dev, "  BuildNumber:    %d\n",
                        le16_to_cpu(edge_serial->boot_descriptor.BuildNumber));
                dev_dbg(dev, "  Capabilities:   0x%x\n",
                      le16_to_cpu(edge_serial->boot_descriptor.Capabilities));
                dev_dbg(dev, "  UConfig0:       %d\n",
                        edge_serial->boot_descriptor.UConfig0);
                dev_dbg(dev, "  UConfig1:       %d\n",
                        edge_serial->boot_descriptor.UConfig1);
        }
}


/****************************************************************************
 * load_application_firmware
 *      This is called to load the application firmware to the device
 ****************************************************************************/
static void load_application_firmware(struct edgeport_serial *edge_serial)
{
        struct device *dev = &edge_serial->serial->dev->dev;
        const struct ihex_binrec *rec;
        const struct firmware *fw;
        const char *fw_name;
        const char *fw_info;
        int response;
        __u32 Operaddr;
        __u16 build;

        switch (edge_serial->product_info.iDownloadFile) {
                case EDGE_DOWNLOAD_FILE_I930:
                        fw_info = "downloading firmware version (930)";
                        fw_name = "edgeport/down.fw";
                        break;

                case EDGE_DOWNLOAD_FILE_80251:
                        fw_info = "downloading firmware version (80251)";
                        fw_name = "edgeport/down2.fw";
                        break;

                case EDGE_DOWNLOAD_FILE_NONE:
                        dev_dbg(dev, "No download file specified, skipping download\n");
                        return;

                default:
                        return;
        }

        response = request_ihex_firmware(&fw, fw_name,
                                    &edge_serial->serial->dev->dev);
        if (response) {
                dev_err(dev, "Failed to load image \"%s\" err %d\n",
                       fw_name, response);
                return;
        }

        rec = (const struct ihex_binrec *)fw->data;
        build = (rec->data[2] << 8) | rec->data[3];

        dev_dbg(dev, "%s %d.%d.%d\n", fw_info, rec->data[0], rec->data[1], build);

        edge_serial->product_info.FirmwareMajorVersion = rec->data[0];
        edge_serial->product_info.FirmwareMinorVersion = rec->data[1];
        edge_serial->product_info.FirmwareBuildNumber = cpu_to_le16(build);

        for (rec = ihex_next_binrec(rec); rec;
             rec = ihex_next_binrec(rec)) {
                Operaddr = be32_to_cpu(rec->addr);
                response = sram_write(edge_serial->serial,
                                     Operaddr >> 16,
                                     Operaddr & 0xFFFF,
                                     be16_to_cpu(rec->len),
                                     &rec->data[0]);
                if (response < 0) {
                        dev_err(&edge_serial->serial->dev->dev,
                                "sram_write failed (%x, %x, %d)\n",
                                Operaddr >> 16, Operaddr & 0xFFFF,
                                be16_to_cpu(rec->len));
                        break;
                }
        }

        dev_dbg(dev, "sending exec_dl_code\n");
        response = usb_control_msg (edge_serial->serial->dev,
                                    usb_sndctrlpipe(edge_serial->serial->dev, 0),
                                    USB_REQUEST_ION_EXEC_DL_CODE,
                                    0x40, 0x4000, 0x0001, NULL, 0, 3000);

        release_firmware(fw);
}


/****************************************************************************
 * edge_startup
 ****************************************************************************/
static int edge_startup(struct usb_serial *serial)
{
        struct edgeport_serial *edge_serial;
        struct usb_device *dev;
        struct device *ddev = &serial->dev->dev;
        int i;
        int response;
        bool interrupt_in_found;
        bool bulk_in_found;
        bool bulk_out_found;
        static __u32 descriptor[3] = {  EDGE_COMPATIBILITY_MASK0,
                                        EDGE_COMPATIBILITY_MASK1,
                                        EDGE_COMPATIBILITY_MASK2 };

        dev = serial->dev;

        /* create our private serial structure */
        edge_serial = kzalloc(sizeof(struct edgeport_serial), GFP_KERNEL);
        if (!edge_serial)
                return -ENOMEM;

        spin_lock_init(&edge_serial->es_lock);
        edge_serial->serial = serial;
        usb_set_serial_data(serial, edge_serial);

        /* get the name for the device from the device */
        i = usb_string(dev, dev->descriptor.iManufacturer,
            &edge_serial->name[0], MAX_NAME_LEN+1);
        if (i < 0)
                i = 0;
        edge_serial->name[i++] = ' ';
        usb_string(dev, dev->descriptor.iProduct,
            &edge_serial->name[i], MAX_NAME_LEN+2 - i);

        dev_info(&serial->dev->dev, "%s detected\n", edge_serial->name);

        /* Read the epic descriptor */
        if (get_epic_descriptor(edge_serial) <= 0) {
                /* memcpy descriptor to Supports structures */
                memcpy(&edge_serial->epic_descriptor.Supports, descriptor,
                       sizeof(struct edge_compatibility_bits));

                /* get the manufacturing descriptor for this device */
                get_manufacturing_desc(edge_serial);

                /* get the boot descriptor */
                get_boot_desc(edge_serial);

                get_product_info(edge_serial);
        }

        /* set the number of ports from the manufacturing description */
        /* serial->num_ports = serial->product_info.NumPorts; */
        if ((!edge_serial->is_epic) &&
            (edge_serial->product_info.NumPorts != serial->num_ports)) {
                dev_warn(ddev,
                        "Device Reported %d serial ports vs. core thinking we have %d ports, email greg@kroah.com this information.\n",
                         edge_serial->product_info.NumPorts,
                         serial->num_ports);
        }

        dev_dbg(ddev, "%s - time 1 %ld\n", __func__, jiffies);

        /* If not an EPiC device */
        if (!edge_serial->is_epic) {
                /* now load the application firmware into this device */
                load_application_firmware(edge_serial);

                dev_dbg(ddev, "%s - time 2 %ld\n", __func__, jiffies);

                /* Check current Edgeport EEPROM and update if necessary */
                update_edgeport_E2PROM(edge_serial);

                dev_dbg(ddev, "%s - time 3 %ld\n", __func__, jiffies);

                /* set the configuration to use #1 */
/*              dev_dbg(ddev, "set_configuration 1\n"); */
/*              usb_set_configuration (dev, 1); */
        }
        dev_dbg(ddev, "  FirmwareMajorVersion  %d.%d.%d\n",
            edge_serial->product_info.FirmwareMajorVersion,
            edge_serial->product_info.FirmwareMinorVersion,
            le16_to_cpu(edge_serial->product_info.FirmwareBuildNumber));

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

        response = 0;

        if (edge_serial->is_epic) {
                /* EPIC thing, set up our interrupt polling now and our read
                 * urb, so that the device knows it really is connected. */
                interrupt_in_found = bulk_in_found = bulk_out_found = false;
                for (i = 0; i < serial->interface->altsetting[0]
                                                .desc.bNumEndpoints; ++i) {
                        struct usb_endpoint_descriptor *endpoint;
                        int buffer_size;

                        endpoint = &serial->interface->altsetting[0].
                                                        endpoint[i].desc;
                        buffer_size = usb_endpoint_maxp(endpoint);
                        if (!interrupt_in_found &&
                            (usb_endpoint_is_int_in(endpoint))) {
                                /* we found a interrupt in endpoint */
                                dev_dbg(ddev, "found interrupt in\n");

                                /* not set up yet, so do it now */
                                edge_serial->interrupt_read_urb =
                                                usb_alloc_urb(0, GFP_KERNEL);
                                if (!edge_serial->interrupt_read_urb) {
                                        response = -ENOMEM;
                                        break;
                                }

                                edge_serial->interrupt_in_buffer =
                                        kmalloc(buffer_size, GFP_KERNEL);
                                if (!edge_serial->interrupt_in_buffer) {
                                        response = -ENOMEM;
                                        break;
                                }
                                edge_serial->interrupt_in_endpoint =
                                                endpoint->bEndpointAddress;

                                /* set up our interrupt urb */
                                usb_fill_int_urb(
                                        edge_serial->interrupt_read_urb,
                                        dev,
                                        usb_rcvintpipe(dev,
                                                endpoint->bEndpointAddress),
                                        edge_serial->interrupt_in_buffer,
                                        buffer_size,
                                        edge_interrupt_callback,
                                        edge_serial,
                                        endpoint->bInterval);

                                interrupt_in_found = true;
                        }

                        if (!bulk_in_found &&
                                (usb_endpoint_is_bulk_in(endpoint))) {
                                /* we found a bulk in endpoint */
                                dev_dbg(ddev, "found bulk in\n");

                                /* not set up yet, so do it now */
                                edge_serial->read_urb =
                                                usb_alloc_urb(0, GFP_KERNEL);
                                if (!edge_serial->read_urb) {
                                        response = -ENOMEM;
                                        break;
                                }

                                edge_serial->bulk_in_buffer =
                                        kmalloc(buffer_size, GFP_KERNEL);
                                if (!edge_serial->bulk_in_buffer) {
                                        response = -ENOMEM;
                                        break;
                                }
                                edge_serial->bulk_in_endpoint =
                                                endpoint->bEndpointAddress;

                                /* set up our bulk in urb */
                                usb_fill_bulk_urb(edge_serial->read_urb, dev,
                                        usb_rcvbulkpipe(dev,
                                                endpoint->bEndpointAddress),
                                        edge_serial->bulk_in_buffer,
                                        usb_endpoint_maxp(endpoint),
                                        edge_bulk_in_callback,
                                        edge_serial);
                                bulk_in_found = true;
                        }

                        if (!bulk_out_found &&
                            (usb_endpoint_is_bulk_out(endpoint))) {
                                /* we found a bulk out endpoint */
                                dev_dbg(ddev, "found bulk out\n");
                                edge_serial->bulk_out_endpoint =
                                                endpoint->bEndpointAddress;
                                bulk_out_found = true;
                        }
                }

                if (response || !interrupt_in_found || !bulk_in_found ||
                                                        !bulk_out_found) {
                        if (!response) {
                                dev_err(ddev, "expected endpoints not found\n");
                                response = -ENODEV;
                        }

                        usb_free_urb(edge_serial->interrupt_read_urb);
                        kfree(edge_serial->interrupt_in_buffer);

                        usb_free_urb(edge_serial->read_urb);
                        kfree(edge_serial->bulk_in_buffer);

                        kfree(edge_serial);

                        return response;
                }

                /* start interrupt read for this edgeport this interrupt will
                 * continue as long as the edgeport is connected */
                response = usb_submit_urb(edge_serial->interrupt_read_urb,
                                                                GFP_KERNEL);
                if (response)
                        dev_err(ddev, "%s - Error %d submitting control urb\n",
                                __func__, response);
        }
        return response;
}


/****************************************************************************
 * edge_disconnect
 *      This function is called whenever the device is removed from the usb bus.
 ****************************************************************************/
static void edge_disconnect(struct usb_serial *serial)
{
        struct edgeport_serial *edge_serial = usb_get_serial_data(serial);

        if (edge_serial->is_epic) {
                usb_kill_urb(edge_serial->interrupt_read_urb);
                usb_kill_urb(edge_serial->read_urb);
        }
}


/****************************************************************************
 * edge_release
 *      This function is called when the device structure is deallocated.
 ****************************************************************************/
static void edge_release(struct usb_serial *serial)
{
        struct edgeport_serial *edge_serial = usb_get_serial_data(serial);

        if (edge_serial->is_epic) {
                usb_kill_urb(edge_serial->interrupt_read_urb);
                usb_free_urb(edge_serial->interrupt_read_urb);
                kfree(edge_serial->interrupt_in_buffer);

                usb_kill_urb(edge_serial->read_urb);
                usb_free_urb(edge_serial->read_urb);
                kfree(edge_serial->bulk_in_buffer);
        }

        kfree(edge_serial);
}

static int edge_port_probe(struct usb_serial_port *port)
{
        struct edgeport_port *edge_port;

        edge_port = kzalloc(sizeof(*edge_port), GFP_KERNEL);
        if (!edge_port)
                return -ENOMEM;

        spin_lock_init(&edge_port->ep_lock);
        edge_port->port = port;